Does knowledge and attitude of healthcare professionals working in critical care areas affect their willingness to offer the option of organ donation? results of a tertiary hospital survey.

INTRODUCTION: Organ donation (OD) rates in Malaysia have remained suboptimal for decades. Healthcare professionals (HCPs) working in critical care areas are responsible for diagnosing brain death (BD) and initiating the OD process. Impact of their knowledge and attitudes on willingness to offer the option of OD to families of potential donors is unknown. METHODS: Knowledge and attitudes about BD, OD, and organ transplantation (OT) of critical care HCPs in a Malaysian transplant centre were studied using a validated questionnaire. Responses were analysed using multivariable analysis with willingness to offer the option of OD to families of potential donors as dependent variable. RESULTS: Age (p = 0.04), profession (doctors > nurses, p < 0.001), religion (Buddhists > others, p = 0.013) [but not ethnicity], higher knowledge scores for Brain Death Test, Brain Death Knowledge, Organ Donation and Transplantation, and overall knowledge score (p < 0.001) were associated with greater odds of offering OD to families. Belief in the reliable diagnosis of BD, confidence in explaining BD, and belief that OD will not affect religious services were significantly associated with willingness to offer OD, while HCPs who were willing to personally donate organs had greatest odds (p < 0.001). Other factors that significantly influenced HCPs' willingness to offer included their perception about families' willingness to donate, body disfigurement, and confidence in OT. CONCLUSIONS: Overall, HCPs had highly positive attitudes. However, potential barriers in offering OD to families were identified. Proven interventions from international experience could help address these issues and likely improve OD rates in Malaysia.

Investigation of chemical partitioning of 7Be, 210Pb and 137Cs and novel dating of road sediment by 210Po:210Pb disequilibrium method.

A suite of road sediment and soil samples from a post-industrial city (Detroit, MI) were collected and analyzed for atmospherically-delivered 210Pb, 210Po, 7Be along with 226Ra and 137Cs in the bulk and size-fractionated solid samples. From the measured atmospheric depositional fluxes of 7Be, 210Po, and 210Pb, the initial 210Po/210Pb activity ratio was quantified. In all samples, there is disequilibrium between 210Po and 210Pb, with a 210Po/210Pb activity ratio (AR) of <1.0, which is reported for the first time. Using the measured 210Po/210Pb AR, the average 'apparent age' of road sediment was found to be 146 ± 62 days. Using numerical modeling, it is predicted that the (210Po/210Pb) excess activity ratio will reach a 'dynamic equilibrium' value of ~0.59 over a period of >1 year. Results from a subset of samples that were sequentially extracted for exchangeable, carbonate, Fe-Mn oxide, organic and residual phases indicate the Fe-Mn oxide fraction was found to contain the largest fraction of 7Be and 210Pb; however, the largest fraction of 210Pb was associated with the residual phase and is attributed to complexation of 210Pb with recalcitrant organic matter. This study shows that the natural tagging of 7Be and 210Po-210Pb pair via precipitation provides insights on the time scale of their mobility and adds a new dimension of time information on the pollutant-laden road sediment.

Radioactive impact in South Korea from the damaged nuclear reactors in Fukushima: evidence of long and short range transport.

Traces of long-lived fallout-derived radioisotopes ((134)Cs and (137)Cs) were found in wet and dry deposition samples collected from the west and east coasts of South Korea from March to May 2011 following the release of radionuclides from the damaged nuclear power plants in Fukushima, Japan. The analysis of air mass back trajectory and atmospheric pressure systems indicated that the Fukushima-derived radiocaesium had predominantly reached South Korea from the west by surface westerlies from 11 March to 5 April; however, after 6 April, air masses arrived from Japan directly due to a high pressure system that developed to the east of Japan. Spatial variation of deposition fluxes of radiocaesium in South Korea was partly attributed to the presence of local longitudinal orography.

210Po concentration in different size fractions of aerosol likely contribution from industrial sources.

210Po, being a highly radiotoxic isotope, could contribute to significant inhalation dose to humans. This study establishes the first set of atmospheric 210Po data in aerosol samples collected across Kuwait. The primary focus of this study is to investigate spatio-temporal variability of atmospheric 210Po and assess its sources, including anthropogenic contributions. Measurements of 210Po in aerosols collected over a period of 23 months (January 2018-November 2019) from three different locations, i.e., a remote area (120 km) north of Kuwait City, Kuwait city and an industrial site (60 km from Kuwait City center). Specific activities of 210Po were determined in 3 different size fractions (0.39-2.5 µm, 2.5-10 µm and ≥10 µm) and the highest activity was observed in the fine fraction (PM0.39- 2.5) across all sampling stations during both the summer and winter seasons. The highest activities in all the size fractions were measured downwind of the Industrial site that houses oil refineries, cement factory and some other industries including a Power and Desalination Plant. In terms of temporal variations, higher summertime activities were observed across the spatial domain. Longer residence time of atmospheric 222Rn-produced 210Pb resulting in lower scavenging of atmospheric 210Pb, due to very little precipitation in summer, will result in higher atmospheric 210Po.

Clinical Evaluation of Placement of Implant by Flapless Technique Over Conventional Flap Technique.

AIM: The aim of this study was to compare the clinical advantages of flapless implant surgery over conventional flap technique of implant placement by assessing the marginal bone loss in 1 month, 2 months and 3 months postoperatively, pain assessment, number of analgesics taken by the patients postoperatively and the postoperative swelling between two groups. MATERIALS AND METHODS: This study was conducted at Department of Oral and Maxillofacial Surgery, Rajas Dental College and Hospital, Tirunelveli. The patients were assigned randomly to one of the two groups-flap (ten patients) or flapless (ten patients). Digital IOPARs were taken postoperatively. The parameters assessed were marginal bone loss (interproximal bone height), pain assessment by a 10-cm visual analog scale, swelling assessment by modification of tape measuring method by Gabka and Matsumara and the number of analgesics tablets taken every postoperative day from the day of surgery to 6 days after surgery. RESULTS AND STATISTICS: Descriptive statistics was done by calculating measures of central tendency (mean) and measures of dispersion (standard deviation) for all the parameters. Inferential statistics were done by unpaired Student's t test to compare the mean difference between the two groups. The results of this study showed that the mean difference in the bone loss for baseline to the third month for the flap group was 0.34 ± 0.05 and for the flapless group was 0.03 ± 0.004 (p = 0.000***). Pain assessment by visual analog scale was statistically significant in all the 5 postoperative days indicating a better patient compliance in the flapless group and there was no statistical difference in the level of swelling between these two groups. CONCLUSION: Within the limitations of this study, it can be concluded that flapless implant surgery results in lesser loss of marginal bone and also results in better patient comfort; however, proper patient selection and technique is essential for a successful flapless implant surgery.

Late glacial climate record of midwestern United States from the hydrogen isotope ratio of lake organic matter.

A hydrogen isotope time series obtained from an analysis of organic matter extracted from a lake core in Kalamazoo, southwestern Michigan, reveals four distinct isotope stages within the last 12,000 years that can be interpreted in terms of oscillations between cold and warm, dry climates. The most dramatic are a cold phase between 12,000 and 9000 years before present (B.P.), a warm, dry period between 8500 and 2000 years B.P., a cold period between 2000 and 1000 years B.P., and a warming trend since 1000 years B.P. The warming trend of the last 1000 years is comparable in magnitude to the mid-Holocene warm phase.

Prevalence of primary angle-closure disease in an urban south Indian population and comparison with a rural population. The Chennai Glaucoma Study.

OBJECTIVE: To determine the prevalence of primary angle-closure glaucoma (PACG), primary angle closure (PAC), and PAC suspect (PACS) in an urban population, and to compare prevalence and associated risk factors with a rural population. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Four thousand eight hundred subjects 40 years or older were selected from Chennai city using multistage random cluster sampling. INTERVENTION: All subjects had a complete ophthalmic examination that included logarithm of the minimum angle of resolution visual acuity, applanation tonometry, gonioscopy, grading of lens opacities, dilated fundus examination, optic disc photography, and visual fields. MAIN OUTCOME MEASURES: Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology classification. RESULTS: Three thousand eight hundred fifty (80.2%) responded; 34 subjects (17 female, 17 male) had PACG (0.88%; 95% confidence interval [CI], 0.60-1.16). The mean intraocular pressure (IOP) was 26.0+/-14.9 mmHg. Five subjects (14.7%) had been previously diagnosed to have glaucoma, 1 of whom had undergone glaucoma surgery and 2 of whom had been diagnosed to have open-angle glaucoma. Two subjects (5.9%) were bilaterally and 3 subjects (8.8%) were unilaterally blind. One hundred six subjects (2.75%; 95% CI, 2.01-3.49) were diagnosed to have PAC (62 female, 44 male). Thirty-nine subjects (36.8%) had presenting IOP > 24 mmHg, 83 (78.3%) had peripheral anterior synechiae, and 16 (15.1%) had both. Two hundred seventy-eight subjects (7.24%; 95% CI, 6.38-8.02) had PACS (183 female, 95 male). Prevalences of PACG and PACS were similar in the urban and rural populations. Primary angle closure prevalence was higher in the urban population (P<0.0001). Primary angle closure and PACG were positively associated with increasing age and IOP in both populations and were more common in rural women (odds ratio [OR], 4.3; 95% CI, 2.2-8.3). Association with hyperopia was seen only in the urban population (OR, 2.0; 95% CI, 1.4-2.8). CONCLUSIONS: Prevalences of PACG and PACS were similar in the rural and urban populations; PAC was more common in the urban population. In both groups, the disease was asymptomatic. Poor detection rates were probably due to lack of gonioscopy as a routine part of an eye examination.

Prevalence of primary open-angle glaucoma in an urban south Indian population and comparison with a rural population. The Chennai Glaucoma Study.

OBJECTIVE: To estimate the prevalence and risk factors of primary open-angle glaucoma (POAG) in an urban population and compare the same with that of our published rural population data in southern India. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Four thousand eight hundred subjects 40 years or older were selected using a multistage random cluster sampling procedure in Chennai city. INTERVENTION: Three thousand eight hundred fifty (80.2%) subjects underwent a complete ophthalmic examination, including applanation tonometry, gonioscopy, pachymetry, optic disc photography, and automated perimetry. MAIN OUTCOME MEASURES: Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology Classification. RESULTS: The distribution of intraocular pressure (IOP) and vertical cup-to-disc ratio (VCDR) was obtained from the right eye of the 2532 subjects with normal suprathreshold visual fields. Mean IOP was 16.17+/-3.74 mmHg (97.5th and 99.5th percentiles, 24 mmHg and 30 mmHg). The mean VCDR was 0.43+/-0.17 (97.5th and 99.5th percentiles, 0.7 and 0.8). One hundred thirty-five (64 men, 71 women) subjects had POAG (3.51%; 95% confidence interval [CI], 3.04-4.0). Primary open-angle glaucoma subjects (58.4+/-11.3 years) were older (P<0.0001) than the study population (54.8+/-10.6 years). One hundred twenty-seven (94%) subjects were diagnosed to have POAG for the first time. Two subjects (1.5%) were bilaterally blind, and 3 (3.3%) were unilaterally blind due to POAG. The urban population prevalence was more than that of the rural population (1.62%; 95% CI, 1.4%-1.8%; P<0.0001). In both populations, increasing IOP (per millimeter of mercury) and older age were associated with the disease. There was no association with gender, myopia, systemic hypertension, diabetes, or central corneal thickness. CONCLUSIONS: The prevalence of POAG in a > or =40-year-old south Indian urban population was 3.51%, higher than that of the rural population. The prevalence increased with age, and >90% were not aware of the disease.

Agreement between two Goldmann type applanation tonometers.

The aim of the study was to assess agreement between two commercially available applanation tonometers for the measurement of intraocular pressure (IOP). Forty subjects underwent IOP measurement on two accurately calibrated Goldmann type applanation tonometers (Zeiss AT 030 (GATZ) and Inami L-5110(GATI)). The order of examination was randomized and observers were masked to the IOP recorded. The mean of two consecutive readings, from a randomly selected eye for each subject, was used for analysis. Agreement was assessed using the Altman and Bland plot. The mean (SD) IOP readings on GATZ was 15.32 (+/-6.80) mm Hg and on GATI was 13.52 (+/-5.65) mm Hg (p< 0.001, 95% CI of the difference: -2.48 to -1.11). The 95% limits of agreement on the Altman and Bland plot were:-2.47 to 6.16 mm Hg). There was significant inter-instrument variability between the two accurately calibrated Goldmann type applanation tonometers studied.

A randomized, crossover, open label pilot study to evaluate the efficacy and safety of Xalatan in comparison with generic Latanoprost (Latoprost) in subjects with primary open angle glaucoma or ocular hypertension.

AIM: To compare the efficacy and tolerability of Xalatan with generic latanoprost (Latoprost) in subjects with primary open angle glaucoma (POAG) or ocular hypertension (OH). MATERIALS AND METHODS: This was a single-center, randomized, open label, crossover, two period comparative study. At the baseline visit, subjects were randomized to two groups. Group A received Xalatan for weeks 1-12 followed by Latoprost for weeks 13-24. Group B received Latoprost for weeks 1-12 followed by Xalatan for weeks 13-24. RESULTS: 30 subjects were recruited, 12 in Group A and 18 in Group B. In subjects administered Xalatan, intraocular pressure (IOP) showed a greater decrease (P < 0.001) from 23.64 +/- 3.13 mmHg at baseline to 14.29 +/- 1.61 mmHg at week 12 (fall of 9.35 +/- 3.55 mmHg, 38.66% +/- 10.29) than that seen in the Latoprost group (22.74 +/- 2.47 mmHg to 16.98 +/- 2.49 mmHg, fall of 5.76 +/- 1.41 mmHg; 25.42% +/- 5.98). In period 2 when subjects were crossed over to Xalatan from Latoprost, there was a further fall from 16.98 +/- 2.49 mmHg to 16.09 +/- 1.49 at week 24 (fall of 0.89 +/- 1.59 mmHg; 4.3% +/- 8.76). However, when subjects were crossed over to Latoprost from Xalatan, the IOP rose from 14.29 +/- 1.61 mmHg to 15.36 +/- 1.71 mmHg at week 24 (8.86% +/- 17.76). There was no significant difference in incidence of conjunctival hyperemia or any other adverse events in both the groups. CONCLUSION: The magnitude of IOP lowering in patients with POAG and OH with Xalatan and Latoprost is different. In our study, the IOP lowering with Xalatan was higher than that with Latoprost.

Inconsistencies between 14C and short-lived radionuclides-based sediment accumulation rates: Effects of long-term remineralization.

14C is the most widely utilized geochronometer to investigate geological, geochemical and geophysical problems over the past 5 decades. Establishment of precise sedimentation rates is crucial for the reconstruction of paleo-climate, -ecological and - environmental studies when extrapolation of sedimentation rates is utilized for time scales beyond the dating range. However, agreement between short-term and long-term sedimentation rates in anthropogenically unperturbed sediment cores has not been shown. Here we show that the AMS 14C-based long-term mass accumulation rate (MAR) of an organic-rich (>70%) sediment core from Mud Lake, Florida to be ∼5 times lower than the short-term MAR obtained using 239,240Pu, 137Cs and excess 210Pb (210Pbxs). The measured sediment inventories of 210Pbxs, 137Cs and 239,240Pu are comparable to the atmospheric fallout for the sampling site, indicating very little accelerated sediment erosion over the past several decades. Presence of sharp fallout peaks of 239,240Pu indicates very little sediment mixing. The penetration depths of 137Cs and 239,240Pu were found to be much deeper than expected and this is attributed to their post-depositional mobility. MAR calculated using 14C-ages in successive layers also indicated decreasing MARs with depth, and was reflective of progressive remineralization. Using first-order kinetics, the sediment remineralization rate was found to be 4.4 × 10-4 y-1 and propose that over the long-term, remineralization of organic-rich sediment affected the long-term MAR, but not the ratio of 14C/12C. Thus, the MAR and linear sedimentation rate obtained using 14C (and other isotope-based methods) could be erroneous, although 14C ages may not be affected by such remineralization. Long-term remineralization rates of organic matter has a direct bearing on the biogeochemical cycling of elements in aqueous systems and mass balance of elements needs to be taken into consideration.

Treatment of Micrognathia by Intraoral Distraction Osteogenesis: A Prospective Study.

PURPOSE: Maxillofacial deformities are always psychologically and physically distressing to the patients and is also challenging to the treating surgeons. The term Micrognathia means a "small jaw". True micrognathia, where the maxilla or the mandibular skeleton does not grow to the full size can be congenital or acquired. Distraction osteogenesis also called as callus distraction or callostasis or osteodistraction or distraction histogenesis is a biological process of regenerating newly formed bone and adjacent soft tissue by a gradual and controlled traction of surgically separated bone segments. The purpose of this prospective study was to assess the versatility of distraction osteogenesis in the treatment of micrognathia. MATERIALS AND METHODS: Four patients (three males and one female) with micrognathia of mandible were included in this prospective study. The patients were between the age group of 10-20 years. Facial asymmetry was the chief complaint of all the patients. In all the patients following treatment protocol was carried out, Osteotomy and placement of intraoral distraction device under general anaesthesia, latency phase (5-7 days), activation period-rate 1.5 mm per day, consolidation period of 8 weeks, removal of distraction device under local anaesthesia. The parameters assessed were ramus height, body length, hyo mental distance, posterior pharyngeal airway space, chin projection, facial symmetry occlusion, mid line shift pre and post operatively. RESULTS: The mean increase in ramus height achieved was 9.2 + 2.17 mm and the mandibular body length achieved was 10.4+1.67 mm. There was an average increase in hyo-mental distance of 2.75 cm +0.9 cm postoperatively showing a definitive improvement in the airway. The posterior pharyngeal space measured from the lateral cephalogram preoperatively ranged from 3-6 mm and post operatively from 6-9 mm.Intraorally there was a shift in occlusion to class I molar relation in three patients and there was posterior open bite in one patient. Marked correction of facial asymmetry was noticed in all cases both clinically and in PA cephalogram. There was a restoration of dental as well as lip midline and improved lip competence. There was a significant improvement in chin projection and occlusal cant however further chin correction was needed in one case by means of advancement genioplasty. CONCLUSION: A definite improvement in all parameters such as body length,ramus height,chin projection,occlusal cant was observed in all patients. Moreover the patients were subjectively satisfied with the outcome of the results. Distraction Osteogenesis is definitely a boon to the oral and maxillofacial surgeons in treating large deficiencies of mandible in terms of stability.

OPTN gene: profile of patients with glaucoma from India.

PURPOSE: Optineurin gene (OPTN) mutations are reported in primary open angle glaucoma patients (POAG) from different populations. The coding and noncoding regions of OPTN were screened for mutations in 100 Indian high tension glaucoma patients (HTG). The frequency of the OPTN M98K mutation in an additional 120 patients (70 HTG and 50 normal tension glaucoma [NTG]) was analyzed by restriction enzyme digestion. METHODS: The HTG patients (about 40 years of age) were characterized by open angles on gonioscopy, with raised intraocular pressure (IOP) more than 21 mmHg (<21 mmHg on office diurnal phasing for NTG), and typical glaucomatous disc changes with corresponding visual field defects in the absence of any secondary cause. One hundred HTG patients and controls were screened for OPTN mutations by direct sequencing using an ABI prism 310/3100 Avant genetic analyzer. The M98K status was analyzed by restriction enzyme digestion with StuI. A genotype/phenotype correlation was also attempted for OPTN sequence alterations with clinical parameters such as age at diagnosis, intraocular pressure, cup:disc ratio, etc. The putative change in the transcription factor binding site for the IVS7 +24G>A polymorphism was attempted with AliBaba software (version 2.1). RESULTS: Six sequence alterations were observed in the 100 POAG patients by direct sequencing. The M98K substitution was observed in a total of 10 patients (7/170 HTG and 3/50 NTG) contributing to 4.1% in HTG and 6% in the NTG group and not in the controls. The IVS7+24G>A nucleotide change showed a significant difference in the HTG group (7/100) when compared to the control group (0/100) and found to be associated with increased IOP at diagnosis (p=0.03). The IVS7+24G>A polymorphism resulted in the creation of binding sites for transcription factors NF-1 and CPE that were not present in the wild type. CONCLUSIONS: The current study suggests a possible role of SNPs rather than mutations in OPTN in POAG pathology in the Indian population.

Prevalence of angle-closure disease in a rural southern Indian population.

OBJECTIVE: To estimate the prevalence of primary angle-closure glaucoma, primary angle closure (PAC), and primary angle-closure suspect (PACS) and its associated risk factors in a rural population in southern India. METHODS: Three thousand and nine hundred thirty-four (81.95%) of 4800 enumerated subjects aged 40 years or older underwent a complete ophthalmic examination, including compression gonioscopy. Glaucoma was diagnosed using International Society of Geographical and Epidemiological Ophthalmology classification. RESULTS: Data were analyzed for 3924 subjects (81.75%). Primary angle-closure glaucoma was diagnosed in 34 subjects (0.87%; 95% confidence interval [CI], 0.58 to 1.16) (27 women, 7 men). The mean intraocular pressure was 20.71 +/- 9.24 mm Hg. One subject (2.94%) was blind. Twenty-eight subjects (0.71%; 95% CI, 0.45 to 0.98) were diagnosed to have PAC (21 women, 7 men). Eleven subjects (39.3%) had an intraocular pressure greater than 21 mm Hg, 13 subjects (46.43%) had peripheral anterior synechiae, and 4 subjects (14.29%) had both. Two hundred forty-six subjects (6.27%; 95% CI, 5.51 to 7.03) had PACS (168 women, 78 men). Primary angle closure and primary angle-closure glaucoma were more common in women (age-adjusted odds ratio, 3.02; 95% CI, 1.66 to 5.51) with an increasing prevalence with age. Increasing intraocular pressure was associated with the disease (odds ratio, 1.14; 95% CI, 1.09 to 1.19). There was no association with hypertension and hyperopia. Axial length and anterior chamber depth were longer in the normal group than in the 3 groups with angle closure (P<.05). Women had shorter axial lengths than men (P<.001) in the angle closure groups. CONCLUSIONS: The overall prevalence of primary angle closures (PAC and primary angle-closure glaucoma) in a rural population of southern India was 1.58%. There was a female preponderance, and the disease tends to be asymptomatic.

Influence of tobacco use on cataract development.

AIM: To study the influence of tobacco use on cataract formation in a rural South Indian population. METHODS: 3924 subjects from the Chennai Glaucoma Study conducted in rural south India underwent a comprehensive eye examination, including Lens Opacities Classification System II grading. Information on tobacco use, type of tobacco (smoking and smokeless), duration and quantity of use was collected. RESULTS: 1705 (male:female (M:F) 1106:599) people used tobacco and were significantly older (mean (standard deviation (SD)) age 55.80 (10.64) years) than non-users (52.23 (10.51); p<0.001). 731 (M:F 730:1) people smoked, 900 (M:F 302:598) used smokeless tobacco, and 74 (M:F, 74:0) used tobacco in both forms. The unadjusted and adjusted (age and sex) odds ratio (OR) for a positive history of tobacco use and cataract was 1.72 (95% confidence interval (CI) 1.51 to 1.96) and 1.39 (95% CI 1.15 to 1.68), respectively. The unadjusted OR for smokers and smokeless tobacco users was 1.04 (95% CI 0.88 to 1.23) and 2.74 (95% CI 2.31 to 3.26), respectively. The adjusted OR was 1.19 (95% CI 0.89 to 1.59) and 1.54 (95% CI 1.22 to 1.95), respectively. No significant association was noted between smoking and any particular type of cataract. Smokeless tobacco use was found to be significantly associated with nuclear cataract even after adjusting for age and sex (OR 1.67, p = 0.067, 95% CI 1.16 to 2.39). CONCLUSION: Tobacco use was significantly associated with cataract. Smoking was not found to be significantly associated with cataract formation; however, smokeless tobacco use was more strongly associated with cataract.

Central corneal thickness and its relationship to myopia in Chinese adults.

AIM: To investigate the association between central corneal thickness (CCT) and the degree of myopia among Chinese. METHODS: In this prospective observational study, 714 consecutive patients were recruited from a refractive surgery clinic. CCT was measured in both eyes of each patient using the Orbscan (Bausch and Lomb, Rochester, New York, USA), and data of the right eye were selected for analysis. CCT was correlated with the degree of myopia in dioptres (D) using Pearson's correlation coefficient and Dunnett's t test with multiple comparisons. RESULTS: The age of the patients ranged from 15 to 59 years. The mean CCT was 534.5 microm, with a standard deviation (SD) of 38.1 (range 305-684) microm. The mean (SD) myopic spherical equivalent was 5.30 (2.74) D, range -17.5--0.625 D. No correlation was found between CCT and the degree of myopia (r = -0.13, p = 0.719). CONCLUSIONS: Among Chinese with myopia, CCT was distributed over a large range but did not correlate with the degree of myopia.

Prevalence and causes of blindness in the rural population of the Chennai Glaucoma Study.

AIM: To study the prevalence and causes of blindness in a rural south Indian population. METHODS: 3924/4800 enumerated (81.75%) subjects, aged 40 years or more from rural Tamil Nadu, underwent comprehensive ophthalmic examination-visual acuity, refraction, intraocular pressure, gonioscopy, cataract grading (LOCS II), retinal examination, and SITA Standard where indicated. Blindness was defined using WHO criteria as best corrected visual acuity of less than 3/60 and/or visual field of less than 10 degrees in the better eye. The influence of age, sex, literacy, and occupation was assessed using multiple logistic regression. RESULTS: 753 subjects (19.2%; 321 males, 432 females) presented with a visual acuity of <3/60; 132 subjects (3.36%, 95% CI: 2.80 to 3.93) were diagnosed to be blind. Cataract was responsible in 74.62% of eyes; glaucoma, cystoid macular oedema, optic atrophy, and corneal scars accounted for 3.79% each. Bilateral causes of blindness were cataract (78.63%), glaucoma (4.29%), optic atrophy (3.42%), cystoid macular oedema, and corneal scars (2.56% each). In 19 eyes (7.2%) the blindness was probably related to cataract surgery. Blindness was positively associated with increasing age (p<0.0001). CONCLUSION: 3.36% of the studied rural population was bilaterally blind, with cataract being the single most important cause.

Frosted cylindrical lens induced artefact on Humphrey automated perimetry.

BACKGROUND: The aim of this study was to assess the effect of a cylindrical corrective lens with frosted sides on Humphrey automated perimetry performed with a translucent spectacle occluder in the contralateral eye. METHODS: Ten healthy volunteers with cylindrical refractive errors of more than 1.50 DC had Humphrey visual fields (30-2) measured with the contralateral eye occluded with either a translucent spectacle occluder or an opaque patch. The order of testing with each occluder was randomised. Additionally, visual field examination with the opaque patch was performed on three volunteer subjects with deep-set eyes to establish the clinical significance of the frosted cylindrical lens induced artefact (CLA). The back vertex distances for the correcting lenses were measured for all tests. RESULTS: Eight out of 10 volunteers tested with the translucent occluder demonstrated CLA, which was absent when the opaque patch was used. The presence of an artefact corresponding to the axis of the cylinder was observed, when the vertex distance was more than 15 mm. Three subjects with deep-set eyes presented with CLA, even with the use of an opaque patch. DISCUSSION: Cylindrical lens artefacts can occur with increasing vertex distance when using a translucent spectacle occluder instead of an opaque patch. CLA is also seen in subjects with deep-set eyes.

A computed tomography study in the location of greater palatine artery in South Indian population for maxillary osteotomy.

INTRODUCTION: The greater palatine artery is one of the important feeding vessel to the maxilla. The surgeon should know the surgical anatomy of greater palatine artery to avoid trauma in maxilla which leads to ischemic problems. AIM: The CT evaluation of the distance between Pyriform aperture and the greater palatine foramen in various ages of both sexes. RESULT: The distance varies according to sex and age which are measured by CT and standardised. DISCUSSION: The lateral nasal osteotomy can be done upto 25 mm depth, instead of 20 mm. CONCLUSION: By this study it shows that the lateral nasal wall osteotomy can be performed without injury to greater palatine artery.

Diurnal intraocular pressure fluctuation and its risk factors in angle-closure and open-angle glaucoma.

PURPOSE: To evaluate intraocular pressure (IOP) fluctuation during office hours and its predictive factors in untreated primary angle-closure suspects (PACS); post-iridotomy primary angle closure (PAC) and primary angle-closure glaucoma (PACG) eyes with or without IOP-lowering medication(s) as appropriate and medically treated primary open-angle glaucoma (POAG) eyes. METHODS: One-hundred seventeen eyes (29 PACS, 30 PAC, 28 PACG, and 30 POAG) of 117 patients were included in this cross-sectional study. The subjects underwent hourly IOP measurements with Goldmann tonometer from 0800 to 1700 hours. Subjects with PAC and PACG had laser peripheral iridotomy at least 2 weeks prior to the inclusion. SD of office-hour IOP readings was the main outcome measure. RESULTS: IOP fluctuation differed between the groups (P=0.01; Kruskal-Wallis Test). Post hoc Mann-Whitney U-tests showed significantly less IOP fluctuation in PACS compared with PACG (P<0.01). Peak office-hour IOP was observed in the morning in untreated subjects and in the early afternoon in treated subjects. A stepwise linear regression model identified the presence of peripheral anterior synechiae (PAS), thickness of lens, large vertical cup-to-disc ratio (VCDR), and PAC category as significant predictive factors associated with office-hour IOP fluctuation. CONCLUSIONS: Diurnal IOP fluctuation in asymptomatic PACSs was less than that in treated PACG subjects and was at least comparable to that in treated PAC and POAG subjects. The greater the amount of PAS, the thicker the lens, the larger the VCDR, the greater was the IOP fluctuation during office hours.