Abstract: Objective To assess the predictive value of acute stepwise levodopa challenge test on the outcome of deep brain stimulation in patients with Parkinson's disease(PD).Methods 65 patients with PD underwent acute stepwise challenge test with oral levodopa/benserazide 100/25 mg,150/37.5 mg,200/50 mg and 300/75mg respectively.And then they were implanted bilateral deep brain stimulation(DBS).The concordance between the results of acute levodopa challenge test and the outcome of DBS were evaluated after 24 months of follow-up.Results The result of the tests with levodopa/benserazide 150/37.5 mg,200/50 mg and 300/75 mg showed statistically significant concordance with the outcomes of DBS,with Kappa value being 0.373,0.642 and 0.849 respectively(P<0.01).But the result of the test with levodopa/benserazide 100/25 mg did not showed significant concordance with the outcomes of DBS,with Kappa value being 0.221(P>0.05).Conclusion The new acute stepwise levedopa challenge test could predict the outcome of DBS and should be used as a tool for screening appropriate candidates for DBS.

Key words: Parkinson's disease, acute stepwise levodopa challenge test, deep brain stimulation