[Effects of deep brain stimulation on urodynamic findings in patients with Parkinson's disease]

Electric stimulation therapy is one of the surgical treatments for Parkinson's disease whereby a chronic stimulating electrode is placed on the subthalmic nucleus (STN). Because medical treatments centered around L-dopa have limitations in severe Parkinson's disease, electric stimulation therapy is regarded as an appropriate treatment modality. Most Parkinson's disease patients experience lower urinary tract disorders such as urgency, daytime frequency or nocturia, due to detrusor overactivity. We conducted an International Prostate Symptom Score (IPSS) analysis and a pressure flow study (PFS) on 6 patients before and after a chronic stimulating electrode was placed on the STN and evaluated how the subjective symptoms and bladder functions changed. As a result, the IPSS total value, involuntary detrusor contraction threshold volume and maximum bladder capacity were all found to significantly improve (P<0.05). The average IPSS decreased from 11.2 to 7.0. The average involuntary detrusor contraction threshold volume increased from 90.7 ml to 172.7 ml. The average maximal bladder capacity increased from 104.0 ml to 177.2 ml. These findings suggest that the STN the positively contributes to an improvement in urinary function.