Site Loader

Age-Related Macular Degeneration (ARMD or commonly known as AMD) is the most common cause of vision loss in the developed countries. The condition is commonly occurred in people over 50 years old and it is estimated to have 1 in every 10 people over the age of 65 experiencing some degree of ARMD. ARMD only affect the central vision, which means it will not cause complete blindness as it do not affect the peripheral vision. There is various types of optical aids created to assist the ARMD’s patient to make the most of their remaining vision to fulfill their daily tasks easily such as hand magnifier, stand magnifier, spectacle mounted magnifier, CCTV system and etc. However, one who had ARMD will need few types of the optical aids for difference usage in completing their daily tasks. There is no one type of optical aid that can fit for all and the selection of optical aids will have to base on certain condition of the articular patient. For instance, a patient with macular degeneration achieves N12 binocularly @ 25cm with reading glasses of +4.00DS R & L. They will need CCTV system for doing crosswords assumed to be in N6 font.The condition of age-related macular degeneration happens when the macula – the part of the eye that is responsible for central vision stop function as effectively as it used to be. According to NHS Choices (2015), ARMD is a painless eye condition which cause one to lose central vision, generally in both eyes. Central vision is what a person will see when they focus straight ahead. People who suffer from macular degeneration will notice their central vision becomes progressively blurred. They will find reading become difficult and colours appear as less vibrant, along with some symptoms such as black shadows in vision, or straight line becomes wavy, and etc. It will then affect their ability to read, drive, recognize a face and perform any other task that requires seeing in fine details but it will not cause totally blind. This loss of vision are normally happens gradually over time. Yet, it happens rapidly sometimes to certain people. The exact cause of macular degeneration isn’t known, but the condition develops as the eye ages. Although advancing age is the greatest risk factor associated with the development of ARMD, environmental and lifestyle factors may significantly affect individual risk (Chen, Bedell, & Zhang, 2010). Family history and genetics are also the high risk factor that increases the chance of suffering from macular degeneration.There is various types of optical aids that served the purposes to improve the readability of ARMD’s patient. According to Macular Society (n.d.), “all macular diseases affect central vision and do not cause complete sight loss, there is always some peripheral vision remaining”. As macular degeneration mainly affect the central part of vision, magnifier is commonly used for the patient to read with their remained proper vision and peripheral vision. Magnifier magnify and increase the size of objects or texts to allow the presence of a bigger visual field for better viewing. The magnify process is done by the convex lenses that refract and bend the light rays. The convex lenses converge the light rays and create a virtual image on eyes’ retinas. That virtual image on the retinas appears larger than the real object due to principles of geometry. The actual amount of magnification needed will vary according to the person’s visual needs, environment, and the low vision device chosen (Gilbert & Van Dijk, 2012). Due to the condition of ARMD is difference to every patient, the power of magnification for the magnifier given to every patients have to be calculate and prescribe attentively. The magnification power can be calculated by the equation of actual near visual acuity divided by desired near visual acuity. In this case, the prescription for the patient was achieved N12 binocularly @25cm with reading glasses of +4.00DS for both eyes. Magnification requires for the patient to do crosswords with N6 font will be 2X.There’s currently no cure for either type of age-related macular degeneration, although vision aids may help. Since the magnification required for the patient is not too strong, there is a variety of magnifying device or magnifier can assist the patient to do a crosswords. Its include hand held magnifier, stand magnifier, spectacle mounted magnifier, and closed circuit television system (CCTV). Hand held magnifier, unsurprisingly, is a device that needs to be positioned and supported by user’s hand without artificial support. The magnification of hand held magnifier remains constant regardless of the eye-to-magnifier distance, providing the object is placed at the anterior focal point. The patient needs to wear their usual reading glasses when using the hand held magnifier, hold and place flat on the reading task. Then, raise the magnifier slowly away from the task until getting the desired vision. This handy device is portable and lightweight which make it easy to keep and bring outdoor. It comes in a variety of sizes, shapes, prices and can be prescribed with magnification power from 2X to 100X. However, it is not intend for long period use as it it tiring to hold it and maintain in focus. It also require steady hands and good motor control to hold steady, thus it is not suitable for the patient who has arthritis or Parkinson. In other hand, the simplest device for reading is the stand magnifier. Stand magnifier have a lens mounted on the stand, this type of magnifier is automatically in focus for reading when being placed on the flat surface page. The patient needs to move the magnifier across the page to read. Stand magnifier is inexpensive and easy to use. It is a good choice for people with tremors, arthritis or Parkinson as the stand magnifier is directly rest on the page. It can be in fixed or adjustable focus based on personal preference. Most of the stand magnifier are come with built in illumination to provide excellent illumination and available in a wide range of power. Aside from all the mentioned advantages, stand magnifier have a little downside due to the smaller field of view. It need to view in close reading distance, thus the fixed reading posture is uncomfortable for the patient when reading in longer periods.Moreover, spectacle mounted magnifier is also a helpful optical aid for ARMD’s patient. Spectacle mounted magnifiers can be attached onto your spectacle frame or worn independently in a full frame design. This clip-on magnifier range are available with a binocular lens for lower magnification versions and monocular lens for the higher magnification versions. The greatest advantage for this type of magnifier is that, patient can leaves both hands free to do other tasks. It also provide a wider field of view than other type of magnifier so one can read more line of words at a time to ensure greater reading speed. Despite this, it is bulky to wear and the weight may cause the spectacle to slide down the nose bridge. Patient also need to hold the reading material closer in order to get in focus. The reading distance is exactly the opposite with the magnification power. The stronger the magnification power, the shorter reading distance needed. Care should be taken whilst wearing spectacle mounted magnifiers to avoid walking around as disorientation could occur with the restricted field of view effecting depth perception.Furthermore, ARMD’s patient can choose an electronic desktop magnifier to assist them in reading, writing, and doing a variety of everyday living tasks. The electronic desktop magnifier is normally referred as closed circuit television system (CCTV). CCTV consists of a monitor, a camera, and a platform to place the reading materials or another near task to magnify the image and display the image on a TV screen or monitor. They have a wide of magnification usually from 2X to 60X. Additionally, the CCTV has no optical aberration and has control of illumination and contrast. It is very helpful for the patient with macular degeneration as illumination are important to ARMD’s patient as colour appears on their vision was faded and dimmed. Some CCTV model comes with speech output it can hear the text and useful for the patient with hearing impairment. It provide a larger field of view to let the patient use their peripheral vision or the remaining unhurt vision to read. Besides, it also can be linked to a computer or word processor which makes the patient able to read online materials. When using CCTV, the patient can have better posture and sit comfortably at their preferred working distance.In conclusion, CCTV will be the most suitable aid for the patient to do crosswords as crosswords need a larger field of view to read all the words on the page. The larger field of view provided by CCTV allowed the patient to read clearer and faster. Secondly, as macular degeneration progresses, it will need greater illumination to improve contrast and vision. The CCTV has the function of controlling the illumination and contrast, it would be very helpful when the macular degeneration gradually worsen. Doing crossword normally will take a longer time to finish, the patient can choose his preferred working distance and sit in a comfortable posture while using CCTV. It helps to reduce neck pain and fatigue. When using CCTV as an aid to help for the patient to improve their eyesight, the patient is also encouraged to use an Amsler grid to do training at home in order to use their clearest area of vision to see the center. In addition, to use a CCTV, the patient also can do a Steady Eye Strategy (SES) training to help them improve their reading speed and accuracy, it also may help the patient to use their remaining vision more effectively.

Post Author: admin

x

Hi!
I'm Erica!

Would you like to get a custom essay? How about receiving a customized one?

Check it out