Laserlight cues for gait freezing in Parkinson's disease: an open-label study.
Freezing of gait (FOG) and falls are major sources of disability for Parkinson's disease (PD) patients, and show limited responsiveness to medications. We assessed the efficacy of visual cues for overcoming FOG in an open-label study of 26 patients with PD. The change in the frequency of falls was a secondary outcome measure. Subjects underwent a 1-2 month baseline period of use of a cane or walker without visual cues, followed by 1 month using the same device with the laserlight visual cue. The laserlight visual cue was associated with a modest but significant mean reduction in FOG Questionnaire (FOGQ) scores of 1.25 ± 0.48 (p = 0.0152, two-tailed paired t-test), representing a 6.6% improvement compared to the mean baseline FOGQ scores of 18.8. The mean reduction in fall frequency was 39.5 ± 9.3% with the laserlight visual cue among subjects experiencing at least one fall during the baseline and subsequent study periods (p = 0.002; two-tailed one-sample t-test with hypothesized mean of 0). Though some individual subjects may have benefited, the overall mean performance on the timed gait test (TGT) across all subjects did not significantly change. However, among the 4 subjects who underwent repeated testing of the TGT, one showed a 50% mean improvement in TGT performance with the laserlight visual cue (p = 0.005; two-tailed paired t-test). This open-label study provides evidence for modest efficacy of a laserlight visual cue in overcoming FOG and reducing falls in PD patients.