Ординатура / Офтальмология / Английские материалы / Low Vision Aids_Chaudhry_2006
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Other Assistive Devices 79
Fig. 8.6: TVi classic with fixed magnification
Fig. 8.7: TVi prisma
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Fig. 8.8: CCTV systems from Telesensory
Fig. 8.9: Speech output automatic text reader
•Handheld cameras that interface with a standard TV set or other portable devices, such as head borne video displays or miniature flat panel displays
•Head mounted systems where the camera and LCD displays are combined in a single unit
•Self contained portable units, where the camera and screen are in single unit (these now include miniature LCD magnifiers that are very small and lightweight).
INDEPENDENT LIVING DEVICES (Figs 8.10 to 8.17)
Devices for daily living, like talking scales, talking glucometers, color identifiers, talking compasses, and a variety of other devices.
Other Assistive Devices 81
SOME INDEPENDENT LIVING AIDS
FOR VISUALLY IMPAIRED
Fig. 8.10: A talking mobile phone
Fig. 8.11: Parrot voice mate talking diary—A talking diary
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Fig. 8.12: The Leo Calculator—calculator’s scientific functions
Fig. 8.13: Talking alarm clock, watches
Other Assistive Devices 83
Fig. 8.14: Recreational items like: Large print playing cards, Braille dice
Fig. 8.15: Needle threader
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Fig. 8.16: Cooking devices like measuring cups, liquid alarm filler
Fig. 8.17: Health items like talking blood pressure meter, talking glucometers, talking thermometer
An ever-increasing number of “simple” technologic devices that provide greater accessibility for those with vision impairments have been appearing on the market, such use speech recognition to cell phones with talking alerts.
Who will Benefit?
When optical devices are difficult to use, assistive technology may allow the person to function more effectively.
Technology continues to improve, and in many cases, has also become less expensive. Ultimately, all of our patients will benefit from assistive technology in the future.
Before deciding for the device a brief history and detailed needs of the patient has to be evaluated. Basically, all devices are made to enhance the residual vision, but which device will depend on many factors.
Following are the considerations to be dealt with before prescribing the device (Figs 9.1 to 9.6).
1. Age of Onset of the Disease
Patients with congenital abnormalities or those born with visual disability are always the cooperative ones. They are willing to use almost all types of devices and value them. Patients with acquired visual disability are the difficult ones they need to be motivated and explained a lot before prescribing the device.
2. Eye Pathology
There signs and symptoms depend upon the eye pathology. Based on these the devices are selected and advised. This further depends upon the field defects, contrast and glare associated with the disorder. The progression of the disease is also a deciding factor in the type of device to be prescribed and will also consider the rehabilitation intervention for the patient.
3. Type of Field Defect
In addition to the type of disorder the effect of the individual’s eye pathology on the visual field will also affect the performance of the device. The field defects should be classified according to four categories (Faye’s classification): no field defect, central
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Fig. 9.1: Options-binocular telescope
Fig. 9.2: Options-handheld telescope
Selecting the Devices for Partially-Sighted 87
Fig. 9.3: Options-reading telescope
Fig. 9.4: Options-hand magnifier
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Fig. 9.5: Options-magnifying glasses
Fig. 9.6: Options-stand magnifier
field defect, peripheral field defect or combination of the above. Large central field defects or tubular fields will limit the use and benefit of the device. This has been further explained in detail in the following chapters.