The Role of Telemedicine in Strabismus Assessment: A Narrative Review and Meta-Analysis.

Purpose: Strabismus is a common ocular condition requiring precise quantification of gaze deviation and qualification of strabismus category. Telemedicine refers to the use of technology to remotely diagnose and treat medical conditions. This narrative review aimed to assess the efficacy of a variety of telemedicine modalities for the assessment of strabismus. A secondary objective was to quantify overall accuracy, sensitivity, and specificity of automated methods using meta-analysis of available data. Methods: A literature search was conducted using the Ovid MEDLINE, Embase, and Cochrane Library data libraries. Keywords, including "strabismus," "phoria," "telemed*," and "telehealth," were used to locate relevant studies, with Medical Subject Headings terms, free text, and synonyms. No year restrictions were applied. Studies not in English were excluded. Risk of bias was assessed using the QUADAS-2 tool. Results: Thirty-four studies were included. All outcomes relating to accuracy and reliability of telemedicine versus a reference standard were extracted, as well as qualitative observations. High sensitivity, specificity, accuracy, and agreement were consistently shown across studies. Meta-analysis of two subsets featuring automated methods, for which relevant data were available, revealed a pooled accuracy of 0.877 (0.806-0.949), sensitivity of 0.856 (0.805-0.907), and specificity of 0.900 (0.845-0.954). Subcategories "remote standard assessment," "digital image analysis," "wearable devices," "mobile health (mHealth)," and "artificial intelligence" were independently examined. Conclusions: The majority of systems achieved parity with standard physician assessment, with the added benefit of eliminating subjectivity. Meta-analysis results suggest potential introduction of remote automated assessment where conventional assessment is unavailable, although accuracy of current technologies remains limited compared to in-person examination. Telemedicine modalities described offer convenience for patients, shorter examination times, and the potential to go beyond in-person assessments. The evidence gathered in this review supports the beginning of telemedicine integration into the world of strabismus diagnosis.

Refractive change in children with accommodative esotropia.

OBJECTIVE: To determine whether there is a measurable change in hyperopia in children with accommodative esotropia over time. METHODS AND ANALYSIS: A retrospective cohort of children with fully or partially accommodative esotropia diagnosed by age 7 years, followed to age 10 or older, and with at least two cycloplegic refractions, one before age 7 years and one after age 10 years. The annual change was calculated from linear mixed-effect models, overall and during two age periods with subgroup analysis by baseline refractive error (<4D, ≥4D) and type (partial, full) of accommodative esotropia. RESULTS: 405 subjects were studied. Mean age at first and last visit was 3.2 and 12.1 years, respectively, with mean 7.6 cycloplegic refractions. The annual change (95% CI) in refractive error was -0.071 (-0.087 to -0.055) D/yr. Between ages 3 and 7, hyperopia among children with baseline hyperopia <4D increased by 0.12 (0.08 to 0.16) D/yr, while hyperopia among those with baseline 4D or greater was stable (0.0D/yr, -0.03 to 0.04) (p<0.001). Hyperopia decreased from age 7 to 15 years in both subgroups: <4D subgroup -0.17 (-0.20 to -0.14) D/yr, ≥4D subgroup -0.18 (-0.21 to -0.15) D/yr (p=0.58). There was no significant difference in refractive change between fully (n=274) and partially (n=131) accommodative esotropia (p≥0.10). CONCLUSION: Hyperopia in children with accommodative esotropia is stable or increases up to age 7 years, depending on baseline hyperopia, but decreases gradually between ages 7 and 15 years regardless of baseline refractive error.

Prevalence and Onset of Pediatric Sickle Cell Retinopathy.

PURPOSE: Children with sickle cell hemoglobinopathy (SCH) can demonstrate proliferative retinopathy with vision loss, but lack of consensus exists regarding screening regimens. We sought to determine the prevalence, age at onset, and risk factors associated with sickle cell retinopathy (SCR) to inform development of screening guidelines for asymptomatic children. DESIGN: Retrospective cohort study. PARTICIPANTS: Children with SCH over a 4-year period. METHODS: Prevalences of any retinopathy, nonproliferative retinopathy (NPR), and proliferative retinopathy (PR), determined as proportions of all children examined, were calculated. Subgroup analyses were completed by SCH genotype. Ages at first diagnosis were reported using standard descriptive statistics. The association of potential risk factors with retinopathy were assessed using univariate and multivariate linear and logistic regression. MAIN OUTCOME MEASURES: Outcomes were prevalence, age at onset, and type of SCR, based on examination by an ophthalmologist. Markers of SCH severity (number of emergency room or hospital admissions for crises, number of blood transfusions, hydroxyurea therapy, transcranial Doppler-confirmed cerebral vasculopathy), genotype, gender, and race were evaluated as SCR risk factors. RESULTS: Of 398 children (mean age, 9.6±4.6 years; range 0-18 years), 208 (52%) showed sickle cell homozygote (SS) genotype, 113 (28%) showed sickle cell hemoglobin C (SC) genotype, and 77 (19%) showed trait genotype. Forty-eight children (12.1%) demonstrated SCR, 44 of 398 children (11.1%; 95% confidence interval, 8.3%-14.5%) demonstrated NPR, and 9 of 398 children (2.3%; 95% confidence interval, 1.2%-4.2%) demonstrated PR. Prevalence was higher for SC than SS genotype for NPR (21% vs. 9%) and PR (5% vs. 1%); onset for SC genotype was earlier than that for SS genotype for NPR (youngest diagnosis 4.8 vs. 6.1 years) and PR (12.2 vs. 15.4 years). No other risk factors were associated significantly with SCR. CONCLUSIONS: Clinical markers of SCH severity assessed were not associated with SCR and are not necessary for screening guidelines. Based on our study and literature review, although screening could begin at age 5 years for NPR, screening of children without ophthalmologic symptoms to identify treatment-requiring PR could begin later, at 9 years of age for SC and 13 years of age for SS.

Hydrophobic acrylic and plate-haptic silicone intraocular lens implantation in diabetic patients: pilot randomized clinical trial.

PURPOSE: To compare the capsular and uveal reaction after implantation of a plate-haptic silicone intraocular lens (IOL) (C11UB, Chiron) and a hydrophobic acrylic (AcrySof MA60, Alcon) IOL in diabetic patients. SETTING: Moorfields Eye Hospital and St. Thomas' Hospital, London, United Kingdom. METHODS: Thirty-five diabetic patients were recruited consecutively and randomly assigned to have implantation of either of the 2 IOLs. The percentage area of posterior capsule opacification (PCO), anterior capsule contraction (ACC), and postoperative inflammatory indices (flare and cells) were assessed objectively at 2 to 3 weeks, 6 months, and 1 year. Between-group and within-group analyses were conducted using the Student t test or Mann-Whitney test and Friedmann test, respectively. RESULTS: Between-group analysis showed the percentage area of PCO was significantly greater in patients with plate-haptic silicone IOLs at 6 and 12 months (P = .002). At 6 months, ACC was significantly greater in the plate-haptic group (P = .04), but the difference was not significant at 12 months. There was higher flare in the hydrophobic acrylic IOL group than in the plate-haptic silicone IOL group at 2 to 3 weeks (P = .08). Within-group analysis showed that over the follow-up period, the plate-haptic silicone group, but not the hydrophobic acrylic group, had a progressive increase in PCO (P = .003). In the hydrophobic acrylic group, but not the plate-haptic silicone group, there was a significant reduction in the mean anterior chamber flare value (P = .01). There was no significant difference in visual acuity or contrast sensitivity at any postoperative visit. CONCLUSION: In diabetic patients, hydrophobic acrylic IOLs can lead to an increased flare in the early postoperative period but they seem to be more favorable than plate-haptic silicone IOLs because the latter lead to more PCO.

Comparison of posterior capsule opacification rates between hydrophilic and hydrophobic single-piece acrylic intraocular lenses.

PURPOSE: To determine the effect of intraocular lens (IOL) material on the development of posterior capsule opacification (PCO) at 1 year. SETTING: Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. METHODS: One hundred six eyes of 53 patients with bilateral cataract and no other ocular comorbidity were prospectively randomized to receive a hydrophobic acrylic or hydrophilic acrylic single-piece IOL in the first eye to have surgery. The alternate IOL was implanted in the fellow eye 4 to 6 weeks later. All surgery was performed by a single surgeon. Postoperative follow-up was 1 day, 1 and 6 months, and 1 year. At each visit, the best corrected high- and low-contrast visual acuities were assessed and a high-intensity digital retroillumination photograph was taken. Posterior capsule opacification was assessed from the digital images by a single operator using a dedicated software program and calculated as the percentage area of opacified capsule. RESULTS: One year postoperatively, the median percentage area of PCO was 50.3% in the hydrophilic IOL group and 4.9% in the hydrophobic IOL group (P<.001). The difference in PCO was not accounted for by loss of contact between the capsulorhexis and IOL surface. Further analysis showed that lens epithelial cells tended to invade the posterior capsule at the haptic-optic junction. This was more marked in the hydrophilic IOL group. CONCLUSIONS: The rate of PCO was significantly higher with the hydrophilic IOL. However, the results cannot be attributed to the IOL material alone as they show the importance of both IOL material and design.

Correlation between the measurement of posterior capsule opacification severity and visual function testing.

PURPOSE: To develop software to measure the severity of posterior capsule opacification (PCO) using analysis of retroillumination images and to correlate the results with clinical evaluation of PCO severity and visual function. SETTING: Department of Physics, King's College, and Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. METHODS: A technique for calculating PCO severity was developed based on calculating the variance of intensity by transforming retroillumination images to a similar mean intensity. The computer-derived severity was compared to grading of clinical severity by 3 independent observers using a library of 100 retroillumination images ranging from clear posterior capsules to very severe PCO. The computer results were also compared with the following other current methods of measuring PCO: Evaluation of Posterior Capsule Opacification (EPCO), POCOman, and Automated Quantification of After-Cataract. A further 35 images were used to compare the results of computer-derived severity with the results of visual function analysis (high-contrast acuity, 100%; low-contrast acuity, 9%) using the Early Treatment Diabetic Retinopathy Study chart, contrast sensitivity testing using the Pelli-Robson chart, and glare assessment using the van den Berg straylight meter. RESULTS: The severity scores showed a good correlation with clinical severity scores for the library of images (r=0.86) and with severity scores using POCOman and EPCO (r=0.85 and r=0.81, respectively). The correlations with visual function tests were also good, with low-contrast visual acuity (9%) showing the best correlation (r=0.87). CONCLUSION: Variance in intensity of PCO was successfully used to calculate the severity of PCO.

POCOman: new system for quantifying posterior capsule opacification.

PURPOSE: To describe a new method of measuring posterior capsule opacification (PCO) and intraocular lens (IOL) rotation and report the validation of the method. SETTING: Ophthalmology Department, St. Thomas' Hospital, and Medical Imaging, Department of Physics, King's College, London, United Kingdom. METHOD: A new interactive software program, POCOman, was developed for the semiobjective assessment of PCO. Digital images of the posterior capsule, which can be acquired by any technique, are analyzed by the observer to determine the percentage area of PCO and assign a severity score. The system was validated by comparing it to clinical slitlamp evaluation of PCO and automated POCO system analysis using a library of 100 images taken from archives. The software also measures sequential IOL rotation for the evaluation of toric IOLs. RESULTS: An image could be analyzed in approximately 2 minutes. The results of the POCOman system correlated well with the results of the automated POCO system and clinical evaluation. CONCLUSIONS: The POCOman is an effective, user-friendly system for quantifying PCO. It can be obtained for free and has advantages over other methods.

Effect of 1-piece and 3-piece AcrySof intraocular lenses on the development of posterior capsule opacification after cataract surgery.

PURPOSE: To evaluate the effect of 1-piece and 3-piece hydrophobic acrylic intraocular lenses (IOLs) on posterior capsule opacification (PCO) after cataract surgery. SETTING: Ophthalmology departments of 3 hospitals in the United Kingdom and Germany and the Department of Physics at a United Kingdom university. METHODS: A series of 131 patients having cataract surgery had implantation of an acrylic 1-piece (SA30AL) or an acrylic 3-piece (MA30BA) IOL (AcrySof, Alcon). Surgery was performed according to standardized protocol by a single surgeon at each hospital. Posterior capsule opacification was assessed using digital retroillumination photography. All images were analyzed at a single center according to a standard protocol. Data were analyzed 6 months and 1 year after surgery. RESULTS: There was no statistically significant difference in the percentage area of PCO between the 1-piece (mean 16.0% +/- 15.7% [SD]) and 3-piece (mean 13.6% +/- 19.8%) cohorts 6 months and 1 year after surgery (P =.0664). CONCLUSION: There was no evidence of a difference in the area of PCO after cataract surgery between 1-piece and 3-piece IOLs, which were otherwise matched for material and lens geometry.

Predicting posterior capsule opacification: value of early retroillumination imaging.

PURPOSE: To investigate the value of early retroillumination imaging of the posterior capsule in predicting the eventual development of posterior capsule opacification (PCO). SETTING: Ophthalmology Department, St. Thomas' Hospital, and Department of Physics, King's College, London, United Kingdom. METHODS: All patients with retroillumination images of the posterior capsule taken 6 months and 2 years after uneventful phacoemulsification with in-the-bag intraocular lens (IOL) implantation were selected. The images were taken using the same hardware and analyzed with the same software to calculate the percentage area of the posterior capsule covered by lens epithelial cells. The percentage area of PCO with all IOL types 6 months postoperatively was correlated with that at 2 years. RESULTS: One hundred forty patients had analyzable images at 6 months and 2 years. Of these, 63 had a poly(methyl methacrylate) (PMMA) IOL (Pharmacia 812A or Storz P497UV), 33 an acrylic (Alcon AcrySof MA30 or SA30), 22 a silicone (Allergan SI-30), and 22 a hydrophilic acrylic (Bausch & Lomb Hydroview H60). The correlation of the percentage area of PCO at 6 months with that at 2 years resulted in an r value of 0.71 (P <.0001) in the entire group. The r value was 0.48 in the PMMA group and 0.86 in the foldable IOL group (P <.0001) (r value: AcrySof, 0.66; silicone, 0.82; Hydroview, 0.75). CONCLUSIONS: Retroillumination imaging of the posterior capsule 6 months after cataract surgery predicted the PCO outcome at 2 years in eyes with foldable IOLs.