Kimberly S. Merrill

Reading acuity in albinism: Evaluation with MNREAD charts

INTRODUCTION The MNREAD reading acuity (RA) charts use continuous-text reading to measure (1) RA, ie, the smallest size of print that the patient can resolve; (2) maximum reading speed (MRS); and (3) critical print size (CPS), ie, the smallest print that the patient can read with maximum speed. This project used the MNREAD charts to evaluate reading performance in children and adults with albinism to determine the smallest print size recommended to facilitate effortless reading. METHODS A total of 63 subjects with albinism were administered the MNREAD test to determine the critical print size for effortless reading. The subjects read continuous, high-contrast text print until they could no longer discern the words. The MRS and CPS were determined with the MNREAD protocol. Presence or absence of nystagmus and strabismus was recorded. Distance visual acuity was measured with ETDRS charts. RESULTS The sample included 25 male and 38 female subjects with a median age of 16 years. Median MRS was 150 words per minute. The mean CPS was 0.84 logMAR, notably larger than the mean RA of 0.53 logMAR. CONCLUSIONS The MNREAD acuity charts can be used to determine functional reading ability and critical print size for effortless reading in individuals with albinism. The amount of enlargement in print size can be used in educational and vocational recommendations to facilitate reading.

Evaluation of vision-specific quality-of-life in albinism

INTRODUCTION Human albinism is a genetic condition associated with visual impairment that affects many aspects of daily life. Office measurements of visual acuity do not necessarily reflect daily visual function and health status. This study used the National Eye Institute Visual Function Questionnaire (NEI-VFQ) to determine the effect of albinism-associated ophthalmopathy on quality of life (QOL). METHODS We administered the NEI-VFQ, which consists of 25 questions about QOL (VFQ-25) and 14 questions about well-being (VFQ-39), to 44 consenting participants with albinism older than the age of 18 years. RESULTS Nineteen male and 25 female subjects completed the study. Median age was 30.5 years (range, 18-79 years). Mean best-corrected visual acuity was 20/83 (range, 20/20 to 20/320). Forty-eight percent reported that they were currently able to drive with their condition. Participants perceived midscale problems with their general vision (median subscale score 60.0). Visual acuity correlated moderately with overall NEI-VFQ composite scores (r(s) = 0.40, p = 0.01 for VFQ-25 and r(s) = 0.36, p = 0.02 for VFQ-39). Most notable impairment was recorded for distance acuity, vision-specific mental health, and vision-specific role difficulties (VFQ-39 median subscale scores 66.7, 70.0, and 75.0, respectively). Differences by sex were insignificant. Greater ceiling effects were noted for the VFQ-25 than for the VFQ-39. CONCLUSIONS The NEI-VFQ-39 is a method to evaluate self-reported effects of vision-related QOL in albinism and may be used as a baseline for evaluating outcomes in interventional studies in these patients.

DVD--a conceptual, clinical, and surgical overview.

Dissociated vertical deviation (DVD) is a slow, disconjugate hypertropic deviation of a nonfixating eye. It is usually bilateral, asymmetrical, and often associated with congenital esotropia. The deviating eye elevates, abducts, and excyclotorts. This type of strabismus is often variable, making measurement and clinical quantification difficult. Specific knowledge of the mechanisms and characteristics of the dissociated deviation are required for proper assessment and effective treatment. There is currently no consensus on the mechanisms and pathophysiology of DVD. In this workshop, participants discuss the characteristics and most current methods for assessing and quantifying the deviation and explore the potential etiologies, clinical characteristics, and indications for surgical intervention and nonsurgical management of DVD.

Positive Angle Kappa: A Possible Sign of Aniridia

Introduction and Purpose Aniridia is a panocular disorder with variable expressivity, caused by PAX6 mutations. Foveal hypoplasia and nystagmus occur in both aniridia and albinism. Individuals with albinism have a moderately positive angle kappa. This study evaluates the angle kappa in individuals with aniridia. Patients and Method We performed a retrospective chart review of recorded angle kappa for individuals with aniridia. In addition, we prospectively examined the monocular corneal light reflex in each eye of patients with congenital aniridia and central fixation. We recorded other ocular characteristics and the results of gene testing. Patients with eccentric fixation or corneal surgery were excluded, as were patients with retinal abnormalities that might have influenced the angle kappa. Results We included sixteen individuals with congenital aniridia and found that all had a positive angle kappa. Two patients underwent pattern visual evoked potential (VEP) testing with monocular stimulation and were found to have a reversal of polarity, indicating misrouting of the retino-striate fibers. Conclusion The phenotype of aniridia is variable. However, a positive angle kappa may be considered to be a frequent clinical feature of aniridia.

Red Flags in the Assessment of Adult Ophthalmoplegia

ABSTRACT Acquired ophthalmoplegia can represent a harbinger of vision and life-threatening disease. Recognition of select clinical “red flags” on history or examination can facilitate early diagnosis. This article reviews relevant clinical pearls for the detection of dire causes of acquired ophthalmoplegia in adults including myasthenia gravis, carotid cavernous fistula, giant cell arteritis, and thiamine deficiency. Prompt treatment of all of these disorders can either reverse or halt the progression of visual manifestations.