A PROSPECTIVE CLINICAL-STUDY OF STEREOTAXIC SUBCAUDATE TRACTOTOMY

This study describes a cohort of 23 patients undergoing stereotactic s ubcaudate tractotomy. Research Diagnostic Criteria indicated that 70% suffered major depressive disorder; the remainder mostly had a bipolar affective disorder. There were serial assessments pre-operatively and at 2 weeks and 6 months post-operatively using the Hamilton Rating Sc ale for depression, the Present State Examination (PSE), Newcastle Sca le, the Beck Depression Inventory, and the Taylor Manifest Anxiety Sca le. Neuropsychological assessment included tests thought to be sensiti ve to frontal lobe dysfunction, as well as tests of general intelligen ce, attention, memory, language and visuo-spatial function. Post-opera tively, depression rating scale scores decreased significantly but mos t patients continued to exhibit a number of PSE syndromes. Depression rating scale scores were correlated with 1 year global outcome: there was no significant correlation except for the 6 month assessment when lower Hamilton scores were found to be associated with better global o utcome. Correlations between the neuropsychological tests and the Hami lton and Beck depression scales at 2 weeks postoperatively suggested t hat an improvement in psychiatric condition was associated with greate r efficiency on some tests of attention and verbal recall, as well as faster performance on a sorting task. By contrast, the changes at 6 mo nths suggested an association between improvement in psychiatric condi tion and less efficient performance on certain neuropsychological test s including verbal recognition memory, attention and two tests of fron tal lobe dysfunction.