Biomedical subjects

M Scheiman

Publications and source records attributed to M Scheiman.

At least 19 recordsLinked to original sources

PubMed2001

Tropicamide (1%): an effective cycloplegic agent for myopic children.

PURPOSE: To evaluate the cycloplegic effect of 1% tropicamide in myopic children and to determine whether its efficacy is associated with age, gender, iris color, ethnicity, magnitude of the refractive error, or latent error. METHODS: Four hundred sixty-nine children enrolled in the Correction of Myopia Evaluation Trial (COMET; a multicenter, randomized, double-masked clinical trial evaluating the rate of progression of juvenile-onset myopia in children wearing progressive-addition versus single-vision lenses) were given 1 drop of proparacaine in each eye followed 1 minute later by 1 drop of 1% tropicamide and then a second drop of 1% tropicamide 4 to 6 minutes later. Five accommodative responses to 20/100 letters located at 4 m and 33 cm were obtained in each eye with an autorefractor, 20 minutes after the second drop. Residual accommodation was calculated as the difference between the mean spherical equivalent responses obtained at the two distances. An examiner graded iris color, and ethnicity was reported by the children's parents or guardians. RESULTS: The mean residual accommodation was small: 0.38 +/- 0.41 diopters (D) in the right eye and 0.30 +/- 0.41 D in the left eye. Small but statistically significant differences in residual accommodation were associated with ethnicity, but not with any of the other factors. CONCLUSIONS: Tropicamide (1%) is an effective cycloplegic agent in myopic children.

Accommodation, Ocular↗

PubMed1999

Frequency of convergence insufficiency among fifth and sixth graders. The Convergence Insufficiency and Reading Study (CIRS) group.

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.

Accommodation, Ocular↗

PubMed1997

Irlen lenses do not improve accommodative accuracy at near.

The purpose of the experiment was to determine the influence of Irlen lenses on steady-state accommodation in successful users, as there is speculation that near accommodative dysfunction may be a factor in these patients. Monocular steady-state accommodation in six successful Irlen patients was assessed for near blur stimuli (2, 3, and 4 D) either with nonfiltered spectacle refractive correction or their spectrally broad-band filtered spectacle refractive correction. Accommodation was measured subjectively using a Hartinger coincidence optometer. There was no significant difference in mean level of accommodation between the two conditions. Additionally, there was a small but significant increase in accommodative variability with the filtered prescription. The use of Irlen correction did not have any positive effect on monocular steady-state accommodation at near.

Accommodation, Ocular↗

PubMed1996

Prevalence of vision and ocular disease conditions in a clinical pediatric population.

BACKGROUND: The purpose of this study was to fill a significant void in the ophthalmic literature by performing a large scale, comprehensive, prospective study of the prevalence of vision disorders and ocular pathology in a clinical pediatric population using well-defined diagnostic criteria. METHODS: A prospective study was performed on 2,023 consecutive patients between the ages of 6 months and 18 years presenting for an initial comprehensive examination at the Eye Institute of The Pennsylvania College of Optometry. There were 373 subjects between 6 months and 5 years, 11 months of age, and 1,650 subjects between 6 years and 18 years of age. RESULTS: The most important finding from this study is that other than refractive anomalies, the most common conditions optometrists are likely to encounter in a pediatric population are binocular vision and accommodative disorders. The prevalence of accommodative and binocular (strabismic and non-strabismic) vision disorders is 9.7 times greater than the prevalence of ocular disease in children 6 months to 5 years of age, and 8.5 times greater than the prevalence of ocular disease in children 6 to 18 years of age. CONCLUSIONS: The data from this study has great significance for clinicians, optometric educational institutions, health care planners, and administrators. This data suggests that other than refractive anomalies, the most prevalent conditions in the clinical pediatric population are binocular and accommodative disorders. Clinicians should use a minimum data base that includes assessments of accommodation and binocular vision that will allow them to detect conditions with the highest prevalence.

Adolescent↗

PubMed1996

Comparison of the effectiveness of a nondilated versus dilated fundus examination in the pediatric population.

BACKGROUND: A study was performed to compare the clinical effectiveness of a nondilated fundus examination to a dilated fundus examination. METHODS: The population consisted of 90 pediatric patients aged 5 to 16 years. Subjects were randomly selected from patients presenting for a routine eye examination at the Eye Institute of the Pennsylvania College of Optometry. Direct ophthalmoscopy was performed on the subjects before pupillary dilation while direct and binocular indirect ophthalmoscopy were performed post-dilation. RESULTS: Twenty-three patients (25.5 percent) had one or more posterior pole anomalies not detected by the nondilated pupil examination. A total of 30 posterior pole anomalies were not detected by the nondilated pupil examination. Forty-six patients (51 percent) had one or more peripheral anomalies not detected by the nondilated pupil examination. Sixty-nine total peripheral anomalies were not detected by the nondilated pupil examination. CONCLUSIONS: A dilated fundus examination provides a more effective clinical method for evaluating intraocular health in a pediatric population.

Adolescent↗

PubMed1996

Accommodative and binocular vision disorders associated with video display terminals: diagnosis and management issues.

BACKGROUND: With the rapid computerization of the workplace, school and home office, it is likely that a vast majority of Americans will be using computers for significant amounts of time in the near future. Research has demonstrated a high prevalence of accommodative and binocular vision disorders in symptomatic VDT users, which underscores the importance of the assessment and management of accommodation and binocular vision for patients working with computers. METHODS/RESULTS: This paper presents a simplified approach for the diagnosis and management of accommodative and binocular vision disorders in VDT users. The emphasis is on modifications of the traditional examination routine to make the assessment as sensitive as possible to the vision problems associated with VDT use. CONCLUSIONS: To meet the needs of symptomatic VDT users, optometrists must perform a comprehensive assessment of accommodation and binocular vision. The use of appropriate testing, when combined with attention to the environmental factors associated with VDT use, will enable optometrists to understand the reasons for symptoms and design an effective treatment program.

Accommodation, Ocular↗

PubMed1992

Binocular vision section.

The participants at the 1991 Meetings of the Section on Binocular Vision and Perception presented a substantial amount of valuable theoretical and clinical information. There was considerable and valuable interaction between the audience and panel, especially after the symposium concerned with new techniques and how to use them. The exchange of specialized knowledge through discussions at symposiums such as these represents one of the best features of Academy meetings. These symposiums reemphasize and remind us of the expertise of our Academy members in management of binocular vision anomalies.

Dyslexia↗

PubMed1992

Anisometropic amblyopia: is the patient ever too old to treat?

Amblyopia is an example of abnormal visual development that is clinically defined as a reduction of best corrected Snellen acuity to less than 6/9 (20/30) in one eye or a two-line difference between the two eyes, with no visible signs of eye disease. We describe a sequential management program for anisometropic amblyopia that consists of four steps: (1) the full refractive correction, (2) added lenses or prism when needed to improve alignment of the visual axes, (3) 2 to 5 h/day of direct occlusion, and (4) active vision therapy to develop monocular acuity and improve binocular visual function. We examined records of 19 patients over 6 years of age who had been treated using this sequential management philosophy. After 15.2 (+/- 7.7) weeks of treatment the Amblyopia Success Index (ASI) documented an average improvement in visual acuity of 92.1% +/- 8.1 with a range from a low of 75% by a 49-year-old patient to a maximum of 100% achieved by 42.1% of the patients (8 of 19). Patients who had completed therapy 1 or more years ago (N = 4) maintained their acuity improvement. From these results we conclude that following a sequential management plan for treatment of anisometropic amblyopia can yield substantial long-lasting improvement in visual acuity and binocular function for patients of any age.

Adolescent↗

PubMed1991

Stereoacuity development in young children.

An operant preferential looking (OPL) test with random dot stereo targets was used to gather developmental data on stereoacuity thresholds in 180 children between 18 and 65 months of age. Results indicated a steady improvement in stereoacuity with age from 250 sec arc in the youngest children tested to 60 sec arc in the oldest group of children. The greatest improvement in stereoacuity occurs at 30 months of age where mean values improve from 225 to 125 sec arc. This large change in stereo threshold appears to be attributable to the significantly higher variability in responses in the children under 30 months of age vs. the lower variability in responses in children over 30 months of age. The overall steady improvements in stereoacuity appear to be a result of the developmental changes in the variability of responses rather than actual neurophysiological changes within the visual system.

Age Factors↗

PubMed1990

The effectiveness of Irlen filters for improving reading performance: a pilot study.

The objectives of this pilot study were to investigate the effectiveness of Irlen filters for improving comfort and reading performance and to determine whether traditional optometric intervention would be effective in relieving the symptoms commonly reported by people seeking help through the use of Irlen filters. Thirty subjects were included in the study: 12 males and 18 females. The ages of the subjects ranged from 9 to 51 (mean = 23.6). They were randomly placed in either an Irlen filter treatment group (n = 11), a vision therapy treatment group (n = 11), or a control group (n = 8). Pre- and posttesting on all subjects included a vision evaluation, reading and intelligence testing, the Irlen scotopic sensitivity screening test, and a symptom questionnaire. Results revealed that subjects in both treatment groups were more comfortable after treatment, although only the vision therapy group showed improvement in vision functioning. The subjects in the Irlen filter group did not show any significant gains in reading rate, word recognition in context, or comprehension.

Adolescent↗

PubMed1990

Assessment of accommodative facility using MEM retinoscopy.

Subjective testing of accommodative facility can be difficult with young or nonverbal children, and children with learning problems. A new technique to objectively assess accommodative facility using monocular estimation method (MEM) retinoscopy is described. The objective technique was compared to a subjective assessment of accommodative facility, and the techniques were in agreement 86% of the time. Possible clinical usefulness of the objective procedure is discussed.

Accommodation, Ocular↗

PubMed1990

Vision characteristics of individuals identified as Irlen Filter candidates.

Individuals with "scotopic sensitivity syndrome" have been reported to have visual symptoms including eye strain, headaches, blurred vision, double vision and words moving on the page. This study was designed to investigate Irlen's claims that these symptoms are unrelated to vision anomalies. She suggests that the use of Irlen tinted lenses/filters relieves these symptoms and results in improved reading performance. Thirty nine subjects (age 10-49) were recruited by advertising for a study of Irlen Filters/Lenses. Before the Irlen screening all subjects received an optometric examination. The results of this study demonstrate that 95 percent of the subjects identified as candidates for Irlen Filters did have significant and readily identifiable vision anomalies. Fifty seven percent of the subjects had received vision care within the past year, yet testing revealed that 90 percent of these subjects had significant vision problems that had not been corrected.

Accommodation, Ocular↗

PubMed1989

Surgical success rates in infantile esotropia.

An extensive literature search covering the last 35 years was undertaken to retrieve all English language articles reporting results of surgical management of infantile esotropia. Only 27 of the 48 studies retrieved met the minimum criteria which we established for inclusion in our analysis. The success rate for achieving some level of binocular vision was 22% in 1286 patients, while the overall cosmetic success rate was 63% in 2113 patients. Newer surgical procedures appear to be more effective in achieving cosmetic success. Although controversy still exists about the optimal time for surgery, the most reasonable approach appears to be the concept of performing surgery as soon as an accurate determination can be made of the deviation and associated characteristics, and only after attention has been directed to any accommodative component and treatment of amblyopia. Although approximately 60% of patients referred for surgery can be expected to achieve cosmetic improvement after the first operation, the need for multiple surgery is common. There is a trend toward recurrence of the strabismus, and the need for short interval, long-term optometric follow-up is essential.

Esotropia↗

PubMed1989

A normative study of step vergence in elementary schoolchildren.

The purpose of this study was to develop normative data for step vergence testing in children age 6-12. Such data are not currently available for this age group. Base-in and base-out step vergence testing with a prism bar was performed on 386 elementary schoolchildren who had all passed a modified clinical technique (MCT) screening. A new polarized target was developed which enabled us to detect suppression, as well as diplopia or blur. The findings suggest significant differences from normative data previously reported for adults. Because the data for 6-year-olds were different from the rest of the group, we suggest that lower norms be used for this age group. This study provides expected findings for step vergence testing outside the phoropter, which can be used clinically for the assessment of disparity vergence ranges in young children.

Child↗

PubMed1989

Management of intermittent exotropia using a combination of vision therapy and surgery.

Vision therapy has been shown to provide higher success rates than surgery in the treatment of intermittent exotropia, but vision therapy is not successful in all cases. A case of intermittent exotropia is presented that illustrates the use of vision therapy in combination with surgery. Issues that should be considered when selecting this treatment option are discussed.

Adult↗

PubMed1988

Normative study of accommodative facility in elementary schoolchildren.

Although accommodative facility testing is used widely in the evaluation of accommodation in children, published normative data are not available for this age group. Current values being used are based upon studies of adult populations. In order to establish norms, 542 elementary schoolchildren were screened. Those that passed a specific set of criteria were included in the accommodative facility assessment. We used a new target and instructional set, which took into consideration the problems associated with subjective testing of young children. The results revealed lower mean accommodative facility values for both monocular and binocular accommodative facility than the values obtained previously from adult populations. These new findings can be used as a clinical guide to evaluate accommodative facility in young children.

Accommodation, Ocular↗

PubMed1987

Biofeedback training of visual acuity and myopia: a pilot study.

Biofeedback training of accommodation was performed with nine subjects using the Accommotrac Vision Trainer to attempt to improve visual acuity (VA) and reduce myopia. A single-subject research design was used. Improvements in VA were seen with some subjects, but it is not clear whether the improvements were due to the biofeedback training alone, or to a learning effect observed during repeated measurements of VA. There was no change in refractive error. Implications for future research are discussed.

Accommodation, Ocular↗

PubMed1987

Surgical success rates in acquired, comitant, partially accommodative and nonaccommodative esotropia.

An extensive literature search covering the last 35 years was undertaken to retrieve all English language articles reporting results of surgical management of acquired, comitant, nonaccommodative and partially accommodative esotropia. Thirty-nine studies were found, but only 15 met the minimum criteria which we established for inclusion in our analysis. The functional success rate was 15% in 1170 patients, while the overall cosmetic success rate was 43% in 1473 patients. Direct comparison to optometric studies is not possible since the criteria for success used in surgical studies are considerably different. The most prevalent complication is the need for reoperation as a result of consecutive exotropia. The data indicate that an end result of consecutive exotropia is almost as likely as a functional cure.

Accommodation, Ocular↗