Tonometry

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 12369 Experts worldwide ranked by ideXlab platform

Robert L Stamper - One of the best experts on this subject based on the ideXlab platform.

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Robert L Stamper
    Abstract:

    PurposeTo determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL®), and to glaucoma stage as assessed by cup-to-disc ratio (CDR).DesignProspective, cross-sectional tricenter observation study.Patients and Method

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    PURPOSE To determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL), and to glaucoma stage as assessed by cup-to-disc ratio (CDR). DESIGN Prospective, cross-sectional tricenter observation study. PATIENTS AND METHODS From three glaucoma specialty practices a sample of 406 independent eyes was included. After ultrasound pachymetry, intraocular pressure was measured using PASCAL and Goldmann applanation Tonometry and cup-to-disc ration was reassessed. Demographic data were included in the multivariate analysis. RESULTS Mean corneal thickness was 540 microm. African Americans and normal-tension glaucoma patients showed the lowest values (518 microm and 522 microm, respectively). These values were significantly thinner than the central corneal thickness of Caucasians (549 microm) and ocular hypertensives (564 microm). Intraocular pressure assessed by Goldmann applanation Tonometry shows a significant correlation with central corneal thickness (r = 0.068, P < 0.001), whereas PASCAL is not significantly associated with central corneal thickness (r < 0.001, P = 0.997). Increased IOP is significantly correlated with large ocular pulse amplitudes (r = 0.13, P < 0.001), which is predominantly seen in ocular hypertensives. A significant negative correlation was detected between cup-to-disc ratio and central corneal thickness (r = 0.102, P < 0.001). CONCLUSION Glaucoma patients with thin central corneal thickness are more likely to be found at an advanced stage of the disease and among those with normal-tension glaucoma and black African ancestry. Underestimation of intraocular pressure by Goldmann applanation Tonometry could be one causative factor.

  • clinical comparison of contour and applanation Tonometry and their relationship to pachymetry
    Archives of Ophthalmology, 2005
    Co-Authors: Christoph Kniestedt, Joyce Choe, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    Objectives To compare intraocular pressure readings of recently introduced dynamic contour Tonometry (DCT) with pneumaTonometry (PTG) and Goldmann applanation Tonometry (GAT) and to correlate central corneal thickness (CCT) with these readings. Design Prospective, cross-sectional observation and instrument validation study. We included 258 independent eyes with normal anterior segment examinations results, irrespective of glaucoma diagnosis or glaucoma suspect. After pachymetry, DCT, PTG, and GAT were performed in a randomized order. Intraocular pressures as measured by DCT, PTG, and GAT were compared with each other and with CCT. Results Eyes with thinner CCTs tended to yield lower intraocular pressure measurements by GAT. A significant correlation (Pearson product moment correlation, P R 2  = 0.060). Variation of CCT had no significant effect on intraocular pressure measurements by PTG ( P  = .10; R 2  = 0.01) and DCT ( P  = .80; R 2 P Conclusions Goldmann applanation Tonometry readings are potentially influenced by CCT, whereas PTG and DCT seem to be less dependent on CCT. Correlation between CCT and GAT is not linear. A simple correction formula suggesting a linear relationship might not be correct.

Christoph Kniestedt - One of the best experts on this subject based on the ideXlab platform.

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Robert L Stamper
    Abstract:

    PurposeTo determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL®), and to glaucoma stage as assessed by cup-to-disc ratio (CDR).DesignProspective, cross-sectional tricenter observation study.Patients and Method

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    PURPOSE To determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL), and to glaucoma stage as assessed by cup-to-disc ratio (CDR). DESIGN Prospective, cross-sectional tricenter observation study. PATIENTS AND METHODS From three glaucoma specialty practices a sample of 406 independent eyes was included. After ultrasound pachymetry, intraocular pressure was measured using PASCAL and Goldmann applanation Tonometry and cup-to-disc ration was reassessed. Demographic data were included in the multivariate analysis. RESULTS Mean corneal thickness was 540 microm. African Americans and normal-tension glaucoma patients showed the lowest values (518 microm and 522 microm, respectively). These values were significantly thinner than the central corneal thickness of Caucasians (549 microm) and ocular hypertensives (564 microm). Intraocular pressure assessed by Goldmann applanation Tonometry shows a significant correlation with central corneal thickness (r = 0.068, P < 0.001), whereas PASCAL is not significantly associated with central corneal thickness (r < 0.001, P = 0.997). Increased IOP is significantly correlated with large ocular pulse amplitudes (r = 0.13, P < 0.001), which is predominantly seen in ocular hypertensives. A significant negative correlation was detected between cup-to-disc ratio and central corneal thickness (r = 0.102, P < 0.001). CONCLUSION Glaucoma patients with thin central corneal thickness are more likely to be found at an advanced stage of the disease and among those with normal-tension glaucoma and black African ancestry. Underestimation of intraocular pressure by Goldmann applanation Tonometry could be one causative factor.

  • clinical comparison of contour and applanation Tonometry and their relationship to pachymetry
    Archives of Ophthalmology, 2005
    Co-Authors: Christoph Kniestedt, Joyce Choe, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    Objectives To compare intraocular pressure readings of recently introduced dynamic contour Tonometry (DCT) with pneumaTonometry (PTG) and Goldmann applanation Tonometry (GAT) and to correlate central corneal thickness (CCT) with these readings. Design Prospective, cross-sectional observation and instrument validation study. We included 258 independent eyes with normal anterior segment examinations results, irrespective of glaucoma diagnosis or glaucoma suspect. After pachymetry, DCT, PTG, and GAT were performed in a randomized order. Intraocular pressures as measured by DCT, PTG, and GAT were compared with each other and with CCT. Results Eyes with thinner CCTs tended to yield lower intraocular pressure measurements by GAT. A significant correlation (Pearson product moment correlation, P R 2  = 0.060). Variation of CCT had no significant effect on intraocular pressure measurements by PTG ( P  = .10; R 2  = 0.01) and DCT ( P  = .80; R 2 P Conclusions Goldmann applanation Tonometry readings are potentially influenced by CCT, whereas PTG and DCT seem to be less dependent on CCT. Correlation between CCT and GAT is not linear. A simple correction formula suggesting a linear relationship might not be correct.

Joyce Choe - One of the best experts on this subject based on the ideXlab platform.

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Robert L Stamper
    Abstract:

    PurposeTo determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL®), and to glaucoma stage as assessed by cup-to-disc ratio (CDR).DesignProspective, cross-sectional tricenter observation study.Patients and Method

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    PURPOSE To determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL), and to glaucoma stage as assessed by cup-to-disc ratio (CDR). DESIGN Prospective, cross-sectional tricenter observation study. PATIENTS AND METHODS From three glaucoma specialty practices a sample of 406 independent eyes was included. After ultrasound pachymetry, intraocular pressure was measured using PASCAL and Goldmann applanation Tonometry and cup-to-disc ration was reassessed. Demographic data were included in the multivariate analysis. RESULTS Mean corneal thickness was 540 microm. African Americans and normal-tension glaucoma patients showed the lowest values (518 microm and 522 microm, respectively). These values were significantly thinner than the central corneal thickness of Caucasians (549 microm) and ocular hypertensives (564 microm). Intraocular pressure assessed by Goldmann applanation Tonometry shows a significant correlation with central corneal thickness (r = 0.068, P < 0.001), whereas PASCAL is not significantly associated with central corneal thickness (r < 0.001, P = 0.997). Increased IOP is significantly correlated with large ocular pulse amplitudes (r = 0.13, P < 0.001), which is predominantly seen in ocular hypertensives. A significant negative correlation was detected between cup-to-disc ratio and central corneal thickness (r = 0.102, P < 0.001). CONCLUSION Glaucoma patients with thin central corneal thickness are more likely to be found at an advanced stage of the disease and among those with normal-tension glaucoma and black African ancestry. Underestimation of intraocular pressure by Goldmann applanation Tonometry could be one causative factor.

  • clinical comparison of contour and applanation Tonometry and their relationship to pachymetry
    Archives of Ophthalmology, 2005
    Co-Authors: Christoph Kniestedt, Joyce Choe, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    Objectives To compare intraocular pressure readings of recently introduced dynamic contour Tonometry (DCT) with pneumaTonometry (PTG) and Goldmann applanation Tonometry (GAT) and to correlate central corneal thickness (CCT) with these readings. Design Prospective, cross-sectional observation and instrument validation study. We included 258 independent eyes with normal anterior segment examinations results, irrespective of glaucoma diagnosis or glaucoma suspect. After pachymetry, DCT, PTG, and GAT were performed in a randomized order. Intraocular pressures as measured by DCT, PTG, and GAT were compared with each other and with CCT. Results Eyes with thinner CCTs tended to yield lower intraocular pressure measurements by GAT. A significant correlation (Pearson product moment correlation, P R 2  = 0.060). Variation of CCT had no significant effect on intraocular pressure measurements by PTG ( P  = .10; R 2  = 0.01) and DCT ( P  = .80; R 2 P Conclusions Goldmann applanation Tonometry readings are potentially influenced by CCT, whereas PTG and DCT seem to be less dependent on CCT. Correlation between CCT and GAT is not linear. A simple correction formula suggesting a linear relationship might not be correct.

Alan Bostrom - One of the best experts on this subject based on the ideXlab platform.

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Robert L Stamper
    Abstract:

    PurposeTo determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL®), and to glaucoma stage as assessed by cup-to-disc ratio (CDR).DesignProspective, cross-sectional tricenter observation study.Patients and Method

  • correlation between intraocular pressure central corneal thickness stage of glaucoma and demographic patient data prospective analysis of biophysical parameters in tertiary glaucoma practice populations
    Journal of Glaucoma, 2006
    Co-Authors: Christoph Kniestedt, Joyce Choe, Jorg Sturmer, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    PURPOSE To determine the correlation of central corneal thickness (CCT) to Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT, PASCAL), and to glaucoma stage as assessed by cup-to-disc ratio (CDR). DESIGN Prospective, cross-sectional tricenter observation study. PATIENTS AND METHODS From three glaucoma specialty practices a sample of 406 independent eyes was included. After ultrasound pachymetry, intraocular pressure was measured using PASCAL and Goldmann applanation Tonometry and cup-to-disc ration was reassessed. Demographic data were included in the multivariate analysis. RESULTS Mean corneal thickness was 540 microm. African Americans and normal-tension glaucoma patients showed the lowest values (518 microm and 522 microm, respectively). These values were significantly thinner than the central corneal thickness of Caucasians (549 microm) and ocular hypertensives (564 microm). Intraocular pressure assessed by Goldmann applanation Tonometry shows a significant correlation with central corneal thickness (r = 0.068, P < 0.001), whereas PASCAL is not significantly associated with central corneal thickness (r < 0.001, P = 0.997). Increased IOP is significantly correlated with large ocular pulse amplitudes (r = 0.13, P < 0.001), which is predominantly seen in ocular hypertensives. A significant negative correlation was detected between cup-to-disc ratio and central corneal thickness (r = 0.102, P < 0.001). CONCLUSION Glaucoma patients with thin central corneal thickness are more likely to be found at an advanced stage of the disease and among those with normal-tension glaucoma and black African ancestry. Underestimation of intraocular pressure by Goldmann applanation Tonometry could be one causative factor.

  • clinical comparison of contour and applanation Tonometry and their relationship to pachymetry
    Archives of Ophthalmology, 2005
    Co-Authors: Christoph Kniestedt, Joyce Choe, Alan Bostrom, Shan Lin, Michelle Nee, Robert L Stamper
    Abstract:

    Objectives To compare intraocular pressure readings of recently introduced dynamic contour Tonometry (DCT) with pneumaTonometry (PTG) and Goldmann applanation Tonometry (GAT) and to correlate central corneal thickness (CCT) with these readings. Design Prospective, cross-sectional observation and instrument validation study. We included 258 independent eyes with normal anterior segment examinations results, irrespective of glaucoma diagnosis or glaucoma suspect. After pachymetry, DCT, PTG, and GAT were performed in a randomized order. Intraocular pressures as measured by DCT, PTG, and GAT were compared with each other and with CCT. Results Eyes with thinner CCTs tended to yield lower intraocular pressure measurements by GAT. A significant correlation (Pearson product moment correlation, P R 2  = 0.060). Variation of CCT had no significant effect on intraocular pressure measurements by PTG ( P  = .10; R 2  = 0.01) and DCT ( P  = .80; R 2 P Conclusions Goldmann applanation Tonometry readings are potentially influenced by CCT, whereas PTG and DCT seem to be less dependent on CCT. Correlation between CCT and GAT is not linear. A simple correction formula suggesting a linear relationship might not be correct.

Gabi Shemesh - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of intraocular pressure measurements using Goldmann tonometer, I-care pro, Tonopen XL, and Schiotz tonometer in patients after Descemet stripping endothelial keratoplasty
    Wolters Kluwer Medknow Publications, 2017
    Co-Authors: Oded Ohana, David Varssano, Gabi Shemesh
    Abstract:

    Purpose: Post-Descemet stripping endothelial keratoplasty (DSEK) patients are prone for intraocular pressure (IOP) elevations and glaucoma. Corneal characteristics influence various IOP measuring devices in various ways. The aim of this study was to evaluate the agreement between four different IOP measuring devices: Goldmann applanation tonometer (GAT), I-care pro, Tonopen XL, and Schiotz tonometr in patients who underwent DSEK. Methods: This was a prospective comparative study using a convenience cohort of post-DSEK patients with compact grafts. Post-DSEK patients had IOP measured using GAT, I-care Pro, Tonopen XL, and Schiotz tonometer. Measurements were compared and agreement assessed. Wilcoxon signed-rank test was used for comparison of means as variables did not show a normal distribution. Bland–Altman plots were used for assessing agreement. Results: Thirty eyes of 24 patients were included in the study. Mean time from DSEK surgery was 25.31 ± 13.05 months. Mean IOP with GAT, I-care pro, Tonopen XL, and Schiotz tonometer was 13.99 ± 3.76, 13.92 ± 3.36, 13.31 ± 3.89, and 12.83 ± 4.07, respectively. GAT, I-care pro, and Tonopen XL had similar mean IOP measurements (P = 0.135 and P = 0.551, respectively), while Schiotz Tonometry measurements were higher (P = 0.046). Bland–Altman plots show good agreement between GAT, Tonopen XL, and I-care pro. GAT and Schiotz Tonometry show less agreement, with large variations in the differences of measured IOP. Conclusions: IOP measurements in post-DSEK patients showed good agreement between GAT and either Tonopen XL or I-care pro. Schiotz tonometer has large variations in this patient group. IOP measurements and IOP difference between devices were not dependent on central corneal thickness

  • intraocular pressure measurements with goldmann applanation Tonometry and dynamic contour Tonometry in eyes after intralasik or lasek
    Clinical Ophthalmology, 2012
    Co-Authors: Gabi Shemesh, Uri Soiberman, Shimon Kurtz
    Abstract:

    Background and methods Myopic photorefractive surgery induces a reduction in central corneal thickness, which may lead to underestimation of intraocular pressure. This retrospective clinical study compared intraocular pressure measurements obtained by Goldmann applanation Tonometry (GAT) and dynamic contour Tonometry (DCT-Pascal) in eyes undergoing myopic intralaser-assisted in situ keratomileusis (IntraLASIK) or laser-assisted subepithelial keratomileusis (LASEK).

  • pressure phosphene Tonometry versus goldmann applanation Tonometry for measuring intraocular pressure before and after lasik
    Journal of Refractive Surgery, 2007
    Co-Authors: Gabi Shemesh, David Varssano, Oran Man, Adi Michaeli, Moshe Lazar
    Abstract:

    PURPOSE To compare pressure phosphene Tonometry with Goldmann applanation Tonometry for measuring intraocular pressure (IOP) before and after LASIK. METHODS Forty-three (18 men and 25 women) consecutive healthy patients underwent complete pre- and postoperative LASIK ophthalmologic assessments including manifest and cycloplegic refraction, keratometry, and central corneal thickness. Three repetitive sets of pressure phosphene Tonometry and Goldmann applanation Tonometry measurements were performed the day before and 3 months following uneventful LASIK. RESULTS Mean preoperative spherical equivalent refraction was -4.70 +/- 2.50 diopters (D) (range: -1.50 to -12.90 D) and mean preoperative keratometry was 43.95 +/- 1.08 D. After LASIK, spherical equivalent refraction was +0.23 +/- 0.11 D and mean keratometry was 39.46 +/- 2.28 D. Preoperative pressure phosphene Tonometry (12.16 +/- 1.58 mmHg) and Goldmann applanation Tonometry (12.01 +/- 1.55 mmHg) IOP measurements were similar. Postoperative IOP was 10.30 +/- 1.16 mmHg with Goldmann applanation Tonometry and 12.20 +/- 1.62 mmHg with pressure phosphene Tonometry. The postoperative IOP difference between Goldmann applanation Tonometry and pressure phosphene Tonometry was 0.15 +/- 1.12 mmHg (P = .41). The mean change in pachymetry after LASIK was 68.73 +/- 73 microm. The change in Goldmann applanation between preoperative and postoperative LASIK values was 1.71 +/- 1.43 mmHg (P < .0001), a change that was strongly correlated with changes in corneal thickness (R = 0.75, P < .0001) and keratometry (R = 0.72, P < .0001). No such correlations were found with pressure phosphene Tonometry. CONCLUSIONS Goldmann applanation Tonometry-measured IOP decrease after LASIK is strongly correlated with a decrease in central corneal thickness and changes in keratometry, whereas pressure phosphene Tonometry-measured IOP is independent of corneal thickness. Pressure phosphene Tonometry appears to be a more reliable method for recording Tonometry in these patients.