Roger W. Cummings

Scanning characters and reading with a central scotoma.

Among the patients we tested, most of those who had lost normal macular function developed extrafoveal retinal loci which resulted in strongly preferred viewing angles for steady fixation. These patients used these extrafoveal retinal loci to scan lines of characters in patterns similar to patients with normal macular function. Although the scanning speed of these patients was adversely affected by their large size scotomas, their reading accuracy was not necessarily reduced. The assessment of scanning and reading performance in this population requires careful measurement of the visual skills involved in reading.

Saccade control without a fovea

Prior research has suggested that two types of fast eye movements (FEMs) can be distinguished behaviorally. Foveating saccades respond to salient peripheral targets by directing the target image to the fovea. Non-foveating saccades include other FEMs such as nystagmus quick phase, saccades without visual stimuli and visually-directed saccades that direct target images to eccentric retina. Foveating saccades have a shorter initiation latency and are faster than non-foveating saccades. Following adaptation to central scotoma, patients tend to use preferred retinal loci for fixation (PRL). If PRL acquire the foveal characteristic of a retino-motor center then visually guided saccades would acquire the properties of foveating saccades. Using an objectively-calibrated 2-dimensional search coil, we measured saccades in response to salient, unpredictable targets. The saccades of normal observers were compared to the saccades of patients with long-standing macular scotomas. Although the saccades of patients consistently directed images to PRL, the saccades still had the latency and dynamic characteristics of non-foveating saccades. Moreover, the non-foveating saccades of patients were found to be less accurate than foveating saccades, showing a range effect (larger saccades undershoot with greater error than do smaller saccades). Apparently, patients with macular scotoma suppress rather than adapt a foveating saccade mechanism.

Economic evaluation of blind rehabilitation for veterans with macular diseases in the Department of Veterans Affairs.

Purpose: The Department of Veterans Affairs (VA) Low Vision Intervention Trial (LOVIT) developed an outpatient low-vision programme for patients with macular diseases providing low-vision rehabilitation comparable to VA inpatient blind rehabilitation centres (BRCs). This programme targets veterans who do not need or chose not to participate in a comprehensive inpatient blind rehabilitation programme. We examined costs and consequences using veterans in LOVIT and comparable veterans in an inpatient BRC. Methods: We compared costs and consequences between treatment patients who participated in LOVIT, a two-site randomized clinical trial, and a sample of comparable patients who received treatment at a VA inpatient BRC. We measured consequences as the change in functional visual ability from baseline to follow-up (LOVIT: 4 months after randomization; BRC: 3 months after discharge) using the VA Low Vision Visual Functioning Questionnaire (VA LV VFQ-48). Results: There were 55 LOVIT and 121 BRC patients for our analyses. Average costs were

The Veterans Affairs Low Vision Intervention Trial (LOVIT): Design and Methodology

38,627.3 higher for BRC patients (

An improved electrode for electroretinography: design and standardization.

5,054.4 ±

Measurement of Central Fields Following Macular Degeneration

404.7 SD for LOVIT vs.

An accessory fill-in flash for the Nikon photo-slit lamp.

43,681.7 ±

Recording monocular VEPs under binocular conditions.

8,853.6 SD for BRC, p < 0.0001). Thus, the BRC cost

Successful Outcomes from a Structured Curriculum Used in the Veterans Affairs Low Vision Intervention Trial.

38,627.3 per patient more than the LOVIT programme (95% CI:

Article 15: A Randomized Controlled Trial to Evaluate Outcomes of Outpatient Low-Vision Rehabilitation

17,414 to