• Sleep Medicine and Psychophysiology
• /
• v.6 no.1
• /
• pp.46-51
• /
• 1999

Objectives: Patients with premenstrual dysphoric disorder(or PMDD) have impairments of the social, occupational or academic function due to psychological or somatic symptoms, which have the characteristic pattern of symptom exacerbation in the week before menses begin and remission shortly after the onset of menses. In the chronobiological view, many researchers have assumed that the etiology of PMDD is the advanced circadian rhythm. It has been suggested that light has a therapeutic effect on PMDD, because evening light results in phase delay of circadian rhythm through the biochemical changes including melatonin. Methods: The authors investigated the therapeutic effect of light therapy on four patients with prospectively diagnosed PMDD by DSM-IV criteria using clinical psychiatric interview, Premenstrual Assessment Form(PAF) and Daily Rating Form(or DRF). In the evening(6:30pm-8:00pm), the 2,500 lux light administered for seven consecutive days during the symptomatic late luteal phase of menstrual cycle. Beck Depression Inventory(or BDI), Hamilton Rating Scale for Depression(or HAM-D), Spielberg State Anxiety Inventory(or SA), and DRF were evaluated before and after seven days of light therapy. Results: Premenstrual symptoms of PMDD could be effectively treated with the evening bright light therapy, especially in PMDD patients with atypical symptoms. In addition, the light therapy seemed to more effective on the psychologic symptoms than the somatic symptoms of PMDD. There was no significant side-effect of light therapy, except the transient and mild eye-strain in one case. Conclusions: In spite of the results of limited data from our clinical trial, the authors suggest that the potential use of light therapy as an alternative to the pharmacological management of patients with PMDD.

• Korean Journal of Psychosomatic Medicine
• /
• v.11 no.2
• /
• pp.196-204
• /
• 2003

Objectives: It is known that sedative hypnotics would make cross tolerance with alcohol and deteriorate quality of sleep in alcoholics. Light therapy is effective non-pharmacological intervention for sleep disturbance in circadian phase disorders, jet-lag, shift-work and age-related sleep disorders. Authors would investigate the effects of morning light therapy on sleep of patients with alcohol dependence during recovery state without withdrawal symptoms. Methods: 13 patients with alcohol dependence who have not any alcohol withdrawal symptom were recruited. Light therapy during 1 hour in the morning had been administered by 2500 Lux light box through serial 3 days. Sleep state of subjects were assessed by sleep log and the subjective satisfaction at sleep was by 100 mm visual analogue scale. Sleepiness, depressive mood, anxiety were evaluated by 100mm visual analogue scale at 8 AM, 2 PM and 8 PM. For assessment of performance ability that would be associated with sleepiness and vigilance, trail making test A, B and digit symbol substitution test were performed by two times on base line and 4th day. Univariate repeated-measures ANOVAs were performed for each measures except performance tests which were analysed by paired t-test. Results: Sleep latency and sleep efficiency were significantly improved with light therapy and satisfaction at sleep was. There was no significant difference in sleepiness at 2 PM with light therapy but sleepiness at 8 AM significantly decreased and at 8 PM increased. The time to complete Trail making test and digit symbol substitution test were significantly shortened at 4th day compared with baseline. Fatigue at 8 AM were not significantly changed with light therapy but at 2 PM and 8 PM significantly decreased. Depressive mood and anxiety were not significantly changed with light therapy. Conclusion: Although this study had some limitations, it showed that light therapy would be effective modality on sleep disturbance of patients with alcohol dependence who have recovered from alcohol withdrawal symptoms. It is proposed that short term light therapy could be used clinically for alcoholics with insomnia. In the future, long term controlled studies using more objective tools for sleep are required to further investigate the effect of light therapy in alcoholics.

• Korean Journal of Psychosomatic Medicine
• /
• v.8 no.1
• /
• pp.103-109
• /
• 2000

The authors identified a treatment-resistant patient with chronic fatigue syndrome, characterized by chronic fatigue, headache, unrefreshing sleep. Some studies reported that chronic fatigue syndrome was associated with affective disorder, especially seasonal affective disorder and many studies reported that bright light therapy was effective in seasonal affective disorder. But efficacy of light therapy for chronic fatigue syndrome was rarely reported. We treated the patient with morning light treatment using 2500lux light box, the clinical symptoms in this case were improved. The authors suggest that the light therapy can be a treatment modality for chronic fatigue syndrome.

• Electronics and Telecommunications Trends
• /
• v.25 no.5
• /
• pp.59-71
• /
• 2010

피부질환 치료를 위한 광선요법은 태양광, 레이저, 형광등, UV 램프 등 다양한 광원을 이용하여 광이 피부 내에서 생화학적 반응을 촉진하는 원리를 이용하여 피부 조직의 선택적 재생 또는 파괴 등을 통해 손상된 피부를 치료하는 광 의료 기술이다. 최근 발전하고 있는 LED 광원 기술은 광선요법에서 시용되어온 광원을 대체할 수 있는 기술로 각광을 받고 있다. 이에 본 고에서는 광선요법과 관련된 기초 원리를 살펴보고, LED가 피부질환 치료용 광원으로 사용될 때 고려되어야 하는 임상적, 기술적 문제점과 다양한 피부질환 치료에 있어서 LED 광원의 역할에 대해 살펴 보았다. 아울러, 피부질환 치료용 LED 치료기 관련 국내외 연구 개발 동향과 기업들이 출시한 LED 치료기의 특성을 살펴보았다. LED 치료기 관련 표준화 동향과 국내외 지식재산권 현황을 살펴보았으며, 향후 LED 기반의 피부질환 치료기의 개발 방향을 모색하였다.

• Sleep Medicine and Psychophysiology
• /
• v.9 no.1
• /
• pp.41-47
• /
• 2002

Objectives: In a number of simulated night shift studies, timed exposure to bright light improves sleep quality and work performance. We evaluated the effect of bright light on adaptation to night shift work with a field study. Methods: Five female nurses working shifts at Korea University Hospital were recruited for participation in this study. We investigated two series of six consecutive shift rotations comprising three day and three night shifts, using wrist Actigraphy, the Stanford Sleepiness Scale, Visual-analogue scales, STIM and tympanic membrane temperature for daytime sleep quality, alertness, subjective feeling, attention performance, and temperature rhythm. The subjects were exposed to bright light (2,500 lux) from 24:00 to 04:00 a.m. on three consecutive night shifts during the second series, whereas they worked under normal lightening (650 lux) conditions during the first series. Results: Actigraphic assessment of daytime sleep showed no significant difference between the first and third night shift in both baseline and light exposure phase. The mean lowest temperature shifted earlier during baseline phase but not during the light exposure phase. Also, the score for subjective feelings of depression, anxiety, physical discomfort and sleepiness was significantly higher in the third night shift than the first during baseline phase but not during the light exposure phase. Attention and attention switching ability was significantly improved in the third night shift compared to the first night during the light exposure phase but there were no significant changes during the baseline phase. Conclusion: This result suggests that there were no significant differences between the two phases in measures of quality of daytime sleep, but subjective feelings, attention and alertness were enhanced during light exposure. Although some placebo effects and learning effects might influence this result, bright light exposure between midnight and 4:00 a.m. may improve adaptation to night shift. In future, further controlled studies with a larger sample size, including melatonin measurement, are needed for real shift workers.

• Sleep Medicine and Psychophysiology
• /
• v.10 no.1
• /
• pp.20-25
• /
• 2003

Many people suffer from chronic insomnia. Inappropriate sleep causes attention difficulties, decreased work efficiency, and increased traffic accidents and disasters. Evaluating the precise causes of insomnia prior to treatment is very important, because chronic insomnia can be a secondary symptom of other medical, psychiatric, and sleep disorders. Medication and behavior therapy are not exclusive of each other, and both treatments are beneficial to some patients, but currently many physicians and patients tend to be dependent only on medication. While long-term medication causes various degrees of dependency, tolerance, and withdrawal symptoms, behavior therapy has a stable effect over a long period. Behavior therapy is one of the most important treatment modalities for chronic insomnia. It shortens sleep latency, and decreases frequency of awakening during sleep. The rationale and practice of currently used behavior therapy and light therapy will be reviewed in this study.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.39 no.3
• /
• pp.233-241
• /
• 2012

Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. The aim of this study was to evaluate the effect of PDT on Streptococcus mutans in planktonic conditions, previously treated with different photosensitive concentrations of erythrosine, using halogen and LED curing unit as a light source. And we compared the effects of PDT on six strains of S. mutans isolated from oral cavity and reference strain. As a result, S. mutans was susceptible to the combination of hand held photopolymerizer (HHP) and erythrosine. The higher concentration of erythrosine in the presence of light irradiation induced greater effects in reduction of viability of S. mutans. Isolated S. mutans showed a significant reduction in bacterial counts of the groups submitted to PDT compared to the control groups. And they appeared to be similar or slightly lower antimicrobial effect compared with reference strain. However, the difference was not significant (p < 0.05). In conclusion, PDT using erythrosine as a photosensitizing agent and HHP as a light source could be an efficient option for diseases caused by S. mutans.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.539-541
• /
• 2022

Photodynamic therapy is one of the ways to treat cancer using light and during laser irradiation, photosensitizers react and combine with oxygen to destroy cancer cells. This treatment is in the spotlight as a treatment that minimizes side effects in cancer patients. Among them, photosensitizers differ in the treatment area, treatment effect, and degree of absorption depending on the type. Therefore, in this study, a quantitative evaluation study was conducted on the effect of inhibiting cancer cell proliferation by irradiating blue LEDs on HELA cell lines injected with 5-ALA among photosensitizers.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.9
• /
• pp.1237-1242
• /
• 2018

Photodynamic therapy has been suggested as an alternative treatment to current cancer therapy which resulting in a variety of side effects because photodynamic therapy targets specific cancer cells and does not have a significant effect on normal cells. Typically, laser was used as a photodynamic therapy, but this was limited due to high cost and heat reaction. However, compact light emitting diodes that can emit light of various wavelengths have been developed at a low cost, which has a great influence on the low cost development of photodynamic therapy equipment. On the other hand, in the study of photodynamic therapy, the data on the direct effect of visible light are relatively small. Therefore, in this paper, we propose a novel cancer therapeutic module by developing a cancer cell proliferation inhibition module based on an Arduino that is relatively inexpensive, and able to use light of various wavelengths.

• Sleep Medicine and Psychophysiology
• /
• v.15 no.1
• /
• pp.12-16
• /
• 2008

Light therapy (also called light treatment or phototherapy) involves scheduled exposure to bright artificial light. Evidence-based treatments for sleep disorders especially for circadian rhythm sleep disorders include light therapy and pharmacotherapy. In clinical practice, many of patients with sleep problems tend to impair circadian rhythmicity. Considering that light is the most potent entraining agent of circadian rhythm, careful use of light therapy can be recommended for patients with several kinds of sleep disorders. I briefly review the possible therapeutic mechanisms and clinical applications of light therapy, focusing on circadian sleep disorders.