Comparability of three intraocular pressure measurement: iCare pro rebound, non-contact and Goldmann applanation tonometry in different IOP group

Abstract Background Measurement of intraocular pressure (IOP) is essential for glaucoma patients. Many factors such as central corneal thickness (CCT) can affect the accuracy of IOP measurement. The purpose of this study was to evaluate the agreement of IOP measured by non-contact tonometer (NCT), iCare pro rebound tonometer (iCare), and Goldmann applanation tonometer (GAT) in different IOP group. Methods This was a Hospital-based cross-sectional study. Two hundred subjects were enrolled in this study. All subjects underwent IOP measurement using an NCT–iCare–GAT sequence. Bland-Altman, Pearson correlation and intraclass correlation analysis were performed using SPSS 17.0 software. The influence of CCT on each IOP measurement methods was evaluated by linear regression analysis. Results The mean difference (Δ) of NCT–GAT did not differ from (Δ) iCare–GAT in IOP < 10 and 10–21 mmHg group. However, (Δ) NCT–GAT was significantly higher than (Δ) iCare–GAT in IOP 22–30 and > 30 mmHg group (P < 0.05). Bland–Altman analysis showed significant agreement between the three devices (P < 0.01). IOP measurements of the three methods were significantly correlated with CCT (P < 0.01). Conclusions ICare pro shows a higher agreement with GAT over a wide range of IOP compared with NCT. The consistency between the three tonometers was similar in a low and normal IOP range. However, NCT shows a greater overestimate of IOP in moderate and higher IOP group. The variability of IOP measurement affected by CCT is NCT > iCare pro > GAT.

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Usefulness of the Non-Contact Tonometry in Out-Patient Screening

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v15i2.232 ◽

2016 ◽

Vol 15 (2) ◽

Author(s):

Satheesh Solomon T Selvin ◽

Chris Elsa Samson Jacob ◽

Thomas Kuriakose

Keyword(s):

Central Corneal Thickness ◽

Care Center ◽

Corneal Thickness ◽

Tertiary Care ◽

Cross Sectional Study ◽

Applanation Tonometry ◽

Cross Sectional ◽

Significant Difference ◽

Iop Measurement ◽

The Mean

Purpose: Goldmann applanation tonometry (GAT) is considered the gold standard for Intraocular Pressure (IOP) measurement. It has the disadvantages of being a contact device, need for a slit-lamp, non-portability and need of a skilled examiner. Many hospitals are using a Non Contact Tonometry (NCT) as a screening device to save clinician time, however the usefulness is not proved in terms of reliability. This study was aimed to determine the usefulness of the Air-puff tonometer (TONOREF NIDEK II, NIDEK CO., LTD., JAPAN) over a GAT in a tertiary care center. Design: Cross-sectional Study Methods: This was a cross-sectional, non interventional observational study conducted on 224 eyes (right eye) from 224 patients. All patients underwent the IOP measurement with both methods and a central corneal thickness (CCT) measured. The data was analyzed using SPSS 20.0 software. Results: The mean age of the patients was 40.3±11.29 years. There was a statistically significant difference (p<0.001) between the mean NCT and GAT readings which persisted even after correction for central corneal thickness. The correlation between NCT and GAT using Pearson’s correlation coefficient was strong irrespective of the corrections for their corneal thickness (r = 0.751 and 0.718 for uncorrected and corrected values respectively). The correlation of the individual clinicians for the readings varied from moderate to strong. The ROC curve showed the best sensitivity and specificity to occur at around 13 to 14 mmHg. Conclusion: NCT seems to overestimate the IOP at low ranges as compared to the GAT and underestimate at higher ranges. The crossover of the values is seen between 12 to 13 mmHg. The clinician should do an individualized analysis of his/her GAT measurements to the readings of the NCT machine at the clinic to obtain clinician specific nomogram.

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Structural and Biomechanical Corneal Differences between Type 2 Diabetic and Nondiabetic Patients

Journal of Ophthalmology ◽

10.1155/2019/3764878 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

João N. Beato ◽

João Esteves-Leandro ◽

David Reis ◽

Manuel Falcão ◽

Vítor Rosas ◽

...

Keyword(s):

Linear Regression ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Biomechanical Properties ◽

Cross Sectional Study ◽

Applanation Tonometry ◽

Multivariate Linear Regression ◽

Multivariate Linear Regression Analysis ◽

Cross Sectional

Purpose. To analyze and compare corneal structural and biomechanical properties, characterized by corneal hysteresis (CH) and resistance factor (CRF), between patients with and without type 2 diabetes mellitus (DM), and determine the main ocular variables that influence them. Methods. Sixty diabetic and 48 age- and sex-matched non-DM patients were enrolled in this cross-sectional study. The DM group was analyzed according to DM duration (<or ≥ 10 years), HbA1c levels (<or ≥ 7%), and presence of retinopathy. CH and CRF were evaluated using the Ocular Response Analyzer® (ORA). Central corneal thickness (CCT) was determined by Scheimpflug tomography (Pentacam® HR). Intraocular pressure was obtained with ORA (IOPcc) and Goldmann applanation tonometry (IOP-GAT). Univariate and multivariate linear regression analyses were performed to evaluate the relationship between demographical, clinical, and ocular variables with the biomechanical properties. Results. There were no statistically significant differences in the CH and the CRF between DM and non-DM groups (p=0.637 and p=0.439, respectively). Also, there was no statistical difference between groups for the CCT, IOPcc, or IOP-GAT. Multivariate linear regression analysis showed that CH was positively associated with CCT (p<0.001) and negatively associated with IOPcc (p<0.001), while CRF was positively associated with CCT (p<0.001) and IOPcc (p=0.014). Conclusion. The CCT and IOPcc were found to be the main parameters that affect corneal biomechanical properties both in diabetics and controls. In this study, there was no significant effect of DM type 2 on corneal biomechanics.

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Ocular Response Analyzer versus Goldmann Applanation Tonometer for Measurement of Intra-Ocular Pressure

QJM ◽

10.1093/qjmed/hcab109.031 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Rim Raafat Fayez ◽

Mohamed Adel Abdelshafik ◽

Ahmed Ibrahim Aboulenain ◽

Momen Mahmoud Hamdi

Keyword(s):

Corneal Thickness ◽

Cross Sectional Study ◽

Applanation Tonometry ◽

Ocular Response Analyzer ◽

Cross Sectional ◽

Goldmann Applanation Tonometer ◽

Applanation Tonometer ◽

Iop Measurement ◽

The Mean ◽

Method Of Evaluation

Abstract Background Goldmann applanation tonometry (GAT) has been the gold standard for intraocular pressure(IOP) measurement ,since its appearance in clinical practice around 50 years ago.(1) In spite of being almost unchallenged, the last few years have become a sustained search for a new standard method for IOP measurement,. One such recently marketed instrument is the Ocular Response Analyzer (ORA), which able to detect the corneal biomechanics. Aim of the Work is to compare the IOP measurement estimated by Goldmann applanation tonometer to that of ORA and detect the effect of state of refraction, corneal topography and central corneal thickness (CCT) on these measurements. Patients and Methods This cross-sectional study was done from March 2018 to October 2018 on 65 eyes of patients visiting the outpatient clinic. Results The mean GAT IOP was 15.938 ± 6.041 while the mean ORA (IOPcc) and (IOPg) were 19.711 ± 7.59 and 17.242 ± 7.35 mm Hg respectively. There is a strong positive relationship between GAT IOP & ORA IOPg measurement (r = 0.880 – p = <0.001*). Also finding a weak yet significant correlation between IOPg and CCT (r = 0.385, p = 0.001). None of the pressure measurements was affected by refraction or corneal curvature significantly. Conclusion In conclusion, our results suggest that mean IOPs obtained by ORA were significantly higher than that of GAT with different influencing factors that are not completely understood. caution has to be sought when using the ORA, the values obtained ought not to be used interchangeably with the values obtained by 1 GAT, despite the presence of a positive correlation between these values. This underlines the importance of using one and only method of evaluation of the IOP for every patient in successive follow-up visits.

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Comparison of intraocular pressure and central corneal thickness in non-glaucomatous North- East Indian tribals versus general Indians

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v16i3.385 ◽

2019 ◽

Vol 16 (3) ◽

pp. 144-152

Author(s):

Tanie Natung ◽

Prasanta Kumar Goswami ◽

Avonuo Keditsu ◽

Wakaru Shullai

Keyword(s):

Intraocular Pressure ◽

Central Corneal Thickness ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Cross Sectional Study ◽

Cross Sectional ◽

East Indian ◽

North East ◽

The Mean ◽

The Difference

Purpose: To compare the intraocular pressure (IOP) and central corneal thickness (CCT) of non-glaucomatous North-East (NE) Indian tribals and general Indians. Materials and methods: In a prospective, cross-sectional study, the IOP and CCT of non-glaucomatous NE Indian tribals (n = 50) and non-glaucomatous general Indians (n = 50) were compared. Glaucoma was ruled out by history, detailed ocular examinations, and investigations. Results: There was very good correlation between the CCT and IOP values of right and left eyes (p = 0.940 and 0.847, respectively). The difference in the IOP values in the two groups was not statistically significant (p = 0.312 for Oculus Dexter [OD], p = 0.400 for Oculus Sinister [OS]). Similarly, the difference in the CCT values in the two groups was not statistically significant (p = 0.736 for OD and 0.613 for OS). The mean CCT and IOP OD for the whole population was 530.50 ± 35.42 μm and 13.80 ± 2.760 mmHg, respectively. By linear regression analysis, the IOP OD of the whole population had good correlation with CCT OD of the whole population (adjusted r2 = 0.084, p = 0.002), but not with age (adjusted r2=0.000, p=0.314) and sex (adjusted r2 = 0.010, p = 0.163). Similarly, CCT OD for the whole population did not have good correlation with age (adjusted r2 = -0.009, p = 0.762) and sex (adjusted r2 = -0.007, p = 0.603). Conclusions: In this study of individuals with normal corneas and without glaucoma, no racial variation was found in the CCT and IOP values of the two groups. The IOP OD of whole population had good correlation with CCT, but not with age and sex. There was good correlation between OD and OS values of IOP and CCT.

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Study of corneal biomechanical properties in patients with childhood glaucoma

International Journal of Ophthalmology ◽

10.18240/ijo.2020.12.12 ◽

2020 ◽

Vol 13 (12) ◽

pp. 1922-1927

Author(s):

Sara Garcia Caride ◽

Federico Sáenz Francés ◽

Julián García Feijoo

Keyword(s):

Pearson Correlation ◽

Corneal Thickness ◽

Intraclass Correlation ◽

Clinical History ◽

Biomechanical Properties ◽

Cross Sectional Study ◽

Control Group ◽

Ophthalmological Examination ◽

Cross Sectional ◽

Corneal Biomechanical Properties

AIM: To study of corneal biomechanical properties and intraocular pressure (IOP) measured with Corvis Scheimpflug Technology (ST) in patients with childhood glaucoma (CG). METHODS: Cross-sectional study in which 89 eyes were included 56 of them with CG. Only one eye per patient was included. The following variables were obtained from the clinical history and the ophthalmological examination: age, sex, IOP, number of surgeries, and the cup/disc ratio (CDR). The following parameters were recorded using Corvis ST: corrected by biomechanics IOP (bIOP), not corrected IOP (nctIOP), central corneal thickness (CCT), maximum concavity [radius, peak distance (PD) and deformation amplitude], applanation 1 and 2 (length and velocity). The mean age was 23±14.55 and 33±19.5 years old for the control group and CG group, respectively. Totally 36 were males and 53 were females. In the CG group, 7 patients were controlled only with medical treatment. Sixteen had at least one previous goniotomy, 19 had at least one trabeculectomy, and 11 had an Ahmed implant. RESULTS: A significant and positive intraclass correlation coefficient was found between Goldman IOP and the IOP measured by Corvis in both groups. No differences were found between the IOP measured with Corvis and Goldman using a student t-test. Regarding biomechanical parameters, there were differences in the applanation length 2 (A-L2), in the applanation velocity 2 (A-V2) and in the PD. By sex, only the applanation length 1 (A-L1) was found to be different in control group. A positive and significant Pearson correlation was found between CDR and the A-L1. CONCLUSION: Corneal biomechanical properties have shown differences between CG and healthy subjects and also between men and women.

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A Quantitative Comparison of Multispectral Refraction Topography and Autorefractometer in Young Adults

Frontiers in Medicine ◽

10.3389/fmed.2021.715640 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yunru Liao ◽

Zhenlan Yang ◽

Zijing Li ◽

Rui Zeng ◽

Jing Wang ◽

...

Keyword(s):

Correlation Coefficient ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Cross Sectional Study ◽

Cross Sectional ◽

High Agreement ◽

Intraclass Correlation Coefficients ◽

Repeatability And Reproducibility ◽

The Mean

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.

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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.

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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.

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The Effect of Corneal Thickness, Densitometry and Curvature on Intraocular Pressure Measurements Obtained by Applanation, Rebound and Dynamic Contour Tonometry

Vision ◽

10.3390/vision4040045 ◽

2020 ◽

Vol 4 (4) ◽

pp. 45

Author(s):

Marco Antonio de Castro Olyntho Junior ◽

Lucas Bertazzi Augusto ◽

Carolina P. B. Gracitelli ◽

Andrew J. Tatham

Keyword(s):

Intraocular Pressure ◽

Prospective Study ◽

Corneal Thickness ◽

Applanation Tonometry ◽

Corneal Astigmatism ◽

Dynamic Contour Tonometry ◽

Pressure Measurements ◽

Cross Sectional ◽

Corneal Densitometry ◽

The Relationship

Evaluate the effect of corneal thickness, densitometry and curvature on intraocular pressure (IOP) measurements obtained by Goldmann applanation tonometry (GAT), non-contact tonometry (NCT), rebound tonometry (RT), and dynamic contour tonometry (DCT). A cross-sectional prospective study involving 40 participants was performed. Corneal measurements were obtained using Pentacam (Oculus GMbH, Wetzlar, Germany), densitometry was measured at annuli of 0–2, 2–6, 6–10 and 10–12 mm. The relationship between corneal thickness (central, 4 and 6 mm), corneal astigmatism and corneal densitometry and IOP was examined. There was a significant relationship between corneal thickness (central, 4 and 6 mm) and GAT180, GAT90, RT, and NCT (P < 0.001 for all comparisons) but not for DCT. Higher corneal densitometry (6–10 mm and 10–12 mm zones) was associated with higher IOP from GAT180 and GAT90, and higher densitometry in the 6–10 mm zone correlated with higher IOP from NCT, however corneal densitometry increased with age. Accounting for age, the relationship between corneal densitometry and IOP measurements was not significant. In eyes with greater corneal astigmatism there was a greater difference between GAT90 and GAT180 measurements. IOP measurements may be affected by corneal thickness, densitometry and curvature. DCT was less affected by properties of the cornea compared to other devices.

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The relationship between frequency of carbohydrates intake and dental caries: a cross-sectional study in Italian teenagers

Public Health Nutrition ◽

10.1079/phn2001319 ◽

2002 ◽

Vol 5 (4) ◽

pp. 553-560 ◽

Cited By ~ 13

Author(s):

Davide Arcella ◽

Livia Ottolenghi ◽

Antonella Polimeni ◽

Catherine Leclercq

Keyword(s):

Dental Caries ◽

Starch Content ◽

Pearson Correlation ◽

Linear Regression Analysis ◽

Real Life ◽

Cross Sectional Study ◽

Multiple Regression Model ◽

Stepwise Multiple Regression ◽

Cross Sectional ◽

The Relationship

AbstractObjective:To propose an approach for investigation of the relationship between the frequency of carbohydrates intake and dental caries in real-life conditions.Design:The frequency of separate eating events (with the exclusion of lunch and dinner) and their sugars and starch content were assessed on the basis of diaries collected for seven consecutive days. The total number of decayed, missing and filled teeth (DMFT) was assessed through clinical examination. The interrelation between DMFT and frequency of eating events was analysed through Pearson correlation coefficient and stepwise forward linear regression analysis.Setting:Italy.Subjects:One hundred and ninety-three students (males and females, mean age 16 years) of a secondary school.Results:Individual DMFT varied between 0 (24% of subjects) and 12, with a mean of 3. Once lunch and dinner were excluded, the mean number of separate eating events was 2.9. A statistically significant relationship was found between DMFT and eating frequency thus defined. Correlations were calculated considering only eating events containing a proportion of sugars or starch higher than different cut-off levels. In a stepwise multiple regression model for DMFT, the frequency of ‘high sugars and high starch events’ accounted for 8% of the DMFT variance. Overall frequency of separate eating events defined according to their content of both sugars and starch accounted for 18% of the DMFT variance. A stronger correlation was found among males only.Conclusions:The precise characterisation of eating events in terms of their sugars and starch content allows us to explain a consistent percentage of the variability in DMFT.

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