Biomedical subjects

Yiong-Huak Chan

Publications and source records attributed to Yiong-Huak Chan.

At least 19 recordsLinked to original sources

PubMed2007

Simple antenatal preparation to improve breastfeeding practice: a randomized controlled trial.

OBJECTIVE: To address the impact of simple antenatal educational interventions on breastfeeding practice. METHODS: A randomized controlled trial was carried out in a tertiary referral center from May 2002 to December 2004. A random sample of eligible low-risk antenatal patients was recruited from clinics in the National University Hospital, Singapore. Group A received breastfeeding educational material and individual coaching from a lactation counselor. Group B received breastfeeding educational material with no counseling. Group C received routine antenatal care only. RESULTS: A total of 401 women were recruited. Mothers receiving individual counseling and educational material practiced exclusive and predominant breastfeeding more often than mothers receiving routine care alone at 3 months (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.2-5.4) and 6 months (OR 2.4, 95% CI 1.0-5.7) postpartum. More mothers practiced exclusive and predominant breastfeeding at 6 months among women receiving individual counseling compared with women exposed to educational material alone (OR 2.5, 95% CI 1.0-6.3). CONCLUSION: Where breastfeeding practices are suboptimal, simple one-encounter antenatal education and counseling significantly improve breastfeeding practice up to 3 months after delivery. Provision of printed or audiovisual educational material is not enough. Health care workers should make every effort to have one face-to-face encounter to discuss breastfeeding with expectant mothers before they deliver. CLINICAL TRIAL REGISTRATION: (www.ClinicalTrials.gov), NCT002770192 LEVEL OF EVIDENCE: I.

Breast Feeding↗

PubMed2006

Comparison of the scanning peripheral anterior chamber depth analyzer and the modified van Herick grading system in the assessment of angle closure.

PURPOSE: To compare the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and the modified van Herick grading system in the assessment of angle closure, using gonioscopy as the reference standard. DESIGN: Prospective comparative study. PARTICIPANTS: One hundred twenty phakic subjects (53 with primary angle closure and 67 with open angles) with no history of laser or intraocular surgery. METHODS: The modified van Herick grading system was used to grade the peripheral anterior chamber depth (ACD) clinically. The SPAC was used to assess ACD, and this was graded categorically as S (suspect angle closure), P (potential angle closure), or N (normal) and numerically from 1 to 12. One randomly selected eye of each subject underwent examination with the modified van Herick grading, SPAC, Goldmann applanation tonometry, optic disc examination, and gonioscopy. The SPAC measurements, modified van Herick grades (0%, 5%, 15%, 25%, 40%, 75%, and > or =100% of corneal thickness), and gonioscopy (graded as narrow or open) were correlated using the Spearman correlation coefficient. The receiver operating characteristics of the 2 methods to detect angle closure also were compared. MAIN OUTCOME MEASURES: Grading of ACD by the SPAC, the modified van Herick system, and gonioscopic grading of the angle. RESULTS: The SPAC results correlated well with the modified van Herick grading system (categorical grade, r = 0.527; numerical grade, r = 0.542; P<0.0001). For eyes graded as having narrow angles by gonioscopy, the area under the curve (AUC) for SPAC categorical grade S or P was 0.790; sensitivity and specificity were 84.9% and 73.1%, respectively. For the modified van Herick grading system, using a cutoff of peripheral ACD < or = 25% corneal thickness, the AUC was 0.872 and sensitivity and specificity were 84.9% and 89.6%. Compared with gonioscopy that found 53 of 120 cases of narrow angles, the SPAC graded more eyes as having narrow angles (63/120) than the modified van Herick system (52/120). CONCLUSIONS: The SPAC correlated well with the modified van Herick system in grading peripheral ACD. However, the SPAC appeared to overestimate the proportion of eyes with narrow angles relative to gonioscopy and the modified van Herick grading system.

Adult↗

PubMed2006

The 6-minute walk test predicts clinical outcome in Asian patients with chronic congestive heart failure on contemporary medical therapy: a study of the multiracial population in Singapore.

BACKGROUND: We sought the value of the 6-min walk test (6MWT) in predicting morbidity and mortality in Asian patients with congestive heart failure (CHF). METHODS: 668 patients (Age 66+/-12 years, Ejection fraction 29+/-13%, NYHA I to IV) were prospectively followed up for 36+/-12 months. 386 patients (58%) took the 6MWT. Cardiac events, defined as the composite end-point of death or CHF readmission were documented. RESULTS: 188 patients (28%) reached the composite end-point (63 deaths, 125 readmissions). 6MWT distance was an independent predictor of cardiac events (quartile 1 vs quartile 4)(p=0.041), as were beta-blocker or spironolactone use (p=0.008 for both), diabetes (p=0.042), monthly income less than SGD$1000 (p=0.030), and NYHA class (class III vs class I)(p=0.003). A 6MWT distance <340 m predicted occurrence of cardiac events with a sensitivity of 69% and specificity of 48%. CONCLUSIONS: The 6MWT is a safe and simple clinical tool, which could predict both morbidity and mortality in a large population of Asian patients with CHF of differing etiology and severity (169 words).

Age Factors↗

PubMed2006

Atropine for the treatment of childhood myopia.

PURPOSE: To evaluate the efficacy and safety of topical atropine, a nonselective muscarinic antagonist, in slowing the progression of myopia and ocular axial elongation in Asian children. DESIGN: Parallel-group, placebo-controlled, randomized, double-masked study. PARTICIPANTS: Four hundred children aged 6 to 12 years with refractive error of spherical equivalent -1.00 to -6.00 diopters (D) and astigmatism of -1.50 D or less. INTERVENTION: Participants were assigned with equal probability to receive either 1% atropine or vehicle eye drops once nightly for 2 years. Only 1 eye of each subject was chosen through randomization for treatment. MAIN OUTCOME MEASURES: The main efficacy outcome measures were change in spherical equivalent refraction as measured by cycloplegic autorefraction and change in ocular axial length as measured by ultrasonography. The primary safety outcome measure was the occurrence of adverse events. RESULTS: Three hundred forty-six (86.5%) children completed the 2-year study. After 2 years, the mean progression of myopia and of axial elongation in the placebo-treated control eyes was -1.20+/-0.69 D and 0.38+/-0.38 mm, respectively. In the atropine-treated eyes, myopia progression was only -0.28+/-0.92 D, whereas the axial length remained essentially unchanged compared with baseline (-0.02+/-0.35 mm). The differences in myopia progression and axial elongation between the 2 groups were -0.92 D (95% confidence interval, -1.10 to -0.77 D; P<0.001) and 0.40 mm (95% confidence interval, 0.35-0.45 mm; P<0.001), respectively. No serious adverse events related to atropine were reported. CONCLUSIONS: Topical atropine was well tolerated and effective in slowing the progression of low and moderate myopia and ocular axial elongation in Asian children.

Administration, Topical↗

PubMed2006

Changes in the optic disc after acute primary angle closure.

PURPOSE: To evaluate the changes in optic disc morphology in the first 4 months after an episode of acute primary angle closure (APAC) using stereoscopic optic disc photography and computer-assisted planimetry. DESIGN: Prospective observational case series. PARTICIPANTS: Forty-seven Asian subjects with unilateral APAC who were successfully treated with laser peripheral iridotomy (LPI). MAIN OUTCOME MEASURES: Cup-to-disc ratio (CDR) and optic cup and neuroretinal rim areas. METHODS: Stereoscopic optic disc photographs were taken 2 and 16 weeks after LPI, and the images were analyzed by computer-assisted planimetry. The overall, quadrantic, and 30 degrees sector areas of the optic disc, CDR, and neuroretinal rim area were analyzed by 2 independent masked graders, and the mean of the readings was used to calculate changes in optic disc parameters. RESULTS: The majority of the subjects were female (66%) and Chinese (90%), and the mean age was 67.6+/-11.2 years (range, 40-94). In APAC eyes from week 2 to week 16, the mean CDR increased from 0.56+/-0.05 to 0.59+/-0.03 (P<0.001), and the mean neuroretinal rim area decreased from 1.74+/-0.31 mm2 to 1.59+/-0.27 mm2 (P<0.001). Quadrantic and sector analysis showed preferential loss of neuroretinal rim area at the superotemporal and inferotemporal areas. There was no significant change in optic disc parameters in the fellow eyes over the study period. CONCLUSIONS: This study demonstrated changes in optic disc morphology from week 2 to week 16 after an episode of APAC. The pattern of optic nerve damage demonstrated in our study was comparable with that seen in primary open-angle glaucoma and experimental glaucoma models.

Acute Disease↗

PubMed2006

Lens opacity, thickness, and position in subjects with acute primary angle closure.

PURPOSE: To compare lens thickness (LT), lens position (LP), relative lens position (RLP), and degree and type of lens opacity between affected and fellow eyes of subjects with acute primary angle closure (APAC) to identify any differences in lens characteristics that may be contributory to the acute episode. In addition, axial length (AL) and anterior chamber depth (ACD) measurements were evaluated. METHODS: Seventy-three study subjects with unilateral APAC were treated with sequential laser iridotomy (LI) in both eyes. Two weeks after LI, ACD, LT, and AL measurements were made in both eyes using ultrasound pachymetry. LP was defined as ACD+1/2LT and RLP as LP/AL. The Lens Opacity Classification III (LOCS III) System was used for grading lens opacity. RESULTS: The subjects were 90% Chinese and 63% female. Mean age was 61.0+/-10.9 years. Significant differences between the affected and fellow eyes were found in the ACD (2.11+/-0.35 vs 2.18+/-0.23; P=0.02) and LP (4.61+/-0.47 vs 4.75+/-0.29; P=0.02). Cortical opacity was greater in fellow eyes (0.32+/-0.72 vs 0.53+/-0.95; P=0.02). There was no difference in LT, RLP, or degree of lens opacity in the nuclear and posterior subcapsular regions. CONCLUSIONS: Compared with fellow eyes, APAC-affected eyes have shallower ACD, more anterior LP, and less cortical opacity. These differences may be contributory to APAC.

Acute Disease↗

PubMed2006

Opposing trends in incidence of esophageal squamous cell carcinoma and adenocarcinoma in a multi-ethnic Asian country.

OBJECTIVES: To describe the incidence trends in esophageal squamous cell carcinoma (SCC) and adenocarcinoma among the three major ethnic groups in Singapore from 1968 to 2002. METHODS: Esophageal cancer cases in Singapore citizens and permanent residents obtained from the Singapore Cancer Registry and population data derived from the national census were used to calculate the incidence rates from 1968 to 2002. RESULTS: The age-standardized incidence rates (ASRs) for SCC decreased progressively from 8.31 to 3.85 per 100,000 men (p = 0.017) and from 3.43 to 0.81 per 100,000 women (p = 0.027). The rates fell for all three ethnic groups. The ASR for adenocarcinoma rose from 0 to 0.54 per 100,000 men and from 0.03 to 0.13 per 100,000 women, although these time trends did not achieve statistical significance. The frequency of regular smoking in the population decreased from 23% in 1966/1977 to 12.6% in 2004. The percentage of obesity in adults rose from 4.3% in 1982-1985 to 6.9% in 2004. The frequency of esophagitis in Singapore based on endoscopic findings increased from 3.9% in 1992 to 9.8% in 2001. CONCLUSIONS: The decline in the incidence of SCC is likely to be associated with the known decrease in the frequency of smoking among Singaporeans. In contrast, there appears to be a trend toward an increase in the incidence of adenocarcinoma in Singapore, although the absolute incidence remains relatively low. This may be due to the associated rise in the frequency of reflux esophagitis and obesity in Singapore.

Adenocarcinoma↗

PubMed2006

Longitudinal study of anisometropia in Singaporean school children.

PURPOSE: The purpose of this study was to document the incidence rates of anisometropia, year-by-year prevalences, changes in the intereye difference in spherical equivalent (SE), and its association with myopia progression and axial length changes in a cohort of Singaporean school children. METHODS: This is a prospective cohort study of Singaporean school children (n = 1979) aged 7 to 9 years who were examined annually with cycloplegic refraction and ultrasonography over a 3-year period. RESULTS: In the 1908 children without anisometropia at commencement, the 3-year cumulative incidence rate of anisometropia (difference in SE at least 1.0 D) was 144 (7.55%; 95% CI: 6.42-8.85). The mean intereye difference in SE in all children at baseline was 0.29 +/- 0.46 D (SD: 0.46) and increased to 0.44 D (0.59) on the last examination. On the initial examination, 3.6% (95% CI: 2.8-4.4) or 71 children had anisometropia. Of the 59 of 71 children who completed all examinations, only 3 (5.1%) had an increase in the intereye difference in SE by at least 0.5 D, whereas 2 (3.4%) had a decrease of at least 0.5D. The mean intereye difference in SE was stable between visits. The change in intereye difference in SE correlated with the change in intereye axial length (r = 0.43). Compared with the isometropic children, each eye of the anisometropic children had a higher rate of progression of myopia. CONCLUSIONS: The 3-year incidence of anisometropia was 7.55% in these young Singaporean children. Although the frequency of anisometropia increased with time, the difference in SE between eyes tended to remain stable.

Anisometropia↗

PubMed2006

A study on the knowledge, attitudes and practices of Southeast Asian dermatologists in the management of atopic dermatitis.

INTRODUCTION: This study evaluated the knowledge, attitudes and practices of Southeast Asian dermatologists in the management of atopic dermatitis (AD). MATERIALS AND METHODS: A questionnaire survey of 255 dermatologists in Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam. RESULTS: Familiarity with diagnostic criteria varied considerably. The usage of moisturisers by the respondents from Vietnam and Indonesia was significantly less frequent than the other countries. Most respondents (91% to 100%) used topical corticosteroids in children with mild-to-moderately severe dermatitis. Some respondents in the Philippines (17% to 19%) and Vietnam (11% to 25%) only used topical corticosteroids for severe disease. For infected eczema, most respondents would prescribe systemic antibiotics for mild-to-moderate infection. A minority in the Philippines (14%) and Vietnam (11%) did so only for severe infection. The top 4 systemic antibiotics prescribed most frequently were: erythromycin, cloxacillin, cephalosporin and amoxicillin/clavulanic acid. In Indonesia, a large proportion of the respondents (47%) prescribed amoxicillin most frequently. The majority of respondents (60% to 100%) prescribed both sedating and non-sedating oral antihistamines. Most respondents used oral corticosteroids to treat severe AD. Some in Malaysia, Singapore and Vietnam used cyclosporin (7% to 58%), azathioprine (5% to 31%) and methotrexate (5% to 14%). With the exception of those in Singapore, the majority of respondents (71% to 97%) did not use phototherapy. CONCLUSION: Familiarity with diagnostic criteria, the early and judicious use of moisturisers and topical corticosteroids, as well as the treatment of Staphylococcus aureus superinfection with penicillinase-stable antibiotics should be emphasised in this region.

Anti-Bacterial Agents↗

PubMed2005

Configuration of the drainage angle, intraocular pressure, and optic disc cupping in subjects with chronic angle-closure glaucoma.

OBJECTIVE: To investigate the relationship between drainage angle configuration with untreated intraocular pressure (IOP) and optic disc cupping in subjects with chronic angle-closure glaucoma (CACG). DESIGN: Prospective, observational study. PARTICIPANTS: Two hundred seventy-five Asian subjects with CACG who participated in a randomized controlled trial that investigated the IOP-reducing effect of latanoprost and timolol. METHODS: Chronic angle-closure glaucoma was defined as the presence of glaucomatous optic neuropathy (with or without a visual field defect), an anterior chamber angle in which the pigmented trabecular meshwork was not visible for at least 180 degrees on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in association with elevated IOP of 21 mmHg or more. Static and dynamic gonioscopy were performed, the angles were graded in each quadrant according to the Shaffer scheme, and the number of clock hours of PAS was recorded. The untreated IOP and vertical cup-to-disc ratio were correlated with mean angle width and extent of PAS. MAIN OUTCOME MEASURES: Mean angle width, clock hours of PAS, IOP, and vertical cup-to-disc ratio. RESULTS: Most subjects were female (75%), and the mean age was 62.9+/-9.4 years. The mean angle width was 0.77+/-0.53 and the mean number of clock hours of PAS was 4.77+/-3.2 hours. Untreated IOP correlated with angle width (r = -0.23; P<0.001) and clock hours of PAS (r = 0.22; P<0.001). Vertical cup-to-disc ratio also correlated with angle width (r = -0.17; P = 0.004) and PAS (r = 0.28; P<0.001). Performing a multiple linear regression using baseline IOP as the outcome variable with age, gender, clock hours of PAS, and angle width as predictors, there was a 0.39-mmHg (95% confidence interval, 0.15-0.63) increase in baseline untreated IOP for each unit increase in clock hours of PAS (P = 0.002). CONCLUSIONS: In subjects with CACG, the extent of PAS and a narrower width of the drainage angle were associated with higher untreated IOP and a larger vertical cup-to-disc ratio.

Adult↗

PubMed2005

Degree of angle closure and the intraocular pressure-lowering effect of latanoprost in subjects with chronic angle-closure glaucoma.

OBJECTIVE: To examine the relationship between the configuration of the drainage angle and intraocular pressure (IOP)-lowering efficacy of latanoprost in subjects with chronic angle-closure glaucoma (CACG). DESIGN: Prospective observational case series. PARTICIPANTS: One hundred thirty-seven Asian subjects with CACG. METHODS: Study subjects had participated in a 12-week, randomized, double-masked study that assessed the IOP-reducing effect of latanoprost. Chronic angle-closure glaucoma was defined as optic neuropathy with or without a visual field defect, an anterior chamber angle in which the trabecular meshwork was not visible for at least 180 degrees on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in association with a chronically elevated IOP. Static and dynamic gonioscopy was performed at baseline. The angles were graded in each quadrant according to the Shaffer scheme, and the number of clock hours of PAS was recorded. The change in daily IOP (defined as the mean of the 9:00 am and 5:00 pm IOP time point values) from baseline to week 12 was analyzed and correlated with mean angle width and extent of PAS. RESULTS: One hundred thirty-seven Asian subjects with CACG completed the study in the latanoprost-treated group. Most subjects were female (75%), and the mean age was 62.6+/-9.4 years. At baseline, the mean angle width was 0.84+/-0.55, and the mean number of clock hours of PAS was 4.67+/-2.95. After 12 weeks of treatment, latanoprost reduced IOP from 25.0+/-5.5 mmHg to 17.5+/-5.0 mmHg (P<0.001). The percent change in IOP produced by latanoprost was not associated with mean angle width (Spearman's r = 0.04, P = 0.64) or the number of clock hours of PAS (Spearman's r = -0.15, P = 0.08). CONCLUSIONS: In subjects with CACG, the IOP-reducing efficacy of latanoprost was not affected by the degree of angle narrowing or extent of synechial angle closure.

Adult↗

PubMed2005

Iris ischaemic changes and visual outcome after acute primary angle closure.

BACKGROUND: Ischaemic changes in the iris occur frequently after an episode of acute primary angle closure (APAC). The aim of this study was to investigate the significance of such changes with regards to visual outcome. METHODS: Acute primary angle closure cases were treated with medical therapy followed by laser peripheral iridotomy after resolution of the acute episode. Subjects were examined at 1, 4, 8, 12 and 16 weeks post laser peripheral iridotomy. Eyes were examined for signs of iris ischaemic changes (IIC), defined as the presence of iris whorling or stromal atrophy. Iris photographs were also taken at weeks 1, 8 and 16. Subjects requiring glaucoma medication or filtering surgery during the follow-up period were excluded. The visual acuity and visual field (using automated white-on-white threshold perimetry) at week 16 were used in the assessment of visual outcome. RESULTS: Sixty-one subjects with APAC completed the study. The majority of subjects were female (82%) and Chinese (92%), and the mean age was 59 +/- 8.8 years. More than half the subjects (52.5%) were found to have developed IIC during the study, 65% of whom already had signs of IIC by the first week. Only 13 subjects (41%) with IIC and 6 subjects (21%) without IIC had an abnormal visual field defect at week 16 (P = 0.09). There was also no difference in visual acuity at week 16, the majority of subjects in both groups having visual acuity of 6/12 or better. CONCLUSIONS: The development of iris ischaemic changes after a single episode of APAC may not be associated with an adverse visual outcome.

Acute Disease↗

PubMed2005

Increasing trend of reflux esophagitis and decreasing trend of Helicobacter pylori infection in patients from a multiethnic Asian country.

OBJECTIVES: This study aimed to determine time trends in the frequency of endoscopic esophagitis, and Helicobacter pylori (H. pylori) infection in a large Singaporean teaching hospital over a 10-yr period. METHODS: We studied a consecutive series of 16,375 patients who had been newly referred for diagnostic esophagogastroduodenoscopy from 1992 to 2001. All endoscopic findings were prospectively recorded. From 1995, an antral biopsy was taken from 6,185 unselected patients for an in-house biopsy urease test. Endoscopic esophagitis was defined as the presence of erosions and/or ulceration. The relationship between erosive esophagitis and various relevant factors was analyzed. RESULTS: The overall prevalence of endoscopic esophagitis was 6.9% (95% CI, 6.5-7.3). It was 7.3% (95% CI, 6.2-8.4) in patients with a positive urease test, and 9.0% (95% CI, 8.1-9.9) in those in whom the urease test was negative (p < 0.001). From 1992 to 2001, the frequency of endoscopic esophagitis increased (p < 0.001 for trend) while that of positive urease test decreased from 1995 to 2001 (p < 0.001 for trend). The increase in the prevalence of endoscopic esophagitis (RR 1.99, 95% CI 1.18-3.36, p= 0.0098), and its inverse relationship with positive urease test results (RR 0.991, 95% CI 0.983-0.999, p= 0.049) remained significant even after adjusting for age, gender, ethnic distribution, and hiatal hernia. CONCLUSIONS: The frequency of endoscopic esophagitis increased in Singapore from 1992 to 2001. This increase within a short period of time suggests that environmental factors, of which the decreasing rate of H. pylori infection may be one, are important in the pathogenesis of gastroesophageal reflux disease.

Breath Tests↗

PubMed2004

Pruritus, pain, and small nerve fiber function in keloids: a controlled study.

BACKGROUND: Keloid scars can itch and hurt, but little is known about the characteristics of these symptoms in keloids. Because itch and pain are carried by small nerve fibers, abnormal function of these fibers could be an explanation for such phenomena. OBJECTIVE: We sought to assess the characteristics of itch and pain in keloid scars, and to assess the function of small nerve fibers in keloids. METHODS: We studied the location and intensity of itch and pain in keloids that had been present for at least 1 year. We further studied the function of small nerve fibers by assessing allodynia and alloknesis (which are pain and itch, respectively) from innocuous stimuli that do not normally provoke pain and itch, and we used quantitative thermosensory testing (in keloid lesions, perikeloidal skin, and contralateral normal skin as a control). Results In all, 28 patients (13 men and 15 women) with a mean age of 34 years were enrolled and completed the study. Of the patients, 86% experienced itch and 46% experienced keloid-related pain. Of those who experienced itch, 92% felt the itch at the edge of their keloids. Of the patients with pain, 77% felt pain at the center of the keloid. Mechanical allodynia was noted in 43% of the patients, and only 14% experienced alloknesis. Abnormal thermosensory thresholds to warmth, cold, and heat pain were noted in the keloids. Visual analogue scale of itch correlated significantly to warmth ( r = 0.65), heat pain ( r = 0.4), and cold pain ( r = -0.41). CONCLUSION: Itch and pain are common presentations in keloids and are associated with abnormalities in small nerve fiber function, suggesting a small nerve fiber neuropathy.

Adult↗

PubMed2004

Changes in retinal nerve fiber layer thickness after acute primary angle closure.

PURPOSE: To evaluate the changes in retinal nerve fiber layer (RNFL) thickness in the first 16 weeks after acute primary angle closure (APAC) using scanning laser polarimetry (SLP). DESIGN: Prospective, observational case series. PARTICIPANTS: Thirty-seven Asian subjects with APAC. METHODS: For all cases, APAC had resolved after treatment, and the study was conducted during the follow-up period after the acute episode. Using the GDx Nerve Fiber Analyzer (Laser Diagnostic Technologies, San Diego, CA), the RNFL was assessed in both eyes 2 weeks after APAC, and again after 16 weeks. The SLP parameters were compared between week 2 and week 16 within affected and fellow eyes. A multiple logistic regression analysis was carried out to analyze factors likely to influence RNFL outcome. MAIN OUTCOME MEASURES: Superior and inferior average RNFL thickness. RESULTS: The mean age of study subjects was 60.1+/-10.3 years (range, 46-91 years), and most subjects were female (68%) and Chinese (86%). In APAC eyes, the superior average RNFL thickness decreased from 63.8+/-13.6 microm to 61.4+/-11.2 microm (P = 0.04) and the inferior average RNFL thickness decreased from 69.5+/-14.4 microm to 66.3+/-12.6 microm (P = 0.005). There was also a decrease in inferior ratio (P = 0.008) and ellipse modulation (P = 0.02). In the fellow eyes, there was no difference found between week 2 and week 16 for any of the SLP parameters studied. Logistic regression analysis showed no significant association between developing a 10% reduction in either superior or inferior RNFL thickness with age, gender, history of ischemic risk factors, duration of symptoms during APAC, the level of presenting intraocular pressure (IOP), or the development of a rise in IOP between study visits. CONCLUSIONS: After an episode of APAC, superior and inferior average RNFL thickness was found to decrease significantly from week 2 to week 16.

Acute Disease↗

PubMed2004

Psychosocial stressors that precipitate dissociative trance disorder in Singapore.

OBJECTIVE: To study the psychosocial stressors that precipitate dissociative trance disorder (DTD) and to identify predictors of DTD. METHOD: We conducted semistructured interviews in which detailed information was obtained for 58 cases diagnosed with DTD at a psychiatric hospital in Singapore. A comparison group of 58 patients who received treatment at the same hospital for major depression (MD) were also interviewed, using the same instrument. RESULTS: While 100% of the DTD group described at least one psychosocial stressor, only 80% of the MD group did so. Common stressors for the DTD group include problems with military life (38%), conflicts over religious and cultural issues (38%), and domestic disharmony and marital woes (24%). Conflicts over religious and cultural issues seemed to be important in the precipitation of DTD but not in the precipitation of MD (p < 0.001). Logistic regression reveals that the following are positive predictors for DTD: conflicts over religious and cultural issues; prior exposure to trance states; and being a spiritual healer or his/her assistant. CONCLUSIONS: An understanding of the precipitating psychosocial stressors that overwhelmed the patient's coping abilities would have implications for treatment and enable the clinician to devise strategies for intervention and prevention.

Adolescent↗

PubMed2004

Variability of somatosensory evoked potential monitoring during scoliosis surgery.

OBJECTIVE: Somatosensory evoked potentials (SEPs) of 65 patients undergoing scoliosis surgery were monitored by stimulation of posterior tibial nerve to observe variations in latencies and amplitudes. METHODS: Monitoring was divided into five stages: pre incision, spine exposure, instrumentation loading, deformity correction, and wound closure (stages 1-5, respectively). RESULTS: We found the latency showed significant increase and the amplitude significant reduction from stages 1 to 2. There was no significant variability from stages 2, 3, and 4, but both latency and amplitude recovered significantly from stage 4 to 5. This variability correlated with the changes in mean arterial pressure and end-tidal concentrations of isoflurane and was not dependent on the type of surgical procedure. If either 50% amplitude reduction or 10% latency prolongation of SEP compared with baseline recordings at stage 1 (pre incision) was used as warning criterion, the overall false-positive rate was 23.1%. It was significantly reduced to 7.7% if stage 2 (spine exposure) recordings were used as the baseline (P < 0.05). The false-positive rate decreased to 0% if a combined 50% amplitude reduction and 10% latency prolongation of SEP compared with the stage 2 baseline were used (P < 0.001). CONCLUSION: Based on these findings, we concluded that the time to obtain SEP baseline data should be adjusted to be post incision instead of pre incision.

Adolescent↗

PubMed2004

Barrier repair in chronic plaque-type psoriasis.

PURPOSE: To investigate barrier repair after mild trauma in lesional skin of psoriasis patients with chronic plaque-type disease and to compare this with non-involved psoriatic skin and normal controls. METHODS: Transepidermal water loss (TEWL) readings were taken from involved psoriatic skin and non-involved skin of psoriasis patients as well as the skin of normal controls. Three readings were performed at each site: the basal state, immediately after 20 tape strippings and 1 week post stripping. RESULTS: Higher baseline, post-stripping and 1-week recovery TEWL readings in psoriatic-involved skin compared to non-involved and normal control skin. No significant difference in barrier recovery rate in psoriatic-involved skin compared to non-involved and normal control. CONCLUSION: Although there appears to be a derangement of barrier function in lesional skin of psoriasis patients compared to non-lesional skin and the skin of healthy controls, the barrier recovery function of lesional psoriatic skin is still fully operational.

Body Water↗