title: Loss of visual evoked potential following temporary occlusion of the superior hypophyseal artery during aneurysm clip placement surgery. Case report.
abstract: The authors report a case in which a 62-year-old woman with a history of subarachnoid hemorrhage due to a ruptured aneurysm was found to have a de novo paraclinoid aneurysm in the right internal carotid artery during a routine medical examination. Surgical clip placement was performed via a contralateral pterional approach under visual evoked potential (VEP) monitoring. The superior hypophyseal artery (SHA) was found to originate from the aneurysm body. The artery was temporarily occluded prior to application of the clip to the aneurysm neck. The VEP signal was lost 3 minutes after the SHA was occluded, and the potentials gradually recovered 10 minutes after the artery was released. The disappearance of VEP signal was reproducible with SHA occlusion. The clip was applied to the aneurysm body to preserve the origin of the SHA. The patient did not have any deterioration of vision after surgery. Intraoperative VEP monitoring can be used to help determine whether the SHA can be sacrificed safely.
authors.affiliation: Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Goto
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Kodama
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kusano
authors.forename: Keiichi
authors.initials: K
authors.lastname: Sakai
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hongo
mesh_terms: D017542:Aneurysm, Ruptured / Q000473:pathology / Q000601:surgery*; D015901:Angiography, Digital Subtraction; D002340:Carotid Artery Diseases / Q000473:pathology / Q000601:surgery; D002343:Carotid Artery, Internal / Q000473:pathology / Q000601:surgery; D002941:Circle of Willis; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology / Q000601:surgery*; D007431:Intraoperative Complications; D018810:Magnetic Resonance Angiography; D008875:Middle Aged; D010902:Pituitary Gland / Q000098:blood supply*; D013345:Subarachnoid Hemorrhage / Q000473:pathology / Q000601:surgery*; D013525:Surgical Instruments