Perilesional Gliosis Is Associated with Outcome after Perinatal Stroke

Abstract

AbstractPerinatal ischemic stroke results in focal brain injury and life-long disability. Hemiplegic cerebral palsy and additional sequelae are common. With no prevention strategies, improving outcomes depends on understanding brain development. Reactive astrogliosis is a hallmark of brain injury that has been associated with outcomes but is unstudied in perinatal stroke. In this article, we hypothesized that gliosis was quantifiable and its extent would inversely correlate with clinical motor function. This was a population-based, retrospective, and cross-sectional study. Children with perinatal arterial ischemic stroke (AIS) or periventricular venous infarction (PVI) with magnetic resonance (MR) imaging were included. An image thresholding technique based on image intensity was utilized to quantify the degree of chronic gliosis on T2-weighted sequences. Gliosis scores were corrected for infarct volume and compared with the Assisting Hand and Melbourne Assessments (AHA and MA), neuropsychological profiles, and robotic measures. In total, 42 children were included: 25 with AIS and 17 with PVI (median = 14.0 years, range: 6.3–19 years, 63% males). Gliosis was quantifiable in all scans and scores were highly reliable. Gliosis scores as percentage of brain volume ranged from 0.3 to 3.2% and were comparable between stroke types. Higher gliosis scores were associated with better motor function for all three outcomes in the AIS group, but no association was observed for PVI. Gliosis can be objectively quantified in children with perinatal stroke. Associations with motor outcome in arterial but not venous strokes suggest differing glial responses may play a role in tissue remodeling and developmental plasticity following early focal brain injury.