Superficial Temporal Artery-middle Cerebral Artery Anastomosis for Ischemic Stroke due to Dissection of the Intracranial Internal Carotid Artery with Middle Cerebral Artery Extension

Abstract

A 31-year-old man presented with a sudden-onset headache, right hemiparesis, and dysarthria on day 0 and was diagnosed with acute ischemic stroke due to dissection of the left intracranial internal carotid artery with middle cerebral artery extension. His symptoms progressed despite the institution of treatment, suggesting progression of the dissection. On day 5 after symptom onset, the patient underwent superficial temporal artery-middle cerebral artery anastomosis. No new ischemic stroke event occurred after surgery. Cerebral angiography performed 6 months after surgery showed spontaneous resolution of the dissection. The patient recovered to a modified Rankin Scale score of 2 and was able to return to work. The results of the present case suggest that superficial temporal artery-middle cerebral artery anastomosis is an effective treatment for ischemic stroke due to dissection of the intracranial internal carotid artery with middle cerebral artery extension.

Keywords: STA MCA bypass; internal carotid artery dissection; ischemic stroke; middle cerebral artery dissection.

Fig. 1

(A) Initial CT 2 days after onset of symptoms showing infarctions in the region of the left caudate, and lenticular nucleus, insular cortex, anterior and superior middle cerebral artery (MCA) territory. (B) Diffusion-weighted MRI 3 days after onset of symptoms showing hyperintense lesions in the left MCA area and left basal ganglia. (C) T2*-weighted MRI on day 3 revealing bleeding demonstrated by an area of low signal intensity (arrow) in the region of infarction in the frontal lobe. (D) Repeat CT on day 4 not showing expansion of area of infarction.

Fig. 2

(A) Three-dimensional computed tomography-angiography (3D-CTA) on day 3 showing the terminal portion of the left internal carotid artery and a superior branch of the left MCA demonstrate slight-to-moderate stenosis compared to its right-sided counterpart (arrow). (B) Magnetic resonance angiogram (MRA) obtained 3 h after the 3D-CTA on day 3, revealing string sign with extension from the distal supraclinoid segment of the left internal carotid artery to the horizontal segment of the MCA (arrow) without obvious aneurysmal dilatation.

Fig. 3

MRI images obtained 3 h after the 3D-CTA on day 3. (A) T1WI MRI showing high signal crescent sign (arrow) within the wall of the vessel. (B) T2WI MRI showing a vascular cavity (arrow). (C) The outer diameter of the left MCA is seen to have decreased on T2*-weighted imaging due to the presence of a suspected thrombus within the left MCA (arrow). (D) Constructive Interference in Steady State (CISS) MRI showing a vascular cavity (arrow). (E) Time of flight (TOF) MRI showing dilatation of the pseudolumen in the supraclinoid portion of the left internal carotid artery and horizontal portion of the left MCA (arrow). (F) MRA revealing a string sign in the left MCA (arrow).

Fig. 4

(A, B) Postoperative 3D-CTA on day 10 (A) and MRA on day 18 (B) revealing clear string and pearl sign in the left M1 portion (arrow). The superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is seen to be patent. (C) Follow up MRA 16 months later showing recanalization of the MCA (arrow) and flow reduction through the STA-MCA anastomosis.

Fig. 5

Follow up angiogram 6 months later. (A) Left internal carotid angiogram showing recanalization of the MCA. (B) Left external carotid angiogram showing good flow through the STA-MCA anastomosis.