Ultrasound / Interventional Radiology
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CURRENT PATHOLOGY IMAGING GUIDELINES
A. Neck and thorax
B. Upper abdomen
C. Genitourinary system
D. Vascular system
- deep venous
- aneurysm of
the abdominal aorta
of a peripheral artery
and posttraumatic haemorrhage
E. Central nervous system
H. Nuclear Medicine
- vascular calcifications (aneurysm of the aorta,
arteriosclerosis, diabetic angiopathy), complications (atrophy,
- preoperative work-up (detailed anatomy, collaterals)
- allows consecutive interventional procedures (dilatation,
- pulmonary embolism (only if at least one positive previous
test such as Doppler, scintigraphy, D-dimers)
- arteriovenous malformations, mycotic aneurysm
- contraindications: cardiovascular instability, ventricular
arrhythmia, left bundle-branch block, severe pulmonary hypertension,
allergy to contrast media, myeloma, unstable diabetes, renal failure.
Digital substraction intravenous angiography:
- no arterial puncture, easier to perform
- less anatomical detail, unforeseeable picture quality,
necessity of high volumes of contrast medium.
- imaging of recent and older thromboses if Doppler
ultrasound unconclusive. May fail to opacify some deep veins.
- preoperative work-up: integrity of the deep venous network,
good depiction of the perforating and varicose veins.
- morphological analysis of the vessel (arteries: stenosis,
atheroma, dilatation, thrombus / veins: compressibility of the vessel,
- Color Doppler visualization of the flux in real time
(stenoses, accelerations and decelerations, demonstration of
pseudo-/aneurysms and of arteriovenous fistulas)
- Power Color Doppler ("energy", "angiographic") : the signal
is not depending on the angle of ultrasound incidence, whence better
visualization of the vascular tree of an organ or of a vessel in a
- Pulsed spectral Doppler: direction and speed of the flow,
haemodynamic profile of a stenosis, of intraparenchymatous vessels
- Continuous spectral Doppler: more sensitive to slow flow
than pulsed Doppler, but doesn't show direction of the flow, doesn't
explore a definite volume, no ultrasound images
ultrasound after intravenous contrast medium: higher vascular Doppler
signal in difficult cases; easier parenchymal lesion depiction with
cinetic study possibility.
- isometric acquisition with 3D volumic reconstruction (renal arteries, coeliomesenteric
vessels, polygon of Willis, carotids)
- highly calcified vessels are more difficult to image
- several complementary techniques, 2D and 3D. Artery
calcifications don't influence image quality
- no X-rays, no iodinated contrast medium (often IV
- adequate patient collaboration necessary
- spatial resolution is a little lower than with angioCT
- artifacts may sometimes cause under- or overestimation of a
stenosis. May miss very small intracranial aneurysms.
1. Deep venous thrombosis
- EchoDoppler: DVT, ruptured popliteal cyst, abscess
or hematoma of the calf, panniculitis, fasciitis, aneurysm or
thrombosis of the popliteal artery. Allows to rule out a thrombosis
from the iliofemoral to the popliteal level. Thrombosis of calf veins,
- CT angiography or phlebography if Doppler inconclusive
- D-dimers sampling (very sentitive but not specific)
2. Arterial acute obstruction
- Arteriography (vital organ or threat of necrosis):
preoperative work-up; allows interventional procedures or a local
- EchoDoppler in most other cases
- CT angiography, MR angiography.
3. Arterial ischemia
- EchoDoppler: visualization and measurement of
stenoses, atheroma plaque, aneurysms, steal syndrome (subclavian),
reversal of flow. Applications: carotids, extremities, abdominal
vessels, cerebral arteries (transcranial, transfontanellar Doppler)
- MR angiography: more precise work-up
- Angio-CT: same as MRI, but lower sensitivity for carotid or
vertebral artery dissection
- Arteriography: to perform angioplasty, as preoperative
work-up or for traumatic lesions.
4. Aneurysm of the abdominal aorta
- EchoDoppler: allows to rule out an aneurysm.
Demonstrates the dilatation, the wall thrombus, the remaining aperture;
less reliable than CT to rule out fissuration of the wall. Fairly high
risk of rupture if diameter > 5 cm.
- CT (and angio-CT): more precise diagnosis (inclusion
of the renal arteries in the aneurysm, abdominal organ ischemia, signs
- MR angiography
- Arteriography: preoperative work-up
5. Dilatation of a peripheral artery:
- Color and pulsed EchoDoppler: aneurysm, ectasia,
arteriovenous fistula. Haemodynamic downstream repercussion.
Compression treatment of an iatrogenic pseudoaneurysm (after arterial
- MR or CT angiography
- Arteriography: preoperative work-up, stent placement.
6. Lower extremities edema:
- EchoDoppler: abdominal masses compressing the iliac
or caval veins. Thrombosis. Cardiogenic central venous stasis. Ascitis.
- CT: complementary to echography
- MRI: tumoral thrombus extension
- Cavography: usually performed at the time of caval filter
7. Abdominal vessels:
- EchoDoppler: portal hypertension (aspect of the
liver, spleen, ascitis, collaterals, flow inversion of portal, superior
mesenteric & splenic veins, portal thrombosis, portocaval shunt
follow-up); Budd-Chiari, thrombosis of a renal vein, mesenteric artery
stenosis, arcuate ligament compression, arterial thrombosis (mesenteric
infarct), systemic hypertension (see renovasular hypertension).
- CT (if necessary, angio-CT, MR angiography): problem solving
- Arteriography, portography: problem solving + preoperative
workup; interventional radiology (dilatation, stents, embolisation,
8. Gastrointestinal and posttraumatic
- CT, Arteriography: aneurysm, gastroduonenal ulcer,
diverticulum, Meckel, arteriovenous malformation, angiodysplasia,
tumor. Extravasation visible only if active bleeding > 0.5 ml/min.
Selective embolisation possible.
- Scintigraphy: search of Meckel, locates bleeding
source if oozing > 0.5 - 0.05 ml/min.
- If subacute, digestive examinations: endoscopy,
videocapsule endoscopy, CT
colonography, barium enema/meal (not to be done before angiography),
- EchoDoppler, CT: portal hypertension staging (oesophagial
Pierre Bénédict, MD, FMH radiologist, Lausanne,