Fight Against RK

"People who are just now jumping on board (PRK) are not giving it it's proper respect, and we're going to wind up with a fair number of less than good results, and refractive surgery is going to get another black eye like it did in the 80s."

Ocular Surgery News, 1985, Volume 3 Number 17

"From the inability to let well enough alone; from too much zeal for the new and contempt for what is old; from putting knowledge before wisdom, science before art, and cleverness before common sense; from treating patients as cases, and from making the cure of the disease more grievous than its endurance, good Lord, deliver us."

Sir Robert Hutchison, 1871-1960, BMJ 1953

"Since its introduction to the United States, radial keratotomy has been shrouded by controversy among the ophthalmic community."

Dr Walter J Stark, Anterior Segment Surgery - 1987



Maine Eye Center

Lowell Street Portland, Maine 04102

(207)774-8277 1-800-545-6066 FAX (207) 871-1415

A. Jan Berlin. M.D.. F.A.C.S.

Ophthalmic Plastic lacrimal and Orbital Surgery

WHY I WILL NOT HAVE RADIAL KERATOTOMY

Radial keratotomy (RK) is a surgical procedure in which deep (90% of entire corneal thickness) incisions are made in the cornea in order to flatten it and reduce myopia (nearsightedness). Proponents of this procedure claim excellent results, but often fail to detail the risks.

Five years after surgery, only 36-60% of operated eyes see 20/20 without glasses. Because of this failure to achieve 20/20 vision in a large percentage of patients, RK proponents have accepted 20/40 as their criterion for "success." Using this relaxed standard, the percentage of "successfully" operated eyes (seeing 20/40 without glasses five years after surgery) increases to 75-88%. Almost never mentioned are the 3-5% of patients whose vision after RK cannot be corrected to the best pre-operative vision even with glasses or contact lenses.

Approximately one third of RK patients can expect an increased need for glasses when their pupils are dilated-such as occurs with night driving. (3) The effect of RK continues with time and tends to switch clients from nearsighted to farsighted. At four years after RK, approximately one of four patients will continue to drift into hyperopia (farsightnedness). There is no evidence that this trend will subside-and if it continueos, some patients will experience a visually incapacitating (without glasses or contact lenses) 4.0 diopter hyperopia 40 years after a "successful" RK.

RK eyes rupture along the incisions. Multiple cases have been reported in which RK patients were struck in the eye and the RK incisions broke open. The fact that some of these wound ruptures have occurred ten years after RK suggest that an RK eye will never regain full strength. Animal experiments have shown that the RK eye will rupture with half the blow required to rupture an unoperated eye. 

RK complications may be temporary (pain, glare, visual fluctuations) or permanent (persistent glare, fluctuation in vision, overcorrection, undercorrection, loss of best-corrected visual acuity, double vision, loss of fine depth perception), may require further surgery (cataract, ptosis), and may be potentially blinding (perforation of the cornea with subsequent infection, epithelial ingrowth).  

But doesn't all eyesurgery have complications? Yes,however when surgery for glaucoma, cataract, cancer, etc. is contemplated, the risk of damage to the eye from the surgery is carefully weighed against the risk to vision without the surgery. The risks and benefits are fully discussed with the patient before surgery. The patient gives an informed consent to undertake the risk inherent in the surgery in an attempt to manage the underlying disease state. 

Radial keratotomy can present significant risks, especially structural weakening of the eye. There is almost no risk in correcting one's vision reliably with glasses or contact lenses. RK is strictly a cosmetic procedure, performed on healthy eyes in young adults with many years ahead to live with complications. Would I have RK on my eyes? No,I will not undergo surgery for an uncertain outcome, risk losing the clarity of my vision with glasses, and weaken my eyes forever.

With acknowledgement to Paul F. Vinger, M. D.

 

Why I Don't Do Radial Keratotomy

Radial keratotomy has a significant risk, especially in that the eye is structurally weakened. There is no risk at all from not doing the surgery; the person's vision can be improved much more reliably with glasses or contact lenses. RK is strictly a cosmetic procedure, done to healthy eyes on impressionable young adults who have a long time to live with complications.

Potential RK candidates should realize that RK advertising is designed by marketing professionals whose only goal is to generate more procedures for the surgeon. In their terminology, you are considered a "close" when you sign for the surgery.

At about $1000 per eye, the surgeon has a tremendous financial motivation to minimize the risk and maximize good results.

Would I have RK on myself? Do you think a guy from Jersey would pay $2,000 to have pain with uncertain outcome, the risk of losing an eye, and the probability of weakening my eye forever to make somebody else rich?

I don't do radial keratotomy because I won't suggest to you what I wouldn't have done to me.

References:

Paul F.Vinger,,NlD.


Medical News

December 27, 1985

Caveat emptor tops the eye chart for radial keratotomy candidates

Since it's introduction into this country (JAMA [MEDICAL NEWS) 1981;245:897-900), radial keratotomy- the ocular surgical procedure that aims to correct myopia by means of 4, 6, 8, or 16 symmetric corneal cuts, has been performed on nearly 150,000 Americans eager to shed their spectacles and contact lenses.

According to many speakers at the annual meeting of the American Academy of Ophthalmology in San Francisco, radial keratotomy is an elective operation that people often choose because they see it widely advertised. Results of the Prospective Evaluation of Radial Keratotomy (PERK) study presented at last year's academy meeting (JAMA [MEDICAL NEWS) 1985; 253:1l03-1104)-and now amended after two years of the National Eye Institute-sponsored investigation (Ophthalmology; in press)-show that, while there are many reported successes, there also are numerous patients who have not been helped.

Now, for the first time, there are confirmed reports that some patients have been harmed.

Denis M. O'Day, MD, chief, Corneal and External Disease Service, Vanderbilt University Medical Center, Nashville, presented to academy members information about a cluster of 13 cases (none of them included in the PERK study) in which complications leading to visual impairment developed after radial keratotomy. Three eyes became legally blind.

All of the patients had the surgery elsewhere and all but one, who was seen in 1983, were referred to the Vanderbilt consultative service during the past year. O'Day and colleagues divide the complications into two categories: those known to be associated with any eye surgery or drug therapy for eye disease, and those that appear to be unique to radial keratotomy.

In the first group:

• Two patients developed optic atrophy in one eye after a retrobulbar injection of anesthetic preceding the radial keratotomy procedure traumatized the optic nerve. The day after surgery, they could see only hand movements, and two years later their vision hasn't changed.

Two patients developed cataracts. In one, radial keratotomy had been performed on both eyes at the same time, despite the fact that many ophthalmologists recommend waiting at least a year after the first eye is done, and when the patient was treated for six months with topical steroids postoperatively, posterior subcapsular lens opacity developed in both eyes. Twenty months after surgery, the patient suffers diplopia and wide fluctuation in visual acuity that is extremely difficult to correct with spectacles or contact lenses.

The second patient had the surgery on both eyes two months apart and developed a cataract in one eye the day after the operation. O'Day reports that this patient, who felt intense pain in the eye during the procedure and for about eight hours afterward, was told by his surgeon that "the knife slipped," resulting in a perforated lens. Various attempts have been made to improve the patient's vision, but O'Day says "he has refused further refractive surgery for fear of the result."

• One patient developed a retinal detachment after four months of continuous therapy with echothiophate iodide (generally used to treat glaucoma, of which O'Day says he saw no evidence) that was given to promote visual improvement after the radial keratotomy procedure left him with hyperopic and deteriorating vision. The patient now has an anisometropia (marked difference in refraction between the two eyes) of 8 diopters, which causes severe visual confusion, and diplopia and has refused surgery on the other eye.

• One patient developed Staphylococcus epidermidis endophthalmitis in one eye after bilateral radial keratotomies were performed for the second time in five months; the first procedures had failed to correct the patient's myopia. The infection responded to topical drug therapy, but since the second operation changed myopic vision only in the uninfected eye, the patient is left with severe anisometropia.

• One patient developed a corneal ulcer due to infection with Pseudomonas aeroginosa in one of the 16 radial incisions in her eye two years after radial keratotomy was performed. With treatment the ulcer gradually healed, but the patient's visual acuity, which had been 20/25 before surgery, was worsened to 20/50.

As Steven G. Kramer, MD, PhD, director, Department of Ophthalmology, University of California, San Francisco, School of Medicine, commented in a discussion following O'Day's presentation: "All of these complications seem significant and none would have occurred if the patients had not elected to undergo surgery for their myopia."

O'Day's second group of cases, which had complications he and his colleagues consider unique to radial keratotomy, overlaps the first. He reports that in 11 of the 13 patients, complications included failure to reduce myopia, aggravated by the induction of fluctuating vision, excessive glare, diplopia, and astigmatism, plus marked undercorrection, overcorrection, or severe anisometropia.

Another presentation at the meeting provided details of a four-year follow-up study of 79 patients (not in the PERK study) who underwent 109 radial keratotomy procedures. Michael R. Deitz, MD, clinical assistant professor of ophthalmology, University of Missouri-Kansas City School of Medicine, and Donald R. Sanders, MD, PhD, associate professor of ophthal- mology, University of Illinois at Chicago College of Medicine, have published these results (Arch Ophthal 1985;103:782-784 ).

In this study, Deitz and Sanders confirmed their earlier observation that in many cases radial keratotomy results in overcorrection that grows worse with time. In almost one third of the cases, they found significant (>1.0diopter) progressive hyperopia. "Most disturbing," they say, "is the apparent lack of correlation between this demonstrated progressive hyperopia and any of the factors known or thought to affect refractive outcome."

Walter J. Stark, MD, professor of ophthalmology and director of the Corneal Service at the Wilmer Institute, Johns Hopkins University, Baltimore, told JAMA MEDICAL NEWS: "This is one of the major concerns, because young people in their early 20s who are overcorrected might still be pretty happy with the result of the operation. They can see fairly well right now, but as they get older and their eyes lose the ability to accommodate-while the progressive effect continues, they're going to grow more and more unhappy. Instead of being able to go without eyeglasses or contact lenses, they're likely going to require two pairs of glasses to correct their visual defects."

Stark says that at this time Johns Hopkins' ophthalmologists are advising their patients against having radial keratotomy until longer term follow-up studies show whether the operation is safe and effective. "In addition to the complications discussed in Dr O'Day's study, which occur rarely," Stark says, "it appears to us from the Deitz and Sanders study and the new PERK data that this operation has many undesirable effects."

Another physician who presented evidence at the academy meeting of optical problems after refractive surgery was Perry S. Binder, MD, director, Ophthalmology Research Laboratory, Sharp Cabrillo Hospi- tal, San Diego.

Binder reviewed the literature concerning complications and their likely causes that occur in the numerous types of refractive corneal surgery. (The variety of such surgery, which began in the late 1970s, is made clear in a recent article entitled ,"Making Sense of 'Keratospeak' " [Arch Ophthal1985;103:1472- 1477] by George O. Waring III, MD, chair of the PERK study). The complications reported by Binder are similar in all of the procedures, and those he found in patients who had undergone radial keratotomy are similar to the ones found by O'Day.

"Since the majority of the refractive procedures operate on eyes that can be corrected to 20/20 acuity ~ [with glasses or contact lenses]," Binder says, "any complications which affect vision are considered significant."

Binder found that the most frequent optical complication after all refractive surgical procedures is under and overcorrection. He says: "Bilateral undercorrection in radial keratotomy does not produce a significant handicap to the patient. although approximately 30% to 40% of the eyes will require some form of visual correction [contact lenses or spectacles] ...

"Overcorrection can be corrected with spectacles or contact lenses. However, a major problem occurs for myopic patients who have a significant overcorrection. Significant anisometropia can produce severe depth perception disturbances. If the patient is unable to tolerate contact lenses, which is likely, since patients usually undergo the procedure to eliminate contact lenses, the alternative of spectacles may not provide significant relief. Such overcorrected radial keratotomy cases may need to undergo additional refractive surgical procedures. Unfortunately, there is no clinical experience that has been published for the treatment of the over or undercorrected case."

In a small percentage of cases, Binder says, all of the refractive corneal procedures can produce a permanent reduction in best corrected vision. "Possible causes of decreased vision following radial keratotomy include an improper optical zone location or incisions through the visual axis. An intrastromal corneal abscess within the keratotomy wounds can produce scarring and can degrade the visual image by induced irregular astigmatism."

Because all of the refractive surgical procedures reshape the front curvature of the cornea, they can interfere with the ocular surface epithelium, Binder explains. And because the surgery increases corneal thickness by the addition of scar tissue or by swelling of the corneal stroma, glare and Light sensitivity can result. Many people who undergo radial keratotomy complain of glare and photophobia in the first weeks or months after surgery, Binder says, but only 5% or less do so by the end of one year.

Another complaint after radial keratotomy is fluctuation in acuity, with vision being best in the morning and deteriorating throughout the afternoon and early evening, or vice versa. This problem is a major reason for the recent armed forces directive banning acceptance of persons who have had radial keratotomy.

For example, Col Thomas J. Tredici, MD, chief of ophthalmology at the School of Aerospace Medicine, Brooks Air Force Base, San Antonio, Tex, recently said: "Fluctuating vision is devastating for people involved in aviation. A pilot can't look at his squadron commander and say: 'I can't go now but my sight will be 20/20 by 2 o'clock'"(AirForceTimes Oct 28, 1985, P 19).

According to Binder, fluctuating vision that occurs after radial keratotomy is thought to be due to such factors as changes in intraocular pressure and/or fluctuation in corneal curvature throughout the day, the effects of eyelid pressure on corneal curvature, and a delay in wound healing. It can be treated, he says, "with several pairs of spectacles, contact lenses, or may require corneal transplantation."

Binder concludes that "many of the optical complications following radial keratotomy are due to technical problems such as too many incisions, incisions within the optical zone, decentered optical zones, crossing incision with epithelial cyst formation, redeepening procedures producing wide corneal scars, and astigmatism procedures performed in the incorrect meridian. Careful attention to surgical detail, decrease in the number of incisions , and using the largest possible optical zone, may decrease the number of optical problems that result from radial keratotomy.

(Meanwhile, during the academy meeting, several groups of ophthalmologists were calling spur-of- the-moment press conferences to dispute the cautionary examples saying their own radial keratotomy results were uniformly excellent or nearly so and distributing brochures that appeared to contradict the views of the speakers. For example, one group touted a resort-based training session with a brochure "announcing a two day intensive clinic giving you the skills and confidence to perform radial keratotomy" that promised: "In two days, you can transform your practice and enhance your career."

(A spokesman for the American Academy of Ophthalmology emphasizes that the academy still classifies the operation as an investigational procedure, noting this is the reason precise figures are not available regarding its cost and the number of ophthalmologists performing it. From the advertisements, one can infer that the cost, usually not covered by third-party payers, varies from $1,500 to $2,500 per eye, which amounts to $5,000 for both eyes, assuming no need for further corrective procedures. How many physicians are "enhancing" their careers is unknown.)

The PERK study's Waring, who is also professor of ophthalmology at the Emory Eye Center of Emory University School of Medicine, Atlanta, stresses radial keratotomy's lack of predictability, noting that it is impossible to know who will show stable improvement and who will show significant and possibly adverse changes in vision as time goes by. Furthermore, he says, the surgery appears to offer the greatest chance of better vision to patients whose myopia is slight. "The patient who has to wear glasses as thick as Coke bottles and who expects to do without glasses or contact lenses at all [after this operation] is believing in a myth," Waring says. 

Despite the preponderance of somewhat myopic patients who do well in the first year following radial keratotomy, O'Day says, "the fact remains that there are a number who will suffer significant ill effects." Although the number of patients in his study is small, he adds, the findings emphasize two important points: First, because radial keratotomy is a major surgical procedure on the cornea, it is prone to the same complications that can mar the results of any ocular surgical procedure. Second, there exists a group of patients whose visual impairment is a direct result of radial keratotomy.

"It is indeed disturbing to realize," O'Day adds, "that we may be encountering a new iatrogenic disease .... Patients with a previously intact visual system have acquired a disability that in most cases has no ready solution. Their suffering is very real, as is their anguish over what they now perceive as their own misplaced confidence in this procedure.

''Particularly unfortunate are those patients who underwent radial keratotomy in one eye with a disastrous result," he points out, because they refuse further surgery and "it is doubtful that any appreciated fully before surgery the consequences of an erroneous refractive result or the dilemma posed by the unoperated second eye. The data from the PERK study and others now indicate that our ability to predict such eases in advance is lacking."

In an interview, O'Day said: "Many ophthalmologists feel that radial keratotomy is not a good procedure, but they don't know how to advise their patients."

The consensus seems to be that while research and development of the radial keratotomy procedure may make it safer and more predictable in the future, at present, as Waring states: "Since it's now a product for sale, people need to have a buyer beware attitude." -by ~ARSHA F. GOLDSMITH


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