Clinical and Radiological Predictors of Malignant Middle Cerebral Artery Infarction Development and Outcomes

Background Optic nerve sheath diameter (ONSD) can predict intracranial hypertension and outcomes in severe traumatic brain injury. Its utility in middle cerebral artery (MCA) stroke is unknown. Aims We reviewed serial radiological measurements, including ONSD, in patients with MCA stroke undergoing decompressive craniectomy (DC) for malignant MCA syndrome and compared demographic, clinical, and radiological data with an age- and gender-matched group of nonmalignant MCA stroke patients. Methods Patients admitted to a large tertiary hospital in London, UK, between April 2012 and October 2016 with MCA infarction were identified through 2 data sources. We quantified ONSD, eyeball transverse diameter (ETD), ONSD/ETD ratio, midline shift (MLS), and infarct volume on computed tomography (CT). Results We identified 19 patients (mean age = 49.8 years [standard deviation = 12.5]) with malignant MCA stroke and 19 patients (47.8 years [16.0]) with nonmalignant MCA stroke. Mean ONSD, ONSD/ETD ratio, MLS, and infarct volume on initial CT all significantly increased after developing malignant MCA syndrome and decreased (except infarct volume, which increased) following DC (all P s P  = .001; mean ONSD/ETD ratio: .25 [.03] versus .22 [.02], P  = .002). Conclusions ONSD, ONSD/ETD ratio, MLS, and infarct volume change dynamically in patients with malignant MCA infarction who undergo DC. An ONSD of more than 5.25 mm and an ONSD/ETD ratio of more than .232 on initial CT may identify MCA stroke patients at high risk of developing malignant MCA syndrome.