Agreement in central corneal thickness measurement between Corvis ST and ocular response analyzer

Purpose: To investigate the impact of diabetes mellitus–induced changes on intraocular pressure measurements using Goldmann applanation tonometry, Ocular Response Analyzer, and Corvis ST. Methods: Measurements were done using Goldmann applanation tonometry, Ocular Response Analyzer, and Corvis ST in 69 diabetic patients. Biomechanical-corrected intraocular pressure values by Ocular Response Analyzer (IOPcc) and Corvis ST (bIOP) were used. In addition, biometry and tomography were performed and information on diabetes mellitus specific factors was collected. Results were compared to an age-matched group of 68 healthy subjects. Results: In diabetes mellitus, Goldmann applanation tonometry intraocular pressure (P = 0.193) and central corneal thickness (P = 0.184) were slightly increased. Also, IOPcc (P = 0.075) and bIOP (P = 0.542) showed no significant group difference. In both groups, IOPcc was higher than Goldmann applanation tonometry intraocular pressure (P = 0.002, P < 0.001), while bIOP was nearly equal to Goldmann applanation tonometry intraocular pressure (P = 0.795, P = 0.323). Central corneal thickness showed a tendency to higher values in poorly controlled than in controlled diabetes mellitus (P = 0.059). Goldmann applanation tonometry intraocular pressure correlated to central corneal thickness, while IOPcc and bIOP were independent from central corneal thickness in both groups. All intraocular pressure values showed significant associations to corneal biomechanical parameters. Only in diabetes mellitus, bIOP was correlated to Pachy slope (P = 0.023). Conclusion: In diabetes mellitus, Goldmann applanation tonometry intraocular pressure was slightly, but not significantly, increased, which might be caused by a higher central corneal thickness and changes in corneal biomechanical properties. However, intraocular pressure values measured by Ocular Response Analyzer and Corvis ST were not significantly different between diabetes mellitus patients and healthy subjects. The bIOP showed a higher agreement with Goldmann applanation tonometry than IOPcc and was independent from central corneal thickness.

Download Full-text

Central corneal thickness measurement by Fourier domain optical coherence tomography, ocular response analyzer and ultrasound pachymetry

Taiwan Journal of Ophthalmology ◽

10.1016/j.tjo.2014.08.001 ◽

2014 ◽

Vol 4 (4) ◽

pp. 163-169 ◽

Cited By ~ 1

Author(s):

Shu-Wen Chang ◽

Po-Fang Su ◽

Andy Y. Lo ◽

Jehn-Yu Huang

Keyword(s):

Optical Coherence Tomography ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Thickness Measurement ◽

Ocular Response Analyzer ◽

Fourier Domain ◽

Optical Coherence ◽

Ultrasound Pachymetry

Download Full-text

Detecting subclinical keratoconus by biomechanical analysis in tomographically regular keratoconus fellow eyes

European Journal of Ophthalmology ◽

10.1177/11206721211063740 ◽

2021 ◽

pp. 112067212110637

Author(s):

Victor A Augustin ◽

Hyeck-Soo Son ◽

Isabella Baur ◽

Ling Zhao ◽

Gerd U Auffarth ◽

...

Keyword(s):

Visual Acuity ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Case Series ◽

Biomechanical Analysis ◽

Corvis St ◽

Corrected Visual Acuity ◽

The Mean ◽

Best Corrected Visual Acuity ◽

Fellow Eyes

Purpose To analyze the tomographically non-affected second eyes of keratoconus patients using the Corvis ST to detect any biomechanical abnormalities or subclinical keratoconus. Methods In this retrospective, single-center, consecutive case series 244 eyes of 122 keratoconus patients were analyzed between November 2020 and February 2021. Fourteen fellow eyes fulfilled the inclusion criteria and showed no clinical or tomographic signs of keratoconus. Main outcome measures included best-corrected visual acuity, tomographic and biomechanical analyses using Scheimpflug imaging: Pentacam and Corvis ST (Oculus, Wetzlar, Germany). Tomographic analyses included anterior and posterior simulated keratometry, K-Max, central corneal thickness, thinnest corneal thickness, Belin/Ambrosio Ectasia Display, and the ABCD grading system. For biomechanical analyses, the corneal biomechanical index (CBI) and tomographic biomechanical index were used. Results The mean best-corrected visual acuity was 0.01 ± 0.10 logMAR. Mean K-Max was 43.79 ± 1.12 D, mean central corneal thickness 529 ± 25 µm, mean thinnest corneal thickness 524 ± 23 µm, and mean Belin/Ambrosio Ectasia Display 1.0 ± 0.32. The mean CBI was 0.30 ± 0.21. Regular CBI values were found in six of 14 patients. The mean tomographic biomechanical index was 0.47 ± 0.22 with regular values observed in only two of 14 patients. No signs of tomographic or biomechanical abnormalities were shown in only one of 14 keratoconus fellow eyes, with regular ABCD, Belin/Ambrosio Ectasia Display, CBI and tomographic biomechanical index values. Conclusions Tomographically normal fellow eyes of keratoconus patients are rare. In these cases, a biomechanical analysis of the cornea may help detect a subclinical keratoconus. The tomographic biomechanical index was the most sensitive index to verify a mild ectasia.

Download Full-text

Central corneal thickness measurement using ultrasonic pachymetry, rotating scheimpflug camera, and scanning-slit topography exclusively in thin non-keratoconic corneas

Journal of Ophthalmic and Vision Research ◽

10.4103/2008-322x.188392 ◽

2016 ◽

Vol 11 (3) ◽

pp. 245 ◽

Cited By ~ 7

Author(s):

Mehrdad Mohammadpour ◽

Kazem Mohammad ◽

Nasser Karimi

Keyword(s):

Central Corneal Thickness ◽

Corneal Thickness ◽

Thickness Measurement ◽

Scheimpflug Camera ◽

Ultrasonic Pachymetry

Download Full-text

Effect of brimonidine on central corneal thickness in normal tension glaucoma patients

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20192501 ◽

2019 ◽

Vol 7 (6) ◽

pp. 2216

Author(s):

Neethu K. V. ◽

Latha N. V. ◽

Praveena K. K.

Keyword(s):

Intraocular Pressure ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Topical Administration ◽

Normal Tension Glaucoma ◽

Thickness Measurement ◽

Applanation Tonometry ◽

Time Period ◽

Field Assessment ◽

History Of

Background: Brimonidine is a potent ocular hypotensive agent widely used in glaucoma treatment. A reduction in central corneal thickness can lead to an underestimation of intraocular pressure by Goldmann applanation tonometry and vice versa. The aim of this study is to determine whether brimonidine has an effect on central corneal thickness.Methods: 30 eyes of patients who attended the Ophthalmology OPD between the time period October 2017 and June 2018 who were newly diagnosed with normal tension glaucoma with no history of any systemic illness or not on any medication were included. Each patient underwent a complete ophthalmic evaluation including fundus examination, visual field assessment, intraocular pressure, central corneal thickness measurement by pachymetry before as well as 1 month and 6 months after starting treatment with 0.2% topical brimonidine twice daily.Results: Administration of brimonidine 0.2% resulted in an increase in central corneal thickness from 525±21 µm before starting brimonidine to 528±21 µm (p<0.05) after 1 month and 535±20 µm (p<0.001) after 6 months. It also resulted in a reduction in intraocular pressure from an initial value of 16±2 mmHg before starting brimonidine to 14±2 mmHg (p<0.05) and 13±2 mmHg (p<0.05), 1month and 6 months after starting treatment, respectively.Conclusions: The data presented in this study show that topical administration of 0.2% brimonidine twice daily results in a significant increase in central corneal thickness in patients with normal tension glaucoma.

Download Full-text

Central Corneal Thickness Measurement After Cataract Surgery

Cornea ◽

10.1097/ico.0000000000001495 ◽

2018 ◽

Vol 37 (4) ◽

pp. e19-e20 ◽

Cited By ~ 4

Author(s):

Maddalena De Bernardo ◽

Nicola Rosa

Keyword(s):

Cataract Surgery ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Thickness Measurement

Download Full-text

Ocular Response Analyzer Measurements in Keratoconus with Normal Central Corneal Thickness Compared with Matched Normal Control Eyes

Journal of Refractive Surgery ◽

10.3928/1081597x-20100415-02 ◽

2010 ◽

Cited By ~ 8

Author(s):

Bruno M. Fontes ◽

Renato Ambrósio ◽

Guillermo Coca Velarde ◽

Walton Nosé

Keyword(s):

Normal Control ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Ocular Response Analyzer

Download Full-text

Relationship between novel intraocular pressure measurement from Corvis ST and central corneal thickness and corneal hysteresis

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-314370 ◽

2019 ◽

Vol 104 (4) ◽

pp. 563-568 ◽

Cited By ~ 2

Author(s):

Masato Matsuura ◽

Hiroshi Murata ◽

Yuri Fujino ◽

Mieko Yanagisawa ◽

Yoshitaka Nakao ◽

...

Keyword(s):

Intraocular Pressure ◽

Central Corneal Thickness ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Biomechanical Properties ◽

Applanation Tonometry ◽

Corneal Hysteresis ◽

Corneal Resistance Factor ◽

Corvis St ◽

The Relationship

AimsCorvis ST (CST) yields biomechanical corrected IOP (bIOP) which is purported to be less dependent on biomechanical properties. In our accompanied paper, it was suggested that the repeatability of bIOP is high. The purpose of the current study was to assess the relationship between intraocular pressure (IOP) measured with CST and central corneal thickness (CCT) and corneal hysteresis (CH), in comparison with IOP measured with Goldmann applanation tonometry (GAT) and the ocular response analyzer (ORA).MethodsA total of 141 eyes from 141 subjects (35 healthy eyes and 106 glaucomatous eyes) underwent IOP measurements with GAT, CST and ORA. The relationships between IOP measurements (ORA-IOPg, ORA-IOPcc, CST-bIOP and GAT IOP) and biomechanical properties (CCT, CH and corneal resistance factor (CRF)) were analysed using the linear regression analysis.ResultsIOPg, IOPcc and GAT IOP were significantly associated with CCT (p<0.001), whereas bIOP was not significantly associated with CCT (p=0.19). IOPg, bIOP and GAT IOP were significantly associated with CH (IOPg: p<0.001; bIOP: p<0.001; GAT IOP: p=0.0054), whereas IOPcc was not significantly associated with CH (p=0.18). All of IOP records were associated with CRF (p<0.001).ConclusionThe bIOP measurement from CST is independent from CCT, but dependent on CH and CRF.

Download Full-text

Intraocular Pressure Measurement Using Ocular Response Analyzer, Dynamic Contour Tonometer, and Scheimpflug Analyzer Corvis ST

Journal of Ophthalmology ◽

10.1155/2019/3879651 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Lisa Ramm ◽

Robert Herber ◽

Eberhard Spoerl ◽

Frederik Raiskup ◽

Lutz E. Pillunat ◽

...

Keyword(s):

Intraocular Pressure ◽

Healthy Subjects ◽

Corneal Thickness ◽

Applanation Tonometry ◽

Ocular Response Analyzer ◽

Corvis St ◽

Dynamic Contour Tonometer ◽

Iop Measurement ◽

Good Agreement

Purpose. To compare intraocular pressure (IOP) measurements with Goldmann applanation tonometry (GAT), ocular response analyzer (ORA), dynamic contour tonometer (DCT), and Corvis ST (CST) in healthy subjects. Methods. In a prospective, observational study, IOP measurements with GAT (GAT-IOPc), ORA (IOPcc), DCT (DCT-IOP), and CST (bIOP) were performed and analyzed in 94 healthy subjects. Results. Mean age of the participants was 45.6 ± 17.2 years (range 18 to 81 years). Mean GAT-IOPc was 12.9 ± 2.4 mmHg, mean DCT-IOP was 16.1 ± 2.6 mmHg, and mean IOPcc was 15.6 ± 3.3 mmHg. DCT-IOP and IOPcc were significantly higher than GAT-IOPc (P<0.001). Mean bIOP was 13.5 ± 2.4 mmHg that was slightly higher but not significantly different from GAT-IOPc (P=0.146). Correlation analysis of IOP values and central corneal thickness (CCT) revealed a negative correlation between GAT-IOPc and CCT (r = −0.347; P=0.001). However, IOPcc, DCT-IOP, and bIOP showed no significant correlation to CCT. Only bIOP revealed a weak but significant age dependency (r = 0.321, P=0.002). Conclusion. All tonometry devices showed a good agreement of biomechanical corrected IOP values with GAT-IOPc. As no influence of CCT on IOPcc, DCT-IOP, and bIOP was detectable, the used correction algorithms appear to be appropriate in these tonometers in the clinical setting. The highest agreement was found between GAT-IOPc and bIOP. However, bIOP weakly correlated with participants’ age. Further studies are needed to elucidate the role of bIOP for IOP measurement.

Download Full-text