Abstracts

RATIONALE: Children with epilepsy are at increased risk of mental health problems but the psychiatric outcome of childhood epilepsy surgery has not been examined. The aim of this study is to establish the spectrum of psychiatric illness in children before and after temporal lobectomy.
METHODS: The case notes for all children who underwent temporal lobectomy at Great Ormond Street Hospital, London between 1992 and 1998 were reviewed independently by 2 professionals (a child psychiatrist and a paediatric neurologist) and a clinical rating scale was applied both pre and post-operatively to establish DSM-IV criteria psychiatric diagnoses. Relevant clinical information including post-operative outcome was obtained and EEG and neuro-imaging were reviewed. Children with progressive pathology were excluded.
RESULTS: 60 children (35 males = 58%; 32 left-sided lesions = 53%) fulfilled the study criteria who had undergone a total of 71 procedures with a mean age at first operation of 10.6 years. Mean age of seizure onset was 3.43 years. A DSM-IV psychiatric diagnosis was established in 50/60 (83%) of these children at some point. 43/60 (72%) had a DSM-IV mental health disorder diagnosis pre-operatively and 41/57 (72%) post-operatively (mean length of post-operative follow-up = 5.1 years; 3 were lost to follow-up). Pervasive developmental disorders (PDD) were present in 23/60 children (38%), disruptive behaviour disorder (DBD) in 36/60 (60%), ADHD in 16/60 (27%), oppositional defiant disorder/conduct disorder (ODD/CD) in 16/60 (27%) and emotional disorders in 15/50 (25%). There were 2 children each with eating disorders and conversion disorders and 1 child with psychosis.
Children with PDD had a younger age of seizure onset (1.74 years; p = [lt] 0.05) compared with children without PDD. PDD was significantly associated with right sided temporal lobe lesions and male sex. There was no relationship between type of pathology or seizure frequency and PDD. Increased epileptiform discharges during sleep and disturbed sleep architecture on EEG were associated with PDD. ADHD (39% vs 19%) and DBD (83% vs 46%) were more common amongst the children with PDD compared to those without but emotional disorders were less frequent (9% vs 35%). There was improvement in PDD post-operatively in 13/23 (57%) and deterioration in the disorder in 3/23 (13%).
ADHD and DBD were both more common amongst males (p = [lt] 0.05). Emotional disorders were most common amongst children with normal IQ (13/15) and evolved post-operatively in 67% (10/15) of cases. There was no relationship between the evolution of a new disorder or any change in the severity of psychiatric disorders and seizure outcome.
CONCLUSIONS: Mental health problems are very common amongst children undergoing temporal lobectomy for intractable epilepsy and are present in 83% in this study. There is a chance of emotional and behavioural improvement following surgery unrelated to seizure control. However, parents and patients should be counseled about the possibility of the emergence of new mental health disorders or a deterioration in existing psychopathology post-operatively, which may actually be part of the natural history of the disorder rather than the result of surgery itself.