Purpose: The occurrence of psychiatric symptoms after temporal lobectomy is well documented. The aim of the present study was to identify preoperative factors that predict postoperative psychiatric outcome.
Methods: We studied the case notes of 121 patients (from an initial sample of 167) who underwent temporal lobectomy at the National Hospital of Neurology and Neurosurgery, Queen Square, London, between 1988 and 1997. Data concerning gender, laterality of lesion, pathology, seizure outcome, psychiatric history, psychiatric outcome, resection volume, telemetry, and MRI scans were systematically collected. Factors that predict the occurrence of postoperative psychiatric symptomatology were investigated using correlational, chi(2), and logistic regression techniques.
Results: Poor postoperative psychiatric outcome in general was positively associated with preoperative bilateral independent spike discharges at telemetry. The size of surgical resection was positively correlated with the occurrence of postoperative emotional lability. The laterality of the epileptogenic lesion was not associated with a poor psychiatric outcome. Developmental lesions were associated with a good psychiatric outcome at a marginally significant level. Patients with a preoperative psychiatric history and de novo psychiatric symptomatology had a poorer surgical outcome in terms of seizure frequency, also at a marginally significant level. A significant correlation was found between a past psychiatric history and seizure outcome.
Conclusions: We identified a high frequency of psychiatric symptoms both before and after temporal lobectomy, demonstrating that it is not a benign procedure from the point of view of psychopathology. Our results show that there are certain predictive factors that may help identify patients most at risk for postoperative psychiatric disorders.