Behavioral complications of early pallidotomy

A review of stereotactic medial pallidotomy of the 1950s in five neurosurgical centers is presented. The surgical technique varied from one center to the other. The results of surgery, however, seemed to be quite equal, being positive in 70-90% of the patients. The surgical mortality ranged from 0 to 13%. Behavioral complications were adequately analyzed and reported from one center only and published by three independent neurologists. The side effects included drowsiness (12%), confusion (13.6%), mental deterioration (5%), memory deficit (13.6%), and dysphasia (7.5-24%, the rate depending on the concomitant brain atrophy). Among permanent side effects, 5% of the patients presented with a mild postoperative mental deterioration, whereas 13.6% had a severe memory deficit. In the four other centers, the results and side effects were analyzed only by the surgeons and were more biased. A comparison of the results and complications between Leksell's early medial pallidotomy of 1951-1957 and recent medial pallidotomies of the 1990s from two centers showed that 40 years ago Leksell had at least as good results as, and less serious complications than, two representative neurosurgeons of today. Even when positive clinical results of GPi pallidotomy have recently been reported from several centers, the patients seem to have improved relatively little, the dyskinesias excepted, and the rate of side effects has been quite high. The author is afraid that medial pallidotomy will soon be abandoned as a method of choice in the surgical treatment of Parkinson's disease, as in fact happened 40 years ago. One should look for better surgical alternatives and targets outside of the medial pallidum.