Exposing the LASIK Scam

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 Post subject: VISX Clinical Trials Coverup
PostPosted: Thu Nov 17, 2005 11:39 pm 

Joined: Mon Nov 14, 2005 4:28 pm
Posts: 643
VISX Clinical Trials Coverup

http://www.ncbi.nlm.nih.gov/entrez/quer ... &DB=pubmed

Understanding pre-market approval and labeling differences of two leading customized ablation platforms: a call for reform at the FDA.
Wachler BS, Hiatt JA.
J Refract Surg. 2004 Sep-Oct;20(5):S588-92.

Excerpt from the full text:

VISX reported that 97.7% (84/86) of eyes had UCVA of 20/20 or better at 12 months. These 86 eyes represent only 24.5% of patients. Accountability is reported to be 95.6%,
despite the fact that 70.7% (248/351) of patients were labeled ?not yet eligible? for analysis at 12 months.
In the VISX trial, 13 eyes were excluded from the data analysis because they required retreatments (12 within the study, 1 outside the study) as these 13 eyes had UCVA of 20/32 or worse. Adding these eyes to the 12-month data, UCVA of 20/20 can be recalculated to be 84.8% of eyes (84/99) at 12 months; this is in contradistinction to the 97.7% reported with exclusion of these 13 eyes that saw 20/32 or worse without correction.
The addition of these 13 eyes still only accounts for 28.2% (99/351) of 12-month results from patients enrolled in the clinical trial; the refractive outcomes for >70% of the study population are not reported.

 Post subject:
PostPosted: Wed Dec 14, 2005 12:54 pm 

Joined: Thu Nov 24, 2005 9:06 pm
Posts: 297
VISX has been doing this for years!

July, 1999
FDA Opthalmic Devices Panel meeting to review
LASIK clinical trials for VISX

DR. BULLIMORE: "Thank you, Mr. Chairman. This is Mark Bullimore. I don't want to go into the data too much since both the sponsor and the medical officer have already given an excellent overview of that.
Like Dr. Mannis I believe the PMA is approvable with some conditions that relate to product labeling and the range of approval, but there are a number of things that I would like to bring to the Panel's attention for discussion.
The biggest is this issue of accountability, and Dr. Ferris has already raised this, and it already has had some discussion among the Panel. One characteristic of the PMA is the very variable accountability of these clinics. Overall the accountability is less than 75 percent at 3 months and less than 63 percent at 6 months, and if you look at the data, one surgeon actually enrolled 179 patients which actually represents 10 percent or more of the entire cohort but did not report any 3-month examination. So, at least in that particular surgeon's case there is no bias, but the sponsor addresses the issue by dividing the whole cohort into this PMA cohort and this remainder cohort.
I was, also, intrigued to note that of the three people who made presentations to the Panel, the three physicians, one of them wasn't included in the PMA cohort and a second actually just made the cut.
So, this is a constant source of concern for me because as indicated by Dr. Ferris, we know something about the people who do return for the visits, the follow-up visits, but we never know anything about the people who don't return. We can say that the PMA cohort that return are reasonably equivalent to the people in the remainder cohort, but the individuals that are included ultimately in both cohorts and taking the cohort as a whole we don't know anything about the 30-something percent who are not seen at 6 months.
So, the potential for patient bias or surgeon bias or investigator bias is considerable because of this at best mediocre accountability.
I was interested to hear the comment made that when you do compare the PMA cohort, that is the good clinics with the remainder cohort henceforth referred to as the great unwashed, that does suggest that there is some bias there on the part of the physicians, and I don't want to sort of target them or be accused of slander, but the fact of the data they are reporting, given their lower accountability is slightly better than the group, the PMA cohort, suggests that the bias actually runs in that direction. So, that is all I have to say about that, and we have an industry representative on the Panel, and I wouldn't expect that many of the investigators would get a call from Dr. Yaross for her own company's investigations given some of these rates of follow-up

 Post subject: Mediocre accountability denies patients informed consent
PostPosted: Sat Jul 22, 2006 9:15 pm 

Joined: Mon Jan 02, 2006 7:17 pm
Posts: 161
Because VISX has not been forthcoming about its outcomes and the univsersal loss of contrast sensitivity found in clinical trials, patients are denied informed consent for LASIK. Some day there may very well be a mammoth class action suit.

As the millions of LASIK patients age and develop age-related problems related to their refractive surgeries, the dung will surely hit the proverbial fan. We're talking about a segment of the population who can afford an expensive elective surgery. Will they also be more inclined to pursue litigation?

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