Avoidable Blindness

Dispelling the Myth... "Blindness runs in my family"
It is common folklore that disabilities, debilities and chronic diseases run in families, blindness no less. So many Jamaicans see it as their eventual fate to suffer illnesses similar to those of older family members. I am in no way discounting the principle of heredity, but I like to look at the positive side of things. The blindness that runs in families very often has roots in chronic lifestyle diseases. So the elderly in families who are poorly controlled diabetics and hypertensives are more likely to suffer blindness as a result of eye complications. In the 21st century medicine and information has changed the course of things. A new paradigm if you may. Being informed about the processes involved in eventual blindness can change what you may believe to be your destiny.

Vigilance
Early detection of diabetes and dyslipideamias (cholesterol problems), routine serology to check VDRL and other STD screens, supplementation in cases where dietary restrictions may compromise long term survival of the optic nerve (e.g. vegetarians and B 12 deficiency) are a few of the measures to prevent blindness in the vulnerable. It is imperative that primary health care providers are vigilant in monitoring control by regular, relevant testing. The HbA1c test in diabetics for example is a much better indicator of long -term control than a urine dip-stick or random blood glucose. Following a regime where eye exams are done upon diagnosis of diabetes, yearly after 5 years, and at least 6-monthly after 10 years of being diabetic ( or before and more often on the first sign of eye affectation) is key. There is treatment available to sustain close to 20/20 vision if general practitioners partner with ophthalmologists in early premorbid referral of patients. Individuals also need to take responsibility for their own eye health.

Glasses cannot cure eye diseases
Spectacles are designed to focus light and images on the retina where Rods and Cone cells transport signals via ganglion and other supporting nerve cells along fibres like electricity. These signals are taken to the brain via the optic nerves where they are translated into the images we see. So if the system that takes the signal is faulty, glasses cannot change the outcome. Glasses are not the cure or preventative measure for impending blindness. So, if your eye sight suddenly changes or there is noticeable vision disturbance especially combined with any disease for which you take medication, a fashion eyewear store or glasses dispensary should not be your first port of call, unless an ophthalmologist is in house. If it is, your optometrist should be able to detect sight threatening disorders and refer to the ophthalmologist.

Glaucoma.
This is a degenerative disorder of the eye nerve and retina with elevation of the eye pressure being one of the main risk factors. This disease still eludes us as doctors and researchers, as its presentation and course is so variable, as is its response to treatment. Early detection and strict control still avoids blindness in many. There is a hereditary component I admit, but this nerve-degenerating disease can pop up as a result of what we in medicine call comorbidities. So it may or may not be a family trait. If it is, then routine eye test should include intraocular pressure (IOP), funduscopy (+/- photography for good record keeping), gonioscopy (viewing the drainage angle at the front chamber of the eye), pachymetry (measuring the thickness of the cornea so the pressures can be better put into perspective), visual fields or perimetry (checking the width of vision and if there are gaps in it), and scan tests of the eye such as OCT and HRT to image the nerve fibre layer and optic disc of the retina. All these tools when combined are of great prognostic value, and help in planning the appropriate course of action and drug choice your ophthalmologist can employ.