title: A Contralateral Transcondylar Fossa Approach with Bilateral V3 Segment Exposure for Repairing Complex Vertebral Artery Aneurysms.
abstract: BACKGROUND
  Microsurgical treatment for vertebral artery aneurysms can be approached through the lateral aspect of the brainstem and cerebellum. A contralateral approach may be selected in complex aneurysms with tortuous running and the intracranial vertebral artery distal to the aneurysm located in the contralateral cerebellopontine angle. When repairing the aneurysm, exposing the V3 segment before craniotomy is advantageous. We describe the detailed surgical procedures of the contralateral transcondylar fossa approach with bilateral V3 segment exposure for the repair of a complex vertebral artery aneurysm.
  
  
  METHODS
  A 48-year-old woman presented with a 23-mm unruptured thrombosed fusiform aneurysm in the right vertebral artery. The aneurysm and the V4 segment distal to it deviated to the left, and the aneurysm was compressing the left anterior aspect of the medulla oblongata. We treated the patient with trapping and thrombectomy, using a contralateral transcondylar fossa approach with bilateral V3 exposure. During the procedure, proximal vascular control was achieved by occluding the contralateral V3 segment and distal control was achieved by occluding the V4 segment. The aneurysm was successfully trapped and decompressed. The patient's postoperative course was good and she was discharged with a modified Rankin Scale score of 0.
  
  
  CONCLUSIONS
  The contralateral transcondylar fossa approach with bilateral V3 exposure is feasible for the repair of complex vertebral artery aneurysms showing a deviated and difficult to access V4 segment proximal to the aneurysm. Bilateral V3 exposure may also facilitate aneurysm bypass procedures such as those using a V3-V4 anastomosis.
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Nakao
authors.initials: N
authors.lastname: Ota
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan. Electronic address: taniroku@gmail.com.
authors.forename: Rokuya
authors.initials: R
authors.lastname: Tanikawa
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Miyama
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Miyazaki
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Kinoshita
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Matsukawa
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Sakakibara
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Saito
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Miyata
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Kosumo
authors.initials: K
authors.lastname: Noda
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Tsuboi
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Kamiyama
authors.affiliation: Stroke Center, Department of Neurosurgery, Sapporo Teishinkai Hospital, Higashi-ku, Sapporo, Hokkaido, Japan.
authors.forename: Sadahisa
authors.initials: S
authors.lastname: Tokuda
authors.affiliation: Department of Neurosurgery, Asahikawa Medical University, Asahikawa, Japan.
authors.forename: Kyousuke
authors.initials: K
authors.lastname: Kamada
mesh_terms: D002533:Cerebral Angiography; D000072226:Computed Tomography Angiography; D003399:Craniotomy; D004210:Dissection; D005260:Female; D056973:Four-Dimensional Computed Tomography; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D056888:Patient Positioning; D017131:Thrombectomy; D014656:Vascular Surgical Procedures / Q000379:methods*; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000601:surgery*
keywords: Bilateral V3 segment exposure; Complex vertebral artery; Contralateral approach; Transcondylar fossa approach