Have you ever tried to explain to someone what patients with varying degrees of severity of glaucomatous damage actually see? What kinds of functional limitations they encounter? How they cope with daily activities? Or substitute cataracts or macular degeneration or retinitis pigmentosa or myopic degeneration for glaucoma. What is it like to be faced with a decision to undergo surgery when you have one eye with split fixation and you're 80 years old? Should you take a chance on losing it all at one shot or hope your remaining field can outlive you? What kind of decisions should you make if you have most of your life in front of you? I have seen thousands of glaucoma patients in the last 20 years and still have trouble describing to others what it's like or trying (my latest challenge) to reconstruct the effects of glaucomatous damage on computer images using graphics programs.

I remember about 20 years ago, when DeWitt Stettin, then Chairman of the National Science Foundation, wrote a scathing editorial in the New England Journal of Medicine about how he had macular degeneration and saw some 15 department chairmen around the country, all of whom told him that his vision wouldn't get any worse, but no-one ever told him about any of the services available or about the existence of low vision aids. Some 10 years ago, Frank Newell wrote that, of the 15,000 ophthalmologists in the United States, a not insignificant percentage had first hand familiarity with eye disease yet, this notwithstanding, noted that there were almost no detailed subjective descriptions of the effects of these diseases written by professionals and issued a call for submissions to the American Journal of Ophthalmology. Nothing happened. I may have missed a lot in the literature, but the only paper I can quote off the top of my head is Mel Rubin's wonderful analysis of the decisions involved in deciding what refractive error to aim for when his cataract was removed.1 This article should be read by all ophthalmologists.

In this week's column, Dan Jewelewicz, a very bright and perceptive resident at Columbia, discusses the subjective effects of his own medical treatment and the decisions he faced in deciding the appropriate path for himself. I think you'll find it illuminating and would like to encourage others to submit their own experiences.

A little knowledge is a dangerous thing. As physicians, we engage in the routine practice of deciding what is best for our patients. The commendable physician makes these decisions with the patient's input, but ultimately our advice is perceived as "the final word." But what happens when we are our own patients? Weighing risks and benefits takes on an added dimension; knowledge may actually blur the distinctions among treatment options and render treating oneself exceedingly more difficult than treating others. Nonetheless, many physicians are placed in this situation, as I was after being diagnosed with pigment dispersion syndrome roughly one year ago. The decision-making processes concerning why and how to treat are complex; I thought I might share with the reader my opinions and experiences. My goal is not to provide a review of PDS, but rather to provide insight into treating this elusive condition.

I was first diagnosed during a routine contact lens fitting, when an astute ophthalmologist noted bilateral Krukenberg spindles. Subsequent exams revealed marked iris transillumination defects, dense trabecular pigmentation, IOP in the mid-twenties, non-glaucomatous discs (though admittedly difficult to evaluate given their myopic, and thus tilted nature), and "normal" visual fields. Being the somewhat compulsive sort, I immediately raced to the library and voraciously learned all that I could about PDS. Common terms such as "glaucomatous change" and "field loss" took on a different meaning as I imagined myself tapping down the street with a cane. Once I had finished wantonly over-reacting, I consulted with several respected colleagues and decided it would indeed be best to intervene. Rates of progression to glaucoma reported in the literature vary widely: initial studies suggested 35%.2-4 More recent studies suggest that the proportion of patients with PDS who develop glaucoma may actually be much lower, as PDS may remain undetected in many people and never approach clinical significance.5 Nonetheless, the profound visual morbidity from glaucoma I see daily in practice prompted me to seek treatment.

There is, to date, no "standard of care" in treating pigment dispersion syndrome. In my particular case, I was concerned with arresting or reversing the pathophysiologic process in order to prevent visual field loss. Campbell6 suggested that PDS results from excessive mechanical rubbing between zonular fibers and the peripheral iris. The liberated pigment deposited in the trabecular meshwork and phagocytized by trabecular cells may result in an adverse effect on aqueous outflow. Thus, it makes intuitive sense that preventing this contact may lessen the likelihood of pigment dispersion. A miotic is thus an ideal choice...for some.

I initially tried 1/2% pilocarpine, which increased my already inconvenient myopia of roughly 3.5 diopters to a monstrous and fluctuating 8 or 9 diopters. Even 1/8% proved entirely intolerable. I drove home from work one day in trial frames attempting to surmount this side effect, but to no avail (fortunately I arrived home in one piece). Soon afterwards I began using Ocuserts, first in my left eye, then in both, with moderate success. Ultrasound biomicroscopy demonstrated a marked convexity in contrast to the concavity present before treatment. In my opinion, Ocuserts are an excellent first-line therapy for patients still in the active pigment dispersion phase of the disease. The pilocarpine reverses the iris concavity, eliminating iridozonular contact and hopefully arresting the pathophysiologic process. Furthermore it lowers IOP by increasing aqueous outflow, thereby promoting clearing of pigment and recovery of trabecular function. The induced accommodative spasm is much milder and more constant that which occurs with the use of pilocarpine drops, resulting in a more tolerable increase in myopia (of up to approximately 1.50 diopters in my case).

After repeated refractions throughout the 5-day cycle of Ocusert use, however, I found that the myopia also fluctuated and consisted of a cylindrical component as well. The induced myopia was always worst immediately after instillation, though this was easily overcome by placing the unit in my eye before going to sleep. The myopia was also significantly worse upon awakening, even from a nap, and during periods of ocular irritation, as evidenced by a not-so-brief bout of conjunctivitis (I suspect these effects may be due to a change in the diffusion rate of pilocarpine through the copolymer membrane of the unit. Hypersecretory states such as conjunctivitis may alter tear osmolarity and affect delivery). Although significantly better than pilocarpine drops, I still found the myopia inconvenient - not debilitating, but bothersome. I added 0.5 diopter of minus to my current spectacle correction, but still found the fluctuating nature of the myopia awkward. Many patients tolerate Ocusert fabulously, but I was bothered enough to search for a more tolerable treatment and still maintain my goal of reversing iris configuration.

Dapiprazole, an alpha-adrenergic antagonist, is an option that induces miosis by relaxing the dilator muscle without affecting the ciliary body, thus inducing no accommodative spasm. Although theoretically useful, it has been reported to cause burning and conjunctival hyperemia with chronic usage, and I elected not to use it.

Although by no means an accepted and proven treatment, laser iridotomy has shown promise in reversing iris configuration in certain patients. It has been suggested that a reverse pupillary block exists in PDS.7 Increased iridolenticular contact inhibits the equilibration of aqueous between the anterior and posterior chambers. This increases the iris concavity and iridozonular contact, facilitating pigment dispersion. Iridotomy creates an additional pathway for aqueous equilibration and allows the iris to assume a more planar configuration. Further research is undoubtedly necessary to determine who will benefit from this procedure, and failures have been reported. Nonetheless, it is a promising procedure and I elected to undergo argon laser iridotomy in my left eye. This was "successful" in that it changed the gonioscopic appearance of the iris from concave to planar (figure). Furthermore, dilation no longer resulted in florid dispersion and subsequent IOP rise as it did prior to iridotomy. Though greatly beneficial, this procedure was not without untoward side effects. I do see a flash of light with each blink even though the iridotomy site is beneath the upper lid. This is barely apparent. More perceivable is a series of thin white vertical lines of light that is most obvious in my temporal field when driving at night and clearly related to the oncoming headlights. It is not debilitating, but present nonetheless and patients considering iridotomy should be warned of such possible visual phenomena. I eventually chose to undergo a similar iridotomy in my right eye, though smaller and more superior. This has resulted in no significant visual sequelae.

Other aspects of my treatment have been to avoid jarring exercise such as jogging, which has been shown to disperse pigment in susceptible individuals and can result in an IOP rise, which can be prevented by pretreatment with pilocarpine, but only partially by laser iridotomy.8-10 It may be prudent to advise patients with iridotomies to use low-dose pilocarpine before extensive periods of jarring exercise, or at least to examine them after such exercise to determine whether or not pigment is liberated and/or IOP rises.

Much remains to be learned about PDS. Tolerable pharmacological agents that induce miosis without accommodation would be tremendously beneficial. Determination of prognostic indicators to predict who will benefit from laser iridotomy would be highly advantageous. Prolonged accommodation may predispose to dispersion in susceptible individuals.11 Should myopic patients with PDS read with their glasses on? My knowledge of this condition - albeit little compared to what remains to be learned - has influenced my treatment. However, it may indeed have been less taxing to simply accept the advice of my ophthalmologist! I hope that my experiences offer some insight into treating others with PDS, and encourage the reader to search for new treatment modalities. I, for one, will certainly be thinking of new means to diagnose and treat this condition. After all, necessity is the mother of invention.

1. Rubin ML. A case for myopia. Surv Ophthalmol 1991;35:307-310.

2. Migliazzo CV, Shaffer RN, Nykin R, Magee S. Long-term analysis of pigmentary dispersion syndrome and pigmentary glaucoma. Ophthalmology 1986;93:1528-1536.

3. Farrar SM, Shields MB, Miller KN, Stoup CM. Risk factors for the development and severity of glaucoma in the pigment dispersion syndrome. Am J Ophthalmol 1989;108:223-229.

4. Richter CU, Richardson TM, Grant WM. Pigmentary dispersion syndrome and pigmentary glaucoma. A prospective study of the natural history. Arch Ophthalmol 1986;104:211-215.

5. Ritch R, Steinberger D, Liebmann JM. Prevalence of pigment dispersion s yndrome in a population undergoing glaucoma screening. Am J Ophthalmol 1993;115:707-710.

6. Campbell DG. Pigmentary dispersion and glaucoma: a new theory. Arch Ophthalmol 1979;97:1667-1672.

7. Karickhoff JR. Pigmentary dispersion syndrome and pigmentary glaucoma: a new mechanism concept, a new treatment, and a new technique. Ophthalmic Surg 1992;23:269-277.

8. Haynes WL, Johnson AT, Alward WLM. Inibition of exercise-induced pigment dispersion in a patient with the pigment dispersion syndrome. Am J Ophthalmol 1990;109:599-601.

9. Haynes WL, Johnson AT, Alward WLM. Effects of jogging exercise on patients with the pigment dispersion syndrome and pigmentary glaucoma. Ophthalmology 1992;99:1096-1103.

10. Haynes WL, Alward WLM, Tello C, et al. Incomplete elimination of exercise-induced pigment dispersion by laser iridotomy in pigment dispersion syndrome. Ophthalmic Surg Lasers 1995;26:484-486.

11. Pavlin CJ, Harasiewicz K, Foster FS. Posterior iris bowing in pigmentary dispersion syndrome caused by accommodation. Am J Ophthalmol 1994;118:114-116.

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