Distal Middle Cerebral Artery M4 Aneurysm Surgery Using Navigation-CT Angiography

Abstract

Unruptured non-traumatic dissecting aneurysm in the M4 segment of the middle cerebral artery (MCA) accompanied by complete occlusion of the ipsilateral internal cerebral artery (ICA) has never been reported. A 41-year-old man presented with an infarction manifesting as left-sided weakness and dysarthria. Magnetic resonance angiography revealed a subacute stage infarction in the right MCA territory and complete occlusion of the right ICA. Angiography demonstrated aneurysmal dilatation of the M4 segment of the right MCA. Surgery was performed to prevent hemorrhage from the aneurysm. The aneurysm was proximally clipped guided by Navigation-CT angiography and flow to the distal MCA was restored by superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. We report this rare case with literature review.

Keywords: Dissecting aneurysm; Middle cerebral artery aneurysm; Navigation.

Fig. 1

Cerebral angiogram revealing right internal carotid artery occlusion (A). Anteroposterior angiogram demonstrating aneurysmal dilatation of the M4 segment of the right middle cerebral artery (B).

Fig. 2

Axial view of cerebral perfusion SPECT with acetazolamide challenge showing a lack of vasodilatory reserve in the right middle cerebral artery territory.

Fig. 3

3D-computed tomography angiography reconstructed with 3D imaging software (Philips Brilliance, 64 channel, Rapidia) showing an aneurysm in the distal M4 segment located 18.9 mm from the cortical surface.

Fig. 4

A fusiform aneurysm was visualized without cortex injury (A). The proximal part of aneurysm was clipped with a Yasagil clip (B).

Fig. 5

Cerebral angiogram performed 14 days after the operation shows the absence of an M4 aneurysm (A) and superficial temporal artery-middle cerebral artery anastomosis, which had good vascular integrity (B).