Katherine K. Weise

Effect of Age on Response to Amblyopia Treatment in Children

OBJECTIVE To determine whether age at initiation of treatment for amblyopia influences the response among children 3 to less than 13 years of age with unilateral amblyopia who have 20/40 to 20/400 amblyopic eye visual acuity. METHODS A meta-analysis of individual subject data from 4 recently completed randomized amblyopia treatment trials was performed to evaluate the relationship between age and improvement in logMAR amblyopic eye visual acuity. Analyses were adjusted for baseline amblyopic eye visual acuity, spherical equivalent refractive error in the amblyopic eye, type of amblyopia, prior amblyopia treatment, study treatment, and protocol. Age was categorized (3 to <5 years, 5 to <7 years, and 7 to <13 years) because there was a nonlinear relationship between age and improvement in amblyopic eye visual acuity. RESULTS Children from 7 to less than 13 years of age were significantly less responsive to treatment than were younger age groups (children from 3 to <5 years of age or children from 5 to <7 years of age) for moderate and severe amblyopia (P < .04 for all 4 comparisons). There was no difference in treatment response between children 3 to less than 5 years of age and children 5 to less than 7 years of age for moderate amblyopia (P = .67), but there was a suggestion of greater responsiveness in children 3 to less than 5 years of age compared with children 5 to less than 7 years of age for severe amblyopia (P = .09). CONCLUSIONS Amblyopia is more responsive to treatment among children younger than 7 years of age. Although the average treatment response is smaller in children 7 to less than 13 years of age, some children show a marked response to treatment.

Validity of the convergence insufficiency symptom survey: a confirmatory study.

Purpose. The objectives of the present study were to evaluate whether investigator bias influenced the Convergence Insufficiency Symptom Survey (CISS) scores of children with normal binocular vision (NBV) in our original validation study, reevaluate the usefulness of the cutoff score of 16, and reexamine the validity of the CISS. Methods. Six clinical sites participating in the Convergence Insufficiency Treatment Trial (CITT) enrolled 46 children 9 to <18 years with NBV. Examiners masked to the child’s binocular vision status administered the CISS. The mean CISS score was compared with that from the children with NBV in the original, unmasked CISS study and also to that of the 221 symptomatic convergence insufficiency (CI) children enrolled in the CITT. Results. The mean (±standard deviation) CISS score for 46 subjects with NBV was 10.4 (±8.1). This was comparable with our prior unmasked NBV study (mean = 8.1 (±6.2); p = 0.11) but was significantly different from that of the CITT CI group (mean = 29.8 ± 9.0; p < 0.001). Eighty-three percent of these NBV subjects scored <16 on the CISS, which is not statistically different from the 87.5% found in the original unmasked study (p = 0.49). Conclusions. Examiner bias did not affect the CISS scores for subjects with NBV in our prior study. The CISS continues to be a valid instrument for quantifying symptoms in 9 to <18-year-old children. These results also confirm the validity of a cut-point of ≥16 in distinguishing children with symptomatic CI from those with NBV.

Stereoacuity in children with anisometropic amblyopia

PURPOSE To determine factors associated with pretreatment and posttreatment stereoacuity in subjects with moderate anisometropic amblyopia. METHODS Data for subjects enrolled in seven studies conducted by the Pediatric Eye Disease Investigator Group were pooled. The sample included 633 subjects aged 3 to <18 years with anisometropic amblyopia, no heterotropia observed by cover test, and baseline amblyopic eye acuity of 20/100 or better. A subset included 248 subjects who were treated with patching or Bangerter filters and had stereoacuity testing at both the baseline and outcome examinations. Multivariate regression models identified factors associated with baseline stereoacuity and with outcome stereoacuity as measured by the Randot Preschool Stereoacuity test. RESULTS Better baseline stereoacuity was associated with better baseline amblyopic eye acuity (P < 0.001), less anisometropia (P = 0.03), and anisometropia due to astigmatism alone (P < 0.001). Better outcome stereoacuity was associated with better baseline stereoacuity (P < 0.001) and better amblyopic eye acuity at outcome (P < 0.001). Among 48 subjects whose amblyopic eye visual acuity at outcome was 20/25 or better and within one line of the fellow eye, stereoacuity was worse than that of children with normal vision of the same age. CONCLUSIONS In children with anisometropic amblyopia of 20/40 to 20/100 inclusive, better posttreatment stereoacuity is associated with better baseline stereoacuity and better posttreatment amblyopic eye acuity. Even if their visual acuity deficit resolves, many children with anisometropic amblyopia have stereoacuity worse than that of nonamblyopic children of the same age.

Myopia Progression in Children Wearing Spectacles vs. Switching to Contact Lenses.

Purpose. To investigate myopia progression in Correction of Myopia Evaluation Trial (COMET) participants who switched to soft contact lenses (CLs) vs. remained in spectacles after the clinical trial ended. Methods. Four hundred sixty-nine ethnically diverse, 6- to 11-year-old myopic children were randomly assigned to wear single vision lenses (SVLs) or progressive addition spectacle lenses (PALs) for 5 years as part of COMET. Afterwards they could choose another lens type, including CLs. Data in this article are from 286 participants who wore their original spectacle lenses for 6 years (n = 199) or wore CLs most or all the time between the 5- and 6-year visits (n = 87). Refractive error and axial length (AL) were measured after cycloplegia with 1% Tropicamide. The primary outcome was myopia progression between the 5- and 6-year visits. Two-year myopia progression was evaluated in a subset of 183 participants who wore the same lens type for an additional year. Myopia progression and AL were compared between the two lens groups using multiple linear regression. Results. Participants in the two groups were similar with respect to age, ethnicity, myopia at 5-years, accommodation and phoria, but more girls switched to CLs than remained in spectacles (p < 0.0001). Mean (±SD) myopia progression was higher (p = 0.003) after 1 year in the CL group [−0.28 ± 0.33 diopter (D)] than the spectacle group (−0.14 ± 0.36 D), and remained higher after 2 years in the 2-year subset (−0.52 ± 0.46 D vs. −0.25 ± 0.39 D, p < 0.0001). Results were similar after adjustment for related factors. No significant differences in AL were found between groups after adjustment. Corneal curvature remained unchanged in both groups. Conclusions. COMET children switching from glasses to CLs experienced a small, statistically significant but clinically inconsequential increase in myopia progression.

Visual activity and its association with myopia stabilisation

To evaluate the association between outdoor and nearwork activities at baseline and myopia stabilisation by age 15 in the Correction of Myopia Evaluation Trial (COMET).

Academic Difficulty and Vision Symptoms in Children with Concussion.

PURPOSE Academic difficulty is reported in children with prolonged post-concussive symptoms. Despite growing evidence that vestibular-ocular and vision-specific dysfunction are common in children after concussion, vision is rarely mentioned in return-to-learn protocols. The purpose of this project was to evaluate a cohort of children with prolonged post-concussive symptoms to determine if vision symptoms are associated with those reporting academic difficulty. METHODS Data were obtained from the Childrens of Alabama Concussion Clinic REDCap dataset from the period January 2007 to October 2013. From this dataset of 1033 concussion events, a cohort of 276 children aged 5 to 18 years with three or more concussion-related symptoms present for 10 days or more was identified. A cross-sectional cohort study was undertaken to evaluate the association of concussion symptoms, SCAT2 scores, and demographic and concussion severity markers to reported educational difficulty among children with prolonged post-concussive symptoms. Univariate and multivariate logistic regression techniques were used to model the association of reported educational difficulty to self-reported vision abnormalities. RESULTS Mean age was 13.8 years. Median time since the concussive event was 21 days, with 33% (95/276) reporting their concussion more than 30 days before data collection. Academic difficulty was reported by 29% (79/270) and vision abnormalities in 46% (128/274). After model reduction, vision symptoms (OR 2.17, 95% CI 1.02, 4.62), hearing disturbance (OR 2.39, 95% CI 1.06, 5.36), and concentration difficulty (OR 21.62, 95% CI 9.50, 44.47) remained associated with academic difficulty. For those with symptoms 30 days or more after concussion, only vision (OR 3.15, 95% CI 1.06, 9.38) and concentration difficulty (OR 15.33, 95% CI 4.99, 47.05) remained statistically significant. CONCLUSIONS Vision problems were commonly reported in children with concussions and were independently associated with those reporting academic difficulty. Comprehensive vision assessment should be considered in children reporting academic difficulty and in the development of return-to-learn protocols.

Intraocular Pressure and Central Corneal Thickness in the COMET Cohort

Purpose. To describe intraocular pressure (IOP) and central corneal thickness (CCT) in ethnically diverse, myopic young adults enrolled in COMET (the Correction of Myopia Evaluation Trial) and their association with ocular and demographic factors. Methods. IOP (Goldmann tonometry), CCT (handheld pachymetry), refractive error (cycloplegic autorefraction), and ocular components (A-scan ultrasonography) were measured in 385 of the original 469 subjects (mean age = 20.3 ± 1.3 years). Summary statistics for descriptive analysis, Pearson correlation coefficients, and linear regression models to formally test the association of IOP and CCT with other covariates were used. Results. Mean IOP was 15.1 ± 0.1 mm Hg and differed by ethnicity and CCT but did not vary by gender, magnitude of myopia, or vitreous chamber depth (VCD). Adjusting for CCT, IOP in black participants was 1.8 mm Hg higher than in Hispanics (p = 0.0001) and 0.8 mm Hg higher than in whites (p = 0.03). Mean CCT was 562.4 ± 1.8 &mgr;m and differed by ethnicity, VCD, and IOP after adjusting for covariates. Blacks had thinner corneas than Asians, whites, and Hispanics, with adjusted differences of 15.4, 11.8, and 15.3 &mgr;m (p = 0.03, < 0.01 and < 0.01), respectively. Eyes with shorter VCD (<17.8 mm) had 8.0-&mgr;m thinner CCT (p = 0.03). CCT did not vary by gender or magnitude of myopia. Overall, a modest positive correlation (r = 0.25, P < 0.0001) was found between IOP and CCT, which varied by ethnicity in Asians (r = 0.47; p = 0.008), blacks (r = 0.29; p = 0.002), and whites (r = 0.24; p = 0.002). Conclusions. Myopic, black young adults had higher IOP and thinner corneas relative to other ethnic groups, suggesting that evaluation of these parameters during routine examination of these individuals should begin at a young age. Their thinner CCT should also be considered in evaluations for refractive surgery.

A sloped piecemeal Gaussian model for characterising foveal pit shape

High‐quality optical coherence tomography (OCT) macular scans make it possible to distinguish a range of normal and diseased states by characterising foveal pit shape. Existing mathematical models lack the flexibility to capture all known pit variations and thus characterise the pit with limited accuracy. This study aimed to develop a new model that provides a more robust characterisation of individual foveal pit variations.

Limited Change in Anisometropia and Aniso-Axial Length Over 13 Years in Myopic Children Enrolled in the Correction of Myopia Evaluation Trial

PURPOSE We investigated changes in anisometropia and aniso-axial length with myopia progression in the Correction of Myopia Evaluation Trial (COMET) cohort. METHODS Of 469 myopic children, 6 to <12 years old, enrolled in COMET, 358 were followed for 13 years. Cycloplegic autorefraction and axial length (AL) in each eye were measured annually. The COMET eligibility required anisometropia (interocular difference in spherical equivalent refraction) of ≤ 1.00 diopter (D). For each child, a linear regression line was fit to anisometropia data by visit, and the regression slope b was used as the rate of change. Logistic regression was applied to identify factors for significant changes in anisometropia (b ≥ 0.05 D/y, or a cumulative increase in anisometropia ≥ 0.50 D over 10 years). Similar analyses were applied to aniso-AL. RESULTS A total of 358/469 (76.3%) children had refractions at baseline and the 13-year visit. The mean (SD) amount of anisometropia increased from 0.24 D (0.22 D) at baseline to 0.49 D (0.46 D) at the 13-year visit. A total of 319/358 (89.1%) had slopes |b| < 0.05 D/y and 39 (10.9%) had slopes |b| ≥ 0.05 D/y, with only one negative slope. Similarly, 334/358 (93.3%) children had little change in aniso-AL over time. The correlation between changes in anisometropia and aniso-AL over 13 years was 0.39 (P < 0.001). The correlation between changes in anisometropia and myopia progression was significant (r = -0.36, P < 0.001). No correlation was found between baseline anisometropia and myopia progression (r = -0.02, P = 0.68). CONCLUSIONS Myopia and axial length progressed at a similar rate in both eyes for most children in COMET during the period of fast progression and eventual stabilization. These results may be more generalizable to school-aged myopic children with limited anisometropia at baseline. (ClinicalTrials.gov number, NCT00000113.).

A randomized trial of adding a plano lens to atropine for amblyopia

BACKGROUND Some children have residual amblyopia after treatment with atropine eyedrops for amblyopia due to strabismus and/or anisometropia. We conducted a randomized clinical trial to evaluate the effectiveness of augmenting the effect of atropine by changing the lens over the fellow eye to plano in children with residual amblyopia. METHODS A total of 73 children 3 to <8 years of age (mean, 5.8 years) with stable residual amblyopia (range, 20/32 to 20/160, mean 20/63(+1)) were enrolled after at least 12 weeks of atropine treatment of the fellow eye. Participants were randomly assigned to continuing weekend atropine alone or wearing a plano lens over the fellow eye (while continuing atropine). The primary outcome was assessed at 10 weeks, and participants were followed until improvement ceased. RESULTS At the 10-week primary outcome visit, amblyopic-eye visual acuity had improved an average of 1.1 lines with the plano lens and 0.6 lines with atropine only (difference adjusted for baseline visual acuity = + 0.5 line; 95% CI, -0.1 to +1.2). At the primary outcome or later visit when the best-measured visual acuity was observed, the mean amblyopic-eye improvement from baseline was 1.9 lines with the plano lens and 0.8 lines with atropine only. CONCLUSIONS When amblyopic-eye visual acuity stops improving with atropine treatment, there may be a small benefit to augmenting atropine therapy with a plano lens over the fellow eye. However, the effect was not statistically significant, and the large confidence interval raises the possibility of no benefit or a benefit larger than we observed. A larger study would be necessary to get a more precise estimate of the treatment effect.