Biomedical subjects

M Scheiman

Publications and source records attributed to M Scheiman.

15 recordsLinked to original sources

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↗

PubMed1986

Heterotopia of the macula (ectopic macula): an unusual presentation.

Heterotopia of the macula is a condition in which the macula is displaced markedly from its normal position. Only 40 cases have been reported in the literature. Of those cases more than 90% have occurred in patients presenting with an apparent exotropia (macula displaced temporally), a large positive angle lambda, and an actual esotropia. We report a unique case of heterotopia of the macula in which the patient presented with an apparent esotropia and a large negative angle lambda. This is the only reported case of ectopic macula in which the macula has been dragged nasally toward the disc in association with a suspected retinopathy of prematurity. There have been three other cases of heterotopia of the macula in which the macula was displaced nasally, but these were associated with chorioretinitis.

Amblyopia↗

PubMed1986

Divergence insufficiency: characteristics, diagnosis, and treatment.

Although the entity of divergence insufficiency was described as early as 1886 by Duane, it has received relatively little attention in the literature. Patients presenting with a greater eso deviation at distance than at near, a concomitant deviation, and diplopia pose a challenging and critical diagnostic and therapeutic puzzle for the clinician. Divergence insufficiency, a benign condition, must be differentiated from divergence paralysis and sixth nerve palsy, two conditions that present with somewhat similar findings yet have underlying etiologies of a serious nature. This paper reviews the literature and clarifies the etiology, diagnosis, and treatment of divergence insufficiency and related conditions.

Convergence, Ocular↗

PubMed1986

The effect of protective sports eyewear on peripheral visual field and a peripheral visual performance task.

Seven different types of protective sports eyewear were tested to determine whether peripheral awareness as measured with a visual performance task were affected. Goldmann perimetry and the Wayne Saccadic Fixator with Stik-Up attachments were utilized in a repeated measures research design. The sports glasses did restrict visual field, but no one pair of glasses were least restrictive. The restrictions did not translate into significant differences on the performance task. Peripheral visual factors should be taken into account when prescribing protective sports eyewear. The importance of proper eye protection in sports is also discussed.

Adult↗