Role of Sulcal Hyperintensity and Web/Net Appearance on MRI in Patients With Chronic Subdural Hematoma Presenting With Transient Neurological Deficits

BACKGROUND AND OBJECTIVES: Transient neurological deficits (TNDs) in patients with chronic subdural hematoma (CSDH), such as fluctuating aphasia, hemiparesis, or sensory disturbances, present diagnostic and treatment challenges as their pathophysiology remains unclear. The aim of this study was to investigate the association between specific MRI findings and TNDs in patients with CSDH and explored their relationship through intraoperative observation. METHODS: We retrospectively evaluated 72 patients with CSDH who underwent preoperative MRI among 251 CSDH patients treated from January 2020 to December 2023. Sulcal hyperintensity (SHI) on fluid-attenuated inversion recovery images and web/net appearance (W/N) on T2*-weighted images were assessed and their association with TNDs was analyzed. Flexible neuroendoscopic surgery (FNS) was performed on 8 patients with TNDs exhibiting these MRI findings, allowing intraoperative observation of intrahematoma conditions. Histopathological examination was performed on hematoma samples. RESULTS: Thirteen patients (5.2%) presented with preoperative TNDs. Diffuse SHI and W/N were strongly associated with preoperative TNDs (odds ratio = 150.0, P < .001). FNS revealed organized hematomas with inflammatory changes corresponding to the SHI and W/N seen on MRI. Patients who underwent FNS experienced complete resolution of TNDs postprocedure, with diffuse SHI disappearing by one month. No recurrence was observed at a mean follow-up of 5.9 months. CONCLUSION: This study provided the first evidence that the combination of diffuse SHI and W/N on MRI strongly correlates with TNDs in patients with CSDH, serving as valuable diagnostic indicators. These findings will aid in guiding surgical approach selection and facilitate more personalized treatment strategies for patients with CSDH presenting with TNDs.