BILATERAL MOTOR IMPROVEMENT AND ALTERATION OF L-DOPA EFFECT IN 2 PATIENTS WITH PARKINSONS-DISEASE FOLLOWING INTRASTRIATAL TRANSPLANTATION OF FETAL VENTRAL MESENCEPHALONE

Several recent reports have suggested that foetal ventral mesencephali c transplants could alleviate motor symptoms in patients with Parkinso n's disease. Expectations of future success must be clarified by preci se analysis of the extent and limitation of recovery associated with a n assessment of function of the graft using [F-18]fluorodopa (F-18-dop a) PET. Two patients with idiopathic Parkinson's disease, severely imp aired despite optimal medication, have been followed 10 and 17 months after stereotaxic unilateral intrastriatal transplantation of neural c ells dissociated from human foetal ventral mesencephalon. Analysis of the clinical evolution complied with the protocol established in the ' Core Assessment Program for Intracerebral Transplantation'. Both patie nts have benefited from the transplantation in their daily activities and in motor timed tests, although they still exhibit parkinsonian sym ptoms and require L-dopa therapy. This is associated with a gradual in crease in F-18-dopa uptake at the site of grafting. There are two majo r clinical changes: (i) a bilateral motor improvement for the speed of movements (the quality of movements improved almost exclusively on th e side contralateral to the graft); (ii) a change in the outcome of th e L-dopa treatment as exemplified by a postoperative transient period of heavy dyskinesias and subsequent additive actions of the two treatm ents. These results confirm that neural transplantation may be useful for patients with Parkinson's disease. The improvement recorded on the side ipsilateral to the graft does not match that observed on the con tralateral side and it is proposed that bilateral transplantation may be necessary. The existence of a transient postoperative period of hea vy dyskinesias suggests that the patients may benefit from a controlle d decrease of L-dopa intake after grafting.