应用可视化角膜生物力学分析仪评估不同阶段圆锥角膜生物力学特征

doi:10.3760/cma.j.issn.1674-845X.2014.05.003

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Abstract

Objective To compare the corneal biomechanical properties of the corneas of keratoconic eyes and normal eyes using corneal visualization Scheimpflug technology （Corvis ST）， and to investigate the role of corneal biomechanical parameters in the diagnosis of keratoconus. Methods Ninety keratoconic eyes from 65 patients and 90 normal eyes from 90 participants were enrolled in this comparative study. Based on the Amseler-Krumeich keratoconus stages， the keratoconic eyes were divided into a mild group （46 eyes）， moderate group （23 eyes） and severe group （21 eyes）. Tomography and biomechanical parameters of all eyes were obtained with the Pentacam and Corvis ST， respectively. All parameters were compared between the keratoconic and normal groups. The correlation between deformation amplitude and anterior segment parameters was also analyzed. An independent t test， Wilcoxon rank sum test， ANOVA， nonparameter test were used. The receiver operating characteristic （ROC） curves were plotted to distinguish keratoconus from the normal cornea. Results The tomography and biomechanical parameters of the keratoconic eyes were significantly different from those of normal eyes except for the anterior chamber angle， first applanation length， highest concavity time， and peak distance. The deformation amplitude （area under the curve： 0.865） was the best predictive parameter， with a sensitivity of 84.5%， specificity of 75.6% and cut-off point of 1.14 mm. The diagnostic efficiency of the deformation amplitude increased with an increase in the severity of keratoconus. In both the normal and keratoconic groups， the deformation amplitude was negatively correlated with intraocular pressure， central corneal thickness， and corneal volume at 3 mm. The respective r values of the deformation amplitudes of the normal and keratoconic groups in regard to： intraocular pressure， -0.707 and -0.213； central corneal thickness， -0.219 and -0.357； and corneal volume at 3 mm， -0.212 and -0.27. All P values were <0.05. Conclusion Corvis ST offers an alternative method for measuring corneal biomechanical properties. The deformation amplitude has a high sensitivity for the diagnosis of keratoconus. The negative correlations with intraocular pressure and central corneal thickness deserve clinical attention.

Key words： Biomechanics Keratoconus Corneal visualization Scheimpflug technology Deformation amplitude

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	Articles by authors
	Tian Lei
	Wang Liqiang
	Meng Xiaoli
	Wu Ying
	Huang Yifei

Cite this article:

Tian Lei,Wang Liqiang,Meng Xiaoli等. Assessment of corneal biomechanical properties using corneal visualization Scheimpflug technology at different stages of keratoconus[J]. Chinese Journal of Optometry Ophthalmology and Visual Science, 2014, 16(5): 268-273.

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https://www.cjoovs.com/EN/10.3760/cma.j.issn.1674-845X.2014.05.003 OR https://www.cjoovs.com/EN/Y2014/V16/I5/268

[1]	Rabinowitz YS. Keratoconus[J]. Surv Ophthalmol，1998，42：297-319.
[2]	McMahon TT， Szczotka-Flynn L， Barr JT， et al. A new method for grading the severity of keratoconus： the Keratoconus Severity Score （KSS）[J]. Cornea，2006，25：794-800.
[3]	Shirayama-Suzuki M， Amano S， Honda N， et al. Longitudinal analysis of corneal topography in suspected keratoconus[J]. Br J Ophthalmol，2009，93：815-819.
[4]	Meek KM， Tuft SJ， Huang Y， et al. Changes in collagen orientation and distribution in keratoconus corneas[J]. Invest Ophthalmol Vis Sci，2005，46：1948-1956.
[5]	Gefen A， Shalom R， Elad D， et al. Biomechanical analysis of the keratoconic cornea[J]. J Mech Behav Biomed Mater，2009， 2：224-236.
[6]	Luce DA. Determining in vivo biomechanical properties of the cornea with an ocular response analyzer[J]. J Cataract Refract Surg，2005，31：156-162.
[7]	Saad A， Lteif Y， Azan E， et al. Biomechanical properties of keratoconus suspect eyes[J]. Invest Ophthalmol Vis Sci，2010， 51：2912-2916.
[8]	Shah S， Laiquzzaman M， Bhojwani R， et al. Assessment of the biomechanical properties of the cornea with the ocular response analyzer in normal and keratoconic eyes[J]. Invest Ophthalmol Vis Sci，2007，48：3026-3031.
[9]	Hon Y， Lam AK. Corneal deformation measurement using Scheimpflug noncontact tonometry[J]. Optom Vis Sci，2013，90： e1-8.
[10]	Zadnik K， Barr JT， Edrington TB， et al. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus （CLEK） Study[J]. Invest Ophthalmol Vis Sci，1998，39：2537-2546.
[11]	de Sanctis U， Loiacono C， Richiardi L， et al. Sensitivity and specificity of posterior corneal elevation measured by Pentacam in discriminating keratoconus/subclinical keratoconus[J]. Ophthalmology，2008，115：1534-1539.
[12]	Liu R， Chu RY， Zhou XT， et al. A compare study on cornea biomechanical properties in normal and keratoconic eyes[J]. Zhonghua Yan Ke Za Zhi，2009，45：509-513.
[13]	Choi JA， Kim MS. Progression of keratoconus by longitudinal assessment with corneal topography[J]. Invest Ophthalmol Vis Sci，2012，53：927-935.
[14]	Hong J， Xu J， Wei A， et al. A new tonometer—the Corvis ST tonometer： clinical comparison with noncontact and Goldmann applanation tonometers[J]. Invest Ophthalmol Vis Sci，2013，54：659-665.
[15]	Ambrósio RJ CDL， Ramos IC SRT， Pimentel LN RCJ， et al. Corneal biomechanical assessment using dynamic ultra high-speed Scheimpflug technology noncontact tonometry （UHS-ST NCT）： preliminary results. Presented at ASCRSASOA， San Diego， CA， March 25-29， 2011. Available at： http：//www.optomes.com.tr/TR/dosya/1-604/h/corvisstascrs2011final.pdf. Accessed February 15，2012.
[16]	Ucakhan OO， Cetinkor V， Ozkan M， et al. Evaluation of Scheimpflug imaging parameters in subclinical keratoconus， keratoconus， and normal eyes[J]. J Cataract Refract Surg，2011， 37：1116-1124.
[17]	Konstantopoulos A， Hossain P， Anderson DF. Recent advances in ophthalmic anterior segment imaging： a new era for ophthalmic diagnosis[J]. Br J Ophthalmol，2007，91：551-557.
[18]	Ortiz D， Pinero D， Shabayek MH， et al. Corneal biomechanical properties in normal， post-laser in situ keratomileusis， and keratoconic eyes[J]. J Cataract Refract Surg，2007，33：1371-1375.
[19]	Wolffsohn JS， Safeen S， Shah S， et al. Changes of corneal biomechanics with keratoconus[J]. Cornea，2012，31：849-854.
[20]	Dorronsoro C， Pascual D， Perez-Merino P， et al. Dynamic OCT measurement of corneal deformation by an air puff in normal and cross-linked corneas[J]. Biomed Opt Express，2012，3：473-487.
[21]	Leung CK， Ye C， Weinreb RN. An ultra-high-speed Scheimpflug camera for evaluation of corneal deformation response and its impact on IOP measurement[J]. Invest Ophthalmol Vis Sci，2013，54：2885-2892.