PURPOSE: The present study examined how intraocular pressure is affected by changes in sleeping posture (22-2400 hours) from the sitting position to the supine, prone, and lateral positions in normal subjects. METHODS: Ophthalmological examination was performed on 140 eyes of 70 healthy adult men, and changes in the intraocular pressure were measured according to posture during sleep. The subject was initially relaxed and the base intraocular pressure was measured in the sitting position. In order to reduce the influence of intraocular pressure among the positions, namely, the supine, the prone, and the lateral recumbent positions, the subject was seated for ten minutes before assuming each position. Intraocular pressure was measured twice at 0 and 10 minutes in each position, and the mean of the two values was used for comparison. RESULTS: Compared to the intraocular pressure in the sitting position, intraocular pressure increased significantly in the supine, prone, and lateral positions (p< 0.05). Compared to the base intraocular pressure, the intraocular pressure measured in the prone position showed the largest difference, increasing 6.34 mm Hg in the right eye and 6.43 mm Hg in the left eye. The intraocular pressure measured in the lateral position was 3.62 mm Hg higher in the right eye and 3.63 mm Hg higher in the left eye, and that in the supine position was 2.42 mm Hg and 2.28 mm Hg higher in the right and left eyes, respectively. CONCLUSIONS: The change in posture during sleeping from the sitting position to the supine, prone, and lateral positions caused increases in intraocular pressure in normal subjects. The results show that the change in sleeping posture induced by sleeping habits may raise intraocular pressure.
Adult ; Eye ; Glaucoma ; Humans ; Intraocular Pressure ; Male ; Posture ; Prone Position ; Supine Position

PURPOSE: To investigate intraocular pressure (IOP) and ocular biometry change according to the posture change in healthy eyes. METHODS: Forty eight eyes of 48 healthy young subjects were enrolled. IOP, central anterior chamber depth (cACD), and axial length were measured after keeping each position for 10 minutes (upright, sitting, supine, and prone positions) by using the TonoPen(R) and A-scan ultrasonography. RESULTS: Mean IOP was 19.68 +/- 2.15 mm Hg in prone position, 17.19 +/- 1.33 mm Hg in supine position, 16.49 +/- 1.76 mm Hg in sitting position, and 15.33 +/- 1.34 mm Hg in upright position. Difference among the positions was statistically significant (p < 0.01). Mean cACD was 3.68 +/- 0.35 mm in upright position, 3.63 +/- 0.32 mm in supine position, 3.59 +/- 0.34 mm in sitting position, and 3.47 +/- 0.30 mm in prone position. Difference among the positions was statistically significant (p < 0.01) except for the difference between supine and sitting position. Linear regression analysis revealed that cACD was significantly associated with IOP in prone position (R2 = 0.139, p < 0.01). CONCLUSIONS: There was a significant change in IOP and cACD according to the posture change. cACD was significantly associated with IOP only in prone position.
Anterior Chamber ; Biometry ; Eye ; Intraocular Pressure ; Linear Models ; Posture ; Prone Position ; Supine Position

OBJECTIVE: Galvanic vestibular stimulation (GVS) activates the vestibular afferents, and these changes in vestibular input exert a strong influence on the subject's posture or standing balance. In patients with Parkinson's disease (PD), vestibular dysfunction might contribute to postural instability and gait disorders. METHODS: Current intensity was increased to 0.7 mA, and the current was applied to the patients for 20 minutes. To perform a sham stimulation, the current intensity was increased as described and then decreased to 0 mA over the course of 10 seconds. The patient's status was recorded continuously for 20 minutes with the patient in the supine position. RESULTS: Three out of 5 patients diagnosed with PD with postural instability and/or abnormal axial posture showed a reduction in postural instability after GVS. The score for item 12 of the revised Unified Parkinson's Disease Rating Scale part 3 was decreased in these patients. CONCLUSIONS: The mechanism of postural instability is complex and not completely understood. In 2 out of the 5 patients, postural instability was not changed in response to GVS. Nonetheless, the GVS-induced change in postural instability for 3 patients in our study suggests that GVS might be a therapeutic option for postural instability.
Gait ; Humans ; Parkinson Disease* ; Posture ; Supine Position

STUDY DESIGN: Cross-sectional study.PURPOSE: This was carried out to evaluate the benefit of a ‘fulcrum bending position’ compared with the standing position for evaluation of sagittal translation and sagittal rotation in symptomatic patients with spondylolisthesis.OVERVIEW OF LITERATURE: In lumbar X-ray, the standing position is the most common position used in determining abnormalities in lumbar movement. Lack of standardized method is one of the pitfalls in this technique. We hypothesized that the new technique, that is, fulcrum bending position, may reveal a higher translation and rotation in spondylolisthesis patients.METHODS: The extension lumbar radiographs of 36 patients with low-grade spondylolisthesis were included in the analysis and measurement. Sagittal translation and sagittal rotation were measured in both the routine standing position and in our new technique, the fulcrum bending position, which involves taking lateral cross-table images in the supine position wherein the patient lies on a cylindrical pipe to achieve maximum passive back extension by the fulcrum principle.RESULTS: Results of the measurement of sagittal translation in both positions revealed that compared with the extension standing position, the fulcrum bending position achieved a statistically significant increase of 1.57 mm in translation of the vertebra position (95% confidence interval [CI], 0.52–2.61; p=0.004). The measurement of sagittal rotation in both positions revealed that when compared with the extension standing position, the fulcrum bending position achieved a statistically significant increase of 3.47° in the rotation of the vertebra (95% CI, 1.64–5.30; p<0.001).CONCLUSIONS: For evaluation of both sagittal translation and sagittal rotation in symptomatic patients with spondylolisthesis, compared with the extension standing position, the fulcrum bending position can achieve an increased change in magnitude. Our technique, that is, the fulcrum bending position, may offer an alternative method in the detection or exclusion of pathological mobility in patients with spondylolisthesis.
Cross-Sectional Studies ; Humans ; Methods ; Posture ; Spine ; Spondylolisthesis ; Supine Position

BACKGROUND: Body posture, as a gravitational factor, has a clear impact on pulmonary ventilation and perfusion. In lung units with mismatched ventilation and perfusion, gas exchange and/or elimination of carbon dioxide can be impaired. In this situation, differences in the value of arterial and end-tidal carbon dioxide tension [Delta(PaCO2 - PETCO2)] are expected to increase. This study was conducted to observe how Delta(PaCO2 - PETCO2) changed according to the 3 different surgical positions, and to determine whether Delta(PaCO2 - PETCO2) is a reliable predictor of ventilation/perfusion mismatch when a patient is in different postural positions. METHODS: Fifty-nine patients were divided into either the chronic obstructive pulmonary disease (COPD) group (n = 29) or the non-COPD group (n = 30). PaCO2 and PETCO2 were measured during surgery in the supine, prone, and lateral decubitus positions after a 10 minute stabilization period. The Delta(PaCO2 - PETCO2) were calculated and compared among positions. RESULTS: The Delta(PaCO2 - PETCO2) decreased slightly in the prone position and increased significantly in the lateral decubitus position compared with the supine position in both groups. These patterns almost corresponded with the degree of ventilation/perfusion mismatch from the results of the radiological studies. The Delta(PaCO2 - PETCO2) in the COPD group was significantly greater than that in the non-COPD group at all surgical positions. CONCLUSIONS: Lateral decubitus position is associated with marked increase in Delta(PaCO2 - PETCO2), especially in patients with COPD. The Delta(PaCO2 - PETCO2) is a simple and reliable indicator to predict ventilation/perfusion mismatch at different surgical positions in patients with or without COPD.
Benzeneacetamides ; Carbon ; Carbon Dioxide ; Humans ; Lung ; Perfusion ; Piperidones ; Posture ; Prone Position ; Pulmonary Disease, Chronic Obstructive ; Pulmonary Ventilation ; Supine Position ; Ventilation ; Ventilation-Perfusion Ratio

It has been known that Korean adults have brachycephalus in their skull shape as compared with neighboring orientals. However, there is no difference between Korean newborn infants and other oriental newborn infants in skull shape. Acquired factors seem to be more important than hereditary factors as a possible cause of brachycephalus in Korean adults. In order to study the process of brachycephalization in the skull shape, I measured head girth, head length, head width and cephalic index. Those results were divided into three categories, namely, feeding, period of ingestion of undaria pinnatifida (sea weed) soup and sleep posture. 1) I studied 1,371 newborn infants who were born in th busan Maternity baby health center and 1,521 newborn infants in the Daegu maternity baby health center from June 1,1976 to may 31,1977. In Busan group, average weight of male newborn was 3.45kg, headgirth34.31cm, head length 11.68cm, head width 9.57cm. and cephalic index 82.02. Average weight of female newborn was 3.34kg, head girth 33.79cm, head length11.54cm, head width 9.44cm. and cephalic index 81.96. In Daegu group, average weight of male newborn was 3.28kg, head girth 34.65cm,head length 11.85cm, head width 9.50cm. and cephalic index 80.31. Average weight of female newborn was 3.18kg., head girth 34.08cm., headlength11.62cm., head width 9.38cm. and cephalic index 80.81. There was statistically significant difference in each item (p<0.01) 2) It was also studied in the order of delivery in the family. In Busan group, first baby was 43.5%, second baby 38.8% and sum of first and second baby was 82.3%. In Daegu group, first baby was 47.2%, second baby was 30.3% and sum of first and second baby was 77.5%. 3) I studied 1,686 male and 1,175 female from one to twelve month olds who visited my clinic for check up and vaccination from January 1,1976 to March 31,1978. Head girth, head length and head width were measured 3,660 times for male and 2,607 times for female. 4) Feeding was divided into breast feeding, Mixed feeding and artificial feeding. Period of maternal ingestion of sea weed soup were one, two, three and four weeks. Sleep postures were supine, lateral and prone position. Occipital protuberance that is not in the middline was divided into right or left occipital protuberance. 5) There were neither significant differences in head girth, head length, head width and cephalic index between breast, mixed and artificial feeding nor period of maternal ingestion of seaweed soup. 6) There was either significant difference in the cephalic index between supine and lateral position or supine and prone position. 7) Among 2,861 infants, breast feeding was 75.0%, mixed feeding 15.1% and artificial feeding 9.9%. Occipital protuberance that is not in the midline was 59.3%, left occipital protuberance 27.1% and right occipital protuberance 32.2%. 8) Occipital protuberance that is not in the midline was 70.5% in the supine position, 24.6% in the lateral position and 0.0% in the prone position. There were significant differences among them. 9) Period of maternal ingestion of seaweed soup were one week 10.4%, two weeks 28.0%, three weeks 33.0% and four weeks 28.6%.
Adult ; Breast ; Breast Feeding ; Busan ; Daegu ; Eating ; Female ; Head ; Humans ; Infant* ; Infant, Newborn ; Male ; Nutritional Support ; Posture ; Prone Position ; Seaweed ; Skull* ; Supine Position ; Undaria ; Vaccination

OBJECTIVE: To compare the safety and efficacy of prone and modified recumbent positions on minimal invasive percutaneous nephrolithotomy. METHODS: A total of 62 patients with upper urinary calculi were grouped into two groups, one of which consisted of 27 patients who underwent the minimal invasive percutaneous nephrolithotomy with modified recumbent position, and the other 35 patients with prone position. There was no significant statistical difference in the age, gender and complications between the two groups before surgery (P>0.05). Duration of and blood loss during surgery, complications in the perioperative period, and the length of postoperative hospital stay were all recorded. The data were analyzed by SPSS 13.0. RESULTS: Surgery was successful in all cases. There was no failure to puncture nor need to resort to open surgery. Average operation duration for the modified recumbent position group was (85.1± 25.3) min vs (97.2±30.6) min for the prone position group. Mean blood loss during the operation was (117.5± 49.7) mL vs (149.3±53.1) mL. There were no severe complications during and after surgery in the modified recumbent position group. In the prone position group, s one patient suffered pneumothorax during the operation and two suffered selective renal artery embolization because of massive hemorrhaging following the operation. There were significant differences in blood loss during surgery, in complications during the perioperative period, and in length of postoperative stay in hospital (P<0.05) between the two groups. CONCLUSION The patients are safer and more easily tolerate the minimal invasive percutaneous nephrolithotomy in the modified recumbent position than in the prone position, though the treatment efficacy of these two kinds of operation is similar. It is recommended that the modified recumbent position should be used generally in the percutaneous nephrolithotomy.
Adult ; Aged ; Female ; Humans ; Kidney Calculi ; surgery ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures ; methods ; Nephrostomy, Percutaneous ; methods ; Posture ; Prone Position ; Supine Position ; Ureteral Calculi ; surgery

STATEMENT OF PROBLEM: Proper proximal contact is important for maintaining and stabilizing the dental arch. However, the proximal contact strength (PCS) is not a constant value and can be affected by a variety of factors. PURPOSE: This study examined the influences of postural changes on the posterior PCS. MATERIAL AND METHODS: Twelve adults with a normal occlusion and had not undergone prosthetic treatment or proximal restoration were participated in this study. A metal strip was inserted into the proximal surface and removed at a constant velocity. The contact strength was measured in every contact point between canine to second molar in both arches. The PCSs were obtained initially in the upright position, secondly in the supine position and finally in the upright position again. All measurements were repeated after a 2 hour period. Statistical analysis was carried out using the Friedman test (P < .05). RESULTS: Generally, a decrease in PCS occurred when the posture was changed from the initial upright to supine position, while it increased when the posture was changed from the supine to upright position. A significant change was observed in all areas except for between the canine-first premolar in the maxilla and between the first molarsecond molar in the mandible areas. CONCLUSION: The posterior PCS, which dentists generally believe to be a static feature of occlusion, is affected significantly by posture.
Adult ; Bicuspid ; Dental Arch ; Dentists ; Humans ; Mandible ; Maxilla ; Molar ; Posture ; Supine Position

OBJECTIVE: The cardiovascular system maintains homeostasis through a series of adaptive responses to physiological requirements. However, little is known about the adaptation of fetal cardiac function to gravity, according to gestational age. In the present study, we aimed to evaluate the adaptive responses of cardiac function to postural changes, using Tei index measurements. METHODS: Fetal echocardiography and Doppler examination were performed on 114 women with vertex singleton pregnancies at 19 to 40 weeks' gestation. Participants were placed in an upright seated position, and the Tei index for fetal left ventricular cardiac function was measured. The women were then moved into a supine position and the Tei index was re-measured. RESULTS: The mean Tei index when measured in an upright seated position was significantly lower than that measured in a supine positioning for all fetuses (0.528±0.103 vs. 0.555±0.106, P=0.014, respectively). This difference was also noted in fetuses with a gestational age of 28–40 weeks (0.539±0.107 vs. 0.574±0.102, P=0.011, respectively). However, there was no difference in the Tei index between an upright seated and a supine position among fetuses with a gestational age of <28 weeks (0.505±0.091 vs. 0.516±0.103, P=0.571, respectively). CONCLUSION: Postural changes from an upright seated to a supine position result in an increased Tei index after a gestational age of 28 weeks. This appears to reflect maturation in the adaptive responses of the fetal cardiovascular system to postural changes.
Cardiovascular System ; Echocardiography ; Female ; Fetus ; Gestational Age* ; Gravitation ; Homeostasis ; Humans ; Posture ; Pregnancy ; Supine Position

PURPOSE: To investigate the change in intraocular pressure (IOP) of normal healthy eyes at different positions while performing sit-ups. METHODS: Twenty normal healthy eyes of 20 subjects were studied. IOP was measured while in the 'sitting upright', 'supine', and 'head-down' position to determine postural effect on IOP when executing a sit-up. Measurements were taken after the performance of a sit-up and during the performance of a sit-up, in both the head up and head down positions to test the effect of the exercise on the IOP. In addition, the IOP after an 'isometric exercise with Valsalva's maneuver in the supine or head-down position' was measured to determine the actual IOP during a sit-up. RESULTS: The postural change from sitting upright to tilting the head in a downward position caused the IOP to increase. After the performance of a sit-up, the IOP decreased in both the upright and supine positions, though IOP increased in the head-down position. After the isometric exercise with Valsalva's maneuver, IOP increased significantly regardless of position. CONCLUSIONS: IOP increased significantly during sit-ups, but decreased afterward. Future studies should be performed to evaluate the long-term effects of IOP change during and after sit-ups with respect to the prognosis of glaucoma.
Exercise ; Eye ; Glaucoma ; Head ; Intraocular Pressure ; Posture ; Prognosis ; Supine Position ; Valsalva Maneuver