Malignant glaucoma treated by low-dose laser cycloplasty: a 1-year multicenter prospective non-comparative study.

AIM: To report a one-year clinical outcomes of low-dose laser cycloplasty (LCP) among malignant glaucoma patients. METHODS: In this prospective, multicenter, non-comparative clinical study, participants with malignant glaucoma were recruited and underwent LCP at eight ophthalmic centers in China. Patients were followed up at 1wk, 1, 3, 6, and 12mo. Intraocular pressure (IOP), number of glaucoma medications, anterior chamber depth (ACD), and complications were recorded. Anatomical success was defined as the reformation of the anterior chamber based on slit-lamp biomicroscopy. Recurrence was defined by the presence of a shallow or flat anterior chamber after initial recovery from treatment. RESULTS: A total of 34 eyes received LCP. Mean IOP and medications decreased from 36.1±11.5 mm Hg with 3.3±1.5 glaucoma medications pre-treatment to 20.9±9.8 mm Hg (P<0.001) with 2.9±1.6 medications (P=0.046) at 1d, and 17.4±6.7 mm Hg (P<0.001) with 1.3±1.7 medications (P<0.001) at 12mo. The ACD increased from 1.1±0.8 mm at baseline to 1.7±1.0 mm and to 2.0±0.5 mm at 1d and 12mo, respectively. A total of 32 (94.1%) eyes achieved initial anatomical success. During follow-up, 2 (5.9%) eyes failed and 8 (23.5%) eyes relapsed, yielding a 12-month anatomical success rate of 64.3%. Complications including anterior synechia (8.82%), choroidal/ciliary detachment (5.88%) and hypopyon (2.94%) were observed within 1wk. CONCLUSION: LCP is simple, safe, and effective in reforming the anterior chamber in malignant glaucoma.

Circulating Small Extracellular Vesicles Involved in Systemic Regulation Respond to RGC Degeneration in Glaucoma.

Glaucoma is a leading cause of irreversible blindness worldwide and is characterized by progressive retinal ganglion cell (RGC) degeneration and vision loss. Since irreversible neurodegeneration occurs before diagnosable, early diagnosis and effective neuroprotection are critical for glaucoma management. Small extracellular vesicles (sEVs) are demonstrated to be potential novel biomarkers and therapeutics for a variety of diseases. In this study, it is found that intravitreal injection of circulating plasma-derived sEVs (PDEV) from glaucoma patients ameliorated retinal degeneration in chronic ocular hypertension (COH) mice. Moreover, it is found that PDEV-miR-29s are significantly upregulated in glaucoma patients and are associated with visual field defects in progressed glaucoma. Subsequently, in vivo and in vitro experiments are conducted to investigate the possible function of miR-29s in RGC pathophysiology. It is showed that the overexpression of miR-29b-3p effectively prevents RGC degeneration in COH mice and promotes the neuronal differentiation of human induced pluripotent stem cells (hiPSCs). Interestingly, engineered sEVs with sufficient miR-29b-3p delivery exhibit more effective RGC protection and neuronal differentiation efficiency. Thus, elevated PDEV-miR-29s may imply systemic regulation to prevent RGC degeneration in glaucoma patients. This study provides new insights into PDEV-based glaucoma diagnosis and therapeutic strategies for neurodegenerative diseases.

Central anterior chamber depth correlated with white-to-white distance in normal, long, and short eyes.

PURPOSE: To explore the associations between central anterior chamber depth (CACD) and other anterior segment biometric parameters and to determine the possible determinants of CACD in short, normal, and long eyes. METHODS: The biometric data of pre-operation patients aged 50-80 years with coexisting cataract and primary angle-closure disease or senile cataract were reviewed. Axial length (AL), CACD, lens thickness (LT), central corneal thickness (CCT), and white-to-white distance (WTW) were measured by Lenstar optical biometry (Lenstar 900). The data of 100 normal eyes (AL = 22 to 26 mm), 100 short eyes (AL ≤ 22 mm), and 100 long eyes (AL ≥ 26 mm) were consecutively collected for subsequent analyses. RESULTS: The mean age of the subjects was 66.60 ± 7.85 years, with 25.7% of the sample being men. Both CACD and WTW were found to be smallest in short eyes and were smaller in normal eyes than in long eyes (F = 126.524, P < 0.001; F = 28.458, P < 0.001). The mean LT was significantly thicker in short eyes than in normal and long eyes (4.66 mm versus 4.49 mm versus 4.40 mm; F = 18.099, P < 0.001). No significant differences were observed in CCT between the three AL groups (F = 2.135, P = 0.120). Stepwise regression analysis highlighted AL, LT, and WTW as three independent factors associated with CACD in the normal AL group. In the short AL group and long AL group, LT and WTW were independent factors associated with CACD. CONCLUSIONS: CACD increases as AL elongates and reaches a peak when AL exceeds 26 mm. Furthermore, CACD showed inverse correlation with LT and positive correlation with WTW. A relatively small WTW results in an anteriorly positioned lens, and thus, a decrease in CACD.

Effect of low dose laser cycloplasty on deepening anterior chamber in chronic angle-closure glaucoma.

AIM: To describe the outcome of using low-dose laser cycloplasty (LCP) in chronic angle-closure glaucoma (CACG). METHODS: A retrospective case series. Medical charts of CACG patients who underwent LCP in the Eye Hospital of Wenzhou Medical University were reviewed. The main outcomes included intraocular pressure (IOP), the number of glaucoma medication, anterior segment parameters and surgery-related complications. RESULTS: A total of 7 eyes of 7 CACG patients (age 38.9±11.0y) underwent LCP with a mean follow-up of 27.1±13.7mo (range 16-48mo). Following LCP, mean IOP and glaucoma medications decreased from 26.1±6.1 mm Hg with 3.1±1.1 glaucoma medications pre-treatment to 14.9±3.1 mm Hg (P=0.027) with 0.4±1.1 glaucoma medications (P=0.001) at final follow-up. The anterior chamber depth (ACD), angle opening distance500 and trabecular-iris angle increased from 1.65±0.33 mm, 0.05 mm (range 0-0.30 mm) and 5.1° (range, 0-31.97°) at baseline to 1.98±0.43 mm (P=0.073), 0.53 mm (range 0.42-0.91 mm, P=0.015), 45.9° (range, 40.2°-59.4°, (P=0.015) in the long-term follow-up, respectively. The deepening of ACD and reopening of anterior chamber angle (ACA) was observed in 6 eyes (85.7%). CONCLUSION: LCP is a promising treatment option for patients with CACG via reducing IOP and glaucoma medication without serious complications. In addition, LCP can bring a significant deepening in ACD and reopening of ACA.

Intraocular Pressure and Myopia Progression, Axial Length Elongation in Rural Chinese Children.

SIGNIFICANCE: This study reported the relationship between intraocular pressure (IOP) and myopia progression, which helps to understand more comprehensively whether IOP can be an important reference factor to intervene in the progression of myopia. PURPOSE: This study aimed to investigate the association between IOP and myopia progression as well as axial length elongation in rural Chinese children. METHODS: A total of 598 (598 of 878 [68.1%]) children (6 to 17 years) from the baseline Handan Offspring Myopia Study who completed a 3.5-year follow-up vision examination were included. Ocular examinations at both visits included cycloplegic autorefraction, IOP, and axial length measurements. RESULTS: Children with myopia had the highest baseline IOP of the three refractive groups (14.13 ± 1.31, 13.78 ± 1.71, and 13.59 ± 1.64 mmHg in myopes, emmetropes, and hyperopes, respectively, P = .002). However, IOPs showed no significant difference between eyes with or without newly developed myopia (13.63 ± 1.68 vs. 13.89 ± 1.68, P = .16), with or without faster myopia progression (13.75 ± 1.61 vs. 13.86 ± 1.63, P = .46), or with axial length elongation (13.80 ± 1.61 vs. 13.76 ± 1.64, P = .80). The multivariate regression analysis demonstrated that neither baseline refractive error ( ß = -0.082, P = .13) nor baseline axial length ( ß = -0.156, P = .08) was associated with baseline IOP. CONCLUSIONS: Myopic eyes have slightly higher IOP compared with emmetropic and hyperopic eyes, although it was not clinically significant. However, IOP was not found to be associated with either myopia progression or axial length elongation in this cohort sample of rural Chinese children.

ASSOCIATION OF OCULAR PERFUSION PRESSURE AND CEREBROSPINAL FLUID PRESSURE WITH CHANGES IN DIABETIC RETINOPATHY.

PURPOSE: To investigate the association between mean ocular perfusion pressure (MOPP), estimated cerebrospinal fluid pressure (CSFP), and changes in diabetic retinopathy (DR) in a Northeastern Chinese population with Type 2 diabetes. METHODS: A total of 1,322 subjects from the Fushun Diabetic Retinopathy Cohort Study were enrolled. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and intraocular pressure (IOP) were recorded. MOPP was calculated by the following formula: MOPP = 2/3 [DBP + 1/3 (SBP - DBP)] - IOP, and CSFP was estimated according to the following formula: CSFP = 0.44 × body mass index + 0.16 × DBP - 0.18 × age - 1.91. New development, progression, and regression of DR were graded based on fundus photographs at baseline and during follow-up examinations with a mean interval of 21.2 months using the modified Early Treatment Diabetic Retinopathy Study criteria. RESULTS: Increasing MOPP was associated with the incidence of DR in the multivariate model (per 1-mmHg increase: relative risk, 1.06; 95% confidence interval, 1.02-1.10; P = 0.007) and showed a borderline negative association with DR regression (per 1-mmHg increase: relative risk, 0.98; 95% confidence interval, 0.97-1.00; P = 0.053). However, MOPP was not associated with progression of DR. Cerebrospinal fluid pressure was not associated with new development, progression, or regression of DR. CONCLUSION: The MOPP, but not the CSFP, was found to influence the development, but not the progression of DR in this Northeastern Chinese cohort.

Trend of glaucoma internal filtration surgeries in a tertiary hospital in China.

AIM: To evaluate the trend of glaucoma internal filtration surgeries for inpatients between 2015 and 2021 at the Eye Hospital of Wenzhou Medical University. METHODS: A review of the medical records of inpatients who had been diagnosed with glaucoma and received anti-glaucoma surgery between January 1, 2015 and December 31, 2021 was conducted. The glaucoma diagnosis in this study included primary open angle glaucoma, primary angle-closure glaucoma, secondary glaucoma, and paediatric glaucoma. The types of surgeries were categorised as internal filtration, external filtration, and cyclodestruction surgery based on the pathway of aqueous humor outflow. The trend of these glaucoma surgeries in the sample of patients with different types of glaucoma was then analysed. RESULTS: The number of patients hospitalised for glaucoma surgery increased yearly, from 752 in 2015 to 1373 in 2021, at the Eye Hospital of Wenzhou Medical University. Regarding the patients diagnosed with primary open angle glaucoma, internal filtration surgery increased from 27.40% of the sample to 54.40% of the sample, while external filtration surgery decreased from 71.50% to 44.20% between 2015 and 2021. For paediatric glaucoma, internal filtration surgery increased from 37.50% in 2015 to 88.20% in 2021. Whilst different types of surgeries were performed on the sample of patients with secondary glaucoma, the proportion of internal filtration surgery also showed an increase from 18.20% in 2015 to 40.90% in 2021. Meanwhile, internal filtration surgery in the patient sample with primary angle-closure glaucoma already accounted for over 70.00% in 2015, and showed a small increase by 2021. CONCLUSION: As surgical technology and surgical experience continue to elevate and improve, the range of glaucoma surgeries are correspondingly evolving. This study find that internal filtration surgeries accounted for an increasing proportion of treatments in the surgical management of glaucoma between 2015 and 2021.

Refractive Error in a Chinese Population with Type 2 Diabetes: A Report from the Fushun Diabetic Retinopathy Cohort Study.

PURPOSE: To describe the prevalence and risk factors for refractive errors in a northeastern Chinese population with type 2 diabetes. METHODS: Subjects (age ≥30 years) from a community-based study, the Fushun Diabetic Retinopathy Cohort Study, were enrolled. All subjects underwent comprehensive ocular examinations, including autorefraction. Myopia, high myopia, and hyperopia were defined as a spherical equivalent (SE) of the right eye <-0.5 diopter (D), <-5.0D, and >0.5D, respectively. Astigmatism was defined as cylinder <-0.5D in a minus cylinder prescription. Anisometropia was defined as a difference of SE >1.0D between two eyes. RESULTS: A total of 1929 participants (790 males, 41.0%) were enrolled. The age and gender standardized prevalence of myopia, high myopia, hyperopia, astigmatism, and anisometropia were 43.1% (95% confidence interval [CI]: 40.9%-45.3%), 8.5% (95% CI: 7.3%-9.8%), 21.5% (95% CI: 19.7%-23.4%), 61.0% (95% CI: 58.9%-63.2%), and 17.2% (95% CI: 15.5%-18.9%), respectively. Advancing age was associated with a higher frequency of hyperopia, astigmatism, and anisometropia, as opposed to a lower frequency of myopia. Female (adjusted odds ratio [aOR], 1.27; 95% CI, 1.02-1.57) participants, higher intraocular pressure (aOR, 1.03; 95% CI, 1.00-1.07), and lenticular opacity (aOR, 1.53; 95% CI, 1.20-1.94) were also found to be associated with myopia. Long duration of diabetes (>15 years) was found to be a significant factor for astigmatism (aOR, 1.62; 95% CI, 1.15-2.27) and anisometropia (aOR, 1.87; 95% CI, 1.29-2.71). CONCLUSION: Nearly two-thirds of participants with type 2 diabetes had a refractive error. Age is a common factor with different types of refractive errors.

A Novel and Reversible Experimental Primate Ocular Hypertension Model: Blocking Schlemm's Canal.

INTRODUCTION: The purpose of this study was to establish a novel and reversible experimental ocular hypertension primate model by blocking Schlemm's canal. METHODS: A model was induced in adult cynomolgus monkeys (n=4) by blocking Schlemm's canal with an inserted microcatheter (200 µm diameter); it was removed 6 weeks later from one monkey to reverse the elevated intraocular hypertension. All animals were monitored for 11 months; weekly measurements of intraocular pressure and biweekly examinations with spectral domain optical coherence tomography and disc photography were performed. Histopathology of the eye and retinal ganglion cell counts were completed at the end of the study. RESULTS: The intraocular pressure of the blocked eyes was significantly higher than that of the contralateral eyes at 1 month after the blockage (P <0.001); the mean intraocular pressure was similar to the contralateral eye from 1 week to 11 months after the microcatheter was removed in monkey A (P=0.170). The mean intraocular pressure of the blocked eyes of the remaining monkeys was significantly higher than that of the contralateral eyes throughout the follow-up period (P <0.001). The fundus imaging showed decreases in the retinal nerve fibre layer thickness, and localised defects were observed in two blocked eyes. A histological examination demonstrated that the number of retinal ganglion cells in blocked eyes of monkeys A, B, and C was significantly decreased compared with the control. CONCLUSION: Schlemm's canal blockage alone in the monkey model produces sustained elevation of intraocular pressure, which present a novel animal model for studying the pathogenesis of glaucoma.

A new bleb-independent surgery namely penetrating canaloplasty for corticosteroid-induced glaucoma: a prospective case series.

AIM: To report the outcomes of penetrating canaloplasty for corticosteroid-induced glaucoma in a case series. METHODS: Penetrating canaloplasty is a bleb-independent filtering surgery unifying canaloplasty and trabeculectomy. In this study, the surgery was performed to restore the natural outflow through surgically expanded Schlemm's canal and generated trabeculum ostium. A total of 10 eyes of 8 patients were treated with penetrating canaloplasty for corticosteroid-induced glaucoma. Intraocular pressure (IOP) and the number of glaucoma medications at postoperative 3, 6, 12, 18, 24, 36, and 48mo were documented as primary endpoint. Complications after the surgery were recorded as secondary endpoint. RESULTS: Penetrating canaloplasty was accomplished successfully for all 10 eyes, with a mean follow-up of 20.4±13.0mo (range 6-48mo). The mean preoperative IOP and number of anti-glaucoma medications were 45.1±6.5 mm Hg and 3.3±0.5 respectively. The mean post-operative IOP at 3, 6, 12, 18, 24, 36, and 48mo were 15.8±6.0, 14.7±3.3, 15.3±2.0, 15.6±2.6, 17.5±1.8, 16.5±4.9, and 14.0 mm Hg. The number of anti-glaucoma medications at these time points were all 0. This surgery failed to control the IOP in 1 eye at 1mo after surgery. Hyphaema occurred in 3 eyes on the first day after surgery. Postoperative transient IOP increasing was encountered with in two eyes from 1wk to 1mo after surgery. Choroidal detachment developed in one eye but responded well to conservative treatment. CONCLUSION: Penetrating canaloplasty is effective for corticosteroid-induced glaucoma without serious complications, making it a viable or preferred alternative option.