Intraocular Pressure Response Research Articles

Continuous intraocular pressure variations following positional transitions in normal subjects and open angle glaucoma patients using a contact lens sensor system.

To evaluate the efficacy of a novel contact lens sensor system (CLS) in detecting continuous intraocular pressure (IOP) variations following positional transitions, and to explore these IOP variation patterns among normal subjects, untreated glaucoma patients, and untreated ocular hypertension (OHT) subjects. This prospective comparative study included 20 normal subjects, 14 high tension glaucoma (HTG) patients, 16 normal tension glaucoma (NTG) patients, and 14 OHT subjects. Participants wore the CLS for continuous IOP monitoring while undergoing sequential body position changes: from sitting to supine to a 10° head-down tilt (HDT), with each position maintained for ten minutes. Continuous IOP parameters, including mean, peak, and fluctuation (peak minus valley) in each position, as well as increment (peak minus starting value), interval (time to arrive peak), and velocity (increment divided by interval) after two position transitions, were compared among different positions and groups, respectively. Normal subjects, HTG and NTG patients exhibited higher CLS IOP mean and peak in supine/HDT positions compared to sitting (P < 0.05), but the mean or peak in HDT did not significantly differ from that in supine (P > 0.2). In OHT, all IOP parameters showed no significant difference among various positions (P > 0.1), except for velocity. Comparisons among groups revealed that during the transition from sitting to supine, HTG demonstrated higher IOP increment than other three groups and higher velocity than normal subjects (P < 0.05). NTG patients exhibited no significant differences in IOP increment, interval and velocity, compared to normal subjects (P > 0.05). The CLS proved effective in continuously recording IOP responses following positional changes in normal and glaucomatous eyes. Transitioning from sitting to supine resulted in increased IOP among normal subjects, HTG and NTG patients, but not in OHT. Compared to normal subjects, this IOP increase was more pronounced and rapid in HTG, but comparable in NTG. WHAT IS KNOWN : Positional transitions can induce IOP variations, which differ among normal subjects and glaucoma patients, and potentially relate to glaucomatous neuropathy. However, prior findings are constrained by the discontinuity of traditional tonometry. This study utilized a novel contact lens sensor system (CLS) to continuously monitor IOP during positional transitions in normal subjects and untreated glaucoma/OHT subjects. Continuous IOP outcomes revealed that normal subjects, HTG patients, and NTG patients exhibited an increase in IOP when transitioning from sitting to supine, whereas OHT did not. Compared to normal subjects, this increase in IOP was more pronounced and rapid in HTG patients, but similar in NTG.

The impact of different postures on acute intraocular pressure and accommodation responses during reading

IntroductionTo investigate the effects of different reading postures on intraocular pressure (IOP) and near-work-induced transient myopia (NITM) in children with myopia.MethodsSixty myopic children were instructed to read a book text placed at 33 cm for 30 min with two different reading postures: head bowed and head upright postures. The participants’ IOP and NITM were assessed using a rebound tonometer and an open-field autorefractor. The measurement of IOP was conducted prior to reading, during reading sessions (at 5, 10, 20, and 30-min intervals), and after a 5-min recovery period.ResultsFor the head bowed posture, the mean baseline IOP was 16.13 ± 2.47 mmHg. A significant rise in IOP was observed after 5 min of reading (17.17 ± 2.97 mmHg; +1.03 ± 2.29 mmHg; p = 0.014). Subsequent measurements revealed a further increase after 20 min (17.87 ± 2.90 mmHg; +1.73 ± 2.58 mmHg; p < 0.001), which continued to persist even after 30 min of reading (17.57 ± 3.46 mmHg; +1.43 ± 2.66 mmHg; p = 0.002). The IOP at different time points measured in the head upright posture did not show any significant difference in comparison to the baseline measurement (all p = 1.000). Compared to reading with the head upright, reading with the head bowed resulted in a greater increase in IOP at each time point (p < 0.05). Furthermore, the NITM was higher for reading with the head bowed than for reading with head upright at 30 min (-0.24 ± 0.53 D vs. -0.12 ± 0.47 D, p = 0.038).ConclusionReading in a head bowed position resulted in greater increases in IOP and NITM compared to reading in a head upright posture.

Manometric Intraocular Pressure Reduction with Negative Pressure Using Ocular Pressure Adjusting Pump Goggles

The Ocular Pressure Adjusting Pump is a novel, non-invasive and non-pharmacological intraocular pressure (IOP)-lowering device consisting of goggles attached to a negative pressure (NP) pump. This study aimed to determine the effect of negative pressure in Ocular Pressure Adjusting Pump goggles on IOP using continuous direct manometry. Prospective, single-arm, single center, basic physiological research trial. Adult patients undergoing cataract surgery. Direct manometry was performed via an anterior chamber cannula attached to an IOP sensor. This was placed just prior to each subject's previously scheduled cataract surgery. IOP was continuously monitored every 0.5 seconds through the following sequence of 30 seconds each: baseline IOP measurement, NP -10 mmHg, NP off, NP -20 mmHg, and NP off. IOP response to application of negative pressure. All seventeen subjects had a dose-dependent reduction in IOP, with a mean IOP decrease from 16.9 to 11.3 (33%) with -10 mmHg of NP and from 15.7 to 7.7 (51%) mmHg with -20 mmHg of NP. IOP returned to baseline for each cycle when NP was discontinued. There were no patients with increased IOP. Negative pressure with the Ocular Pressure Adjusting Pump results in a consistent dose-dependent reduction in IOP, with return to baseline IOP when NP is discontinued.

Predictors of intraocular pressure response and survival after phacoemulsification for glaucomatous eyes in the IRIS registry (Intelligent Research in Sight)

This retrospective cohort study describes the real-world incidence and maintenance of clinically meaningful intraocular pressure (IOP) reduction (“response”) following stand-alone phacoemulsification for 667,987 eyes with suspected or confirmed glaucoma in the IRIS Registry (Intelligent Research in Sight) from 1/1/2013–9/30/2019. Intraocular pressure responders had ≥ 20% IOP reduction in daily mean IOP from baseline on two consecutive postoperative visits. We declared failure if a responder no longer maintained ≥ 20% IOP reduction. The estimated IOP responder rate was 41.3% by Kaplan–Meier analysis. Multivariate analysis demonstrated relationships between IOP response and baseline IOP (hazard ratio (HR) (95% confidence interval)) 1.48 (1.48–1.49), per 3 mmHg, P < 0.0001), age (HR 1.14 (1.13–1.14), per 10 years, P < 0.0001), male sex (HR 1.13 (1.12–1.15), P < 0.0001), prostaglandin analogue (HR 0.88 (0.87–0.90), P < 0.0001), and Rho-kinase inhibitor use (HR 1.50 (1.32–1.70), P = 0.01). Fifty percent of IOP responders failed at a median time of 14.3 months. Multivariate analysis demonstrated relationships between failure and baseline IOP (HR 0.75 (0.75–0.76), per 3 mmHg, P < 0.0001), nitric oxide donating prostaglandin (HR 1.78 (1.46–2.18), P < 0.0001) and Rho-kinase inhibitor use (HR 1.73 (1.43–2.09), P < 0.0001). Clinicians may counsel glaucoma patients with risk factors on whether to anticipate an IOP response and its expected duration after stand-alone phacoemulsification.

"CYP3A4 Poor and Intermediate Metabolizers Have a Higher Rate of Steroid-Induced Intraocular Pressure Response".

Evaluate the relationship between CYP3A4 phenotype, the gene encoding the enzyme that metabolizes exogenous steroid, and the rate of steroid-induced intraocular pressure (IOP) response. Lymphocyte-derived DNA sequencing of CYP3A4 from 10073 patients was completed using the PGRN-Seq assay. Subjects with CYP3A4 intermediate metabolizer or slower phenotypes were identified and compared with controls matched by age, race and sex. All subjects had at least three eye exams with at least an exam while on topical/systemic/local steroid in any body location except the eye. Patients with pre-existing glaucoma or glaucoma suspect were excluded. Of the 10073 patients, there were 63 patients who had CYP3A4 poor or intermediate metabolizer phenotype. Of the 63 patients, 22 had documented steroid use. Fifty-nine percent (13/22) of patients with CYP3A4 poor/intermediate metabolizer had a steroid-induced IOP response of 3 mmHg or more, significantly higher compared to 23% (5/22) of matched controls (P=0.031). Although more poor /intermediate metabolizers were steroid responders, the average IOP elevation in steroid responders in both groups were similar (5.0 ± 2.5 mmHg in CYP3A4 poor/intermediate metabolizers compared to 4.1 ± 2.1mmHg in controls, P=0.327). Family history of glaucoma was similar in both groups (7/22 vs. 8/22, P=1.0). Reduced CYP3A4 phenotypes may help identify patients at a higher risk of steroid-induced IOP elevation. This retrospective study examined patients with sequenced CYP3A4, a gene encoding an enzyme that metabolizes exogenous steroids. When compared to normal metabolizers, CYP3A4 poor or intermediate metabolizers have a higher steroid-induced IOP response rate.

Intraocular Pressure Response to Perceived Stress in Juvenile-Onset Open Angle Glaucoma.

High perceived stress from academic pressure is associated with intraocular pressure (IOP) elevation and reduced fluctuation in juvenile-onset open angle glaucoma patients. Personalized stress assessment and relief strategies may serve as an adjunct therapy in glaucoma. To evaluate the effect of higher perceived stress, resulting from academic pressure, on IOP in juvenile-onset open angle glaucoma (JOAG) patients compared with healthy individuals. The study included 48 university students aged 18-27 years, comprising 24 JOAG patients on antiglaucoma eyedrops and 24 healthy controls. In an examiner-blind pretest-posttest design, participants' IOP was measured weekly using Goldmann tonometry during three follow-up visits at the beginning and end of the academic semester. Perceived Stress Scale (PSS) scores were also evaluated at these 2-time points to capture the contrast in perceived stress between periods of low and high academic pressure. The baseline PSS score at the semester's start was lower in both groups (14.1±1.9 in glaucoma vs. 13.5±2.4 in control) and significantly increased by the end of the semester (29.2±2.1 vs. 28.5±1.3; P <0.001), indicating increased perceived stress. Concurrently, IOP rose from 22.01±5.87 to 25.08±5.84mmHg in the glaucoma group and from 11.36±2.03 to 13.65±2.11mmHg in the control group. Factorial analysis revealed a significant interaction between stress and JOAG ( F(1,94) =15.94, P =0.001), partial η 2 =0.08, with stress having a greater increase on IOP in the glaucoma group (+3.10mmHg) compared with the control group (+2.23mmHg) ( t(94) =4.457, P <0.001). Higher perceived stress significantly increases IOP, especially in JOAG patients, suggesting personalized stress management as a potential adjunct therapy for patients.

Intraocular Pressure Response in the Untreated Contralateral Eye After Selective Laser Trabeculoplasty.

To examine the impact of selective laser trabeculoplasty (SLT) on intraocular pressure (IOP) in the untreated contralateral eye within 12 months after the procedure. A retrospective chart review was conducted on patients with primary open-angle, normal-tension, pigmentary, or pseudoexfoliation glaucoma who received 360-degree SLT at George Washington University. Exclusion criteria included prior or subsequent laser or glaucoma surgery within 12 months of SLT, other glaucoma types, or corticosteroid use during follow-up. Primary outcomes were IOP and medication reduction, and SLT success, defined as reducing IOP by ≥20% without additional IOP-lowering procedures or medications. Follow-up occurred at six weeks, six months, and 12 months. Demographic and clinical data were analyzed using ANOVA, paired t-tests, and chi-squared tests. A total of 125 patients were included, representing a range of backgrounds: African American (57.6%), Caucasian (31.2%), Asian (5.6%), and Hispanic/Latino (4%), and 1.6% did not report their background. Significant reductions in mean IOP and medication numbers were observed in the contralateral eye at six weeks and six months (p<0.05) but not at 12 months. The contralateral eye success rates were 24% at six weeks and six months and 20.8% at 12 months. The contralateral eye was more likely to achieve success if the ipsilateral eye was successful at six weeks (odds ratio (95% confidence interval): 5.05 (1.89-13.48)), six months (16.1 (4.56-57.17)), and 12 months (5.94 (2.07-17.04)) (p<0.001 for all). First-time SLT results in statistically significant IOP and medication reductions in the contralateral eye at six weeks and six months. The contralateral eye was 5.05-16.1 times more likely to achieve success if the ipsilateral eye was successful within 12 months.

Uveal effusion syndrome: a case report

BackgroundThis case report is applicable to the field of ophthalmology because there is a paucity of medical literature related to the clinical presentation, diagnosis, and management of uveal effusion syndrome. This is an urgent concern because there are severe complications associated with this disease, including non-rhegmatogenous retinal detachment, angle closure glaucoma, and possible blindness. This report will fill clinical knowledge gaps using a patient example.Case presentationA 68-year-old white male with multiple cardiovascular risk factors initially presented to the Eye Institute Urgent Care Clinic with new onset visual symptoms, including eye pain, eye lid swelling, redness, and tearing of his left eye. He had experienced a foreign body sensation in the left eye and bilateral floaters weeks prior to his presentation. The patient was examined, and vision was 20/30 in both eyes, and intraocular pressure was 46 in the right eye and 36 in the left eye. After initial assessment, including compression gonioscopy, intermittent angle closure glaucoma was suspected. He received oral diamox 500 mg, one drop of alphagan in both eyes, one drop of latanoprost in both eyes, one drop of dorzolamide in both eyes, and one drop of 2% pilocarpine in both eyes. There was only slight response in intraocular pressure. Owing to the bilateral angle closure, he underwent laser peripheral iridotomy to decrease intraocular pressure and open the angle that was found closed on gonioscopy. The patient was discharged on oral and topical glaucoma drops and scheduled for the glaucoma clinic. When he presented for follow-up in the glaucoma clinic, he was evaluated and noted to have bilateral narrow angles and intraocular pressure in the mid-twenties. A brightness scan (B-scan) was performed and was noted to have bilateral choroidal effusions, confirmed by Optos fundus photos. He was started on prednisone at 60 mg once per day (QD) with taper, continuation of oral and topical glaucoma medications, and a retina evaluation. Evaluation with a retina specialist showed resolving choroidal effusion in the left eye. He continued the prednisone taper as well as glaucoma drops as prescribed. Follow-up in the glaucoma clinic revealed a grade 3 open angle. He continued the prednisone taper, cosopt twice per day in both eyes, and discontinued brimonidine. The magnetic resonance imaging (MRI) that was performed showed results that were remarkable. No hemorrhage or mass was present. Follow-up with the retina specialist found that the choroidal effusions had resolved completely.ConclusionThis case report emphasizes the value in early detection, keen diagnostic evaluation, and cross-collaboration between multiple ophthalmology specialists to optimize healthcare outcomes for patients with uveal effusion syndrome.

Impact of atropine use for myopia control on intraocular pressure in children: A comprehensive review including postpupil dilation intraocular pressure changes.

Topical atropine has been widely used for controlling myopia progression in children, yet its long-term efficacy and safety, including potential intraocular pressure (IOP) elevation, are still being studied. The mydriasis and cyclopegia induced by atropine may reduce traction on the trabecular meshwork, together with pigment released into anterior chamber due to the friction between the iris and lens during pupil dilation, may obstruct and reduce the trabecular outflow. This review first explores postdilation IOP changes across different groups - healthy individuals, glaucoma patients, and children. The response to pupil dilation varies widely, with IOP potentially increasing or decreasing. Glaucoma patients, whether with open or closed-angle glaucoma, may experience more significant IOP rises postdilation. The second section examines IOP effects in children using topical atropine for myopia, where most of the 25 reviewed studies showed nonsignificant IOP changes, although slight increases were observed in a few. In addition, no alterations in the retinal nerve fiber layer thickness were found. However, the research on children's IOP under topical atropine is constrained by small sample sizes, cross-sectional studies, brief follow-ups, and often lacks control groups or pretreatment IOP measurements. Given the extended atropine use for myopia and the significant individual variation in IOP response, we recommend routine IOP monitoring for children receiving topical atropine.

The benefits of physical exercise on glaucoma management: Evidence‐based recommendations for eye care providers

The only proven method to treat glaucoma is the reduction and stabilization of intraocular pressure (IOP). A wide range of daily activities have shown to affect the IOP behaviour, and eye care specialists should be aware of their effects for the prevention and treatment of glaucoma. Indeed, the impact of physical activity on IOP has gained attention in the last years, and exercise prescription has emerged as a promising adjuvant strategy for IOP control in glaucoma patients. Previous studies have demonstrated that the IOP response to physical exercise may be dependent on numerous factors such as exercise type (e.g., endurance, resistance), exercise intensity, subjects´ fitness level, body position (e.g., supine vs. standing) and breathing pattern adopted during exercise, underlying medical conditions, concomitant mental effort or caffeine intake before exercise among others. This talk will summarize the available scientific evidence on the positive and negative effects of physical exercise on IOP, and provides practical recommendations for exercise prescription in glaucoma patients or those at risk. It will permit to better understand the potential benefits of exercise prescription as a coadjuvant strategy for the prevention and management of glaucoma, which would be of great relevance due to the important health, economic and social burdens associated with this condition.

To study dexmedetomidine’s effect on intraocular pressure after succinylcholine and endotracheal intubation

Background: One of the most important preconditions for any anesthetic operation is perioperative hemodynamic stability during laryngoscopy and intubation, which has been the subject of extensive research and documentation. Numerous approaches have been proposed to protect the patient from the sympathetic reaction, intraocular pressure (IOP) response, and catecholamine response during laryngoscopy and intubation. Aims and Objectives: To study the efficacy of two doses of intravenous dexmedetomidine premedication given as a single bolus dose over 10 min, 0.4 μg/kg and 0.6 μg/kg, 10 min before induction in preventing the rise of intraocular pressure following succinylcholine administration and endotracheal intubation. Materials and Methods: A retrospective randomized study was conducted. Ethical committee permission and signed informed consent were obtained from 60 eligible patients before the trial began. Results: Premedication with either 0.4 mcg/kg I.V. or 0.6 mcg/kg I.V. of dexmedetomidine diluted in normal saline at a 2 mcg/mL concentration administered over 10 min before induction resulted in significant obtundation of the rise in IOP associated with succinylcholine administration and intubation. Sympathetic response to laryngoscopy and intubation was also significantly diminished. The dose of 0.4 mcg/kg I.V. produced the best hemodynamic stability. Conclusion: Therefore, from the above research it can be concluded that, before succinylcholine delivery and intubation, dexmedetomidine 0.4 mcg/kg I.V. can be used as a premedication in situations where an increase in IOP could be hazardous.

A retinal imaging system for combined measurement of optic nerve head vascular pulsation and stimulated vasodilation in humans

Vascular pulsation at the optic nerve head (ONH) reflects vessel properties. Reduction in the stimulated retinal vasodilatory capacity has been reported in diabetes, but its relation with vascular pulsation is unknown. Here we report a new retinal imaging system for correlative assessment of ONH vascular pulsation and stimulated retinal vasodilation. Retinal reflectance images were acquired before and during light flicker stimulation to quantify arterial and venous vasodilation (DAR, DVR) in subjects with and without diabetic retinopathy (N = 25). ONH vascular pulsation amplitude and frequency (PA, PF), were quantified by curve fitting of periodic intensity waveforms acquired in retinal vasculature (RV) and ONH tissue (ONHT) regions. The relationships between pulsation metrics, heart rate (HR), intraocular pressure (IOP), and vasodilatory responses were evaluated. Pulsation metrics were not significantly different between regions (p ≥ 0.70). In RV, inter-image variabilities of PA and PF were 10% and 6%, whereas inter-observer variabilities were 7% and 2% respectively. In both regions, PF was correlated with HR (p ≤ 0.001). PA was associated with DAR in both regions (p ≤ 0.03), but only with DVR in RV (p ≤ 0.05). Overall, ONH vascular pulsation was associated with stimulated retinal vasodilation, suggesting diabetes may have concomitant effects on retinal vasculature compliance and neurovascular coupling.

Hypertonie cortisonique tardive sous implants de dexaméthasone : à propos de 20 cas

Steroid-induced ocular hypertension (OHT) occurs in approximately one third of cases after dexamethasone implant (DEXi) injection. Among these, more than one fifth occur after the third DEXi intravitreal injection (IVI). Our goal was to analyze the clinical profiles of these late responders. A real-life, retrospective, observational study was conducted to assess demographic characteristics and intraocular pressure (IOP) responses in late responders (IOP ≥ 21mmHg, n DEXi ≥ 4). The following parameters were analyzed: IOP 2months after IVI and number of glaucoma medications needed. The IOP response compared to baseline was defined as low (< +6mmHg), moderate (≤ +15mmHg) or high (> 15mmHg). Late steroid-induced OHT occurred in 20.8% of cases. Twenty eyes (18patients) were included. The mean duration of follow-up was 3.8±1.9years. They received a mean number of 9.5±4.2IVI. The first OHT peak, measured at 25.3±3.2mmHg (21-31), occurred after 6.8±2.3IVI. Approximately 65% of OHT spikes occurred between the fourth and sixth IVI; 35% occurred later. At maximum, 1.7±1.0glaucoma medications and 0.75±0.79SLT procedures were required to control the OHT, with no filtering surgery required. The ratio of "low," "moderate," and "high" responders was 5%, 85% and 10% respectively. Late steroid-induced OHT occurs after at least 3DEXi in one fifth of multi-injected patients, requiring long-term IOP monitoring. This case series identifies mostly moderate responder profiles, whose IOP rise often remains well-controlled with medical management or laser treatment (SLT).

Enhancement of ocular anti-glaucomic activity of agomelatine through fabrication of hyaluronic acid modified-elastosomes: formulation, statistical optimisation, in vitro characterisation, histopathological study, and in vivo assessment

Aim The aim of this manuscript was to fabricate agomelatine (AGM) loaded elastosomes to improve its corneal permeation and ocular bioavailability. AGM is a biopharmaceutical classification system (BCS) class II with low water solubility and high membrane permeability. It has a potent agonistic action on melatonin receptors, so it is used for glaucoma treatment. Methods Elastosomes were made using modified ethanol injection technique according to a 22 × 41 full factorial design. The chosen factors were: edge activators (EAs) type, surfactant percent (SAA %w/w), and cholesterol:surfactant ratio (CH:SAA ratio). The studied responses were encapsulation efficiency percent (EE%), mean diameter, polydispersity index (PDI), zeta potential (ZP), percentage of drug released after two hours (Q 2h%), and 24 hours (Q 24h%). Results The optimum formula with the desirability of 0.752 was composed of Brij98 as EA type, 15%w/w SAA%, and 1:1 CH:SAA ratio. It revealed EE% of 73.22%w/v and mean diameter, PDI, ZP, Q 2h%, and Q 24h% values of 484.25 nm, 0.31, −30.75 mV, 32.7%w/v, and 75.6%w/v, respectively. It demonstrated acceptable stability for three months and superior elasticity than its conventional liposome. The histopathological study ensured the tolerability of its ophthalmic application. Also, it was proven to be safe from the results of the pH and refractive index tests. The in vivo pharmacodynamic parameters of the optimum formula revealed dominance in a maximum % decrease in intraocular pressure (IOP), the area under the IOP response curve, and mean residence time with the value of 82.73%w/v, 820.69%h, and 13.98 h compared to that of the AGM solution (35.92%w/v, 181.30%h, and 7.52 h). Conclusions Elastosomes can be a promising option to improve AGM ocular bioavailability.

Intravitreal dexamethasone to manage post endothelial keratoplasty cystoid macular oedema refractory to topical therapy.

To describe the visual and clinical outcomes of patients with post endothelial keratoplasty (EK) cystoid macular oedema (CMO) refractory to topical treatment with intravitreal sustained-release dexamethasone implant (Ozurdex). 131 eyes from 111 patients undergoing solitary or combined EK (52 DSAEK (40.0%) and 79 DMEK (60.0%)) at Southend University Hospital between January 2020 and February 2022 with a minimum follow-up of 6 months were evaluated. Patients suspected of having CMO underwent spectral-domain macular optical coherence tomography (SD-OCT) Patients with diabetes were not included in this series. CMO was identified in 5.3% (n = 7) of cases, with 2 of these patients responding to topical corticosteroid treatment. The remaining 5 patients underwent intravitreal dexamethasone implant, with 1 patient requiring repeat implant due to CMO recurrence. All presented within 2 months postoperatively. 4 out of 5 eyes treated with intravitreal dexamethasone achieved a Snellen BCVA ≤6/9.5. 1 patient had an uncontrolled rise in intraocular pressure (IOP) despite maximal medical treatment requiring an urgent PreserFlo Ab-Externo MicroShunt. The use of intravitreal sustained-release dexamethasone implant in the management of post EK CMO refractory to topical therapy is effective and safe in most cases, but patients should be monitored and treated promptly for any secondary IOP response.

Intraocular Pressure Spikes Following iStent Inject and the Relationship to Aqueous Outflow in Open Angle Glaucoma.

Adding trabecular bypass surgery (TBS) to phacoemulsification creates unpredictable short-term intraocular pressure (IOP) control that may be undesirable for patients with advanced glaucoma. Aqueous outflow (AO) responses after TBS are complex and probably multifactorial. To assess IOP spikes in patients with open angle glaucoma up to 1 month after iStent inject and their relationship to AO patterns measured by hemoglobin video imaging (HVI). We studied IOP for 4 weeks after TBS with iStent inject in 105 consecutive eyes with open angle glaucoma (6 TBS only and 99 combined with phacoemulsification). The change in IOP after surgery at each time point was compared with baseline measurements and the prior postoperative visit. IOP-lowering medications were stopped on the day of surgery in all patients. A smaller pilot study of 20 eyes (TBS only = 6 and combined = 14) underwent concurrent HVI to observe and quantify perioperative AO. Aqueous column cross-sectional area (AqCA) of one nasal and one temporal aqueous vein was calculated at each time point, and qualitative observations were documented. An additional 5 eyes were studied after phacoemulsification only. Mean IOP for the entire cohort (preoperative 17.3 ± 5.6 mm Hg) was lowest the day after TBS (13.1 ± 5.0 mm Hg) and peaked at 1 week (17.2 ± 8.0 mm Hg), before stabilizing by 4 weeks (15.2 ± 5.2 mm Hg; P < 0.00001). The same IOP pattern was seen when separating the group into a larger cohort without HVI (respectively 15.9 ± 3.2 mm Hg, 12.8 ± 4.9 mm Hg, 16.4 ± 7.4 mm Hg, and 14.1 ± 4.1 mm Hg; N = 85, P < 0.00001) and the smaller HVI pilot study (respectively 21.4 ± 9.9 mm Hg, 14.2 ± 4.9 mm Hg, 20.2 ± 9.7 mm Hg, and 18.9 ± 7.6 mm Hg; N = 20, P < 0.001). More than 30% IOP elevation above baseline occurred in 13.3% of the entire cohort at 1 week after surgery. This increased to 46.7% when IOP was compared with 1 day after surgery. Inconsistent AqCA values and patterns of aqueous flow were demonstrated after TBS. AqCA after phacoemulsification alone was maintained or increased within 1 week in all 5 eyes. After iStent inject surgery in patients with open angle glaucoma, intraocular spikes were most commonly seen at 1 week. AO patterns were variable and additional studies are needed to understand the pathophysiology underlying IOP responses after this procedure.

Influence of the body positions adopted for resistance training on intraocular pressure: a comparison between the supine and seated positions

ObjectivesA variety of factors are known to mediate on the intraocular pressure (IOP) response to resistance training. However, the influence of the body position adopted during resistance training on IOP remain unknown. The objective of this study was to determine the IOP response to the bench press exercise at three levels of intensity when performed in supine and seated positions.MethodsTwenty-three physically active healthy young adults (10 men and 13 women) performed 6 sets of 10 repetitions against the 10-RM (repetition maximum) load during the bench press exercise against three levels of intensity (high intensity: 10-RM load; medium intensity: 50% of the 10-RM load; and control: no external load) and while adopting two different body positions (supine and seated). A rebound tonometer was employed to measure IOP in baseline conditions (after 60 s in the corresponding body position), after each of the 10 repetitions, and after 10 s of recovery.ResultsThe body position adopted during the execution of the bench press exercise significantly affected the changes in IOP (p < 0.001, ηp2 = 0.83), with the seated position providing lower increases in IOP levels compared to the supine position. There was an association between IOP and exercise intensity, with greater IOP values in the more physically demanding conditions (p < 0.001, ηp2 = 0.80).ConclusionsThe use of seated positions, instead of supine positions, for the execution of resistance training should be prioritized for maintaining more stable IOP levels. This set of findings incorporates novel insights into the mediating factors on the IOP response to resistance training. In future studies, the inclusion of glaucoma patients would allow to assess the generalizability of these findings.

Primary Posterior Continuous Circular Capsulorhexis without the Use of Ophthalmic Viscosurgical Device.

Performing primary posterior capsulorhexis (PPCCC) during cataract surgery is an effective prevention of secondary cataracts. It is important not to damage the anterior vitreous membrane to minimize the possible complications and adverse side effects of this step of the surgery. Most authors use a viscoelastic material to protect the anterior vitreous membrane, injected into the space between the posterior lens capsule and the vitreous membrane through a small hole in the posterior capsule. The creation of posterior capsulorhexis using 25G forceps under an implanted intraocular lens while continuously filling the anterior chamber with irrigation fluid from an irrigation cannula, without the use of a viscoelastic material is, in our opinion, a safe, fast and cheap technique of PPCCC. This technique could theoretically lead to a lower incidence of postoperative complications such as higher postoperative intraocular pressure or anterior segment inflammatory response.

Enhanced glaucomatous damage accompanied by glial response in a new multifactorial mouse model.

Glaucoma is a complex, multifactorial neurodegenerative disease, which can lead to blindness if left untreated. It seems that, among others, immune processes, elevated intraocular pressure (IOP), or a combination of these factors are responsible for glaucomatous damage. Here, we combined two glaucoma models to examine if a combination of risk factors (IOP and immune response) results in a more severe damage of retinal ganglion cells (RGCs) and the optic nerves as well as an additional glia activation. Six-week-old wildtype (WT+ONA) and βB1-Connective Tissue Growth Factor (CTGF) mice (CTGF+ONA) were immunized with 1 mg ONA (optic nerve antigen). A WT and a CTGF control group (CTGF) received sodium chloride instead. IOP was measured before and every two weeks after immunization. After six weeks, electroretinogram (ERG) measurements were performed. Then, retinae and optic nerves were processed for (immuno-) histology. Further, mRNA levels of corresponding genes in optic nerve and retina were analyzed via RT-qPCR. Six weeks after immunization, the IOP in CTGF and CTGF+ONA mice was increased. The optic nerve of CTGF+ONA animals displayed the most severe cell inflammation, demyelination, and macroglia activation. Fewer numbers of oligodendrocytes were only observed in WT+ONA optic nerves, while more apoptotic cells triggered by the extrinsic pathway could be revealed in all three glaucoma groups. The number of microglia/macrophages was not altered within the optic nerves of all groups. The loss of neuronal cells, especially RGCs was most pronounced in CTGF+ONA retinae in the central part and this was accompanied by an enhanced activation of microglia/macrophages. Also, Müller cell activation could be noted in CTGF and CTGF+ONA retinae. In this new model, an additive degeneration could be noted in optic nerves as well as in the number of RGCs. These results suggest a potential additive role of high IOP and immune factors in glaucoma development, which will aid for understanding this multifactorial disease more precisely in the future.

Vitreous metastasis from cutaneous melanoma: diagnosis and management

Purpose: To report the clinical findings, treatments, and outcomes in a series of patients with vitreous metastasis from cutaneous melanoma. Methods: This single-center, retrospective, interventional case series included patients with biopsy-confirmed vitreous metastasis from cutaneous melanoma diagnosed between 1997 and 2020. Standard 23- or 25-gauge pars plana vitrectomy was performed for diagnostic sampling. Sclerotomies were treated with double or triple freeze-thaw cryotherapy. Perioperative intravitreal injections of melphalan (32 µg/0.075 mL) were administered, when indicated. Visual acuity, intraocular pressure, and systemic and ocular treatment responses were reported. Results: Five eyes of five patients with unilateral vitreous metastasis from cutaneous melanoma were identified. The median age at diagnosis was 84 (range, 37-88) years. The median follow-up after ophthalmic diagnosis was 28 (8.5-36) months; one patient did not have a follow-up. The initial visual acuity ranged from 20/30 to hand motions. Baseline clinical findings included pigmented or non-pigmented cellular infiltration of the vitreous (5/5), anterior segment (4/5), and retina (3/5). Four patients had secondary glaucoma. Systemic therapy included checkpoint inhibitor immunotherapy (n=3, all with partial/complete response), systemic chemotherapy (n=2), surgical resection (n=3), and radiation (n=2). The median time from primary diagnosis to vitreous metastasis was 2 (2-15) years. One patient had an active systemic disease at the time of vitreous metastasis. The final visual acuity ranged from 20/40 to no light perception. Ophthalmic treatment included vitrectomy in all five patients, intravitreal administration of melphalan in three, and intravitreal administration of methotrexate in one. One patient required enucleation, and histopathology revealed extensive invasion by melanoma cells. Conclusions: Vitreous metastasis from cutaneous melanoma can present as a diffuse infiltration of pigmented or non-pigmented cells into the vitreous and may be misdiagnosed as uveitis. Diagnostic pars plana vitrectomy and periodic intravitreal chemotherapy may be indicated.