Microsurgical embolectomy with superficial temporal artery-middle cerebral artery bypass for acute internal carotid artery dissection: A technical case report

Abstract

Background: Dissection of the internal carotid artery (ICA) is an important cause of stroke. Intravenous alteplase administration and mechanical thrombectomy have been strongly recommended for selected patients with acute ischemic stroke. However, the efficacy and safety of these treatments for ischemic stroke due to ICA dissection remain unclear. Here, we report a case of acute ICA dissection successfully treated by microsurgical embolectomy.

Case description: A 40-year-old man presented with sudden left hemiparesis and in an unconscious state, with a National Institutes of Health Stroke Scale score of 14. Preoperative radiologic findings revealed an ICA dissection from the extracranial ICA to the intracranial ICA and occlusion at the superior-most aspect of the ICA. A dissection at the superior-most aspect of the ICA occlusion could not be confirmed; therefore, a surgical embolectomy with bypass was initiated. It became apparent that the superior ICA occlusion was not due to dissection but rather to an embolic occlusion; therefore, we undertook a surgical embolectomy and cervical ICA ligation with a double superficial temporal artery-middle cerebral artery bypass. The postoperative course was uneventful and, at the 6-month follow-up, the Modified Rankin Scale score for this patient was 1.

Conclusion: Surgical embolectomy with or without bypass can safely treat acute ischemic stroke due to an ICA dissection that cannot be distinguished between a dissecting occlusion and an embolic occlusion. Thus, it may be considered as an alternative option for patients in whom mechanical thrombectomy has failed or for those who are ineligible for mechanical thrombectomy.

Keywords: Acute ischemic stroke; Internal carotid artery dissection; Pathologic finding; Superficial temporal artery-middle cerebral artery bypass; Surgical embolectomy.

Figure 1:

Time-of-flight (TOF) magnetic resonance angiography at onset. (a) A double lumen sign is identified in the C7 segment of the internal carotid artery (ICA). (b) 3D TOF showed narrowing of the C7 portion of the ICA. The line represents the reference line of figure (a). (c) A double lumen sign is identified in the C3 segment of the ICA. (d) The line represents the reference line of figure (c).

Figure 2:

Diffusion-weighted image (DWI) and digital subtraction angiography. (a) DWI showed infarction of the posterior limb of the internal capsule, basal ganglia, and the insular and frontal cortices. (b and c) Digital subtraction angiography showed C7 narrowing and the superior-most aspect of the ICA occlusion.

Figure 3:

Treatment time course. Surgical embolectomy began 198 min after the patient was admitted to the emergency room. Superficial temporal artery-middle cerebral artery bypass was completed 2 h after skin incision (6.7 h after onset), and complete recanalization was established 8.3 h (498 min) after onset.

Figure 4:

Postoperative imaging. (a) computed tomography angiography showed good patency of the superficial temporal artery-middle cerebral artery bypass and recanalization at the superior-most aspect of the internal carotid artery. (b) Diffusion- weighted image showed no additional infarction. (c) T2 imaging 2 weeks postonset showed hyperintensity on the posterior limb of the internal capsule and basal ganglia.

Figure 5:

Pathological findings. Within the red thrombus, the internal elastic lamina is included in the Elastica-HE (a) and Elastica van Gieson stain (b). Calcification was also identified by Elastica van Gieson stain (c). CD34+ cells are identified in the thrombus (d).

Figure 6:

Thrombus characteristics. CD3+ (a), CD20+ (b), and CD 68+ (c) cells are infiltrated in the thrombus.