Retrobulbar tube shunt: anterior chamber to back of the eye (A2B) efficacy in glaucomatous eyes with uncontrolled IOP

PURPOSE

The purpose of this study is to examine the efficacy and safety of a commercial model of the retrobulbar shunt, anterior chamber to back of the eye (A2B), in lowering intraocular pressure (IOP) and medication requirements after the failure of all other IOP-lowering therapies, including trabeculectomy with antimetabolites and tube shunt procedures.

METHODS

This is a single-site, prospective, nonrandomized concept study. Patients with prior failed tube shunts, or moderate to severe glaucoma refractory to treatment, were included. All subjects underwent A2B shunt implantation. Each subject's IOP and number of medications were assessed from baseline at each time interval using paired t tests. Primary outcome measures were IOP and glaucoma medication use pre- and postoperatively. Complete success is defined as (1) IOP ≤ 21 mmHg; (2) IOP reduction from baseline of ≥ 20%; (3) no reoperation for glaucoma; (4) no loss of light perception vision; (5) no chronic hypotony defined as IOP ≤ 5 mmHg; and (6) no use of supplemental glaucoma medication. "Qualified success" required satisfaction of the same criteria as "complete success" but with the use of supplemental glaucoma medication at 6 months.

RESULTS

Nineteen eyes of 19 patients (mean age 39.5 ± 6.4) were followed for 6 months. The mean IOP (mmHg±SEM) at 6 months dropped from baseline of 35.3 ± 2.3 to 18.5 ± 1.1(- 16.8, - 47%; p < 0.0001). The mean number of glaucoma medications (±SEM) at 30, 90, and 180 days decreased from a baseline of 2.4 ± 0.3 to < 0.3 at each interval (p < 0.0002). The complete and qualified success rates at 6 months were 46.6% (7/15) and 66.6% (11/15), respectively. The mean number of prior incisional glaucoma surgeries was 3.2. The percent of patients that had previously failed sub-Tenon tube shunt surgeries was 79%.

CONCLUSIONS

The A2B shunt is an effective rescue therapy in patients that have failed other IOP-lowering procedures. By shunting aqueous humor into the retrobulbar space, IOP and number of glaucoma medications required were substantially reduced for the 6-month postoperative assessment interval. The intrinsic properties of the retrobulbar space may limit the risk of fibrosis, the principal cause of bleb failure.

Effect of surfactant concentration and sterilization process on intraocular pressure-lowering activity of Δ9-tetrahydrocannabinol-valine-hemisuccinate (NB1111) nanoemulsions

The use of Δ⁹-tetrahydrocannabinol (THC) and Δ⁹-tetrahydrocannabinol-valine-hemisuccinate (THC-VHS; NB1111) has recently been investigated in the management of intraocular pressure (IOP). The current study was undertaken to develop an optimized THC-VHS-loaded nanoemulsion formulation (NE; THC-VHS-NE) that could improve the drug load and duration of activity. THC-VHS-NE formulation was prepared by homogenization followed by ultrasonication. Sesame oil, Tween®80, and Poloxamer®188 were used as the oil, surfactant, and cosurfactant, respectively. Stability of the optimized THC-VHS-NE formulation was observed at 4 °C. The IOP lowering effect of the lead formulations, commercial timolol, and latanoprost ophthalmic solutions, as well as an emulsion in Tocrisolve™ (THC-VHS-TOC), was studied in New Zealand White rabbits following topical administration. The effect of surfactant concentration and sterilization process on IOP-lowering activity was also studied. THC-VHS-NE formulations (0.5, 1.0, and 2.0% w/v) showed dose dependent duration of action. The 1.0%w/v THC-VHS-NE formulation was selected for further evaluation because of its desirable physical and chemical characteristics. THC-VHS-NE formulation prepared with 2% w/v Tween®80 exhibited a higher drop in IOP than the 0.75 and 4.0% w/v of Tween®80 containing formulations. The IOP-lowering duration was, however, similar for the formulations with 0.75 and 2.0% Tween®80, while that with 4.0% Tween®80 was shorter. THC-VHS-NE formulation produced a greater drop in IOP (p < 0.05) and a longer duration of activity compared to THC-VHS-TOC, latanoprost, and timolol. The formulation could be sterilized by filtration without impacting product attributes. Overall, the optimized THC-VHS-NE formulation demonstrated a significantly better IOP reduction profile in the test model compared to the commercial ophthalmic solutions evaluated.

Increased episcleral venous pressure in a mouse model of circumlimbal suture induced ocular hypertension

PURPOSE

To investigate changes in aqueous humor dynamics during intraocular pressure (IOP) elevation induced by circumlimbal suture in mice.

METHODS

Ocular hypertension (OHT) was induced by applying a circumlimbal suture behind the limbus in male adult C57BL6/J mice. In the OHT group, the suture was left in place for an average of 8 weeks (n = 10, OHT group). In the sham control group the suture was cut at 2 days (n = 9, sham group) and in the naïve control group (n = 5) no suture was implanted. IOP was measured at baseline across 3 days, 1 h post-suture implantation, and at the chronic endpoint. Anterior segments were assessed using optical coherence tomography (OCT). Episcleral venous pressure (EVP), total outflow facility (C), uveoscleral outflow (Fu) and aqueous humor flow rate (Fin) were determined using a constant-flow infusion model.

RESULTS

All aqueous dynamic and chronic IOP outcome measures showed no difference between sham and naïve controls (p > 0.05) and thus these groups were combined into a single control group. IOP was elevated in OHT group compared with controls (p < 0.01). Chronic suture implantation did not change pupil size, anterior chamber depth or iridocorneal angles (p > 0.05). EVP was significantly higher in OHT eyes compared to control eyes (p < 0.01). There was no statistical difference in C, Fu and Fin between groups (p > 0.05). A significant linear correlation was found between IOP and EVP (R² = 0.35, p = 0.001).

CONCLUSIONS

Circumlimbal suture implantation in mouse eyes results in chronic IOP elevation without angle closure. Chronic IOP elevation is likely to reflect higher EVP.

Effect of Topical 1% Tetracaine Hydrochloride on Intraocular Pressure in Ophthalmologically Normal Horses; a Pilot Study

The aim of this study was to evaluate the effect of topical 1% tetracaine hydrochloride on the intraocular pressure (IOP) in ophthalmologically normal horses. Thirty eyes of 15 clinically normal horses were used for this study. The animals were randomly assigned to two groups (treatment and control). Prior to the instillation of 1% tetracaine or placebo, the baseline IOPs (T0) of each animal were recorded in both groups. Then one drop of tetracaine was instilled randomly into one eye of each horse in the treatment group (8 horses). In the control group (7 horses), one drop of artificial tear was instilled in one randomly selected eye. The measurements were repeated at 2 minutes (T2), 5 minutes (T5), 15 minutes (T15), and 30 minutes (T30) post instillation via a rebound tonometer. There was no significant difference in the treatment group (P = .3). The peak IOP measured at T2 returned to the baseline value at T30. No significant difference was found in the mean IOP values between the treatment and the control groups, or between the males and females on any of the occasions (P > .05). The Results of this study revealed a nonsignificant increase of the IOP 2 minutes post instillation of 1% tetracaine in horses.

Single transient intraocular pressure elevations cause prolonged retinal ganglion cell dysfunction and retinal capillary abnormalities in mice

Transient intraocular pressure (IOP) elevations are likely to occur in certain forms of glaucoma and after intravitreal injections to treat various retinal diseases. However, the impact of these transient IOP elevations on the physiology of individual retinal ganglion cells (RGCs) is unknown. In this report, we explore how transient IOP elevations in mice affect RGC physiology, RGC anatomy, and retinal arteriole and capillary structure. Transient IOP elevation was induced in 12-week old wild type C57BL6J mice by injecting sodium hyaluronate into the anterior chamber. IOP was measured immediately after the injection and again 1 and 7 days later. Average peak IOP after injection was ~50 mmHg and subsequent IOPs returned to normal. RGC physiology was assessed with a multielectrode array (MEA) by calculating a spike triggered average (STA) at the same time points. RGC counts and retinal vascular structure were assessed 14 days after injection with immunohistochemistry to label RGCs and blood vessels. Transient IOP elevation caused a marked reduction of scotopic STA presence and delayed center and surround STA peak times that did not recover. Transient IOP elevation also caused a reduced photopic receptive field size and spontaneous firing rate, both of which showed some recovery with time. Transient IOP elevation also induced vascular remodeling: the number of capillary branches was decreased within the superficial and intermediate vascular plexi. RGC counts, retinal arteriole diameter, and deep capillary plexus branching were unaffected. These previously unappreciated findings suggest that transient IOP elevation may cause unrecognized and potentially long-term pathology to RGCs and associated neurovascular units which should be accounted for in clinical practice.

Pedunculated Lipoma of the Caecum Causing Colocolic Intussusception in an Adult

INTRODUCTION

Colocolic intussusception in adults is uncommon and poses both a diagnostic and therapeutic dilemma. The association of an underlying malignancy necessitates a preoperative confirmation of diagnosis. The presenting features are variable. Hence contrast enhanced computed tomography of the abdomen is pivotal for diagnosis. An en bloc resection of the specimen in accordance with standard oncological principles is the mainstay of treatment.

CASE REPORT

A case of colocolic intussusception in an adult is presented to highlight the difficulties in preoperative diagnosis and in selecting the best surgical option for treatment.

CONCLUSION

Adult bowel intussusception is a diagnostic dilemma with preoperative diagnosis being the biggest challenge. CT scan of the abdomen is an excellent diagnostic modality with high diagnostic accuracy. Explorative laparotomy with en bloc resection is mainstay of treatment in adults.

Selective laser trabeculoplasty in patients with angle recession glaucoma: A small case series

PURPOSE

To describe the results of selective laser trabeculoplasty (SLT) in eyes with angle recession glaucoma (ARG). To our knowledge, this is the first report of SLT being used as treatment modality for angle recession glaucoma. Argon laser trabeculoplasty (ALT) was used for ARG but showed a little therapeutic effect.

OBSERVATIONS

Retrospective case series of 4 eyes of 4 patients with history of non-penetrating injury to the eye resulted in angle recession glaucoma. All eyes underwent SLT. Post-treatment, the best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of glaucoma medications, additional need for intervention, and complications were recorded. Success of treatment was defined as an IOP reduction of 20% or reduction in medications and maintaining target IOP without further intervention during follow up period of more than 3 months.Mean patient age was 44 years (SD = 9) and 2 out of 4 were females. SLT treatment resulted in decreased IOP from 21 to 12 mmHg in one patient and from 26 to 20 mmHg with reduced medication burden in another patient and reduced medication burden in the third patient who stopped glaucoma medication with no significant change in IOP (from 10 to 14 mmHg) at last follow up visit at 45 months. Two SLT sessions failed in one patient who underwent tube surgery.In the 3 patients with successful treatment, IOP remained controlled for the duration of follow up ranging from 4 to 45 months.

CONCLUSIONS AND IMPORTANCE

Predicting IOP outcomes after SLT is difficult in patients with ARG. Success was noted early in the post-treatment period and was maintained for years. Repeating SLT in a case of early failure didn't change the result and is not recommended. A larger study is required to confirm the safety and effectiveness of SLT for ARG.

Effects of Consumption of Alcohol on Intraocular Pressure: Korea National Health and Nutrition Examination Survey 2010 to 2011

This study researched the association between alcohol consumption, intraocular pressure (IOP), and risk of open-angle glaucoma (OAG) using nationwide population-based cross-sectional data from the Korean population based survey. Information on alcohol intake was obtained by questionnaire and comprehensive ophthalmic examinations were performed. Among a total of 6057 participants, the prevalence of OAG was 4.4% (6.0% for men and 3.0% for women). Multivariate adjusted models showed that alcohol consumption showed significant relationship with changes in IOP. In sex-stratified analyses, alcohol consumption more than 2 times per week was associated with increased IOP in men without OAG, while in women with OAG drinking alcohol more than 4 times per week was associated with increased IOP. This study showed significant differences between men and women without glaucoma who consumed alcohol more than four times per week (p-value: 0.03). Our results suggest that alcohol consumption is associated with risk of elevated IOP depending on sex and presence of glaucoma in Koreans. Therefore, patients who need to control IOP should consider the effects of alcohol consumption.

Improved Efficacy of Topical Latanoprost 0.005% Demonstrated by Corneal Biomechanical Correcting Modified Goldmann Prism

Purpose

To evaluate intraocular pressure (IOP) reduction measured by a Goldmann applanation tonometer (GAT) prism and a modified surface Goldmann (CATS) prism with the institution of a topical prostaglandin analog (PGA) or alternatively a topical beta blocker.

Design

Prospective, open-label, randomized, controlled, and reference device comparison.

Methods

Thirty-six (36) treatment naïve glaucoma patients (72 eyes) were randomized equally to treatment with latanoprost 0.005% or timolol maleate 0.5%. Each patient underwent IOP measurement with standard GAT and CATS prisms before and at 1, 3, and 6 months of treatment. Central corneal thickness (CCT) and corneal hysteresis (CH) were also measured. Medication response was defined as a 20% reduction in IOP from baseline.

Results

The CATS prism demonstrated the IOP reduction with topical latanoprost at a mean of 1.9 mmHg lower than the IOP measured with GAT (p=0.01). The CATS and GAT prisms detected no difference in IOP reduction with timolol (p=0.23). The number of latanoprost treatment non-responders was reduced from 36.1% measured with GAT to 13.8% when measured with the CATS prism (p=0.005). Timolol indicated no difference in the treatment non-response rate at 22.2% (p=0.999). CH increased significantly with latanoprost treatment by an average of 0.55 mmHg (p=0.014) and remained unchanged with timolol at −0.014 mmHg (p=0.68).

Discussion

IOP reduction and responder rates were increased when measured with a CATS prism in patients using latanoprost and not with timolol use. Latanoprost-induced alterations in corneal biomechanics may dampen the actual IOP reduction measured with a standard GAT prism.

Clinical Trial Registration

ClinicalTrials.gov NCT04178863.

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Comparison of two eyelid speculums and their effect on intraocular pressure in clinically normal cats

OBJECTIVES

The present study was undertaken to determine the possible effects of the placement two different types of eyelid speculum on intraocular pressure (IOP) measurement in clinically normal cats.

METHODS

Thirty healthy cats were divided randomly into two groups of 15, group B (Barraquer wire speculum) and group W (Williams eye speculum). All cats were sedated with intramuscular medetomidine (Dorbene vet; 100 μg/kg) then placed in right lateral recumbency, and IOP was recorded in the left eye using a Tono-Pen Vet tonometer without and with an eyelid speculum in place in both groups.

RESULTS

The without-speculum IOPs for cats in group B and group W were 13.8 ± 3.0 mmHg and 13.2 ± 3.6 mmHg, respectively, and did not differ significantly. A significant increase in IOP (19.8 ± 3.7 mmHg) was observed in group W in with-speculum measurements in comparison to the without-speculum values (P <0.001).There was no significant difference between with- and without-speculum IOP values (13.8 ± 2.7 mmHg) in group B (P = 1.0).

CONCLUSIONS AND RELEVANCE

The Barraquer wire speculum has no effect on IOP compared with the Williams eye speculum in normal cats, and may be an appropriate choice in cats for intraocular surgeries that cannot tolerate acute increases in IOP.

Short-Term and Long-Term Variability of Intraocular Pressure Measured with an Intraocular Telemetry Sensor in Patients with Glaucoma

PURPOSE

To evaluate the short-term and long-term variability of intraocular pressure (IOP) in eyes with primary open-angle glaucoma.

DESIGN

Prospective study.

PARTICIPANTS

Twenty-two patients previously implanted with a sulcus-based IOP sensor (EyeMate, Implandata GmbH, Germany).

METHODS

Twenty-two patients previously implanted with the EyeMate were requested to obtain at least 4 IOP measurements daily. Data were grouped according to the eye and the medication so that an eye treated with a particular medication was considered as one group, and the same eye treated with a different medication during the observation period was considered as a different group. A day was divided into 7 periods: night, midnight to 5:59 am; early, 6 am to 7:59 am; morning, 8 am to 10:59 am; noon, 11 am to 1:59 pm; afternoon, 2 pm to 5:59 pm; evening, 6 pm to 8:59 pm; and late, 9 pm to 11:59 pm. Short-term variability during a particular period was defined as the variability in IOP measurements obtained during that period on different days within 3 months of each other. Long-term variability was defined as the variability in IOP measurements obtained during a particular period on different days over a period of 1 year or more. Variability was assessed using intraclass correlation coefficients (ICCs).

RESULTS

The mean age of study participants was 67.8 ± 6.8 years and 36.4% were women. The mean follow-up duration of patients was 19.2 ± 21.3 months (median, 9 months; range, 1-58 months). Overall, 92 860 IOP measurements over 15 811 measurement days were obtained and analyzed during the study period. The number of measurements obtained from each eye ranged from 1 daily to 277 daily. Intraclass correlation coefficients for short-term variability among the 7 periods during the day ranged from 0.52 (morning) to 0.66 (early). Long-term ICCs ranged from 0.29 (night) to 0.51 (late).

CONCLUSIONS

Continual IOP monitoring showed that IOP has moderate short-term and high long-term variability in glaucoma patients. These findings demonstrate that single IOP measurements do not characterize day-to-day variations in IOP. Moreover, they show the importance of continual IOP monitoring in glaucoma patients.

An In Vitro Bovine Cellular Model for Human Schlemm's Canal Endothelial Cells and Their Response to TGFβ Treatment

Purpose

Due to the limited availability of primary human Schlemm's canal (SC) endothelial cells, we aimed to develop an in vitro cellular model using the angular aqueous plexus (AAP) cells from bovine eyes.

Methods

We harvested a mixture of cells from the trabecular meshwork region including AAP loops from multiple donors, followed by puromycin treatment and immunostaining of Von Willebrand factor and vascular endothelial (VE)-cadherin to confirm identity. Previously identified differentially expressed genes in glaucomatous SC cells were examined in non-glaucomatous SC cells (n = 3) under 0% or 15% equibiaxial strain for 24 hours using droplet digital polymerase chain reaction (ddPCR) and analyzed using the Ingenuity Pathway Analysis (IPA) software application to identify upstream regulators. To compare the cellular responses to candidate regulators of these mechanoresponsive genes, AAP and human SC cells (n = 3) were treated with 5 or 10 ng/mL transforming growth factor beta-2 (TGFβ2) for 24 or 48 hours, followed with expression profiling using real-time PCR or ddPCR.

Results

We found that the isolated AAP cells displayed uniform cobblestone-like morphology and positive expression of two endothelial markers. In stretched SC cells, nine glaucoma-related genes were upregulated, and IPA implicated TGFβ as a potential upstream regulator. The effects of TGFβ2 treatment were similar for both AAP and SC cells in a dose- and time-dependent manner, activating TGFBR1 and SMAD2, inhibiting BMP4, and altering expression of three glaucoma-related genes (DCN,EZR, and CYP1B1).

Conclusions

Bovine AAP cells may serve as an alternative cellular model of human SC cells.

Translational Relevance

These AAP cells may be used to study the functional pathways related to the outflow facility.

Intensive Outpatient Treatment (IOP) of Behavioral Health (BH) Problems: Engagement Factors Predicting Subsequent Service Utilization

The purpose of the study is to 1) better understand patterns of utilization of Intensive Outpatient Treatment (IOP) Programs and Services in the State of Connecticut by adult Medicaid recipients experiencing a serious mental illness, substance use disorder, or co-occurring disorders; and 2) to determine the relationship between the duration of an IOP episode and connection to care rates for higher (i.e., rehospitalization) or lower levels of care following discharge. We hypothesized that the duration of an IOP episode would impact positively in reducing the use of higher levels of care while increasing the use of lower levels of care. In order to examine the frequency and duration of use of Intensive Outpatient (IOP) services by the CT Medicaid population, a two-year timeframe was selected: July 1, 2012 to June 30, 2014. A survival analysis was conducted to assess the risk of readmission to an IOP within 180 days based on demographic and utilization factors including, Age (in years on date of discharge), Race and Ethnicity, Gender, Homeless Status (at least one day in CY 2013), and Engagement Group (Intent to Treat, Early Termination, Minimally Adequate Dosage, & Target or More). To better understand the patterns of utilization associated with Adult IOP services, the average length of stay, number of treatment days, and average number of treatment days per week were explored. The number of unique individuals who were part of this analysis is 11,473, of which 2050 were mental health IOP utilizers (18%), 4598 were co-occurring IOP utilizers (40%), and 4825 (42%) were substance use IOP utilizers. For the total population, the average length of stay (ALOS) in days was 42 and the average number of treatment days attended per week was 2.5, for an average of 15 treatment days per episode of care. Among the IOP Cohorts, the Mental Health Cohort had the longest ALOS at 44.15 days, an average of 2.34 days of service per week, for an average of 14.76 days of IOP service per episode of care. The Substance Use Cohort had the shortest ALOS at 41.33 days, but had the highest intensity of services per week at 2.71 for an average of 16 days of service per episode of care. The Co-Occurring Cohort presented an ALOS of 41.74 days, an average of 2.32 services per week and an average of 13.83 sessions per episode. Overall there is evidence supporting an association between the number of days of care and protection from hospitalization, up to a certain number of days of care or number of days in IOP. Above the Minimally Adequate Dosage, the IOP protection factor seems to reach a plateau. This means that after 16 days of care, the chances of hospitalization remain the same regardless of the additional days provided.

Does Bariatric Surgery Affect Intraocular Pressure?

PURPOSE

The effect of body mass index (BMI) reduction following bariatric surgery on intraocular pressure (IOP) is not well established. We evaluated association between BMI reduction and IOP measurements and other ocular and metabolic parameters 1 year after bariatric surgery.

MATERIALS AND METHODS

A retrospective study with over 1-year follow-up on patients who underwent weight reduction bariatric surgery between January 2016 and December 2016 at Wolfson Medical Center, Israel. Patient data was extracted from outpatient's bariatric and ocular clinic records. Metabolic, ocular, and clinical parameters were assessed including BMI changes, IOP, central corneal and retinal nerve fiber layer thickness, optical coherence tomography, and biometry results.

RESULTS

Of 22 bariatric surgery patients, 15 underwent laparoscopic sleeve gastrectomy (LSG) and 7 laparoscopic mini gastric bypass (MGB). All were followed up for over 1 year after surgery. Average BMI decreased from 41.9 ± 7.3 to 25.5 ± 5.7 kg/m² at 1-year follow-up (p < 0.001). Mean IOP decreased significantly by 21% after 1 year (p < 0.001). Decrease in IOP 1 year after surgery was correlated with decrease in IOP at 3-month follow-up (r = 0.677, p = 0.001), preoperative IOP (r = 0.837, p < 0.001), and corneal thickness (r = 0.589, p = 0.006), with no correlation between reduction in IOP and baseline weight, BMI, or the reduction in either (p > 0.05). Central corneal thickness and retinal nerve fiber layer thickness were also significantly decreased (p = 0.038) and (p = 0.018), respectively.

CONCLUSION

BMI reduction achieved by bariatric surgery was associated with significant and continued decline in IOP beyond 1 year after surgery. Clinical implications highlight the importance of considering bariatric surgery in patients with ocular hypertension.

The effect of body position on intraocular pressure in anesthetized horses

OBJECTIVE

To evaluate the effect of four recumbent body positions on intraocular pressure (IOP) in anesthetized normal horses.

ANIMALS STUDIED

Ten nonglaucomatous adult horses.

PROCEDURES

Intraocular pressure was measured with a rebound tonometer in both eyes of standing sedated horses (baseline), then under general anesthesia during four randomized recumbent body positions, including Trendelenburg (Tr; 15-degree head down), reverse Trendelenburg (RTr; 15-degree head up), dorsal, and lateral; only the superior eye was measured in lateral positions. The mean of 3 IOP readings was taken at each position, allowing a minimum of 2 minutes of acclimatization after each position change before obtaining measurements. Repeated Measures Analysis with Newman-Keuls Multiple Comparison Post hoc was used to compare IOPs in different positions, and linear regression was used to compare IOP with age and weight cofactors.

RESULTS

When compared to baseline, the greatest change in IOP occurred in Tr (increase of 25.63 ± 8.12 mm Hg). When comparing all recumbent positions to baseline, IOP significantly increased in 3 of 4 body positions (P < .001), with no significant difference identified between RTr and baseline. When comparing all body positions to each other, the greatest IOP difference occurred between the Tr and the RTr positions (increase of 26.95 ± 5.41 mm Hg). Age and weight were not correlated with IOP in any position.

CONCLUSIONS

Recumbent body position significantly increases IOP in normal eyes of horses under injectable anesthesia.

Highly Transparent and Sensitive Graphene Sensors for Continuous and Non-invasive Intraocular Pressure Monitoring

Intraocular pressure (IOP) is the prime indicator for the diagnosis and treatment of glaucoma. IOP has circadian rhythm changes and is dependent on body gestures; therefore, a single measurement in the clinic can be misleading for diagnosis. Herein, few-layer graphene is utilized to develop non-invasive sensors with high transparency, sensitivity, linearity, and biocompatibility for 24 h continuous IOP monitoring. The graphene Wheatstone bridge consisting of two strain gauges and two compensating resistors is designed to improve the sensitivity and accuracy of IOP measurement. Testing results on a silicone eyeball indicate that the output voltage of the sensor is proportional to the IOP fluctuation. Under the various ranges and speeds of IOP fluctuation, the sensor exhibits excellent performance of dynamic cycles and step responses with an average sensitivity of 150 μV/mmHg. With the linear relationship, the average relative error between the calibrated IOP and the standard pressure is maintained at about 5%. More than 100 cycles and interval time measurements illustrate that the sensor possesses significant stability, durability, and reliability. Furthermore, a wireless system is designed for the sensor to realize IOP monitoring using a mobile phone. This sensor, with the average transparency of 85% and its ease of fabrication, as well as its portability for continuous IOP monitoring, brings new promise to the diagnosis and treatment of glaucoma.

A One-Year Follow-Up of Two Ahmed Glaucoma Valve Models (S2 and FP7) for Refractory Glaucoma: A Prospective Randomized Trial

Aim

To compare a range of clinical outcome variables (intraocular pressure, glaucoma medications, visual acuity, and complications) between two Ahmed glaucoma valve (AGV) models (S2 and FP7).

Methods

This was a prospective and randomized clinical trial. Fifty-six patients with refractory glaucoma were randomly assigned to be implanted with either a polypropylene (S2) or silicone (FP7) Ahmed glaucoma valve. The primary outcome measure was a surgical success, defined as an IOP ≤ 16 mm Hg (without medication), and guarded success, defined as a controlled IOP ≤ 16 mmHg (with medication). Failure was defined as when the IOP lay outside of the successful range on two consecutive visits (>16 mmHg, despite medication).

Results

Mean follow-up period was 398.42 ± 12.34 days (range, 380–420 days) for the S2 group and 401.75 ± 9.78 days (range, 385–420 days) for the FP7 group; these values were not significantly different (P = 0.27). After 12 months of follow-up, the baseline IOP (45.42 mmHg) fell significantly to 16.14 mmHg in the S2 group (p < 0.000); there was also a significant reduction in IOP in the FP7 group (from 44.17 mmHg to 15.18 mmHg in FP7 group, p < 0.000). At the last follow-up examination, the mean IOP in the S2 group was 16.14 ± 3.18 mmHg, while that of the FP7 group was 15.18 ± 2.75 mmHg; there was no significant difference between the two groups with this respect (p = 0.23). The mean number of medications used by patients in the S2 and FP7 groups was 2.92 ± 1.27 and 2.75 ± 1.43, respectively; there was no significant difference between the two groups with this respect (p = 0.32). There was no significant difference between the FP7 and S2 groups with regard to their relative success rate (17.89% [5/28] versus 10.7% [3/28], respectively; p = 0.38).

Conclusion

Our data show that the S2 and FP7 models of AGV were both effective in lowering IOP and reducing the need for glaucoma medications. Although these two AGV models had similar dimensions, they were constructed from different materials. However, there were no significant clinical differences between the S2 and FP7 AGV groups after 12 months of follow-up. Furthermore, our data indicate that bleb encapsulation was the primary factor responsible for failure rate and the need for glaucoma medication in both the S2 and FP7 groups. Our analysis further indicates that the S2 and FP7 Ahmed valves are associated with a high risk of failure when considered as a first-line therapy for cases experiencing trabeculectomy.

Clinical Trial Registration

NCT04214847.

Application of Cell Impedance as a Screening Tool to Discover Modulators of Intraocular Pressure

Purpose: To identify new targets and compounds involved in mediating cellular contractility or relaxation in trabecular meshwork (TM) cells and test their efficacy in an ex vivo model measuring outflow facility. Methods: A low-molecular weight compound library composed of 3,957 compounds was screened for cytoskeletal changes using the Acea xCelligence impedance platform in immortalized human NTM5 TM cells. Hits were confirmed by 8-point concentration response and were subsequently evaluated for impedance changes in 2 primary human TM strains, as well as cross-reactivity in bovine primary cells. A recently described bovine whole eye perfusion system was used to evaluate effects of compounds on aqueous outflow facility. Results: The primary screen conducted was robust, with Z' values >0.5. Fifty-two compounds were identified in the primary screen and confirmed to have concentration-dependent effects on impedance in NTM5 cells. Of these, 9 compounds representing distinct drug classes were confirmed to modulate impedance in both human primary TM cells and bovine cells. One of these compounds, wortmannin, an inhibitor of phosphoinositide 3-kinase, increased outflow facility by 11%. Conclusions: A robust phenotypic assay was developed that enabled identification of contractility modulators in immortalized TM cells. The screening hits were translatable to primary TM cells and modulated outflow facility in an ex vivo perfusion assay.

Inonotus obliquus polysaccharide ameliorates impaired reproductive function caused by Toxoplasma gondii infection in male mice via regulating Nrf2-PI3K/AKT pathway

This study was carried out to investigate the effects of Inonotus obliquus polysaccharide (IOP) on impaired reproductive function and its mechanisms in Toxoplasma gondii (T. gondii)-infected male mice. Results showed that IOP significantly improved the spermatogenic capacity and ameliorated pathological damage of testis, increased serum testosterone (T), luteinizing hormone (LH) and follicular-stimulating hormone (FSH) levels in T. gondii-infected male mice. IOP effectively up-regulated testicular steroidogenic acute regulatory protein (StAR), P450scc and 17β-HSD expressions. IOP also significantly decreased the levels of malondialdehyde (MDA) and nitric oxide (NO), but increased the activities of antioxidant enzyme superoxide dismutase (SOD) and glutathione (GSH). Furthermore, IOP up-regulated the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NADPH quinoneoxidoreductase-1 (NQO-1), and suppressed the apoptosis of testicular cells by decreasing Bcl-2 associated x protein (Bax) and cleaved caspase-3 expressions. IOP further enhanced testicular phosphatidylinositol 3-kinase (PI3K), phospho-protein kinase B (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) expression levels. It demonstrates the beneficial effects of IOP on impaired reproductive function in T. gondii-infected male mice due to its anti-oxidative stress and anti-apoptosis via regulating Nrf2-PI3K/AKT signaling pathway.

Can a contact lens sensor predict the success of trabectome surgery?

PURPOSE

We examined whether a contact lens sensor (CLS) is useful for the postoperative evaluation of trabectome surgery. We investigated the correlations between the outcomes of trabectome surgery and the output of a CLS.

METHODS

We examined 24 consecutive eyes of patients with pseudo-exfoliation glaucoma. In each eye, the intraocular pressure (IOP) fluctuations over 24 h were measured with the SENSIMED Triggerfish CLS before and at 3 months after the trabectome surgery. We divided the patients into success (n = 12 eyes) and failure (n = 12 eyes) groups; success was defined as a postoperative IOP level ≤ 21 mmHg plus an IOP reduction ≥ 20% relative to the preoperative IOP value with or without anti-glaucoma medications. We investigated CLS parameters that correlate with surgical outcomes by performing a Cox hazard regression analysis. We determined the maximum value, minimum value, and range of IOP fluctuation as CLS parameters.

RESULTS

The mean follow-up period was 38.0 ± 3.0 months. The success rate was 50%. The postoperative range of IOP fluctuation during the nocturnal period with the CLS was significantly correlated with the surgical results (p = 0.024).

CONCLUSIONS

A smaller range of IOP fluctuation was significantly correlated with better surgical outcomes. We were able to predict the surgical success after trabectome surgery at 3 months using the CLS. Thus, CLS results could be a new surgical evaluation parameter.

Two-year outcome of Trabeculo-Canalectomy for Chinese Glaucoma Patients

To evaluate the efficacy of trabeculo-canalectomy in treating glaucoma patients, a retrospective investigation of 53 glaucoma patients (53 eyes) who underwent trabeculo-canalectomy was conducted at the First Affiliated Hospital of Nanjing Medical University, China, from April 2017 to January 2019. Intraocular pressure (IOP), visual acuity, surgical success rates, medications, and complications were monitored at post-operative 1 day, 1 week, 1, 3, 6, 12 and 24 months. Surgical success criteria were defined as 6 mm Hg≤IOP≤21 mmHg with or without additional medications. Our results showed that average IOP was statistically significant between pre-operative visit and each follow-up visit (all P <0.05). The total success rate of trabeculo-canalectomy at 1, 3, 6, 12 and 24 months was 92.5%, 86.8%, 94.3%, 92.5% and 90.6% respectively. After 3 months post-operatively, all patients had no obvious filtering blebs. The main early complications included postoperative hyphema (7.5%), elevated IOP (5.7%) and anterior chamber exudation (3.8%), which were all cured after conservative treatment. No blebitis, shallow anterior chamber, choroidal detachment and endophthalmitis were observed. Logistic regression analysis showed that patients with secondary glaucoma were more likely to undergo surgical failure 24 months post-operatively (P= 0.008). Thus, we conclude that trabeculo-canalectomy is effective and safe for the treatment of glaucoma.

Study on the effectiveness and safety of Foldable Capsular Vitreous Body implantation

Background

Foldable capsular vitreous body (FCVB) was designed to treat severe retinal detachment. The aim of this study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body in 1-year follow-up.

Methods

A retrospective analysis was conducted for 20 patients with severe ocular trauma or silicone oil (SO) dependent eyes underwent vitrectomy and FCVB implantation in a 1-year follow-up. All treated eyes were peformed clinical examinations involved the visual acuity (VA) examination, Goldmann applanation tonometer, noncontact specular microscopy, fundus photography, B-Scan examination and optical coherence tomography (OCT). The groups were compared with t-test and the McNemar - Bowker test.

Results

In 1-year follow-up, 20 eyes were evaluated in the study. FCVB well supported the vitreous retina in all treated eyes, and 6 treated eyes achieved retinal reattachment 12 months after FCVB implantation. There were no significant differences in VA before and after FCVB implantation (P = 1.000). In addition, the postoperative IOP markedly elevated from the preoperative IOP of 12.90 ± 7.06 mmHg to 15.15 ± 3.36 mmHg (P = 0.000017). The intraocular pressure (IOP) of 10 eyes maintained at a normal level after surgeries. The other 10 eyes showed slightly lower IOP within the acceptable level. Though two patients developed keratopathy and ocular inflammation respectively, other treated eyes were symmetric with fellow eyes showing satisfactory appearance. Moreover, there was no SO emulsification or leakage happened in the observation.

Conclusions

FCVB implantation was an effective and safe treatment in the eyes with severe retinal detachment.

Effects of Toll-Like Receptor 4 Inhibition on Transforming Growth Factor-β2 Signaling in the Human Trabecular Meshwork

Purpose: Transforming growth factor-β2 (TGFβ2) and Toll-like receptor 4 (TLR4) crosstalk have been implicated in extracellular matrix regulation in the trabecular meshwork (TM) and ocular hypertension in mice. We investigated TLR4 expression in normal and glaucomatous human trabecular meshwork (HTM) sections and utilized a human perfusion organ culture model to determine TGFβ2-TLR4 signaling crosstalk in glaucoma. Methods: Expression of TLR4 was determined in TM of normal and glaucomatous human eyes. Anterior segments of paired human eyes were perfused at a constant flow rate (2.5 μL/min) for 4 days to acquire stable baseline intraocular pressures (IOPs). We treated paired eyes with two different treatment paradigms: (1) TGFβ2 in one eye and vehicle control in the paired eye, (2) TGFβ2 in one eye and TGFβ2 + TLR4 inhibitor TAK-242 in the paired eye. Perfusate and TM tissue were collected and analyzed for fibronectin (FN) and collagen IV (COLIV) expression. Results: We observed increased TLR4 expression in glaucomatous HTM sections compared to normal (age-matched) (P < 0.05). Significant elevation of IOP was detected in 47% of TGFβ2-treated anterior segments (P < 0.01) compared to control, and in TGFβ2 treated compared with co-treatment with TGFβ2 + TLR4 inhibitor (P < 0.0001). An increase in FN and COLIV expression was observed after TGFβ2 treatment, and inhibition of TLR4 signaling decreased TGFβ2-induced FN and COLIV expression in perfusate (P < 0.05). Conclusions: These studies identify TGFβ2-TLR4 crosstalk as a novel pathway in glaucoma. They provide a potential new target to lower IOP and explore glaucoma pathogenesis.