Two night vision aids are commercially available to help individuals who have diseases that cause night blindness. The ITT Night Vision Aid (NVA) is a light amplification device; the Wide Angle Mobility Light (WAML) is a wide beam flashlight. The effectiveness of both instruments in helping night-blind, field-restricted subjects to ...

The Night Vision Aid is a photomultiplier device developed by International Telephone and Telegraph Co. (ITT) and the Retinitis Pigmentosa Foundation as a mobility aid for those with night blindness. The purpose of this study was to measure visual acuity with and without the Night Vision Aid at a variety ...

The use of Contrast Sensitivity Functions (CSF's) in vision evaluation has been explored for several years. Although theoretically superior to Snellen acuity and similar measures, the use of CSF is not widespread. A review of some of the clinical conditions in which CSF's have been used is followed by a ...

We constructed a low-vision aid for a 61-year-old patient who had familial macular degeneration and a visual acuity of 20/300. The aid consisted of a spectacle lens incorporating his distance prescription as the carrier, a high-plus bifocal reading addition, and the high-minus ocular lens of a Galilean telescope of variable ...

Frequently, patients with macular lesions and others who are visually handicapped do not receive adequate low vision care by ophthalmologists if a routine trial of low vision aids has no gratifying results. This paper describes for the first time a technique in which functional vision was achieved with the aid ...

The problem of UV vision in vertebrates is briefly discussed in its historical context. For example, UV vision has been demonstrated in some birds by several authors. Hence the reflectances of plumage, petals of bird-pollinated flowers and of berries in the near UV may play an important rôle within the ...

Corneal arcus presents many puzzling features. The correlation between its incidence and serum lipid levels is poor and, using immunoelectrophoresis, we have only been able to identify low-density lipoprotein inconsistently in corneae containing this deposition. Infrared thermography has shown us that arcus commences in the warmest regions of the cornea. ...

Low vision aids used in the spectacle plane may be either plus lenses or telescopes focused for near. The plus lens has a shorter working distance than a near point telescope of the same equivalent power. A relationship between the anterior focal length (fv) of the near point telescope and ...

Individuals with disorders such as retinitis pigmentosa or severe glaucoma often have difficulty ambulating at night, not only because they have lost rod vision, but because flashlights do not help. The problem is that ordinary flashlights produce a very narrow beam of light (only about 3 degrees) which is hard ...

Retinitis pigmentosa was considered unfavorable for low vision corrections before it was recognized that the term retinitis pigmentosa as frequently used referred to a group of disease entities including Leber's congenital amaurosis, centro-peripheral dystrophy, typical retinitis pigmentosa and Usher's syndrome. The success rate for use of optical aids was Leber's ...

An unusual low-vision remedy was encountered in which a simple dime-store marble was used in near vision tasks. Although the marble was found satisfactory as a low-vision aid, the patient could be better assisted with a commercially available magnifier of lesser dioptric power. This case serves to demonstrate a patient's ...

Weight is a problem in retention of large skin-textured maxillofacial prostheses. The purpose of this investigation was to test the feasibility of mixing foam RTV silicone rubber with conventional RTV silicone rubber to obtain a light-weight material. Various mixtures of foam and conventional silicone rubber were formulated and tested for ...

Although it is apparent that a successful substitute for vision will not be available for at least two or three decades, the past twenty five years of research is now bearing fruit. Within the next few years several high-technology devices will solve the problems of mobility and reading. Besides this ...

The aging (presbyopic) pilot has difficulty with near vision which can be a serious problem in the cockpit because of the complexity and uniqueness of his visual tasks. Numerous individual studies have been reported, but the aviation industry and vision care professionals do not have available to them a set ...

The aged have many problems peculiar to their longevity. One is the need for a visual correction. Often the prescription is high in power and needs special consideration, especially for low vision and aphakie patients. Always the materials supplied must provide comfort and whenever possible, cosmesis. This paper covers these ...