Glaucoma Treatment FAQs
What is Glaucoma?
Glaucoma is one of the most prevalent causes of irreversible blindness. It is defined as an optic neuropathy usually associated with high intraocular pressure. What this means is that the optic nerve, which connects the eyeball to the brain is damaged and the number one modifiable risk factor is the intraocular pressure, or pressure within the eye. Dr Grange is fond of saying that just like high blood pressure can lead to strokes and heart attacks, high eye pressure can lead to glaucoma. Glaucoma can be a "silent killer" in that many people will lose significant amounts of peripheral vision from glaucoma and not be aware until glaucoma is quite advanced. People can be considered legally blind and still retain 20/20 distance vision because they have tunnel vision - in other words, they have lost all peripheral vision due to advanced glaucoma. Occasionally glaucoma is hereditary, and that is why you will be asked if you have a family history of glaucoma. There is a whole host of ways that you will be screened for glaucoma by your eye doctor, and nowadays there are many efficacious ways of treating this condition. Everyone from newborns to the elderly can develop glaucoma. Glaucoma is prevalent in people of East Asian decent, African Americans, Native Americans, and Mexican Americans.
Are there different Types of Glaucoma?
There are many different types of glaucoma. Usually a distinction is made between NARROW-ANGLE and OPEN-ANGLE glaucoma. This has to do with the shape of your eye, and the angle in question is the angle between the cornea (the clear dome in the front of your eye) and the iris (the colored part of the eye). Fluid typically circulates from behind the iris to in front of the iris and drains through the angle of the eye.
Individuals with NARROW-ANGLES should avoid certain medications with black-box warnings (anti-histamines, etc) as they are prone to narrow-angle attacks in which the eye can become intensely painful and blurry and you can develop nausea and vomiting. As cataracts worsen in patients, many times the angle of the eye becomes more and more narrow, which results in higher and higher intraocular pressures before cataract surgery. If your eye doctor informs you that you have NARROW ANGLES the primary treatment would be one of two things. If you have cataracts, then your best option is usually cataract removal, as this almost invariably opens up the angle of the eye and reduces intraocular pressure. If you are young and you don't have cataracts the best approach is probably the one called laser peripheral iridotomy, or LPI. An LPI is a microscopic hole in the iris created by Dr Grange with a specialized laser. This LPI opens up accessory drainage pathways in the eye, such that the risk of high eye pressure due to narrow angles, or narrow-angle attacks is diminished. LPI creation is relatively painless and is covered by insurance. Occasionally LPIs seal closed on their own as the body heals, in which case Dr Grange would discuss whether or not to create a new LPI.
OPEN ANGLE glaucoma is much more prevalent and more associated with aging eyes, especially in African Americans, those with Northern European Decent and Latinos. There are many treatments ranging from minimally invasive to extremely invasive, and they are all covered by medical insurance. Common first approaches which are considered minimally invasive would include drops to lower your intraocular pressure, or a laser treatment to stimulate the drainage cells within the eye called Selective Laser Trabeculoplasty or SLT. SLT has been shown to be a one-to-one correlate with the strongest glaucoma drops and allows the patient more independence from drop therapies. The effects of SLT typically last for years on average, and SLT treatments can be repeated as often as needed. More advanced interventions would include a medication implanted into the eye in pellet form which slowly dispenses medication over months (e.g. Durysta), or intraocular procedures like ab-interno canaloplasty using the OMNI device (see below). If you have cataracts, Dr Grange will discuss cataract surgery adjuncts which are covered by insurance which will help you manage your glaucoma.
What is ab-interno canaloplasty (OMNI Device)?
Dr Grange favors the OMNI device from Sight Sciences for many of his glaucoma treatments. It is a minimally-invasive procedure which is covered by medical insurance to help lower the intraocular pressure. It is approved both in conjunction with cataract surgery (done simultaneously during cataract removal), or as a stand alone procedure. Dr Grange has a distinguished track record of success using this procedure to help control intraocular pressure, and he will be more than happy to discuss it at length. There are few risks (mostly the ones germane to any intraocular procedure - i.e. possible infection, blurry vision during recovery, need for repeat operation), and most patients are thrilled with the results.
In terms of how it works, Dr Grange enjoys telling his patients that glaucoma is fundamentally a plumbing problem and that high pressure is either the result of too much fluid being produced or too little fluid draining out of the eye. He is a proud micro-plumber and uses the OMNI device to open the drain in the eye and lower the eye pressure. In technical terms, this device threads a micro-catheter through Schlemm's canal and the trabecular meshwork in order to visco-dilate these structures and thus lower the intraocular pressure.