title: Spontaneous delayed brain herniation through a subdural membrane after tumor surgery.
abstract: BACKGROUND
  We report on a rare case of spontaneous cerebral herniation through a subdural membrane in a 54-year-old patient. Brain herniation in adults as a complication of chronic subdural hematomas shortly after a neurosurgical intervention is rare. We are the first to report a case of delayed local herniation in an adult patient more than 1 year after a neurosurgical procedure.
  
  
  METHODS
  The patient suffered from a low-grade oligodendroglioma since 1993. Radiotherapy was then applied, followed by resective surgery and chemotherapy in 2008 because of tumor progression. Subsequently, he developed a symptomatic subdural hygroma treated with a subduro-atrial cerebrospinal fluid shunt. In January 2010, the shunt was occluded. Follow-up brain imaging showed a stable situation after tumor resection, with a cyst in the temporal resection cavity and a stable subdural hygroma. In February 2011, the patient visited the emergency department because of an acute right hemiparesis and progressive motor aphasia. Urgent magnetic resonance imaging was suspicious of a herniation of brain parenchyma in the left middle cranial fossa. Explorative surgery showed a locally incarcerated brain herniation through a membrane with a ring-like aperture. Resection of this membrane led to normalization of the position of the brain tissue and to clinical improvement.
  
  
  CONCLUSIONS
  Brain herniation through a subdural membrane is an extremely rare complication, but must be a differential diagnosis in patients with a known chronic subdural hematoma or hygroma and clinical deterioration, even in the absence of recent surgery. Urgent surgical intervention of the herniated brain is recommended to reduce the risk of permanent neurological damage.
authors.affiliation: Department of Neurology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Annelies
authors.initials: A
authors.lastname: Van Dycke
authors.affiliation: Department of Neurosurgery, Ghent University Hospital, Ghent, Belgium.
authors.forename: Jean-Pierre Kalala
authors.initials: JP
authors.lastname: Okito
authors.affiliation: Department of Radiology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Marjan
authors.initials: M
authors.lastname: Acou
authors.affiliation: Department of Radiology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: Deblaere
authors.affiliation: Department of Neurology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Hemelsoet
authors.affiliation: Department of Neurosurgery, Ghent University Hospital, Ghent, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Van Roost
mesh_terms: D001037:Aphasia / Q000209:etiology; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology / Q000601:surgery*; D003399:Craniotomy; D004677:Encephalocele / Q000209:etiology* / Q000473:pathology / Q000601:surgery*; D020200:Hematoma, Subdural, Chronic / Q000150:complications / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology / Q000534:rehabilitation; D019635:Neurosurgical Procedures / Q000379:methods; D049268:Positron-Emission Tomography; D011183:Postoperative Complications / Q000473:pathology* / Q000601:surgery*; D012640:Seizures / Q000209:etiology; D013355:Subdural Space / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome