digital subtraction angiography

Free Powerpoint Templates

Digital Subtraction Angiography

Subhayan Mandal

http://www.powerpointstyles.com/

Free Powerpoint Templates 04/11/2023 2

ANGIO?ANGIO means blood vessel

And angiography is the radiological study of blood vessel in the body after the introduction of iodinated contrast media.

SUBTRACTION?

It is simply a technique by which bone structures images are subtracted or canceled out from a film of bones plus opacified vessels, leaving an unobscured image of the vessels.



WHAT DO YOU MEAN BY DSA

DSA-The acquisition of digital fluoroscopic images combined with injection of contrast material and real-time subtraction of pre- and post contrast images to perform angiography is referred to as digital subtraction angiography



The Portuguese neurologist Egas Moniz,( Nobel Prize winner

1949), in 1927developed the technique of contrast x-ray

cerebral angiography to diagnose diseases, such as tumors

and arteriovenous malformations.

HISTORY

The idea of subtraction images was first proposed by the Dutch radiologist Ziedses des Plantes in the 1935, when he was able to produce subtracted images using plain films.

With the introduction of the Seldinger technique in

1953, the procedure became safer as no sharp devices

need to remain inside the vascular lumen.



HISTORICAL DEVELOPMENT

CONVENTIONAL SUBTRACTION TECHNIQUE

Photographic method used to eliminate unwanted images.No addition of information;only purpose to make diagnostically important information to see.First described by a Dutch radiologist, Zeides des Plantes, 1935.3 conditions:SCOUT FILMANGIOGRAM FILM-CONTRAST NO MOTION OF HEAD



The principles of subtraction are based on the following:The scout film shows the structural details of the skull and the adjacent soft tissue.Angiogram film shows exactly the same anatomic details, if the patient does not move, plus the opacified blood vessels.If all the information in the scout film could be subtracted from the angiogram film, only the opacified vessel pattern would remain visible.

CONTD.



Basic arrangement



DSA machines



Indications

• Non traumatic Subarachnoid Hemorrhage (SAH).

• Arterial dissection or laceration

• Aneurysm• Pseudoaneurysm• Thrombosis.• Arterio-venous malformation

(AVM). • Arterio-venous fistula (AVF).• Tumor vascularity

• Embolisation• Stenting • Thrombolysis • Thrombectomy

Diagnostic Therapeutic



Contra indications

No absolute contraindication.

• Poor renal reserve.

• Deranged coagulogram.

• Allergic to contrast media.



Contrast Media

Blood vessels are not normally seen in an x-ray image, because of low

tissue contrast.

To increase image contrast, contrast agents, which are dense fluids with

elements of high atomic numbers, such as iodine, are injected into a blood

vessel during angiography. Because of its higher density and high atomic

number, iodine absorbs photons more than blood and tissue.

This creates detailed images of the blood vessels in real time.

The first contrast media used for intravascular injection were called high-

osmolar contrast media (HOCM). (osmolality is the measure of the particle

concentration in a solution.)

11



HOCM had osmolarity seven to eight times

higher than plasma. This high osmolarity caused

adverse effects such as pain, endothelial

damage, thrombosis, and increased pressure in

the pulmonary circulation.

Low-osmolar contrast media (LOCM) were first

developed in the 1970's and these helped to

reduce these side effects.

One of the major risks of modern iodine contrast

media is an allergic reaction to iodine.



Non ionic Iso-osmolar contrast media.

30-40% dilution with normal saline.

50 ml of diluted contrast media is enough to

do a standard cerebral angiogram with total 8

projections.

Approx. 5-8 ml diluted contrast / injection.

13



Materials used

Catheters

Arterial sheath

Medicut

Guidewires

Contrast

Connector/100 cm.tubing

Surgical blade

14

Saline

Disposable syringes

Local anesthesia

Heparin

Surgical gloves

Elastoplast



Picard

Pigtail

Sim-1

Cathetars


Free Powerpoint Templates 04/11/2023 16 16

VASCULAR SHEATH

MEDICUT

GUIDE WIRES

ELASTOPLAST STRIPS



CONTRASTANESTHESIA

ANTICOAGULANT

PVA-PARTICLESGEL FOAM



PREPARATION

Appointment time

Nil orally 4-6 hrs.

On trolley

In hospital gown

Groin shave

Records

PTI

18

Should be well

hydrated.

Should void before

procedure.

Peripheral pulses

marked.

I.V line in place.

INFORMED CONSENT

MUST


Free Powerpoint Templates Page 2004/11/2023 20

PROCEDURE

Gaining arterial access.

Selective arterial catheterization.

Image acquisition.

Closure of arterial access.

Post processing

Hard copy

20



During angiography, patients may be sedated to reduce anxiety. Their heart rate and rhythm, breathing, and oxygen saturation are monitored throughout the procedure.Patient clean draped . A local anesthetic is usually used in the area where the catheter is to be inserted, most commonly the femoral artery.First, a small incision given, medicut is inserted into the artery. fluoroscopy is used to guide the needle to the proper position . The needle is then removed after placing guide wire in the artery and vascular sheath is inserted over the guide wire . The catheter is then inserted along the guide wire through the sheath.

22



When the catheter is in the correct position, the wire is pulled out and dye is injected through the catheter.

Images are acquired during contrast injection. Injections can be made directly into the artery of interest

(selective arteriography)

Complications from an arteriogram are very rare, but there is some risk. Most problems that occur can be

detected at the time of the procedure or immediately after the procedure. The artery may be injured at the

puncture site or along the artery where the catheter is passed.

23



COMPLICATIONS

0.16% major complication rate.Local complications: hematoma, vessel laceration, dissection, peudoaneurysm, AV fistula.Systemic complications: contrast reactions, fever, sepsis, dehydration, death.CNS complication: aggravation of preexisting complaints, neurological deficit.

24



POSTPROCEDURAL CARE

After the catheter is removed compression is applied to the puncture site.The patient is asked for bed rest for a minimum of 4 hoursDuring rest patient is monitored and vital sign like peripheral pulse like distal to Puncture are regularly The extremity is also checked for warmth, color, numbness to ensure circulation has not been disrupted.



Oral fluid is given and analgesics are given if required.Special care should be given in case of children and geriatric patient since additional Patience is required. They have given warming blanket to keep the body temp. Normal. Geriatric patient also frequently feel nervous and afraid of falling off the Table ,reassurance and additional care from the technologist will enable the Patient to feel secure and comfortable.


Free Powerpoint Templates Page 27

Cerebro-vascular anatomy as appreciated in DSA

Identification

1.Common Carotid Artery. 2.Internal Carotid Artery. 3.Ascending pharyngeal Artery. 4.Occipital Artery. 5.Superficial Temporal Artery. 6.Middle cerebral Artery. 7.Anterior cerebral Artery. 8.Middle meningeal Artery. 9.Maxillary artery. 10.Facial artery. 11.Lingual artery. 12.External carotid artery. 13.Superior thyroid artery.



Diagnostic usage

• Acom aneurysm



Diagnostic usage

• ACA aneurysm



Diagnostic usage

• MCA aneurysm



Diagnostic usage

• Pcom aneurysm



Diagnostic usage

• Basilar tip aneurysm



Diagnostic usage

• ICA aneurysm



Diagnostic usage

• Arterio-venous malformation



Diagnostic usage

• Arterio-venous fistula



Diagnostic usage

• Tumour vascularity



Coiling of cerebral aneurysms

Therapeutic usage



Therapeutic usage

• Lead pipe embolization



Therapeutic usage

• Gel embolization

• Particle embolization



Therapeutic usage

• Onyx embolization

Onyx HD500 is comprised of 20% EVOH (ethylene vinyl alcohol) copolymer dissolved in DMSO (dimethyl sulfoxide), and suspended micronized tantalum powder to provide contrast for visualization under fluoroscopy.Onyx HD500 (20% EVOH) is an HDE device for the treatment of intracranial, saccular, sidewall aneurysms that present with a wide neck (≥ 4mm) or with a dome-to-neck ratio < 2 that are not amenable to treatment with surgical clipping.Onyx HD500 can also be used in adjunctive therapy with Axium coils and stents.



Therapeutic usage

• Stenting of ICA stenosis



Therapeutic usage

• Thrombolysis



Therapeutic usage

• Thrombectomy



In nutshell


digital subtraction angiography

Health & Medicine