title: Occurrence and therapy of space-occupying cystic lesions after brain tumor surgery.
abstract: OBJECTIVE
  Space-occupying cystic lesions may develop in a variable time after resection of particular intracranial tumors, representing a small amount of complications of these procedures. We present our experience with the development and operative treatment of such postoperative cystic lesions in order to identify possible risk factors and to optimize the treatment.
  
  
  METHODS
  The records and neuroradiological findings of patients, operated on either gliomas and meningeomas or craniopharyngeomas, who developed symptomatic cystic lesions in the former tumor resection area during the last ten years, were analyzed.
  
  
  RESULTS
  31 patients (2.5%) out of a total of 1240 corresponding tumor operations were identified. The mean age among the 20 female and 11 male patients was 47 years (12-74 years). In 17 patients (55%) the cystic lesion occured within 6 months after tumor resection (mean 5.6 weeks) and in 14 patients (45%) later than 6 months postoperatively (mean 3.6 years). 22 patients (71%) had malignant tumors and 16 patients (52%) had previous radiation therapy. 14 patients (45%) had more than one tumor resection at the same location and one patient had a postoperative meningitis as predisposing factor for the cyst-formation. All patients profited of the various definitive treatment modalities: repetitive percutaneous puncture/external drainage (5 patients), craniotomy for cyst-resection/-fenestration without (5 patients) and with Rickham-catheter implantation (10 patients), endoscopic cyst-fenestration with Rickham-catheter implantation (3 patients) and implantation of cysto-atrial or cysto-peritoneal shunts (8 patients).
  
  
  CONCLUSIONS
  Symptomatic cystic lesions developing after brain tumor resection may occur as early - (5.6 weeks) or as late - (3.6 years) complications and though predisposing factors, like malignant primary tumor, preceding radiation therapy and multiple tumor resections can be identified, the reason for their occurrence remains unclear. A variety of effective therapy options is applicable but should consider the patients condition and prognosis.
authors.affiliation: Department of Neurosurgery, University Hospital RWTH Aachen, Germany. Marcus.Korinth@post.rwth-aachen.de
authors.forename: M C
authors.initials: MC
authors.lastname: Korinth
authors.forename: M R
authors.initials: MR
authors.lastname: Weinzierl
authors.forename: T
authors.initials: T
authors.lastname: Krings
authors.forename: J M
authors.initials: JM
authors.lastname: Gilsbach
mesh_terms: D001254:Astrocytoma / Q000601:surgery; D001921:Brain / Q000601:surgery*; D001927:Brain Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000628:therapy; D003397:Craniopharyngioma / Q000601:surgery; D003399:Craniotomy; D003560:Cysts / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000628:therapy*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008577:Meningeal Neoplasms / Q000601:surgery; D008579:Meningioma / Q000601:surgery; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000628:therapy; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome