September 15-19

CIRSE 2012Lisbon, Portugal

ABSTRACTS &AUTHOR INDEX

PART 1: Special Sessions, Foundation Courses, Honorary Lectures,Hot Topic Lectures,CIRSE Meets Lectures

PART 2: Free PapersPART 3: Electronic PostersPART 4: Author Index

Online Publication Number:10.1007/s00270-012-437-6

C RSECardiovascular and Interventional Radiological Society of Europe

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Abstracts ofSpecial SessionsFoundation CoursesHonorary LecturesHot Topic LecturesCIRSE Meets Lecturessorted by presentationnumbers

C RSECardiovascular and Interventional Radiological Society of Europe

September 15-19

CIRSE 2012Lisbon, Portugal

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Foundation CourseArterial puncture: how I do it

101.1Easy and difficult antegrade femoral artery punctureH.-J. Wagner;Department of Radiology, Vivantes Klinikum im Friedrichshain, Berlin, Germany.

Learning Objectives1. To learn about the technique of antegrade femoral artery

puncture2. To learn which tricks may help to perform the puncture success-

fully3. To learn how ultrasound may help to perform the antegrade

puncture

No abstract available.

101.2How to perform transpopliteal arterial punctureA.-M. Belli;Department of Radiology, St Georges Hospital, London, United Kingdom.

Learning Objectives1. To learn when a transpopliteal approach may be considered2. To learn about the important structures surrounding the popliteal

artery3. To learn which technique should be applied and which material

should be usedA transpopliteal approach for angioplasty may be considered in the following:1. A hostile groin due to scarring following previous surgery, recent surgical intervention with fresh scars, infection or obesity.2. When an antegrade approach fails.3. When the common femoral artery is occluded.4. When there is an SFA occlusion flush with the origin.The popliteal artery must be patent with no significant stenosis at the site of puncture. It is easiest if the patient is able to lie prone, but a transpopliteal puncture can still be performed with the patient supine and the leg supported with the knee inverted. Most transpopliteal arterial punctures are retrogradele, but an antegrade puncture may also be performed. Puncture is best guided by ultra-sound (US) to identify and avoid the popliteal vein. Avoid excessive pressure with the US probe as this compresses the vein and may prevent recognition of it. The popliteal vein lies directly behind the artery at the level of the knee joint but then moves lateral to the artery as it progresses up the thigh. It is advisable to avoid punc-turing the vein en route as an arterio venous fistula may develop which could worsen ischaemia. The site of puncture is usually above the level of the knee joint, but it is possible to puncture the popli-teal artery anywhere along its length to allow a reasonably stable position before the wire enters the occlusion. Although it is eas-ier to puncture fairly healthy, wide arteries, it is possible to punc-ture diseased, underperfused, small popliteal arteries with careful technique. In normal diameter arteries a 6 Fr sheath can be safely inserted, but the use of 4 Fr sheaths with compatible catheters and stents is advantageous in small arteries, and is being increasingly used. Once access has been obtained, a bolus of heparin and anti-spasmodics are usually given to help prevent spasm and occlusion of the artery. Doppler-equipped needles have been successfully used in the past, but do not always identify the best path to avoid the vein and have no advantage over simple US guidance. Direct

visualisation with contrast injected from above is another simple method if there is arterial access from another site, but this also has the disadvantage of inadvertent venous puncture. The complica-tion rate of popliteal puncture is approximately 5%. The main com-plications are reported as haematoma and arterio-venous fistu-lae although occlusion is also a risk, particularly in heavily diseased arteries.References1. Heenan SD, Vinnicombe SJ, Buckenham TM, Belli AM

Percutaneous transluminal angioplasty by a retrograde subinti-mal approach Clinical Radiology 1994, 49:824-7.

2. Brountzos EN, Moulakakis KG, Avqerinos ED, Dalainas I, et al Retrograde transpopliteal approach of iliofemoral lesions Vasc and Endovascular Surgery 2011,45: 646-50.

3. Kluge A, Rauber K, Breithecker A, Rau WS, Bachmann G Puncture of the popliteal artery using a Doppler-equipped (SMART) nee-dle in transpopliteal interventions European Radiology 2003, 13:1972-8.

4. Evans C, Peter N, Gibson M, Torrie EP, Galland RB, Magee TR Five year retrograde transpopliteal angioplasty results com-pared with antegrade angioplasty Ann R Coll Surg Engl, 2010,92:347-52.

101.3How to perform brachial arterial punctureM. Di Primio;Interventional Radiology, Hpital Europen Georges Pompidou, Paris, France.

Learning Objectives1. To learn when a transbrachial approach may be considered2. To learn about the specific risks of the transbrachial approach3. To learn which technique should be applied and which materials

should be used

No abstract available.

101.4How to treat access site complicationsD.K. Tsetis;Interventional Radiology Unit, Department of Radiology, University Hospital Iraklion, Iraklion, Greece.

Learning Objectives1. To learn about the typical access site complications2. To learn about the technique for the treatment of pseudoaneu-

rysms3. To learn the different possibilities to manage access site complica-

tions including surgeryThe type of local vascular complications at the arterial entry site var-ies with respect to the puncture site and the method applied for catheterization. With transfemoral approach, complications occur in the form of hematoma or uncontrollable bleeding, pseudoaneu-rysm, arterial dissection or acute thrombosis, and A-V fistula. When catheterization is performed via the arteries of the arm, hematoma, vascular occlusion and pseudoaneurysm must be expected. Each of these complications may have the potential for serious morbid-ity. Surgical repair of iatrogenic arterial access lesions is associated with considerable postoperative morbidity and mortality rates due to the significant comorbidities of the treated patients. These open surgical procedures, although very often performed under general anesthesia, are potentially hazardous, since they increase the stress load in these patients, many of whom are in an unstable condition; in addition, the existing hematoma and local tissue injury frequently found in such iatrogenically traumatized areas predispose to poor

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wound healing and postoperative infection, especially if interposi-tion of a synthetic graft is needed. On the other hand endovascu-lar repair can be performed under local anesthesia, is well tolerated by the patient, and is associated with a shorter hospitalization time than that of surgery. Stent-grafts are safe, effective, and durable devices for the treatment of uncontrollable bleeding. A stent-graft with a diameter 1-2 mm larger than the vessel diameter, to ensure correct anchorage, is typically selected. Stent-graft implantation is also an attractive endovascular treatment option for iatrogenic A-V fistulas, and for pseudoaneurysms not amenable to treatment with percutaneous thrombin injection. Self-expanding stent-grafts, espe-cially the new generation with nitinol endoskeleton, should be pre-ferred in the area of the groin, because they show increased resis-tance to external compression and bending stress. Percutaneous thrombin injection is nowadays the treatment of choice for non-complicated arterial pseudoaneurysms with a distinct neck. Anticoagulation does not seem to affect the efficacy of the proce-dure. Where the neck of the PA is absent or is short and wide, percu-taneous thrombin injection should be performed with simultaneous balloon occlusion across the entry site of the PA. In acute iliofemoral thrombotic occlusions catheter-directed thrombolysis is a reliable treatment option, although there are no large series in the literature supporting its widespread use. Following successful lysis, percuta-neous transluminal angioplasty with prolonged balloon inflation is indicated for underlying localized CFA dissections, while a self-expandable stent should be deployed in order to treat more exten-sive dissections involving the external iliac artery.References1. Muller DWM, Shamir KJ, Ellis SG, Topol EJ. Peripheral vascular

complications after conventional and complex percutaneous coronary intervention procedures. Am J Cardiol 1992; 69:6368.

2. Tsetis D. Endovascular Treatment of Complications of Femoral Arterial Access. Cardiovasc Intervent Radiol. 2010 ;33: 457-68.

3. Franco CD, Goldsmith J, Veith F, Calligaro KD, Gupta SK, Wengerter KR. Management of arterial injuries produced by per-cutaneous femoral procedures. Surgery 1993; 113:419425

4. McCann RL, Schwartz LB, Pieper KS. Vascular complications of cardiac catheterization. J Vasc Surg 1991; 14:375381.

5. Onal B, Kosar S, Gumus T, Ilgit ET, Akpek S. Postcatheterization femoral arteriovenous fistulas: endovascular treatment with stentgrafts. Cardiovasc Interv Radiol 2004; 27:453 458

6. Morgan R, Belli AM. Current treatment methods for postcatheter-ization pseudoaneurysms. J Vasc Interv Radiol 2003; 14: 697710.

7. Tsetis DK, Kochiadakis GE, Hatzidakis AA et al. Transcatheter thrombolysis with high-dose bolus tissue plasminogen activator in iatrogenic arterial occlusion after femoral arterial catheteriza-tion. Cardiovasc Interv Radiol 2002; 25:3641.

8. Oweida SW, Roubin GS, Smith RB, Salam AA. Postcatheterization vascular complications associated with percutaneous translumi-nal coronary angioplasty. J Vasc Surg 1990; 12:310315.

Special SessionHow to manage renal transplant complications

102.1Renal transplant nephrostomy: how I do itP. Pappas;Radiology, Laiko Gen. Hosp. Athens, Athens, Greece.

Learning Objectives1. To review indications for transplant nephrostomy 2. To review technique and results for transplant nephrostomy3. To review complications of transplant nephrostomy and how to

deal with them Concerning renal transplantation, advances in the management of graft rejection have led to improved graft and patient survival rates; however, other types of complications have now become more apparent, e.g. vascular or urological. The most common uro-logical complications following renal transplantation are ureteral obstruction and leak, constituting a significant problem on renal grafts survival. The most important aspects of these complications are early diagnosis and prompt treatment since any retard in their management may lead to renal graft dysfunction or even graft loss. Development in interventional radiology has provided minimally invasive means to treat urological complications with low complica-tion rates. Urological complications including urinary leaks and ure-teric obstruction represent the most important subgroup of nonvas-cular problems. As recorded in most recent studies their incidence ranges from 3% to 8% [1,2]. The traditional method of treatment of these complications has been surgical revision, which entails an increased risk of graft loss. With the development of percutaneous modes of treatment, interventional radiology offers a viable alter-native to surgery, with lower complication rates. Ureteric obstruc-tions that are generally classified as early (3 months) depending on when they occur in relation to the time of transplantation have vari-ous causes. Nevertheless, as many studies highlight the significant difference between them in practice is that early stenosis tends to be a result of mechanical causes, such as kinks, edema, blood clots or restrictive submucosal tunnel, whereas late stenosis is provoked by generalized or focal fibrosis resulting from ischemia or rejection [3,4]. Consequently, the majority of early obstructions are likely to resolve with percutaneous management while late obstructions are prone to recurrency due to fibrotic surrounding environment that cannot be eliminated with any procedure. The most common location of obstruction is at the distal ureter and the uretero-vesical junction and it seems that ischemia resulting from problems in oper-ative technique during harvesting or from high dose of immunosup-pression is a major etiological factor for these segmental stenoses [3,5,6,7] . Clinical, laboratory and imaging manifestations of obstruc-tive uropathy, commonly used for proper diagnosis are tenderness or discomfort over the kidney, decrease in urine output, elevated serum urea and creatinine values, hydronephrosis on renal scan, pel-vicalyceal dilation on ultrasound examination and relatively normal blood flow on color Doppler ultrasound. There should be high suspi-cion of this complication in order to be differentiated from rejection, since delay in accurate diagnosis and inappropriate antirejection therapy may result in loss of transplanted kidney as well as increased patient morbidity and mortality. Percutaneous management of ure-teral stenosis consists of percutaneous nephrostomy, balloon dila-tion, insertion of the double J stent and rarely metallic stent place-ment. Percutaneous nephrostomy is a well-established therapy for urinary drainage in patients with supra-vesical urinary tract obstruc-tion, and for urinary diversion, as in patients with urinary fistulae, leaks, or hemorrhagic cystitis as well as for stone removal and other endoscopic procedures. The other major urologic complication of renal transplantation, id urine leakage, is also prone to percutaneous

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treatment through nephrostomy and antegrade ureteral endopros-thesis placement, with almost the same technique with that we describe thereafter. In particular, although there is technical diver-sification among interventional radiologists according to each ones experience, a commonly adopted procedure includes puncture of a dilated calyx by a 22g needle under U/S guidance, as it is usually sug-gested in any type of nephrostomy. Ultrasound examination is done before in any case, in order to exclude a possible collection in the vicinity, the interference of gut between the graft and the anterior abdominal wall, etc. The calyx to be punctured must be closer to the anterior abdominal wall, without anything like gut or liquid collec-tion interfering between the abdominal wall and the graft, and must also have a straight continuity with the renal pelvis and the ureter, in order to avoid kinking of the guide wires that may lead to com-plications or failure of the procedure. When the needle tip is within the collecting system, urine is aspirated and contrast medium is injected. If there is no dilation of the collecting system of the trans-planted kidney, as in cases with urine leaks, there could be a mod-ification of the method, either to search for a non-dilated calyx with the ultrasound beam, try to get in and, instead of urine aspi-ration, proceed directly with small diluted contrast medium injec-tions, to verify position in collecting system, or otherwise to delin-eate the collecting system after intravenous injection of the contrast medium, and try to puncture the calyx with the Ciba needle under fluoroscopic guidance. After verification of correct placement of the Ciba needle into the collecting system, a short 0.18-in guide wire is inserted through the Ciba needle and the calyx up to the renal pel-vis or the upper third of the ureter, over which a three-part system sheath is advanced into the renal pelvis. Anatomical information and an assessment of the rate of flow of contrast down the ureter into the bladder are provided from antegrade pyelograms. Afterwards, when there are no signs of hematuria, pain or infection, selective catheterization of stenotic area usually follows. Tract dilation fol-lows and a percutaneous nephrostomy tube is placed at the end. After careful and thorough investigation of the literature, we have assumed that technical success rate of percutaneous management is significantly high (from 58% up to 95%) [7,8,9] resulting in amelio-ration of renal graft function. With regard to procedure-related com-plications, most studies mention minor complications without per-manent damage to the transplanted kidney. The overall complica-tion rate reported by Bhagat et al. [4] was 27% (12 of 45 patients): 7 patients developed infections which resolved with antibiotics, 2 patients experienced urinary leakage at nephrostomy treated ade-quately by replacing the nephrostomy catheter with another of larger diameter, whereas 3 others necessitated antegrade percuta-neous replacement of the catheter. Thus, percutaneous manage-ment of ureteral stenosis ameliorates graft function with a low com-plication rate and low risk of the grafts survival. During the past nine years in our department 47 nephrostomies were performed in 45 patients with renal transplantation. The puncture of the saf-est calyx was performed using the Seldinger technique as described above. In 44 patients a ureteral endoprothesis was placed through the nephrostomy pathway. A nephrostomy tube placement was possible in all cases (technical success 100%). In 41 patients renal function was ameliorated (91.1%). 1 patient (0.02%) presented mas-sive hemorrhage which was successfully treated with percutaneous intra-arterial superselective catheterization and embolization of the punctured branch of the renal artery. No deaths were assessed to the method (procedure-related mortality was 0%). In conclusion, we suggest that the percutaneous approach is the first-line treatment of choice for ureteral obstruction following kidney transplantation as it shows a low risk for the grafts survival, ameliorates renal func-tion and shows low immediate and long-term complication rates. Surgery should be reserved only for patients who fail to benefit from interventional treatment for its higher rate of graft dysfunction, loss and recurrence.

References1. Steeter EH, Little DM, Cranston DW et al: The urological compli-

cations of renal transplantation: a series of 1535 patients. BJU Int 90:627, 2002.

2. Kaskarelis I, Koukoulaki M, Georgantas T, et al: Ureteral compli-cations in renal transplant recipients successfully treated with interventional radiology. Transplantation Proceedings 40:3170, 2008.

3. Bgahta VJ, Gordon RL, Osorio RW, et al: Ureteral obstructions and leaks after transplantation. Outcome of percutaneous antegrade ureteral stent placement in 44 patients: Radiology 148:407, 2009.

4. Collado A, Caparros J, Guirado L, et al: Balloon dilation in the treatment of ureteral stenosis in kidney transplant recipients. Eur Urol 34:399,1998.

5. Kim JC, Banner MP, Ramchadani P, et al: Balloon dilation of ure-teral strictures after renal transplantation. Radiology 186:717, 1993.

6. Subodh R, Jaydeep D, Tushar A, et al: Unusual causes of obstruc-tion to transplant ureter. Saudi J Kidney Transplant 21:310, 2010.

7. Yong AA, Ball ST, Pelling MX et al: Management of urteral stric-tures in renal transplants by antegrade balloon dilatation and temporary internal stenting. Cardiovasc Intervent Radiol 22:385, 1998.

8. Peregrin J, Filipova H, Matl I et al: Percutaneous treatment of early and late ureteral stenosis after renal transplantation. Transplant Proc 29:140, 1997.

9. Henry C, Irving, Habib Kashi S, et al: Complications of renal transplantation and the role of interventional radiology. J Clin Ultrasound 20:545, 1992.

102.2Ureteric strictures: how to treat themP.J. Haslam;Interventional Radiology, Freeman Hospital, Newcastle-upon-Tyne, United Kingdom.

Learning Objectives1. To review assessment and imaging work-up of ureteric strictures2. To review technique and results of IR for ureteric strictures3. To review complications of IR for ureteric strictures and how to

deal with them Renal transplantation can make a huge difference to the quality of life for patients with chronic renal failure. There are many reasons for a renal transplant to fail or function poorly and there are numerous post-operative complications. Ureteric problems are the most common and often arise from the vesicoureteric anastomosis. These are most fre-quently due to ischaemia or technical problems at the time of surgery.Complications at the anastomosis occur in reported incidences of 0 to 33% and present with renal functional impairment due to obstruction, or urine leaks presenting as increased drain output or intra-abdominal collections. Some centres routinely stent transplant ureters in an attempt to reduce the incidence of these complica-tions. When complications occur it is important that they are man-aged appropriately and using techniques to minimise the need for future intervention and surgery.Initial management of most ureteric strictures is by transplant neph-rostomy. These are usually straightforward as the transplant is eas-ily accessible and doesnt move. If the patient is septic I do not per-form a nephrostogram due to the risk of sepsis and defer until the kidney has been decompressed for a few days. The ureter can then be assessed with a good quality antegrade study prior to any fur-ther intervention. Alternative imaging can be performed with CT or MRI, which can be useful to assess any extrinsic causes of ure-teric obstruction. On occasion, cone beam CT performed with an antegrade study can provide useful insight into the aetiology of obstruction.

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Intervention for ureteric strictures is primarily based around ante-grade stent insertion with repeated stent changes as a long term option for some patients. Ureteroplasty with high pressure balloons is often needed. Alternative types of stent such as metallic or bio-compatible stents can be used and these will also be discussed.

102.3Transplant renal artery stenosis: techniques - PTA vs. stentJ.H. Peregrin;Diagnostic and Interventional Radiology, Inst. for Clinical and Experimental Medicine, Prague, Czech Republic.

Learning Objectives1. To review indications for IR for transplant renal artery stenosis2. To review technique and results for IR for transplant renal artery

stenosis3. To review indications for PTA versus stenting in transplant renal

artery stenosisThe incidence of transplanted kidney artery stenosis (TRAS) is reported in the range of 1-23% (1, 2, 3, 4, 5), the number of posi-tive diagnoses increased with introduction of duplex sonography, CT angiography (6) and MR angiography (7) as even asymptomatic patients are diagnosed (8). Wide range of reported TRAS incidence is most likely influenced by nonstandard definition of hemodynamic significance of TRAS (9, 10). Reported causes of TRAS are as follows: surgical failure, graft type (higher TRAS incidence is reported in pediatric cadaverous kidney donors (11, 12), although not all authors confirm this situation (13)), immunological causes (9, 14), CMV infec-tion (15, 16), progression of the recipient atheromatous disease prox-imally to the graft anastomosis (17). It was repeatedly documented that patients with TRAS have not only worse graft survival, but as well overall survival rate (14, 18). Angioplasty (PTA) is for many years considered as a method of choice in TRAS treatment (9, 19, 20). In the majority of cases TRAS responds well to balloon dilatation (in recent years more frequently combined with stent implantation). Diagnosis of TRAS is usually based on Doppler ultrasound examination and MR angiography, rarely on CT angiography (contrast medium load). Digital subtraction angiography remains diagnostic gold standard, but it should be performed only in case when in case of positive result - immediate endovascular intervention is planned. The tech-nique of the procedure depends on the technique of the transplan-tation. In the graft arterial anastomosis of end to side type to the external iliac artery, the approach from ipsilateral femoral artery is usually used, except for the cases where graft artery has very acute caudal angulation where contralateral approach is necessary. In cases of end to end anastomosis to internal iliac artery a contralat-eral (crossover) approach is most frequently used. A simple bal-loon dilatation is usually employed as a primary measure followed by stent placement in the case of suboptimal outcome or complica-tion (occlusive dissection). Some authors use primary stenting, but there are no randomized data confirming the superiority of primary stenting over plain balloon angioplasty with selective stent place-ment (21, 22). There are no reports on drug-eluting stents use or protection devices use during TRAS angioplasty. Medication before and after angioplasty does not differ from native kidneys PTA (anti-aggregation using combination of Plavix and ASA before and after the procedure, Heparin 3000-5000 units during angioplasty). The amount of contrast medium used should be as low as possible and the patient should be well hydrated to avoid contrast-induced nephropathy (in patients with impaired graft function especially). Technical success rate of TRAS angioplasty is reported as 70-90%, with low complication rate and the restenosis rate of 10-12% (22, 23, 24, 25, 26, 27, 28,). Clinical results of TRAS angioplasty are reported in several papers. The majority of them are dedicated to hyperten-sion treatment and the authors generally agree on the fact that in some of the patients blood pressure decreases after successful PTA,

but almost in none of the cases blood pressure is normal without the medication. However, the results are difficult to compare due to non-standard methods of evaluation (20, 29). Nevertheless, it is nec-essary to remind that hypertension in patients with kidney trans-plant increases the risk of cardiovascular disease and plays a role in chronic graft dysfunction progression (30). Despite the fact that hypertension remains the most frequent indication to graft artery PTA, it is repeatedly confirmed that successful angioplasty can favor-ably influence failing graft function (9, 14, 15, 16, 18). Besides that it was shown that patients with untreated TRAS have poorer graft sur-vival associated with poorer patients survival as well (14). In some papers it is reported that successful TRAS PTA can restore the kid-ney function even in the dialyzed patients with complete graft fail-ure (18). Complications of graft artery PTRA are most often classi-cal catheterization complications (groin hematoma, bleeding, false aneurysm). Graft function impairment caused by angioplasty is not frequent and rather caused by contrast-induced nephropathy than graft artery damage or distal embolization (20, 24, 28); occlusive dis-sections reported in the past are now solved by stent placement.References1. Chandrasoma P, Aberle AM. Anastomotic line renal artery steno-

sis after transplantation.J Urol 1986;135(6): 1159-1162.2. Lacombe M. Renal artery stenosis after renal transplantation.

Ann Vasc Surg 1988; 2(2): 155-160.3. Morris PJ, Yadav RV, Kincaid-Smith P, et al. Renal artery stenosis in

renal transplantation. Med J Aust 1971; 1: 1255-1257.4. Munda R, Alexander JW, Miller S, First MR, Fidler JP. Renal

allograft artery stenosis. Am J Surg 1977; 134(3): 400-403.5. Roberts JP, Ascher NL, Fryd DS, et al. Transplant renal artery ste-

nosis. Transplantation 1989; 48(4):580-583.6. Mell MW, Alfrey EJ, Rubin GD, Scandling JD, Jeffrey RB, Dafoe DC.

Use of spiral computed tomography in the diagnosis of trans-plant renal artery stenosis. Transplantation 1994; 57: 746-748.

7. Luk SH, Chan JH, Kwan TH, Tsui WC, Cheung YK, Yuen MK. Breath-hold 3D gadolinium-enhanced subtraction MRA in the detection of transplant renal artery stenosis. Clin Radiol 1999; 54: 651-654.

8. Bruno S, Remuzzi G, Ruggenenti P. Transplant renal artery steno-sis. J Am Soc Nephrol 2004; 15(1): 134-141.

9. Audard V, Matignon M, Hemery F, et al. Risk factors and long-term outcome of transplant renal artery stenosis in adult recipi-ents after treatment by percutaneous transluminal angioplasty. Am J Transplant 2006; 6(1): 95-99.

10. Fervenza FC, Lafayette RA, Alfrey EJ, Petersen J. Renal artery stenosis in kidney transplantation. Am J Kidney Dis 1998; 31: 142-148.

11. Marques M, Prats D, Snchez-Fructuoso A, et al. A. Incidence of renal artery stenosis in pediatric en bloc and adult single kidney transplants. Transplantation 2001; 71(1): 164-166.

12. Stanley P, Malekzadeh M, Diament MJ. Posttransplant renal artery stenosis: angiographic study in 32 children. Am J Roentgenol 1987; 148(3): 487-490.

13. Fauchald P, Vatne K, Paulsen D, et al: Long-term clinical results of percutaneous transluminal angioplasty in transplant renal artery stenosis. Nephrol Dial Transplant 1992; 7: 256-259.

14. Wong W, Fynn SP, Higgins RM, et al. Transplant renal artery ste-nosis in 77 patients-does it have an immunological cause? Transplantation 1996; 61(2): 215-219.

15. Pouria S, State OI, Wong W, Hendry BM. CMV infection is associ-ated with transplant renal artery stenosis. QJM 1998; 91: 185-189.

16. Humar A, Uknis M, Papalois V, Gillingham K, Matas A. Is there an association between cytomegalovirus and renal artery steno-sis in kidney transplant recipients? (abstr). Transplantation 2000; 69: S386.

17. Becker BN, Odorico JS, BeckerYT, et al. Peripheral vascular disease and renal transplant artery stenosis: a reappraisal of transplant renovascular disease. Clin Transplant. 1999; 13(4): 349-355.

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18. Peregrin JH, Stbrn J, Lcha J, Skibov J. Long-term follow-up of renal transplant patients with renal artery stenosistreated by per-cutaneous angioplasty. Eur J Radiol.2008 Jun;66(3):512-8.

19. Henning BF, Kuchlbauer S, Bger CA, Obed A, Farkas S, Zlke C, Scherer MN, Walberer A, Banas M, Krger B, Schlitt HJ, Banas B, Krmer BK. Percutaneous transluminal angioplasty as first-line treatment of transplant renal artery stenosis. Clin Nephrol. 2009 May;71(5):543-9.

20. Patel NH, Jindal RM, Wilkin T, et al. Renal arterial stenosis in renal allografts: Retrospective study of predisposing factors and out-come after percutaneous transluminal angioplasty. Radiology 2001; 219: 663-667.

21. Valpreda S, Messina M, Rabbia C. Stenting of transplant renal artery stenosis: outcome in a single center study. J Cardiovasc Surg (Torino). 2008 Oct;49(5):565-70.

22. Marini M, Fernandez-Rivera C, Cao I, Gulias D, Alonso A, Lopez-Muiz A, Gonzalez-Martinez P. Treatment of transplant renal artery stenosis by percutaneous transluminal angioplasty and/or stenting: study in 63 patients in a single institution. Transplant Proc. 2011 Jul-Aug;43(6):2205-7.

23. Matalon TA, Thompson MJ, Patel SK, Brunner MC, Merkel FK, Jensik SC. Percutaneous transluminal angioplasty for transplant renal artery stenosis. J Vasc Interv Radiol 1992; 3:55-58.

24. Greenstein SM, Verstandig A, McLean GK, et al. Percutaneous transluminal angioplasty: the procedure of choice in the hyper-tensive renal allograft recipient with renal artery stenosis. Transplantation 1987; 43: 29-32.

25. Grossman RA, DafoeDC, Shoenfeld RB, et al. Percutaneous trans-luminal angioplasty treatment of renal transplant artery stenosis. Transplantation 1982; 34: 339-343.

26. Benoit G, Hiesse C, Icard P, et al. Treatment of renal artery ste-nosis after renal transplantation. Transplant Proc 1987; 19(5): 3600-3601.

27. Rundback JH, Sacks D, Kent KC, et al. Guidelines for the reporting of renal revascularization in clinical trials. J Vasc Intervent Radiol 2003;14:477-492.

28. Gray DW. Graft renal artery stenosis in the transplanted kidney. Transplant Rev 1994; 8: 15-21.

29. Beecroft JR, Rajan DK, Clark TW, Robinette M, Stavropoulos SW. Transplant renal artery stenosis: outcome after percutaneous intervention. J Vasc Interv Radiol 2004; 15: 1407-1413.

30. Opelz G, Dhler B: Improved long-term outcomes after renal transplantation associated with blood pressure control. Am J. Transplant 2005; 19:.181-192.

102.4Should we treat post-biopsy arteriovenous fistulas? If so - how?M.R. Sapoval1, O. Pellerin1, E. Thervet2;1Interventional Radiology, Hopital Europen Georges Pompidou, Paris, France, 2Nephrology, HEGP, Paris, France.

Learning Objectives1. To review imaging assessment of AV-fistulas2. To review clinical relevance of AV-fistulas and indications for IR for

AV-fistulas3. To review technique, results and complications of IR for AV-fistulasBecause acute rejection episodes and chronic allograft nephropa-thy are often subclinical without causing a measurable decrease in renal function, there are more and more renal biopsies performed regularly to assess kidney pathology along time ( protocol biop-sies ) (1). Unfortunately, this results in frequent iatrogenic arterio venous fistula, as found in a recent work published in 2008. From 2824 biopsies, an AVF was observed in the follow-up in 8.3 % of patients (2). The management is dictated by the clinical presenta-tion, while one should always remember that approximately 77 % of them disappear spontaneously (2). In the acute setting, clinical

presentation can be perirenal hematoma, gross hematuria, a bruit or thrill accounting for an arterio-venous fistula. In the long-term sec-ondary rupture of a pseudo aneurysm, cardiac failure due to high-flow fistula or progressive renal failure due to a steal phenomenon can be observed. From a pathological point of view, the most com-mon finding are AVF but other lesions can be as well observed, with a lower frequency. These findings can be a false aneurysm and / or an arterio-caliceal fistula (3) Arterio-caliceal fistula even if they likely exist in 100 % when hematuria is present, are seldom demonstrated using imaging because there flow is slow and they may be intermit-tent. Pseudo-aneurysms are more frequent and are caused by hem-orrhage triggered by biopsy-induced damage of the arterial wall. In the course of repair, the endothelium is dissolved leaving a sac con-tinuous with the endoluminal space (4). Most of them spontane-ously thrombose but larger one (> 6 ml i.e. 2.25 cm in diameter) will require treatment by embolization as the risk of rupture is increased at this size (4, 5). The management is decided as a function of clini-cal and anatomical parameters. The indication of embolization is not always easy to retain. In case of acute bleeding, embolization should be performed if the bleeding is life or graft threatening. If the bleed-ing is mild, and the patients have only mild symptoms, a watchful protocol should be proposed. Spontaneous cessation of the bleed-ing can occur and regular duplex US should be performed in addi-tion to the routine clinical follow-up. As described earlier, in case of pseudo-aneurysm, it is the size of the growth rate of the pseudo aneurysm that will mandate embolization. Large (6ml) pseudo aneu-rysms should be embolized while small ones can be managed by simple repeated surveillance. When an AVF is discovered during the work up of a progressive deterioration of the renal function, the indi-cation for embolization should be discussed as a function of the size and hemodynamicity of the fistula . Careful discussion of the indica-tion is of importance because embolization carries the risk of renal infarction as it is not always possible to close the fistula without los-ing some side branches and some kidney parenchyma. In addition, embolization requires using of iodine contrast media that can in itself increase the renal failure. The discussion of the role of the AVF in the deterioration of renal function lies on the potential steal of the renal blood flow from the nephron into the draining vein. Therefore, assessing the hemodynamicity of the AVF is very important. It has been proposed that color duplex ultra-sound can play a role in assessing the relevance of an AVF. The comparison of the main renal artery resistive index (RI) compared with that of the non-AVF associ-ated segmental arteries has a good chance of identifying the hemo-dynamic relevance of an AVF (2). Because of early venous drainage in the fistulized arteries, the tissue is underperfused, explaining renal failure (so called steal phenomenon). While in the main renal artery the RI is at least 0.05 higher than in segmental artery, this number is not approached compared with the non-AVF associated segmental normal arteries. Schwartz tested this sign in 4 patients and correctly predicted the success of coiling in all 4 cases (2). In other words, if a patients presents with an isolated AVF with no other finding, RI mea-sures should be performed. If the main renal artery RI is not at least 0.05 higher than RI in the non-fistulous segmental branches, then hemodynamic relevance of the fistula should be retained and embo-lization should be performed with a good chance to improve renal function. Other indications which are seldom present can be hyper-tension by a steal phenomenon that will trigger renin secretion in the ischemic kidney or high-output cardiac failure. The strategy for embolization should follow certain basic rules. First, one should understand that because the biopsy needle will traverse a relatively large amount of tissue, multiple lesions are frequent. This translates into the need of careful assessment of the angio-anatomy and in the need to always check by a global angio with injection into the main renal artery trunk at the end of embolization to make sure that the lesions have all been treated. This is particularly relevant in the acute setting where all AVF and all pseudo-aneurysm should be treated. Usually, the fistula has a caliber large enough to contraindicate the

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use of liquid or particulate embolics (spheres of PVA). The most fre-quent material to be recommended are fibered coils and gelfoam. In order to spare as much as possible the RT, microcatheter approach is mandatory in order to be as selective as possible. The use of detach-able coils can be of great interest at least for the first coil in order to avoid embolization through the fistula into the venous circulation (6). Packing of a pseudo-aneurysm is not necessary and represents more a waste of time and money. Once the fistula has been success-fully occluded, a selective angiographic control into the main renal artery is needed in order to rule out the presence of another fistula or pseudo-aneurysm that the initial control may have missed (often, the main fistula will steal the flow of contrast and will not allow to depict all fistula). A common trap is also the presence of more than one main artery and the whole kidney inflow should be carefully assessed using multiple injections and projections. Technical suc-cess rate is around 90 % and clinical success rate has been reported in small series between 60 and 90 % (2,6,7) In brief, a small AVF with no clinical consequence discovered incidentally will not need any treatment while a large one with acute severe bleeding will mandate emergent embolization. Patients presenting with a an AVF should undergo duplex measurements of RI and in case of an RI in the main renal artery not reaching the level of the RI in a normal segmental arteries + 0.05; embolization should be performed in case of renal failure with the aim to improve renal function indication for embo-lization. Only in specific cases the embolization will be turned down because of clinical conditions.References1. Morath C, Ritz E, Zier M. Protocol biopsy: what is the ratio-

nale and what is the evidence. Nephrol Dial Transplant 2003; 18:644-647.

2. Schwarz A, Hiss M, Qwinner W, Becker T, Halier H, Keberle M Course and relevance of arteriovenous fistulas after renal trans-plant biopsies. Am J Tranplant 2008;8:826-831.

3. Korbet SM. Percutaneous renal biopsy. Semin Nephrol 2002;22: 254-267.

4. Rivera M, Villacorta J, Jimenez-Alvaro S, Quereda C. Asymptomatic large extracapsular renal pseudoaneurysm fol-lowing kidney transplant biopsy . Am J Kidney Dis 2010; 57: 175-178.

5. Dzinish C, gloviczki P, McKusick MA et al. Surgical management of renal artery aneurysm. Cardiovasc Surg 1993; 1: 243-247.

6. Pappas P, Constantinides C, Leonardou P et al. Biopsy related hemorrhage of renal allograft treated by percutaneous super-selective renal artery embolization. Transplant Proc 2006; 38:1375-1378.

7. Morse SS, Sniderman KW, Strauss EB, Bia MJ. Post biopsy renal allograft arteriovenous fistula. Therapeutic embolisation. Urol Radiol 1985; 7:161-164.

Special SessionMedico-legal issues and IR

103.1Medico-legal aspects of off-label use of IR devicesR.G. McWilliams;Dept. of Radiology, Royal Liverpool University Hospital, Liverpool, United Kingdom.

Learning Objectives1. To discuss what constitutes an off label use of an IR device2. To give examples of off label IR device use3. To discuss the consequences of off label use of IR devicesOn-label use of a product requires that devices and drugs are used for the correct indication, in the correct anatomy, in the method described in the Instructions For Use (IFU), using the recommended

ancillary products. However, modern IR has been largely built on innovation and imagination since Charles Dotter performed the first angioplasty. Every case in IR provides a slightly different tech-nical challenge and procedural success may require the off-label use or modification of a medical device and interventional radiologists pride themselves on their innovative skills and ability to use a device in a different way to achieve their aims or get themselves out of trou-ble. However, there are serious unexpected potential consequences of modifying medical devices, and UK physicians are warned that following modification of a CE-marked medical device, the health-care organization and/or professional could be deemed to be the manufacturer of a new device and may therefore be subject to the requirements of the Medical Devices Regulations. Despite these warnings, audit has shown that off-label use and device modifica-tion are common in IR. But radiologists should be very concerned about any and all off-label device usage in their practice. Good prac-tice dictates that the IFU for all devices and drugs used should be read. Radiologists should distinguish between established and non-established off-label use but often this cannot be clearly defined. In the absence of specific advice from national bodies and profes-sional societies, it is left to the individual to decide and, if there is any doubt, to seek the opinion of the risk-management team in their trust. It is time for professional bodies like CIRSE to lobby the indus-try to negotiate the IFU process.References1. Medical devices alert: medical devices in general and non-medi-

cal products. MDA/2010/001 London: Medicines and Healthcare Products Regulatory Agency; January 2010.

2. Good practice in prescribing medicines. Available at: http://www.gmc-uk.org/static/documents/content/Good_Practice_in_Prescribing_Medicines_0911.pdf.

3. Drug Safety Update April 2009, vol. 2 issue 9:6. Available at: http://www.mhra.gov.uk/Safetyinformation/DrugSafetyUpdate/CON087990.

4. Rosch J, Keller FS, Kaufman JA. The birth, early years and future of interventional radiology. J Vasc Interv Radiol. 2003;14:841853.

5. Kaufman JA. Off-label does not mean off-base. J Vasc Interv Radiol. 2008;19:970971.

6. R.C. Zvavanjanja, T.O. Odetoyinbo, P.C. Rowlands, Off label use of devices and drugs in interventional radiology. Clinical Radiology 2012;67:239-243.

103.2Medico-legal aspects of obtaining consentP. Reimer;Radiology, Klinikum Karlsruhe, Karlsruhe, Germany.

Learning Objectives1. To define what is informed consent2. To discuss who should obtain consent3. To discuss what informed consent means from a legal point of

viewWhat is informed consent? Informed consent describes the process explaining a potential pro-cedure to a potential patient with the final step of signing a docu-ment. Informed consent is not the simple act of signing such a for-mal document. The consent forms serve to document the physi-cians individual discussion with the patient. The signature indicates that the patient understands and consents to the specific treatment and procedures that is planned to be performed [1]. Informed con-sent with appropriate documentation must follow institutional pol-icies and comply with applicable national law. Invasive diagnostic or therapeutic procedures require informed consent. Intravenous or other diagnostic contrast media administration typically requires informed consent based on national law [2] [3].

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Who should obtain consent? In all cases requiring informed consent, it is the physician perform-ing the procedure, or other qualified medical personnel assisting the physician, who should talk with the patient, explain the proce-dure, answer all questions, and arrange for appropriate documenta-tion of informed consent. This documentation might take the form of an executed consent form, movie/film document, or a note in the patients medical record. Phone records are possible based on national law. The consent process should include discussion of the anticipated benefits and potential risks of the procedure. Evident alternatives to the procedure should be explained. The patient should have the opportunity of asking questions and discussing the procedure. All questions should be addressed. The physician per-forming the procedure has the final responsibility for addressing the patients concerns and answering the patients questions. Consent should not be obtained in a coercive manner. The same standards apply to obtaining consent from the patients health care represen-tative or legally appointed guardian [2] [3]. Informed consent and appropriate documentation must be obtained prior to the initia-tion of any procedure that is likely to expose the patient to any sig-nificant risks and potential complications, except in emergency sit-uations. When obtaining informed consent for image-guided pro-cedures that may be associated with higher levels of radiation, an explanation of the likelihood and characteristics of determinis-tic injury should also be included in the consent discussion prior to the procedure [3-4]. The estimated radiation dose received by the patient should be recorded in the patients medical record follow-ing the procedure [5]. The SIRCIRSE Guidelines for patient radiation dose management recommend that follow-up should be performed if the cumulative air kerma at the reference point exceeds 5 Gray [2].Briefly, typical components of informed consent include [2].- The purpose and nature of the procedure or treatment.- The method by which the procedure or treatment will be per-formed.- The risks, complications, and expected benefits or effects of such procedure or treatment.- The risk of not accepting the procedure or treatment.- Reasonable alternatives to the procedure or treatment and their most likely risks and benefits.- The right to refuse the procedure or treatment.After the above items are explained and the physician or health care provider is satisfied that the patient understands the procedure and its possible consequences, the informed consent is executed and appropriately documented. Having the patient sign a consent form most commonly does this. The name of the person or his or her des-ignee performing the procedure must appear on the consent form prior to the signature by the patient. A copy of the consent form(s) should be placed in the medical record. In all other situations a note should appear in the medical record that a discussion was held with the patient and that informed consent was obtained. The note should also include the date and time of the discussion, the content of the discussion, and an evaluation of the patients understanding and response to information provided. A copy of any written infor-mational materials given to the patient may also be included in the medical record. Since the patient must be able to understand the risks at the time he or she gives consent, medications that affect the sensorium should be kept at a minimum and ideally not given to the patient less than 4 hours prior to the patients giving con-sent. Chronic pain medications are less likely to affect the senso-rium. No patient should be deprived of adequate pain control for the purpose of obtaining consent [2]. If consent is sought from the patients health care representative, legally appointed guardian, or family member who cannot be physically present to sign the con-sent form before the procedure, informed consent by telephone may be obtained. The discussion should be documented on the consent form with a note that the consent was obtained by tele-phone. In such cases it is advisable to have the discussion witnessed

by a second hospital staff member who signs the form as a wit-ness. The appropriate time for obtaining consent in major proce-dures is advised as more than 24 hr before the planned procedure, to allow the patient time to digest available information and make an informed decision [2] [3]. When a delay in treatment would jeop-ardize the health of a patient, and the patient is unable to give informed consent, an exception to the requirement for obtaining informed consent from the patient is made. If the patient is unable to consent and has a legally authorized representative who is avail-able to consent, the treating physician must obtain the informed consent of the representative. When informed consent cannot be obtained from the patient or from his or her legally authorized rep-resentative, the physician treating the patient should determine the immediacy of the need for treatment. A physician may provide any treatment or perform any procedure immediately required to pre-vent serious disability or death or to alleviate great pain and suffer-ing. During the course of an operation or a procedure, a physician may perform any procedure that becomes necessary because of a condition discovered or arising during the operation or the proce-dure that presents an immediate threat to the life or the health of the patient [4]. The need for immediate treatment is documented in the patients medical record. Documentation includes all infor-mation establishing the nature, immediacy, and magnitude of the problem, and the impossibility of obtaining consent under the cir-cumstances. Any consulting physicians should enter their findings and recommendations in the record. All notes should show the date and time that the determinations were made [5] [6].Legal consequences of informed consentThe consent form has two purposes: to minimize legal liability and, more importantly, to inform the patient. A consent form with-out documentation that specific complications have been dis-cussed would have questionable value [2]. The law applied when exposed to a legal claim also varies among European Nations; how-ever, there are some issues, which are probably consisted among nations. Eventually a lawyer will check for errors or inconsistencies in the patient records and the consent form. The consent document should be available and is often crucial for assessing the chance of a legal claim or for subsequent court decisions. A complete consent form plays an integral role in protecting the physician against claims such as that complications were not explained or alternative therapy was not mentioned. An explained complication puts the physician in a stronger legal position [7]. The legal assessment of a case when a procedure was performed without informed consent or missing components related to a complication is evident. Such a procedure is considered a physical injury to a patient with subsequent poten-tial legal consequences such as a shift in the burden of proof [8-11].References1. Osime, O.C., et al., Current practices and medico-legal aspects of

pre-operative consent. East Afr Med J, 2004. 81(7): p. 331-5.2. ACR, ACRSIR Practice guideline on informed consent for image-

guided procedures. 2011.3. ODwyer, H.M., et al., Informed consent for interventional radi-

ology procedures: a survey detailing current European practice. Cardiovasc Intervent Radiol, 2003. 26(5): p. 428-33.

4. Picard, L., [Medicolegal aspects in neuroradiologic emergencies]. J Neuroradiol, 2004. 31(4): p. 340-6.

5. Temple-Doig, L., et al., Informed consent for vascular interven-tion. N Z Med J, 2005. 118(1221): p. U1630.

6. Iglesias Lepine, M.L., et al., [Informed consent: opinions of health care personnel from a teaching hospital]. Rev Clin Esp, 2007. 207(10): p. 483-8.

7. Godinho, A.M., L.H. Lanziotti, and B.S. de Morais, Informed consent: the understanding of lawyers and courts. Rev Bras Anestesiol. 60(2): p. 207-14, 119-123.

8. Eufinger, H. and J. Lehmbrock, [Life threatening and fatal com-plications of radical neck dissection]. Mund Kiefer Gesichtschir, 2001. 5(3): p. 193-7.

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9. Klein-Weigel, P., et al., Proximal deep venous thrombosis follow-ing PTA of the superficial femoral artery--an obligation to dis-close a complication that is rarely taken into account. Vasa, 2006. 35(1): p. 41-4.

10. Lydiatt, D.D., Medical malpractice and facial nerve paralysis. Arch Otolaryngol Head Neck Surg, 2003. 129(1): p. 50-3.

11. Racz, I., S. Rejchrt, and M. Hassan, Complications of ERCP: eth-ical obligations and legal consequences. Dig Dis, 2008. 26(1): p. 49-55.

103.3Strategies to minimise complications: safety check listM.J. Lee;Department of Radiology, Beaumont Hospital, Dublin, Ireland.

Learning Objectives1. To provide background to the safety checklists2. To describe the construction of a safety checklist3. To discuss the use of a safety checklistIt has been estimated that there is a one in three million chance of an accident occurring in an aeroplane, while the chance of an acci-dent happening in a hospital is one in three hundred. This is a rel-atively frightening statistic and generally related to systemic issues within hospitals. Often there is a direct link between hospi-tal mortality and practices such as appropriate training, patient appraisal and teamwork. Adverse events damage the credibility of the health system and make society question the performance of the health system. Most enquiries into adverse events identify the same common causes, i.e. poor communication, inadequate lead-ership/management, disempowerment, ineffective systems pro-cesses and isolation. European data consistently shows that medi-cal errors and healthcare-related adverse events occur in between eight and twelve per cent of hospitalisations. Lessons can be learnt from the aviation industry where safety has be an integral compo-nent since its inception. Although there are many factors that may cause aircraft disasters, the aviation industry has worked hard on reducing human factors such as pilot errors. Because there are so many instruments on board, a pilot safety checklist was introduced approximately thirty years ago. The safety checklist is completed before every flight and ensures against pilot error. Recently, a surgi-cal safety checklist was introduced (2009). This WHO surgical safety checklist caused a significant decrease in both morbidity and mor-tality on a worldwide basis in one particular study. Although com-plications are less frequent in interventional radiology, the increas-ing complexity of procedures and increasing numbers of patients with serious co-morbidities make the development of complications more likely. Because of this, CIRSE has developed an IR patient safety checklist to help decrease the human error factor in the develop-ment of complications. The first section deals with procedure plan-ning and covers such aspects as contrast material allergy, abnor-mal renal function, coagulation results and anticoagulation medi-cation. The second section is designed to be completed when the patient comes for the procedure. It deals with immediate checks that should be performed when the patient is in the interventional radiology suite. This includes items such as checking that the correct patient is on the table, the correct side has been marked, and the correct access gained. It also deals with whether antibiotics or other drugs are necessary before proceeding. The third section encom-passes the patient follow-up care, tests and appointments, etc. The checklist can be viewed at WWW.CIRSE.ORG. In addition, appropri-ate training, certification and a commitment to life-long learning enhance patient safety. Undoubtedly, continuous medical educa-tion (CME) and re-certification will appear in the next years from all medical specialists in Europe.

103.4How to avoid a lawsuit after a complicationD. Vorwerk1, K. Bosselmann-Vorwerk2;1Institut fr diagnostische und interventionelle Radiologie, Klinikum Ingolstadt, Ingolstadt, Germany, 2Medical Law, Law firm, Ingolstadt, Germany.

Learning Objectives1. To discuss how to deal with a patient and/or family after a compli-

cation develops2. To discuss who should be involved in the communication3. To discuss what happens if legal proceedings occurComplications may occur after percutaneous interventions, not only due to the nature or severity of the procedure but also through mis-takes made by the performing physician. In elective procedures, the major step prior to each intervention is to obtain full informed con-sent from a patient, mentioning all types of complications that may typically occur, even if they are rare. In emergency procedures this may not be possible, but even then - as long as the patient is capa-ble and awake - brief information should be given in order to estab-lish a relation between the patient and the interventional radiolo-gist. Complications may be foreseeable or completely surprising and it is the duty of each performer to try their best to overcome a sit-uation. This includes use of the full range of interventional possi-bilities to solve a difficult situation but requires also to involve sur-geons or specialists from other disciplines in time. After a procedure, a personal relation needs to be continued - of course less in those cases which run well. In-patients should be seen on clinical rounds, follow-up interventions or diagnostic procedures should prefera-bly be done by the same doctor using devices such as ultrasound to rule out false aneurysms, etc. Specific attention should be given to patients who received an intervention as outpatients. They should stay for a couple of hours in a holding area to detect early compli-cations. When leaving the hospital, they need to be provided with a phone number to contact in time; a letter and images should be pro-vided to them in case they need to be admitted in another institu-tion. In case outpatients phone with complaints, they should ideally be seen by the performing physician as soon as possible. Dealing with them only over the phone without a physical examination is not recommended. In case a complication occurs, the patient needs to be fully informed about what happened, further planned proce-dures and possible outcomes. Again, the same performing physician should try to fix the problem or at least stay until somebody else has fixed it. Early involvement of surgeons, anesthetists or special-ists from other disciplines is mandatory to help the patient to over-come a problem as comfortably as possible. In cases of severe com-plication - if the patient is no longer conscious or has died due to it - an offensive strategy is always recommended. The doctor should talk to the relatives as soon as possible in person, mentioning the potential source of the unfortunate course. This does not necessarily mean that a doctor needs to blame himself. All necessary legal steps should be taken properly and in time; the hospital authorities may be involved in due time and all necessary information needs to be given to other physicians dealing with the patient in question. Never ever should documents be changed, manipulated or hidden. In dif-ficult situations, a physician needs to be present, showing care and empathy for the patient and his or her relatives and should avoid appearing stressed, unfriendly, arrogant or on the run. Empathy is the form of behaviour patients and their families will honor most. The feeling of being left alone will hurt them most.

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Special SessionEmbolic agents

104.1Coils and plugs: when and howJ.-P. Pelage;Department of Radiology, University Hospital and Medical Center, Caen, France.

Learning Objectives1. To review basic coil types e.g. micro/macro, pushable/detachable,

hydrogel etc.2. To describe the different types of vascular plugs/occluders3. To describe indications for coils/plug use and situations where

they could be used

No abstract available.

104.2Particles: when and howY. Arai;Diagnostic Radiology, National Cancer Center, Tokyo, Japan.

Learning Objectives1. To describe the different types of particles available2. To describe mechanism of action, endpoints and technical speci-

fications of each3. To explain when each particle type might be used1. Principle: particle size and injection technique:To start particle embolization, we should note two fundamental principles in advance. Firstly, the diameter of each target vessel is not uniform even in the same lesion. Second, the commercially avail-able particles have more or less size distribution. Therefore, to per-form embolization with particles safely, the following points should be considered:1) never use particles for lesions with arterio-venous shunting (AV-shunt).2) Start with bigger particles to avoid passage into systemic circulation.However, these need some annotations as follows:1) early venous drainage must be distinguished from AV-shunt under DSA. Early venous drainage is the finding of intra-venous con-trast media passing through terminal capillary vessels where parti-cles never pass through. So we can use particles for cases with early venous drainage.2) Embolization with bigger particles easily leads to proximal embo-lization, which cannot stop the inflow of blood to the target area with feeder communications. Generally, except for simple feeders without communications, embolization with bigger size particles is not successful to occlude target vessels effectively. Many cases are associated with communications between feeding vessels in the tar-get lesion. Smaller particles are recommended for use because they can reach closer to the target terminal vessels, resulting in effec-tive embolization. On the other hand, we should bear in mind that smaller particles always have the risk of passage into systemic circu-lation. To perform embolization with smaller particles, there are two technical points to be followed:1) Inject slowly. If being infused too fast, particles easily flow into the communicating vessels and migrate to the non-targeted vessels.2) Use diluted particle-suspension. If suspension density is thick, the particles aggregate to lead proximal embolization. Usually, the recommended minimum particle size is 75-100 microns for liver and 250 microns in other regions to avoid the risk of particles pass-ing into the systemic circulation. In case some events occur, such as

decrease of arterial oxygen saturation suggesting particles migra-tion into systemic circulation, we should stop injection of particles of the size immediately. As imaging modalities to evaluate particles passing into systemic circulation, pre-procedural scintigraphy with 99m-Tc-MAA, intra-procedural CT and DSA during injection of par-ticle suspension may be employed. Unfortunately, these imaging modalities cannot be carried out as routine procedures; thus there is no perfect modality available at present.2. EndpointThe goal to terminate injection of particles is disappearance of tar-get vessels and/or tumor stains on DSA image. If such image can-not be obtained with some adequate volume of particles, it means the particle size was too small. Additional injection is recommended with bigger sized particles. However, we should also consider the risk for undesirable proximal embolization.3. Handling for safe procedureIf there is no risk of particles passing through into systemic circu-lation, slowly injecting small particles with highly diluted suspen-sion seems to be favorable to achieve better results. However, con-sidering high volume of contrast media and radiation exposure, it is not ideal. To challenge these issues, the following techniques are recommended:1) Prepare half-diluted particle-suspension as parent suspension. (If you want to inject 10 times diluted particle-suspension, prepare 5 times diluted particle-suspension).2) If blood flow velocity does not change, inject parent suspension mixed with the same dose of saline using a small syringe without flu-oroscopic examination. Once per 2-5 times injection, evaluate the blood flow velocity using parent suspension mixed with the same dose of contrast media. During injection, rotating or gently shaking the syringe is always necessary to keep the homogeneous status of particle-suspension.3) When the blood flow velocity becomes decreased, use the parent suspension with the same dose of contrast media, or perform the standard DSA with contrast media. In summary, the keys of emboli-zation with particles are as follows:1) appropriate size selection of particles that can reach closer to the target terminal vessels without passing into systemic circulation.2) Adequately diluted particle-suspension and injection speed to avoid undesirable proximal embolization.3) Injection technique to evaluate blood flow velocity with minimum volume of contrast media and radiation exposure.ReferencesGolzarian J, Sun S, Sharafuddin M (Ed.). Vascular Embolotherapy: A Comprehensive Approach, Vol. 1: General Principles, Chest, Abdomen, and Great Vessels. Springer, April 11, 2006.

104.3Glue and onyx: when and howL. Defreyne;Department of Vascular and Interventional Radiology, University of Ghent, Ghent, Belgium.

Learning Objectives1. To describe the different features and mechanism of action of

glue and onyx2. To discuss indications and contraindications for using both glue

and onyx3. To learn the techniques for using glue and onyx

No abstract available.

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104.4How to avoid non-target embolizationJ. Golzarian;Department of Interventional Radiology & Vascular Imaging, University of Minnesota, Division Head, Minneapolis, MN, United States of America.

Learning Objectives1. To discuss anatomic/technical issues2. To learn how to prevent non-target embolization3. To learn how to deal with non-target embolization

No abstract available.

Special SessionIR in the management of DVT

201.1DVT lysis: how I do itK.R. Thomson;Radiology, Alfred Hospital, Melbourne, VIC, Australia.

Learning Objectives1. To describe the speakers patient selection and indications for

intervention2. To explain the devices the speaker uses for tackling DVT3. To describe the speakers approach in case the primary treatment

attempt failsFor DVT lysis patient selection is important. Recent CVA or sur-gery usually is a contraindication, but localised thrombolysis with careful sequestration of the lytic can be performed. This is not the topic of this abstract. It is assumed there are no contraindications. Thrombus, which is less than 7-10 days is always best although in cases where the need of the patient demands something be done, thrombolysis may be worthwhile for older thrombus. It may need a slightly different method such as angioplasty with or without mechanical devices to obtain a good outcome. Acute DVT below the knee is currently treated with anticoagulation (Heparin followed by Warfarin) and calf compression stockings. Lysis is performed by the patient but it is often incomplete. Acute thrombus above the knee and extending to the pelvis is where the interventional radiologist can change lives. This thrombus should be lysed as soon as possi-ble and as completely as possible to ensure that the venous valves are preserved and the venous flow is normalised. Most patients present with an ultrasound diagnosis. It must include the pelvis. If it does not then it is very worthwhile to perform a contrast-enhanced CT to see what the state of the IVC and pelvic veins is, especially in a left leg DVT in a young female, where the possibility of common iliac vein compression is high (May-Thurner Syndrome). If the throm-bus is purely in the pelvis, a femoral vein access is satisfactory, but in most cases the thrombus extends from the femoral vein and a punc-ture of the popliteal vein is necessary. Puncture of the tibial or pero-neal veins below the knee is only necessary where there is no flow at all from the calf to popliteal vein. Beware of puncture of the short saphenous vein as it sometimes enters the femoral vein instead of the popliteal vein. Unlike arterial thrombus, venous thrombus is of high volume. Generally unless it is localised, rapid lysis is not likely to be successful. For this reason, I prefer to work up the patient dur-ing daylight hours and in late afternoon insert a 6Fr sheath in the popliteal vein under ultrasound guidance and place a long infu-sion catheter into the thrombus with the tip at the upper margin of the thrombus. There are 50cm infusion length catheters for this purpose. An infusion of 1million units of Urokinase and 15k units of Heparin are mixed in one litre of normal saline and infused at 70mls/

hour. This takes about 14 hours and will be finished by 7 am the next day so that the completion thrombolysis can be performed as first case. The dose of Urokinase per hour is 70k units per hour. I almost always place a retrievable IVC filter to prevent pulmonary embolism. The next day preliminary venography can be performed through the infusion catheter, but in more complex cases changing from the 6Fr sheath to an 8Fr angled 55cm guide catheter allows more con-trol and lower volume injections of contrast. It allows aspiration and also a wide range of devices to be used including Angiojet and Trellis devices. These devices can be operated in a way to contain the lytic agent for lysis and then allow aspiration to reduce the total lytic dose to the patient. The angle of the guide catheter also allows rotation during use of the Angiojet so that larger-diameter vessels can be treated more effectively. I use an angioplasty balloon wher-ever there is persistent narrowing and to help fragment remain-ing thrombus. If the iliac veins are irregular or narrow I have a low threshold for stenting. It is better to stent longer than shorter, and at the IVC junction, the end of the stent must be matched to the lateral wall of the common iliac vein, not the medial wall. This pre-vents underplacement and restenosis. Once I have established good flow from calf to IVC, anticoagulation is continued with compression stockings and mobilisation as soon as the popliteal vein puncture has sealed. These patients also benefit from referral to lymphoe-dema specialists as they provide excellent management of soft tis-sue oedema which may persist for several days or weeks. At about 1 month the patients return to have their IVC filter removed from a jugular approach. Counselling about DVT is given as they have a higher incidence of further DVT than the normal population. At this time coagulation studies can be performed to identify any thrombo-philic tendency.

201.2Is mechanical thrombectomy useful or are the devices just expensive toys?J.M. Pulido-Duque;Radilogo Vascular Intervencionista, Hospital General Universitario, Las Palmas de Gran Canaria, Spain.

Learning Objectives1. To describe current mechanical thrombectomy devices 2. To present evidence for the usage of mechanical thrombectomy

devices3. To present evidence against the usage of mechanical throm-

bectomy devices and provide a recapitulatory recommendation

No abstract available.

201.3Update on the trials: lysis vs. anticoagulation; lysis vs. throm-bectomyG.J. OSullivan;Interventional Radiology, U.C.H. Galway, Galway, Ireland.

Learning Objectives1. To present DVT trial results2. To comment on the various DVT trials3. To recommend treatment strategies based on trial resultsDeep Venous Thrombosis (DVT) is the third most common cardio-vascular disease. Current treatment regimens are predominantly aimed at decreasing the risk of formation of embolic thrombi. A more proximal thrombus typically gives rise to more serious com-plications. The purpose of these 15 minutes is to give you up-to-date information on the best available evidence for or against more aggressive interventional techniques of thrombus removal. Defining the problem is essential. This talk refers to proximal DVT, to be more

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specific, iliofemoral (IF-DVT) and above. There is plenty of data avail-able as to how poorly patients with IF-DVT fare with conventional treatment and this will be discussed. In addition there is some data with respect to how patients fare after catheter directed thromboly-sis (CDT), somewhat less data is available post mechanical or more typically pharmaco-mechanical thrombectomy (PMT). There is lit-tle in the literature comparing CDT v PMT. Hopefully attendees will leave with a more thorough grasp of the relatively sparse data on this topic, together with a look forward to the results of the eagerly awaited large trials underway- particularly ATTRACT.

201.4Management of chronic iliac vein and caval occlusionJ.A. Vos1, J.P.P.M. de Vries2;1Interventional Radiology, St. Antonius Hospital, Nieuwegein, Netherlands, 2Vascular Surgery, St. Antonius Hopsital, Nieuwegein, Netherlands.

Learning Objectives1. To illustrate the typical clinical and imaging features of chronic

occlusion2. To describe the common interventional techniques in chronic

occlusion 3. To review current evidence and give management recommenda-

tions based on this evidenceIntroduction: Iliocaval chronic venous occlusion is a relatively uncommon condition that is probably underreported in literature. Presenting symptoms in the chronic patient include pain, swell-ing and/or weakness of one or both legs, and venous ulcerations. Varices on the thoracic and abdominal wall or the inguinal region are frequently present. Dyspareunia caused by vulvar varices may be the presenting symptom. With a higher cranial extent it may cause back pain and even kidney or liver function impairment. It may pres-ent with an acute on chronic deep venous thrombosis.The CEAP Classification of signs and symptoms of chronic venous disease:C0 No visible or palpable signs of venous disease.C1 Telangiectasias or reticular veins.C2 Varicose veins; distinguished from reticular veins by a diameter of 3 mm or more.C3 Edema.C4 Changes in skin and subcutaneous tissue secondary to CVDC4a Pigmentation or eczema.C4b Lipodermatosclerosis or atrophie blanche.C5 Healed venous ulcer.C6 Active venous ulcer.Each clinical class is further characterized by a subscript for the presence of symptoms (S, symptomatic) or absence of symptoms (A, asymptomatic), for example, C2A or C5S. Symptoms include ach-ing, pain, tightness, skin irritation, heaviness, muscle cramps, and other complaints attributable to venous dysfunction. Indications for (endovascular) management are reserved for C2S and in most cases C3 or higher. Several factors may predispose an individual to develop venous occlusion, such as hypercoagulability, inflamma-tion, infection and external compression, either benign or malig-nant. Congenital anatomic variants of the IVC may also predispose to occlusion. Iliac vein occlusion is more common in women than men and much more common in the left vs. the right iliac venous sys-tem. The right common iliac artery (CIA) crosses the left iliac vein as both pass in front of the promontory. Particularly in lean patients the right CIA compresses the left iliac vein leading to a relative obstruc-tion and predisposing for occlusion. This condition is known as May-Thurner syndrome.Management: The traditional management of the disorders is by elastic compression and elevation, combined with anti-coagu-lant therapy. The results, however, have, in many cases, been poor.

Surgical reconstruction carries a significant risk of complications and results in many series have been disappointing. In the 1990s an alternative therapy has emerged to treat chronic long-segment ilio-caval venous occlusions, namely endovascular recanalisation and stenting. This treatment strategy has been proven to be efficacious in the short term, in many cases with a dramatic reduction in symp-toms and a significant increase in quality of life. Several studies have shown very satisfactory results during long-term follow-up.Work up: In our institution the work up of patients with symptom-atic chronic ileocaval venous obstruction includes a full (family) his-tory and physical examination. All patients are referred to a dedi-cated vascular diseases physician to evaluate the presence of any coagulopathy. The imaging work up includes at least a CT of the abdomen and pelvis and a venous duplex ultrasound of both legs. The CT is crucial to identify any external compression for instance by a previously unexpected malignancy, but it also serves to iden-tify any anatomical variant that may have played a causative roll and will inevitably be important for the planned endovascular proce-dure. It is important to have adequate venous contrast filling distal to the diseased segment to establish the site of venous access dur-ing the intervention. A delayed-phase CT may therefore be nec-essary. In some cases an additional venogram is made before the actual intervention.Procedure: Most patients in our series are on oral anticoagulants at the time of treatment. If not then 100 mg/d apirin is prescribed indefi-nitely. During the procedure 5000 IU of heparin is administered iv. The procedure is performed under local anaesthesia. As with all procedures in our angiosuites a peripheral iv drip is installed pre procedurally. As the recanalisation of long-standing venous occlusions entails disrupt-ing intravascular adhesions between the front and back walls, venous recanalisations are generally markedly more painful than arterial reca-nalisations. iv pain medication should therefore be at hand and offered liberally. Some centres perform these procedures under epidural or even general anaesthesia. If the occlusions extend into the common femoral veins, the patient is positioned prone on the angiography table to facilitate access to the popliteal veins, which are punctured under ultrasound guidance. In all other cases, the patient is positioned supine and the femoral veins are accessed bilaterally. In some cases a jugular access may also prove necessary. Phlebograms are made to assess the extent of the disease. Passing of the occlusions is generally performed using a hydrophilic stiff guidewire (Terumo, Tokyo, Japan). A predila-tation with an undersized balloon is performed (8mm). Subsequently, the entire segment is stented using self-expandable large-size stents with a high radial force. In the beginning of our series we used the Wallstent (Boston Scientific, Natick MA), which was the only self-expandable stent available at that time. As this stent has an inher-ently unpredictable foreshortening during deployment, we current-ly use the Sinus-XL stent (Optimed, Ettlingen, Germany) which is avail-able in sizes up to 34 mm. A postdilatation with a large-size balloon is finally performed and control phlebograms are made of the entire out-flow to the right atrium. A satisfactory result is obtained if rapid unin-terrupted outflow is seen and the pre existent collateral varices are not opacified.References1. Delis KT et al. Successful iliac vein and inferior vena cava stenting

ameliorates venous claudication and improves venous outflow, calf muscle pump function, and clinical status in post-thrombotic syndrome. Ann Surg. 2007 Jan;245(1):130-9.

2. Eklf B et al. Revision of the CEAP classification for chronic venous disorders: Consensus statement. J Vasc Surg 2004;40:1248-52.

3. Eklf B et al. Updated terminology of chronic venous disorders: The VEIN-TERM transatlantic interdisciplinary consensus docu-ment. J Vasc Surg 2009;49:498-501.

4. Juhan C et al. Treatment of nonmalignant obstructive ilioca-val lesions by stent placement: mid-term results. Ann Vasc Surg. 2001 Mar;15(2):227-32.

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5. Hartung O et al. Endovascular Management of Chronic Disabling Ilio-caval Obstructive Lesions: Long-Term Results. Eur J Vasc Endovasc Surg 2009; 38, 118e124.

6. Neglen P et al. Balloon dilation and stenting of chronic iliac vein obstruction: technical aspects and early clinical outcome. J Endovasc Ther. 2000 Apr;7(2):79-91.

7. Raju S et al. Obstructive lesions of the inferior vena cava: clin-ical features and endovenous treatment. J Vasc Surg. 2006 Oct;44(4):820-7.

8. Razavi M et al. Chronically occluded venae cavae: endovascular treatment. Radiology 2000; 214:133-38.

9. te Riele et al. Endovascular Recanalization of Chronic Long-Segment Occlusions of the Inferior Vena Cava: Midterm Results. J Endovasc Ther 2006;13:249253.

10. Robbins M et al. Endovascular stenting to treat chronic long-seg-ment inferior vena cava occlusion. J Vasc Surg 2005;41:136-40.

Special SessionPaediatric interventions

202.1Biliary interventions in children: how I do itJ.B. Karani;Dept. of Radiology, Kings College Hospital, London, United Kingdom.

Learning Objectives1. Principles and techniques of biliary drainage2. To review techniques to access the non-dilated biliary tract3. To review outcomes and complications of treatmentMany of the principles of biliary intervention parallel those in the adult population although there are fundamental differences that need to be addressed and understood. The principle differences relate to the range of developmental and acquired biliary disor-ders that present to the interventional radiologist, their relative rar-ity outside specialist paediatric liver centres and the differing pre-sentation of these disorders across neonates, infancy, childhood and adolescence. In addition, the developmental biliary disorders may be part of a more complex developmental disorder of the liver and this may influence the indications and interventional technique. The best example of this complexity is biliary atresia. This may form part of the biliary atresia splenic malformation syndrome where situs inversus, polysplenia, malrotation and caval interruption may be associated anatomical anomalies. A second example is the Caroli malformation which may the presenting pathology of a wider duc-tal plate malformation which could include congenital hepatic fibro-sis and renal cystic disease. A further example of this clinical and anatomical complexity is in premature neonates presenting with the inspissated bile plug syndrome where sepsis, assisted ventila-tion and parenteral nutrition may result in the early presentation of a choledochal malformation or pancreatico-biliary junctional anom-aly which would not normally have declared clinically until later life. In all these clinical scenarios percutaneous biliary intervention may be necessary in diagnosis or as a therapeutic manoeuvre to clear the inspissated bile and relieve the obstructive jaundice. A second group where biliary intervention is required is in those children who have previously undergone reconstructive biliary surgery, princi-pally for these developmental disorders. These children require diagnostic or therapeutic biliary intervention either to diagnose or treat strictures. it may be necessary to clear calculi that have formed as a consequence of these strictures or within dilated ectatic ducts which may form part of the intrahepatic component of the original choledochal malformation. A third group to consider is those chil-dren who have undergone liver transplantation and develop a bili-ary complication. There are modified paediatric surgical techniques

of splitting donor organs followed by implantation of orthotopic segmental or auxiliary grafts in metabolic disorders or acute liver failure. These may present a diagnostic and interventional chal-lenge as percutaneous intervention is the primary management of many complications thereby reserving surgery for where inter-ventional radiology has failed. In paediatric recipients the objec-tive is to maintain normal liver function and optimal quality of life through childhood, into adolescence and adult life. Therefore, the threshold for confirming, excluding or treating a biliary stricture is low and any impairment of graft function with histological features of biliary injury may require investigation with percutaneous cholan-giography. Independent of the pathological disorders is the impor-tance of obtaining informed consent from the parents and the tim-ing and participation of the interventional radiologist in this gover-nance process. A second important and debatable issue is when it is acceptable and necessary to deploy implantable devices such as metallic biliary stents. The principles of the actual technique mirror those in adults. Pre-procedural steps include prophylactic antibiot-ics and adequate hydration. All procedures require a general anaes-thetic with the technique allowing suspended respiration. In most cases of intervention this should be preceded by an MRC. This allows safe planning of the approach under ultrasound guidance. This is of particular importance if there is a dual duct anastomosis as may be the surgical anatomy in left lateral segment grafts where segments II and III may be separately anastomosed to the roux loop. MRC also provides the map of any hidden or undrained biliary segments which may be the important pathological finding and the necessary site for intervention. In the majority of cases the ducts are undilated and measure 2 mms or less. It is therefore often helpful to opacify the ducts with a 23-gauge Chiba needle and leave this in position to intermittently distend the ducts and then use a conventional fine needle introduction system. This will then allow deployment of bal-loons, stents or transhepatic drains as necessary. The potential com-plications also mirror those in adults so fundamental to successful outcome and low morbidity is standardised post procedural after-care and the prompt treatment of these, particularly bleeding and sepsis. This presentation will describe the approach to interventions within the described disorders and will provide guidance not only on technique but also the appropriate indications and importance of consistent selection criteria.

202.2Paediatric percutaneous nephrostomy and ureteric interven-tions: tips and tricksB. Gonalves, M.J. Sousa;Interventional Radiology Department, Instituto Portugus de Oncologia (IPO) do Porto, FG, Porto, Portugal.

Learning Objectives1. To review techniques on how to access the non-dilated system2. To review imaging of the kidney with non-dilated collecting

system3. To describe problems and solutions regarding paediatric

nephrostomyThis presentation will be focused on the applicability of interven-tional techniques to the urinary system with special emphasis in the paediatric patients.Percutaneous Nephrostomy: The majority of nephrostomies are performed in a dilated kidney with significant degree of obstruction depending of the kidney function impairment or infection. In these cases an easy access is using US-guided puncture through a dis-tended calyx. But in some problematic cases, such in the presence of an urinary fistula (vesicovaginal, vesicorectal, uretrovaginal, uretero-enteric or ureterovaginal) or a low degree of obstruction, calyceal kidney puncture may be challenging. In the available literature the success rate ranges from 80 to 95%. Usually, it can be initially made

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by US-guidance with a tri-axial introducer kit (including a 22G Chiba-type needle, a 0.018 guidewire and 6Fr tri-axial catheter). In a sec-ond step fluoro-guidance with contrast agent injection in the caly-ceal system is useful to dilate and confirm correct needle position and to avoid multiple punctures. An alternative technique is to inject air to distend the renal pelvis. A diuretic drug may also be used to induce a transient calyceal dilatation, but usually is not necessa