By Purity M. Thuku
The introduction of visual electrophysiology testing could alter the digital landscape of the eye care industry in the country.
The diagnostic device, a MonPack machine, which is currently located at Nairobi Hospital, Anderson Centre is the only available visual electrophysiology test machine in East and Central Africa.
This was revealed by Dr. Muwale Onyango, a consultant ophthalmologist and vitreoretinal surgeon with Nairobi Eye Associates, saying the machine offers visual evoked potentials, electroretinography, electrooculography, standard visual field tests, contrast sensitivity and driver’s visual field tests.
Onyango said the imaging machine has capacity to fully document the retinal cell function, translating light stimuli into electrical impulses to the brain, subsequently creating a computer generated wave pattern interpreted to diagnose various eye conditions.
For instance in the driver binocular visual field examination, if the machine interprets a permanent defect above 33 percent, it means the patient does not see well enough to be a safe driver and thus is not supposed to handle a motor vehicle. This test is invaluable considering the upsurge in fatal road traffic accidents on Kenyan roads.
The machine has capacity to also aid in diagnosis of major conditions including diabetic retinopathy, macular edema, retinal detachment, retinal dystrophies.
The expert added that with retinal electrophysiological imaging, ophthalmologists will be able to get an interpretation of eye diseases they were not able to see before.
The eye specialist said that the machine which has been introduced in Kenya with a sense of unique urgency will transform and revolutionize eye care in the country and the continent.
With every health facility looking to offer high-quality care at reasonable costs, Muwale said electrophysiology machine comes with a patient-centricity concept and can give service to at least 15 patients on a daily basis.
Adoption of the services offered by the machine will accelerate the attainment of sustainable development goals and also strengthen Africa’s health systems.
Muwale said he integrates various instruments/electrodes to get accurate readings for all tests done. Such include: cupola, contact lenses, wire loops and fine hypoallergenic needles.
Medications used in connective tissue diseases like lupus and rheumatoid arthritis include hydroxychloroquine and steroids. These medications have been proven to affect retinal and optic nerve function. A drug used commonly to treat tuberculosis, ethambutol, is known to affect optic nerve function. In all these cases, should a patient present with mild visual loss, the machine objectively assesses and can quickly diagnose dysfunction long before it can become irreversible. This ultimately saves the vision of the patient.
The state of the art device will come in handy in and not limited to insurance and workman compensation claims. “ This is because we can now objectively confirm actual loss of vision after assault, road traffic and industrial accidents without relying on what the client is actually reading from the standard visual charts” intimated Muwale.
The imaging device can interpret eye problems related to accidents and reduce fraudulent claims. Thus, employers and insurance companies can take advantage of the machine before compensating a victim. This is through doing tests referred to as “Flash and Pattern Visual Evoked Potentials”.
In this case, the machine generates different impulses which are sent to the occipital lobe (part of brain that controls our vision) and subsequently the computer generates wave patterns that can confirm if the client has actually lost vision.
Further Muwale said retinal conditions characterised by extraordinarily poor vision either at night or in bright light and reduced fields of vision are being diagnosed. The machine performs the electroretinogram test and confirms which retina cell type has a defect. Various treatments are on trial for these diseases.
He added the machine will assist many patients in Africa who travel abroad in need of such tests. Health researchers and medical facilities, he said, will benefit from the technology.
“People in need of eye care services have for a long time travelled long distances and have had to pay a lot to access retinal electrophysiology services. The importance of the electrophysiology machine cannot be overemphasized,” said Muwale.
The surgeon also stated that annual eye testing by an ophthalmologist (eye doctor) for all persons over the age of forty is highly recommended, adding that at this point people begin to lose power to focus on small reading texts (presbyopia or middle age vision), spend long hours on computers leading to eye strain and unmasking of uncorrected refractive errors like short-sightedness.
Anyone with a first line relative suffering from eye conditions like glaucoma (optic nerve damage due to high eye pressure) needs annual review before the age of 40 years.
“It is also very important to have regular ophthalmic examinations if you are undergoing any treatment for a chronic condition such as hypertension, arthritis, diabetes, tuberculosis, HIV, high cholesterol, kidney disease because some of the medications or even the disease itself could potentially affect vision,” he said.
Muwale emphasized on the need to seek professional services from an ophthalmologist for credible examinations, saying optometrists and opticians cannot give you a clean bill of treatment.