Michael W. Rouse

Validity and Reliability of the Revised Convergence Insufficiency Symptom Survey in Children Aged 9 to 18 Years

Purpose. To assess the validity and reliability of the Convergence Insufficiency Symptom Survey (CISS) in children aged 9 to 18 years. The CISS is the primary outcome measure for a pilot study evaluating two different treatments for convergence insufficiency (CI). Methods. Children with CI were given the CISS twice to assess reliability. CISS scores for the first administration were also compared with scores from children with normal binocular vision to assess the validity of the CISS. Results. Forty-seven children with CI and 56 children with normal binocular vision participated in the study. Reliability was assessed using intraclass correlation and 95% limits of agreement for the children with CI. For children with CI, the intraclass correlation was 0.77 (95% confidence interval, 0.613 to 0.873), and the 95% limits of agreement were −10.2 to +12.1. The mean (±SD) CISS score was 30.8 ± 8.4 for the children with CI and 8.4 ± 6.4 for the children with normal binocular vision. These means were significantly different (p < 0.0001). Good discrimination (sensitivity, 96%; specificity, 88%) was obtained using a score of ≥16. Conclusions. Children with CI showed a significantly higher CISS symptom score than children with normal binocular vision. The results of the study indicate that the CISS is a valid and reliable instrument to use as an outcome measure for children aged 9 to 18 who are enrolled in clinical research concerning CI.

Frequency of Convergence Insufficiency Among Fifth and Sixth Graders

PURPOSE To estimate the frequency of convergence insufficiency (CI) and its related clinical characteristics among 9- to 13-year-old children. METHODS Fifth and sixth graders were screened in school settings at three different study sites. Eligible children with 20/30 or better visual acuity, minimal refractive error, no strabismus, and exophoria at near were evaluated according to a standardized protocol to determine the presence and severity of CI. These children were classified according to the presence and number of the following clinical signs: (1) exophoria at near > or =4delta than far, (2) insufficient fusional convergence, and (3) receded nearpoint of convergence. Also, children were classified as accommodative insufficient (AI) if they failed Hofstetters minimum amplitude formula or had greater than a + 1.00 D lag on Monocular Estimate Method retinoscopy. RESULTS Of 684 children screened, 468 (68%) were eligible for further evaluation. Of these, 453 had complete data on CI measurements and were classified as: no CI (nonexophoric at near or exophoric at near and < 4delta difference between near and far) (78.6%); low suspect CI (exophoric at near and one clinical sign: exophoria at near > or =4delta than far) (8.4%); high suspect CI (exophoric at near and two clinical signs) (8.8%); and definite CI (exophoric at near and three clinical signs) (4.2%). CI status varied according to ethnicity and study site (p < 0.0005), but not gender. The frequency of AI increased with the number of CI-related signs. For CI children with three signs, 78.9% were classified as also having AI. CONCLUSIONS These findings suggest that CI (defined as high suspect and definite) is frequent (13%) among fifth and sixth grade children. In addition, there is a high percentage of CI children with an associated AI.

Validity and reliability of the revised convergence insufficiency symptom survey in adults

Purpose:  To assess the validity and reliability of the revised Convergence Insufficiency Symptom Survey (CISS) in adults aged 19–30 years. The CISS was developed to be the primary outcome measure for studies evaluating various treatments for convergence insufficiency (CI).

Randomized clinical trial of treatments for symptomatic convergence insufficiency in children

OBJECTIVE To compare home-based pencil push-ups (HBPP), home-based computer vergence/accommodative therapy and pencil push-ups (HBCVAT+), office-based vergence/accommodative therapy with home reinforcement (OBVAT), and office-based placebo therapy with home reinforcement (OBPT) as treatments for symptomatic convergence insufficiency. METHODS In a randomized clinical trial, 221 children aged 9 to 17 years with symptomatic convergence insufficiency were assigned to 1 of 4 treatments. MAIN OUTCOME MEASURES Convergence Insufficiency Symptom Survey score after 12 weeks of treatment. Secondary outcomes were near point of convergence and positive fusional vergence at near. RESULTS After 12 weeks of treatment, the OBVAT groups mean Convergence Insufficiency Symptom Survey score (15.1) was statistically significantly lower than those of 21.3, 24.7, and 21.9 in the HBCVAT+, HBPP, and OBPT groups, respectively (P < .001). The OBVAT group also demonstrated a significantly improved near point of convergence and positive fusional vergence at near compared with the other groups (P <or= .005 for all comparisons). A successful or improved outcome was found in 73%, 43%, 33%, and 35% of patients in the OBVAT, HBPP, HBCVAT+, and OBPT groups, respectively. CONCLUSIONS Twelve weeks of OBVAT results in a significantly greater improvement in symptoms and clinical measures of near point of convergence and positive fusional vergence and a greater percentage of patients reaching the predetermined criteria of success compared with HBPP, HBCVAT+, and OBPT. Application to Clinical Practice Office-based vergence accommodative therapy is an effective treatment for children with symptomatic convergence insufficiency. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00338611.

A Randomized Clinical Trial of Vision Therapy/ Orthoptics versus Pencil Pushups for the Treatment of Convergence Insufficiency in Young Adults

Purpose. The purpose of this article is to compare vision therapy/orthoptics, pencil pushups, and placebo vision therapy/orthoptics as treatments for symptomatic convergence insufficiency in adults 19 to 30 years of age. Methods. In a randomized, multicenter clinical trial, 46 adults 19 to 30 years of age with symptomatic convergence insufficiency were randomly assigned to receive 12 weeks of office-based vision therapy/orthoptics, office-based placebo vision therapy/orthoptics, or home-based pencil pushups. The primary outcome measure was the symptom score on the Convergence Insufficiency Symptom Survey. Secondary outcome measures were the near point of convergence and positive fusional vergence at near. Results. Only patients in the vision therapy/orthoptics group demonstrated statistically and clinically significant changes in the near point of convergence (12.8 cm to 5.3 cm, p = 0.002) and positive fusional vergence at near (11.3&Dgr; to 29.7&Dgr;, p = 0.001). Patients in all three treatment arms demonstrated statistically significant improvement in symptoms with 42% in office-based vision therapy/orthoptics, 31% in office-based placebo vision therapy/orthoptics, and 20% in home-based pencil pushups achieving a score <21 (our predetermined criteria for elimination of symptoms) at the 12-week visit. Discussion. In this study, vision therapy/orthoptics was the only treatment that produced clinically significant improvements in the near point of convergence and positive fusional vergence. However, over half of the patients in this group (58%) were still symptomatic at the end of treatment, although their symptoms were significantly reduced. All three groups demonstrated statistically significant changes in symptoms with 42% in office-based vision therapy/orthoptics, 31% in office-based placebo vision therapy/orthoptics, and 20% in home-based pencil push-ups meeting our criteria for elimination of symptoms.

Frequency of convergence insufficiency in optometry clinic settings

Purpose. To estimate the frequency of convergence insufficiency (CI) and its related characteristics among 8- to 12-year-old children randomly selected from 2 optometry clinic populations. Methods. Clinic records of 620 children were randomly selected and reviewed according to a standard protocol, using a systematic sampling method based on the total number of 8- to 12-year-old children seen over a 1-year period at 2 optometry clinics. Records were reviewed for demographic and clinical data. Data on CI-related symptoms were obtained at one of the sites. Records that met the eligibility criteria of: good visual acuity (20/30 or better in both eyes); minimal refractive error (–0.50 to +1.00 D and ≤1.00 D of astigmatism in either eye, and ≤1.00 D of anisometropia); and no strabismus were evaluated for Cl-related characteristics. Eligible children were classified according to the direction of their near heterophoria and the number of the following clinical signs present: (1) exophoria at near ≥4δ than at far; (2) insufficient fusional convergence [i.e., failing Sheards criterion or minimum normative positive fusional vergence (PFV) of 12 A base-out (BO) blur/15 A BO break]; and (3) receded nearpoint of convergence (NPC) of ≥7.5 cm break or ≥10.5 cm recovery. Children were then classified as: no Cl (nonexophoric at near or <4 δ difference between far and near); low suspect (exophoric at near and 1 sign); high suspect (exophoric at near and 2 signs); or definite Cl (exophoric at near and 3 signs). Results. Sixty-seven percent (415/620) of the records met the eligibility criteria and had complete data on phoria, NPC, and PFV. The age (mean ±SD) of the study population was 10.2 ±1.2 years. Ethnicity data were available for 85% of those eligible; the ethnic distribution was 36% African American, 29% Caucasian, 19% Hispanic, and 1% Asian. About one-half of the 415 children were classified as either low suspect (33%); high suspect (12%); or definite Cl (6%). Clinically significant Cl (high suspect and definite categories) was identified in 17.6% of the children. The percentage of children rated as symptomatic increased with the number of Cl-related clinical signs present. Conclusions. These findings suggest a high frequency of Cl in optometry clinic populations and a potential correlation between patient symptoms and the number of Cl signs present. (Optom Vis Sci 1998;75:88-96)

Randomised clinical trial of the effectiveness of base-in prism reading glasses versus placebo reading glasses for symptomatic convergence insufficiency in children

Purpose: To compare base-in prism reading glasses with placebo reading glasses for the treatment of symptomatic convergence insufficiency (CI) in children aged 9 to <18 years. Methods: In a randomised clinical trial, 72 children aged 9 to <18 years with symptomatic CI were assigned to either base-in prism glasses or placebo reading glasses. Symptom level, measured with a quantitative symptom questionnaire (CI Symptom Survey-V15), was the primary outcome measure. Near point of convergence and positive fusional vergence at near were secondary outcomes. Results: The mean (SD) CI Symptom Survey score decreased (that is, less symptomatic) in both groups (base-in prism glasses from 31.6 (10.4) to 16.5 (9.2); placebo glasses from 28.4 (8.8) to 17.5 (12.3)). The change in the CI Symptom Survey scores (p = 0.33), near point of convergence (p = 0.91), and positive fusional vergence (p = 0.59) were not significantly different between the two groups after 6 weeks of wearing glasses. Conclusions: Base-in prism reading glasses were found to be no more effective in alleviating symptoms, improving the near point of convergence, or improving positive fusional vergence at near than placebo reading glasses for the treatment of children aged 9 to <18 years with symptomatic CI.

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.

A normative study of the accommodative lag in elementary school children.

ABSTRACT Limited normative information is available regarding the accommodative lag of elementary school children. The accommodative lag of approximately 100 children in each of the grades kindergarten to grade six was measured using the Monocular Estimate Method (MEM) of dynamic retinoscopy. Children were selected on the basis of passing school screening using Modified Clinical Technique (MCT) criteria. Habitual spectacle corrections were worn and MEM retinoscopy was performed at the childs usual working distance. The mean lag for the total population of children was OD +0.33 D (±0.35), OS +0.35 D (± 0.34). Scatter plots show a weak relation between MEM and the other variables; however, the one‐way analysis of variance of MEM against age and grade show that a dependency exists.

Recovering viewer-centered depth from disparity, occlusion, and velocity gradients

Two experiments were conducted to assess the effects of corresponding and conflicting binocular and monocular information on the recovery of depth order (signed depth). Subjects viewed displays in which the same or opposite depth orders were indicated by disparity and occlusion, in one experiment, or by disparity and velocity gradients, in a second experiment. The same 36 subjects, 17 who had failed a Random Dot E test and 19 who had passed, were run in both experiments. When binocular and monocular information indicated conflicting depth orders, most subjects responded in accordance with the monocular information on some trials in both experiments. This was true even for a subgroup who always responded in accordance with the stereoscopic information on control trials that did not provide monocular information for depth order. For this subgroup, the impact of conflicting monocular information in the velocity gradient task correlated with performance on the uncrossed version of the Random Dot E test. We also found that some subjects who failed static tests of stereoscopic depth perception could respond accurately to continuously changing disparities.