A young adult (mid thirties), a known case of non-specific aortoarteritis (Takayasu’s arteritis) was referred for a CT scan of the Abdomen including a CT Aortogram to rule out mesenteric ischemia.
The inital plain (no IV or oral contrast) CT scan did not show any evidence of abdominal pathology. So a CT Aortogram was done.
The following is the best CT image of thoracic and abdominal wall arterial collaterals that I have seen in a decade of being a radiologist:
The following sagittal MIP image shows complete chronic occlusion of a long segment of the distal Descending Thoracic Aorta (about 10cm, between the red arrows) with reformation of flow via phrenic, paraoesophageal, paravertebral and celiac collaterals (yellow arrows) just proximal to the origin of Celiac Trunk.
The third image (coronal MIP) shows multiple dilated tortuous collateral arteries in the anterior, lateral & posterior Thoraco-abdominal wall: Internal Mammary – Superior Epigastric – Inferior Epigastric anastomosis (red arrow marking the coiled-spring-like arteries within the rectus abdominis muscles on both sides); lateral thoracic – lateral abdominal wall (ilio-femoral) anastomoses (yellow arrows).
Additional findings on CECT were:
- Mild pericardial effusion.
- Enlarged heart with dilated left atrium & concentric LV hypertrophy.
- Asymmetric concentric wall thickening in the Abdominal Aorta with narrow caliber (maximal diameter 9mm).
- Moderate-to-severe ostial stenosis at the origins of Celiac Trunk & Superior Mesenteric artery (60% – 70%).
- Normal Celiac & Superior Mesenteric arterial branches.
- Normal right Renal artery.
- Moderate ostial stenosis (50%) at origin of left Renal artery. Normal distal artery. Accessory left Renal artery to the superior pole of left Kidney.
Diagnosis: Aortoarteritis with chronic occlusion of distal Descending Thoracic Aorta & multiple thoraco-abdominal wall collaterals.
Takayasu arteritis is a granulomatous vasculitis of unknown etiology that commonly affects the thoracic and abdominal aorta. It causes intimal fibroproliferation of the aorta, great vessels, pulmonary arteries, and renal arteries and results in segmental stenosis, occlusion, dilatation, and aneurysmal formation in these vessels. Takayasu arteritis is the only form of aortitis that causes stenosis and occlusion of the aorta. [Reference 1]
Though the disease is prevalent worldwide it is more common in developing Afro- Asian countries and in Japan. An extensive involvement of the aorta is more common than isolated involvement of the small segments. A geographic variation has been noted in the distribution of lesions. Disease of abdominal aorta and renal arteries is more common in our country while in Japan involvement of the thoracic aorta (ascending and descending) is more common, with frequent involvement of arch vessels and low incidence of disease involving the renal arteries. Both radiologically and in autopsy specimens, different types of lesions are noted- stenotic, dilatation, occlusive (due to mural thrombus), aneurysmal, and irregular lesions. [Reference 2]
The median age at disease onset of (29 year) is similar to that seen in Asian countries. This finding is in contrast to the later age of onset (41 years) reported in Europe. Females predominated, as previously reported in most other series of the patients. Males are not exempt, however, and some authors report almost equal occurrence in both sexes. In this study, angiograms were done in all clinically suspected patients of aortoarteritis. Most of the patients showed affection of the abdominal aorta and/or renal artery i.e. type-IV (63.64%) of the proposed classification at the international conference on Takayasu arteritis (Masato Okada et al-2001). Similar angiographic features of Takayasu arteritis have been reported in India, Thailand and Mexico. [Reference 3]
References & Further Reading:
- Takayasu Arteritis: eMedicine article by Robert L Cirillo Jr [Registration may be required. Free]
- Non-specific aortoarteritis: Editorial by J Deshpande in the Journal of Postgraduate Medicine [Free]
- Salkar RG, Parate R, Taori KB, Parate TR, Salkar HR, Mahajan S. Aortoarteritis : A study of 33 central Indian patients. Indian J Radiol Imaging 2003;13:61-6 [Free full text article]
*This blog post was originally published at scan man's notes*