光学相干断层扫描客观测量角膜水肿时的角膜后散射

作     者：Simpson T.L. Fonn D. 齐翔云 

作者机构：Centre for Contact Lens Research Schoo l of Optometry University of Waterloo Waterloo Ont. N2L 3G1 Canada 

出 版 物：《世界核心医学期刊文摘（眼科学分册）》 (Digest of the World Core Medical Journals:Ophthalmology)

年 卷 期：2005年第1卷第2期

页      面：34-35页

学科分类：1002[医学-临床医学] 100212[医学-眼科学] 10[医学] 

主　　题：角膜水肿 客观测量 软性接触镜 对侧眼 戴镜 中央角膜厚度 基线测量 可重复性 消退期 程序分析 

摘      要：PURPOSE. To demonstrate that corneal light-backscatter can be measured object ively during corneal swelling by optical coherence tomography (OCT). METHODS. On e eye (randomly selected) of 20 non-contact-lens wearers (10 men and 10 women; mean age, 35.6 ±9.6 years) was patched during 3 hours of soft contact lens (SC L) wear. The contralateral eye acted as the control. Central corneal images were captured before and after SCL wear at 20-minute intervals over 100 minutes usi ng optical coherence tomography (OCT) to obtain corneal thickness and light-bac kscatter profiles. OCT backscattered light of the epithelial layer (decided by t he thickness measurements) and 10 equally divided layers of the remaining cornea were analyzed with a custom soft ware program. Two baseline measurements were t aken at different visits before lens wear to test the repeatability of light-ba ckscatter measurements. RESULTS. From two baseline measurements, repeated measur ements showed good repeatability of normalized backscatter results. Immediately after contact lens removal, total central corneal thickness increased significan tly by 13.8%±2.3%(mean ±SD) compared with baseline (P=0.0001, paired t-test ) and then decreased during the deswelling course. Corneal backscattered light c hanged significantly (repeated-measures ANOVA Re-ANOVA: F(50,950)=2.22, P=0. 0001) after lens wear, and a significant increase in backscatter was found in th e epithelial layer (36.4%) and the most posterior corneal layer (35.6%) immedi ately after lens removal (post hoc test, P=0.005). There was a strong correlatio n (r=0.9375, P 0.05) between the change in backscatter and corneal swelling dur ing the deswelling period. The backscatter recovery rate was approximately the s ame for both epithelial and posterior layers after lens removal. CONCLUSIONS. Li ght- backscattering analysis with OCT seems to be a promising and repeatable method of objectively measuring corneal backscatter. This study has demonstrated tha