LONG-TERM IMPROVEMENT IN PATIENTS WITH SEVERE PARKINSONS-DISEASE AFTER IMPLANTATION OF FETAL VENTRAL MESENCEPHALIC TISSUE IN A CAVITY OF THE CAUDATE-NUCLEUS - 5-YEAR FOLLOW-UP IN 10 PATIENTS

Different groups worldwide have observed in recent years that stereota ctic implantation of fetal tissue can ameliorate the clinical symptoms of Parkinson's disease. The authors therefore investigated whether im plantation of fetal ventral mesencephalic (FVM) tissue via open surger y is also capable of producing an improvement and whether this improve ment is transient or long lasting. The authors report their findings i n a 5-year follow-up study in 10 patients with Hoehn and Yahr Grade N or V Parkinson's disease in whom a single FVM graft was implanted in a cavity created in the right caudate nucleus. The results indicate tha t the implants improved motor function and that clinical recovery pers isted in seven of the 10 patients 5 years after implantation. Ameliora tion was observed in both the on and off phases and was accompanied by a 64% reduction in the levodopa dose and withdrawal of the dopamine a gonist. The on phase was prolonged from 39% of the waking day to 72%, with reduced intensity and duration of dyskinesias. All symptoms that were analyzed showed improvement, although they differed in intensity and time of onset. The course of improvement seemed to be stepwise, wi th significant improvement between 5 and 7 months postimplantation fol lowing by two waves of process peaking in Months 15 and 36. Withdrawal of cyclosporine in three patients after more than 2 years of administ ration produced a decline in the patients' clinical conditions. In con clusion, the results indicate that open surgery implantation of FVM ti ssue in the caudate nucleus improves the clinical condition of parkins onian patients and that this improvement can persist for at least 5 ye ars. In comparison with two earlier series reported by the authors, wh ich involved implants of perfused adrenal medulla and coimplantation o f adrenal medulla and peripheral nerve, the course and pattern of impr ovement in these implant recipients suggests that their recovery can b e attributed to more than one factor.