Hyperattenuations on flat-panel computed tomography after successful recanalization of mechanical thrombectomy for anterior circulation occlusion

Abstract

Background: To evaluate intraparenchymal hyperattenuation (IPH) on flat-panel computed tomography (FPCT) findings and their clinical usefulness for predicting prognosis after successful mechanical thrombectomy (MT) for acute occlusion of anterior circulation.Methods: A retrospective review was conducted for 158 consecutive patients undergoing mechanical thrombectomy during the last six years. After excluding those with posterior circulation occlusion or incomplete recanalization and those without FPCT, 82 patients were finally included. Immediate postprocedural IPH on FPCT was categorized into four patterns (none, striatal, cortical, or combined pattern).Follow-up magnetic resonance images or CT scans after 48 hours from MT were analyzed according to FPCT findings. The existence of hemorrhagic transformation, intracerebral hemorrhage, and brain swelling was evaluated. Functional clinical outcomes were accessed with post-procedural 3-month modified Rankin scales (mRS). Results: Of 82 patients, 34 patients were found to have IPH (16 with a striatal pattern, 8 with a cortical pattern, and 10 with a combined pattern). Hemorrhagic complication (P<0.001), brain swelling (P<0.001), and poor mRS scores (P=0.042) showed significant differences according to IPH patterns. Multivariate logistic regression analysis revealed that the presence of a striatal pattern (OR: 13.26, P<0.001), cortical pattern (OR: 11.61, P=0.009), and combined pattern (OR: 45.34, P<0.001) independently predicted hemorrhagic complications. The location of the occlusion (OR: 4.13, P=0.034), cortical pattern (OR: 5.94, P=0.039), and combined pattern (OR: 39.85, P=0.001) predicted brain swelling. Age (OR: 1.07, P=0.006) and the presence of a combined pattern (OR: 10.58, P=0.046) predicted poor clinical outcomes.Conclusions: FPCT is a rapid and effective tool for a prompt follow-up just after MT to predict prognosis. Those with striatal patterns showed relatively good clinical outcomes despite significant hemorrhage. Cortical IPH patterns independently predicted a high rate of post-procedural hemorrhage or brain swelling. Combined pattern is a strong predictor for both radiologic and poor clinical outcomes.

Role of Brain Imaging in the Prediction of Intracerebral Hemorrhage Following Endovascular Therapy for Acute Stroke

“…Several studies have reported that hyperdense areas are independently associated with both purely radiological and symptomatic post-EVT ICH. 61,62,67 Larger hyperdense areas are associated with higher risks of ICH. Further studies using dual-energy CT may help to decipher what these hyperdensities represent.…”

“…Following EVT, a focal hyperdense area is commonly observed on CT either acquired in the angiosuite using flat-panel CT or using standard CT immediately following EVT (Figure 2). 61,62,67 Such hyperdense areas may be a sign of iodine contrast leakage, bleeding, or a combination of both and more generally reflect BBB damage. Several studies have reported that hyperdense areas are independently associated with both purely radiological and symptomatic post-EVT ICH.…”

Cross-circulation thrombectomy for acute middle cerebral artery occlusion through a posterior communicating artery: a case report

“…The efficacy of endovascular treatments for acute ischemic stroke has been substantiated by several recent randomized clinical trials, and endovascular intervention received the strongest level I recommendation in recent American Heart Association/American Stroke Association guidelines ( 1 , 2 ). However, complex vascular anatomy and chronic lesions involving extracranial or intracranial vessels may make classical anterograde approaches through parent vessels challenging.…”

“…It helped save time, enhance the efficiency, and improve the clinical prognosis of the patient. However, cross-circulation approaches are also associated with potential risks, such as long procedure times (puncture to recanalization), hemorrhagic complications, and thromboembolic events in unaffected arterial territories ( 2 - 5 ). We report a clinical case of acute ischemic stroke in two simultaneous circulation systems due to the occlusion of intracranial arteries that was resolved by a cross-circulation mechanical thrombectomy procedure.…”