This middle-aged man presented with acute back pain, followed quickly by lower extremity paresis, sensory level, and incontinence — typical spinal hemorrhage presentation. Notably, nonhemorrhagic spinal artery infactions present in the same manner — onset is usually painful, even when there is no bleeding — unlike most cerebral ischemic infarcts.
MRI of the thoracic spine shows an intradural, extramedullary hematoma (orange arrows), which is best seen when outlined by a normal ventral spinal vein (light blue) on post-contrast T1-weighted images.
Injection of the right T10 segmental artery identifies a typical fusiform dissecting aneurysm (red) of the radiculomedullary artery (Adamkiewicz, pink), giving rise to the anterior spinal artery (purple). Most isolated spinal aneurysms (isolated meaning not associated with artiovenous shunts such as AVMs or intradural fistulas) are ruptured dissections (i.e. ruptured dissecting aneurysms or pseudoaneurysms). The catheter arrow is black, and dorsal division of the segmental artery is yellow
Fortunately, another sizable contribution to the anterior spinal axis was located from the right T7 segmental artery. With the microcatheter wedged in the right T10 level proximal radiculomedullary artery (white arrow), thus obstructing its flow (test occlusion), the right T7 segmental artery is injected through a second diagnostic catheter. You can see robust reconstituion of the entire spinal axis, including the portion below T10. Therefore, the patient “passed” test occlusion, enabling sacrifice of the right T10 radiculomedullary artery with coils (green arrows). Notice that coils do not reach the level of the pseudoaneurysm. We felt this to be acceptable, as no other branches arise from the T10 radiculomedullary artery to enable its continued patency. With no outflow, the artery and its dissecting aneurysm will thrombose. In fact, the post-coiling image on the right no longer opacifies the dissecting pseudoaneurysm. The patient recovered well and has not re-hemorrhaged.
CASE 2 — Adamkiewicz aneurysm
Once again, the aneurysms appear to have a predilection for the intradural portion of the radiculomedullary artery. The reason for this, as far as i am aware of, is unknown. The location is quite distal to the vessel’s entry tru the dura, and therefore mechanical / frictional / dissecting mechanisms by which the aneurysm would develop are hard to support.
This post-partum patient presented with back pain, followed by complete sensory, motor, and autonomic deficit below the waist. MRI demonstrates extensive blood products in the intradural space, what seems like a dorsal epidural collection at the upper thoracic level (black arrow) and a discrete oval lesion at T11 level (white arrows) which is extramedullary. Is it indradural or extradural?
Angiogram demonstrates a partially thrombosed fusiform pseudo=aneurysm of the Artery of Adamciewicz, beautifully (indeed!) seen in this stereo pair
The next closest radiculomedullary artery, at left T7 level, is hopelessly small.
Test occlusion was deemed impractical. The patient was taken to the OR for decompression of intrathecal hematoma. Recovery has been quite partial.
Surgical disconnection of posterior spinal aneurysm, by Carolina Benjamin MD and Anthony Frempong, MD
The same cases, with some more information on spinal aneurysms, can be found on the Spinal Arterial Aneurysm page