title: Olfactory auras in patients with temporal lobe epilepsy.
abstract: OBJECTIVE
  To investigate olfactory auras in patients with temporal lobe epilepsy (TLE).
  
  
  METHODS
  We reviewed medical records of 217 Chinese patients who underwent temporal lobectomy for medically intractable TLE between 1987 and 1998 in Taiwan. Patients with olfactory auras asked for detailed characteristics of their auras.
  
  
  RESULTS
  In all, 12 (5.5%) patients had olfactory auras, seven men and five women. All patients except one described and characterized the unpleasant olfactory auras. Olfactory auras were usually combined with other auras, most frequently sensations of epigastric rising, nausea, and fear. Association with gustatory hallucination was uncommon, in only one patient. On neuroimaging study, 11 patients had structural lesions involving the mesial temporal structures, two exclusively involving the amygdala. Histologic diagnosis included gliosis of the mesial temporal regions in seven (58.3%) patients, neoplasm in four (33.3%) patients, and arteriovenous malformation in one patient. Postoperatively, eight patients were seizure free. Three patients had rare seizures; however, none reported residual olfactory auras.
  
  
  CONCLUSIONS
  Olfactory auras are infrequent in TLE. In this study, mesial temporal sclerosis is the most common etiology rather than tumors. Mesial temporal structures, especially the amygdala, may play important roles in the genesis of olfactory auras.
authors.affiliation: Department of Neurology, The Neurological Institute, Taipei Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chien
authors.initials: C
authors.lastname: Chen
authors.forename: Yang-Hsin
authors.initials: YH
authors.lastname: Shih
authors.forename: Der-Jen
authors.initials: DJ
authors.lastname: Yen
authors.forename: Jiing-Feng
authors.initials: JF
authors.lastname: Lirng
authors.forename: Yuh-Cherng
authors.initials: YC
authors.lastname: Guo
authors.forename: Hsiang-Yu
authors.initials: HY
authors.lastname: Yu
authors.forename: Chun-Hing
authors.initials: CH
authors.lastname: Yiu
mesh_terms: D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology; D001927:Brain Diseases / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D001932:Brain Neoplasms / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D004827:Epilepsy / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006212:Hallucinations / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012903:Smell / Q000502:physiology*; D013702:Temporal Lobe / Q000473:pathology / Q000503:physiopathology