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Optical treatment is the primary treatment of all types of amblyopia that has a refractive component. However, it is unclear how optical treatment impacts cortical processing in amblyopic children as some of them may readily improve letter recognition visual acuity (treatment responders) but others may not (treatment non-responders). The main aim was to investigate the electrophysiological and psychophysical effects of optical treatment in children who have been newly-diagnosed with amblyopia in comparison with normal maturation in non-amblyopic children. The secondary aim was to explore whether pattern onset-offset visual evoked potentials (POVEPs) and psychophysical grating acuities (GA) may be predictive of clinically significant improvements in letter recognition visual acuity (VA) after four months of optical treatment. The primary outcome measures were POVEP C3 amplitude and C3 latency and GA which were assessed in response to orientation-specific stimuli. The testing protocol was designed to optimize the assessment of meridional anisotropies and was able to identify children with refractive amblyopia and to monitor treatment outcomes. The study presented evidence that four months of optical treatment improved POVEP C3 amplitude on average, although within the amblyopic group, a subset of refractive amblyopes were not found to significantly improve in letter visual acuity. A comparison control group, comprised of non-amblyopic children, were also monitored over two visits four months apart, which represented age-normal characteristics and maturation. Meridional anisotropies were found to be a potentially useful indicator of normality, as there was evidence that orientation-specific neural mechanisms differed for the responders and non-responders to optical treatment, with the responders showing anisotropies more consistent with the control data. An onset of horizontal effect may indicate that the amblyopic visual systems are improving. Consequently, lower POVEP C3 amplitude in response to horizontally oriented grating stimuli at baseline was found to be a potential predictor of responder status after four months of optical treatment. The findings added new knowledge into the understanding of the electrophysiological and psychophysical effects of optical treatment in refractive amblyopia.

Introduction: Convergence insufficiency (CI) is a common binocular vision disorder often associated with symptoms when completing near tasks. Vergence/accommodative therapy has been proven to improve symptoms and clinical signs in those with symptomatic CI. Previous literature has not examined the changes that occur in the brain after a course of real versus placebo therapy or using a stimulus with a wide of range vergence demands. The purpose of the current study was to show the changes that occur in the brain with CI therapy by examining the blood oxygenation level dependent (BOLD) signal during a functional magnetic resonance imaging (fMRI) scan before and after real and placebo treatment for convergence insufficiency.Methods: Adult subjects (n = 7, ages 18-30 years) were recruited and confirmed to have symptomatic CI according to the criteria set forth by the Convergence Insufficiency Treatment Trial (CITT) (symptomatic symptom score, exophoria at least 4 prism diopters (pd) greater at near than at distance, receded near point of convergence, insufficient positive fusional vergence). Eligible subjects underwent fMRI scanning while completing a series of vergence tasks. Subjects were then randomized into one of two treatment groups, office-based vergence accommodative therapy (OBVAT, n = 4) or office-based placebo therapy (OBPT, n = 3) in a 2:1 ratio, and completed 12 weeks of vision therapy following the CITT's treatment protocol. After treatment, subjects underwent a second fMRI scan while completing the same vergence tasks. Scans were analyzed with a two-tailed analysis comparing between pre- versus post-therapy scans in those who completed OBVAT and comparing OBVAT versus OBPT group post-therapy scans (OBVAT n = 3, OBPT n = 2).Results: The largest areas of activation were found in the occipital lobe. The largest areas of deactivation were generally found in the frontal lobe, but there was significant deactivation found in the occipital lobe pre-therapy and post-OBPT for a step vergence paradigm. A large decrease in spatial size of activation was seen post-OBVAT as compared to pre-therapy. In addition, the z-score value decreased among the areas that were common between the two. The areas of deactivation that were noted pre-therapy were resolved post-OBVAT when completing the easy step vergence paradigm and diminished when completing the hard step vergence paradigm. Post-OBPT showed a decrease in spatial size of activity when compared to the pre-therapy group as well, but not as much as post-OBVAT. The same overall pattern of activation areas was noted post-OBPT and pre-therapy. Regions of interest (ROIs) examined by other eye movement/vergence studies were examined and showed common areas of activation, but showed some difference, mainly in the frontal eye fields (FEF). Post-OBVAT, the active areas of the brain known to be devoted to attention were shown to suggest more of a bottom-up/stimulus driven attentional pathway rather than the top-down pathway noted pre-therapy and post-OBPT.Conclusion: The current study showed that vision therapy has an effect on the brain in symptomatic CI subjects.

Background: The Convergence Insufficiency Treatment Trial (CITT) illustrated that office-based vergence/accommodative therapy (OBVAT) was the most effective treatment of symptomatic convergence insufficiency (CI). However, the effect of completing specific OBVAT procedures has not yet been investigated.Purpose: This study evaluated the relationship between completion of each phase 3 CITT OBVAT procedures and change in the clinical signs and symptoms of CI (CI Symptom Score, near point of convergence [NPC], positive fusional vergence [PFV], accommodative amplitude [AA], and accommodative facility [AF]) from baseline to outcome.Methods: This was a secondary analysis of data from children aged 9 to < 18 years with symptomatic CI (N=59) who were randomized to and completed the CITT OBVAT. Analysis of Covariance (ANCOVA) was performed to compare the relationship between completing each phase 3 therapy exercise and change from baseline to outcome in measures of the clinical signs and symptoms of CI (CISS score, NPC, PFV, AA, and AF) while controlling for baseline and parent-reported ADHD measures. In addition, this study utilized a Pearson chi-square analysis to investigate whether completion of each phase 3 therapy exercise was associated with treatment outcome (i.e. whether a patient was defined as a success, improved, or a non-responder). A two-sample t-test was used to test whether completion of the various phase 3 therapy exercises was related to the time it took to complete the precursor phase 1 and/or phase 2 exercises. Pearson chi-square analysis was used to explore the relationship between completion of phase 3 procedures and compliance with either in-office or home therapy. Power analysis was also performed to investigate the study’s ability to recognize clinically meaningful differences based on the small and asymmetric group sizes.Results: Completion of phase 3 computer orthoptics was related to significantly greater improvements in PFV (p=0.029) and completion of vectograms was related to significantly greater improvements in AF (p=0.026). Changes in CISS score, NPC and AA were not associated with completion of any phase 3 therapy procedure. Having parent-reported ADHD did not have an effect on the patient’s ability to complete any of the phase 3 procedures (p-values > 0.55). The time it took to complete a precursor phase 1 and/or phase 2 therapy technique was significantly related to completion of phase 3 for vectograms, aperture rule, and binocular accommodative facility (p = 0.029 for all comparisons). Conclusion: Completion of phase 3 office-based computer orthoptics may be significantly associated with greater improvement in PFV.

Accommodative insufficiency is a binocular vision disorder characterized by a decrease in age expected amplitudes of accommodation. This condition can result in symptoms of headaches, blurred vision and asthenopia. Vision therapy has been utilized in helping treat patients with accommodative insufficiency. The purpose of this study was to evaluate the repeatability of the Convergence Insufficiency Symptom Survey (CISS) in subjects with accommodative insufficiency. This study also examined the improvement in CISS scores following 8 weeks of weekly 1-hour office-based vision therapy with home reinforcement. Improvements in accommodation and vergence measures were also examined as part of this study. Subjects ages 9 to 30 were enrolled in the study. Measures of amplitudes of accommodation, accommodative facility, accommodative response, and vergence function were evaluated at baseline and were repeated following 8 weeks of vision therapy. Final outcome sensorimotor measures and CISS scores were collected by examiners masked to the subject’s progress and compliance with vision therapy. Using the method described by Bland-Altman, the CISS was found to be repeatable in subjects with accommodative insufficiency. The mean difference in scores between two administrations was 1.47 point with 95% limits of agreement of -5.19 and 8.13. Analysis using student’s t or the Wilcoxan sign rank test showed a statistically significant improvement in amplitudes of accommodation (AA) (p

Purpose: The purpose of this study was to determine if using the Perceptual Therapy System II: PTS II iNet (PTS II), a computerized visual perception therapy program, would improve performance on standardized tests of visual perception and decrease the frequency of any reported problem behaviors. Methods: We recruited children ages 6 to 13 with below age-level performance on a standardized test of visual perception (the Beery-Buktenica Developmental Test of Visual Motor Integration, 5th Edition [VMI], the Beery VMI supplemental test of Visual Perception [VP], or the Test of Visual Perceptual Skills, 3rd Edition [TVPS-3]). Children who scored 80 or below on the Kaufman Brief Intelligence Test, 2nd edition (KBIT-2) were excluded. All patients were given the PTS II software and prescribed 16 weeks of home therapy. Baseline and outcome testing included the VMI, the VP, the TVPS-3 (Visual Discrimination, Visual Memory and Visual Sequential Memory), the Cognitive Assessment System (CAS) Figure Memory subtest and the Conners’ Parental Rating Scales-Revised (S) (Conners’). One sample t-tests were performed to compare the scores of participating children to normative values. Mann-Whitney analysis was used to compare scores at baseline to those at outcome. A multiple linear regression controlling for age, compliance and baseline score was used to evaluate whether there was a relation between change in test score and compliance. Results: Twenty children enrolled and sixteen children (mean age = 9.6 years) completed the study. At baseline, children scored on average significantly above the mean (indicating a higher frequency of problem behaviors) on the Conners’ (Cognitive Problems/Inattention scale, Hyperactivity scale, and ADHD Index) (p < 0.03 for all analyses) and significantly below the mean for all visual perceptual tests (p < 0.03 for all analyses) except the TVPS-3 Visual Memory (p = 0.28) and the CAS Figure Memory (p = 0.13). Children also scored below the mean on the KBIT-2 Non-verbal at baseline. Overall, excluding those who did not finish the study, the children completed an average of 59.5 sessions (range: 10.8 to 99.0 sessions). The outcome exam occurred on average at 19.5 weeks (range: 15.6 to 28.1 weeks). The frequency of problem behaviors as reported by the Conners’ decreased significantly from baseline to outcome: Oppositional (p=0.04); Cognitive Problems/Inattention (p = 0.001); and ADHD Index (p = 0.002). No significant changes in visual perceptual skill were found.Conclusion: The use of the PTS II resulted in a decreased frequency of parent-reported problem behaviors as measured by the Conners’. Further research with a larger sample size and a control group is needed.

PURPOSE: To prospectively evaluate the effectiveness of home-based computer vergence therapy for treatment of binocular vision disorders in adults, ages 18-85, at least 3 months post brain injury. METHODS: Eligibility criteria included presence of binocular or accommodative dysfunction characterized by receded near point of convergence (NPC) (greater than or equal to 6 cm break), insufficient positive fusional vergence (PFV) at near (failing Sheard’s criterion or less than 15Δ blur or break), insufficient negative fusional vergence (NFV) at near (less than 12Δ blur or break), reduced vergence facility with 12ΔBO/3ΔBI at near (less than 15 cpm), and/or below minimum expected amplitude of accommodation for age. All subjects were prescribed 12 weeks of home-based computer vergence therapy. Phoria (cover test), NFV at near, PFV at near, NPC, vergence facility, accommodative amplitude and facility (nonpresbyopes only), and symptoms (convergence insufficiency symptom survey [CISS]) were assessed at baseline and after 4, 8 and 12 weeks of prescribed therapy. ANOVA was used to evaluate change in each measure. Percent successful also was determined. RESULTS: Of the 19 subjects enrolled (mean age 45.4 ± 12.9 years), 15 suffered external mechanical trauma to the head, 3 suffered cerebrovascular accident, and 1 suffered from organic brain syndrome. Six subjects were lost to follow-up. The binocular profile of the cohort at baseline was orthophoria (SD=1.08) at distance, 7.11Δ (SD=5.19) exophoria at near, NPC break = 17.07 cm (SD=10.56), NPC recovery = 21.48 cm (SD=11.66), near NFV = 12.33Δ (SD=4.37), near PFV = 8.80Δ (SD=5.69), vergence facility = 4.06 cpm (SD=4.41), and CISS = 31.12 (SD=12.93). ANOVA showed statistically significant improvement for NPC break (p=0.002) and recovery (p less than .001), PFV blur (p less than .0001), break (p less than .0001), and recovery (p less than .0001), NFV blur (p=0.047), break (p=0.008), and recovery (p=0.017), vergence facility (p less than .0001), and CISS (p less than .0001). The percentage of patients who were classified as “successful” or “improved” was 69% for NPC (less than 6 cm or a decrease of greater than 4 cm), 77% for PFV (greater than 15Δ and passing Sheard’s criterion or an increase of greater than or equal to 10Δ), 77% for NFV (greater than or equal to 12Δ or an increase of greater than or equal to 6Δ), 69% for PFV and NFV, 92% for vergence facility (15 cpm or an increase of 3 cpm), and 62% for CISS (less than 21 or a decrease of greater than or equal to 10 points).CONCLUSIONS: The majority of the 68% of subjects who completed the study experienced meaningful improvements in signs and symptoms.