The LASIK industry & the FDA have conspired since LASIK's inception to purposely withhold information vital to the public in making a truly informed LASIK decision. With Lasikdecision.com, The hope is to show you what the industry and FDA would not and did not even think of doing until LASIK casualties started speaking out, and yet, they still did NOTHING.
Risk Assessment for Ectasia after Corneal Refractive Surgery PDF Print E-mail
Sunday, 07 October 2007 15:59

1: Ophthalmology. 2007 Jul 9; [Epub ahead of print]

Randleman JB, Woodward M, Lynn MJ, Stulting RD.

Department of Ophthalmology, Emory University, Atlanta, Georgia.; Emory Vision, Emory University, Atlanta, Georgia.

PURPOSE: To analyze the epidemiologic features of ectasia after excimer laser corneal refractive surgery, to identify risk factors for its development, and to devise a screening strategy to minimize its occurrence.

DESIGN: Retrospective comparative and case-control study.

PARTICIPANTS: All cases of ectasia after excimer laser corneal refractive surgery published in the English language with adequate information available through December 2005, unpublished cases seeking treatment at the authors' institution from 1998 through 2005, and a contemporaneous control group who underwent uneventful LASIK and experienced a normal postoperative course.

METHODS: Evaluation of preoperative characteristics, including patient age, gender, spherical equivalent refraction, pachymetry, and topographic patterns; perioperative characteristics, including type of surgery performed, flap thickness, ablation depth, and residual stromal bed (RSB) thickness; and postoperative characteristics including time to onset of ectasia.

MAIN OUTCOME MEASURES: Development of postoperative corneal ectasia.

RESULTS: There were 171 ectasia cases, including 158 published cases and 13 unpublished cases evaluated at the authors' institution. Ectasia occurred after LASIK in 164 cases (95.9%) and after photorefractive keratectomy (PRK) in 7 cases (4.1%). Compared with controls, more ectasia cases had abnormal preoperative topographies (35.7% vs. 0%; P<1.0x10(-15)), were significantly younger (34.4 vs. 40.0 years; P<1.0x10(-7)), were more myopic (-8.53 vs. -5.09 diopters; P<1.0x10(-7)), had thinner corneas before surgery (521.0 vs. 546.5 mum; P<1.0x10(-7)), and had less RSB thickness (256.3 vs. 317.3 mum; P<1.0x10(-10)). Based on subgroup logistic regression analysis, abnormal topography was the most significant factor that discriminated cases from controls, followed by RSB thickness, age, and preoperative corneal thickness, in that order. A risk factor stratification scale was created, taking all recognized risk factors into account in a weighted fashion. This model had a specificity of 91% and a sensitivity of 96% in this series.

CONCLUSIONS: A quantitative method can be used to identify eyes at risk for developing ectasia after LASIK that, if validated, represents a significant improvement over current screening strategies.

NOTE - This would suggest  that the 250 RSB rule is NOT safe. Why are they still using it and how are they getting away with it? This is an example of the LASIK industry ignoring medical literature and continuing to do business as usual, keeping the standard of care low and ignoring patients' best interest.