title: Microsurgical retrieval of an endovascular microcatheter trapped during Onyx embolization of a cerebral arteriovenous malformation.
abstract: OBJECTIVE
  Cerebral arteriovenous malformations (AVMs) are vascular lesions that are amenable to various treatment modalities including stereotactic radiosurgery, fractionated radiotherapy, endovascular embolization, microsurgical obliteration or combined modality treatment. A potential complication of endovascular therapy with embolization material is microcatheter entrapment. We report on a patient for whom surgery was combined with endovascular embolization to obliterate an AVM and retrieve an entrapped endovascular microcatheter.
  
  
  METHODS
  A 52-year-old woman suffered a left parietal hemorrhage from an AVM. She underwent staged endovascular embolization of the lesion using Onyx material. During the second stage of the embolization, the microcatheter (Marathon Flow Directed Microcatheter; eV3 Neurovascular, Inc., Irvine, CA, USA) was retained in the Onyx plug. It was decided to section the microcatheter at the groin and proceed with microsurgical obliteration of the AVM, with removal of the entrapped microcatheter remnant.
  
  
  METHODS
  The AVM was dissected circumferentially allowing the meticulous obliteration of the feeding vessels. A single remaining feeding vessel originating from the distal anterior cerebral artery was identified and suspected to contain the entrapped microcatheter. The location was confirmed using stereotactic guidance (BrainLab, Munich, Germany) and the vessel was then sectioned allowing complete removal of the AVM. The microcatheter (102 cm) was then extracted cranially using gentle traction.
  
  
  CONCLUSIONS
  This demonstrates the first incidence of microcatheter removal after procedural entrapment in Onyx embolization material.
authors: Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. walcott.brian@mgh.harvard.edu
authors: Brian P
authors: BP
authors: Walcott
authors: Jason L
authors: JL
authors: Gerrard
authors: Raul G
authors: RG
authors: Nogueira
authors: Brian V
authors: BV
authors: Nahed
authors: Anna R
authors: AR
authors: Terry
authors: Christopher S
authors: CS
authors: Ogilvy
mesh_terms: D002404:Catheterization / Q000009:adverse effects*; D002543:Cerebral Hemorrhage / Q000601:surgery / Q000628:therapy*; D004121:Dimethyl Sulfoxide / Q000627:therapeutic use*; D004621:Embolization, Therapeutic / Q000009:adverse effects*; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery / Q000628:therapy*; D008866:Microsurgery / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D010296:Parietal Lobe / Q000098:blood supply; D011145:Polyvinyls / Q000627:therapeutic use*; D016634:Radiosurgery / Q000379:methods*
chemical_list: C450660:Onyx copolymer; D011145:Polyvinyls; D004121:Dimethyl Sulfoxide