PURPOSE: To evaluate corneal biomechanical properties across the glaucoma spectrum and study the relationship between these measurements and intraocular pressure measured by Goldmann applanation tonometry (GAT-IOP) and central corneal thickness (CCT). DESIGN: Prospective cross-sectional study. SETTING: Tertiary-care teaching institute. STUDY POPULATION: A total of 323 eyes of 323 participants (71 normal, 101 glaucoma suspect [GS], 38 ocular hypertension [OHT], 59 primary angle-closure disease [PACD], 36 primary open-angle glaucoma [POAG], and 18 normal-tension glaucoma [NTG]) who had received no ophthalmic treatment. OBSERVATION PROCEDURES: Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) measured by the Ocular Response Analyzer (ORA). GAT-IOP and CCT recorded in all subjects. MAIN OUTCOME MEASURES: Regression analysis used to determine the relationship between GAT-IOP, CCT, age, CRF, and CH. Bland-Altman plots used to assess agreement between IOP measured by GAT and the ORA (IOPg). RESULTS: CH measurements were significantly less in POAG and NTG compared to normal subjects (P = .034 and P = .030 respectively), regardless of the IOP. The CRF was significantly less in NTG and maximum in POAG and OHT. Regression analysis with CH as dependant variable showed significant association with GAT-IOP and CRF (P < .001) but not CCT, persisting on multivariate analysis (adjusted R(2) = 0.483). GAT-IOP correlated strongly with Goldmann-correlated IOP on the ORA (IOPg) (r = 0.82; P < .001), but limits of agreement between the measurements were poor. CONCLUSIONS: CH and CRF may constitute a pressure-independent risk factor for glaucoma. CRF appears to influence GAT-IOP measurements more than simple geometric thickness measured by CCT. However, IOP measurements from the ORA are not interchangeable with, and are unlikely to replace, Goldmann applanation tonometry at the present time.
PURPOSE: To evaluate corneal biomechanical properties across the glaucoma spectrum and study the relationship between these measurements and intraocular pressure measured by Goldmann applanation tonometry (GAT-IOP) and central corneal thickness (CCT). DESIGN: Prospective cross-sectional study. SETTING: Tertiary-care teaching institute. STUDY POPULATION: A total of 323 eyes of 323 participants (71 normal, 101 glaucoma suspect [GS], 38 ocular hypertension [OHT], 59 primary angle-closure disease [PACD], 36 primary open-angle glaucoma [POAG], and 18 normal-tension glaucoma [NTG]) who had received no ophthalmic treatment. OBSERVATION PROCEDURES: Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) measured by the Ocular Response Analyzer (ORA). GAT-IOP and CCT recorded in all subjects. MAIN OUTCOME MEASURES: Regression analysis used to determine the relationship between GAT-IOP, CCT, age, CRF, and CH. Bland-Altman plots used to assess agreement between IOP measured by GAT and the ORA (IOPg). RESULTS: CH measurements were significantly less in POAG and NTG compared to normal subjects (P = .034 and P = .030 respectively), regardless of the IOP. The CRF was significantly less in NTG and maximum in POAG and OHT. Regression analysis with CH as dependant variable showed significant association with GAT-IOP and CRF (P < .001) but not CCT, persisting on multivariate analysis (adjusted R(2) = 0.483). GAT-IOP correlated strongly with Goldmann-correlated IOP on the ORA (IOPg) (r = 0.82; P < .001), but limits of agreement between the measurements were poor. CONCLUSIONS: CH and CRF may constitute a pressure-independent risk factor for glaucoma. CRF appears to influence GAT-IOP measurements more than simple geometric thickness measured by CCT. However, IOP measurements from the ORA are not interchangeable with, and are unlikely to replace, Goldmann applanation tonometry at the present time.
Authors: Megan Ulmer; Jun Li; Brian L Yaspan; Ayse Bilge Ozel; Julia E Richards; Sayoko E Moroi; Felicia Hawthorne; Donald L Budenz; David S Friedman; Douglas Gaasterland; Jonathan Haines; Jae H Kang; Richard Lee; Paul Lichter; Yutao Liu; Louis R Pasquale; Margaret Pericak-Vance; Anthony Realini; Joel S Schuman; Kuldev Singh; Douglas Vollrath; Robert Weinreb; Gadi Wollstein; Donald J Zack; Kang Zhang; Terri Young; R Rand Allingham; Janey L Wiggs; Allison Ashley-Koch; Michael A Hauser Journal: Invest Ophthalmol Vis Sci Date: 2012-07-03 Impact factor: 4.799
Authors: Carolina N Susanna; Alberto Diniz-Filho; Fábio B Daga; Bianca N Susanna; Feilin Zhu; Nara G Ogata; Felipe A Medeiros Journal: Am J Ophthalmol Date: 2018-01-02 Impact factor: 5.258
Authors: Thao N Yeh; Harry M Green; Yixiu Zhou; Julie Pitts; Britney Kitamata-Wong; Sophia Lee; Shiyin L Wang; Meng C Lin Journal: Invest Ophthalmol Vis Sci Date: 2013-06-06 Impact factor: 4.799
Authors: Ahmed Abdel Karim El Massry; Amr Ahmed Said; Ihab Mohamed Osman; Amr Saad Bessa; Mohammed Ahmed Elmasry; Eman Nabil Elsayed; Nader Hussein Lotfy Bayoumi Journal: Int Ophthalmol Date: 2020-01-08 Impact factor: 2.031