Glaucoma is a silent disease that always results in blindness if not properly treated. There are several types of glaucoma, but all are a result of increased pressure within the eye, and a corresponding decrease in blood flow to the optic nerve. Like most diseases, treatment of glaucoma has evolved over the years, and knowing what must be done and considered when therapy is administrated can make the difference between life long vision and ultimate blindness.

There are 10 considerations that should always be kept in mind when treating and suffering from glaucoma.

1) Prostaglandins are one of the newest medications that are employed to treat glaucoma. They are extremely efficacious, and have a low rate of side affects. Therapeutically, Travatan and Lumigan are a little more affective the Xalatan in lowering intra-ocular pressure, but Xalatan has fewer side affects. Travatan lowered pressure and average of 8.7 mm Hg, and Lumigan 5.5 mm Hg while Xalatan was at 4.8 mm Hg. There is no ethnic difference with prostaglandins efficacy. The major issue when prescribing these medications are their tremendous expense.

2) Pachometry, or measuring corneal thickness; is a must when evaluating and treating glaucoma patients. The importance of Pachometry was clearly shown during the Ocular Hypertension Treatment Study, (OHTS). Corneal thickness will affect both the actual measurement of the Intra Ocular Pressure(IOP) using Goldman Tonometry and the target IOP. Corneal rigidity greater the 520 um will result in higher than actual IOP readings and thinner corneas will display lower than actual IOP. The problem is how much higher or lower as a result of this rigidity issue. Therefore a patient being treated for glaucoma with thicker corneas is at greater risk of vision loss then one with thinner corneas. The greater the thickness, the greater the danger, and the converse occurs for thinner corneas.

3) Strong patient-doctor relationships are essential. Glaucoma is a life long disease that will be asymptomatic until the later stages of the disorder. Therefore the patient must trust his/her doctor despite not feeling any different while under going therapy. The patient must be well educated by the eye doctor and shown the results of each test be they Visual Fields, IOP readings, and OCTs. Trust and follow up is the key.

4) Gonioscopy is a must. Anterior angle measurement will help diagnose some forms of glaucoma and follow any changes in this important structure as therapy continues. If laser treatments are done, gonioscopy should be performed more frequently.

5) The patient must understand that their treatment is for life. The most important component to the success in glaucoma therapy is patient compliance. If all is done perfectly well, but the patient fails to take the medication as prescribed, then failure is inevitable. With the new medications that require single daily administration, compliance has improved, but contact reminders are required at each follow up visit.

6) Ethnicity is an important factor that must be considered. Based on the Baltimore Eye Study, African Americans are twice as likely as Caucasians to go blind in both eyes as a result of glaucoma. While there are many other factors that must be included in the diagnosis and therapeutic process, ethnicity and race must never be over looked or minimized.

7) The optic nerve heads must be studies stereoscopically at the onset of the diagnostic process, and continued as the condition evolves. An even subtle change in one quadrant of the nerve head is significant in the progression of the disease.

Is Diabetes a risk factor? While Diabetes is pretty much a risk factor for most diseases, and complicates; there is no direct evidence to support the relationship between Diabetes and glaucoma. In addition, while the OHTS data suggested that Diabetes was a protective factor against glaucoma, recent studies have failed to prove that factor as well. Basically, having Diabetes is neither good nor bad with regard to glaucoma.

9) Compliance depends on how many drops, and how often they must be taken. A recent study demonstrated that 49% of patients took their eye drops regularly when required to do so once per day, but that number dropped to 39% when patients were required to use more then one drop or administer them more then twice per day. The compliance dropped like a rock in a pond the more frequently the drops had to be used. Therefore, to improve compliance the doctor must use the least number of drops, the least number of times per day. Cost was a major factor especially in the fixed income group of patients as well.

10) Finally, glaucoma therapy is always evolving and improving. It is incumbent upon the doctor to keep abreast of all new therapies, and also keep an open mind as to different types of therapies. The Age Related Eye Disease Study, AREDS, suggested that nutraceuticals were effective in combination therapy for glaucoma. This concept is controversial, but must not be ignored. Combination drugs and new innovative treatments should be considered in all cases, and the need may arise.

Glaucoma is a difficult disease to treat and manage over the many years that a patient must deal with it. Therefore all options and developments must be kept on the table.

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The pursuit of visual correction has taken many paths over the years, some better then others. On occasion, a protocol that is intended for one use can be applied to another with results that exceed its original intentions. Such is the case with Intacs, which are corneal implants to correct visual anomalies.

Intacs are corneal implants that are surgically inserted into the matrix of the cornea to flatten the curvature of the structure. They were initially developed as a refractive technique to reduce or eliminate nearsightedness between 1 and 3 diopters. When the procedure was first performed after FDA approval in 1999, 97% of the post surgical patients were able to see 20/40 or better with 74% seeing 20/20. However, complaints of glare, poor night vision, halos, and under/overcorrection; resulted in 39% of these patients having the Intacs removed. In almost all these cases, the cornea returned to its original shape and refractive power with in 1 year.

Intacs work by flattening the corneal surface, and thus refocusing light on to the retina. The parameters of the procedure were quite limited, to 1-3 diopters of myopia, and the visual side affects were unpleasant resulting in the demise of the procedure. In addition, with the introduction of LASIK, Intacs as a refractive procedure died an early death. However, a creative surgeon realized that patients with Keratoconus would benefit from this surgery. Keratoconus is a progressive, genetic corneal condition whereby the cornea becomes steeper, thinner and distorted over time. This results in reduced vision and often visual distortion that are not fully correctable by conventional eyeglasses. Hard contact lenses are frequently worn, but discomfort can limit their wearability.

In 2004 the FDA granted Intacs a Humanitarian Device Exemption to allow its use on Keratoconic patients to flatten out the distorted cornea, and permit clearer, more stable vision many times with out the use of hard contact lenses. In 2006 the FDA formally recognized Intacs as a therapeutic device for surgical correction of Keratoconus. They are used for long term correction, but can be removed at any time should the need arise. The Intacs come in several sizes depending on need and desired results. In Keratoconus; by altering the shape of the cornea a smooth refractive surface will permit a sharper focal point of light on to the retina and thus a clearer image.

Some patients have developed eye irritation post surgically, and in a few cases abnormal blood vessel ingrowth (neovascularization) has also occurred. It also should be noted that in 5% of these cases there was no visual improvement post-surgically. Obviously the true success of this procedure will depend on the severity of the Keratoconus and degree of corneal distortion. Dr. Thierry Hufnagel of Long Island has performed many Intacs implants on Keratoconus patients, and has remarkable success. He chooses his patients very carefully in order to select those that will be best served by this surgery.

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Contact lens solutions have evolved drastically over the past 50 years. They started as a multi-procedure activity that included cleaning, disinfecting, and soaking. These procedures could take hours to complete, and compliance was poor while the cost was high. As technology improved, so did the solutions. First, multiple steps were combined. The cleaner was incorporated into the rinsing and soaking step, but enzyming still was required. Recently, the solutions were able to incorporate an enzymatic component so all the wearer had to do was use one bottle of liquid.

This combination of elements dramatically improved wearer compliance since individuals needed to perform only one step. They did however; still have to rub the contact lens in the solution prior to letting it soak for several hours. Complacency resulted in many non compliant wearers that did not rub the lenses, and consequently did not fully clean their lenses. This resulted in an increased number of infections, ulcers and cornea complications. Additionally, solution manufacturers were concerned with the tearing of contact lenses which was caused by the manual handling of the contacts during the cleaning process.

The next step was the NO RUB solutions. They essentially were the one step type, but required only to rinse, and drop the lens in the solutions. It eliminated the need to rub and thereby reduced tearing, and increased compliance since there was nothing the wearer had to do that required effort. The NO RUB solutions have been used for several years, but recent studies conducted by doctors working on behalf of the FDA have demonstrated that this process may not fully clean the contact lenses well enough to fully kill all the infectious agents that are present on the contact lenses. As such, the FDA Ophthalmic Devices Panel which met on June 10, 2008, has recommended elimination of the No Rub instruction on all soft contact lens solutions. The FDA felt that the failure to manually rub the contact lenses with solution during the cleaning and disinfection procedure increases the incidence of Acanthamoeba and Fusarium keratitis infections. They further concluded that the increased incidence of Fusarium infections were largely due to poor compliance in cleaning the contact lens case, and poor hygiene in handling the contact lenses.

Another study performed on Acanthamoeba patients in Chicago concluded that wearers were reusing their solution, and failed to rub the lenses during cleaning, in addition to poor contact lens case hygiene. The FDA panel members all agreed that rubbing the lenses while cleaning should be included in the solution instructions, but did not determine the time required that the lenses must be rubbed. Further, the process of rubbing the contact lenses resulted in a decrease in the number of microbes on the contact lens surface.

In short, contact lens success relies on maintaining a clean, hygienic case, as well as digitally rubbing the lenses during the cleaning procedure. Following these simple steps will assure the wearer a healthy, infection free experience.

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