Leucencephalopathy in Patients with Parkinson's Disease and Deep Brain Stimulation.

Background: Leucencephalopathy (LE) is often detected on magnetic resonance imaging in elderly patients. These white matter lesions may interfere with lead trajectories for deep brain stimulation (DBS) in patients with Parkinson's disease (PD) and are associated with complications after DBS surgery.

Objective: This study was conducted to assess the incidence of LE in PD patients and to evaluate correlations with complications after DBS surgery.

Methods: A consecutive cohort of PD patients who underwent DBS surgery in the subthalamic nucleus (STN-DBS) was retrospectively analyzed. The presence and extent of LE were quantified using the Fazekas scale. Postoperative complications were extracted from the medical records. DBS efficacy was calculated using the side-specific motor symptom ratio (Unified Parkinson's Disease Rating Scale, Part III, postoperative stimulation ON/medication off divided by preoperative medication off) at 1-year follow-up.

Results: A total of 135 PD patients were included in the study. LE was detected in 35.6% (48/135) of the patients. In 87.7% (57/65), LE was mild, in 10.7% (7/65) moderate, and in 1.6% (1/65) severe. A higher incidence of mild to moderate LE did not correlate with postoperative hemorrhage or postoperative infection. There was no correlation of LE with stimulation efficacy (r = -0.05, P = 0.69) or with surgical index (r = -0.10, P = 0.35).

Conclusions: Neither was the presence of mild to moderate LE associated with an increased risk for surgical complications, nor did it negatively impact the long-term improvement in motor function after DBS surgery in PD patients. Therefore, mild to moderate LE should not be considered a contraindication for DBS.