Factors Associated with Work Outcome After Anterior Temporal Lobectomy for Intractable Epilepsy

Summary: Purpose: Whereas the effect of anterior temporal lobectomy on seizure frequency is well recognized, less is known about its impact on work status.
Methods: One hundred thirty-four of 190 consecutive patients with temporal lobectomy participated in this study. Eligibility criteria were developed to ensure that only patients with the potential of achieving specific outcomes were included in the corresponding analyses.
Results: After surgery, significantly more patients were independent in activities of daily living (p < 0.001) or able to drive (p < 0.001). Income from work also increased (p < 0.01). Nearly one fifth of the patients who were eligible for analysis had either a gain (8%) or a loss (11%) of full- or of part-time work. Univariate analyses revealed the following factors to be associated with full-time work after surgery: student or full-time work within a year before surgery, full-time work experience before surgery, full- or part-time employment experience before surgery, no disability benefits before surgery, low post-surgical seizure frequency, improved postsurgical seizure control, excellent postsurgical seizure control, driving after surgery, and further education after surgery (p < 0.05). Significant factors on multivariate analysis were being a student or having full-time work within a year before surgery [odds ratio, 16.2 (95% CI, 4.3–60.5)], driving after surgery [15.2 (3.2–72.0)], and obtaining further education after surgery [9.2 (2.2–53.0)].
Conclusions: Anterior temporal lobectomy for intractable epilepsy improves activities of daily living and the ability to drive. Work outcome of this surgery is influenced by presurgical work experience, successful postsurgical seizure control especially to allow driving, and obtaining further education after surgery.     

Anterior Temporal Lobectomy and Medically Refractory Temporal Lobe Epilepsy of Childhood

The evaluation and outcome of 22 patients who had onset of complex partial seizures (CPS) of temporal lobe origin in childhood and subsequently underwent anterior temporal lobectomy are described. All patients showed improved seizure control; 81.8% had a reduction greater than or equal to 95% in seizure frequency. However, many patients had difficulty adjusting to a seizure-free life. Psychosocial, behavioral, and educational problems occurred more frequently in patients whose surgery was delayed until adult life. We conclude that attempts should be made early in the course of CPS of childhood to determine whether the seizures are truly intractable to medical management so that surgical intervention can be expedited.     

Extent of Resection in Temporal Lobectomy for Epilepsy. I. Interobserver Analysis and Correlation with Seizure Outcome

The extent of resection was assessed in 45 temporal lobectomies for medically intractable epilepsy with mapped temporal lobe foci. Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify the extent of resection of superior lateral, inferior lateral, basal, and medial structures, including the amygdalohippocampal complex. A new 20-compartment model of the temporal lobe was used for this assessment. Blinded interobserver variability was minimal. Intraoperative measurements and maps routinely overestimated the actual extent of resection, especially of medial structures. One year after surgery, 70% of patients remained seizure-free (except for auras). Seizure-free outcome was accomplished despite varying degrees of resection, but was more likely achieved with more extensive resections in all compartments. Among patients with mesiobasal foci, seizure-free outcome correlated significantly with extent of resection of amygdalohippocampal complex. We conclude that assessment of extent of resection by postoperative MRI provides an objective basis of evaluating outcome after temporal lobectomy. It allows a rational approach to understanding of operative failures and is potentially useful in comparing efficacy of various surgical approaches.     

Extent of Resection in Temporal Lobectomy for Epilepsy. II. Memory Changes and Neurologic Complications

We present correlations of extent of temporal lobectomy for intractable epilepsy with postoperative memory changes (20 cases) and abnormalities of visual field and neurologic examination (45 cases). Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify anteroposterior extent of resection of various quadrants of the temporal lobe, using a 20-compartment model of that structure. The Wechsler Memory Scale-Revised (WMS-R) was administered preoperatively and postoperatively. Postoperative decrease in percentage of retention of verbal material correlated with extent of medial resection of left temporal lobe, whereas decrease in percentage of retention of visual material correlated with extent of medial resection of right temporal lobe. These correlations approached but did not reach statistical significance. Extent of resection correlated significantly with the presence of visual field defect on perimetry testing but not with severity, denseness, or congruity of the defect. There was no correlation between postoperative dysphasia and extent of resection in any quadrant. Assessment of extent of resection after temporal lobectomy allows a rational interpretation of postoperative neurologic deficits in light of functional anatomy of the temporal lobe.     

Contribution of Neuropsychological Data to the Prediction of Temporal Lobe Epilepsy Surgery Outcome

Summary: Purpose: We empirically examined the contribution of neuropsychological data to the prediction of postoperative seizure control relative to base rate information in an existing series of patients undergoing anterior temporal lobectomy (ATL).
Methods: A discriminant function predicting surgery outcome (seizure-free vs. non-seizure-free) was computed separately for samples of patients with left (n = 79) and right (n = 62) temporal lobectomy (LATL, RATL). Predictor variables included 14 measures tapping five neurocognitive domains. The predicted base rates were compared with the actual base rates in the two samples. Finally, overall predictive accuracy was examined in optimal versus suboptimal ATL patients.
Results: The base rate of seizure freedom in the LATL group was 74.70%; that in the RATL group was 66.10%. The predictive function for the LATL group achieved a hit rate of 80.00% and a positive predictive power of 92.1 1%. The function for the RATL group achieved a hit rate of 83.33% and a positive predictive power (PPP) of 89.66%. The overall predictive accuracy for the optimal group was only 55%, but that in the suboptimal group was 72%.
Conclusions: Neuropsychological data used in a multivariate statistical fashion may be able to offer an incremental increase in the prediction of postoperative seizure freedom relative to existing base rates of surgery success in patients with ATL epilepsy. The use of neuropsychological data may be of greatest predictive value in a population of ATL candidates with suboptimal findings with a lower base rate of postoperative seizure freedom, but may actually reduce predictive accuracy in a group of ATL candidates from an optimal population with an already high base rate of surgical success.     

Indication for Anterior Temporal Lobectomy in Patients with Temporal Lobe Epilepsy and Psychopathology

Summary: The chronicity and severity of epilepsy, as well as the presence of temporal lobe foci, appear to correlate with psychopathology. A high prevalence of psychopathology has been reported among patients who are candidates for anterior temporal lobectomy (ATL). A review of the literature indicates that episodic psychosis may diminish when patients become free of seizures after surgery and that chronic psychosis neither improves nor worsens after ATL. If this is the case, patients with episodic psychosis may benefit from ATL. Patients with chronic psychosis may benefit if they become free from seizures after the operation, even if the psychosis persists. Case reports of maladjustment to seizure-free life after surgery, and de novo psychopathology, underline the importance of preop-erative psychiatric evaluation and postoperative psychiatric intervention in patients undergoing epilepsy surgery. Although there is a need for each epilepsy center to state its policy with regard to patients with psychopathology who undergo epilepsy surgery, it would be unwise to make a decision on whether to reject a patient simply on the grounds of psychosis. A detailed psychiatric evaluation of each individual patient is required.