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What is glaucoma?
Glaucoma is a disease that damages the eye’s optic nerve. The optic nerve sends signals from your eye to your brain, where these signals are interpreted as the images you see.
If the drainage angle is blocked, excess fluid cannot flow out of the eye, causing the fluid pressure to increase.
In the healthy eye, a clear liquid called aqueous circulates inside the front portion of your eye. To maintain a constant eye pressure, your eye continually produces a small amount of aqueous fluid while an equal amount of this fluid flows out of your eye.
The fluid flows out through a very tiny drain called the trabecular meshwork via a channel called the drainage angle.
If you have glaucoma, the aqueous does not flow freely through the trabecular meshwork. Fluid pressure in the eye builds up and over time causes damage to the optic nerve.
Glaucoma can cause blindness if it is left untreated. When glaucoma develops, usually you don’t have any early symptoms and the disease progresses slowly. As a result glaucoma can steal your sight gradually. Thankfully, early diagnosis and treatment can help protect your vision.
Types of glaucoma:
Open-angle glaucoma
The most common form of glaucoma is called primary open-angle glaucoma. It occurs when the drainage angle /trabecular meshwork of the eye becomes less effective at removing fluid from the eye. As a result the pressure in the eye, called intraocular pressure (IOP), rises. Raised eye pressure leads to damage of the optic nerve.
Usually, open-angle glaucoma has no symptoms or visual symptoms in its early stages. As the optic nerve becomes more damaged, defects (blank areas) appear in your field of vision. You usually won’t notice these defects until the optic nerve is significantly damaged and the defects enlarge to encroach on your central vision. If all of the optic nerve is damaged blindness results.
Normal-tension glaucoma
Eye pressure is expressed in millimetres of mercury (mm Hg). 50% of patients with glaucoma do not have high eye pressure when first examined. This is because glaucoma can occur without raised intraocular pressure called normal tension glaucoma.
Although normal eye pressure is considered a measurement less than 21 mm Hg. Patients with normal tension glaucoma have eye pressures consistently below 21 mm Hg, but optic nerve damage and visual field loss still occur. People with normal-tension glaucoma have the same types of treatment used for open-angle glaucoma.
Conversely, ocular hypertension is a condition where someone has higher eye pressure than normal, but does not have other signs of glaucoma, such as optic nerve damage or visual field defects that show up in their peripheral vision (visual fields) when tested. Someone with ocular hypertension is considered a “glaucoma suspect” because he or she may be at risk for developing glaucoma later. Just like people with glaucoma, people with ocular hypertension need to be closely monitored by an ophthalmologist to ensure they receive appropriate treatment.
Closed-angle glaucoma
A less common form of glaucoma is closed-angle, or narrow-angle, glaucoma. Closed-angle glaucoma occurs when the drainage angle of the eye becomes blocked. Unlike open-angle glaucoma, eye pressure usually goes up very fast. The pressure rises because the iris — the coloured part of the eye — partially or completely blocks off the drainage angle. If the drainage angle becomes completely blocked, eye pressure rises quickly resulting in a closed-angle glaucoma attack. Symptoms of an attack include:
• Severe eye or brow pain;
• Redness of the eye;
• Blurred vision;
• Seeing coloured rainbows or halos;
An attack of closed-angle glaucoma attack is a medical emergency and must be treated immediately. Unfortunately, people at risk for developing closed-angle glaucoma often have few or no symptoms before the attack. Treatment of this type of glaucoma involves eye drops, oral medications to reduce intraocular pressure and sometimes laser surgery to the iris.
I had my squint eye operation done by Dr Kathryn Mc Creery. I cannot thank her and her staff enough for their wonderful help in getting me my operation done successfully and professionally. Her staff were unbelievably friendly and made the experience so much better. Plus Dr. McCreery who rectified the turn in my eye gave me my confidence back. The experience was a very positive one, from start to finish they helped me. Thank you so much.
Roslyn Gallagher
Ms. McCreery carried out laser eye surgery on me about two months ago after 15 years of being totally dependent on glasses, it's hard to imagine I ever wore glasses now! Would 1000% recommend anyone who is considering laser to see Dr McCreery - every step of the process was so easy and I felt very well looked after by her and the entire team at Blackrock Eye Care. Couldn't be happier with my treatment and the results!
Deirdre Meehan
After many years weighing up the merits of getting laser eye surgery; I decided to have a consultation with Ms. Kathryn McCreery to establish suitability. The initial assessment was straightforward and the options and considerations were clearly explained to me. The surgery itself (PRK) was incredibly quick and painless. The results were even better than I could have hoped for and I now enjoy a quality of vision that is superior to that which my glasses used to provide. Although there are plenty of practitioners in this field; I went with Blackrock Eye Care as it is medical professional led rather than marketing led. The depth of experience, quality of aftercare and service level are what mattered to me. I highly recommend.
Ciaran Gorman
I recently had strabismus surgery with Kathryn McCreery and I'm absolutely delighted with the results. The surgery was done in the one day with no pain afterwards, only mild discomfort. My depth perception returned very quickly and the difference is unbelievable both cosmetically and comfort wise. Everyone was very friendly and professional from initial consultation to the surgery and after care. They took their time explaining everything to me and really looked after me. I had my consultation in March and surgery a few weeks later. I still can't believe the results and I'm delighted. Thanks to all in the Blackrock Eye Care. I can't recommend them enough
Mark Grenham
When my husband had his cataract surgery last year, we always felt great confidence in Ms. McCreery and thanks to her and the professional team, Pat made a great recovery and has his quality of life back.
Bernadette Quinn
Lasik gave me such great results, I don’t know why I waited. I would recommend Blackrock Eye Care & Ms McCreery to anyone who is eligible for the surgery
Patrick Molloy
For years my son suffered from his squint. When we finally sought treatment, we went to Blackrock Eye Care and the team were fantastic to Mark. He had his treatment and has never looked back, it was life-changing!
Pamela Byrne
Our son Jack (15 months) had a turn in his eye and from the very first appointment with Ms McCreery, we had full confidence in her and of the quality of the treatment Jack would receive. We have had this confidence reinforced at every appointment. Ms McCreery is an absolute expert in working with children and diagnosed immediately the issue and identified a course of action for Jack which involved a surgical procedure. As parents, this was a daunting experience however Ms MCreery’s whole surgical and nursing team were incredible in their attention and thoughtfulness for us and this made all the difference to our experience. The surgery has been a huge success and we are delighted with the outcome. I cannot express enough my gratitude to Ms McCreery and her team and we would highly recommend her to any parent.
Sean Flynn
I recently had a Lasek procedure with Ms. Kathryn McCreery in December 2016 and the whole experience was very positive . I had a speedy appointment booked at short notice, I went in had my procedure which took no longer than 5 minutes per eye and it all felt as easy as if going for a dental check up. Instantly after the procedure I could see much clearer. A week passed and I had clearer vision than through my contact lenses, i just thought how simple the procedure was and how much relief and benefit it gave. I now have better than 20/20 vision and Keep thinking why didn't I do this before. I also however don't believe it would have been as successful and such a seamless process had I not been looked after by Ms. Kathryn McCreery and her staff who are heavily experienced in this field and would highly recommend her and Blackrock Clinic if you want a more improved quality of life.
Sam Hussain
I would highly recommend Ms. Kathryn McCreery & her team. They explained everything that I needed to know to make me feel comfortable prior & post laser surgery. My care on the day was fantastic as was the follow up care I have received the days and months after. My advice would be stop thinking about it & do it, you won't regret it, the best decision I have ever made, life changing
Davinia O'Keeffe