Glaucoma Research at Doctor's Eye Institute

Many of our patients are unaware of the fact that Koby Karp Doctors Eye Institute has been involved in clinical research for new glaucoma medications since 1986.  These studies are Phase 111 studies, which means that the test medication has been through the drug-development process and is ready to be tested in the clinical setting.  Many of the medications that are tested are combinations of already approved glaucoma drops or these same drops in a different delivery solution.  For example DEI was involved very early in the clinical trials for TIMOPTIC XE, which is the same Timpotic medication in a longer lasting solution.  This has made it very easy for many of our patients to control their glaucoma with just drop a day !

Drs. David Karp and Melvyn Koby feel that by participating in these clinical trials our patients are given the opportunity of receiving quality eye care while using the latest in glaucoma therapy developments.  The patients are seen on the same schedule ( or often a more frequent schedule ), as they would normally adhere to for their glaucoma follow up care.  These visits and the glaucoma medication are provided at no charge by the pharmaceutical company.  Many patients find this an incentive to participate in the clinical studies.

DEI has a number of patients who have participated in several studies over the past years.  Dr. Koby and Dr. Karp are very grateful to these patients for their commitment and interest in the development of medications that not only help control their  disease but may also be the drug that will be used by future generations.  Since glaucoma is often an inherited disease, these patients may be helping to provide the medications that will be used by their own children and grandchildren.

If you would like more information regarding clinical studies or would like to see if you are a candidate for these, please call the office at (502) 897-1604.

About Glaucoma

The term "glaucoma" refers to a group of diseases, not a single disease.  It is not easy to define the term precisely as it is not as simple as "high pressure" in the eye.  The underlying problem is gradual death ( or the potential for this degeneration) of nerve cells in the optic nerve.  This can lead to eventual loss of peripheral vision and finally, total blindness.  Most forms of glaucoma are associated with high eye pressure.  This pressure is measured as part of a complete eye examination.  High eye pressure is a risk factor for glaucoma. It is currently the only risk factor for glaucoma which can be altered by treatment.  Therefore, people tend to think of glaucoma and high eye pressure as the same thing, but it is not so simple.

The interior of the eye maintains pressure, like an inflated basketball, to prevent the walls from collapsing inward.  "Aqueous" fluid is produced by cells behind the iris ( colored part inside the eye ) and flows through the pupil ( hole in the iris ) into the anterior chamber.  At the angle where the cornea meets the iris, there is a drainage meshwork which allows fluid into the bloodstream.  The resistance to this  flow of fluid maintains a pressure inside the eye.  As millimeters of mercury, the normal eye pressure is typically between about 8 and twenty one.  If the pressure is found to be higher than this, or if there are signs of optic nerve damage or other risk factors for glaucoma, we will often recommend further testing of the optic nerve function.  This may include visual field testing to see the extent of any peripheral loss.

The GDx nerve fiber analyzer is a more recent method of detecting and following glaucoma damage, possibly demonstrating a change in nerve cells before any peripheral vision is lost, therefore detecting glaucoma earlier.  This technology represents a recent advance in management of glaucoma, as early detection is important.  Optic nerve cells  which die cannot be restored, so once we know that deterioration is happening, we can recommend treatment.  GDx takes a special photograph of the area around the optic nerve, using light characteristics to measure the layer of cells which are affected in glaucoma.  This may begin to show changes before any vision is lost and we can recommend treatment at this earlier time.

The visual field test involves active participation.  As you look into a large white bowl shaped 'perimeter',  small dim lights will blink in the peripheral vision.  As you press a button to indicate that you see the light, the computer keeps track and reconstructs a visual field.  This test takes 15 to 30 minutes and is often done yearly to follow glaucoma.  The goal of treatment of glaucoma is to halt the progressive loss of vision.  So if the field test is followed from year to year, this is helpful information.

Glaucoma may be categorized into two main categories.  This is because the types of symptoms and findings and treatments are quite different.  Open angle glaucoma (OAG) is the more common category, the 'garden variety' of glaucoma.  This means that the iris cornea angle is open, and flow of fluid is not obstructed before reaching the "angle", where fluid leaves the chamber.  Within the angle meshwork, the fluid meets high resistance.  This is normally the primary, inherited type of OAG or POAG.  Occasionally, some material may block the meshwork system, such as pigment material or inflammation cells or blood cells.  These may be categorized as Secondary OAG  (SOAG).  The treatments are similar, involving long-term control of eye pressure.

Narrow Angle Glaucoma, Acute Angle Closure and Angle Closure Glaucoma are the other broad group of glaucomas.  With these forms of glaucoma, the angle where fluid is to leave the eye is blocked in some way by the iris edge.  Some people have naturally small eyes, often farsighted, and a crowded anterior chamber.  Fluid flow can actually be blocked due to iris covering the angle, and a sudden extreme rise in pressure may occur.  This is more sudden than the normal "open angle" forms of glaucoma.  The pressure may rise so high as to cause pain and redness and blurry vision.  Sometimes on examination, there is evidence of wide pressure fluctuations without symptoms, and possible damage to the optic nerve (ACG).  The normal treatment for this form of glaucoma is laser treatment to create a small hole in the edge of the iris.  This is performed in the office, and it is possible that this can actually "cure" the problem.  Some people may still need eye drops on a regular basis.

Treatment of  most patients with glaucoma usually begins with eye drops.  There are several commonly used drops, many are once or twice daily doses.  Some patients may be candidates for laser treatment to lower eye pressure.  Selective Laser Trabeculoplasty (SLT ) is a relatively recent advance in treatment of open-angle glaucoma.  Drops can be altered based on effectiveness and side-effects, laser treatment can be used to lower pressure, and surgical treatment is another option for lowering of pressure.