title: Symptomatic mass effect of a hypertrophied pericranial flap after repair of a dural defect: case report.
abstract: OBJECTIVE
  To detail a potential complication of the use of vascularized pericranial flaps in the repair of dural defects, namely, flap hypertrophy secondary to venous engorgement.
  
  
  METHODS
  A 23-year-old man with a left parietal lobe hemangiopericytoma underwent a craniotomy for tumor resection. The resultant dural defect was repaired with a vascularized pericranial flap. On postoperative Day 3, the patient developed headache, confusion, aphasia, and right upper extremity apraxia. Imaging revealed an extra-axial collection at the craniotomy site; on reexploration, a swollen, engorged pericranial flap causing mass effect was found.
  
  
  METHODS
  The pericranial flap was excised.
  
  
  CONCLUSIONS
  In this case, hypertrophy of the vascularized pericranial flap is hypothesized to have occurred because of venous congestion, possibly secondary to restriction of venous outflow by the overlying bone flap.
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Khoi D
authors.initials: KD
authors.lastname: Than
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Kretzer
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Dorsi
authors.forename: Jon D
authors.initials: JD
authors.lastname: Weingart
mesh_terms: D000328:Adult; D004388:Dura Mater / Q000293:injuries* / Q000473:pathology / Q000601:surgery*; D006083:Graft Occlusion, Vascular / Q000209:etiology* / Q000601:surgery*; D006801:Humans; D006984:Hypertrophy; D008297:Male; D012886:Skull / Q000098:blood supply / Q000637:transplantation*; D013524:Surgical Flaps / Q000009:adverse effects* / Q000473:pathology*; D016896:Treatment Outcome