Amount Of Intraocular Pressure Reduction Research Articles

Intraocular pressure reduction and progression of highly myopic glaucoma: a 12-year follow-up cohort study

AimsTo investigate any association between intraocular pressure (IOP) reduction amount and open-angle glaucoma (OAG) progression in highly myopic eyes and to determine the associated risk factors.MethodsOne hundred and thirty-one (131)...

Trabecular Procedures Combined with Cataract Surgery for Open-Angle Glaucoma: A Report by the American Academy of Ophthalmology

To determine the intraocular pressure (IOP) reduction of various trabecular procedures (a form of minimally invasive glaucoma surgery [MIGS]) combined with cataract surgery compared with cataract surgery alone, to compare the safety of the various trabecular procedures, and to highlight patient characteristics that may favor one trabecular procedure over another. A search of English-language peer-reviewed literature in the PubMed database was initially conducted in February 2021 and updated in April 2023. This yielded 279 articles. Twenty studies met initial inclusion and exclusion criteria and were assessed for quality by the panel methodologist. Of these, 10 were rated level I, 3 were rated level II, and 7 were rated level III. Only the 10 level I randomized controlled trials (RCTs) were included in this assessment, and all were subject to potential industry-sponsorship bias. The current analysis focuses on the amount of IOP reduction (in studies that involved medication washout) and on IOP reduction with concurrent medication reduction (in studies that did not involve medication washout). Based on studies that performed a medication washout, adding a trabecular procedure to cataract surgery provided an additional 1.6 to 2.3 mmHg IOP reduction in subjects with hypertensive, mild to moderate open-angle glaucoma (OAG) at 2 years over cataract surgery alone, which itself provided approximately 5.4 to 7.6 mmHg IOP reduction. In other words, adding a trabecular procedure provided an additional 3.8% to 8.9% IOP reduction over cataract surgery alone, which itself provided 21% to 28% IOP reduction. There was no clear benefit of one trabecular procedure over another. Patient-specific considerations that can guide procedure selection include uveitis predisposition, bleeding risk, metal allergy, and narrowing of Schlemm's canal. There are no level I data on the efficacy of trabecular procedures in subjects with pretreatment IOP of 21 mmHg or less. Trabecular procedures combined with cataract surgery provide an additional mild IOP reduction over cataract surgery alone in hypertensive OAG subjects. Additional research should standardize outcome definitions, avoid industry sponsorship bias, and study the efficacy of these procedures in normotensive OAG. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Lens parameters as predictors of intraocular pressure changes after phacoemulsification.

To evaluate intraocular pressure (IOP) change after cataract surgery in non-glaucomatous eyes with narrow and open angles (OAs) and its relation to novel lens parameters measured by anterior segment optical coherence tomography (AS-OCT). University affiliated hospital, Farabi Eye Hospital, Tehran, Iran. Prospective interventional case series. In this prospective study, 85 non-glaucomatous eyes underwent phacoemulsification and lens implantation. Thirty-nine eyes had OAs and 46 eyes had narrow angles (NAs). IOP and biometric parameters were measured by AS-OCT preoperatively and 3 months after surgery. Change in IOP and its relation to biometric parameters, including lens vault (LV), anterior vault (AV), defined as the sum of the LV and the ACD, and relative LV (rLV), defined as the ratio of the LV to the AV, were evaluated. The main outcome measure was degree of IOP change after phacoemulsification. Of the 85 patients included in the analysis, 35 were male and 50 were female with an overall mean age of 62.2 ± 8.9 years. The average IOP reduction was -4.95 ± 2.26 mm Hg, from a preoperative mean of 17.12 ± 2.47 mm Hg, at 3 months after cataract surgery. The amount of IOP reduction was significantly greater in the NA compared with the OA group. In multivariate linear regression analysis, preoperative IOP and AV were significantly associated with IOP decrease (all ≤ 0.03). Cataract surgery results in IOP reduction in both OA and NA eyes. The amount of IOP reduction is related to AV.

Contralateral intraocular pressure lowering effect of prostaglandin analogues.

Background:Though the use of prostaglandin analogues (PGA) for reduction of intraocular pressure (IOP) has shown a marked increase, studies evaluating the contralateral effects of PGA are limited.Aims:To evaluate if PGA treatment in one eye has an effect on the IOP of the untreated fellow eye.Design:Retrospective study.Materials and Methods:Thirty patients of open-angle glaucoma with no previous antiglaucoma treatment underwent 24-hour diurnal IOP phasing. They subsequently were started on a uniocular trial with PGA, and had office diurnal IOP measurements 6 weeks later. Twenty-four hour diurnal consisted of 8 IOP readings over 24 hours and office diurnal consisted of 4 IOP readings between 8 AM and 6 PM at 3 hourly intervals.Statistical Analysis:IOPs of the fellow eye during the office diurnal were compared with IOPs at similar time points during the 24-hour diurnal using paired t-tests.Results:Mean (± standard deviation) IOP in the treated eye reduced (P < 0.001) from 17.17 ± 3.2 mm Hg at baseline to 13.7 ± 2.4 mm Hg at 6 weeks, while that in the untreated eye reduced from 16.4 ± 3.1 mm Hg to 14.8 ± 2.7 mm Hg (P = 0.01). The decrease in IOP in the untreated fellow eye was statistically significant at 8 AM (2.7 mm Hg, P = 0.003) and 11 AM (2.3 mm Hg, P = 0.01) but not so at 2 PM (1.2 mm Hg, P = 0.10) and 5 PM (0.9 mm Hg, P = 0.19). The amount of IOP reduction in the untreated eye was significantly associated with the magnitude of IOP reduction in the treated eye (β = 0.69, P = 0.008).Conclusion:Uniocular PGA treatment tends to reduce the IOP of the untreated fellow eye.

Intraocular pressure reduction with topical medications and progression of normal‐tension glaucoma: a 12‐year mean follow‐up study

To investigate whether the amount of intraocular pressure (IOP) reduction with topical medications is associated with the progression of normal-tension glaucoma (NTG) and to identify risk factors for NTG progression. The medical records of 121 eyes of 121 NTG patients, who were treated with topical medications for more than 7 years, were reviewed. NTG progression was defined by either structural (optic disc or retinal nerve fibre layer) or functional (visual field) deterioration. Patients were divided into tertile groups according to the percentage IOP reduction from baseline, and the cumulative probability of NTG progression between upper and lower tertile group was compared using Kaplan-Meier survival analysis. Multivariate analysis with Cox's proportional hazard model was performed to identify the hazard ratio (HR) of clinical factors for NTG progression. The average follow-up period was 12.2 years, and 56 of 121 eyes (46.3%) showed the NTG progression. Kaplan-Meier analysis revealed that upper tertile group (percentage IOP reduction >22.1%) showed a greater cumulative probability of non-progression than lower tertile group (percentage IOP reduction < 13.3%; p = 0.012). Multivariate Cox's proportional hazard model indicated that percentage reduction of IOP (HR = 0.964; p = 0.007) and the occurrence of disc haemorrhage (HR = 2.410; p = 0.008) were significantly associated with NTG progression. The amount of IOP reduction using topical medications was related to NTG progression, and lower percentage reduction in IOP was a consistent risk factor for progression.

Intravenous hypertonic saline reduces intraocular pressure

Abstract Purpose To study the effect of intravenous hypertonic saline (HTS) solution on intraocular pressure (IOP). Methods Nineteen patients (mean age ±SD, 66 ± 11 years) with glaucoma and IOP ≥30 mmHg were recruited. HTS solution with sodium chloride concentration of 7,5% (Natriumklorid Braun 234 mg/ml, B.Braun Medical Oy, ) was given intravenously in an antecubital vein. IOP was measured every minute for 10 minutes and less frequently for up to 2 hours after treatment. The dosage given was 0,5 mmol/kg in 11 patients (Group05) and 1,0 mmol/kg in eight patients (Group1). Results The maximum mean (±SD) IOP reduction was achieved 5 minutes after treatment at which point mean IOP had reduced from 40 ± 11 mmHg before treatment to 33 ± 12 mmHg (P &lt; 0.001). The mean percentage IOP reduction was 20 ± 10 % (range 8% – 40%) and the absolute IOP reductions ranged 4 to 16 mmHg. Two hours after treatment, mean IOP was still reduced to 33 ± 13 mmHg (P&lt; 0.001). There was no difference between Group05 and Group1 in the amount of IOP reduction, but there was a trend that the IOP reduction sustained longer in Group1. Four patients reported mild to severe pain in the arm after injection. Especially patients in Group1 had a feeling of warmth in the head and neck region. These symptoms lasted for 1‐2 minutes. Conclusion Intravenous HTS solution reduces IOP within minutes after injection.

Meta-analysis of 1- versus 2-Site Phacotrabeculectomy

Comparison of efficacy of intraocular pressure (IOP) reduction between 1- versus 2-site phacotrabeculectomy. The last systematic review concluded that there was weak evidence to suggest that 2-site phacotrabeculectomy provides 1- to 2-mmHg lower IOP than 1-site surgery. Since this study, there have been further publications on this topic, stimulating this meta-analysis. Randomized controlled trials comparing 1- versus 2-site phacotrabeculectomy were searched through August 2009 using MEDLINE and the Cochrane Registry with the keyword phacotrabeculectomy. Inclusion criteria were prospective randomized controlled trials, a minimum of 12 months of follow-up, and English language. Quality of the trials was assessed using Cochrane collaboration's tool of assessing risk of bias. The main outcome measure was IOP, and secondary outcomes included number of glaucoma medications, visual acuity, complications, and surgical time. Ten articles were included. There was no statistically significant difference in the amount of IOP reduction between 1- and 2-site phacotrabeculectomy. The pooled IOP decreases from baseline (95% confidence interval) were: 7.85 mmHg (6.76-8.92 mmHg) versus 5.83 mmHg (4.72-6.94 mmHg) at 1 month; 8.03 mmHg (7.38-8.67 mmHg) versus 7.03 mmHg (6.35-7.71) at 3 months; 7.78 (7.14-8.42) versus 6.75 (6.04-7.46) at 6 months; 6.44 (5.47-7.41 mmHg) versus 6.68 mmHg (5.56-7.81 mmHg) at 12 months; 7.17 mmHg (6.45-7.89 mmHg) versus 6.56 mmHg (5.77-7.35 mmHg) at 24 months; and 7.76 mmHg (7.02-8.49 mmHg) versus 7.14 mmHg (6.36-7.92 mmHg) at 36 months for 1- versus 2-site phacotrabeculectomy, respectively. There was no significant difference in the reduction in glaucoma medications or change in visual acuity at any time point. There is no significant difference in IOP reduction between 1- and 2-site phacotrabeculectomy.

Comparing two tensioning suture sizes for 360° viscocanalostomy (canaloplasty): a randomised controlled trial

To compare the safety and efficacy of two polypropylene (Prolene) sutures for tensioning of the inner wall of Schlemm's canal (SC) in black African patients with primary open-angle glaucoma (POAG) undergoing canaloplasty. In a prospective randomised trial of 90 patients, canaloplasty was performed with a flexible microcatheter (iTrack-250A) and sodium hyaluronidate 1.4% (Healon GV). After complete circumferential dilatation of the SC, a Prolene suture, either 6-0 Prolene (group 1) or 10-0 Prolene (group 2), was retracted through the SC and tightened leaving tension on the canal and trabecular meshwork. Nd:YAG laser goniopuncture was not performed postoperatively. The mean preoperative intraocular pressure (IOP) was 42.7 mm Hg+/-12.5 (SD) in group 1 and 45.0 mm Hg+/-12.1 (SD) in group 2 (P=0.70). The mean postoperative IOP without medications was 18.4 mm Hg+/-7.1 (SD) in group 1 and 16.4 mm Hg+/-6.6 (SD) in group 2 at 1 month (P=0.10), 19.2 mm Hg+/-6.4 (SD) in group 1 and 16.4 mm Hg+/-4.9 (SD) at 15 months (P=0.04). Pressures equal or less than 21, 18, and 16 mm Hg without medications (complete success) at 12 months were 51.0% (95% confidence interval (CI) 0.35-0.73), 34.1% (95% CI 0.21-0.56), and 21.2% (95% CI 0.11-0.42) in group 1, and 76.9% (95% CI 0.62-0.96), 68.8% (95% CI 0.54-0.89), and 53.6% (95% CI 0.38-0.76) in group 2, respectively. In the Cox regression analysis, IOP<18 mm Hg without medications depended significantly on the type of Prolene (hazard ratio (HR) 2.60, 95% CI 1.24-5.46, P=0.01) and age (HR 1.3, 95% CI 1.03-1.86, P=0.03), but not on preoperative IOP (HR 1.01, 95% CI 0.99-1.04, P=0.16) and gender (HR 0.67, 95% CI 0.34-1.33, P=0.26). No filtering bleb was observed. Intra- and postoperative complications were similarly rare in the two groups and included partial 'cheese-wiring' (2), Descemet's rupture (2), and hyphaema (3). In this clinical trial, IOP reduction was substantial in canaloplasty and slightly greater in combination with 10-0 Prolene than 6-0 Prolene sutures at an equally low complication rate. Younger age, but not the level of IOP at surgery, had a positive effect on the amount of IOP reduction, thus suggesting that an early surgical intervention to re-establish physiological outflow offers the best prognosis.

Is the medication used to achieve the target intraocular pressure in glaucoma therapy of relevance? – An exemplary analysis on the basis of two beta-blockers

Glaucoma, the most common optic neuropathy (GON) is characterised by the loss of retinal ganglion cells and their axons, as well as tissue remodelling of both the retina and the optic nerve head with corresponding visual field defects. Elevated intraocular pressure (IOP) is generally regarded as the major risk factor for glaucoma and its reduction is the most common target for therapy of GON. There are indications that the greater the IOP reduction, the better is the visual field prognosis. This article investigates, on the basis of two beta-blockers, betaxolol and timolol, whether the amount of IOP reduction is truly a good surrogate for successful glaucoma therapy with respect to visual field outcome. Contrary to what is generally expected, our analysis of the literature exemplifies that despite a smaller IOP reduction, patients treated with betaxolol had a smaller rate of visual field deterioration than patients treated with timolol. Based on the dissociation of IOP reduction and visual field prognosis, we postulate that for successful treatment in glaucoma not only the amount of IOP reduction is relevant but also the drug by which the reduction is achieved. This seeming paradox phenomenon highlights that ocular hypotensive drugs have relevant effects on GON other than IOP-related. Some of these effects on retinal ganglion cells (neuroprotection) or on ocular blood flow are mediated by calcium- and sodium channels. Future studies on glaucoma treatment should focus on their effect on visual field function, and not just on IOP. This should particularly be considered when comparing drugs from different classes.

The Effect of Latanoprost, Bimatoprost, and Travoprost on Circadian Variation of Intraocular Pressure in Patients With Open-angle Glaucoma

To evaluate the efficacy of latanoprost, bimatoprost, and travoprost given in the evening over the 24-hour curve in newly diagnosed open-angle glaucoma patients. This 8-week, randomized, parallel group, masked evaluator study compared the efficacy of once daily administration of latanoprost 0.005%, bimatoprost 0.03%, and travoprost 0.004% ophthalmic solutions. After enrollment at baseline, 48 patients were randomized to 3 treatment groups: latanoprost (n=17), bimatoprost (n=16), and travoprost (n=15). At baseline and 8 weeks of therapy, masked evaluators measured intraocular pressure (IOP) at 8 AM, 10 AM, 1 PM, 4 PM, 8 PM, 11 PM, and 3 AM. Baseline mean IOP levels were similar across the groups. By week 8, reductions were observed in all 3 groups (P<0.001 for each). Travoprost-treated patients' IOP levels were reduced 8.7 and 8.1 mm Hg at 8 and 10 AM, respectively. Latanoprost-treated patients experienced 4.8 and 5.3 mm Hg reductions, whereas bimatoprost-treated patients experienced 5.5 and 4.9 mm Hg reductions at these time points. The amount of IOP reduction seen at 8 and 10 AM in travoprost group was significantly higher when compared with latanoprost and bimatoprost-treated group (P<0.001). Latanoprost, bimatoprost, and travoprost were comparable in their ability to reduce IOP in open-angle glaucoma patients. On the basis of our data, the IOP reduction of these drugs is indistinguishable within statistical parameters.

Correlation Between Individual Differences in Intraocular Pressure Reduction and Outflow Facility Due to Latanoprost in Normal-Tension Glaucoma Patients

The amount of intraocular pressure (IOP) reduction achieved by the use of latanoprost eyedrops varies among patients, and there are even nonresponders. This report examines whether there is any correlation between the amount of individual variability in IOP reduction and the uveoscleral outflow facility after latanoprost eyedrop instillation in normal-tension glaucoma patients. Sixteen normal-tension glaucoma patients (mean age, 56.4 years) were enrolled in the study to investigate the relationship between the amount of IOP reduction and outflow facility. Before treatment, subjects underwent circadian IOP measurement and then tonography, and the outflow facility was calculated. Subsequently, patients began treatment once daily with latanoprost instillation in one eye. After 4 weeks of daily latanoprost treatment, circadian IOP was measured again. Mean pretreatment outflow facility was 0.23 +/- 0.05 microl/min per mmHg. On average, latanoprost instillation decreased IOP by 2.8 mmHg, but the reduction varied among individuals from -0.3 mmHg to 5.8 mmHg. No significant correlation was noted between the outflow facility and the IOP decline associated with latanoprost. Because there was no significant correlation between individual IOP reduction by latanoprost and outflow facility, the differences in substantial change in uveoscleral outflow after latanoprost administration may be one explanation for the individual variation in IOP reduction after treatment with this drug.

Trabeculectomy and optic nerve head topography

The objective of the present study was to evaluate changes in optic nerve head parameters, measured by confocal laser tomography, before and after trabeculectomy in order to identify outcome measures for the management of glaucoma. The optic nerve head of 22 eyes (22 patients) was analyzed by confocal laser tomography with the Heidelberg retinal tomogram (HRT) before and after trabeculectomy. The median time between the first HRT and surgery was 4.6 months (mean: 7.7 +/- 8.3) and the median time between surgery and the second HRT was 10.8 months (mean: 12.0 +/- 6.8). The patients were divided into two groups, i.e., those with the highest (group A) and lowest (group B) intraocular pressure (IOP) change after surgery. Differences in the 12 standard topographic parameters before and after surgery for each group were evaluated by the Wilcoxon signed rank test and the differences in these parameters between the two groups were compared by the Mann-Whitney rank sum test. Multiple regression analysis was used to evaluate the influence of the change in IOP (DeltaIOP and DeltaIOP%) and the changes in the other parameters. There were significant differences in the HRT measures before and after surgery in group A only for cup volume. In group B, no parameter was statistically different. The changes in group A were not significantly different than those in group B for any parameter (P > 0.004, Bonferroni correction for multiple comparisons). DeltaIOP and DeltaIOP% had a statistically significant effect on Delta cup disk area, Delta cup volume and Delta mean cup depth. Changes in cup shape size were influenced significantly only by DeltaIOP. Some optic disc parameters measured by HRT presented a significant improvement after filtering surgery, depending on the amount of IOP reduction. Long-term studies are needed to determine the usefulness of these findings as outcome measures in the management of glaucoma.

Corneal graft survival and intraocular pressure control after penetrating keratoplasty and glaucoma drainage device implantation

Objective To investigate corneal graft survival rates and intraocular pressure (IOP) control in eyes after penetrating keratoplasty (PK) and glaucoma drainage device (GDD) implantation. Design Retrospective, comparative, consecutive case series. Participants All patients who underwent PK and GDD implantation at the Bascom Palmer Eye Institute between January 1, 1993 and October 31, 1998. Main outcome measures Graft clarity and IOP control. Results Of the 72 eyes in 72 patients identified, 47 (65%) underwent combined PK and GDD implantation, and 25 (35%) underwent GDD placement after PK (2–30 months after PK; median, 13 months). The GDD type was Baerveldt 350 mm 2 in 57 eyes, Ahmed in 9, Krupin in 2, and other in 4 eyes. The GDD was placed in the anterior chamber in 54 eyes (75%) and in the vitreous cavity in 18 eyes (25%). Preoperative IOP was 11 to 53 mmHg with or without antiglaucoma medications in 16 eyes (30%) with the GDD implanted in the anterior chamber and in 4 eyes (22%) with the GDD placed in the vitreous cavity ( P = 0.76). At 1 year after GDD implantation, the graft was clear in 26 eyes (48%) with the GDD in the anterior chamber compared with 15 eyes (83%) with the GDD in the vitreous cavity ( P = 0.013). Forty-eight eyes (89%) with the GDD in the anterior chamber and 18 eyes (100%) with the GDD in the vitreous cavity had IOP between 5 and 21 mmHg with or without antiglaucoma medications ( P = 0.33). The mean reduction in IOP, 1 year after surgery, was 12 mmHg among eyes with the GDD in the anterior chamber, compared with 17 mmHg among eyes with the GDD in the vitreous cavity ( P = 0.13) Conclusions Corneal graft survival at 1 year is significantly higher among eyes with the GDD implanted in the vitreous cavity compared with those in which the GDD is implanted in the anterior chamber. The IOP was significantly lower at 1 year after surgery compared with before surgery in both groups, and there was no significant difference between the groups in IOP control and amount of IOP reduction. There was no significant difference in corneal graft survival or IOP control between eyes with the GDD implanted concurrently with the PK versus after the PK.

Methods to objectify reversibility of glaucomatous cupping.

Lowering intraocular pressure in adults with glaucoma may be associated with an improvement in appearance of the optic nerve head. The stage of disease, the amount of intraocular pressure reduction, and the age of the patient probably influence the occurrence of this event. The clinical relevance of "reversal" has not been established with certainty. The reversibility of glaucomatous cupping can be detected by subjective and qualitative means (examination of the patient or of fundus photographs) or by quantitative techniques such as photogrammetry, computerized image analysis, and scanning laser tomography. Clinical and experimental studies are providing new information about the behavior of the optic nerve head tissues in response to changes in intraocular pressure.

Improvement of Visual Field Indices After Surgical Reduction of Intraocular Pressure

In a prospective case series (consecutive patients) of 30 eyes from 30 subjects with medically uncontrolled glaucoma being treated at a hospital-based, referral glaucoma service, we sought to ascertain if a surgically obtained reduction of intraocular pressure (IOP) in human glaucomatous eyes is paralleled by an improvement of the visual field. Uncomplicated limbus-based trabeculectomy was performed in 13 men and 17 women familiar with computerized perimetry testing, with a pupil diameter of at least 4 mm (measured at the Goldmann perimeter bowl), a best-corrected visual acuity of 20/20 in both eyes, and a Mean Sensitivity (MS) index greater than 10 dB. The main outcomes measured were: visual field data (Octopus, program G1) and IOP (mean of the two highest values during the diurnal curve) obtained 3 days before and 3 months after surgery in both the operated and the fellow eyes. In the operated eyes, an increase of MS (from 17.2 +/- 2.4 to 18.9 +/- 2.8, P < .000001, paired samples two-tailed t test) was observed. Meanwhile, the Corrected Loss Variance (CLV) remained substantially the same (46.8 +/- 12.2 before, vs 47.3 +/- 13.4 after; P = .87, paired samples two-tailed t test). The increase in MS was positively correlated with the amount of IOP reduction (linear regression: r = 0.901, P < .00001). No statistically significant change of either MS or CLV values occurred in the fellow eyes. The correlation between the amount of IOP reduction and the increased MS suggests that, in the short term, reducing the IOP may improve visual function to some extent. The apparent lack of correlation between the amount of IOP reduction and the CLV may indicate that the depth of the preexistent glaucomatous scotomas remains unchanged.