Prognostic value of the consistency of lateralizing ictal features and ictal EEG in patients undergoing temporal lobectomy for refractory complex partial seizures

Purpose: Ictal and postictal clinical manifestations have lateralizing value in the presurgical evaluation of intractable seizures. The consistency and frequency of these signs during seizures and the associated implications for postoperative seizure outcome are unknown. Methods: The videotaped complex partial seizures of 49 patients with known postoperative outcomes greater than 2 years after temporal lobectomy were blindly reviewed for: (1) unilateral hand posturing (UHP), (2) unilateral hand automatism (UHA), (3) forced and nonforced head turning (HT), and (4) postictal dysphasia (PID). The presence and laterality of each assessable sign were recorded. Data were analyzed as follows: (1) the prevalence of each sign in patients with Engel class 1 and Engel class 2-4, and (2) the postsurgical outcome when the sign was present in more than or less than 50% of the seizures for each patient. We reviewed patients' presurgical work-up, specifically ictal EEG and MRI. Results: The prevalence of UHP, UHA, HT, and PID was similar for Engel class 1 and Engel class 2-4 patients. Engel class 1 outcome when UHP UHA, HT, and PID were present for greater than 50% of seizures was no different compared to when these signs were present for less than 50% of seizures. Patients who had concordant ictal EEG and MRI abnormalities had the best postsurgical outcome. Conclusions: The consistency and frequency of ictal manifestations in the presurgical evaluation of complex partial seizures does not predict seizure outcome. The presence of any specific lateralizing sign need not be present in every complex partial seizure for the sign to hold predictive value. Concordant ictal EEG and MRI abnormalities are still the best predictors of outcome.