Interictal and postictal language testing accurately lateralizes language dominant temporal lobe complex partial seizures.
OBJECTIVE
Noninvasive tests that accurately localize seizure onset provide great value in the presurgical evaluation of patients with intractable epilepsy. This study examined the diagnostic utility of three expressive language disturbances in lateralizing language-dominant (DOM) temporal lobe complex partial seizures: (1) the postictal language delay (PILD; time taken to correctly read a test phrase out loud immediately following seizures); (2) the production of postictal phonemic paraphasic errors (PostPE); and (3) interictal phonemic paraphasic errors (InterPE).


METHODS
All 60 subjects underwent inpatient video/EEG monitoring and had surgically confirmed temporal lobe epilepsy (TLE). We determined the presence and number of PostPE and, PILD times (in s) for 212 seizures, and InterPE on the Boston Naming Test (BNT). Each technique's diagnostic usefulness was evaluated via logistic regression and ROC curve analysis. Sensitivity, specificity, positive predictive value and negative predictive values were computed.


RESULTS
PILD, PostPE and InterPE production were equally effective and accurate in lateralizing DOM seizure onset. Patients with DOM TLE had a longer PILD and committed more PostPE and InterPE than those with nondominant (NDOM) TLE. Respective sensitivity and specificity values were as follows: PILD (84%, 86%), PostPE (94%, 64%), and InterPE (97%, 86%). No single predictor was significantly better but a combination model yielded enough incremental utility to collectively outperform each separate predictor model.


CONCLUSIONS
Interictal language testing is as accurate as postictal language testing in predicting DOM lateralization of TLE. Clinicians should also attend to the quality of errors produced during interictal and postictal language testing.
Ramirez
Maya J
MJ
Department of Psychology, University of Cincinnati, Cincinnati, Ohio 45221-0376, USA.
Schefft
Bruce K
BK
Howe
Steven R
SR
Hwa-Shain
Yeh
Y
Privitera
Michael D
MD
D000654:Amobarbital / Q000494:pharmacology; D038481:Anterior Temporal Lobectomy; D004569:Electroencephalography / Q000706:statistics & numerical data; D017029:Epilepsy, Complex Partial / Q000175:diagnosis* / Q000601:surgery; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000601:surgery; D007839:Functional Laterality / Q000187:drug effects / Q000502:physiology*; D006760:Hospitalization; D006801:Humans; D007802:Language; D007807:Language Tests / Q000706:statistics & numerical data*; D016015:Logistic Models; D008991:Monitoring, Physiologic; D009483:Neuropsychological Tests; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014743:Videotape Recording
D000654:Amobarbital