Typical and Atypical Perfusion Patterns in Periictal SPECT of Patients with Unilateral Temporal Lobe Epilepsy

• Published in: Epilepsia (Copenhagen) 2001-05, Vol.42 (5), p.660-666
• Main Authors: Wichert‐Ana, Lauro, Velasco, Tonicarlo Rodrigues, Terra‐Bustamante, Vera Cristina, Araújo, David, Júnior, Veriano Alexandre, Kato, Mery, Leite, João Pereira, Assirati, João Alberto, Machado, Hélio Rubens, Bastos, Alexandre Cunha, Sakamoto, Américo Ceiki
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Biological and medical sciences; Electroencephalography - statistics & numerical data; Epilepsy; Epilepsy, Temporal Lobe - diagnosis; Epilepsy, Temporal Lobe - diagnostic imaging; Epilepsy, Temporal Lobe - physiopathology; Female; Functional Laterality - physiology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Male; Medical sciences; Middle Aged; Monitoring, Physiologic - statistics & numerical data; Nervous system (semeiology, syndromes); Neurology; Perfusion patterns; rCBF; Retrospective Studies; SPECT; Surgery; Temporal Lobe - blood supply; Temporal Lobe - diagnostic imaging; Temporal Lobe - physiopathology; Temporal lobe epilepsy; Tomography, Emission-Computed, Single-Photon - statistics & numerical data; Videotape Recording
• ISSN: 0013-9580; 1528-1167
• DOI: 10.1046/j.1528-1157.2001.41900.x

Purpose: To characterize perfusion patterns of periictal single‐photon emission tomography (SPECT) in patients with unilateral temporal lobe epilepsy (TLE) and to determine their relationship to the epileptogenic zone (EZ). Methods: We studied periictal SPECT scans of 53 patients after anterior mesial temporal lobectomy who had good seizure outcome after surgery. Ictal SPECT scans were performed during video‐EEG monitoring. Typical SPECT patterns consisted of ipsilateral ictal hyperperfusion or ipsilateral postictal hypoperfusion. Atypical ictal patterns included normal scans, bilateral temporal hyperperfusion, or contralateral patterns. These perfusion patterns were retrospectively analyzed searching for concordance rate with the EZ. Results: We obtained 51 ictal and two early postictal scans. In the typical group, 40 (75.4%) patients had ipsilateral ictal temporal lobe hyperperfusion, and one (1.9%) patient had ipsilateral postictal temporal lobe hypoperfusion. Twelve (22.7%) patients exhibited atypical perfusion patterns: seven (13.2%) patients had bitemporal ictal hyperperfusion (four cases showed asymmetric temporal lobe changes), four (7.6%) patients had contralateral hyperperfusion, and one (1.9%) patient had a normal SPECT scan. All four patients with bitemporal asymmetric hyperperfusions showed greater perfusion lateralized to the side of the EZ. Three of the four patients who had contralateral hyperperfusion also had a complex postictal‐like pattern in the ipsilateral temporal lobe consisting of anteromesial hyperperfusion with adjacent lateral hypoperfusion. Conclusions: This study analyzed typical and atypical perfusion patterns in unilateral TLE, and suggested that not only typical, but also some atypical perfusion patterns may contribute to the lateralization of EZ.