title: Navigation-assisted trans-inferotemporal cortex selective amygdalohippocampectomy for mesial temporal lobe epilepsy; preserving the temporal stem.
abstract: OBJECTIVE
  Selective amygdalohippocampectomy (SAH) can be used to obtain satisfactory seizure control in patients with mesial temporal lobe epilepsy (MTLE). Several SAH procedures have been reported to achieve satisfactory outcomes for seizure control, but none yield fully satisfactory outcomes for memory function. We hypothesized that preserving the temporal stem might play an important role. To preserve the temporal stem, we developed a minimally invasive surgical procedure, 'neuronavigation-assisted trans-inferotemporal cortex SAH' (TITC-SAH).
  
  
  METHODS
  TITC-SAH was performed in 23 patients with MTLE (MTLE on the language-non-dominant hemisphere, n = 11). The inferior horn of the lateral ventricle was approached via the inferior or middle temporal gyrus along the inferior temporal sulcus under neuronavigation guidance. The hippocampus was dissected in a subpial manner and resected en bloc together with the parahippocampal gyrus. Seizure control at one year and memory function at 6 months postoperatively were evaluated.
  
  
  RESULTS
  One year after TITC-SAH, 20 of the 23 patients were seizure-free (ILAE class 1), 2 were class 2, and 1 was class 3. Verbal memory improved significantly in 13 patients with a diagnosis of hippocampal sclerosis, for whom WMS-R scores were available both pre- and post-operatively. Improvements were seen regardless of whether the SAH was on the language-dominant or non-dominant hemisphere. No major complication was observed.
  
  
  CONCLUSIONS
  Navigation-assisted TITC-SAH performed for MTLE offers a simple, minimally invasive procedure that appears to yield excellent outcomes in terms of seizure control and preservation of memory function, because this procedure does not damage the temporal stem. TITC-SAH should be one of the feasible surgical procedures for MTLE.
  
  
  BACKGROUND
  SAH: Amygdalohippocampectomy; MTLE: Mesial temporal lobe epilepsy (MTLE); TITC-SAH: Ttrans-inferotemporal cortex SAH; ILAE: International League Against Epilepsy (ILAE); MRI: Magnetic resonance imaging; EEG: Electroencephalography (EEG); FDG-PET:8F-fluorodeoxyglucose (FDG)-positron emission tomography; ECoG: Electrocorticography; MEG: Magnetoencephalography; IMZ-SPECT: N-isopropyl-p(123I)-iodoamphetamine single photon emission computed tomography; WMS-R: Wechsler Memory Scale-Revised.
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Kishima
authors.affiliation: c Department of Neurosurgery , Kinki University School of Medicine , Osaka-sayama , Japan.
authors.forename: Amami
authors.initials: A
authors.lastname: Kato
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Oshino
authors.affiliation: b Epilepsy Center , Osaka University Hospital , Suita , Japan.|d Department of Neurosurgery , Osaka General Medical Center , Osaka , Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Tani
authors.affiliation: b Epilepsy Center , Osaka University Hospital , Suita , Japan.|e Department of Neurosurgery , Otemae Hospital , Osaka-sayama , Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Maruo
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Hui Ming
authors.initials: HM
authors.lastname: Khoo
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.|f Global Center for Medical Engineering and Informatics Division of Clinical Neuroengineering , Osaka University , Osaka , Japan.
authors.forename: Takufumi
authors.initials: T
authors.lastname: Yanagisawa
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Edakawa
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Hosomi
authors.affiliation: a Department of Neurosurgery , Osaka University Graduate School of Medicine , Suita, Osaka , Japan.|b Epilepsy Center , Osaka University Hospital , Suita , Japan.|f Global Center for Medical Engineering and Informatics Division of Clinical Neuroengineering , Osaka University , Osaka , Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hirata
authors.affiliation: f Global Center for Medical Engineering and Informatics Division of Clinical Neuroengineering , Osaka University , Osaka , Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yoshimine
mesh_terms: D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000000981:diagnostic imaging / Q000601:surgery*; D004833:Epilepsy, Temporal Lobe / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000209:etiology / Q000601:surgery*; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D009413:Nerve Fibers, Myelinated; D038361:Neuronavigation / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D017063:Outcome Assessment, Health Care; D055815:Young Adult
keywords: Mesial temporal lobe epilepsy; memory outcomes; minimally invasive; navigation-assisted trans-inferotemporal cortex-selective amygdalohippocampectomy; temporal stem