Article

Surface ablation does not prevent ectasia in forme fruste keratoconus eyes in review

Review of a small series of eyes shows surface ablation procedures do not eliminate the risk of postoperative ectasia in eyes with forme fruste keratoconus, even in eyes without other ectasia risk factors.

Key Points

London- Ectasia can develop after surface ablation in eyes with forme fruste keratoconus (FFKC), and no identifiable features appear to protect against that event, according to the findings of a retrospective study.

"Surface ablation is increasingly being performed around the U.S. and other countries partly to avoid flap complications, but also to prevent ectasia," said Sheraz M. Daya, MD, director and consultant, Corneoplastic Unit and Eye Bank, Queen Victoria Hospital, East Grinstead, and medical director, Centre for Sight, London and East Grinstead.

"However, the questions of whether it eliminates or minimizes the risk of that complication and whether it is truly safe in patients with FFKC if they have thick corneas or flat corneas have not been answered," Dr. Daya said.

The review was based on eight eyes of four patients seen on referral for the development of ectasia between April 2002 and June 2005. Seven eyes had frank ectasia, whereas one had progression of FFKC that was not clinically significant as the patient retained good unaided vision. Six eyes had preoperative data available, and all were identified as having FFKC or pellucid-like changes on topography.

The eyes had undergone myopic LASEK or PRK, and the mean time to presentation afterward was 32 months. One case developed after 9 years, but all others occurred within the first 4 to 9 months.

"With the exception of the late-onset case, we do not think these eyes would have developed ectasia anyway even if they did not have refractive surgery," Dr. Daya said.

The features of the patients in the series provided the basis for the conclusions that a thick cornea, flat cornea, and age over 40 years probably do not reduce the risk of ectasia after surface ablation in eyes with FFKC. At the time of the refractive surgery, the patients had a mean age of 34 years; two were aged more than 40 years. Preoperative corneal thickness averaged 519 μm and exceeded 500 μm in five of the six eyes.

Preoperative keratometry averaged 45.1 D, with a minimum K reading of 42.75/43.00 D. Mean preoperative spherical equivalent (SE) was about –4.0 D, and mean tissue ablation depth was 100 μm with a range of 25 to 167 μm.

Upon presentation to Dr. Daya's center, the eyes had a mean SE of –1.6 D and more astigmatism than prior to their refractive surgery as measured by both refraction and keratometry. The mean K value was 44 D and mean corneal thickness was 461 μm.

Newsletter

Don’t miss out—get Ophthalmology Times updates on the latest clinical advancements and expert interviews, straight to your inbox.

Related Videos
Shehzad Batliwala, DO, aka Dr. Shehz, discussed humanitarian ophthalmology and performing refractive surgery in low-resource, high-risk areas at the ASCRS Foundation Symposium.
(Image credit: Ophthalmology Times) ASCRS 2025: Advancing vitreous care with Inder Paul Singh, MD
(Image credit: Ophthalmology Times) The Residency Report: Study provides new insights into USH2A target end points
Lisa Nijm, MD, says preoperative osmolarity testing can manage patient expectations and improve surgical results at the 2025 ASCRS annual meeting
At the 2025 ASCRS Annual Meeting, Weijie Violet Lin, MD, ABO, shares highlights from a 5-year review of cross-linking complications
Maanasa Indaram, MD, is the medical director of the pediatric ophthalmology and adult strabismus division at University of California San Francisco, and spoke about corneal crosslinking (CXL) at the 2025 ASCRS annual meeting
(Image credit: Ophthalmology Times) ASCRS 2025: Taylor Strange, DO, assesses early visual outcomes with femto-created arcuate incisions in premium IOL cases
(Image credit: Ophthalmology Times) ASCRS 2025: Neda Shamie, MD, shares her early clinical experience with the Unity VCS system
Patricia Buehler, MD, MPH, founder and CEO of Osheru, talks about the Ziplyft device for noninvasive blepharoplasty at the 2025 American Society of Cataract and Refractive Surgeons (ASCRS) annual meeting
(Image credit: Ophthalmology Times) ASCRS 2025: Bonnie An Henderson, MD, on leveraging artificial intelligence in cataract refractive surgery
© 2025 MJH Life Sciences

All rights reserved.