The Dry Eye Zone

Rebecca's Blog

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4/25/08 FDA LASIK Hearing: Trivia and miscellaneous observations

On the merits of glasses

Dr. Jayne Weiss, chair of the Ophthalmic Devices Panel for the 4/25 meeting, kindly forestalled the inevitable press commentary on how many panel members were wearing glasses by pointing it out herself and challenging her colleagues to explain themselves. So why does Dr. Weiss (a LASIK surgeon) not get LASIK?

Two reasons:

First, I like my near vision. If I were to get LASIK, I would not be able to see up close without glasses anymore.

Second, I am not willing to put my eyes at ANY risk.



On financial conflicts of interest

By the end of the public hearing, this refrain was running through my head like a really bad but catchy country song:

Hello, my name is Dr. So-and-so.... and I'm a paid consultant to AMO....


For those who don’t follow this stuff, Advanced Medical Optics owns (a) VISX, the US market leader in excimer lasesrs (that’s the machine used to “reshape” corneas) and (b) IntraLase, the ‘hot technology’ of LASIK – a femtosecond laser which makes LASIK flaps without a blade.

I lost track of how many actually are AMO consultants, but I don't recall there being any ophthalmologists presenting during the public hearing who did NOT acknowledge any industry financial conflicts. If anyone has information contradicting that, please set the record straight for me.

That sort of stuff goes right over the head of today's media. All they hear are the half-page of credentials immediately after the name.

On bad science and unequal standards

The hearing had its high points and its low points.

One of the lowest of the lows was something about pupils, the significance of which the press could not possibly have picked up on and probably went right over the head of most of the attendees as well.

At least two presenters, Dr. Steve Schallhorn and Cmdr David Tanzer (I'll talk more about the latter in an other post about the role of the DOD in Friday's meeting) referred to one of Dr. Schallhorn's studies indicating pupil size is not predictive of vision quality/night vision disturbances. At the end of the meeting when chair Dr. Weiss was summing up changes agreed upon for the FDA's LASIK pages, she indicated that the warnings about pupil size need to be brought up to date with current literature.

What Dr. Weiss (with whom, incidentally, I was quite impressed throughout the proceedings) presumably was not aware of is that Dr. Schallhorn's pupil study has been completely discredited by numerous other studies and letters to the editor. Methodology for eliciting the dark-adapted pupil size of the study subjects is fundamental to the reliability of any such study and his numbers were simply indefensible in the context of the mean DAPD for each age group as established in the medical literature by national experts. I hope and expect that the interested experts will set her straight on this before they actually change - i.e. REMOVE or water down - a vital warning on the FDA website to people with large pupils.

What I found so ironic in this situation is that Dr. Weiss as chair of the ODP readily accepted and recommended to the FDA that they change their website language on the basis of a single study mentioned during the meeting.

At the same time, the ODP did not hesitate to brush off consumer advocate Paula Cofer's recommendation of a warning about a decrease in corneal keratocyte density with unknown long term complications. On what basis? That it was based upon a single study. Apparently if the study author, or the DOD, mentions it, it can safely be assumed to be prevailing science, while if a consumer mentions it, they don't know what they're talking about.

Lastly... and unrelated specifically to this hearing, but I mention it because it has always irked me exceedingly... is that whenever I've heard Dr. Schallhorn talk about this pupil size issue, (a) he maintains that his studies show that pupil size is not predictive of NVD complaints, YET nonetheless (b) he hastens to add that they ALWAYS measure dark-adapted pupil diameter anyway, but don't use that information in surgical planning. (Excuse me, but why measure it if you are perfectly convinced it is irrelevant and if you are not going to use it?)
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