Macular degeneration

Introduction

Macular degeneration, or as its more commonly known as Age-related macular degeneration(AMD). It is one of the cause of irreversible blindness among people who are in their golden years (Waugh et al, 2018). There are 2 types of AMD which are Dry AMD and Wet AMD. Dry AMD being characterized by the atrophy of certain areas of the retina, in layman terms, certain parts of the nerves in your eyes are dying or have stopped working (Waugh et al, 2018). Wet AMD would be characterized by abnormal new blood vessels growing in the retina, causing swelling mainly in the central part of the retina, causing vision loss (Waugh et al, 2018)  

left : normal vision , right : permanent dark spot that blocks the vision for AMD patient

Signs and symptoms

Most patients don’t get any obvious symptoms in the early stages of the diseases. An optometric examination will take place to detect AMDs. In dry AMD patients, they typically report that the central vision is slowly deteriorating. However, the deterioration happens much more rapidly in wet AMD, sometimes in the matter of days (Horton & Guly, 2017). Hence, when checked with the amsler grid, which is a grid with many small squares, the patient will have to focus on a black dot in the middle of the grid and describe what they see. Usually the patient would report that the lines on the amsler grid is not straight or the squares look distorted or blur.  

Treatment

For dry AMD, there’s very limited amount of treatment options. Usually, suggestion for treatment is that to go on a specific vitamin regiment and live a generally healthier lifestyle. Besides, patient will also be asked to quit smoking if they do smoke (Horton & Guly, 2017). For wet AMD, the one and only treatment available so far is the injection of anti-vascular endothelial growth factors (Anti-VEGF).

The administration of these drugs can stop the production of abnormal blood vessels and improve the visual acuity of the patient (Horton & Guly, 2017). The anti-VEGF are administered through an intraocular injection which means that a syringe will be inserted into the eyeball and the drug is administered straight into the eye. There has been a recent study on improving the vision of AMD patients by treatment with a corneal elastic modulus-altering procedure. This procedure basically alters the geography of the corneal to let the light hit the good parts of the retina instead of the bad parts, therefore, improving vision. However. this procedure is still being tested (Serdarevic et al, 2017).  

Prevention

AMD does have a genetic disposition. However, recent studies have found that prolonged exposure to high energy blue light can also damage the retina. Therefore, causing AMD to occur earlier in life (Zhao et al, 2018). To cut down on one preventable cause of AMD, we implore our readers who are digital natives to start using blue filter lenses. This is to protect your eyes, provided that your job does not entail very accurate colour discrimination. This is due to blue filter lenses tend to have a faint yellow tint which may affect colour perception.

References

Horton, S., & Guly, C. (2017). Prevention and treatment of age‐related macular degeneration. Prescriber, 28(1), 37-41. Serdarevic, O., Tasindi, E., Dekaris, I., & Berry, M. (2017). Vision improvement in dry and wet Age‐Related Macular Degeneration (AMD) patients after treatment with new corneal CPV procedure for light redirections onto the retina. Acta Ophthalmologica, 95. Waugh, N., Loveman, E., Colquitt, J., Royle, P., Yeong, J. L., Hoad, G., & Lois, N. (2018). Introduction to age-related macular degeneration. In Treatments for dry age-related macular degeneration and Stargardt disease: a systematic review. NIHR Journals Library. Zhao, Z. C., Zhou, Y., Tan, G., & Li, J. (2018). Research progress about the effect and prevention of blue light on eyes. International journal of ophthalmology, 11(12), 1999.

HOW CAN AN OPTOMETRIST HELP YOU?

What does an optometrist do?

A question that has been popping up a lot more recently due to the more informed public this age. Well fret not, in this post I’m going to talk about how can an optometrist help you.

Who is an optometrist?

An optometrist is a health care professional that are trained to handle ocular diseases and binocular anomalies on top of what the optician does which is refraction, lens edging and dispensing. We are also trained in specialty lens fittings such as rigid gas permeable (RGP) lenses, Rose-K and Ortho-K lenses.

What do they do?

In short, we are the primary care practitioners who are responsible to detect and solve problems with the eyes with ophthalmic lenses and contact lenses. We will then referr to ophthalmologists on an indication of a disease that may need medical intervention.

What should you look for from an optometrist?

We are trained in many different refraction techniques to deal with different types of eyes. This is to ensure that we get an accurate refraction results every time. In our kit, we have a Retinoscope and an Opthalmoscope.

The retinoscope is a tool that we use to determine the person’s power. Although these days we prefer to use an autorefractor which is the scanner that scans your power before we bring the you into the refraction room due to its speed, but when there is an indication to use it, such as when we notice that the astigmatism is too high, with the scope we can actually determine if the person would have keratoconus. In some more serious cases of cataracts, we can detect using the retinoscope as well.

The opthalmoscope is basically a magnifying glass to look in to the eye to check the retina. Usually the optometrist would turn off the lights and tell you to look at a specific direction. After that we would get close with the opthalmoscope to check the clarity of the ocular media. At this point we are able to determine if a person has cataract or not.

Then, we focus on the retina. The things that we would check for would be the ratio between the blood vessels, hemorrhages, leakages and also the optic nerve head. With that, we can determine if the person’s blood pressure and blood glucose level are at normal level, and the possibility of getting glaucoma. If you’re having pink eye, we would use a slit lamp, which is a microscope, to check the surface of your eye and the inner eye, to determine the cause of the red eye. Note that cause of a red eye could be bacterial infections, viral infections, allergies and foreign objects.

What about the kids?

Kids under the age of 6 are also more than welcome to be screened for lazy eye. Lazy eye could result in permanent loss of visual if it is left unattended. Therefore, it is prudent for us to check for the signs and symptoms before it is too late. We can also manage kids with squint eyes (mata sepet), with specialty prism lenses so that they don’t later develop lazy eyes as well. In some cases, prescribe in office training to help training kids’ eye muscles so that they’re aligned and look normal again. With all the technicalities aside, optometrists can also deduce the condition of your eyes through questions. In our book, there is a word of advice: 70% of the time, the patient would tell you their diagnosis. Its just that the patients are not aware of their conditions, so we are also there to inform and educate.

When should you see one?

Whenever you feel like your vision is not as good as it should be, eyestrains, headaches after long hours of work, persistent itching in the eyes, mucus discharge in the eyes, the list goes on. In a nutshell, optometrists possess the skills and knowledge to help you with more than just your vision but also your health. Book an eye check with optometrist today!