MR imaging findings after transplant surgery for Parkinson disease

The authors describe the magnetic resonance (MR) imaging appearance of the head of the right caudate nucleus in patients who have undergone adrenal medullary transplant surgery for Parkinson disease. All four patients examined showed some clinical improvement after surgery. The MR images acquired 4-6 months postoperatively showed no evidence of caudate atrophy. Three of the four patients showed some increase in size of the operated caudate head relative to preoperative studies. Neither cavitation nor high signal intensity on T2-weighted images was evident within the caudate head. The one patient studied after administration of gadopentetate dimeglumine showed no abnormal enhancement. These images provided a description of the transplant site and also suggested that the clinical improvement seen was not due to simple ablation of caudate tissue or to postoperative inflammation. The increase in size of the caudate head also suggested that some implanted tissue may have remained in these patients at the time the MR images were acquired.