Ocular convergence deficits in schizophrenia.

Individuals with schizophrenia (SZ) have been reported to exhibit a higher prevalence of convergence insufficiency (CI) than the "normal" adult population. The purpose of this study was to determine if individuals with SZ exhibit clinical signs of CI and to determine if the Convergence Insufficiency Symptom Survey (CISS) is an effective instrument for identifying CI in this population. Twenty participants with SZ and 20 healthy controls (HC) completed the study. The prevalence of CI (15%) in the SZ group was slightly higher than reported norms, but the difference was not significant. The SZ group had significantly higher scores on the CISS than the HC group, but the CISS scores did not correlate with clinical measures of CI in individuals with SZ. The only exception was that SZ patients had a significantly reduced fusional reserve as determined by Sheard's criteria. Further study is needed to determine why individuals with SZ reported symptoms associated with CI even though clinical measures did not support this diagnosis.

Objective measures of the effects of the "Read Without Glasses Method".

PURPOSE: The Read Without Glasses Method is a home-based vision training program designed to "avoid, eliminate, or reduce the need for bifocals" in presbyopic patients with 6 minutes of daily vision exercises. The purpose of this study was to objectively measure changes in accommodation and near unaided visual acuity (VA) in emmetropic presbyopes using this program. METHODS: Eight emmetropic presbyopes between 50 and 65 years of age participated in 2 pretreatment and 2 post-treatment visits. Primary outcome measures included near unaided VA (MNREAD acuity chart) and accommodative accuracy at near (Grand Seiko). Pupil size was measured at each visit during accommodative measures to assess the possibility that pupil size may have had an impact on near VA. Subjects were also queried about compliance and use of reading glasses after treatment. RESULTS: Repeated measures analysis of variance showed no significant change in unaided near VA pre- or post-treatment (p = 0.956). A statistically significant change in accommodation (0.176 D) was found at visit 3 (p = 0.0098) that did not persist at visit 4; however, this change was not clinically significant. Pupil size did not show significant change across all study visits. Survey results indicated that 87.5% of subjects reported that their near vision was slightly to significantly improved after the use of the program. CONCLUSIONS: The Read Without Glasses Method does not produce clinically or statistically significant changes in unaided near VA and fails to show clinically significant changes in accommodation at near in presbyopic emmetropes despite favorable subjective responses of participants.

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.

Reliability of the developmental eye movement test.

PURPOSE: This study evaluated the repeatability of the Developmental Eye Movement Test (DEM) with three consecutive administrations on two separate visits to 181 children between the ages of 6 years and 11 years 11 months. METHODS: Children with visual acuity of ≥ 20/25, normal binocularity, and accommodation were administered three different versions of the DEM test. One to 4 weeks after the first administration of the DEM, the children were tested again using the same order for the three versions of the DEM. Measures of within- and between-session repeatability for the vertical-adjusted time, horizontal-adjusted time, ratio, and error scores were determined. RESULTS: The within-session repeatability for vertical- and horizontal-adjusted time were good to excellent but were poor to good for ratio, and poor to fair for errors. The between-session intraclass correlation coefficients were fair to good for both the vertical and horizontal scores but poor for the ratio and error scores. The repeatability of the pass-fail diagnostic classification within a single session for each subject on test and retest was compared. The percentage of patients who remained in the same classification ranged from 71 to 100% for both vertical and horizontal scores. Wider variability was seen with the ratio and error scores showing between 47 and 100% of the children remaining classified as pass or fail with repeated administrations of the DEM. Such findings would suggest that children in this age range may show improvements in all four test scores without any intervention. CONCLUSIONS: Although the DEM is widely used in optometric practice, the results of this study suggest that clinicians should be cautious about using the DEM test in isolation for reaching a diagnosis or monitoring the effectiveness of treatment for saccadic dysfunction.

Treatment of accommodative dysfunction in children: results from a randomized clinical trial.

PURPOSE: To report the effectiveness of various forms of vision therapy/orthoptics in improving accommodative amplitude and facility in children with symptomatic convergence insufficiency (CI) and co-existing accommodative dysfunction. METHODS: In a randomized clinical trial, 221 children aged 9 to 17 years with symptomatic CI were assigned to one of four treatments. Of the enrolled children, 164 (74%) had accommodative dysfunction; 63 (29%) had a decreased amplitude of accommodation with respect to age, 43 (19%) had decreased accommodative facility, and 58 (26%) had both. Analysis of variance models were used to compare mean accommodative amplitude and accommodative facility for each treatment group after 4, 8, and 12 weeks of treatment. RESULTS: After 12 weeks of treatment, the increases in amplitude of accommodation [office-based vergence/accommodative therapy with home reinforcement group (OBVAT) 9.9 D, home-based computer vergence/accommodative therapy group (HBCVAT+) 6.7 D, and home-based pencil push-up therapy group (HBPP) 5.8 D] were significantly greater than in the office-based placebo therapy (OBPT) group (2.2 D) (p-values ≤0.010). Significant increases in accommodative facility were found in all groups (OBVAT: 9 cpm, HBCVAT+: 7 cpm, HBPP: 5 cpm, OBPT: 5.5 cpm); only the improvement in the OBVAT group was significantly greater than that found in the OBPT group (p = 0.016). One year after completion of therapy, reoccurrence of decreased accommodative amplitude was present in only 12.5% and accommodative facility in only 11%. CONCLUSIONS: Vision therapy/orthoptics is effective in improving accommodative amplitude and accommodative facility in school-aged children with symptomatic CI and accommodative dysfunction.

Aniseikonia testing in an adult population using a new computerized test, "the Aniseikonia Inspector".

PURPOSE: To determine the measurement characteristics of a new computerized test, the Aniseikonia Inspector Version 1, on a sample of clinic patients. METHODS: Aniseikonia was measured in the vertical, horizontal, and oblique meridians on 320 patients (mean 55 years old, range 17-89 years) prior to their optometric exam using the psychometric methods programmed into the Aniseikonia Inspector Version 1. Statistical analyses were performed to determine the distribution of aniseikonia in the sample of patients and the relationships between the amount of aniseikonia and patients' habitual refractive correction, visual acuity, stereopsis and binocular alignment status. The characteristics of the individual measurements were also examined. RESULTS: The means and standard deviations of the measured aniseikonia in the vertical, horizontal, and oblique meridians were -0.5% (2.5%), -0.1% (3.3%) and 0.3% (2.8%) respectively. The means in the vertical and oblique meridians were significantly different from 0.0 (p=0.0001, p=0.0314) while that in the horizontal was not (p=0.61). The distributions of aniseikonia showed that 65.6%, 57.5% and 64.3% had within +/-1.0% aniseikonia in the vertical, horizontal and oblique meridians, respectively. Correspondingly, 16.9%, 25.6% and 25.8% had aniseikonia of +/-3.0% or greater. The discrepancy between these percentages and those expected in a normal distribution indicate that the distributions were significantly more peaked than a normal distribution. This departure from normal is due to a few extreme values in the tails. The magnitude of aniseikonia had no statistically significant relationship with the patients' habitual refractive correction, visual acuity or stereopsis. The effect of phoria on the amount of aniseikonia was significant, more so for measurements in the horizontal meridian. The individual measurements, which are the average of two trials using the method of adjustment, showed no significant bias, no relationship between the means and differences in the two readings, but large differences between the two readings. Measurements in the vertical direction seem to be more stable than those in the other two meridians. CONCLUSION: As measured with the Aniseikonia Inspector 1.0, the majority of the patients sampled in this study exhibited 1.0% or less aniseikonia and were therefore not likely to have symptoms related to aniseikonia. At least 17% of patients had 3.0% or greater aniseikonia measured in the vertical meridian. The Aniseikonia Inspector warrants further evaluation in a clinical setting because of the large limits of agreement between the two settings that are average to determine the magnitude of the aniseikonia. These limits differ considerably from those established by the designers and, therefore, raise questions regarding the actual resolution of the instrument as compared to the nominal resolution.