PMC4722519_01
Axial computed tomography head (a and b) showing a hemorrhage in the prepontine and interpeduncular cisterns with mass effect on the brainstem from the left superior cerebellar artery aneurysm, demonstrated on coronal computed tomography angiography (c and d)
SNI-7-36-g001.jpg
PMC4722519_01_SNI-7-36-g001.jpg
F1
A healthy 51-year-old male presented to our institution with a headache, complete left oculomotor nerve palsy and increasing lethargy secondary to a ruptured 10 mm left proximal superior cerebellar artery (SCA) dissecting aneurysm with the two branching vessels emerging from its distal aspect [Figure 1].
Anteroposterior view of left internal carotid artery injection digital subtraction angiograph (above), demonstrating left superior cerebellar artery aneurysm and bifurcating branches emerging from the aneurysm dome. Three-dimensional reconstruction of aneurysm complex (below)
SNI-7-36-g002.jpg
PMC4722519_01_SNI-7-36-g002.jpg
F2
A cerebral angiogram was performed to better characterize the aneurysm's morphology [Figure 2].
Intraoperative microscopic view of aneurysm complex viewed during left subtemporal approach (right = anterior, up = inferior) (above). Identical intraoperative view during indocyanine green videoangeography after applying temporary clips proximally on the branches of the superior cerebellar artery (below). Smaller branch (*) is seen fluorescing, while larger branch (**) and aneurysm dome (#) are not seen. The location of these nonfluorescing structures is outlined in white
SNI-7-36-g003.jpg
PMC4722519_01_SNI-7-36-g003.jpg
F3
Using intraoperative ICG videoangiography, we found that the smaller of the two SCA branches had retrograde flow while the larger did not, indicating a lack of collateral flow into the larger SCA branch [Figure 3].
Postoperative axial computed tomography angiogram demonstrating complete clip occlusion of the left superior cerebellar artery aneurysm. A single clip was placed proximal to the aneurysm and one clip was placed proximally on each of the distal branches (left). The superficial temporal artery (arrow) is patent and feeding into the patent larger superior cerebellar artery (arrowhead) branch (right). No cerebellar infarcts were noted on postoperative imaging
SNI-7-36-g004.jpg
PMC4722519_01_SNI-7-36-g004.jpg
F4
A postoperative CTA demonstrated patency of the bypass and no residual filling of the excluded dissecting aneurysm [Figure 4].