Multimodal Imaging Techniques in Monitoring a Patient with Ocular Decompression Retinopathy

Ocular decompression retinopathy (ODR) is characterized by multiple retinal hemorrhages. It is a rare complication associated with rapid decrease of intraocular pressure (IOP). The course of ODR is usually asymptomatic and self-limiting, which was confirmed by the observation of our patient. In this study, we present a 5-month follow up of a 77-year-old woman with acute right eye (RE) filtration angle closure who developed symptoms of ODR. Clinical examination and multimodal imaging modalities, including color fundus photography, optical coherence tomography (OCT), OCT angiography (OCTA) and fluorescein angiography (FA), were used to confirm the diagnosis and performed regularly in monitoring the course of the disease. Fundus lesions in the RE included diffuse intraretinal hemorrhages in the posterior pole, which gradually resolved during follow-up time. The fundus of the left eye (LE) was normal. The patient underwent conservative therapy, laser therapy and surgery, achieving stabilization of the IOP and improvement of the local condition in the RE. Of the various multimodal imaging techniques, color fundus photography and OCT seemed to be the most specific and helpful in monitoring the patient with ODR.

Carbonic Anhydrase Inhibitor Modulation of Intraocular Pressure Is Independent of Soluble Adenylyl Cyclase

Purpose: We investigated whether a clinically used carbonic anhydrase inhibitor (CAIs) can modulate intraocular pressure (IOP) through soluble adenylyl cyclase (sAC) signaling. Methods: IOP was measured 1 h after topical treatment with brinzolamide, a topically applied and clinically used CAIs, using direct cannulation of the anterior chamber in sAC knockout (KO) mice or C57BL/6J mice in the presence or absence of the sAC inhibitor (TDI-10229). Results: Mice treated with the sAC inhibitor TDI-10229 had elevated IOP. CAIs treatment significantly decreased increased intraocular pressure (IOP) in wild-type, sAC KO mice, as well as TDI-10229-treated mice. Conclusions: Inhibiting carbonic anhydrase reduces IOP independently from sAC in mice. Our studies suggest that the signaling cascade by which brinzolamide regulates IOP does not involve sAC.

Netarsudil monotherapy as the initial treatment for open-angle glaucoma and ocular hypertension in Indian patients: A real-world evaluation of efficacy and safety

Purpose

Glaucoma is the second leading cause of blindness worldwide, affecting more than 64 million people aged 40-80. The best way to manage primary open-angle glaucoma (POAG) is by lowering the intraocular pressure (IOP). Netarsudil is a Rho kinase inhibitor, the only class of antiglaucoma medications that reorganizes the extracellular matrix to improve the aqueous outflow through the trabecular pathway.

Methods

An open-label, real-world, multicentric, observation-based 3-month study was performed for assessing the safety and ocular hypotensive efficacy of netarsudil ophthalmic solution (0.02% w/v) in patients with elevated IOP. Patients were given netarsudil ophthalmic solution (0.02% w/v) as a first-line therapy. Diurnal IOP measurements, best-corrected visual acuity, and adverse event assessments were recorded at each of the five visits (Day-1: screening day and first dosing day; subsequent observations were taken at 2 weeks, 4 weeks, 6 weeks, and 3 months).

Results

Four hundred and sixty-nine patients from 39 centers throughout India completed the study. The mean IOP at baseline of the affected eyes was 24.84 ± 6.39 mmHg (mean ± standard deviation). After the first dose, the IOP was measured after 2, 4, and 6 weeks, with the final measurement taken at 3 months. The percentage reduction in IOP in glaucoma patients after 3 months of once-daily netarsudil 0.02% w/v solution use was 33.34%. The adverse effects experienced by patients were not severe in the majority of cases. Some adverse effects observed were redness, irritation, itching, and others, but only a small number of patients experienced severe reactions, as reported in a decreasing order: redness > irritation > watering > itching > stinging > blurring.

Conclusion

We found that netarsudil 0.02% w/v solution monotherapy when used as the first-line treatment in primary open-angle glaucoma and ocular hypertension was both safe and effective.

Treating Depression in Adolescents and Young Adults Using Remote Intensive Outpatient Programs: Quality Improvement Assessment

BACKGROUND

Youth and young adults face barriers to mental health care, including a shortage of programs that accept youth and a lack of developmentally sensitive programming among those that do. This shortage, along with the associated geographically limited options, has contributed to the health disparities experienced by youth in general and by those with higher acuity mental health needs in particular. Although intensive outpatient programs can be an effective option for youth with more complex mental health needs, place-based intensive outpatient programming locations are still limited to clients who have the ability to travel to the clinical setting several days per week.

OBJECTIVE

The objective of the analysis reported here was to assess changes in depression between intake and discharge among youth and young adults diagnosed with depression attending remote intensive outpatient programming treatment. Analysis of outcomes and the application of findings to programmatic decisions are regular parts of ongoing quality improvement efforts of the program whose results are reported here.

METHODS

Outcomes data are collected for all clients at intake and discharge. The Patient Health Questionnaire (PHQ) adapted for adolescents is used to measure depression, with changes between intake and discharge regularly assessed for quality improvement purposes using repeated measures t tests. Changes in clinical symptoms are assessed using McNamar chi-square analyses. One-way ANOVA is used to test for differences among age, gender, and sexual orientation groups. For this analysis, 1062 cases were selected using criteria that included a diagnosis of depression and a minimum of 18 hours of treatment over a minimum of 2 weeks of care.

RESULTS

Clients ranged in age from 11 to 25 years, with an average of 16 years. Almost one-quarter (23%) identified as nongender binary and 60% identified as members of the lesbian, gay, bisexual, transgender, queer (LGBTQ+) community. Significant decreases (mean difference -6.06) were seen in depression between intake and discharge (t₉₆₇=-24.68; P<.001), with the symptoms of a significant number of clients (P<.001) crossing below the clinical cutoff for major depressive disorder between intake and discharge (388/732, 53%). No significant differences were found across subgroups defined by age (F_2,958=0.47; P=.63), gender identity (F_7,886=1.20; P=.30), or sexual orientation (F_7,872=0.47; P=.86).

CONCLUSIONS

Findings support the use of remote intensive outpatient programming to treat depression among youth and young adults, suggesting that it may be a modality that is an effective alternative to place-based mental health treatment. Additionally, findings suggest that the remote intensive outpatient program model may be an effective treatment approach for youth from marginalized groups defined by gender and sexual orientation. This is important given that youth from these groups tend to have poorer outcomes and greater barriers to treatment compared to cisgender, heterosexual youth.

Comparison of Ocular Biomery in Primary Open Angle Glaucoma and Non-glaucoma in South West Nigeria

Background

Glaucoma is a public health problem in Nigeria. The number of individuals affected by glaucoma in Nigeria is much higher than the individuals known to have the disease. Ocular parameters such as intraocular pressure, central cornea thickness, axial length and refractive error have all been documented as risk factors of glaucoma especially among Caucasians and African Americans, with little documentation in Africa where there's an alarming rate of blindness.

Aim and Objectives

To compare central cornea thickness (CCT), intraocular pressure (IOP), axial length (AL) and refractive state in participants with primary open angle glaucoma (POAG) and non-glaucoma in South-West Nigeria.

Materials and Methods

This hospital-based case-control study was carried out among 184 newly diagnosed POAG and non-glaucoma adult participants attending the outpatient clinic of Eleta eye institute. The CCT, IOP, AL and refractive state were measured in each participant. Test of significance between proportions in categorical variables were assessed using chi square test (χ2) in both groups. The means were compared using independent t-test while correlation between parameters were analyzed using Pearson correlation coefficient.

Results

The mean age of the POAG participants was 57.16 + 13.3 years and the mean age of the non-glaucoma participants was 54.15 + 13.4 years. The mean IOP in the POAG group was 30.2 + 8.9mmHg while non- glaucoma group was 14.2 + 2.6mmHg (P < 0.001), other ocular parameters were not significantly different in both groups. In the POAG group, decreased spherical equivalent refractive error (i.e increasing myopia) was significantly associated with increased axial length (r= -0.252, P = 0.01), but not significant in the non- glaucoma group. However, in the non-glaucoma group, central cornea thickness increased with increasing intraocular pressure (r= 0.305, P = 0.003), which was not significant in the glaucoma group.

Conclusion

Patients with POAG had much higher IOP and thus, IOP remains a significant risk factor in its development. There was a significant relationship between refractive state and axial length in the POAG group while a significant relationship was identified between central cornea thickness and intraocular pressure in the non- glaucoma group.

Cationic liposomes as promising vehicles for timolol/brimonidine combination ocular delivery in glaucoma: formulation development and in vitro/in vivo evaluation

Glaucoma is a chronic eye disease in which the pressure inside the eye increases and leads to damage to the optic nerve, and eventually causes blindness. In this disease, it is often necessary to use a multi-drug treatment system. There is a fixed combination of timolol maleate and brimonidine tartrate among the combination drugs in glaucoma treatment. Liposomes are one of the most important targeted drug delivery systems to eye tissue, which leads to improved drug permeability and durability in ocular tissue. In this study, thin layer hydration was used to make liposomal formulations containing timolol maleate (TM) and brimonidine tartrate (BT). After the necessary evaluations, one of the eight initial formulations was selected as an optimization formulation. Then, characteristics such as drug loading percentage, particle size, pH, zeta potential, and drug release were performed on the optimized formulation. The study of reducing intraocular pressure was performed on the optimized formulation. This study in total was performed on 18 rabbits in three groups. Hydroxypropyl methylcellulose (HPMC) polymer was injected into the anterior chamber to experimental induce glaucoma. The selected formulation was within the acceptable range of ocular products in terms of physical properties. HPMC polymer injection successfully induced glaucoma in the animal model, resulting in a 79% increase in intraocular pressure. The results showed that the liposomal formulation significantly reduced the intraocular pressure compared to the simple formulation of the aqueous solution, and both formulations were able to significantly reduce the intraocular pressure compared to the control group (P < 0.001). The results also showed that liposomal formulation has a therapeutic effect in reducing intraocular pressure. It seems that the selected liposomal formulation made by thin layer hydration can act as a suitable drug carrier to increase the effectiveness of the fixed combination of timolol maleate and brimonidine tartrate and be proposed as a new drug formulation for targeted and controlled drug delivery in the treatment of glaucoma.

Risk of Intraocular Pressure Increase With Intravitreal Injections of Vascular Endothelial Growth Factor Inhibitors: A Cohort Study

PURPOSE

Intraocular pressure increase (IOPi) after intravitreal injections of vascular endothelial growth factor inhibitors (VEGFis) might be different among different VEGFis (bevacizumab, aflibercept, ranibizumab). The purpose of this study was to evaluate the risk of IOPi among new users of bevacizumab, ranibizumab, and aflibercept in nondiabetic patients in Tuscany, Italy.

DESIGN

Retrospective cohort study.

METHODS

Tuscan regional administrative database was used to identify subjects with a first VEGFi intravitreal injection between 2011 and 2020, followed to first incidence of IOPi. Diabetic subjects, those with pre-existing IOPi, or previous use of dexamethasone implants were excluded. Multivariable Cox regression analyses (intention-to-treat and as treated) were conducted to evaluate risk of IOPi among aflibercept, bevacizumab, and ranibizumab, adjusting for potential confounding variables. IOPi was defined as the first record of International Classification of Diseases, Ninth Revision (ICD-9-CM) code 365 or use of 2 glaucoma drugs dispensations within 180 days of each other.

RESULTS

We identified 6585 new users of VEGFis: 1749 aflibercept, 1112 bevacizumab, and 3724 ranibizumab. Women made up 60% of the cohort, with a mean age of 73.6 years. In the intention-to-treat analysis, the adjusted hazard ratio (HR) for incident IOPi, compared with aflibercept, was higher for bevacizumab (HR = 2.20, 95% CI = 1.64-2.95) and ranibizumab users (HR = 1.88, 95% CI = 1.46-2.42), respectively. The HRs remained robust after exclusion of patients with proxy of retinal vascular occlusion. As treated analysis confirmed such results (bevacizumab: HR = 3.76, 95% CI = 2.30-6.17; ranibizumab: HR = 2.49, 95% CI = 1.62-3.82).

CONCLUSIONS

This study found an increased risk of IOPi among nondiabetic patients with ranibizumab and bevacizumab compared with aflibercept. Future studies are needed to validate these findings.

Glaucoma and Myopia: Diagnostic Challenges

The rising global prevalence of myopia is a growing concern for clinicians, as it predisposes patients to severe ocular pathologies including glaucoma. High myopia can be associated with clinical features that resemble glaucomatous damage, which make an accurate glaucoma diagnosis challenging, particularly among patients with normal intraocular pressures. These patients may also present with established visual field defects which can mimic glaucoma, and standard imaging technology is less useful in disease detection and monitoring due to the lack of normative data for these anatomically unique eyes. Progression over time remains the most critical factor in facilitating the detection of early glaucomatous changes, and thus careful longitudinal follow-up of high-risk myopic patients is the most important aspect of management. Here, we review our current understanding of the complex relationship between myopia and glaucoma, and the diagnostic challenges and limitations of current testing protocols including visual field, intraocular pressure, and imaging. Furthermore, we discuss the clinical findings of two highly myopic patients with suspected glaucoma.

Analyzing Longitudinal Data from Glaucoma Trials

In glaucoma trials, patients often come in for multiple visits, and at each visit, intraocular pressures are taken at multiple timepoints throughout the day. A mixed model for repeated measures is often used to model the data from such trials. One modeling approach is to jointly model all visits and timepoints together. Another modeling approach is to model data across all visits at each timepoint separately. I conducted a simulation study to compare the two modeling approaches. The results suggest that modeling each timepoint separately across all visits is superior, especially when missing data are low. This approach is recommended over jointly modeling all visits and timepoints together.

EYEMATE-SC Trial: Twelve-Month Safety, Performance, and Accuracy of a Suprachoroidal Sensor for Telemetric Measurement of Intraocular Pressure

PURPOSE

Measuring and controlling intraocular pressure (IOP) provide the foundation for glaucoma treatment. Self-tonometry has been proposed as an alternative to measure IOP throughout the entire day better. The novel EYEMATE-SC sensor (Implandata) is implanted in the suprachoroidal space to enable contactless continual IOP monitoring. The aim of the present study was to investigate the 1-year safety, performance, and accuracy of the EYEMATE-SC in patients with primary open-angle glaucoma undergoing simultaneous nonpenetrating glaucoma surgery (NPGS).

DESIGN

Prospective, multicenter, open-label, single-arm, interventional clinical trial.

PARTICIPANTS

Twenty-four eyes of 24 patients with primary open-angle glaucoma who were due to undergo NPGS (canaloplasty or deep sclerectomy).

METHODS

An EYEMATE-SC sensor was implanted during NPGS. Goldmann applanation tonometry (GAT) measurements were compared with the sensors' IOP measurements at all postoperative visits through 12 months.

MAIN OUTCOME MEASURES

Device position and adverse events.

RESULTS

Fifteen eyes underwent canaloplasty, and 9 underwent deep sclerectomy. Successful implantation of the sensor was achieved in all eyes with no reported intraoperative difficulties. Through the 12-month follow-up, no device migration, dislocation, or serious device-related complications were recorded. A total of 536 EYEMATE-SC measurements were pairwise included in the IOP agreement analysis. The overall mean difference between GAT and EYEMATE-SC measurements was 0.8 mmHg (95% confidence interval [CI] of the limits of agreement [LoA], -5.1 to 6.7 mmHg). The agreement gradually improved, and from 3 months after surgery until the end of the follow-up, the mean difference was -0.2 mmHg (95% CI of LoA, -4.6 to 4.2 mmHg) over a total of 264 EYEMATE-SC measurements, and 100% of measurements were within ±5 mmHg of GAT.

CONCLUSIONS

The EYEMATE-SC sensor was safe and well tolerated through 12 months. Moreover, it allowed accurate, continuous IOP monitoring.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Outcomes of primary surgical treatment of medically recalcitrant post-keratoplasty glaucoma with transscleral cyclophotocoagulation

PURPOSE

To report the outcomes of slow-coagulation continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) in post-keratoplasty glaucoma refractory to medical therapy.

METHODS

Medical records of 47 patients (mean age of 70.7 ± 15.7 years and follow-up of 13.9 ± 7.1 months) were retrospectively enrolled. All patients had the diagnosis of secondary glaucoma after penetrating keratoplasty (PKP; n = 28) or Descemet's stripping automated endothelial keratoplasty (DSAEK; n = 19) with no previous history of incisional glaucoma or TSCPC surgeries. Study participants underwent slow-coagulation CW-TSCPC (1250-milliwatt power and 4-second duration).

RESULTS

A statically significant reduction of IOP from 31.8 ± 8.0 mmHg preoperatively to 16.9 ± 9.0 mmHg postoperatively was noted (p < 0.001). Similarly, the number of glaucoma medications decreased from 4.0 ± 1.0 to 2.7 ± 1.4 (p < 0.001). The overall success rates at 12 and 24 months were 68.1% and 66.0%, respectively, with no difference in success rates between post-PKP and post-DSAEK subgroups (p = 0.836). No significant changes in VA or central corneal thickness (CCT) were observed (p = 0.345 and 0.311, respectively). One (3.3%) patient had a graft rejection. The majority of the complications noted during this study were mild and transient.

CONCLUSIONS

Our study suggests that slow-coagulation TSCPC may be a safe and efficient surgical glaucoma treatment modality in patients with medically uncontrolled post-keratoplasty glaucoma.

Systematic Literature Review of Clinical, Economic, and Humanistic Outcomes Following Minimally Invasive Glaucoma Surgery or Selective Laser Trabeculoplasty for the Treatment of Open-Angle Glaucoma with or Without Cataract Extraction

Introduction

Selective laser trabeculoplasty (SLT) and minimally invasive glaucoma surgery (MIGS) are increasingly used options for mild-to-moderate open-angle glaucoma (OAG) care. While most MIGS devices are indicated for use in combination with cataract surgery only, with phacoemulsification playing a role in lowering IOP, newer technologies can also be used as standalone glaucoma surgery.

Methods

This systematic literature review (SLR) aimed to assess the clinical, economic, and humanistic outcomes of MIGS and SLT for the treatment of OAG and was conducted according to PRISMA guidelines. Studies that assessed MIGS or SLT in at least one treatment arm versus any other glaucoma treatment in adults with mild-to-moderate OAG were included. Clinical, humanistic (health-related quality of life [HRQoL] and patient burden), and economic data were extracted, and the methodological quality of included studies was evaluated.

Results

A total of 2720 articles were screened, and 81 publications were included. Fifty-eight reported clinical outcomes. The majority assessed iStent or iStent inject (n=41), followed by OMNI (n=9), gonioscopy-assisted transluminal trabeculotomy (GATT) or the Kahook Dual Blade (KDB) (n=7), Hydrus (n=6), SLT (n=5), Xen Gel Stent (n=2), PreserFlo (n=1), and iTrack (n=1). IOP reduction was observed across prospective studies, varying from -31% to -13.7% at month 6 and from -39% to -11.4% at year 1 versus baseline. Most adverse events were transient and non-serious. Limited humanistic and economic data were identified.

Conclusion

Given their established efficacy and safety, there is a rationale for wider use of MIGS in mild-to-moderate OAG. Of the MIGS devices, iStent and OMNI have the largest clinical evidence base supporting their sustained effectiveness.

Ocular P2 receptors and glaucoma

Adenosine triphosphate (ATP), an energy source currency in cells, is released or leaked to the extracellular space under both physiological and pathological conditions. Extracellular ATP functions as an intercellular signaling molecule through activation of purinergic P2 receptors. Ocular tissue and cells release ATP in response to physiological stimuli such as intraocular pressure (IOP), and P2 receptor activation regulates IOP elevation or reduction. Dysregulated purinergic signaling may cause abnormally elevated IOP, which is one of the major risk factors for glaucoma. Glaucoma, a leading cause of blindness worldwide, is characterized by progressive degeneration of optic nerves and retinal ganglion cells (RGCs), which are essential retinal neurons that transduce visual information to the brain. An elevation in IOP may stress RGCs and increase the risk for glaucoma pathogenesis. In the aqueous humor of human patients with glaucoma, the ATP level is significantly elevated. Such excess amount of ATP may directly cause RGC death via a specific subtype of P2 receptors. Dysregulated purinergic signaling may also trigger inflammation, oxidative stress, and excitotoxicity via activating non-neuronal cell types such as glial cells. In this review, we discussed the physiological roles of extracellular nucleotides in the ocular tissue and their potential role in the pathogenesis of glaucoma. This article is part of the Special Issue on 'Purinergic Signaling: 50 years'.

Goldmann and modified Goldmann tonometry measuring intraocular pressure changes in eyes which underwent myopic laser in situ Keratomileusis and photorefractive keratectomy

PURPOSE

Compare intraocular pressure (IOP) measured by a standard Goldmann applanation tonometer prism (IOPg) and a modified correcting applanation tonometer surface Goldmann prism (IOPc) before and after laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).

METHODS

Goldmann tonometry was analyzed in a retrospective, cross-sectional study, using both GAT and modified-GAT prisms pre-operatively and at the 3 month post-operative appointment on 120 eyes (64 patients) who received LASIK (n = 58) or PRK (n = 62). Demographics, central corneal thickness (CCT), manifest refraction and corneal curvature (CC) data was collected at each visit as well as surgical parameters, including maximum ablation depth.

RESULTS

Mean paired IOP following LASIK decreased by - 3.28 ± 3.2 mmHg measured by IOPg and - 1.93 ± 3.3 mmHg by IOPc (p ≤ 0.0001). Mean paired IOP following PRK reduced by - 1.92 ± 3.6 mmHg measured by IOPg and - 1.06 ± 3.6 mmHg by IOPc (p ≤ 0.0001). Increased LASIK ablation depth and post-procedural change in CCT trended toward a statistically significant reduction in IOPg (p = 0.07,p = 0.12), but not IOPc (p = 0.18,p = 0.32). PRK ablation depth was not associated with a reduction in IOPg or IOPc.

DISCUSSION

The modified Goldmann (IOPc) prism measured less of an IOP reduction following LASIK and PRK compared to the standard (IOPg) prism, and the IOP reduction with both prisms was associated with the degree of myopic correction.

WHAT IS ALREADY KNOWN AND THE RESIDUAL QUERY

Corneal refractive surgery generally demonstrates significant postoperative Goldmann IOP reductions. Presumably, this is due to corneal biomechanical changes for which a newer method of Goldmann IOP measurement may be able to compensate.

WHAT THIS STUDY ADDS

A modified, corneal conforming Goldmann prism demonstrates significantly less IOP reduction following myopic LASIK and PRK compared to the standard flat Goldmann prism.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

A newer, modified Goldmann prism may help detect glaucoma and OHT at an earlier stage in patients which have undergone LASIK or PRK. The findings corroborate predicted corneal biomechanical changes following the most common corneal refractive procedures.

Stress induced aging in mouse eye

Aging, a universal process that affects all cells in an organism, is a major risk factor for a group of neuropathies called glaucoma, where elevated intraocular pressure is one of the known stresses affecting the tissue. Our understanding of molecular impact of aging on response to stress in retina is very limited; therefore, we developed a new mouse model to approach this question experimentally. Here we show that susceptibility to response to stress increases with age and is primed on chromatin level. We demonstrate that ocular hypertension activates a stress response that is similar to natural aging and involves activation of inflammation and senescence. We show that multiple instances of pressure elevation cause aging of young retina as measured on transcriptional and DNA methylation level and are accompanied by local histone modification changes. Our data show that repeated stress accelerates appearance of aging features in tissues and suggest chromatin modifications as the key molecular components of aging. Lastly, our work further emphasizes the importance of early diagnosis and prevention as well as age-specific management of age-related diseases, including glaucoma.

Decreased outflow facility and Schlemm's canal defects in a mouse model of glaucoma

Previously we identified B6.EDA+/+ mice as a novel mouse model that presents with elevated IOP and trabecular meshwork damage. Here, we expand on our previous findings by measuring aqueous humor outflow facility and analyzing the integrity of the inner wall of Schlemm's canal. As expected, intraocular pressure (IOP) was increased, and outflow facility was decreased compared to C57BL/6J controls. B6.EDA+/+ mice had significantly increased expression of the adherens junction protein, VE-cadherin by the inner wall endothelium of Schlemm's canal. These data suggest that in addition to trabecular meshwork damage, there are changes in Schlemm's canal in B6.EDA+/+ mice that lead to aqueous outflow dysfunction and ocular hypertension.

Cannabidiol Loaded Topical Ophthalmic Nanoemulsion Lowers Intraocular Pressure in Normotensive Dutch-Belted Rabbits

Cannabidiol (CBD) is the major non-psychoactive and most widely studied of the cannabinoid constituents and has great therapeutic potential in a variety of diseases. However, contradictory reports in the literature with respect to CBD's effect on intraocular pressure (IOP) have raised concerns and halted research exploring its use in ocular therapeutics. Therefore, the current investigation aimed to further evaluate CBD's impact on the IOP in the rabbit model. CBD nanoemulsions, containing Carbopol^® 940 NF as a mucoadhesive agent (CBD-NEC), were prepared using hot-homogenization followed by probe sonication. The stability of the formulations post-moist-heat sterilization, in terms of physical and chemical characteristics, was studied for three different storage conditions. The effect of the formulation on the intraocular pressure (IOP) profile in normotensive Dutch Belted male rabbits was then examined. The lead CBD-NEC formulation (1% w/v CBD) exhibited a globule size of 259 ± 2.0 nm, 0.27 ± 0.01 PDI, and 23.2 ± 0.4 cP viscosity, and was physically and chemically stable for one month (last time point tested) at 4 °C, 25 °C, and 40 °C. CBD-NEC significantly lowered the IOP in the treated eyes for up to 360 min, with a peak drop in IOP of 4.5 mmHg observed at the 150 min time point, post-topical application. The IOP of the contralateral eye (untreated) was also observed to be lowered significantly, but the effect lasted up to the 180 min time point only. Overall, topically administered CBD, formulated in a mucoadhesive nanoemulsion formulation, reduced the IOP in the animal model studied. The results support further exploration of CBD as a therapeutic option for various inflammation-based ocular diseases.

The Association of Female Reproductive Factors with Glaucoma and Related Traits: A Systematic Review

TOPIC

This systematic review summarizes evidence for associations between female reproductive factors (age at menarche, parity, oral contraceptive [OC] use, age at menopause, and postmenopausal hormone [PMH] use) and intraocular pressure (IOP) or open-angle glaucoma (OAG).

CLINICAL RELEVANCE

Understanding the associations between female reproductive factors and glaucoma may shed light on the disease pathogenesis and aid clinical prediction and personalized treatment strategies. Importantly, some factors are modifiable, which may lead to new therapies.

METHODS

Two reviewers independently extracted articles in MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials databases to identify relevant studies. Eligibility criteria included studies with human subjects aged > 18 years; a measured outcome of either IOP or OAG; a cohort, case-control, cross-sectional, or randomized controlled trial design; a reported measure of association, such as the hazard ratio, relative risk, odds ratio, or mean difference, with an associated confidence interval; and a measured exposure of at least 1 of the following variables: age at menarche, parity, OC use, age at menopause, or PMH use.

RESULTS

We included a total of 27 studies. Substantial differences in study designs, exposure and treatment levels, treatment durations, and variable reporting precluded a meaningful quantitative synthesis of the identified studies. Overall, relatively consistent associations between PMH use and a lower IOP were identified. Estrogen-only PMH use may be associated with lower OAG risk, which may be modified by race. No significant associations were found with combined estrogen-and-progesterone PMH use. No strong associations between parity or age at menarche and glaucoma were found, but a younger age at menopause was associated with an increased glaucoma risk, and adverse associations were identified with a longer duration of OC use, though no overall association with OC use was found.

CONCLUSIONS

The association between PMH use and lower IOP or OAG risk is a potentially clinically relevant and modifiable risk factor and should be investigated further, although this needs to be interpreted in the context of a high risk of bias across included studies. Future research should examine associations with IOP specifically and how the relationship between genetic factors and OAG risks may be influenced by female reproductive factors.

Multipressure Dial Goggle Effects on Circumpapillary Structure and Microvasculature in Glaucoma Patients

PURPOSE

To evaluate the effects of pressure changes induced by a multipressure dial (MPD) on circumpapillary retinal nerve fiber layer (RNFL) and capillary density (CD) measurements in patients with glaucoma using OCT angiography (OCTA).

DESIGN

Prospective interventional study.

PARTICIPANTS

Twenty-four patients with primary open-angle glaucoma.

METHODS

One eye of each patient underwent negative pressure application with the MPD. The MPD alters intraocular pressure (IOP) relative to atmospheric pressure by generating a negative pressure vacuum within a goggle chamber that is placed over the eye. Each participant underwent serial high density OCTA imaging (AngioVue) of the optic nerve head at different negative pressure increments of -5 mmHg, starting from 0 mmHg, ending at -20 mmHg, and then returning to baseline. Images were acquired after 2 minutes of sustained negative pressure at each target pressure to allow for stabilization of the retinal structures and microvasculature. The RNFL thickness and CD measurements were automatically calculated using the native AngioVue software, and then exported for analysis.

MAIN OUTCOME MEASURES

The influence of different levels of negative pressure on circumpapillary RNFL thickness and CD measurements, assessed by a linear mixed-effects model with repeated measures.

RESULTS

The mean (± SD) age was 71.0 years (± 7.8 years), the baseline IOP was 17.5 mmHg (± 3.6 mmHg), and there was a mean 24-2 mean deviation of -2.80 dB (± 2.55 dB). Serial circumpapillary CD measurements showed a statistically significant dose-dependent increase from baseline, without negative pressure application, to the maximum negative pressure application of -20 mmHg (difference, 2.27%; P = 0.010). Capillary density measurements then decreased symmetrically when lowering the negative pressure to baseline. Circumpapillary CD measurements at target negative pressures of -10 mmHg, -15 mmHg, and -20 mmHg were significantly higher than the baseline measurements (all P values < 0.05). Circumpapillary RNFL thickness remained the same throughout different levels of negative pressure.

CONCLUSIONS

Circumpapillary CD measurements showed a dose-dependent increase with the induction of negative pressure, while RNFL thickness measurements remained unchanged.

Outcomes of ab-interno irrigating goniectomy with trabectome in primary and secondary glaucoma from a single center in India

Purpose

This study was done to report intermediate-term outcomes of irrigating goniectomy with trabectome (trabectome) surgery among different types of glaucoma eyes from a single center in India using a cross-sectional, longitudinal, observational study design.

Methods

Fifty-three patients (58 eyes) with glaucoma who underwent irrigating goniectomy with trabectome between January 2019 and February 2020 were included. Pre-operative data included age, gender, eye laterality, specific diagnosis, number of anti-glaucoma medications (AGMs), prior glaucoma surgeries, visual acuity, and intraocular pressure (IOP) on medical treatment. Post-operative data included IOP changes during the follow-up till 1-year, number of AGMs, any complications, or additional surgical intervention required. Success was defined as IOP ≤ 21 mmHg and ≥ 20% reduction of IOP from pre-operative IOP with no additional glaucoma surgery.

Results

The cohort included 58 eyes (male 53.4% and female 46.6%) ranging from 0.6 to 81 years of age. The average baseline IOP was 23.4 ± 10.2 mmHg and reduced significantly with surgery to 14.1 ± 5.3 mmHg at 1-year follow-up. The AGMs reduced from 2.4 ± 1.4 pre-surgery to 1.6 ± 1.4 at 1-year follow-up. Four eyes required additional glaucoma surgeries for IOP control. The success rate of trabectome with phacoemulsification (88%) was discernibly higher than with trabectome alone (67%). Intra-operatively, significant blood reflux was noticed in 27 eyes, of which only one required tamponading with a viscoelastic agent.

Conclusion

This study concludes that irrigating goniectomy with trabectome has good efficacy and safety in both pediatric and adult cases of glaucoma in terms of IOP control, reduction in AGMs, and low incidence of complications in the Indian population.

Finite element method for estimation of applanation force and to study the influence of intraocular pressure of eye on tonometry

PURPOSE

Discover the associations of force of applanation on the eye with the plunging depth of the cornea and quantify them. The results will be utilized as the feedback parameter in the new prototype development of eye care instruments as additional force may damage the internal structure of the eye or may result in erroneous output.

METHOD

A finite element-based eye model is designed utilizing the actual dimensions of the human eye. A standardized tonometer is designed and the simulation is carried out at predetermined deformation of the cornea to find the force of applanation on the cornea during tonometry. Adding on, the influence of IOP during tonometry is analyzed for a range of plunging depths of the cornea.

RESULTS

The graphical results inferred the linear relation between the force of applanation with the deformation of the cornea and the results are quantified. The resulting deformation and stress plot of FEM based simulation approach is analyzed and observations regarding deformations and stress are made.

CONCLUSION

The human eye is successfully developed and also computed force on the cornea during tonometry is validated. The inference drawn from the deformation plot and stress plot is that the junction of cornea-sclera along with cornea-tonometer periphery undergo maximum deformation and experiences the highest stress compared to other areas of the eye while during tonometry.

Prophylactic efficacy of intravenous paracetamol administration to reduce the incidence of post-operative ocular hypertension in dogs undergoing phacoemulsification: A pilot study

PURPOSE

To determine whether intravenous administration of paracetamol can prevent postoperative ocular hypertension (POH) in dogs following routine phacoemulsification.

METHODS

Diabetic and non-diabetic patients (total 54 dogs) undergoing unilateral or bilateral phacoemulsification were recruited to this placebo-controlled, prospective study. The control group received 1 ml/kg saline via intravenous infusion while the treatment group received 10 mg/kg paracetamol via intravenous infusion. Infusions were administered 30 min prior to surgery and repeated 12 h following initial administration. All patients received topical latanoprost at the conclusion of surgery. Intraocular pressure (IOP) was measured before premedication (baseline), and at 1 h, 3 h, 5 h and 18 h following extubation. POH was defined as an IOP above 25 mmHg (POH25). In addition, the number of patients with an IOP exceeding 20 mmHg was analyzed (POH20).

RESULTS

POH20 occurred in 33 of 54 animals (61.1%), including 19 of 25 animals (76.0%) in the control group and 14 of 29 animals (55.2%) in the treatment group. POH25 occurred in 23 of 44 animals (52.3%), including 13 of 25 animals (52.0%) in the control group and 10 of 29 animals (34.5%) in the treatment group. Paracetamol administration showed a significant positive effect on reducing the incidence of POH20 (p = .048), but not POH25 (p = .221).

CONCLUSIONS

When comparing groups, treatment with paracetamol showed a statistically significant reduction in the incidence of POH20, although no differences were observed in the incidence of POH25 between groups. Further studies are warranted to explore whether alternative drug regimes or routes of administration can provide enhanced efficacy in the prevention of POH25.

Symptom coaching and symptom validity tests: An analog study using the structured inventory of malingered symptomatology, Self-Report Symptom Inventory, and Inventory of Problems-29

In this pilot and exploratory study, we tested the robustness of three self-report symptom validity tests (SVTs) to symptom coaching for depression, with and without additional information available on the Internet. Specifically, we divided our sample (N = 193) so that each subject received either the Structured Inventory of Malingered Symptomatology (SIMS; n = 64), the Self-Report Symptom Inventory (SRSI; n = 66), or the Inventory of Problems-29 (IOP-29; n = 63). Within each of the three subgroups, approximately one third of participants were instructed to respond honestly (Genuine Condition, nSIMS = 21; nSRSI = 24; nIOP-29 = 26) and approximately two-thirds were instructed to feign depression. One half of the feigners were presented with a vignette to increase their compliance with instructions and were given information about symptoms of depression (Coached Feigning, nSIMS = 25; nSRSI = 18; nIOP-29 = 21), and the other half were given the same vignette and information about symptoms of depression, plus two Internet links to review before completing the test (Internet-Coached Feigning, nSIMS = 18; nSRSI = 24; nIOP-29 = 16). Overall, the results showed that the genuine conditions yielded the lowest total scores on all three measures, while the two feigning conditions did not significantly differ from each other. Looking at the detection rates for all feigning participants, all three measures showed satisfactory results, with IOP-29 performing slightly better than SIMS and SIMS performing slightly better than SRSI. Internet-Coached Feigners scored slightly lower on all three measures than feigners who were coached without the Internet links. Taken together, the results of this preliminary and exploratory study suggest that all three SVTs examined are sensitive to feigned depression even in the presence of symptom coaching, both with and without additional Internet-based information.

Impact of mucoadhesive agent inclusion on the intraocular pressure lowering profile of Δ9-tetrahydrocannabinol-valine-hemisuccinate loaded nanoemulsions in New Zealand white rabbits

The current study aimed to determine the effect of inclusion of a mucoadhesive agent on the intensity and duration of intraocular pressure (IOP) lowering activity of Δ⁹-tetrahydrocannabinol-valine-hemisuccinate (THC-VHS) loaded in a nanoemulsion (THC-VHS-NE) formulation. THC-VHS-NE formulation with Carbopol®940NF added as a mucoadhesive agent (THC-VHS-NEC) was prepared using hot-homogenization followed by probe sonication and characterized. A comparative evaluation of the IOP lowering activity of THC-VHS-NEC, THC-VHS-NE, THC-NEC, and commercial latanoprost ophthalmic solution, was undertaken in normotensive New Zealand white rabbits. The effect of pH, surfactant concentration, and autoclave process on the IOP lowering activity of THC-VHS-NEC was also studied. The formulation demonstrated desired viscosity, physicochemical properties, and autoclave process stability. The THC-VHS-NEC formulation showed a significant (p < 0.05) improvement in the duration of IOP lowering activity, compared to THC-NEC and THC-VHS-NE. Moreover, in this model, THC-VHS-NEC was more effective than commercially available latanoprost ophthalmic formulation, in terms of both duration and intensity of IOP lowering. A change in formulation pH, surfactant concentration, or sterilization process did not impact the IOP lowering activity of THC-VHS-NEC. Overall, inclusion of a mucoadhesive agent in THC-VHS-NE formulation, significantly increased the duration of activity, and could lead to a once- or twice- a day dosing regimen.

Anterior-segment optical coherence tomography of filtering blebs in the early postoperative period of ab externo SIBS microshunt implantation with mitomycin C: Morphological analysis and correlation with intraocular pressure reduction

PURPOSE

To analyse the morphological evolution of filtering blebs with anterior-segment OCT (AS-OCT) and its correlation with intraocular pressure after ab externo SIBS microshunt implantation with mitomycin C (MMC) during a 3-month follow-up period.

METHODS

Twenty-eight filtering blebs of 28 patients with open-angle glaucoma were measured horizontally and vertically in the sub-Tenon space with AS-OCT after ab externo SIBS microshunt implantation with MMC. The intraocular pressure (IOP) was monitored simultaneously at each visit. Maturation of and morphological changes in the blebs and correlations with the IOP were recorded.

RESULTS

The average median preoperative IOP of 20.7 (range, 12-30) mmHg decreased to 8.5 (range, 4-17), 8.9 (range, 5-17), 10.4 (range, 8-16) and 10.9 (range, 9-15) mmHg at 24 hr, 1 week, 1 month and 3 months, respectively (p < 0.001). A multiform morphology on AS-OCT prevailed at all time points, with a 3.5% rate of a uniform bleb morphology at the first week. The horizontal and vertical diameters of the blebs increased from baseline to the third month. The horizontal expansion (406 ± 127 μm on day 7, p = 0.04, 712 ± 211 μm on day 30, p = 0.02 and 952 ± 218 μm on day 90, p < 0.001) was greater than the vertical expansion (16 ± 18 μm, p = 0.3 on day 1, 63 ± 27 μm, p = 0.02 on day 30 and 137 ± 34 μm, p < 0.001 on day 90) without correlation with the IOP (r = -0.3, p = 0.2).

CONCLUSION

Anterior-segment OCT (AS-OCT) of the filtering blebs formed after ab externo SIBS microshunt implantation showed progressive horizontal and vertical expansion of the blebs in the sub-Tenon space, with a significant peak at the first month not significantly correlated with the decrease in the IOP.