title: Delayed presentation of an arteriovenous malformation after cerebellar hemangioblastoma resection-Case report.
abstract: BACKGROUND
  Haemangioblastoma has been uncommonly reported to occur in coexistence either temporally or spatially with the development of an arteriovenous malformations (AVM). We present a case of a delayed AVM following haemangioblastoma resection.
  
  
  METHODS
  44 year old female initially presented with a several week history of headaches, vertigo and nausea and emesis and was found to have a cystic lesion with a solid enhancing component on Magnetic Resonance Imaging (MRI) in the superior aspect of the vermis. She underwent gross total resection and final pathology was consistent with WHO grade I haemangioblastoma. One year later, patient re-presented with headaches, dizziness and left trochlear nerve palsy with rotary nystagmus. Imaging revealed a left posterior tentorial paramedian cerebellar vascular nidus with venous drainage into the left transverses sinus suspicious for arteriovenous malformation. She underwent gross total resection of the lesion. Final pathology confirmed the diagnosis of an arteriovenous malformation.
  
  
  CONCLUSIONS
  Recent research supports both haemangioblastoma and AVM are of embryologic origin but require later genetic alterations to develop into symptomatic lesions. It is unclear in our case if the AVM was present at the time of the initial haemangioblastoma resection or developed de novo after tumor resection. However, given the short time between tumor resection and presentation of AVM, de novo AVM although possible, appears less likely.
  
  
  CONCLUSIONS
  AVM and haemangioblastoma rarely presents together either temporally or spatially. We present a case of a delayed AVM following haemangioblastoma resection. More research is needed to elucidate the rare intermixture of these lesions.
authors.affiliation: Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: E Emily
authors.initials: EE
authors.lastname: Bennett
authors.affiliation: Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Balint
authors.initials: B
authors.lastname: Otvos
authors.affiliation: Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Varun R
authors.initials: VR
authors.lastname: Kshettry
authors.affiliation: Department of Neurological Surgery, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address: gonzalj1@ccf.org.
authors.forename: Jorge
authors.initials: J
authors.lastname: Gonzalez-Martinez
keywords: Arteriovenous malformation; Hemangioblastoma; von-Hippel-Lindau