Olfactory auras in patients with temporal lobe epilepsy.
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.
Chen
Chien
C
Department of Neurology, The Neurological Institute, Taipei Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei, Taiwan.
Shih
Yang-Hsin
YH
Yen
Der-Jen
DJ
Lirng
Jiing-Feng
JF
Guo
Yuh-Cherng
YC
Yu
Hsiang-Yu
HY
Yiu
Chun-Hing
CH
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