On March 19, 2022 Seniors Today hosted another one of its weekly Health Live Webinars. This week we had with us Dr Nikhil Sardar. World Glaucoma Day was observed last week on March 12th. To mark the occasion, we invited Dr Sardar to speak on glaucoma.
Dr Nikhil Sardar is a veteran ophthalmologist attached to the Nanavati Max Hospital. After completing his MBBS from Pune, he did postgraduate training in ophthalmology from AFMC, Pune. He has spearheaded various ophthalmology departments and done countless complicated ophthalmic surgeries.
Glaucoma is a silent blinder or a thief of sight because you don’t even come to know that you have glaucoma.
There is damage to the optic nerve ganglion cells and fibres. There is death and destruction of this layer, leading to thinning of this layer.
The optic nerve is attached to the retina behind. There is endangerment of the cup disc ratio in glaucoma.
This happens because of:
Increase in the intro ocular pressure. This causes no redness, irritation or pain or blurred vision till it’s too late.
Central vision is not affected till the very end.
Causes of glaucoma:
- age related
- Rise in the intra-ocular pressure. The normal pressure inside our eye is between 8-20 mm of Hg.
- Anatomical reasons- individuals with high (-) number (myopic individuals) they are prone to open angle glaucoma. Individuals with high (+) number are prone to angle closure glaucoma.
- Trauma, swelling in the eye.
We can call an individual a glaucoma suspect if he has any one of these 4 things:
- Physiological cupping: an individual whose optic nerve looks like that of someone with glaucoma but he does not have raised eye pressure, or any other damage. And his vision is also normal. This is usually seen in individuals with large/ big eyes, patients with high myopia. It’s a pseudo glaucoma like picture.
- Glaucoma proper/ open angle glaucoma: these individuals have raised interest ocular pressure. His retina and optic disc will have a large cup:disc ratio. In perimetry or visual field assessment of the individual we will be able to find visual field defects.
Such an individual will have high pressure, loss of peripheral vision and the retinal image also shows damage of the optic nerve.
- Normotensive glaucoma: this is the most dangerous type of glaucoma. This patient will develop severe advance glaucoma and severe field defects but with normal intra ocular pressure.
This is usually seen in thin, frail ladies with low blood pressure. It is also seen in individuals with nutritional deficiencies and malabsorption syndromes.
The investigations that are carried out to diagnose glaucoma include:
- Intra ocular pressure is tested
- Visual field test: it is a subjective test to find out where the optic nerve is damaged from. The visual field constricts in glaucoma which ultimately leads to tubular or tunnel vision. It is the most important investigation for diagnosis and progression
- Central corneal thickness
- Optical core and stompgraphy
- Checking for nutritional deficiencies
- Gonioscopy: done to measure the angle of the eye. This is done for angle closure type of glaucomas.
Treatment modalities include:
- Medical
- Surgical: this is the last resort since surgery in glaucoma is very unpredictable. It is done only when all medical treatment fails.
Medical treatment includes
Anti-glaucoma drops
- Timolol or similar drugs
- Prostaglandin analogues
- Brimonidine
- Dorzolamide
We start with one of the above, monitor the pressure and then add the second in case there is no drop in pressure and then the 3rd and 4th line drugs keeping the patient pressure in mind.
The objective is to maintain a target pressure that does not lead to any further progression of the glaucoma
