In this edition of DocScopy, Dr. Nirainila Joseph from MedBound Times sits down with Dr. Abisha GN, an aspiring ophthalmologist. She completed her MBBS degree at Tirunelveli Medical College, Tamil Nadu, India. She is currently pursuing her Diploma in Ophthalmology (DO) at Dr. Agarwal's Eye Hospital in Tirunelveli, Tamil Nadu, India.
Dr. Abisha engages in a compelling conversation about diabetic retinopathy, a leading cause of vision loss. This interview sheds light on the causes, symptoms, and crucial management strategies for this prevalent eye condition. Get ready to delve into the world of diabetic retinopathy alongside Dr. Abisha's expertise to understand and address this critical ophthalmic concern.
Dr. Nirainila Joseph: Please introduce yourself to our readers
Dr. Abisha: I am Dr. Abisha. My native is Marthandam, Tamil Nadu. I completed my MBBS at Tirunelveli Government Medical College, Tamil Nadu. Now I am doing my Diploma in Ophthalmology (DO) in Dr. Agarwal’s Eye Hospital, Tirunelveli, Tamil Nadu.
Dr. Nirainila Joseph: To begin with, can you discuss the common lifestyle diseases that can negatively impact eye health?
Dr. Abisha: Many diseases affect the normal health of the eye. The most common one is diabetes. Prolonged duration of the disease course and uncontrolled diabetes may severely affect the blood vessels of the retina leading to diabetic retinopathy (DR). Following this uncontrolled hypertension can also lead to hypertensive retinopathy. High levels of cholesterol may cause xanthelasma (yellow growth near the eyelid) and even retinal vein occlusion. Thyroid eye disease is associated frequently with hyperthyroidism. Obesity and smoking have a high correlation with age-related macular degeneration.
Dr. Nirainila Joseph: Among lifestyle diseases that affect our vision, diabetic retinopathy stands out as a major concern. Can you walk us through the process of how diabetes affects the eyes and leads to diabetic retinopathy?
Dr. Abisha: Diabetes causes microangiopathy affecting retinal precapillary arterioles, capillaries and venules.
Thickening of capillary basement membrane
Capillary endothelial cell damages
Changes in RBCs
Increased stickiness of platelets
Microvascular occlusion
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Retinal ischaemia
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Capillary leakage neovascularisation, hemorrhage (DR)
Dr. Nirainila Joseph: Are there different stages of diabetic retinopathy, and how do they progress?
Dr. Abisha: There are two main stages of DR:
Non-proliferative DR (NPDR): It can be
Mild: Characterized by tiny swellings/bulges in the blood vessels of the retina (microaneurysm)
Moderate: Along with microaneurysm there will be hard exudates, cotton wool spots
Severe: 4-2-1 rule (at least anyone should be present); 4 quadrants of intra-retinal hemorrhage, 2 quadrants of venous beading, 1 quadrant of IRMA
Proliferative diabetic retinopathy (PDR):
Neovascularisation of disc or elsewhere (NVD/NVE), vitreous hemorrhage indicates PDR.
Dr. Nirainila Joseph: Many people with diabetes may be unaware that their vision is at risk until significant damage has occurred. Understanding the symptoms of diabetic retinopathy is crucial in ensuring timely medical intervention. Can you educate us on any specific symptoms a patient with diabetic retinopathy might experience, or can it progress silently?
Dr. Abisha: At initial stages, disease can present without any symptoms. But later on, patients may experience diminution of vision, poor night vision, floaters or dark spots, and diminution of color vision. Hence routine fundus evaluation for diabetic patients helps to detect the disease in early course and helps to prevent its progression.
Dr. Nirainila Joseph: Now that you mentioned the importance of a fundus evaluation for detecting diabetic retinopathy, let's explore further on how diabetic retinopathy is diagnosed, and what tests are typically performed?
Dr. Abisha: The diagnosis of DR begins with testing of visual acuity, colour vision testing. Clinically DR can be assessed by dilated fundus examination through a slit lamp or ophthalmoscopy. Optical coherence tomography (OCT) helps to detect the thickness of the retinal layer and finds any edema if present. Fundus fluorescein angiography (FFA) traces the leaking vessels in DR
Dr. Nirainila Joseph: Once detected, what are the current treatment options for diabetic retinopathy at different stages?
Dr. Abisha: Patient education regarding strict diabetic control and weight reduction is critical in treating DR. In mild cases patient should kept under observation and reviewed every 6 to 12 months. For moderate to severe NPDR patients look for the evolvement of macular edema. Intravitreal injection of anti-VEGF is needed for treating edema involving the macula and laser photocoagulation can be considered in cases with off-centre swelling when exudates threaten the fovea. Intravitreal triamcinolone injection increases visual acuity. Pars plana vitrectomy is indicated if there is any associated traction or recurrent hemorrhage. In the cases of high-risk PDR without macular edema, pan-retinal photocoagulation should be initiated.
Dr. Nirainila Joseph: We all know that prevention is better than cure. Can you discuss the regular screenings that diabetic patients need to undergo to detect diabetic retinopathy early and prevent vision loss? How often should a diabetic patient with no signs of retinopathy get a comprehensive eye exam?
Dr. Abisha: It is mandatory to screen diabetic patients every 6 months to 1 year inorder to diagnose diabetic retinopathy at an early stage and thereby complications related to DR such as macular edema, hemorrhages, detachment can be reduced thus preventing vision loss. The patients with no signs of DR should undergo dilated fundus examination atteast once every year.
Dr. Nirainila Joseph: That's quite informative! Now, what is the long-term prognosis for patients with diabetic retinopathy who receive timely treatment?
Dr. Abisha: The initial stages of diabetic retinopathy are reversible if proper glycemic control is achieved. Many patients with diabetic macular edema require long-term support of repeated injections of intravitreal anti-VEGF medications. Patients treated with pan-retinal photocoagulation may require additional supplementation of anti-VEGF medications if there is persistent macular edema and neovascularization. Once there is tractional macular detachment for a longer duration, the visual prognosis is usually guarded as the macular anatomy is markedly distorted.
Stay tuned for Part - 2!