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Alan R Morse,1,2 William H Seiple1,3 1Lighthouse Guild, New York, NY, USA; 2Harkness Eye Institute, Columbia University, New York, NY, USA; 3Department of Ophthalmology, New York University School of Medicine, New York, NY, USACorrespondence: Alan R Morse; William H SeipleLighthouse Guild, 250 West 64th Street, New York, NY 10023, USATel +1 212 769 6215Email armorse@lighthouseguild.org; Wseiple@lighthouseguild.orgAbstract: Adherence to medication treatment protocols and active participation by individuals in their medical care are important for all patients, but especially for those with chronic conditions such as vision loss. Adherence is crucial for decreasing avoidable vision loss. Failure to take medications as prescribed and keep scheduled appointments reduces treatment effectiveness, increases complications and results in poorer outcomes. Reasons for nonadherence vary by diagnosis and include not understanding the importance of adherence, low health literacy, lack of adequate self-efficacy, low level of activation and behavioral issues including depression. Patients may lack information about their condition and its prognosis, available treatment alternatives, and other essential information such as how to monitor their eye condition, what to do if vision deteriorates and how to get needed community-based help. Each of these factors impedes patients’ ability to engage with their physician and participate in their own care. The ability of individuals with vision loss to actively and effectively manage their health care, ie, activation, has been understudied. When patients are involved with their own care, their care experience, and most importantly, their outcomes, are improved. Identifying antecedents of adherence may help provide disease- and patient-specific pathways to reduce avoidable vision loss.Keywords: avoidable vision loss, adherence, activation, engagement, patient activation, patient engagement, AMD, diabetic eye disease, glaucoma

PurposeTo establish normative values for macular light sensitivity and to determine the intrasession fluctuation of perimetric responses using the OPKO/OTI microperimeter.MethodsA total of 32 visually normal subjects participated in the study. A standardized grid pattern was used for testing, which consisted of 28 points arranged concentrically in three circles that occupied an area of 11° (in diameter) within the central macula. Each subject participated in at least two tests. Parameters evaluated included: overall mean macular sensitivity for test 1 and 2, overall difference in mean macular sensitivity between tests, and the mean sensitivity for each circle. The relationship between sensitivity and age was also examined.ResultsThe overall median sensitivity for test 1 was 16.8 decibels (dB) and for test 2 was 16.9 dB. The median sensitivities for test 1 and test 2 were not significantly different (P=0.72). The mean intrasession sensitivity difference was 0.13 dB. The variability of the sensitivity difference between tests decreased as mean sensitivity increased. The sensitivity values averaged across the two tests for inner, middle, and outer circles ranged from 14.3 to 18.8 dB (median value of 16.9 dB), 13.8-18.3 dB (median value of 17.2 dB), and 11.3-18.3 dB (median value of 16.6 dB), respectively. Linear regression analysis showed a 0.5 dB sensitivity loss for each decade of life.ConclusionWe documented a narrow range of intrasession fluctuation using the OPKO/OTI microperimeter. The establishment of normative sensitivity values will facilitate monitoring the loss of macular visual function in patients with retinal disease. [ABSTRACT FROM AUTHOR]

Multidimensional psychophysical and electrophysical maps of the central retina are essential for assessing the functioning of the diseased retina. In this study, grating acuity, contrast sensitivity, duration for letter identification, multifocal electroretinograms, and Humphrey visual field thresholds were measured at equivalent positions throughout the central 20°. We found that the rates of sensitivity loss were not equivalent for all psychophysical measures. The rate of loss in the duration required for letter identification as a function of eccentricity was the steepest, followed by acuity and contrast sensitivity. The rate of loss in luminance sensitivity as measured in the Humphrey visual field was the shallowest. The pattern of losses also varied across meridians. Specifically, the rate of loss as a function of eccentricity was highest in the vertical meridian and lowest in the horizontal meridian. These maps and the correlations among measures as a function of retinal position serve as a baseline so that we can examine disease effects throughout the retina. In addition, the development of vision rehabilitation programs focused on eccentric viewing training should consider the differential sensitivities of the peripheral retina. [ABSTRACT FROM AUTHOR]

PURPOSE: 1) To evaluate a vision rehabilitation program aimed at training persons with central vision loss to use a bioptic telescope for improving life skills, including driving and 2) to compare the outcomes of subjects who are given bioptic telescopes and training, with subjects who are prescribed telescopic lenses without training. METHODS: Twenty-five subjects ranging in age from 16 to 78 years were included in the study. Each subject was randomized to one of three groups: Group 1 received bioptic telescopes and training during the first approximately 3-month-long period of the approximately 6-month-long study; Group 2 received lenses and training during the second approximately 3-month-long period of the study; and Group 3 received the lenses for approximately 3 months without any training. An assessment battery consisting of clinical vision tests, functional tasks evaluated by an orientation and mobility specialist, driving skills evaluated by a kinesiotherapist specializing in driver's education, and psychophysical measures was administered to Groups 1 and 2 at baseline, and at approximately 3 and 6 months, and to Group 3 at baseline and at approximately 3 months. The tasks were categorized into 6 major functional categories: Recognition, Mobility, Peripheral Identification, Scanning, Tracking, and Visual Memory. Training consisted of 5 weeks of laboratory-based training focusing on skills within these 6 categories, and 8 weeks of on-road driving training. RESULTS: There was significant improvement in all task categories with use of the telescopes. There was improvement in all task groups with training, though a significant difference between the trained and untrained groups existed only in the Recognition, Peripheral Identification, and Scanning Categories, but not in Mobility, Tracking, or Visual Memory. When the tasks involving driving-related skills were analyzed separately, training also had a significant effect. CONCLUSION: There was significant improvement in visual skills with the use of a bioptic telescope. This improvement was greater with training in the use of the lenses in a number of visual skills categories including driving-related skills. [ABSTRACT FROM AUTHOR]

Sensitivity losses in patients with retinitis pigmentosa (RP) have been attributed to a decrease in photopigment density, to a reduction in the number of photoreceptors, and also to a change in temporal response properties of the receptors. The sensitivity losses in patients with macular degeneration have also been attributed to a loss of photoreceptors. To test these explanations for sensitivity loss we obtained electrophysiological and psychophysical temporal modulation transfer functions (MTFs) on normal subjects in response to varying stimulus luminances and retinal loci. These stimulus manipulations did not duplicate the changes observed in the temporal MTFs of patients. The temporal response properties of the receptors were tested electrophysiologically by manipulating stimulus presentation interval. The results provided evidence for sensitivity losses in RP patients being due to alterations in the temporal response properties of the receptors. [ABSTRACT FROM PUBLISHER]

Focal electroretinograms (FERG), pattern electroretinograms (PERG), and visual evoked potentials (VEP) were studied in a group of 30 aphakic patients with cystoid macular oedema (ACME). When compared with a control group of age-matched aphakics, 35% of patients were found to have abnormal FERG responses and 53%--over half of whom had normal FERG responses--showed abnormal PERG amplitudes. Although most of the patients had associated optic disc leakage, VEP latencies were normal in 26 out of 30. These results may explain the more severe visual loss seen in some ACME patients where the ophthalmologically visible retinal changes do not seem sufficient to explain such reduction in vision. [ABSTRACT FROM PUBLISHER]

This study identifies clinical vision measures or retinal structural measures associated with the driving performance of diabetic retinopathy patients. Twenty-five licensed drivers with diabetic retinopathy (median age, 53 years; range, 34-72 years) completed clinical tests (visual acuity, letter contrast sensitivity, and Humphrey 30-2 visual fields) and structural examinations (retinal thickness analysis and fundus photograph grading of retinopathy and laser scarring). Driving performance was assessed with an interactive driving simulator and a driving history questionnaire. Increased retinal thickness was significantly correlated with a higher frequency of simulator accidents and near accidents. Laser scar grades significantly correlated with steeper brake-response slopes, increased brake-pressure standard deviation (SD), and longer response times. Subjects with focal laser scars had significantly higher average brake-pedal pressure and brake-pressure SD than subjects without focal laser scars. Retinal thickness and laser scarring correlated with driving simulator performance in subjects with diabetic retinopathy. [ABSTRACT FROM AUTHOR]

This article describes the experimental protocol used to instruct fifteen patients with peripheral visual field loss due to retinitis pigmentosa, choroideremia, or Usher's syndrome Type II how to effectively use bioptic amorphic lenses. The factors that contributed to the successful use of these lenses, as well as difficulties the patients encountered, are discussed. The results of the study (published in detail in Szlyk et al. Use of bioptic amorphic lenses to expand the visual field in patients with peripheral loss. Optom Vis Sci 1998;75:518-24) indicate that bioptic amorphic lenses, when combined with a comprehensive training program, can expand visual function in the areas of peripheral detection, recognition, scanning, tracking, visual memory, and mobility. [ABSTRACT FROM AUTHOR]