Here is a case report of a woman who developed ectasia following LASIK due to inaccurate flap cut.

The surgery was planned with an estimated flap thickness of 150 um.

From the full-text:

"Subjective optical pachymetry at the slitlamp estimated flap thickness to be approximately 200 um."

J Cataract Refract Surg. 2005 Aug

Reversal of laser in situ keratomileusis-induced ectasia with intraocular pressure reduction.

Hiatt JA, Wachler BS, Grant C.

Boxer Wachler Vision Institute, Beverly Hills, California 90210, USA.


A 40 year-old woman had laser in situ keratomileusis for --7.75 --0.75 x 20 in the right eye. Preoperative examinations, including topography, pachymetry, and intraocular pressures (IOPs), were normal, and best spectacle-corrected visual acuity (BSCVA) was 20/20 in each eye. By 4 months postoperatively, the uncorrected visual acuity and BSCVA in the right eye had decreased to 20/40. Corneal topography of that eye was consistent with ectasia. One drop per day of timolol 0.5% (Timoptic XE) was prescribed. Five months postoperatively, the IOP had decreased and BSCVA and topography had improved. At 11 months, BSCVA returned to 20/20 and corneal topography normalized. Topographic difference maps were used to monitor corneal shape changes. In this case, early reduction in IOP completely reversed the ectasia.

The abstract does not reveal that ectasia returned when the patient was taken off pressure-lowering drugs.