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Purpose: To evaluate the safety, validity, and comfort of 0.35% fluorexon disodium and 0.4% benoxinate (Flura-Safe) compared with the gold standard of 0.25% sodium fluorescein and 0.4% benoxinate for Goldmann applanation tonometry (GAT)., Methods: This was a double-masked, randomized, crossover clinical trial. Subjects received either the standard or study formulation for GAT on visit 1 and the other formulation 1 week later. At each visit, tonometer mire quality, adequacy of fluorescence, ease of intraocular pressure (IOP) measurements, the IOP value, and anesthetizing efficacy of the formulation were assessed. Subjects graded general comfort, soreness and irritation, and burning and stinging of each formulation at 1 and 5 minutes after drop instillation., Results: Sixty-seven subjects completed the study. The mean IOP was 13.9 +/- 2.7 with fluorexon and 13.9 +/- 2.8 mm Hg with fluorescein OD and 14.0 +/- 2.8 with fluorexon and 13.9 +/- 2.5 mm Hg with fluorescein OS. The measurements with the 2 formulations were highly correlated for OD and OS, and the differences between the 2 measurements were not clinically significant. There was also no significant difference between the 2 drops in mire clarity, adequacy of fluorescence, or corneal anesthesia. However, fluorexon was statistically more comfortable (P = 0.039) and caused less stinging and burning (P = 0.014) at 1 minute versus the fluorescein formulation., Conclusion: Not only was the new fluorexon product accurate and effective in GAT, it was also statistically more comfortable and had a less stinging and burning effect at 1 minute after drop instillation than the traditional fluorescein formulation. Because fluorexon is less likely to stain soft contact lenses, this may be the dye-anesthetic formulation of choice for practices that routinely perform GAT.

Purpose: Accommodative insufficiency (AI) and convergence insufficiency (CI) have been associated with similar symptomology and frequently present at the same time. The severity of symptomology in CI has been linked to the severity of the CI, suggesting a dose-dependent relationship. However, with increasing severity of CI also comes increased comorbidity of AI. AI alone has been shown to cause significant symptomology. We hypothesize that AI drives the symptoms in CI with a comorbid AI condition (CIwAI) and that it is the increased coincidence of AI, rather than increased severity of CI, which causes additional symptomology., Methods: Elementary school children (n = 299) participated in a vision screening that included tests for CI and AI and the CISS-V15 symptom survey. They were categorized into four groups:1) normal binocular vision (NBV); 2) AI-only; 3) CI-only; and 4) CIwAI. One hundred seventy elementary school children fell into the categories of interest., Results: Pairwise comparison of the group means on the symptom survey showed: 1) children with AI-only (mean = 19.7, p = 0.006) and children with CIwAI (mean = 22.8, p = 0.001) had significantly higher symptom scores than children with NBV (mean = 10.3); and 2) children with CI-only (mean = 12.9, p = 0.54) had a similar symptom score to children with NBV. Using a two-factor analysis of variance (AI and CI), the AI effect was significant (AI mean = 21.56; no AI mean = 11.56, p < 0.001), whereas neither the CI effect (p = 0.16) nor the CI by AI interaction effect (p = 0.66) were significant., Conclusion: CI is a separate and unique clinical condition and can occur without a comorbid AI condition, our CI-only group. Past reports of high symptom scores for children with CI are the result of the presence of AI, a common comorbid condition. When AI is factored out, and children with CI only are evaluated, they are not significantly more symptomatic than children with NBV.

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 Hofstetter's 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.

Purpose: To test the validity-related evidence of a child and a parent symptom survey developed by the Convergence Insufficiency and Reading Study (CIRS) group., Methods: A case comparison method was used to measure differences in symptoms between 14 school-aged children (ages 8 to 13 years) with Convergence Insufficiency (CI) and 14 children with normal binocular vision (NBV)., Results: A pooled t-test indicated that CI children and their parents scored higher than the NBV children and their parents on the child's survey (p<0.001) and parent's survey (p<0.001), respectively. CI children also scored significantly higher (p<0.03) on the Conners' Rating Scale for Parents., Conclusions: The results suggest that the CIRS symptom survey is a valid instrument for differentiating CI children from those with normal binocular vision. Additionally, children in this age group were able to respond to a broad range of symptom questions associated with CI.

Background: Nearpoint of convergence (NPC) values of 8 to 10 cm are widely used to diagnose binocular dysfunctions such as convergence insufficiency. However, there are no published age-related normative values in the literature to substantiate these values., Methods: Subjects were 297 schoolchildren in kindergarten, third grade, and sixth grade who had passed a school-based Modified Clinical Technique vision screening. Each child had the NPC break and recovery taken three times using a standardized protocol developed by the Convergence Insufficiency and Reading Study group. The examiners used an Astron International (ACR/21) Accommodative Rule with a movable column of 20/30 letters as the target., Results: For each grade, the distribution of NPC break was right skewed, with a concentration of values between 1 and 6 cm. At least 85% of the subjects in each grade had an NPC break < or = 6 cm. NPC break values (mean +/- SD) were 3.3 +/- 2.6 cm for kindergartners, 4.1 +/- 2.4 cm for third graders, and 4.3 +/- 3.4 cm for sixth graders, and the means were found to be statistically different (analysis of variance, p = 0.031). NPC recoveries (mean +/- SD) for the three groups were 7.3 +/- 4.8 cm, 8.7 +/- 4.2 cm, and 7.2 +/- 3.9 cm, respectively, which were also significantly different (analysis of variance, p = 0.027). The recovery distributions were more symmetric and less skewed than those for break. For each grade level, there was a strong positive relationship between NPC recovery and NPC break, but the difference between NPC recovery and break had a low correlation with the NPC break., Summary: Kindergartners had somewhat better NPC breaks than third or sixth graders, whereas no clear age trend was present for NPC recovery. A supporting study using a random sample of clinic patients (aged 10-12 years) suggests that patients with NPC breaks > 6 cm are more than twice as likely to be symptomatic than patients with NPC breaks < or = 6 cm. Based on these results and the NPC break distributions in this study, a clinical cutoff value of 6 cm is suggested for patients of elementary school age. A cutoff value in the 6- to 10-cm range is recommended for children of elementary school age in a screening context. The exact value within this range depends on the level of concern with identifying patients who have visual signs and symptoms associated with a receded NPC.

The effect of various hand washing regimens on transfer of bacterial contaminants from the hands to a hydrogel contact lenses was evaluated. Each of 47 subjects performed 5 different hand washing procedures, and then handled a new, sterile hydrogel contact lens. The lenses were cultured to determine colony-forming units (CFUs) and microbial identity. Median CFUs on lenses handled after washing with water, soap and water, or soap and water followed by towel drying were higher than the median CFU for lenses handled after no hand washing. The median CFU for lenses handled after soap and water washing followed by an alcohol wipe was not different from the no washing group. The majority of the contaminants were identified as Staphylococcus epidermidis. These results show that ordinary hand washing alone does not decrease, and may even increase, the amount of contaminants transferred from the hands to a hydrogel lens. Use of an alcoholic wipe after hand washing reverses this effect. Hand washing is still recommended in contact lens hygiene for removal of more pathogenic contaminants.

Background: Hydroxypropyl methylcellulose (HPMC), a popular gonioscopic solution, can cause discomfort and blurred vision. These side effects have been attributed to the preservative benzalkonium chloride (BAK). Carboxymethylcellulose (CMC), an unpreserved, viscous solution, might well provide adequate patient comfort and cushioning during gonioscopy without producing blur or irritation., Methods: The effects of CMC and HPMC during gonioscopy were evaluated in 55 human subjects. Corneal staining, comfort, subjective vision, and measured visual acuity (VA) were assessed., Results: In comparison with HPMC, CMC effected less corneal staining, greater comfort, and better vision after the procedure,, Conclusion: CMC proved to be a viable and superior alternative to HPMC as a gonioscopic solution.

Opinions differ concerning the relation between dyslexia and visual perception. In this pilot study we addressed this question by analyzing the results of visual perceptual testing on 19 elementary grade subjects diagnosed as having dyseidesia, one type of dyslexia that manifests as problems with sight-word recognition. The subjects, who have different degrees of severity of dyseidesia, were compared with 11 subjects tested as nondyslexic, but with reading problems. The Dyslexia Determination Test (DDT) and the Test of Visual Perceptual Skills (TVPS) were given to all subjects. Both multivariate analysis of variance (MANOVA) and univariate one-way analysis of variance (ANOVA) to test for differences in performance among four test groups (ranging from nondyslexic to increasing levels of severity of dyseidesia) showed no trends of either statistical or clinical importance. An individual with reading problems may be nondyslexic but have poor visual perceptual skills, or may be dyslexic with good visual perceptual skills. These results are consistent with the contention that reading problems caused by dyseidesia (as defined by the DDT) and those caused by visual perceptual deficiencies (as defined by the TVPS) are different. Although dyseidetic dyslexia results in characteristic coding patterns producing specific reading problems, it is probable that visual perceptual deficiencies contribute to learning problems that include general reading problems. Each condition would, therefore, require different forms of therapy. Limitations of this study and recommendations for future research are discussed.

Two methods for assessing accommodative facility were compared: the Computer Orthoptics Diagnostic Program and the standard Lens Flipper Method. In random fashion, 40 visually normal [modified clinical technique (MCT) screening] subjects, ages 10 to 18 years, were tested monocularly and binocularly on both methods. Scatter-plot comparisons of the data showed no apparent relation between the two methods, with correlation coefficients close to zero for both monocular (r = 0.0205) and binocular (r = 0.1180) results. In addition, the subject's diagnostic classification (pass or fail) was compared between the two methods. The kappa statistic indicated a low level of agreement between the two methods both monocularly and binocularly. These results suggest that the Computer Orthoptics' diagnostic test is not a valid method for diagnosing accommodative facility deficiencies.

For many years, corneal arcus has been documented as a normal, age-related change. Recent literature implies that corneal arcus is associated with elevated cholesterol, especially in the young, but that the association is not apparent in the elderly. This study demonstrates corneal arcus, regardless of age, as an indicator of elevated serum cholesterol, and as such, a sign of increased risk for cardiovascular disease.