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Full-field reversed 1.3X telescopes were used in the treatment of a 63-year-old male retinitis pigmentosa (R.P.) patient with a 5 degree central field. The patient was highly motivated to "expand" his visual field. He was trained intensively with 1.3X, 1.7X, and 2,2X reversed telescopes prior to prescribing. Evaluations by the Orientation and Mobility staff indicated significant improvements in his functioning with the devices. The reversed telescopes expanded his field to approximately 14 degrees. Patient has been reevaluated after using the aid at home and remains enthusiastic about his successful use of the aid. This case is notable in that binocular, low-power, full-field, reversed telescopes are being used successfully for mobility, eating, and other tasks.

Data from 96 veterans who had been using a closed circuit television (CCTV) for at least 2 years are presented. Most patients (87%) reported continuing use of the CCTV and demonstrated their proficiency in its use. Fifty percent of all patients used an optical aid, as well as a CCTV for near work. These patients did not differ on mean reading speeds for either type of aid, but the CCTV did provide significantly longer reading durations. Neither near nor far visual acuity measures were correlated with performance variables. Linear magnification, working distance, and effective magnification on the CCTV appeared to interact to influence CCTV reading speed. The data have clear implications for clinical practice.

Reading speed and duration were measured for 24 low vision subjects, 12 learning to use closed circuit television and 12 learning to use optical aids. Reading speed and duration increased for both groups during 10 days of training and practice. Improvement occurred by steplike increases and plateaus. Visual acuity was not correlated with either performance measure; reading speed on the initial day of training was correlated with reading speed on the last day. The results have implications for both the prescription of aids and the training of low-vision patients.

Thirty-six subjects completed questionnaires on their experiences wearing the CPF 550 lenses. Twenty-six subjects [21 with retinitis pigmentosa (RP)] were users of the 550's and 10 subjects (6 with RP) were nonusers who had rejected the 550's after a trial period. Subjects were asked about such factors as effects on adaptation time, ocular comfort, visual functioning, acceptability of tint strength in various lighting conditions, cosmetic appearance, effects of weather, and replacement intent. Users reported reduced adaptation time in changes of illumination, increased ocular comfort, improved visual functioning with the exception of poor color discrimination, and cosmetic acceptability. Satisfaction with tint strength varied with degree of illumination; usefulness in different types of weather also varied depending on the condition. Nonusers' responses were mixed; they were less likely to report improvements with the CPF 550 lenses compared to the users' group.

Confusion and misconception characterize the designation of near visual acuities because of the numerous systems in use. Most of these systems do not lend themselves to accurate or easy usage or to comparison with other test distances. Use of the M system, with the actual test distances recorded in meters, is suggested as a simplified system for standardization.

Macular degeneration results in more new cases of legal blindness in the United States than any other disease and accounts for over 165,000 first visits to physicians each year. Magnification, illumination control, and eccentric viewing training are the only documented, effective vision rehabilitation techniques known. Magnification has been used for decades, control of illumination has had a known effect for many years, and eccentric viewing training has been systematically used for less than 10 years. These techniques, although having demonstrated efficacy, require extensive individual patient training and a considerable investment of professional training time for optimum results. More recently developed techniques use prism correction for near and distance viewing or scanning laser ophthalmoscopy for training. Current knowledge of peripheral retinal function offers new avenues of research to improve upon current rehabilitation techniques. Computer technology also offers the hope of developing easily used, cost-effective materials and equipment to train the patient to use the peripheral retina in place of the damaged/diseased macula. In this paper, we examine current and emerging rehabilitation techniques and highlight some areas of research that hold promise of improving rehabilitation practices for patients having central visual field losses.