496: REVERSIBLE MALIGNANT CEREBRAL EDEMA FOLLOWING CRANIOPLASTY

Abstract

Introduction: Cranioplasty is a low-risk procedure and is performed for improving hydrocephalus and cerebral protection after decompressive craniectomy. Until recently, a complication that received little attention despite the devastating consequences is malignant cerebral swelling occurring after cranioplasty. There is limited knowledge regarding the pathophysiology or prevention of this condition. We present a novel case wherein a patient developed malignant cerebral swelling and fully recovered from the event. Description: 44-year-old female initially hospitalized in January 2021 for a right MCA occlusion; she received Alteplase and thrombectomy was performed. Hospital course was complicated by post procedure CT head showing midline shift and mass effect for which she was taken for right sided hemicraniectomy and right temporal lobectomy. She underwent tracheostomy, PEG and was discharged. She presented back in August 2021 for an elective right sided cranioplasty. The operative course was uneventful, a hemovac was placed with a subgaleal drain and a postoperative CT head showed cranioplasty in good position. That evening, the patient became increasingly lethargic, and was intubated. She was given hyperosmotic therapy and a repeat CT head showed newly evolving right PCA infarct, cerebellar infarcts with edema, worsening subdural hematoma and left MCA infarcts. While obtaining the repeat CT head, the patient developed seizures with progression to status epilepticus and was started on a midazolam infusion. CEEG showed epileptiform potentials in the right posterior quadrant and left hemisphere, without seizures. Two days later, on a repeat CT head there were no new findings. Patient began to improve clinically, and MRI brain on day 3 didn’t show new infarct or lesion other than encephalomalacia. She was transferred out of the ICU on day 6, a stability CT head three weeks later was stable, and she was discharged to acute rehab. Discussion: Transient malignant swelling followed cranioplasty is a high risk complication and possibly related to severe TBI, SSFS and vacuum suction drainage. Our patient is the first reported survivor from this. Further research and investigation of other cases should be identified to assess for commonalities and interventions to provide the best chance of recovery.