Anterior spinal artery aneurysm in aortic stenosis of different etiology: Report of three cases

Abstract

Isolated aneurysms of spinal arteries are rare. Spinal artery aneurysms are commonly found in association with spinal cord arteriovenous malformation and coarctation of aorta and rarely with aortic arch interruption and Klippel-Trenaunay syndrome. Spinal angiograms are the gold standard for diagnosing these spinal artery aneurysms but with the advances in computed tomography technology these aneurysms can also be very well demonstrated in computed tomography angiograms. We describe three cases of anterior spinal artery aneurysm, those are flow related aneurysms, associated with coarctation of aorta and with Takayasu arteritis.

Keywords: Anterior spinal artery; Takayasu arteritis; aneurysm; coarctation of aorta; computed tomography angiography.

Figure 1.

Sagittal T2 weighted image (T2 WI) of the cervical spine shows acute subarachnoid hemorrhage (SAH) causing cord edema at lower cervical level. (a) Multiple flow voids are also seen in lower cervical and upper dorsal spinal canal. (b) SAH also noted in lumbar canal.

Figure 2.

Sagittal and coronal reconstruction MIP images of computed tomography (CT) angiogram. (a) Significant focal narrowing of the proximal descending thoracic aorta is noted 3.8 cm after the origin of the left subclavian artery. (b) The anterior spinal artery (ASA) is dilated and a small aneurysm is seen at the upper border of C7. (c) The dilated ASA joins to the radiculomedullary artery at D4 level and the aneurysm is visualized more clearly (arrow in (c)). MIP: maximum intensity projection.

Figure 3.

Sagittal T2 weighted image (T2 WI) of the dorsal spine shows hyperintense subacute subarachnoid hemorrhage (SAH) causing adjacent cord edema. Some flow voids are also noted in the lower dorsal canal.

Figure 4.

(a) NCCT thorax and abdomen, sagittal reformatted image demonstrates wall thickening and calcification involving thoracic and abdominal aorta. (b) Computed tomography (CT) angiography reveals focal tight stenosis involving infrarenal aorta. Collateral channels seen communicating the anterior spinal artery with aorta caudal to the obstruction through the radicular arteries ((b), (c) and (d)). A small aneurysmal outpouching from anterior spinal artery is seen at the level of upper border of D5 (arrow in (d)). NCCT: Non contrast CT.

Figure 5.

Magnetic resonance imaging (MRI) and DSA in Case 3. (a) Saggital and (b) axial T2 weighted MRI shows a well-defined rounded hypointense lesion anterior to the spinal cord at D1 level compressing the spinal cord posteriorly. Increased signal intensity noted in the spinal cord at D1 and D2 level. Dilated flow voids are also noted cranial to the lesion as well as in the pre and paravertebral region. (c) DSA shows the spinal aneurysm and multiple dilated collateral channels. DSA: digital subtraction angiography.