Changes in posterior corneal elevations after combined transepithelial photorefractive keratectomy and accelerated corneal collagen cross-linking: retrospective, comparative observational case series

BMC Ophthalmology

Research Article

Hun Lee¹  David Sung Yong Kang²  Jin Young Choi²  Byoung Jin Ha²  Tae-im Kim³  Kyoung Yul Seo³  Eung Kweon Kim⁴ 

[1] Department of Ophthalmology, International St. Mary’s Hospital, Catholic Kwandong University College of Medicine, Incheon, South Korea;The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, South Korea;Eyereum Eye Clinic, Seoul, South Korea;The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, South Korea;The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, South Korea;Corneal Dystrophy Research Institute, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, South Korea;

关键词: Posterior corneal elevations;    Transepithelial photorefractive keratectomy;    Accelerated corneal collagen cross-linking;    Scheimpflug tomography;    Best-fit toric ellipsoid;   

DOI  :  10.1186/s12886-016-0320-3

 received in 2016-05-27, accepted in 2016-08-01,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundTo compare the changes in anterior and posterior corneal elevations after combined transepithelial photorefractive keratectomy (PRK) and accelerated corneal collagen cross-linking (CXL) and after PRK.MethodsMedical records of 82 eyes of 44 patients undergoing either combined transepithelial PRK and CXL (PRK-CXL group) or transepithelial PRK (PRK group) were examined retrospectively. Changes in anterior and posterior corneal elevations were calculated by fitting an 8.0-mm diameter best-fit sphere and best-fit toric ellipsoid (BFTE) to the corneal shape with a fixed eccentricity of 0.4 using Scheimpflug tomography (Pentacam HR; Oculus Optikgeräte GmbH, Wetzlar, Germany) preoperatively and 6 months postoperatively.ResultsIn anterior corneal elevation, both groups demonstrated a similar trend of a forward displacement of peripheral anterior corneal surface and a backward displacement of central anterior corneal surface. In posterior corneal elevation, a forward displacement of peripheral posterior corneal surface was induced in both groups, along with a backward displacement of central posterior corneal surface, regardless of the calculation method. The magnitudes of displacement of peripheral and central posterior corneal surfaces were significantly smaller in the PRK-CXL group than in the PRK group. Moreover, the PRK-CXL group showed a backward displacement of posterior corneal surface at maximum corneal elevations when the BFTE was used as the reference surface.ConclusionsTransepithelial PRK combined with prophylactic CXL significantly reduced the magnitudes of displacement of peripheral and central posterior corneal surfaces, with the radius of the BFTE was set to 8.0-mm on the Scheimpflug tomography system.

【 授权许可】

CC BY   
© The Author(s). 2016