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Up Front | Sep 2002

Letters

The following refers to two articles written by Adam B. Krafczek Jr, Esq, entitled “Anatomy of a Lawsuit” and “Defense Claims Dr. Machat ‘Dropped a Bombshell' in Post vs. UPI Lawsuit,” that appeared in our July/August 2002 issue.

Editor,
I have never seen a journal article more informative and useful than Adam Krafczek's “Anatomy of a Lawsuit” in the July/August 2002 issue. It is unfortunate but true that the facts and issues Mr. Krafczek elucidates are more relevant to the American refractive surgeon than any mere medical breakthrough.

The legal process itself is formidable; it is designed to be hard to read and understand, dry, convoluted, drawn out, repetitious, and numbingly boring. Mr. Krafczek made the trial process clear and easy to follow, and his reports and characterizations of complex and detailed testimony seemed fair, readable, and complete. By teasing out the drama of the case for us, and clearly laying out the crucial facts and issues of this trial, he did the medical profession a great service in a number of ways.

First, the actual contentions at trial are important to patient assessment: pupil-size measurement, informed consent, and the evaluation of patients' subjective complaints (and our current inability to objectively refute them).

Second, the very massiveness and tedium of the legal process has always made it inaccessible to the lay physician. Who has the time or inclination to read all that stuff? It is that inaccessibility that those inclined to pervert the process (some of whom are in the medical business) have always been able to count on for cover. Knowing that articles of this sort will be knowledgeably written may, in the future, help budding snakes in the grass to at least confine themselves to the truth. Finally, I admired the cool and balanced tone of the subsequent article about the Snyder trial's bizarre and darkly hilarious denouement. I can only say, were you lying then, or are you lying now?

Keep up the good work.
WILLIAM I. BOND, MD
Pekin, Illinois

Dear Editor,
If there is an award in ophthalmology similar to a Pulitzer, Adam Krafczek deserves one for his coverage of the entire fiasco in Tucson—amazing writing, just spectacular. Easily the most exciting and informative reading I've done this summer. Seriously.

STEPHEN Coleman, MD
Albuquerque, New Mexico

IMPORTANCE OF PUPIL SIZE
The following reader/author exchange refers to an article written by James J. Salz, MD, entitled “The Importance of Pupil Size” that appeared in our July/August 2002 issue and continues these authors' discussion from their June 2002 article entitled “Point/Counterpoint: Is Pupil Size Important in Refractive Surgery?”

Dr. Salz,
It is with great interest that I read your article regarding the importance of pupil size. You are to be commended on your extensive history involving refractive surgery. However, I would urge extreme caution in utilizing anecdotal information derived from a small sample size, nondeductive reasoning, and patient/physician bias to arrive at your stated conclusion. If anything can be concluded from your retrospective series of a limited number of cases, it is that there is a very weak, noncompelling connection between subjective nighttime visual complaints, pupil size, and modern excimer laser optical/treatment zones.

In all four patients, you describe utilizing the LADARVision excimer platform and LADARWave. In each of the first three patients, you described optical/treatment zones equal to, nearly equal to, and greater than the patients' measured scotopic pupil. In all three cases, the patient complained of nighttime visual symptoms, which were minimized by the miotic effect of Alphagan. You describe the fourth patient as having pupils larger than the optical zone utilized for treatment but “completely satisfied” with her night vision.

Your observations and conclusions regarding the importance of pupil size in relation to patient's subjective night vision complaints merit serious scientific investigation. You assume that increased RMS values for both spherical aberration and coma explain a significant component of the patients' complaints of poor night vision, but this is unsupported in the scientific literature. It has been demonstrated that increased spherical aberration can be measured with larger pupil sizes in virgin eyes. However, your application of this finding to your patients' subjective complaints is a tenuous conclusion.

I would also caution against drawing any conclusions from wavefront data generated from nonvirgin eyes, since the wavefront device utilized was not designed for that purpose and may provide significant artifact in the measurements. Per our Point/Counterpoint article, some recent studies have not supported a correlation or association between pupil size and modern excimer optical zones.

In your conclusion, you suggest measuring pupil size carefully and making ablation diameters as large or larger than scotopic pupil size in order to reduce, but not eliminate, night vision problems. Your suggestion lacks any strong scientific basis and may ultimately harm large numbers of refractive surgery patients by removing corneal tissue that may be necessary for long-term structural integrity. Most long-term data involves optical zones of 5.5 to 6.0 mm and microkeratome technology that has historically produced significantly thinner-than-predicted corneal flaps (automated corneal shaper). Modern microkeratomes that produce significantly thicker flaps in conjunction with modern excimer platforms that allow surgeons to use larger optical/treatment zones (which have not been rigorously researched) may result in an increased incidence of ectasia.

Because there are no formal mechanisms for reporting this undesirable side effect of LASIK and deep stromal ablation PRK/LASEK, it may take 2 to 4 years (as with the PERK study) to clarify the potential risk increased-depth corneal stromal ablations will present to patients. Since you acknowledge that increased ablation diameters may not eliminate night vision problems, I would urge tight adherence to rigorously tested and researched modern optical zones and the avoidance of recommendations based on pseudoscience.

SAM OMAR, MD
Orlando, Florida

Dr. Omar,
I am pleased to see that you read the article. You make several valid points, and I agree with many of them. There is no doubt that we need a true study utilizing all of the measuring techniques we now have available: infrared pupil measurements, wavefront measurements, contrast sensitivity, and detailed questionnaires about patients' satisfaction with their night vision. The recent FDA panel's approval of the LADARVision CUSTOMCORNEA system for treating spherical myopia was partly based on the fact that these patients had a lower rate of induced higher-order aberrations and were somewhat more satisfied with their results. I hope that we will eventually have true scientific answers about the relationships between pupil size, ablation diameter, blend zones, customized versus non-customized ablations, and patients' complaints about their night vision.

Our ongoing debate, which most readers have fortunately been spared, unless they are “keranetters,” simply comes down to the fact that I think that patients with large pupils are potentially at greater risk for night glare and halos, and you think the “pupil is moot.” My article reflects my opinion and is not peer reviewed or statistically valid. It is a retrospective analysis of a few select patients who were potentially at risk, what I did, and how they turned out. I thought that the wavefront measurements after LASIK were interesting and, for the most part, correlated with their symptoms.

To me, the fact that making the pupil slightly smaller greatly diminishes the nighttime symptoms and higher-order aberrations proves that pupil size is important. Although my article represents a small, retrospective study, the addendum to my article includes several references to data that well-respected refractive surgeons have published and presented at meetings, research that emphasizes the problems of increased nighttime symptoms in patients with large pupils and small ablation diameters. You have apparently dismissed these references and label all of this “pseudoscience,” but I feel that the points raised in the article are important and that ignoring them may represent “noscience.”

It is up to the readers to decide how to discuss this issue with their patients when evaluating them for LASIK. Is pupil size important, or is it “moot?”
JAMES J. SALZ, MD
Los Angeles, California
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