Adverse events following neurosurgery

Matthews & Eljamel (2003) gave an excellent overview of the controversial field of neurosurgery for mental disorders (NMD). I agree with them that ‘the accumulated literature on neurosurgery for mental disorder remains highly unsatisfactory’ but would like to point to some recent evidence.

Matthews & Eljamel state that ‘there is surprisingly little evidence’ to support the occurrence of adverse personality change. In my opinion, some of the literature suggests otherwise. Herner (1961) noted that in a group of 116 capsulotomy cases, frontal lobe deficit syndrome was obvious at follow-up in 30%. In the anxiety group, 40% and 13%, respectively, had adverse events of mild and of modest severity. In another study (Kullberg, 1977), capsulotomy caused ‘some personality changes in the majority of the patients’. Adverse events in those studies included fatigue, emotional blunting, emotional incontinence, indifference, low initiative, disinhibition and impaired sense of judgement.

In a very recent study (Rück et al, 2003), 26 anxiety patients who had undergone bilateral thermocapsulotomy were followed up after a mean of 13 years. Psychiatric methods included symptom rating scales and neuropsychological testing. To avoid bias, ratings were done by psychiatrists not involved in patient selection and postoperative treatment. Seventeen of 23 patients alive at long-term follow-up were seen in person and relatives were interviewed. The reduction in anxiety ratings was significant both as 1-year and long-term follow-up. Seven patients were, however, rated as experiencing significant adverse events, the most prominent symptoms being apathy and dysexecutive behaviour; also neuropsychological performance was significantly worse in these patients. I therefore agree with Matthews & Eljamel that we must continue to evaluate the efficacy and safety of NMD.