Cerebral Hyperperfusion Syndrome After a Burr Hole Drainage Surgery for Chronic Subdural Hematoma

Although chronic subdural hematoma (CSDH) has a good prognosis after classical minimally-invasive drainage surgery, severe complications still occur at a substantial rate. Cerebral hyperperfusion syndrome (CHS), which is a common severe complication after carotid endarterectomy or carotid artery stenting for cervical carotid artery stenosis, is rare after drainage surgery for a CSDH. We describe the case of an 82-year-old woman who presented with ipsilesional symptoms including contralateral hemiparesis and dysarthria, progressively worsening consciousness, and status epilepticus after a burr hole drainage surgery for CSDH. Magnetic resonance fluid-attenuated inversion recovery imaging showed diffuse subcortical low intensity in the ipsilesional hemisphere almost simultaneously with the appearance of the symptoms. Arterial spin labeling magnetic resonance perfusion imaging showed the abnormal increase of cerebral blood flow in the hemisphere. Continuous propofol administration and blood pressure management improved the symptoms. CHS can cause severe postoperative complications after drainage surgery for CSDH. Subcortical low-intensity fluid-attenuated inversion recovery imaging is a useful investigation for early detection of CHS in CSDH, and arterial spin labeling imaging is an effective minimally-invasive modality for confirming the diagnosis.