When thalamotomy is employed, approximately 85 percent to 90 percent of patients have relief of tremor, while only about 50 percent have improvement of rigidity and bradykinesia. Neurological complications are usually temporary. When bradykinesia, rigidity, or drug-induced dyskinesias are the most disabling symptoms, pallidotomy is the procedure of choice. Pallidotomy also improves tremor. Over 70 percent of patients are improved for at least one year.
Serious complications occur in less than five percent of patients.
M.D. Dementia is common in Parkinson's disease, occurring in up to 40 percent of affected patients. There is considerable overlap of Parkinson's disease and Alzheimer's disease with up to 35 to 45 percent of patients with Alzheimer's disease showing some of the pathological features of Parkinson's disease. Features of Parkinson's and Alzheimer's The major histopathologic feature of Parkinson's disease is the presence of Lewy bodies-round, eosinphilic cytoplasmic inclusions in the substantia nigra and locus ceruleus. The major histopathologic features of Alzheimer's disease are senile plaques and neurofibrillary tangles in the cerebral neocortex, hippocampus, amygdala and entorhinal cortex. The clinical features of Parkinson's disease are rigidity, bradykinesia and tremor, compared with clinical features of Alzheimer's disease, which are decline in memory, abstract thinking, judgment, problem solving and language, visuospatial alterations, and behavioral changes.