Goldmann Applanation Tonometer Research Articles

Agreement of intraocular pressure measurement by scleral Schiotz and Goldmann applanation tonometer

Aim & background : Intraocular pressure (IOP) measured through the sclera has some advantages over IOP measured through cornea. This study aimed to determine the agreement between IOP as estimated by scleral Schiotz (SS) tonometer and Goldmann applanation tonometer (GAT). Methods: In this cross-sectional observational study, IOP was measured by GAT on the cornea and Schiotz tonometer on the temporal sclera. Axial length and central corneal thickness (CCT) were noted. IOP was then estimated from SS IOP as eGAT using a predictive formula. Agreement of IOP corrected for CCT (cGAT) with eGAT and SS IOP were assessed. The effects of age, axial length, refraction, CCT, gender, and ocular and systemic comorbidity on measured IOP were also assessed. Results: The study included 155 patients with a mean age of 54.27 ± 10.02 years. Mean IOP measured by GAT and scleral Schiotz were 16.58 ± 2.76 mm Hg and 16.10 ± 2.96 mm Hg, respectively. The mean IOP by cGAT and eGAT were 16.70 ± 2.80 mm Hg and 17.07 ± 3.10 mm Hg, respectively. Both eGAT & SS IOP had good agreement with cGAT on the Bland-Altmann plot (p = 0.96 & 0.51, respectively). Further, SS IOP showed good agreement even with GAT IOP (p = 0.78). Age, axial length, refraction, central corneal thickness, gender, and ocular and systemic comorbidity did not show significant correlation with IOP measurement. Conclusion: Estimated GAT IOP showed good agreement with measured GAT values. SS IOP also agreed well with GAT IOP. Clinical significance IOP measurement on the sclera using Schiotz can be used as an alternative to GAT.

Agreement and Reliability of Transpalpebral Tonometers with Goldmann Applanation Tonometer—A Systematic Review and Meta-analysis

TopicThe systematic review and meta-analysis consolidates the extant body of evidence comparing reliability and agreement between Transpalpebral Tonometers (TT) and Goldmann Applanation Tonometer (GAT). Clinical RelevanceWith a global prevalence of 3.54 percent, glaucoma stands as the second leading cause of preventable blindness. Projections indicate a rise to 111 million cases by 2040. Existing literature presents inconsistent findings while comparing TT and GAT. The derivation of summary estimates assessing their agreement holds significance given TT’s multifaceted applicability in clinical, community, and home settings. MethodsSystematic review was conducted using PubMed, Cochrane Library, and Google Scholar from January 2000 to December 2022. Two reviewers independently evaluated, enumerated, and extracted studies and data based on eligibility criteria. The Quality Assessment for Diagnostic Accuracy Studies (QUADAS-2) checklist was used to assess study quality. The summary measures were pooled using the random effects model as mean difference (MD), and 95% LoA (Limits of Agreement). We assessed heterogeneity using the I2 statistic. The study protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO - CRD42022321693). ResultsA total of 26 methods comparison studies (3577 eyes) were included in the meta-analysis. The overall random-effects MD (TT – GAT), SD and 95% LoA for IOP were -0.70 ± 4.15 mmHg (-8.83 to 7.43 mmHg). In the subgroup analysis based on index test devices used, Easyton showed the lowest MD, SD (-0.29 ± 2.35 mmHg), and 95% LoA (-4.90 to 4.32 mmHg). In the univariate meta-regression model, we found that, on average, studies examining normal eyes reported a statistically significant lower mean difference of 2.67 mmHg (95% CI: 0.27 to 5.07 mmHg; P = 0.03) between TT and GAT, compared to studies that assessed eyes with mixed ocular condition. ConclusionIn the current meta-analysis, we found a small MD in the measured IOP between the two tonometers. However, given the high heterogeneity and a wider LoA, it is not advisable to use TT interchangeably with GAT.

Agreement between the Icare HOME tonometer and the Goldmann Applanation Tonometry in the assessment of the Peak Intraocular Pressure in the Water-Drinking Test.

To investigate the agreement between the Icare HOME tonometer and the Goldmann Applanation Tonometry (GAT) in assessing the Peak Intraocular Pressure during the Water-Drinking Test (WDT). Prospective cross-sectional study. 79 eyes of 41 open-angle glaucoma patients were included in the study. All of the included patients underwent a training session provided by ophthalmologist specialists to use the Icare® Home tonometer. Then the IOP was first measured with Goldmann applanation tonometry (AT900; Haag-Streit; Köniz, Suiça) by a trained physician, immediately followed by Icare® Home tonometry (TA022, iCare Oy, Vanda, Finland) measurement by the patient. Four measurements were taken with each device with 15 min difference as established by the WDT. The agreement and degree of correlation of the peak IOP by both tonometers were assessed. The agreement between iCare and Goldmann Applanation Tonometer was high during the WDT: the intraclass correlation coefficient (r) between the two methods from basal to 45 min: 0.94 (p < 0.001), at basal: 0.91 (p < 0.001), at 15 min: 0.94 (p < 0.001), at 30 min: 0.94 (p < 0.001), at 45 min: 0.95 (p < 0.001) and for peak IOP: 0.94 (p < 0.001). There was no significant difference between peak IOP with GAT and iCare 18.3 ± 4.6 (10-33) and 18.5 ± 5.0 (0-33) (p = 0.533), nor between the delta of fluctuation between basal and peak IOP with GAT and iCare 3.96 ± 3.22 and 4.54 ± 3.92 (p = 0.054). Our study demonstrated a high agreement between iCare HOME and Goldmann Applanation Tonometer during the WDT in a clinical environment with supervision.

Comparison of Intraocular Pressure Measurement by iCare Tonometer and Goldman Applanation Tonometer

Objective: To compare the Intraocular Pressure measured by the Goldmann Applanation tonometer with by iCare ic100 tonometer in normal human eye to determine the accuracy and reliability of both methods. Study Design: Comparative cross-sectional study. Place and Duration of Study: Ophthalmology Department, Combined Military Hospital, Quetta Pakistan, from Oct 2022 to Apr 2023. Methodology: Approval was secured prior to enrolling every individual, protecting their privacy throughout the process. All instruments adhered to the manufacturer's guidelines for calibration. A single ophthalmologist assessed the intraocular pressure of all participants. In our study we included 400 eyes (200 right and 200 left) among 200 patients. Initially, study eyes were inspected using a slit lamp. Subsequently, iCare tonometer and Goldman applanation tonometer were employed to gauge the intraocular pressure. Results: Out of 200, 87 patients (43.5%) were male and 113(56.5%) were females. Median age of the patients was 51.00(45-58) years range from 22-77 years. Mean IOP measured by iCare was 19.01±7.86 mmHg and by Goldman applanation tonomter was 20.14±8.15 mmHg. The correlation coefficient value between the readings of two instruments was r=0.866 with significant p value (p&lt; 0.001). Conclusion: The iCare ic100 consistently provides high intraocular pressure measurements (2-3mmHg) compared to the Goldmann Applanation tonometer across various sub Groups.

Comparison between Goldmann Applanation Tonometry and Air Puff Tonometry for Measurement of Intraocular Pressure in Siliconized Eyes

Abstract Background Silicone oil (SO) has been a part of vitreoretinal surgery since the 1960s. The use of silicone oil in conjunction with advanced vitreous surgical techniques can successfully treat complicated retinal detachment (RD). Aim of the Work to compare the intraocular pressure (IOP) measurements following Pars Plana Vitrectomy (PPV) with injection of Silicone Oil (SO) by Goldmann applanation tonometry (GAT) and noncontact Air Puff Tonometer (APT). Patients and Methods This study included a total of 165 eyes of 165 patients. Of these 165 patients, 110 have undergone PPV and silicone oil injection, while the remaining 55 participants served as the control group. Results The participants in our study were divided into a control group, and a siliconized group which was subdivided into SO 1000 cSt (Group A) and SO 5000 cSt (Group B). The control group had an average age of 50.65±12.26 years, Group A had an average age of 53.53±12.04 years, and Group B had an average age of 55.45±12.02 years. The control group in our study consisted of 28 males (50.9%) and 27 females (49.1%), while Group A had 37 males (67.3%) and 18 females (32.7%), and Group B had 38 males (69.1%) and 17 females (30.9%). Central corneal thickness (CCT) was measured for all participants. The average CCT was 536.53±28.66µm for the control group, 531.67±29.19µm for Group A, and 527.13±28.79µm for Group B. There was no statistically significant difference in the CCT measurements between the study groups (P = 0.410). The average IOP values were obtained using both the airpuff tonometer (APT) and Goldmann applanation tonometry (GAT) methods. In the control group, the average IOP was 16.56±2.98 mmHg using APT and 15.27±2.73 mmHg using GAT. For Group A, the average IOP was 17.09±7.0 mmHg with APT and 15.61±6.43 mmHg with GAT. In Group B, the average IOP was 16.71±4.93 mmHg using APT and 15.13±4.63 mmHg using GAT. The P-value was &amp;gt;0.05 in all groups, indicating that the differences were not statistically significant. Conclusion the results showed a correspondence between the Goldmann applanation tonometer (GAT) and the airpuff tonometer (APT) in siliconized eyes. The differences in intraocular pressure (IOP) measurements between the two instruments were minimal and not statistically significant, with APT measurements being slightly higher than GAT measurements. The study also concluded that there is a greater chance of increased IOP following pars plana vitrectomy (PPV) and silicone oil (SO) injection with SO 1000 cSt compared to 5000 cSt, but this difference was not statistically significant. Furthermore, this IOP difference between the two methods was not correlated with age, gender, CCT, or lens status of the patients. Thus, there is good agreement between the two methods.

Comparison of Intraocular Pressure Measurement by Air-Puff Tonometer and Goldmann Applanation Tonometer in Correlation to Corneal Pachymetry in Adolescence Age Group in Normal People

Abstract Purpose To assess the most accurate and practical technique for intraocular pressure (IOP) measurement in children and adolescents Type of the Study Cross-sectional observational Methods 90 eyes of 45 patients were included in this study. Central corneal thickness (CCT) was measured using specular microscopy. IOP was assessed by Goldman applanation tonometer (GAT), Non-contact tonometry (Air-puff), and Tono- Pen in both right and left eyes. Results The mean age of participants was 14.8 years. Mean CCT was 548.7 µm in the right eye and 549.2 µm in the left eye (P = 0.687). Mean IOP measured by GAT, Air-puff, and Tono-Pen was 11.7, 14.1, and 11.3 mmHg in the right eye, respectively, and 11.7, 14.2, and 11.5 mmHg in the left eye, respectively. Air-puff readings were significantly higher than GAT and Tono-Pen (P &amp;gt; 0.0001) in both the right and the left eyes. On the other hand, Tono-Pen showed no statistically significant difference from GAT measurements either in the right (P = 0.447) or the left eye (P = 1). The highest correlation with GAT was seen with the Air-puff. CCT was positively correlated with all used devices. Conclusion Tono-Pen provides the most accurate alternative for GAT. Although Air-puff offers a more accessible option for IOP measurement in adolescents, attention should be taken as it gives significantly higher measurements.

Correlation between optical coherence tomography angiography measured vessel density and retinal nerve fiber layer thickness in moderate primary open angle glaucoma cases and normal controls

: Aim of this study was to establish a correlation between findings obtained from Optical Coherence Tomography Angiography (OCT-A) and Retinal Nerve Fiber Layer (RNFL) thickness measurements in a series of moderate Primary Open Angle Glaucoma (POAG) cases and normal controls. In this observational cross-sectional study a total of 100 eyes were included, comprising 50 eyes with glaucoma and 50 control eyes without glaucoma. All participants underwent comprehensive anterior and posterior segment evaluations, intraocular pressure (IOP) measurement using Goldmann applanation tonometer, gonioscopy, visual field testing, and OCT imaging, which included OCT-A. The OCT-A imaging was performed using the RTvue XR Avanti by Optovue. Two types of analysis were conducted: a comparative analysis between the normal and glaucomatous groups using an unpaired t-test to assess differences in RNFL thickness and vessel density values, and a correlation analysis within each group to examine the strength of correlation between RNFL loss and reduction in vascular density. The results showed a significant reduction in vessel density index in all quadrants of glaucomatous eyes compared to normal eyes. Moreover, this reduced vessel density was found to be significantly correlated with the reduction in RNFL thickness in glaucoma patients. Specifically, the uperior and inferior quadrants exhibited the strongest correlation with each other. The severity of vascular compromise demonstrated a significant correlation with the extent of retinal nerve fiber loss in patients with glaucoma. OCT-A can serve as a valuable adjunct in the diagnosis of glaucoma and monitoring its progression.

Prevalence of Normal-Tension Glaucoma in Patients With Primary Aldosteronism

PurposeTo investigate patients with primary aldosteronism (PA) and the prevalence of normal-tension glaucoma (NTG). DesignCross-sectional study. MethodsNewly diagnosed PA patients were evaluated in this cross-sectional study, with ophthalmic examinations such as intraocular pressure (IOP) measurements by a Goldmann applanation tonometer, central corneal thickness (CCT), slit-lamp biomicroscopic examination, gonioscopy, ophthalmoscopy, fundus photography, visual field test with a Humphrey Field Analyzer 24-2 SITA Standard program, and optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer (RNFL), performed in each of the subjects. Optic disc appearance, perimetric results, OCT results, and other ocular findings were all used for determining the glaucoma diagnosis. The primary outcome was shown the prevalence of NTG in patients with PA. ResultsNTG prevalence in the 212 PA patients was 11.8% (95% confidence interval [CI], 4.7%-20.7%). As compared to the hypertensive patients without PA, the hypertensive patients with PA exhibited a significantly increased NTG prevalence (odds ratio; 4.019, 95% CI, 1.223-13.205; P = .022). Increased NTG prevalence was associated with age, ranging from 8.8% (95% CI, 2.1%-15.6%) for those aged 40 to 49 years, to 37.5% (95% CI, 13.8%-61.2%) for those aged 70 years and older. In 72 hypertensive patients without PA, who were used as the controls, NTG prevalence was 5.2%, with a 95% CI ranging from 0.5% to 14.4%. ConclusionsThere was an 11.8% prevalence of NTG in PA patients, with these patients at an elevated risk of NTG, which was not mediated by blood pressure.

Thyroid Eye Disease and Glaucoma: A Cross-Sectional Study Comparing Clinical Characteristics and Disease Severity.

Background and Objectives: This study investigates the relationship between thyroid eye disease (TED) and open-angle glaucoma (OAG), focusing on disease severity and clinical features. Materials and Methods: Conducted at the Timis County Emergency Clinical Hospital, the research included 106 patients, with 53 having both conditions and 53 having only OAG. Key metrics analyzed included intraocular pressure (IOP) using a Goldmann applanation tonometer, the retinal nerve fiber layer (RNFL) thickness, and optic nerve head (ONH) characteristics evaluated using optical coherence tomography (OCT). Results: Results indicated that patients with both TED and OAG experienced a 6.09% reduction in RNFL thickness and showed more rapid disease progression, with 48.35% having active TED. The mean IOP in TED patients was 27.5 ± 4.9 mmHg, which was similar to those with only OAG. Demographic factors, including age and gender, influenced the clinical course and disease severity. Conclusions: These findings underscore the importance of specialized monitoring and treatment strategies for patients with coexisting TED and OAG to prevent vision loss.

The Impact of Intraocular Pressure Changes on Corneal Biomechanics in Primary Open-angle Glaucoma

PurposeTo investigate the relationship between intraocular pressure (IOP) changes and corneal biomechanical properties, determine the quantitative relationship between IOP changes and corneal biomechanical properties in patients with glaucoma and observe the differences among different types of glaucoma when the effects of high-level IOP were excluded. DesignProspective clinical cohort study. MethodsSetting: Institutional. Patients: Treatment-naive patients with primary open-angle glaucoma or ocular hypertension (OHT) were included. Observation Procedures: IOP was measured using a Goldmann applanation tonometer. Corneal biomechanics were evaluated using a corneal indentation device and corneal visualization Scheimpflug technology. Medication therapy was used for IOP reduction. Repeated measurements were taken at the baseline visit and each week thereafter within a month. Paired t tests were used to compare IOP and corneal biomechanical metrics before and after IOP-lowering therapy. One-way analysis of variance was employed to investigate potential differences across groups, with a Bonferroni post hoc correction administered for multiple intergroup comparisons. Main Outcome Measures: Corneal biomechanical parameters following IOP changes. ResultsEighty-one participants (mean age, 41.63 ± 17.33 years) were included in this study. The cohort comprised 20 patients with normal-tension glaucoma (NTG), 47 with high-tension glaucoma (HTG), and 14 with OHT. The baseline corneal stiffness (88.58±18.30 N/m) and corneal modulus (0.71±0.16 MPa) were greater than the post-IOP reduction values (67.15±9.24 N/m and 0.54±0.08 MPa, respectively; P<0.001). The relationships between changes in IOP and changes in corneal biomechanical parameters were Δ corneal stiffness=2.06*ΔIOP+6.47 (P<0.001) and Δ corneal modulus=0.017*ΔIOP+0.051 (P<0.001). After IOP reduction, the mean corneal stiffness at the 4th week in the NTG group was significantly lower (60.97±6.36 N/m) than that in the HTG (67.25±9.01 N/m) and OHT (75.62±6.52 N/m, P < 0.001) groups. Additionally, the stiffness of HTG patients was lower than that of OHT patients (P = 0.003). ConclusionsChanges in IOP have an impact on corneal biomechanical parameters. Decreases in corneal stiffness and modulus were observed after IOP reduction. When the effect of high-level IOP was excluded, corneal biomechanics varied according to the type of glaucoma. The HTG corneas were softer than the OHT corneas, and the NTG corneas were even softer.

Glaucoma Home Self-Testing Using VR Visual Fields and Rebound Tonometry Versus In-Clinic Perimetry and Goldmann Applanation Tonometry: A Pilot Study.

This pilot study aimed to assess the feasibility, accuracy, and repeatability of unsupervised, at-home, multi-day glaucoma testing using the Olleyes VisuALL Virtual Reality Platform (VRP) and the iCare HOME handheld self-tonometer. Participants were trained to use two U.S. Food and Drug Administration-registered or approved devices before conducting self-tests at home over 3 consecutive days. The iCare HOME intraocular pressure (IOP) measurements were collected four times daily per eye, and VRP visual field tests were performed once daily. The results were compared with one in-clinic Humphrey Field Analyzer (HFA) visual field test performed on the day of device training, iCare HOME measurements by the trainer, and the last five Goldmann applanation tonometer (GAT) results. Of 15 enrolled participants, nine of them (60%) completed the study. The six excluded participants could not self-measure using iCare HOME. There was significant correlation between the average mean deviation (MD) values of the at-home VRP tests and in-clinic HFA test (r2 = 0.8793, P < 0.001). Additionally, the average of the sensitivities in five of six Garway-Heath sectors were significantly correlated. VRP test duration was also shorter than in-clinic HFA testing (P < 0.001). Finally, at-home tonometry yielded statistically similar values compared to trainer-obtained iCare HOME values. The mean and range of at-home tonometry were also statistically similar to those for in-clinic GAT, but at-home tonometry demonstrated higher maximum IOP values (P = 0.0429). Unsupervised, at-home, multi-day glaucoma testing using two devices resulted in the capture of higher maximum IOPs than in the clinic and good MD correlation of VRP with HFA. However, 40% of participants could not self-measure IOP using iCare HOME. The study findings suggest that at-home remote glaucoma monitoring correlates with in-office testing and could provide additional information for glaucoma management, although patients had more difficulty with the iCare HOME than the VRP.

Comparability analysis of the HNT-1P Huvitz non contact tonometer for the measurement of intraocular pressure.

To evaluate the diagnostic validity of the HNT-1P non-contact tonometer (Huvitz) as a tool for accurately measuring intraocular pressure (IOP) in patients with healthy eyes, compared to the Goldmann applanation tonometer (GAT), which is the Gold Standard method for measurement of IOP. Observational, descriptive, transversal study using 148 eyes of 74 healthy patients without a diagnosis of glaucoma or other ophthalmological diseases. Three measurements of IOP were taken in each eye, using three tonometers: HNT-1P, ICR100, and GAT. The median IOP (quartiles) and mean IOP (SD) its statistical significance were calculated, and comparisons were made between the mean and median IOP values found in three groups: GAT-HNT, GAT-ICR, and HNT-ICR. The difference in mean and median IOP was analyzed in each of the three study groups, and its statistical significance and concordance correlation coefficient (CCC) were calculated. The median IOP with HNT-1P was statistically significantly lower than the median IOP with GAT, (1.1 mmHg, p < 0.001). The median IOP with HNT-1P was also lower than the median IOP with ICR100. As an additional result, the median IOP with GAT was lower than the median IOP with ICR. The CCC was moderate for HNT-ICR (0.72) and low for GAT-HNT and GAT-ICR (0.43 and 0.38, respectively). HNT-1P (Huvitz) provides statistically significantly lower IOP values than those obtained with GAT. HNT-1P could be used for screening of ocular hypertension in postoperative patients. The IOP measurement obtained with HNT-1P should be confirmed with GAT. HNT-1P yields lower IOP values than those obtained with ICR.

Accuracy of a novel method for IOP measurement without applying pressure on the cornea

PurposeTo assess the accuracy of a prototype novel instrument for intra ocular pressure (IOP) measurements not involving corneal pressure application.DesignProspective case control study.MethodsAn institutional study including 16 healthy volunteers without ocular pathology. IOP in both eyes of the participants was measured four times in different body positions with the novel prototype and reference instrument (Goldmann applanation tonometer (GAT) or iCare (iCare Finland OY, Vantaa, Finland)). IOP results were compared between the prototype and the reference instruments in 116 pairs of measurement.ResultsOverall no statistically significant difference was found between the presented prototype and the reference instrument. Stratifying measurements by instrument used revealed no significant difference for GAT and statistical significant (yet clinically insignificant) difference for iCare.ConclusionsThe presented prototype demonstrates good clinical agreement of IOP measuring results with reference instruments Further large-scale studies assessing this instrument in glaucoma patients are warranted.

Comparison of intraocular pressure measurements with the tono-pen, goldmann applanation tonometer, and noncontact tonometer in nonglaucomatous pseudophakic children.

To evaluate the agreement between the Goldman applanation tonometer (GAT), Tono-Pen, and noncontact tonometer (NCT) in the measurement of intraocular pressure (IOP) in pseudophakic children. The medical records of nonglaucomatous pseudophakic children between 2009 and 2019 were retrospectively analyzed. A total of 46 eyes of 23 patients operated for bilateral pediatric cataract were included in the study. The patients' mean age was 13.4 ± 4.1years. Central corneal thickness (CCT) and IOP values measured with the GAT, Tono-Pen, and NCT were recorded. Agreement between the tonometers was evaluated by intraclass correlation coefficients (ICC) and the Bland-Altman method. The mean IOP of the 46 eyes included in the study was measured as 13.7 ± 2.3mm Hg with the GAT, 16.0 ± 2.3mm Hg with NCT, and 16.5 ± 2.3mm Hg with the Tono-Pen (p < 0.001). There is no statistical difference between NCT and Tono-Pen measurements, while GAT measurements were significantly lower than those of the NCT and Tono-pen. ICC values showed fair agreement between NCT and Tono-Pen (ICC = 0.720), whereas there was poor agreement between GAT and NCT (ICC = 0.501) and Tono-pen (ICC = 0.314). With all devices included in the study, thicker corneas were associated with higher IOP measurements. Although there was moderate agreement between the NCT and Tono-Pen, there was a statistically significant difference in the IOP values provided by the three devices. Our results suggest these devices should not be used interchangeably.

Effect of topical brinzolamide on visual function and waveform in patients of infantile nystagmus syndrome: A randomized control trial.

To evaluate the effect of topical carbonic anhydrase inhibitor (brinzolamide) versus placebo on visual function and waveforms in infantile nystagmus syndrome (INS). Prospective, placebo-controlled, double-blind, cross-over study. Setting- A tertiary eye care center. Patients- Cases of idiopathic INS with and without abnormal head posture aged ≥10 years who had not received previous treatment for nystagmus. Intervention- Patients were randomized into two groups. Group 1 was given placebo for 3 months, and after a washout period of 7 days started on topical brinzolamide for the next 3 months. In group 2, the order was reversed. The drops were administered topically three times (every 8 hours) in both eyes. Outcome measure- Binocular best corrected visual acuity (BCVA) using the ETDRS chart, eXpanded nystagmus acuity function (NAFX) score and INS waveforms obtained from eye movement recordings, intraocular pressure (IOP) by Goldmann applanation tonometer, near stereopsis by TNO stereo test, and change in abnormal head posture before and after intervention in the null position. A total of 29 cases completed the study (23 with abnormal head posture; 6 without abnormal head posture). While brinzolamide shows improvement in visual acuity and NAFX score in idiopathic INS, its clinical significance needs further evidence.

Evaluation of a new transpalpebral tonometer for self-measuring intraocular pressure.

We developed a novel transpalpebral self-tonometer called the TapEye tonometer (TET) based on palpation of the upper eyelid. Our goal was to evaluate a method for improving the accuracy of measuring intraocular pressure (IOP) through the eyelid. Participants underwent standardized training by technicians and were required to be able to use the TET for study inclusion. Subsequently, a noncontact tonometer and Goldmann applanation tonometer (GAT) were used. All participants were instructed to measure their IOPs using the three tonometers at baseline (visit 1) and at 1 month (visit 2). At visit 2, the corrected IOP value measured by the TET (c-TET) was calculated using the difference between the TET and GAT measurements obtained at visit 1. No significant correlations were found between the TET and GAT measurements at any visit, but the correlation between the c-TET and GAT measurements at visit 2 was significant. The mean difference between the c-TET and GAT measurements was 0.4 ± 3.7 mmHg in the right eye and 0.5 ± 3.4 mmHg in the left eye. After correcting the IOP based on the difference between the TET and GAT measurements at the initial visit, the corrected IOP value of the TET was correlated with that of the GAT at the second visit. The TET has the potential to address an unmet need by providing a tool for minimally invasive IOP measurements. Clinical trial registration number: jRCTs032220268.

Effects of Hemodialysis on Intraocular Pressure and Ocular Perfusion Pressure.

Elevated intraocular pressure (IOP) and reduced ocular perfusion pressure (OPP) related to hemodialysis (HD) are risk factors for the development and progression of glaucoma. The aim of this study was to evaluate the effect of HD on IOP and OPP in our patients. This was a cross-sectional, descriptive, and analytical study conducted between January 2 and February 5, 2024, in the HD and ophthalmology departments of the Heinrich Lübke Regional Hospital in Diourbel. The IOP of both eyes was measured one hour before the start of the HD session and within 30 minutes after the end of the session, by the same ophthalmologist, for all included patients, using a Goldmann applanation tonometer. OPP were calculated and other socio-demographic data collected. Fifty-eight eyes from 29 chronic HD patients were included. The mean age of the patients was 47.58±12.94 years, with a predominance of women (17 women or 58.6%; sex ratio 0.71). In the left eye, mean IOP increased significantly from 12.21±2.96 mmHg before the HD session to 14.10±4.27 mmHg at the end of the session (p=0.04). For the right eye, the IOP also increased with a strong tendency to significance from 12.97±3.79 mmHg before the HD session to 15.03±5.23 mmHg at the end of the session (p=0.05). OPP did not change significantly after the HD session. The HD session significantly increased IOP with no significant change in OPP.

Effect of Dorzolamide-Timolol fixed dose combination on central Corneal Thickness in patients of Primary Open Angle Glaucoma Versus Normal Tension Glaucoma

PURPOSE: To evaluate the effect of dorzolamide/timolol fixed dose combination on central corneal thickness in primary open-angle and normal tension glaucoma. METHOD: This retrospective cohort study was approved by the Ethical Review Board of College of Ophthalmology and Allied vision Sciences (1469/23) and was conducted at Diagnostic clinic Mayo Hospital, Lahore from March, 2023 to September, 2023. Sample size was calculated by a formula whose level of significance (????) was 5%, standard deviation (????) 30.9 and test values of population mean (µ̥) was 540. Using non-probability convenient sampling method total sample size was 80 patients of age group 30 to 60 which divided into normal tension and primary open angle glaucoma of 40 each. Patients with corneal edema, diabetes, and allergic to dorzolamide-timolol fixed dose combination were excluded. Data was analyzed using SPSS version 25.00. Wilcoxon signed ranks test and chi-square test were used for the significance of the study. Data p-value &lt;0.005 considered significant. All the tests were performed after patient’s informed consent. Intraocular pressure (IOP) and central corneal thickness (CCT) were measured by Goldmann applanation tonometer and ultrasound Pachymeter respectively. RESULTS: IOP and CCT in right eye 16.17± 7.05 (p=0.000) and 545.50± 22.2 (p=0.098) respectively and of left eye 16.56± 7.00 (p=0.003) and 549.16± 20.0 (p=0.133) respectively. This illustrates significant difference in intraocular pressure after treatment in both eyes but insignificance difference in central corneal thickness. CONCLUSION: Dorzolamide-Timolol combination successfully reduces IOP as intended and leads to no statistically significant change in central corneal thickness.

ACCURACY OF MEASUREMENT RESULTS ON SCHIOTZ TONOMETER TOWARDS GOLDMANN APPLANATION TONOMETER IN TYPE II DIABETES MELLITUS PATIENTS IN MOHAMMAD HOESIN HOSPITAL, PALEMBANG

Introduction &amp; ObjectivesThe Goldmann Applanation Tonometer is now the most accurate gold standard compared to othertonometers. IOP measurement errors using the Schiotz Tonometer can be caused by ocular rigidity,where the IOP is read higher in eyes with higher ocular rigidity and vice versa. Type II DiabetesMellitus (DM) patients are at risk for increased ocular rigidity&#x0D; MethodsThis research is a cross-sectional study with a diagnostic test design regarding the accuracy ofintraocular pressure results on the Schiotz Tonometer against the Goldmann Applanation Tonometerin type II Diabetes Mellitus patients with 35 research samples. The research was conducted at theMohammad Hoesin Hospital in Palembang from April 2022 – September 2022 until the sample sizewas met&#x0D; ResultsIntraocular pressure (IOP) as measured by The average Goldmann Applanation Tonometer was 15.5± 2.4 mmHg, with a Schiotz load of 7.5 grams the average was 16.2 ± 2.3 mmHg. Ocular rigidityhad a median of 0.0242 (0.0176 – 0.0341) From the results of this study the IOP examination withthe Schiotz Tonometer had a sensitivity of 92.9%, a specificity of 80.9%, a positive predictive valueof 76.5%, a negative predictive value of 94.4% and an accuracy value of 92.3% indicating astatistically strong level of accuracy&#x0D; ConclusionThe Schiotz tonometer has an accuracy rate of 92.3% in examining intraocular pressure using a loadof 7.5 type II diabetes patients which can replace the Goldmann Applanation Tonometer as the goldstandard if normal ocular rigidity is found

The effect of 1% tropicamide on central corneal thickness and intraocular pressure

Background: Dilating the eye with tropicamide may alter the intraocular pressure (IOP) because of an obstruction of the iridocorneal angle, resulting in decreased aqueous outflow drainage. Also, the repeated application of eyedrops and instrumentation could lead to increased central corneal thickness (CCT), consequently affecting IOP.Aim: This study aimed to determine the effect of 1% tropicamide on CCT and IOP post-mydriasis among the University of Limpopo optometry students.Setting: The data were collected at the optometry clinic of the University of Limpopo.Methods: A within-subject experimental study was conducted on 59 healthy subjects aged 18 years – 28 years. A computer assisted simple random probability sampling was used to identify a sample of participants from the study population (N = 200). Baseline and post-mydriasis IOP (20 min, 30 min, and 45 min intervals) were measured with a Goldmann applanation tonometer. Central corneal thickness and IOP were analysed using means, correlations and paired t-tests.Results: The mean CCT pre-mydriasis was 504.68 μm, and post-dilation was 507.90 μm, 510.08 μm and 509.25 μm at 20 min, 30 min, and 45 min, P = 026, p = 0.033, P = 0.004, respectively. Moreover, the mean IOP pre-mydriasis was 15.97 mmHg, and post-dilation was 16.85 mmHg, 16.46 mmHg and 16.85 mmHg over 20 min, 30 min, and 45 min of followed-up time, p = 0.140, p = 0.432, and p = 0.183, respectively.Conclusion: Measuring IOP post-dilation is still valid; however, CCT should be measured before the instillation of tropicamide.Contribution: This study analysed the effect of 1% tropicamide on CCT and IOP post-mydriasis in a clinical South African context.