Effectiveness of a novel mobile health (Peek) and education intervention on spectacle wear amongst children in India: Results from a randomized superiority trial in India.

BACKGROUND: Uncorrected refractive errors can be corrected by spectacles which improve visual functioning, academic performance and quality of life. However, spectacle wear can be low due to teasing/bullying, parental disapproval and no perceived benefit.Hypothesis: higher proportion of children with uncorrected refractive errors in the schools allocated to the intervention will wear their spectacles 3-4 months after they are dispensed. METHODS: A superiority, cluster-randomised controlled trial was undertaken in 50 government schools in Hyderabad, India using a superiority margin of 20%. Schools were the unit of randomization. Schools were randomized to intervention or a standard school programme. The same clinical procedures were followed in both arms and free spectacles were delivered to schools. Children 11-15 years with a presenting Snellen visual acuity of <6/9.5 in one or both eyes whose binocular acuity improved by ≥2 lines were recruited.In the intervention arm, classroom health education was delivered before vision screening using printed images which mimic the visual blur of uncorrected refractive error (PeekSim). Children requiring spectacles selected one image to give their parents who were also sent automated voice messages in the local language through Peek. The primary outcome was spectacle wear at 3-4 months, assessed by masked field workers at unannounced school visits. www.controlled-trials.com ISRCTN78134921 Registered on 29 June 2016. FINDINGS: 701 children were prescribed spectacles (intervention arm: 376, control arm: 325). 535/701 (80%) were assessed at 3-4 months: intervention arm: 291/352 (82.7%); standard arm: 244/314 (77.7%). Spectacle wear was 156/291 (53.6%) in the intervention arm and 129/244 (52.9%) in the standard arm, a difference of 0.7% (95% confidence interval (CI), -0.08, 0.09). amongst the 291 (78%) parents contacted, only 13.9% had received the child delivered PeekSim image, 70.3% received the voice messages and 97.2% understood them. INTERPRETATION: Spectacle wear was similar in both arms of the trial, one explanation being that health education for parents was not fully received. Health education messages to create behaviour change need to be targeted at the recipient and influencers in an appropriate, acceptable and accessible medium. FUNDING: USAID (Childhood Blindness Programme), Seeing is Believing Innovation Fund and the Vision Impact Institute.

Influence of disc area on retinal nerve fiber layer thickness measurement by spectral domain optical coherence tomography.

BACKGROUND: To examine the effect of optic disc area on peripapillary RNFLT (retinal nerve fiber layer thickness) measurement at circle diameter of 3.4 mm around optic nerve head using spectral OCT/SLO (Optical coherence tomography/scanning laser ophthalmoscope). MATERIALS AND METHODS: In this prospective, cross sectional study, one hundred and two eyes of 102 normal subjects underwent RNFLT and disc area measurement using spectral OCT/SLO. Based on disc area, subjects were divided into three groups i.e., <3 mm2 (32 eyes), 3-4 mm2 (36 eyes) and >4 mm2 (34 eyes). The effect of disc area on RNFLT parameters was analyzed using linear regression analysis. RESULTS: The mean and quadrant RNFLT did not show significant correlation with disc area in subjects with disc area of <4 mm2, however in eyes with disc area >4 mm2, average RNFLT, superior and temporal quadrant RNFLT showed negative correlation with disc area, which was statistically significant (P = 0.004, P = 0.005 and P = 0.002, respectively). CONCLUSION: In healthy eyes of disc area <4 mm2, disc size does not appear to affect peripapillary RNFLT measurement by spectral OCT/SLO. Average, superior and temporal quadrant RNFLT measurements were inversely proportional to disc area in eyes with disc area >4 mm2. Hence, RNFLT measurement by OCT in eyes with optic disc area of >4 mm2 should be interpreted carefully.

Quantification of retinal nerve fiber layer thickness after unilateral acute primary angle closure in Asian Indian eyes.

PURPOSE: To determine retinal nerve fiber layer thickness (RNFLT) using Spectral optical coherence tomography/scanning laser ophthalmoscope (Spectral OCT/SLO) in Asian Indian eyes after single, unilateral attack of acute primary angle closure (APAC). METHODS: Thirty-two patients with unilateral attack of APAC with normal optic disc and normal visual field, unaffected fellow eyes, and 35 age-matched normal control eyes were enrolled for the study. Six weeks after the remission of acute attack, peripapillary average, quadrant, and clock-hour RNFLT were compared between 3 groups using Spectral OCT/SLO. RESULTS: APAC patients had mean IOP of 51.3±13.3 mm Hg (range, 40-74) at the time of presentation with acute attack in the affected eye and 14.9±2.9 mm Hg at 6 weeks after resolution of APAC. Duration of symptoms of acute attack was 35.9±23.8 hours. Significant differences were found between RNFLT in APAC and fellow eyes for most the parameters except for 1, 4, 6, and 7-o'clock-hour sector. Most of the RNFLT parameters showed statistically significant difference between APAC and normal control eyes except for temporal quadrant, 6, 7-o'clock-hour sectors. Statistically significant differences were found between RNFLT in unaffected fellow and normal control eyes for most of the parameters except for 6, 7, 11 o'clock-hour sectors. CONCLUSIONS: RNFLT was found to be significantly thinner in APAC and unaffected fellow eyes when compared with normal age-matched controls. Hence, patients with APAC should be monitored carefully to determine its long-term effects on optic disc, RNFLT, and visual fields. Longitudinal studies can determine whether the RNFLT measurements remained stable or showed progression in these patients.

Quantification of retinal nerve fiber layer thickness using spectral domain optical coherence tomography in normal Indian population.

The purpose of this study was to measure peripapillary retinal nerve fiber layer thickness (RNFLT) using spectral domain optical coherence tomography (SD-OCT) in normal Indian eyes, for which, 210 normal volunteers were recruited. One eye of each subject underwent RNFL scanning at 3.4 mm circle diameter around optic nerve using SD OCT. The data were analyzed to determine RNFLT in the sample population and its variation with age and gender. The average peripapillary RNFLT was 114.03 ± 9.59 µm. There was no effect of gender on RNFLT parameters. Age had significant negative correlation with average (P = 0.005), superior (P = 0.04), temporal (P = 0.049), and nasal quadrants (P = 0.01) RNFLT. Inferior quadrant RNFLT also had a negative correlation with age, but it was not statistically significant (P = 0.15).

Ability of spectral domain optical coherence tomography peripapillary retinal nerve fiber layer thickness measurements to identify early glaucoma.

PURPOSE: To evaluate the ability of spectral domain optical coherence tomography (OCT) peripapillary retinal nerve fiber layer thickness (RNFLT) parameters to distinguish normal eyes from those with early glaucoma in Asian Indian eyes. DESIGN: Observational cross-sectional study. MATERIALS AND METHODS: One hundred and seventy eight eyes (83 glaucoma patients and 95 age matched healthy subjects) of subjects more than 40 years of age were included in the study. All subjects underwent RNFLT measurement with spectral OCT/ scanning laser ophthalmoscope (SLO) after dilatation. Sensitivity, specificity and area under the receiving operating characteristic curve (AROC) were calculated for various OCT peripapillary RNFL parameters. RESULTS: The mean RNFLT in healthy subjects and patients with early glaucoma were 105.7 ± 5.1 µm and 90.7 ± 7.5 µm, respectively. The largest AROC was found for 12 o'clock- hour (0.98), average (0.96) and superior quadrant RNFLT (0.9). When target specificity was set at ≥ 90% and ≥ 80%, the parameters with highest sensitivity were 12 o'clock -hour (91.6%), average RNFLT (85.3%) and 12 o' clock- hour (96.8 %), average RNFLT (94.7%) respectively. CONCLUSION: Our study showed good ability of spectral OCT/ SLO to differentiate normal eyes from patients with early glaucoma and hence it may serve as an useful adjunct for early diagnosis of glaucoma.

Reproducibility of peripapillary retinal nerve fibre layer thickness measurements with spectral domain optical coherence tomography in normal and glaucomatous eyes.

AIM: To determine reproducibility of peripapillary retinal nerve fibre layer thickness (RNFLT) measurements by spectral optical coherence tomography scanning laser ophthalmoscope (Spectral OCT/SLO) in normal and glaucomatous eyes. METHODS: 61 normal subjects and 41 glaucoma patients underwent three RNFLT measurement by Spectral OCT/SLO in one of the eyes with a rest of 1 h between each scan. The series was repeated on three different days within 1-month period. Intrasession, intersession reproducibility of average, quadrant and clock hour RNFLT measurements were calculated for both groups. All scans were acquired by a single operator after dilation. RESULTS: The intrasession intraclass coefficient correlations for mean RNFLT in normal and glaucomatous eyes were 0.994 and 0.998, respectively. The intrasession test coefficient of variation (CV) ranged from 1.2% for mean RNFLT to 5.1% for temporal clock hour in normal eyes and 1.3% for mean RNFLT to 3.6% for nasal quadrant in glaucomatous eyes. The intersession intraclass coefficient correlation for mean RNFLT in normal and glaucomatous eyes was 0.988. Intersession CV ranged from 3.96% for mean RNFLT to 9.56% for temporal clock hour in normal eyes and 3.28% for mean RNFLT to 13.39% for temporal clock hour in glaucoma patients. CONCLUSION: The RNFLT measurement showed increased variability for narrower peripapillary areas, nasal and temporal quadrants showed higher variability than superior and inferior quadrants in normal and glaucomatous eyes. Spectral OCT/SLO demonstrated excellent intrasession and intersession reproducible measurements of peripapillary RNFLT in both groups. This finding may be useful for diagnosis and monitoring the progression of glaucoma and other optic neuropathies with spectral OCT/SLO.

Optic disc topography in normal Indian eyes using spectral domain optical coherence tomography.

PURPOSE: The aim was to study optic nerve head (ONH) parameters in normal Indian eyes using spectral domain optical coherence tomography (OCT)/scanning laser ophthamoscope (SLO). MATERIALS AND METHODS: One hundred and fifty-seven eyes of 157 normal subjects of various age groups underwent ONH imaging with spectral OCT/SLO and the parameters obtained were correlated with disc size. The effect of age, gender, and refractive error on various ONH parameters were also studied. RESULTS: The mean optic disc area was 3.36 ± 0.64 mm 2 (range, 2.13-5.08 mm 2 ), mean rim area was 2.49 ± 0.58 mm 2 (range, 1.20-3.62 mm 2 ), and mean cup area was 1.10 ± 0.75 mm 2 (range, 0-3.07 mm 2 ). The disc area showed significant positive correlation with the rim area, cup area, horizontal cup disc ratio, vertical cup disc ratio, cup disc area ratio, mean cup depth, and maximum cup depth (P < 0.001). Neither gender nor refractive error showed any significant difference in various ONH parameters. ONH parameters did not show significant change with age except for rim area which declined with the advancing age (r = -0.25, P < 0.001). CONCLUSIONS: The quantitative measurement of ONH topography obtained with this study provides a normative database for an Indian population with spectral OCT/SLO. As optic disc area influences ONH topography, disc size should to be considered when evaluating optic disc for progressive optic neuropathies such as glaucoma.

Quantification of retinal nerve fiber layer thickness in normal eyes, eyes with ocular hypertension, and glaucomatous eyes with SD-OCT.

BACKGROUND AND OBJECTIVE: To quantitatively evaluate and compare retinal nerve fiber layer (RNFL) thickness between normal eyes, eyes with ocular hypertension (OHT), and glaucomatous eyes in an Indian population using spectral domain optical coherence tomography (SD-OCT). PATIENTS AND METHODS: Average and quadrant RNFL values were compared among three groups (66 normal eyes, 55 OHT eyes, and 51 glaucomatous eyes) and the discriminating power of each parameter was evaluated by calculating areas under receiver operator curves (AROCs). RESULTS: The mean RNFL thickness was 93.45 ± 16.9 µm in glaucomatous eyes, significantly less than in normal (112.48 ± 6.8 µm) and OHT (110.09 ± 10.9 µm) eyes. OHT eyes had significantly thinner RNFL thickness in the temporal quadrant (P = .006) than normal eyes. RNFL thickness in glaucomatous eyes differed significantly from normal eyes in most parameters except nasal quadrant (P = .1) and from OHT eyes in most parameters except temporal (P = .4) and nasal quadrants (P = .3). The parameter with the largest AROC to discriminate between OHT and normal eyes was temporal quadrant (0.65). Inferior quadrant RNFL thickness had the largest AROC (0.93) to distinguish between OHT and glaucomatous eyes and normal and glaucomatous eyes. CONCLUSION: SD-OCT identified differences in most parameters between eyes with glaucoma and normal eyes and also between eyes with glaucoma and OHT. Overlap of RNFL thickness between normal and OHT eyes limits the ability of this instrument to differentiate between normal and OHT subjects.

Correlation between peripapillary retinal nerve fiber layer thickness and optic nerve head parameters using spectral domain optical coherence tomography.

AIM: To evaluate correlation between peripapillary retinal nerve fiber layer thickness (RNFL) and optic nerve head (ONH) parameters in normal participants using Spectral domain optical coherence tomography (OCT). METHODS: Sixty-five eyes of 65 healthy participants aged 13-79 years underwent ONH analysis and peripapillary RNFL thickness measurements using spectral domain OCT. The RNFL measurements were correlated with the data obtained with ONH analysis. RESULTS: The average and quadrant RNFL thickness did not show correlation with optic disc area. A positive correlation was found between average RNFL thickness and rim area (r=0.425, P=0.000) and negative correlation between average RNFL thickness and cup area (r=-0.249, P<0.046). CONCLUSIONS: In our study, peripapillary RNFL thickness as measured by OCT did not show correlation with optic disc size. Despite a shorter distance between optic disc and circular scan margin, larger discs did not show a thicker RNFL. Interindividual variability of disc area probably minimizes the effect of various ONH size on RNFL thickness measurement.