Kirsten E Stoner1, Kingsley O Abode-Iyamah2, Nicole M Grosland1, Matthew A Howard3. 1. Department of Biomedical Engineering, University of Iowa, Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa, USA. 2. Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA. 3. Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA. Electronic address: matthew-howard@uiowa.edu.
Abstract
BACKGROUND: Decompressive craniectomy procedures are performed in patients with malignant intracranial hypertension. A bone flap is removed to relieve pressure. Later, a second operation is performed to reconstruct the skull after brain swelling has resolved. This surgical treatment would be improved if it were possible to perform a single operation that decompressed the brain acutely and eliminated the need for a second operation. To design a device and procedure that achieve this objective, it is essential to understand how the brain swells after a craniectomy procedure. METHODS: We identified 20 patients with ischemic stroke who underwent a decompressive hemicraniectomy operation. Skull defect morphology and postoperative brain swelling were measured using computed tomography scan data. Additional intracranial volume created by placing a hypothetical cranial plate implant offset from the skull surface by 5 mm was measured for each patient. RESULTS: The average craniectomy area and brain herniation volume was 9999 ± 1283 mm2 and 30.48 ± 23.56 mL, respectively. In all patients, the additional volume created by this hypothetical implant exceeded the volume of brain herniation observed. CONCLUSIONS: These findings show that a cranial plate with a 5-mm offset accommodates the brain swelling that occurs in this patient population. Copyright Â
BACKGROUND: Decompressive craniectomy procedures are performed in patients with malignant intracranial hypertension. A bone flap is removed to relieve pressure. Later, a second operation is performed to reconstruct the skull after brain swelling has resolved. This surgical treatment would be improved if it were possible to perform a single operation that decompressed the brain acutely and eliminated the need for a second operation. To design a device and procedure that achieve this objective, it is essential to understand how the brain swells after a craniectomy procedure. METHODS: We identified 20 patients with ischemic stroke who underwent a decompressive hemicraniectomy operation. Skull defect morphology and postoperative brain swelling were measured using computed tomography scan data. Additional intracranial volume created by placing a hypothetical cranial plate implant offset from the skull surface by 5 mm was measured for each patient. RESULTS: The average craniectomy area and brain herniation volume was 9999 ± 1283 mm2 and 30.48 ± 23.56 mL, respectively. In all patients, the additional volume created by this hypothetical implant exceeded the volume of brain herniation observed. CONCLUSIONS: These findings show that a cranial plate with a 5-mm offset accommodates the brain swelling that occurs in this patient population. Copyright Â