Prevalence of Visible Subdural Spaces in Benign Enlargement of Subarachnoid Spaces in Infancy: A Retrospective Analysis Utilizing Magnetic Resonance Imaging.

Abstract

Benign Enlargement of the Subarachnoid Spaces in Infancy (BESSI) is a common finding during workup for progressive macrocephaly. BESSI has been associated with slightly higher prevalence of subdural (SD) spaces and a risk for developing subdural hematoma. This study utilizes fast brain magnetic resonance imaging (MRI) to investigate the prevalence of visible SD spaces in BESSI. A retrospective review was performed for all pediatric patients who underwent brain MRI for macrocephaly. Patients with a diagnosis of BESSI were included in the study. A total of 109 patients met the inclusion criteria. Patient demographics were collected, and images were reviewed for size of subarachnoid, visible SD spaces, and ventricle size. Descriptive and inferential statistics were performed. The average age was 8 ± 4.6 months, 64 (59%) were male, and 55 patients had no previous medical history (50%). Sixty-seven percent of all patients were identified to have visible SD spaces. Eleven patients had confirmed SD hematomas; 1 patient was deemed to have abusive head trauma. Visible SD spaces were associated with younger age (6.9 months). Thirty-one patients with visible SD spaces had follow-up MRI, with complete resolution by 33 months. BESSI is a self-limiting pathology that has been associated with visible SD spaces and potential risk for SD hemorrhages. We report a high prevalence of visible SD spaces within BESSI through utilization of fast brain MRI. These spaces may contribute to the higher rate of incidental subdural hematoma in this population.