Olfactory Auras in Patients with Temporal Lobe Epilepsy

• Published in: Epilepsia (Copenhagen) 2003-02, Vol.44 (2), p.257-260
• Main Authors: Chen, Chien, Shih, Yang‐Hsin, Yen, Der‐Jen, Lirng, Jiing‐Feng, Guo, Yuh‐Cherng, Yu, Hsiang‐Yu, Yiu, Chun‐Hing
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Amygdala - pathology; Amygdala - physiopathology; Aura; Biological and medical sciences; Brain Diseases - complications; Brain Diseases - diagnosis; Brain Diseases - physiopathology; Brain Neoplasms - complications; Brain Neoplasms - diagnosis; Brain Neoplasms - physiopathology; Epilepsy - diagnosis; Epilepsy - etiology; Epilepsy - physiopathology; Epilepsy, Temporal Lobe - diagnosis; Epilepsy, Temporal Lobe - etiology; Epilepsy, Temporal Lobe - physiopathology; Female; Hallucinations - diagnosis; Hallucinations - etiology; Hallucinations - physiopathology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Nervous system (semeiology, syndromes); Neurology; Olfactory aura; Olfactory hallucination; Smell - physiology; Temporal Lobe - pathology; Temporal Lobe - physiopathology; Temporal lobe epilepsy; Temporal lobectomy; Tropical medicine
• ISSN: 0013-9580; 1528-1167
• DOI: 10.1046/j.1528-1157.2003.25902.x

Purpose: 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.