Patients with temporoparietal ictal symptoms and inferomesial EEG do not benefit from anterior temporal resection.
OBJECTIVE
The role of posterior structural lesions leading to inadequate results after inferomesial temporal resection is well recognized. Here we present poor surgical outcome in six patients with nonlesional intractable epilepsy, well-defined focal anterior and inferomesial temporal epileptic discharges, and posterior temporoparietal symptoms.


METHODS
We reviewed patient data including scalp video-EEG telemetry, intracranial EEG recording, magnetic resonance imaging (MRI) sequences (1.5 Tesla), and single-photon emission computed tomography (SPECT) findings.


RESULTS
Ictal onset was uni- or bilateral diffuse with late preponderance over one temporal, or centrotemporoparietal regions. Four patients had preresection intracranial EEG monitoring, which suggested an epileptogenic zone in the posterior temporal and inferior parietal area in two, in the temporal lobe in one, and was inconclusive in the remaining one, who showed late epileptiform activity in the temporal neocortex. A second intracranial implantation was performed in three of them after a first anterior temporal resection. This led to posterior temporal neocortical localization in two and posterior temporal-inferior parietal localization in one. Including subpial transection, these six patients had one to four operations each, but only limited improvement occurred as a result of surgery in this group of individuals.


CONCLUSIONS
We conclude that anterior and inferomesial interictal epileptiform temporal discharges and at times even intracranial EEG monitoring may be misleading. Anteromesial temporal resection is ineffective in patients with posterior temporoparietal clinical ictal features.
Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, Montreal, Quebec, Canada.
Yahya
Y
Aghakhani
Anna
A
Rosati
François
F
Dubeau
André
A
Olivier
Frederick
F
Andermann
D000328:Adult; D004569:Electroencephalography; D004827:Epilepsy / Q000175:diagnosis / Q000378:metabolism / Q000601:surgery; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D010296:Parietal Lobe / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D011182:Postoperative Care; D012189:Retrospective Studies; D013686:Telemetry / Q000295:instrumentation; D013702:Temporal Lobe / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D015899:Tomography, Emission-Computed, Single-Photon; D017211:Treatment Failure