Effect of Visible Light Therapy in Stroke Patients

OBJECTIVE: The aims of this study was to evaluate the effects of visible light therapy for the stroke patients. METHOD: Thirty stroke patients were enrolled and classified into two groups, experimental (n=19) and control group (n=11). Control group received conventional rehabilitation therapy. Experimental group received additional light therapy with red light (intensity 962 lux, wave length 620 nm) on wrist, elbow, and shoulder joint area (diameter 10 cm) at the same time, 3 times per day, 20 minutes per session, 5 days per week, for 2 weeks. All patients were assessed their paralytic upper extremity functions using manual muscle testing, two point discremination test (2-PD), Semmes-Weinstein monofilament test, and modified Ash-worth scale. To evaluate neurophysiological effects of light therapy, sympathetic skin response, thermography, and doppler ultrasound on radial artery were performed. RESULTS: Compared to the control group, the experimental group significantly improved in the 2-PD test, Semmes-Weistein monofilament test, and the hand grip power. Neurophysiologic parameters showed no significant difference between experimental and control groups. CONCLUSION: Visible light therapy maybe used as an effective therapeutic modality for improving hand function of stroke patients. Further studies are required to define the mechanism of effects on paralytic extremity of visible light.

Effect of Visible Light Therapy in Patients with Somatic Pain

OBJECTIVE: The purpose of this study is to evaluate the effect of visible light therapy for the management of somatic pain. METHOD: Subjects consisted of 42 patients with pain and were divided into two groups; control (n=22) and experimental (n=20) groups. Control group received conventional physical therapy only, while experimental group received additional light therapy with blue light (light intensity 4080 lux, wave length 581 nm, distance from lamp 5 cm). Intensity of pain was assessed by visual analogue scale (VAS) and McGill pain questionnaire. Sympathetic skin response was measured to assess the status of autonomic nervous system. VAS and McGill pain questionnaire were administered before treatment and at 1 day, 2 days, 3 days, 1 week, and 2 weeks after treatment. Sympathetic skin response were performed before and 2 weeks aftertreatment. RESULTS: 1) In both experimental and control groups, VAS became significantly lower at two weeks after treatment compared to pretreatment scale (p<0.05). 2) McGill pain questionnaire showed significantly lower scores two weeks after treatment compared to pretreatment score, only in experimental group (p<0.05). 3) Experimental group showed significantly lower McGill pain questionnaire score than control group at two weeks after treatment (p<0.05). 4) Latency and amplitude of sympathetic skin response showed no significant difference between experimental and control groups. CONCLUSION: Visible light therapy can be used as an effective therapeutic modality for the management of symptomatic pain in combination with conventional physical therapy.