Primary Outcome Measures:
- Participants will be given the following assessment tests at 3 different times during the assessment (at baseline, after 4 weeks, post-training): daily performance measures, reading measures, and questionnaires. [ Time Frame: Pre-training, 4 weeks after training, post-training ] [ Designated as safety issue: No ]
Age-related macular degeneration (AMD) is currently among the top three leading causes of central vision loss in veterans (Chomsky et al., 1995) and is the most prevalent cause of blindness among veterans (37.2%, Quillen & Henry, 2000). The loss of central vision associated with these diseases has a profound impact on the quality of life to those affected, with many suffering depression. It is devastating to no longer be able to read a newspaper or recognize facial expressions. The use of preferred retinal locations (PRLs) to compensate for diseased foveae has offered hope to these patients in regaining some function. The investigators have developed a protocol that includes training in two major visual skills areas:
- Visual awareness and eccentric viewing; and
- Reading practice with sequentially lexical information
Module 1 focuses on making the patient aware of better vision at an eccentric location relative to degraded vision at the diseased fovea. Module 2 is focused on reading practice without eye movements. These program curriculums and preliminary results are provided in the present proposal. The primary aim of this proposal is to quantitatively assess the relative effectiveness for improving reading and to establish the minimum training time need for skill improvement. One hundred and twenty patients with macular disease who are already using a PRL and similar in visual characteristics (e.g., visual acuity, contrast sensitivity, size of scotoma, duration of the disease) will be included the study. All patients will be trained with both modules using a repeated measures-completely counterbalanced - design to control for training order effects. In addition, all patients will be assessed using the same outcome measures of reading (using MNRead Acuity Charts and the View Sentences Test). The performance of the patients on the outcomes battery post-training will be compared to their pre-training performance on the same battery. Questionnaires (the Veterans Administration Low Vision Visual Functioning Questionnaire, CES-D, Short Form-36, and Adaptation to Vision Loss Scale) will also be administered to assess perceived abilities to perform everyday tasks, adaptation to vision loss, moods, and general health. In addition, patients will also be assessed on the exercises practiced during the module at the end of each daily training session to determine exactly when in the training protocol an improvement in performance on the exercises being trained has occurred. These daily performance measures provide for a finer scale for detecting performance changes. Statistical analyses will be conducted to answer the following questions:
- Does a combination of eccentric viewing awareness and oculomotor training produce significant improvements in reading rate?
- Which exercises are most effective in training the visual skills associated with reading and at what point during the course of training do the patients reach asymptotic performance?
- How do co-factors such as age, PRL size and location, and cognitive capabilities relate to training outcomes?
Advancements are being made in the area of retinal cell transplantation, gene therapy, and retinal prosthetics. When these techniques become part of the standard clinical care, it is likely that all the patients will require vision rehabilitation techniques to help them make sense of their potentially fragmented percepts. This research offers an evaluation of relative successes of the components of reading rehabilitation and will lead to the design of an efficient and effective composite training strategy.