Management of Glaucoma Following Intraocular Procedures

Glaucoma ◽  
2012 ◽  
Author(s):  
Raghu C. Mudumbai
Keyword(s):  
Refractive Surgery ◽  
Structural Integrity ◽  
Corneal Thickness ◽  
Topical Steroid ◽  
Applanation Tonometry ◽  
Dynamic Contour Tonometry ◽  
Glaucomatous Optic Neuropathy ◽  
Clinical Appearance ◽  
Clinical Procedures ◽  
Pressure Spike

The development of glaucoma can occur postoperatively from corneal/refractive, cataract, and vitreoretinal surgery. Additionally, glaucoma may be noted after clinical procedures have been performed, including injections and laser procedures. This chapter is organized into two basic sections: postoperative and post-procedure glaucoma. Background: Currently little is known about the effect of refractive surgery in glaucoma patients or about patients who undergo refractive procedures and may go on to develop glaucoma. •IOP measurement •Measurement of IOP after refractive surgery can be challenging. Corneal properties that are altered after refractive surgery include corneal thickness, corneal curvature, the structural integrity (stiffness or hysteresis), as well as the overlying tear film that interacts with instruments that measure IOP. Photorefractive keratectomy (PRK) additionally ablates portions of Bowman’s layer, which may change corneal resistance. Nomograms have been developed to adjust for IOP change after corneal alteration but usually take only corneak thickness into account, which has led to little success in their use. •Goldmann applanation tonometry (GAT) assumes corneal thickness = 520 microns. Thicker corneas will overestimate IOP and thinner corneas, which result from refractive procedures such as PRK and LASIK, will underestimate IOP. Therefore, GAT may have limited value in measuring true IOP following refractive surgery. Other tonometric devices, like Pascal dynamic contour tonometry, pneumatonometry, and the Reichert ocular response analyzer, may be more accurate. There does not appear to be any simple conversion table that can be referenced in correcting measured IOP after the cornea is altered surgically. Preoperative IOP is probably the most important variable that should be recorded. •The intraoperative pressure spike associated with LASIK may occur in select patients, leading to the development of glaucomatous optic neuropathy. • Pressure-induced stromal keratitis (PISK) is a condition related to steroid-induced elevated IOP that may occur after LASIK. The clinical appearance is similar to diffuse lamellar keratitis (DLK), where there is a diffuse interlamellar haze covering the flap. DLK is an inflamatory response where IOP is not elevated and requires topical steroid treatment for resolution.

Significance of dynamic contour tonometry in evaluation of progression of glaucoma in patients with a history of laser refractive surgery

2019 ◽  
Vol 104 (2) ◽  
pp. 276-281 ◽  
Author(s):  
Sang Yeop Lee ◽  
Eun Woo Kim ◽  
Wungrak Choi ◽  
Chan Keum Park ◽  
Sangah Kim ◽  
...  
Keyword(s):  
Refractive Surgery ◽  
Open Angle Glaucoma ◽  
Corneal Thickness ◽  
Significant Risk ◽  
Applanation Tonometry ◽  
Dynamic Contour Tonometry ◽  
Significant Difference ◽  
History Of ◽  
The Mean ◽  
Laser Refractive Surgery

AimsIn this study, we tested the hypothesis that intraocular pressure (IOP) parameters measured by dynamic contour tonometry (DCT) would be more relevant in progression of glaucoma when there is a history of laser refractive surgery (LRS) than the IOP parameters measured by Goldmann applanation tonometry (GAT) or calculated by correction formulae.MethodsNinety-eight eyes in 54 patients with open-angle glaucoma and a history of LRS were included in this retrospective study. IOP was measured by both GAT and DCT during follow-up. Baseline, mean, and peak IOP, IOP fluctuation, and IOP reduction were measured by each tonometry method. Corrected IOP parameters using central corneal thickness and mean keratometry values were also analysed. Clustered logistic regression was used to identify variables correlated with progression of glaucoma. Areas under the curve (AUCs) for correlated variables were also compared.ResultsThe mean DCT value (OR 1.36, p=0.024), peak DCT value (OR 1.19, p=0.02) and pattern SD (OR 1.10, p=0.016) were significant risk factors for progression. There was a significant difference in the predictive ability of the mean DCT and GAT values (AUC 0.63 and 0.514, respectively; p=0.01) and of the peak DCT and GAT values (0.646 and 0.503, respectively, p=0.009). The AUCs for corrected IOP did not exceed those of DCT.ConclusionsIOP measurements were more associated with progression of glaucoma when measurements were obtained by DCT than by GAT or correction formulae in eyes with a history of LRS.

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

Vision ◽  
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.

scholarly journals Differences between Goldmann Applanation Tonometry and Dynamic Contour Tonometry following Trabeculectomy

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Efstathios T. Detorakis ◽  
Emilia Grammenandi ◽  
Ioannis G. Pallikaris ◽  
Miltiadis K. Tsilimbaris
Keyword(s):  
Mechanical Properties ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Applanation Tonometry ◽  
Goldmann Applanation Tonometry ◽  
Dynamic Contour Tonometry ◽  
Control Group ◽  
Clinical Parameters ◽  
History Of ◽  
The Difference

Background. To evaluate differences between Goldmann Applanation Tonometry (GAT) and Dynamic Controur Tonometry (DCT) following trabeculectomy.Methods. Thirty eight glaucomatous eyes with a history of trabeculectomy (Trabeculectomy group, TG), 20 eyes without a history of trabeculectomy but with a history of latanoprost use (Latanoprost group, LG), and 19 nonglaucomatous eyes (Control group, CG) were included. GAT-IOP, DCT-IOP, the difference between them (dIOP), the central corneal thickness (CCT), the axial length (AL), and the depth of the anterior chamber (ACD) were measured.Results. dIOP was significantly higher in TG (5.19 mmHg) than in LG (4.01 mmHg) and CG (1.98 mmHg). Correlations between AL and dIOP were statistically significant in both TG and LG but not in CG whereas correlations between dIOP and other clinical parameters examined were statistically not significant in all groups.Conclusions. The significantly higher dIOP in TG implies that the bio-mechanical properties of the ocular walls are altered following trabeculectomy.

Sign in / Sign up

Export Citation Format

Share Document