Development and validation of the Thai version of MNREAD acuity charts.

PURPOSE: To develop and validate MNREAD acuity charts in the Thai language (MNREAD-TH). METHODS: In total, 180 Thai sentences were generated using words specific to the primary 1-3 students. Each sentence contained 60 characters divided into three lines with even left and right margins and was evaluated by instructors in the education program in Thai. The selected 118 sentences were tested in 20 adults and 20 children by measuring reading time and recording the errors. Sentences with extremely high or low mean reading speeds were excluded. The remaining sentences were selected for contributing to the MNREAD-TH charts. For validation, the charts were tested in another 20 normal-sighted adult groups. RESULTS: In total, 118 sentences were tested on 20 adults (range: 23-58 years) and 20 primary school students (age: 8-9 years). The mean (SD) reading speeds in adult and children's groups were 134.09 (12.45) and 71.33 (10.77) words/min (wpm), respectively. After removing the sentences that deviated by ±1 SD from the mean reading speed, repeatedly had difficulty words, and had low subjective scoring, 60 matched sentences between the groups were selected to develop three versions of the MNREAD-TH chart. The intraclass correlation coefficients between charts were 0.85 for reading acuity, 0.94 for maximum reading speed, and 0.79 for critical print size. CONCLUSION: The MNREAD-TH charts can be reliably used for evaluating reading performance in Thai people for both children and adults with either normal sight or low vision. These charts are standardized and helpful in clinical trials involving reading.

Efficacy of wheat hot pack (dry heat) and pottery hot pack (moist heat) on eyelid temperature and tissue blood flow in healthy eyes: a randomized control trial.

PURPOSE: To investigate the eyelid temperature (Temp) and tissue blood flow (TBF) changes in healthy eyes using wheat hot pack (WHP) and pottery hot pack (PHP). METHODS: A randomized, double-blind, within-subject crossover study design was conducted in a Thai tertiary care center. All healthy subjects received warm compress treatment with WHP and PHP. The subjects were randomized to receive the WHP or the PHP at the first sequence. Temp and TBF measurements were taken at baseline, and every 2 min during the 10-min application of the heated compresses, and every 2 min for a 10-min duration after the compresses were removed. RESULTS: There were 29 females (96.7%) and 1 male. The mean (SD) age of the subjects was 33.17 (5.21) years. Two warm compresses were able to increase the surface lid Temp significantly from the baseline Temp at every time point of measurement and location. For the WHP application, the maximum surface Temp (SD) of the outer upper lid, outer lower lid, and inner lower lid were 40.07 (0.80) °C, 38.44 (0.91) °C, and 35.83 (0.71) °C, respectively (all P value < 0.001) and under the PHP application, the highest surface Temp (SD) were 40.63 (0.97) °C, 38.32 (1.27) °C, and 35.82 (0.71) °C, respectively (all P value < 0.001). Both WHP and PHP were able to increase TBF significantly with no adverse events and these effects can be sustained until 20 min. CONCLUSIONS: The results of this study suggest the potential of using these warm compresses for meibomian gland dysfunction. Further clinical research is needed.

Accuracy of computer-assisted vertical cup-to-disk ratio grading for glaucoma screening.

PURPOSE: Glaucoma screening can be performed by assessing the vertical-cup-to-disk ratio (VCDR) of the optic nerve head from fundus photography, but VCDR grading is inherently subjective. This study investigated whether computer software could improve the accuracy and repeatability of VCDR assessment. METHODS: In this cross-sectional diagnostic accuracy study, 5 ophthalmologists independently assessed the VCDR from a set of 200 optic disk images, with the median grade used as the reference standard for subsequent analyses. Eight non-ophthalmologists graded each image by two different methods: by visual inspection and with assistance from a custom-made publicly available software program. Agreement with the reference standard grade was assessed for each method by calculating the intraclass correlation coefficient (ICC), and the sensitivity and specificity determined relative to a median ophthalmologist grade of ≥0.7. RESULTS: VCDR grades ranged from 0.1 to 0.9 for visual assessment and from 0.1 to 1.0 for software-assisted grading, with a median grade of 0.4 for each. Agreement between each of the 8 graders and the reference standard was higher for visual inspection (median ICC 0.65, interquartile range 0.57 to 0.82) than for software-assisted grading (median ICC 0.59, IQR 0.44 to 0.71); P = 0.02, Wilcoxon signed-rank test). Visual inspection and software assistance had similar sensitivity and specificity for detecting glaucomatous cupping. CONCLUSION: The computer software used in this study did not improve the reproducibility or validity of VCDR grading from fundus photographs compared with simple visual inspection. More clinical experience was correlated with higher agreement with the ophthalmologist VCDR reference standard.

Incidence of short-term complications and associated factors after primary trabeculectomy in Chiang Mai University Hospital.

BACKGROUND: To determine the incidence of early postoperative complications and associated factors after primary trabeculectomy in Thai glaucoma patients. DESIGN: This was a retrospective observational study performed in Chiang Mai University Hospital. PARTICIPANTS: One hundred and eighteen glaucoma patients participated in the study. METHODS: All glaucoma patients underwent primary trabeculectomy with mitomycin C (MMC) using fornix-based conjunctival flap technique between December 2011 and May 2013. Surgical complications during the first 3 months of follow-up were recorded, and associated risk factors were analyzed. MAIN OUTCOME MEASURES: The incidence of posttrabeculectomy complications was the main outcome measure. RESULTS: One hundred and eighteen eyes of 118 patients were included. Early postoperative complications developed in 55 eyes (56.7%). Complications included hypotony (25 eyes, 27.2%), serous choroidal detachment (CD) (14 eyes, 15.6%), subconjunctival hemorrhage (12 eyes, 13.0%), hyphema (11 eyes, 12.4%), bleb leak (8 eyes, 8.8%), encapsulated bleb (2 eyes, 2.2%), aqueous misdirection (1 eyes, 1.1%), corneal epithelial defect (1 eyes, 1.1%), and overfiltration (1 eyes, 1.1%). There were no reported cases of endophthalmitis or blebitis. Hypotony was associated with serous CD (P = 0.006), and hyphema was associated with neovascular glaucoma (NVG) patients (P = 0.009). NVG was not associated with the increased rate of surgical failure (P = 0.083). CONCLUSIONS: The incidence of early complications after first-time trabeculectomy with MMC was high (56.7%) in this Thai clinic setting, but most were transient and self-limited conditions. The correlations between hypotony and CD as well as hyphema and NVG were compatible with the previous studies.

Work-Related Eye Injuries: Important Occupational Health Problem in Northern Thailand.

PURPOSE: This study was aimed to determine demographics, clinical characteristics, and factors associated with work-related eye injury in Northern Thailand. DESIGN: A prospective case series. METHODS: Eye injuries from any cause treated at a university-based hospital in Northern Thailand from March 2007 to June 2008 were included. In addition to comprehensive eye examination and standard treatments, patients' occupation, type of activity at the time of injury, alcohol consumption, and eye protection were studied. Eye injuries were classified based on the Birmingham Eye Trauma Terminology System. Demographic and clinical data were documented using a form adapted from the United States Eye Injury Registry. RESULTS: Of the 101 eyes (97 patients) with work-related injury, 94% were men with a mean age of 39.5 ± 12.9 years (range, 19-72 years). Ninety-eight percent (95/97 patients) did not use protective eyewear. Open-globe injuries were found in 58/101 (57%) eyes. Agricultural workers experienced a higher number of open-globe injuries (37/58 eyes, 64%), whereas construction workers experienced a higher number of closed-globe injuries (25/43 eyes, 58%). In multivariable logistic regression models, nailing (odds ratio, 97.2; 95% confidence interval, 2.6-363.4; P = 0.01) and motorized grass trimming (odds ratio, 14.3; 95% confidence interval, 1.0-206.2; P = 0.05) were significantly associated with open-globe injuries when compared with closed-globe injuries. Significantly greater numbers of eyes with open-globe injuries had final vision equivalent to legal blindness (visual acuity, <3/60) compared with closed-globe injuries (42% vs 12%, P = 0.001). CONCLUSIONS: Work-related open-globe injuries are relatively more common among agricultural workers in Northern Thailand. Protective eyewear should be aggressively promoted among workers engaged in nailing and motorized grass trimming.

Anatomic predictors for anterior chamber angle opening after laser peripheral iridotomy in narrow angle eyes.

PURPOSE: To investigate anterior chamber parameters and biometric factors associated with degree of angle opening after laser peripheral iridotomy (LPI) for narrow angles. METHODS: In this prospective cohort study, patients with narrow angles who were scheduled for LPI were recruited. Anterior chamber parameters by anterior segment coherence tomography (ASOCT) under dark conditions were compared before and after LPI. Only the right eye was used for analysis if both eyes were eligible. Measurements performed by customized software included anterior chamber depth, iris area, angle opening distance at 500 µm (AOD500) anterior to the scleral spur, iris thickness at 750 µm from sclera spur (IT750), trabecular-iris space area 500 (TISA500), and iris curvature (I-Curv). Univariate and multiple regression analyses were performed to determine the predictive factors of angle opening after LPI. RESULTS: Eighty-one patients with narrow angles were prospectively recruited in this study. The AOD500 increased significantly from 0.128 ± 0.081 mm (before) to 0.209 ± 0.087 mm (after) in the nasal quadrant, and from 0.103 ± 0.067 mm (before) to 0.197 ± 0.071 mm (after) in the temporal quadrant (p < 0.001 for both nasal and temporal). I-Curv decreased significantly after LPI (p < 0.001). Significant increase was noted in TISA500 before and after LPI (p < 0.001). In the multiple regression model, increase in AOD500 was positively correlated with age (standardized ß = 0.283, p = 0.007) and I-Curv (standardized ß = 0.239, p = 0.021), and was negatively correlated with preoperative iris area (standardized ß = -0.292, p = 0.015). CONCLUSIONS: In this hospital-based study on the results of LPI for narrow angle subjects, statistically significant independent predictors of anterior chamber angle widening after LPI were older age, smaller iris area, and steeper iris.

Plateau iris in Whites versus Asians.

PURPOSE: To evaluate the prevalence of plateau iris diagnosed by ultrasound biomicroscopy after laser peripheral iridotomy in Whites as compared to Asians in a U.S. clinic setting. METHODS: This was a prospective, observational study of narrow angle patients (n=55) who underwent laser peripheral iridotomy. Ultrasound biomicroscopy was performed in 4 quadrants of only one eye of each patient 4~6 weeks before and after surgery. The images were randomized and interpreted qualitatively by a single observer. Plateau iris was diagnosed in eyes with persistent appositional angles after laser peripheral iridotomy when at least 2 quadrants fulfilled the following criteria: 1. The ciliary process was directed anteriorly. 2. The ciliary sulcus was absent. 3. The central iris plane was flat. RESULTS: Twenty eight subjects (50.1%) were Whites, and 27 subjects (49.0%) were Asians. Plateau iris was assessed in 18 subjects (32.7%): 9 of 28 Whites (32.1%) and 9 of 27 Asians (33.3%). The proportion of plateau iris did not differ between Whites and Asians (P>0.99) CONCLUSION: The prevalence of plateau iris did not differ between Whites and Asians. Both groups had a substantial proportion of narrow angle patients with this clinical entity.

Anterior chamber depth, iridocorneal angle width, and intraocular pressure changes after phacoemulsification: narrow vs open iridocorneal angles.

OBJECTIVE: To determine the association of changes in anterior chamber angle and anterior chamber depth (ACD) with intraocular pressure (IOP) reduction after uncomplicated phacoemulsification. METHODS: In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or all quadrants was considered narrow angle (NA). Anterior segment optical coherence tomography and tonometry were performed preoperatively and 10 days and 1, 3, and 6 months after surgery. The ACD and angle opening distance at 500 µm anterior to the scleral spur (AOD500) were assessed from anterior segment optical coherence tomography. RESULTS: Data were collected from 63 eyes that underwent cataract surgery. Twenty-six eyes were classified as having NA. Before surgery, the mean (SD) AOD500 and ACD in the NA group were 0.179 (0.014) mm and 2.23 (0.07) mm, respectively. Six months after surgery, the mean (SD) AOD500 and ACD in the NA group were 0.389 (0.025) mm and 3.75 (0.05) mm, respectively. The postoperative IOP was reduced significantly in both groups. We found that each 0.1-mm increase in AOD500 corresponded to a mean (SD) 0.42 (0.18)-mm Hg decrease in IOP (P < .001) in the NA group and 0.32 (0.16) mm Hg (P = .046) in the OA group. CONCLUSIONS: Postoperative reduction in IOP was proportional to the increase in angle in both groups, but the IOP reduction per 0.1-mm increase in AOD500 in NA eyes was greater than that in OA eyes.