Digital polysomnography was developed to overcome the limitations of Rechtschaffen and Kales rule and to compensate the shortcomings of paper polysomnography. It enables easy access to and secure preservation of sleep records, and provides various displays of sleep data to enhance efficiency of visual scoring of sleep records. Rechtschaffen and Kales rule had been criticized for its ambiguity and lack of considerations in spatial information of EEG. As sleep records are acquired and processed in digital mode, they can be analyzed at microscopic and macroscopic levels. Digital analysis of sleep records provides the basis for development of new sleep measures. Sleep staging in digital polysomnography is based on the various analyses of EEG. Sleep apnea, hypopnea and periodic limb movement are detected automatically by digital analysis of respiratory signals and leg EMG. Digital polysomnography plays a complementary role to visual scoring and compensates the limitations of paper polysomnography. Digital polysomnography, including acquisition, processing and analysis of sleep records in digital mode, can be a great help in the development of sleep medicine, enabling the development of new sleep measures and the exchange of sleep records between sleep laboratories.
Brassica ; Electroencephalography ; Extremities ; Leg ; Polysomnography* ; Sleep Apnea Syndromes

No abstract available.
Angina, Stable* ; Tumor Necrosis Factor-alpha*

Adenotonsillar hypertrophy is the leading cause of childhood obstructive sleep apnea. Obstructive sleep apnea syndrome in child-hood, however, can occur from various causes such as obesity or craniofacial abnormalities. Childhood obstructive sleep apnea syndrome can be accompanied by enuresis, parasomnias and behavior problems. For patients with the symptoms of snoring and apnea, obstructive sleep apnea should be suspected and diagnosed properly. In addition, the evaluation of complications and proper treatment are indispensable. When the cause of childhood obstructive sleep apnea is adenotonsillar hypertrophy, symptoms can be improved by surgical methods. If the cause is other than adenotonsillar hypertrophy, such as obesity, it should be treated with other therapeutic modalities, like nasal continuous positive airway pressure (nCPAP), weight reduction and modification of life style. This paper reports a case of nCPAP used to manage severe sleep apnea when it was not resolved after adenoidectomy and tonsillectomy. Differential diagnosis of narcolepsy in a case with excessive daytime sleepiness and reflections on accompanying enuresis and parasomnia were also described.
Adenoidectomy ; Apnea ; Child ; Continuous Positive Airway Pressure ; Craniofacial Abnormalities ; Diagnosis, Differential ; Enuresis ; Humans ; Hypertrophy ; Life Style ; Narcolepsy ; Obesity ; Parasomnias ; Sleep Apnea Syndromes ; Sleep Apnea, Obstructive* ; Snoring ; Tonsillectomy ; Weight Loss

INTRODUCTION: Although it is well known that medical students are not getting an adequate amount of sleep, there have been only few studies on the sleep patterns of medical students in Korea. Therefore, the present study aimed to investigate the life style and sleep patterns of Korean medical students and the impact they have on the students' academic performance. METHODS: A questionnaire package was administered to the 3rd year medical students at the Seoul National University to examine their sleep patterns on weekdays and weekends. It consisted of questions asking about their lifestyles as well as Pittsburgh sleep quality index (PSQI) and GPA (Grade Point Average) that are considered relevant to their sleep patterns. A total of 110 students (85 males and 25 females, mean age 24.4+/-20.6) responded to the survey and the result was analyzed using the independent t-test, the chi-square test, the paired t-test, Pearson's rank correlation and ANOVA. P-values of less than 0.05 were considered statistically significant in all analyses. RESULTS: The weekend bedtime was significantly delayed (01:24 on weekday; 03:12 on weekend; t=-5.23, p<0.01), the weekend rise time was delayed (07:36 on weekday; 10:30 on weekend; t=-24.48, p<0.01) and the total sleep time was increased on weekends (5:57 on weekday; 8:17 on weekend; t=15.94, p<0.01). They wished to sleep for 7 hours 6 minutes which was different from their actual weekday total sleep time (t=-11.41, p<0.01). The poor sleeper group had lower GPAs than the good sleeper group (t=2.05, p<0.05). The GPA of medical students were negatively correlated with age (r=-0.23, p<0.05), daily amount of smoking (r=-0.78, p<0.01), total amount of smoking (r=-0.75, p<0.01), weekday sleep latency (r=-0.23, p<0.05), weekend sleep latency (r=-0.23, p<0.05) and PSQI score (r=-0.30, p<0.01). CONCLUSION: Medical students were experiencing a lack of sleep during weekdays as they have a later bedtime and earlier rise time, and consequently had more hours of sleep on weekends. Overall, the responded students were experiencing poor sleep quality, and the GPAs of the poor sleeper group were lower than those of the good sleeper group.
Female ; Humans ; Korea ; Life Style ; Male ; Surveys and Questionnaires ; Smoke ; Smoking ; Students, Medical

INTRODUCTION: Detrended fluctuation analysis (DFA) is used as a way of studying nonlinearity of EEG. In this study, DFA is applied on sleep EEG of normal subjects to look into its nonlinearity in terms of EEG channels and sleep stages. METHOD: Twelve healthy young subjects (age: 23.8+/-2.5 years old, male:female=7:5) have undergone nocturnal polysomnography (nPSG). EEG from nPSG was classified in terms of its channels and sleep stages and was analyzed by DFA. Scaling exponents (SEs) yielded by DFA were compared using linear mixed model analysis. RESULTS: Scaling exponents (SEs) of sleep EEG were distributed around 1 showing long term temporal correlation and self-similarity. SE of C3 channel was bigger than that of O1 channel. As sleep stage progressed from stage 1 to slow wave sleep, SE increased accordingly. SE of stage REM sleep did not show significant difference when compared with that of stage 1 sleep. CONCLUSION: SEs of Normal sleep EEG showed nonlinear characteristic with scale-free fluctuation, long-range temporal correlation, self-similarity and self-organized criticality. SE from DFA differentiated sleep stages and EEG channels. It can be a useful tool in the research with sleep EEG.
Electroencephalography* ; Polysomnography ; Sleep Stages ; Sleep, REM

INTRODUCTION: Excessive daytime sleepiness and cataplexy are key features of narcolepsy. Modafinil is psychostimulant used in the treatment of narcolepsy. In this study, we evaluated effects of modafinil on nocturnal sleep structure and sleep latency in multiple sleep latency test and clinical features. METHODS: Twelve narcoleptic patients (7 male, age: 22.9 +/- 2.6 yrs) were participated in the study. All of them had done nocturnal polysomnography (nPSG), multiple sleep latency test (MSLT), clinical symptoms scales and have repeated same procedure after taking 200 mg of modafinil. We have done linear mixed model analysis to describe effects of group, medication and nap time on these measures. RESULTS: Modafinil did not affect clinical scales except PSQI which had been reduced after medication. In this study, Modafinil reduced total sleep time, sleep efficiency and increased wake after sleep onset and percent of arousal during sleep in nocturnal polysomnography and prolonged mean sleep latency in multiple sleep latency tests in both group. DISCUSSION: Modafinil has stimulant effect of central nervous system but its effect on night sleep is less than other psychostimulants such as methylphenidate. We ascertained that modafinil affected total sleep time, sleep efficiency and percent of wake during sleep but did not effect on sleep structure. Modafinil was effective in the management of day time sleepiness. Modafinil can enhance alertness of control group without day time sleepiness.
Arousal ; Cataplexy ; Central Nervous System ; Humans ; Male ; Methylphenidate ; Narcolepsy* ; Polysomnography ; Weights and Measures

BACKGROUND: The implementation of intraoperative normovolemic hemodilution is a strategy used in an attempt to diminish the need for or obviate allogeneic transfusion and to avert the potential complications. The goal of this study was to evaluate the safety and efficacy of moderate intraoperative normovolemic hemodilution. METHODS: Fifteen patients scheduled for posterolateral spinal fusion underwent intraoperative normovolemic hemodilution with 10% pentastarch to a target hematocrit level of 25% (hemodilution group). All units of blood procured by hemodilution and additional allogeneic blood was transfused in the perioperative period to maintain the hematocrit level of>25%. We investigated the effect of hemodilution on whole blood coagulation as measured by the thromboelastography and, evaluated its efficacy of decreasing the need for allogeneic blood transfusion as compared to the nonhemodilution group, retrospectively. RESULTS: Hemodilution with pentastarch caused a decrease in response and coagulation time (p<0.01) but did not influence on the alpha angle and maximum amplitude on thromboelstogram. Amount of transfusion of allogeneic blood was 4.1 1.7 units for the hemodilution group and 5.0 1.5 units for the nonhemodilution group. Net red blood cell volume ""saved"" from hemodilution was about 120 ml. CONCLUSION: Moderate intraoperative normovolemic hemodilution with pentastarch does not affect the coagulability of whole blood. But its efficacy of decreasing the need for allogeneic blood transfusion is minimal.
Blood Coagulation ; Blood Transfusion ; Erythrocytes ; Hematocrit ; Hemodilution* ; Humans ; Hydroxyethyl Starch Derivatives ; Perioperative Period ; Retrospective Studies ; Spinal Fusion* ; Thrombelastography

No abstract available.
Child* ; Humans ; Syringoma* ; Vulva

In situ hybridization using biotinylated HPV(Human papillomaviruses) probes was performed to detect HPV DNA in 24 patients with genital wart-like lesions. The lesions were divided into two groups, with or without dysplastic changes histologically. We could detect HPV6/11 in 13 of 17 lesions(76.5%) without dysplastic changes. HPU16/18 was detected in a case with dysplastic changes. HPV6/ll was also detected in a case considered to be misdiagnosed as bowenoid papulosis. Oncogenic HPV such as HPV16/18 was found in one of histologically splastic lesions(14.3%).
Condylomata Acuminata* ; DNA* ; Humans* ; In Situ Hybridization

No abstract available.
Neoplasm Metastasis* ; Pancreatic Neoplasms* ; Scalp* ; Thorax*