Introduction: We report a case of a Kernohan notch phenomenon caused by an acute life-threatening intracranial subdural hematoma due to a cerebrospinal fluid (CSF) leak following lumbar surgery. Case report: A 71-year-old patient underwent decompressive lumbar surgery for refractory neurogenic claudication. Intraoperatively. a dural tear was noted and repaired. https://www.getpureroutine.com/