By Dr. Domenic Turco

What is glaucoma?

Glaucoma is an umbrella term for the eye disease that causes progressive damage to the optic nerve over time.  There are different sub-categories of glaucoma such as open angle, closed angle, primary, and secondary, but they all demonstrate some form of optic nerve damage which can cause changes to both the appearance of the nerve as well as its function.  The term “primary” means that the patient has no known eye disease or systemic disease causing the damage, while the term “secondary” implies the opposite.  “Open” vs “closed” angle has to do with the anatomical structure of the angle of the eye, which is the location where fluid is drained from the front of the eye.  It is important to make these distinctions as different types of glaucoma are treated differently.  The most common type of glaucoma we encounter is primary open angle glaucoma (POAG).

What causes POAG?

The current understanding of POAG is that the fluid (aqueous humor) produced in the front part of the eye has increased resistance to drainage at the angle of the eye, which in turn causes a rise in the intraocular pressure.  There is a common misconception that one has to have an elevated intraocular pressure to have glaucoma.  Although we generally say that “normal” intraocular pressure is somewhere between 10-21 mm Hg, that is somewhat misleading as there are patients who demonstrate optic nerve damage and visual field changes despite having intraocular pressure in the so-called “normal” range.  What this means is that there are other factors at play which we do not yet fully understand, including hereditary/genetic and possibly nutritional/environmental influences.   Intraocular pressure is important because it is one of the few risk factors for glaucoma that we can modify with medication, lasers, and surgery.

How do you test for POAG?

When you see your ophthalmologist or optometrist for a glaucoma evaluation, you will likely undergo multiple tests to help make the determination of whether or not you have glaucoma.   These include measurements of visual acuity, intraocular pressure, and central corneal thickness.  Central corneal thickness is important as thinner corneas have been identified as a risk factor for glaucoma development.  Your doctor may also perform gonioscopy, which utilizes a special mirrored lens to look at the anatomy of the angle of the eye.  In addition to a slit lamp examination of your optic nerves, your doctor may also use an imaging modality such as optical coherence tomography (OCT) to look for areas of thinning of the nerve fiber layer surrounding the optic nerve.  Changes in the nerve appearance or increasing thinning of the nerve fiber layer can be signs of progressive damage to the nerve.  Finally, an assessment of your peripheral vision will be performed which is usually referred to as a visual field exam.  This test is very important as glaucoma generally tends to affect peripheral vision before if affects central vision.

How do you treat POAG?

Once the diagnosis of glaucoma is made, your doctor will decide on a treatment that will best suit your needs as well as your personal preferences.  As was mentioned earlier, intraocular pressure is one of the few risk factors that can be modified.  The vast majority of POAG is treated by instillation of topical eye drops to lower the intraocular pressure by decreasing fluid production or increasing fluid outflow.  There are multiple classes of medications designed to do this, and they include prostaglandin analogs, beta blockers, alpha agonists, and carbonic anhydrase inhibitors.  Each class has its own unique side effect profile, and your doctor should discuss the risks and benefits of each medication before starting treatment.  The most common initial topical therapy is the prostaglandin analog class secondary to ease of dosing, the fact that they are generally well-tolerated, and are effective in pressure lowering.  Some patients will require more than one topical medication for control of their pressure.

For patients whose pressure cannot be adequately controlled with topical medications or are intolerant of the side effects, there are the options of laser procedures and surgical procedures.  Two of the most common types of lasers include argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT).  Both lasers are generally well-tolerated and can be performed in the office setting.  The surgical options for glaucoma have been expanding in recent years, ranging from the traditional trabeculectomy to less invasive procedures commonly referred to as MIGS (minimally invasive glaucoma surgery).  It is beyond the scope of this article to go into all of the surgical options in detail, but they generally involve creating a pathway for fluid to drain from the eye and therefore lower the intraocular pressure.  Any surgical discussion should include the risks and benefits of each procedure option.

Premium/Lifestyle Lenses

By Dr. Jeffery Heimer

Advanced technology lens implants have been available to eye surgeons and their patients for many years.

These are a unique type of artificial lens implant placed following cataract removal surgery.

Generally, the most common lens implant used is called a monofocal implant.  These are excellent quality lenses and are made by several different manufacturers.  They provide very clear vision, though they focus images best at a specific distance.  Often, we try to obtain good distance for our patients, and they then use reading glasses for near vision.  We can, however, provide near or intermediate

vision with these lenses depending upon a persons desire.  Sometimes by slightly mixing lens powers we can offer a good range of vision with a limited need for glasses.  But generally glasses are necessary for certain tasks.  Monofocal lenses are covered by insurance.

Advanced technology implants address unique needs and desires of patients.  There are basically 2 types of these lenses.

These lenses are not covered by insurance and are paid out-of pocket.

The first is called toric.  This lens corrects astigmatism, which is a common and slightly irregular shape of the eye, which can be corrected with glasses.  For someone with astigmatism, this lens is an excellent way to correct vision and may minimize the need for constant spectacle correction.

The second type of lens is what are called presbyopia-correcting lenses, of which there are multiple different types including multifocal, trifocal, and extended depth of focus. The goal of their use is to provide a wider range of vision from distance to near, without glasses. While these lenses are not for everybody, they are wonderful for many people and represent truly advanced technology.

When cataract surgery is necessary, there are lens implant options which can be discussed in order to meet each persons unique vision concerns.

Facts About Cataracts

By Dr. Jay Fiore

A cataract is a clouding of the crystalline lens of the eye and a reversible cause of blindness.  The lens of the eye rests behind the pupil and is responsible for helping to focus light on the back of the eye (the retina).

Cataracts can affect anyone, of any age, but are more common in the aged population.  As cataracts develop, they block the passage of light through the eye and cause light to be scattered as it enters the eye.  This loss of quantity and focus of light leads to decreased quality of vision and visual acuity.

Early signs of cataracts include seeing “halos” and glare from lights at night as well as the inability to read road signs at the same distance one was once used to.  Eventually, cataracts lead to overall decrease in visual function leading to a decreased ability to read and perform activities of daily living.  Cataracts can cause frequent eyeglass prescription changes, double vision, and a fading of colors.  A typical cataract of aging will cast a yellowish hue to one’s vision, a process that happens so slowly that its effect typically isn’t noticed until the cataract is removed.

Cataracts most commonly are the result of the process of aging, but can also be derived from other causes.  Children can be born with congenital cataracts and require surgery before 6 weeks of age.  Secondary cataracts can develop from diabetes, radiation, corticosteroid use, and previous intraocular surgery, just to name a few.  Blunt force trauma to the eye can also trigger cataract formation.  Lastly, certain lifestyle choices can lead to early cataract formation, such as smoking, alcohol use, and prolonged sun exposure.

Fortunately, in the western world, going blind from cataracts is almost a thing of the past due to the many highly trained Ophthalmologists performing state of the art surgery.  Cataract surgery has progressed from a procedure known as Couching, where the cataract was pushed to the back of the eye and Coke-bottle glasses were worn afterwards, to today, where a cataract can be removed through a microscopic self-sealing incision with Phacoemulsification and a lens can be inserted into the eye to not only correct for one’s eyeglass prescription, but in certain circumstances, eliminate glasses entirely.

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