( P=.005). MnDPDP-enhanced MRI appeared to be more accurate than

unenhanced MRI, but this was not significant ( P=.059). The sensitivity of

CTwas 48.4% versus 58.1% for unenhanced MRI ( P=.083) and 66.1% for

MnDPDP-enhanced MRI ( P=.004). The difference in specificity between

procedures was not significant. The per-lesion sensitivity was 71.7%,

74.9%, and 82.7% for CT, unenhanced MRI, and MnDPDP-enhanced MRI,

respectively; the positive predictive value of the procedures was 84.0%,

96.0%, and 95.8%, respectively. MnDPDP-enhanced MRI provided a high-

level diagnostic confidence in 92.5% of the cases versus 82.5% for both

unenhanced MRI and CT. The kappa value for interobserver variability

was N.75 for all procedures.

Conclusions: The diagnostic accuracy and sensitivity of MnDPDP-

enhanced MRI are significantly higher than single section spiral CT in

the detection of colorectal cancer liver metastases; no significant difference

in diagnostic accuracy was observed between unenhanced MRI and

MnDPDP-enhanced MRI.

n 2006 The Royal College of Radiologists. Reprinted with permission.

The incidence of hepatic pseudolesions caused by focal rib compression

as seen on multidetector row CT in patients of different hepatic

function

Nishie A, Yoshimitsu K, Hiroyuki I, Aibe H, Tajima T, Asayama Y, Matake

K, Ishicami K, Nakayama T, Kakihara D, Honda H (Department of

Clinical Radiology, Graduate School of Medicine, Kyushu University, 3-1-1

Maidashi, Higashi-ku Fukuoka 812-8582, Japan). Eur J Radiol 2006;57:

108–114.

Objective: This study aimed to determine whether the incidence of

pseudolesions of the liver caused by rib compression is correlated with

liver function.

Materials and methods: Multidetector row CT images of 150 consecutive

cases were evaluated for the presence of pseudolesions caused by rib

compression. Liver function was categorized into two groups, mainly using

the Child–Pugh classification: Group I—normal liver function and Grade

A; Group II—Grades B and C. The number of focal deformities of the liver

caused by rib compression was also counted. The incidence of pseudole-

sions based on number of patients or focal deformities of liver parenchyma

by rib compression were compared between the two groups.

Results: There were 108 and 42 patients in Groups I and II, respectively;

169 and 41 focal deformities of the liver caused by rib compression were

found in Groups I and II, respectively. Patient-based and deformity-based

incidences of pseudolesions were 10.7% (16/150) and 7.6% (16/210),

respectively. All pseudolesions were seen in patients of Group I. Both

patient-based and deformity-based incidences of pseudolesions were

significantly higher in Group I as compared with those in Group II.

Conclusion: Pseudolesions of the liver caused by focal rib compression

may be seen more frequently in patients with preserved liver function than

in those with impaired function.

Multidetector-row CT of renal arteries: review of the performances in

normo- and hypertensive patients

Coulier B (Department of Diagnostic Imaging, Clinique St Luc, Rue St Luc

8, B-5004 Bouge (Namur), Belgium). J Belge Radiol 2006;88:311–321.

Objective: This study aimed to justify and illustrate the advantages of

multidetector-row CT (MDCT) as probably the most effective method for

imaging renal arteries and to debate the question of multiple renal arteries.

Methods and materials: The renal arteries of 158 hypertensive patients

were investigated with 8-row and 16-row MDCT using a highly stand-

ardized protocol; the results were compared with those obtained in a group

of 112 normotensive patients.

Results: MDCT of the renal arteries was found technically safely

interpretable in 97.4% of cases. Fibromuscular dysplasia was found in

7/156 hypertensive patients (4.66%) concerning 9 arteries (2.18%),

and N50% atherosclerotic stenosis (in terms of reduction of the cross-

sectional area) was found in 11/156 patients (7%) concerning 14 arteries

(3.4%). Accessory renal arteries were found in 66/156 hypertensive patients

(42.3%), implicating 84 kidneys (27%), and in 50/112 patients (44.6%) of

the normotensive group, implicating 67 kidneys (29.9%).

Conclusion: With a good protocol, MDCTof the renal arteries is technically

interpretable in most patients and can safely rule out atherosclerotic stenosis

and/or fibromuscular dysplasia. The systematic cine-review of the native

millimetric reconstructions and volume rendering images are the most

recommendedmethods. Direct axialMPR views of the arterial lumen are also

possible, permitting a precise calculation of the percentage of stenosis from

the cross-sectional area of the artery, an advantage on DSA in cases of

asymmetrical stenosis. Finally, a very high prevalence of multiple renal

arteries — the highest ever reported to our knowledge — is found, and the

prevalence appears similar in both hypertensive and normotensive groups;

this high prevalence not only confirms and emphasizes the very high

sensibility and resolution of MDCT but also definitively disproves the

hypothesis that multiple renal arteries could predispose to hypertension.

A comparison of the diagnostic performance of systematic versus

ultrasound-guided biopsies of prostate cancer

Heijmink SWTPJ, van Moerkerk H, Kiemeney LALM, Witjes JA, Frauscher

F, Barentsz JO (Department of Radiology, Radboud University Nijmegen

Medical Centre, Geert Grooteplein zui 10, NL-6500 HB Nijmegen, The

Netherlands). Eur Radiol 2006;16:927–938.

Transrectal ultrasound (TRUS) is an important tool for urologists and

radiologists in the detection of prostate cancer. Various TRUS-guided

biopsy techniques are applied in clinical practice. Frequently, only the

detection rates achieved with these methods are compared. Other diagnostic

performance parameters, particularly the specificity and negative predictive

value, are seldom compared. After extensive assessment of the available

literature, this review describes the methods of TRUS-guided biopsy for

prostate cancer detection. A distinction was made between systematic

biopsies and biopsies that target a perceived (hypoechoic or Doppler-

enhancing) lesion on imaging. Subsequently, the diagnostic performance

(sensitivity, specificity, positive and negative predictive values, and

accuracies) was compared between these techniques. Imaging-guided

biopsy showed better diagnostic performance than systematic biopsy with

higher sensitivity. The combinations of sensitivity and specificity were

highest for color Doppler and contrast-enhanced targeted biopsy. Studies

targeting hypoechoic lesions had relatively high sensitivity, but specificity

was low. Presently, however, with widespread prostate-specific antigen

screening, fewer prostate cancers are hypoechoic, and the value of targeting

hypoechoic lesions has diminished. Performing color or contrast-enhanced

Doppler biopsy or adding these techniques to systematic biopsies improves

diagnostic performance, particularly by increasing sensitivity.

Transrectal ultrasound-guided prostate biopsy: is antibiotic

prophylaxis necessary?

Puig J, Darnell A, Bermudez P, Malet A, Serrate G, Bare M, Prats J

(Diagnostic Imaging Department, UDIAT CD, Institut Universitari,

Fundacio Parc Tauli, Corporacio Sanitaria Parc Tauli, Parc Tauli s/n E-

08208 Barcelona, Spain). Eur Radiol 2006;16:939–943.

The aim of this study was to assess infectious complications in transrectal

ultrasound-guided prostate biopsy (TRUSPB), comparing two groups of

patients: one group with antibiotic prophylaxis and the other without

prophylaxis. A total of 1018 TRUSPBs were performed from April 1996 to

July 2003. No antibiotic prophylaxis was given in the first 614; the

remaining 404 procedures were performed under antibiotic prophylaxis.

Biopsy complications were assessed at outpatient urologist visits after the

procedure in the 212 first biopsies and by telephone interview in the

remaining 806. A total of 78 infectious complications were found. Major

Abstracts / Clinical Imaging 30 (2006) 372–375374

infectious complications (n =41) were septic shock (n =3), sepsis (n =3),

Fournier gangrene (n =1), urinary tract infection (n =2), and fever requiring

hospital admission (n =32). Minor infectious complications were fever that

did not require admission (n =29), prostatitis (n =6), and epididymitis

(n =2). Infectious complications occurred in 63 of 614 (10.3%) procedures

without antibiotic prophylaxis and in 15 of 404 (3.7%) of those with

antibiotic prophylaxis ( P=.0001). Of the 41 major infectious complica-

tions, 31 (75.6%) occurred in procedures without antibiotic prophylaxis

(n =583) versus 10 (24.4%) in those with prophylaxis (n =394; P=.0410).

In conclusion, transrectal ultrasound-guided biopsy of the prostate has a

statistically significant higher risk of infectious complications when

performed without antibiotic prophylaxis.

CT-guided percutaneous vertebroplasty in the therapy of vertebral

compression fractures

Vogl TJ, Proschek D, Mack M, Hochmuth K (Department of Diagnostic and

Interventional Radiology, University of Frankfurt, Theodor-Stern-Kai 7,

D-60596 Frankfurt am Main, Germany). Eur Radiol 2006;16:797–803.

The purpose of this study was to determine the efficacy and safety of

CT-guided percutaneous vertebroplasty in the treatment of vertebral

compression fractures. The primary objectives were pain reduction and

bone-cement leakage during a long-term follow-up in patients with

osteoporotic vertebral compression fractures. CT-guided percutaneous

vertebroplasty was carried out in 61 patients (mean age, 71.4 years; range,

42–83; female ratio, 73.8%) with vertebral compression fractures. Treat-

ment was carried out on an outpatient basis. Pain, bone-cement leakage, and

complications were monitored and recorded. The mean follow-up time

was 19.8 months (range, 3–52). Paired comparison procedures were used

for the analysis of the results, which showed that all patients had a

significant reduction of pain. The mean visual analogue scale (VAS)

score before treatment was 8.8 points (range, 6.5–9.8 points). The mean

VAS score after treatment was significantly reduced to 2.6 points (range,

1.5–4.1 points; Pb.01). No clinical or neurological complications were

documented. Minor and asymptomatic bone-cement leakage was observed

in 54% of the cases. Percutaneous vertebroplasty is an efficient and safe

interventional procedure that rapidly improves the mobility and quality of

life of patients with vertebral compression fractures. CT guidance is a

reasonable upgrade in the treatment procedure, which reduces the amount

of bone-cement leakage.

Diffusion-weighted MRI of the spine tumors [in French]

Lasbleiz J, Askri A, Le Duff F, Decaux O, Marin F, Duvauferrier R

(Department de Radiologie et d’Imagerie Medicale, Hopital Sud, BP

90347, F-35203 Rennes cedex 2, France). J Radiol 2006;87:480.

Purpose: This study aimed to evaluate the contribution of diffusion-

weighted MR imaging in malignant spine pathology.

Materials and methods: Between February 2004 and January 2005,

49 patients (43 to 86 years old) were included. Three groups were made:

osteoporotic collapses (n =13), malignant collapses (n =15), and malignant

spine lesions (n =21). The MRI (Symphony 1.5 T) allowed SENSE

imaging. After conventional MRI examination (T1, T2 fat sat, T1 with

Gadolinium), all patients underwent diffusion-weighted imaging (Spin

Echo) with variable b values: 0, 250, 500, 750, and 1000. The diffusion

sequence lasted 2 min 29 s. The Apparent Diffusion Coefficient (ADC) was

calculated automatically. The analysis was qualitative (signal study b =1000

mm2/s) and quantitative (ADC measurement).

Results: The image quality was good except for some cervical examinations.

Qualitative analysis did not show a difference between benign and malignant

lesions. Quantitative results are malignant spine lesion (mean ADC=

0.826�10�3 s/mm2), malignant spinal collapses (mean ADC=0.912�10�3

s/mm2), and benign spinal collapses (mean ADC=1.497�10�3 s/mm2).

There were overlapping results between benign and malignant lesion. The

statistical study showed a significant difference (t test with Pb1/10,000). For

anADC threshold value of 1.089 (malignant lesionADCb1.089), ROC curve

showed a specificity of 80% and a sensitivity of 83.3%.

Conclusion: Performing diffusion-weighted imaging of the spine is easy

with new MR technology. The ADC measurement of spine lesion provides

important additional information but does not serve as a substitute for the

routine MRI sequences. In the future, it could become an important point in

this difficult diagnosis.

Radiofrequency ablation of chondroblastoma using a multi-tined

expandable electrode system: initial results

Tins B, Cassar-Pullicino V, McCall I, Cool P, Williams D, Mangham D

(Department of Radiology, RJAH Orthopaedic and District Hospital,

Oswestry, SY10 7AG, UK). Eur Radiol 2006;16:804–810.

The standard treatment for chondroblastoma is surgery, which can be

difficult and disabling due to its apo- or epiphyseal location. Radiofrequency

(RF) ablation potentially offers a minimally invasive alternative. The often

large size of chondroblastomas can make treatment with plain electrode

systems difficult or impossible. This article describes the preliminary

experience of RF treatment of chondroblastomas with a multi-tined

expandable RF electrode system. Four cases of CT-guided RF treatment

are described. The tumor was successfully treated in all but two cases,

wherein complications occurred: infraction of a subarticular chondroblas-

toma in one case and cartilage and bone damage in the unaffected

compartment of a knee joint in the other. RF treatment near a joint surface

threatens the integrity of cartilage and, therefore, long-term joint function. In

weight-bearing areas, the lack of bone replacement in successfully treated

lesions contributes to the risk of mechanical failure. Multi-tined expandable

electrode systems allow the treatment of large chondroblastomas. In weight-

bearing joints and lesions near the articular cartilage, there is a risk of

cartilage damage and mechanical weakening of the bone. In lesions without

these caveats, RF ablation appears promising. The potential risks and

benefits need to be evaluated for each case individually.

Radiological assessment of bone segments for transplantation:

experience at Rizzoli Orthopedic Institute

Tetta C*, Taddia N, Poli T, Quinto C, Fornasari PM, Albisinni U. Eur J

Radiol 2006;57:115–118.

Aim: This study aimed to analyze results obtained from radiological

assessment of skeletal segments stored in the musculoskeletal tissue bank at

Rizzoli Orthopedic Institute.

Materials and methods: Between January 1997 and June 2003, 891 bone

segments underwent radiographic examination in two views. Two hundred

thirteen of these segments were examined by a radiologist between July

2002 and June 2003. Diagnostic evaluation was aimed at recognizing

relevant degenerative, traumatic, and focal lesions. Focal lesions underwent

histological tests.

Results: Twenty-two lytic lesions were found in 12 segments. Ten of these

were studied between July 2002 and June 2003 and two in the period before

specialist radiological assessment. In the latter cases, the lesions were

identified by the orthopedic specialist who had examined the X-rays before

planning surgery. Histological tests showed that the bone tissue was normal

or involved in degenerative phenomena.

Conclusions: We think that donor screening should include radiological

assessment of bone segments, performed according to standard parameters

by a radiologist to identify bone lesions that may jeopardize the successful

outcome of surgery.

* E-mail address: ceciliatetta@katamail.com.

Abstracts / Clinical Imaging 30 (2006) 372–375 375