Interictal and Postictal Language Testing Accurately Lateralizes Language Dominant Temporal Lobe Complex Partial Seizures

Abstract

SUMMARYPurpose: 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. KEY WORDS: Paraphasic error, postictal language delay, Epilepsy, Confrontation naming, Confrontation naming, Postictal language testing.Noninvasive methods that can localize or lateralize the epileptogenic focus are preferred in the evaluation of epilepsy surgery candidates. Prior studies have shown that postictal and interictal language disturbances can accu-

The effects of left or right hemispheric epilepsy on language networks investigated with semantic decision fMRI task and independent component analysis

“…Epilepsy directly and indirectly impacts language functions; the immediate effects of seizure(s) can be seen as an ictal or early post-ictal language dysfunction (30–32) while long term language dysfunction is noted on detailed neuropsychological evaluation (61). In general, seizures originating from the dominant hemisphere usually are associated either with a speech arrest during the seizure or paraphasic errors after the seizure.…”

“…In general, seizures originating from the dominant hemisphere usually are associated either with a speech arrest during the seizure or paraphasic errors after the seizure. Clinically, such information is frequently used as a diagnostic tool to determine the localization and lateralization of language dominance and, in certain cases, this information may be helpful in localizing the epileptic focus (32, 61–63). While clinical testing during or after ictus has high predictive value for determining language dominance, cognitive assessments are less likely to provide detailed anatomical information regarding language center(s) location, especially in patients with preexisting anatomical of functional abnormalities as seen in epilepsy (64, 65).…”

Hyperactivation of parahippocampal region and fusiform gyrus associated with successful encoding in medial temporal lobe epilepsy

“…Handedness was studied with a standard Oldfield test (Oldfield, 1971), confirming that all subjects included were right‐handed. Interictal and postictal language testing was in addition performed in all patients to evaluate hemispheric dominance for language, as proposed previously (Privitera et al., 1991; Ramirez et al., 2008; Privitera & Kim, 2010). Six patients with questionable findings (Patients 1, 2, 4, 5, 6, and 10; Table 1) were secondarily evaluated with fMRI (Powell & Duncan, 2005; Trebuchon‐Da Fonseca et al., 2009), confirming left hemispheric language dominance.…”

Preoperative language lateralization in temporal lobe epilepsy (TLE) predicts peri-ictal, pre- and post-operative language performance: An fMRI study

“…In LTLE, ictal and postictal language impairments (peri-ictal aphasia) occur in 75–82% of LTLE patients (Gabr et al, 1989; Koerner and Laxer, 1988) and are associated with left language dominance on the Wada test (Ramirez et al, 2008). LTLE patients without peri-ictal aphasia are therefore more likely to have atypical (i.e.…”