(Kiosk 3) Syndrome of the Trephined in a Third-trimester Pregnancy

Case Diagnosis: 40 year old pregnant female who suffered a motor vehicle collision (MVC) and ultimately underwent craniectomy, who subsequently developed Syndrome of the Trephined.

Case Description or Program Description: 40 year old 2nd trimester pregnant female suffered a motor vehicle collision (MVC) which resulted in polytrauma including subdural hematoma (SDH) and subarachnoid hemorrhage (SAH). She underwent decompressive left hemicraniectomy and was discharged after an otherwise uncomplicated stay. At TBI clinic 3.5 months later, she noted that for a month she had severe headaches, double vision, episodes of slurred speech and right foot drag. On exam she had a sunken-appearing hemicraniectomy defect as well as word-finding difficulties, distal right upper extremity weakness and fine motor dysfunction. This was felt to be consistent with Syndrome of the Trephined.

Setting: Acute Care Hospital

Assessment/Results: Due to patient’s third-trimester pregnancy, sedation and cranioplasty were felt to be very high-risk and deferred. She delivered 2 weeks later, and 1 month later she underwent cranioplasty with symptom resolution.

Discussion (relevance): Syndrome of the Trephined, also known as “sinking flap syndrome,” is an uncommon and poorly understood complication after craniectomy. It is more common in patients with large defects and may be associated with leptomeningeal hemorrhagic lesions. It may potentially arise due to a change in intracranial fluid movement including both cerebrospinal fluid circulation and blood flow. It often presents with headaches, dizziness, fatigue, pain, and weakness. Average time of onset ranges between 1 month and 1 year. Early cranioplasty is associated with improved recovery, and delay with worse outcome. Little improvement has been noted after 4.5 months. However, risks of early surgery must be balanced with functional goals. In this case her third-trimester pregnancy was felt to be too high of a risk to proceed with surgery.

Conclusions: Patients with large craniectomies and leptomeningeal compartment lesions are at high risk of developing Syndrome of the Trephined. Cranioplasty typically yields resolution of these symptoms and functional improvements, but safety and timing of the surgery must be considered.