Angle-closure: risk factors, diagnosis and treatment

Ophthalmological examination and imaging features that better predict risk of Angle Closure in siblings

OBJECTIVE

Characteristics of individuals with angle closure may be useful in targeted screening of family members. Here, we assess if findings gathered during examination and imaging of patients with a known angle closure diagnosis (probands) could better determine the risk of angle closure in the patients' siblings.

DESIGN

Cross-sectional study of patients with known angle closure and their siblings.

SUBJECTS

Participants, and Controls: South Indian patients (probands) 30 years and older with open angles, suspect primary angle closure (PACS), or primary angle closure/primary angle closure glaucoma (PAC/PACG), and a biological sibling age 30 years or older (n=292 proband/sibling pairs).

METHODS

Demographic data, relevant ocular history, and a comprehensive ophthalmic examination with Anterior Segment Optical Coherence Tomography (ASOCT) were obtained. Three clinically relevant models were created to analyze the contribution of specific proband factors in predicting sibling angle closure diagnosis, using demographic (age, gender), ocular exam (gonioscopy, optic nerve exam, visual acuity, intraocular pressure [IOP]), and ASOCT features to improve prediction beyond proband diagnosis alone evaluated by log likelihood ratio testing and statistical comparison of receiver operating characteristics (ROC).

MAIN OUTCOME MEASURES

Sibling angle closure diagnostic accuracy.

RESULTS

Demographic and ocular exam metrics did not improve the prediction of sibling angle closure for all three outcomes (sibling diagnosis: (1) PACS/PAC/PACG vs OA, (2) PAC/PACG vs PACS/OA, and (3) PAC/PACG vs PACS), adding no model improvement when compared to diagnosis alone. Models adding ASOCT metrics to the prior model including proband diagnosis, demographics and ocular exam measures led to significantly improved prediction of 2 of the 3 angle closure outcomes. Specifically, improvement was noted via likelihood ratio testing for prediction of PAC/PACG vs PACS/OA (p=0.01), or PAC/PACG vs PACS (p=0.001). For all 3 angle closure outcomes, ROC comparisons demonstrated significant improvement in AUC between the three models predicting sibling outcomes, demonstrating an increase in AUC with each successive nested model across all 3 sibling angle closure outcomes.

CONCLUSIONS

Structural features of eyes with angle closure may assist in stratifying the risk of angle closure in patients' siblings. Further studies should consider evaluating this approach to achieve more targeted screenings.

Iris Morphological and Biomechanical Factors Influencing Angle Closure During Pupil Dilation

Purpose

To use finite element (FE) analysis to assess what morphologic and biomechanical factors of the iris and anterior chamber are more likely to influence angle narrowing during pupil dilation.

Methods

The study consisted of 1344 FE models comprising the cornea, sclera, lens, and iris to simulate pupil dilation. For each model, we varied the following parameters: anterior chamber depth (ACD = 2-4 mm) and anterior chamber width (ACW = 10-12 mm), iris convexity (IC = 0-0.3 mm), iris thickness (IT = 0.3-0.5 mm), stiffness (E = 4-24 kPa), and Poisson's ratio (v = 0-0.3). We evaluated the change in (△∠) and the final dilated angles (∠f) from baseline to dilation for each parameter.

Results

The final dilated angles decreased with a smaller ACD (∠f = 53.4° ± 12.3° to 21.3° ± 14.9°), smaller ACW (∠f = 48.2° ± 13.5° to 26.2° ± 18.2°), larger IT (∠f = 52.6° ± 12.3° to 24.4° ± 15.1°), larger IC (∠f = 45.0° ± 19.2° to 33.9° ± 16.5°), larger E (∠f = 40.3° ± 17.3° to 37.4° ± 19.2°), and larger v (∠f = 42.7° ± 17.7° to 34.2° ± 18.1°). The change in angles increased with larger ACD (△∠ = 9.37° ± 11.1° to 15.4° ± 9.3°), smaller ACW (△∠ = 7.4° ± 6.8° to 16.4° ± 11.5°), larger IT (△∠ = 5.3° ± 7.1° to 19.3° ± 10.2°), smaller IC (△∠ = 5.4° ± 8.2° to 19.5° ± 10.2°), larger E (△∠ = 10.9° ± 12.2° to 13.1° ± 8.8°), and larger v (△∠ = 8.1° ± 9.4° to 16.6° ± 10.4°).

Conclusions

The morphology of the iris (IT and IC) and its innate biomechanical behavior (E and v) were crucial in influencing the way the iris deformed during dilation, and angle closure was further exacerbated by decreased anterior chamber biometry (ACD and ACW).

Long-term effects of mild cataract extraction versus laser peripheral iridotomy on anterior chamber morphology in primary angle-closure suspect eyes

AIM

To compare lens extraction (LE) and laser peripheral iridotomy (LPI) on anterior segment morphology in primary angle-closure suspect (PACS) eyes.

METHODS

This prospective clinical trial included 144 patients with PACS who underwent either LPI or LE. Ultrasound biomicroscopy (UBM) and gonioscopy were performed before and 1 month and 2 years after operation. Main outcomes included UBM parameters and the percentage of residual angle closure.

RESULTS

At both 1 month and 2 years of follow-up, LE showed a better effect of relieving anterior chamber crowding and widening the drainage angle, as obtaining a larger anterior chamber depth (ACD), angle opening distance, trabecular iris angle (TIA), trabecular iris space area, trabecular ciliary process distance (TCPD) and a smaller iris curvature (I-Curv) and lens vault (LV) (p<0.001). In the LPI group, angle width increased (angle opening distance at 500 µm from the scleral spur, TIA and trabecular iris space area at 500 µm from the scleral spur) and I-Curv decreased (p<0.001) at 1 month postoperatively, with no significant changes in ACD, LV or TCPD. However, at 2 years after LPI, the angle narrowed with the increase in LV over time, and the proportion of residual angle closure also increased from 21.7% to 30.4% (p<0.001). In contrast, after LE, the widened angle width, flattened iris, deepened ACD, decreased LV and increased TCPD all showed good sustainability in the comparison between 1-month and 2-year follow-up. No residual angle closure was observed either at 1 month or 2 years after LE.

CONCLUSIONS

LE was prior to LPI in widening the drainage angle. After LPI, there was a narrowing of the angle and an increase in the proportion of residual angle closure over time. LE could achieve a wider angle with no residual angle closure, and the anterior segment parameters were sustainable.

TRIAL REGISTRATION NUMBER

ChiCTR1800016511.

Blind Spots in Therapy: Unveiling Drug-Induced Angle-Closure Glaucoma Through a National Analysis

OBJECTIVE

To identify and quantify medications causing angle-closure glaucoma through the FDA Adverse Event Reporting System (FAERS).

DESIGN

National retrospective database analysis.

SUBJECTS

There were 11 737 133 total adverse event reports from the FDA Federal Adverse Event Reporting System (FAERS) database 2004 to third quarter of 2023 (2023Q3), which included 1629 reports of angle-closure glaucoma.

METHODS

Drugs associated with reports of angle-closure glaucoma were identified in FAERS through disproportionality analysis MAIN OUTCOME MEASURES: To ascertain if these reports yielded statistically significant signals, we used the proportional reporting ratio (PRR), reporting odds ratio (ROR), empirical Bayes geometric mean (EBGM), and information component (IC). We considered a signal to be detected when all 4 disproportionality analysis metrics were positive.

RESULTS

We identified a total of 1629 adverse event reports linked to 611 suspected drugs over the course of 20 years (2004-2023Q3). Frequently reported drugs included topiramate (520 reports) and citalopram (69 reports), amongst many others. Eighteen medications yielded a positive signal, including lesser-known medications like olanzapine, phentermine, and ranibizumab. Tropicamide exhibited the most robust statistical significance (n = 18; PRR: 164.263; ROR [95% confidence interval {CI}]: 167.95 [104.994-268.655]; EBGM [EBGM05]: 162.421 [109.5]; IC [IC05]: 7.344 [4.591]), while acetazolamide was the second strongest (n = 51; PRR: 113.088; ROR 95% CI: 114.782 [86.665-152.021]; EBGM [EBGM05]: 109.506 [86.501]; IC [IC05]: 6.775 [5.115]).

CONCLUSIONS

Drug-induced glaucoma included both well-known medications such as topiramate as well as lesser-known medications such as olanzapine, phentermine, and ranibizumab. Clinician awareness of these findings is important.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Acute angle-closure in juvenile X-linked retinoschisis

Juvenile X-linked retinoschisis (JXR), the most common inherited retinal disorder in young males, presents with a wide range of phenotypic variations. Acute angle closure in children with JXR has been reported in the literature only once before. We present a case of acute-angle closure, temporally associated with pharmacologic dilation, in a 12-year-old boy with JXR.

Ocular manifestations of common pulmonary diseases: a narrative review

Several pulmonary disorders can cause ocular involvement. Understanding these manifestations is critical for early diagnosis and treatment. Hence, we set out to examine the most common ocular manifestations of asthma, chronic obstructive pulmonary disease (COPD), sarcoidosis, obstructive sleep apnea (OSA), and lung cancer. Allergic keratoconjunctivitis and dry eye are two ocular manifestations of bronchial asthma. The inhaled corticosteroids used to treat asthma can cause cataract formation. COPD is associated with ocular microvascular changes as a result of chronic hypoxia and systemic inflammation spillover into the eyes. Its clinical significance, however, is unknown. Ocular involvement is common in sarcoidosis, occurring in 20% of cases of pulmonary sarcoidosis. It can affect nearly any anatomical structure of the eye. Obstructive sleep apnea has been linked to floppy eye syndrome, glaucoma, non-arteritic anterior ischemic optic neuropathy, keratoconus, retinal vein occlusion, and central serous retinopathy, according to research. However, while an association has been established, causality has yet to be established. The effect of positive airway pressure (PAP) therapy used to treat OSA on the aforementioned ocular conditions is unknown. PAP therapy can cause eye irritation and dryness. Lung cancer can affect the eyes through direct nerve invasion, ocular metastasis, or as part of a paraneoplastic syndrome. The goal of this narrative review is to raise awareness about the link between ocular and pulmonary disorders in order to aid in the early detection and treatment of these conditions.

Low-dose transscleral cyclophotocoagulation with subsequent phacoemulsification in the treatment of prolonged acute primary angle closure

BACKGROUND

To explore the outcomes and mechanisms of intraocular pressure (IOP) control using low-dose transscleral cyclophotocoagulation (LDTSCP) followed by phacoemulsification in patients with prolonged acute primary angle closure (APAC).

METHODS

Patients with prolonged APAC refractory to all other treatment modalities were prospectively recruited, and underwent LDTSCP (10 shots, 2 s duration, 120° treatment with the energy starting at 1500 mW and titrated to the level with audible burst but not exceeding 2000 mW) and anterior chamber paracentesis 1 week prior to phacoemulsification with intraocular lens implantation and viscogoniosynechiolysis. Postoperative IOP, vision, anatomic changes on anterior segment optical coherence tomography and complications were recorded.

RESULTS

Twenty eyes with prolonged APAC were recruited. Median follow-up was 12 months (range 9-18), at which point the vision in all eyes had improved and IOP was ≤17 mm Hg on no antiglaucoma medications. Following LDTSCP at postoperative day (POD) 1, IOP decreased in all eyes to a median 15 mm Hg (range: 6-28 mm Hg). Post-LDTSCP supraciliary effusion (SCE) occurred in 90% of eyes on POD1 or POD7 and ciliary body defect (CBD) was detected in 30% of eyes and resolved in all cases by postoperative month 1. Lower post-LDTSCP IOP was associated with more number of bursts (r=-0.558, p=0.011) and higher grade of SCE (r=-0.877, p<0.001), but not with total energy (p=0.240). Eyes with CBD (p=0.018) and a higher number of bursts (r=0.657, p=0.002) had higher grade SCE.

CONCLUSIONS

LDTSCP-induced SCE may explain the post-LDTSCP IOP reduction seen in eyes with prolonged APAC. LDTSCP instead of traditional more extensive treatment, was sufficient to provide a relatively safe and effective bridge therapy prior to phacoemulsification.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trials Registry (ChiCTR1900023567).

The inflammatory cytokine profiles and ocular biometric characteristics of primary angle-closure glaucoma

OBJECTIVE

To investigate the pathogenesis of primary angle-closure disease (PACG) by measuring the anatomical structures of the anterior and posterior segments of the eye and inflammatory markers in the peripheral blood.

METHODS

This case-control study enrolled patients diagnosed with acute PACG (APACG) and chronic PACG (CPACG). It also enrolled control subjects without PACG. The anterior and posterior anatomical features were measured in all study participants. The levels of interleukin (IL)-6, tumour necrosis factor-α and the neutrophil-to-lymphocyte ratio (NLR) in the peripheral blood were measured.

RESULTS

This study analysed a total of 99 eyes: 34 eyes from 34 patients with APACG, 28 eyes from 28 patients with CPACG and 37 eyes from 37 control patients with senile cataract. The axis length, corneal diameter, anterior chamber depth and anterior chamber volume were significantly smaller in the APACG and CPACG groups compared with the controls. The level of IL-6 in the peripheral blood of patients with PACG was significantly lower than that of the controls. The NLR in the peripheral blood of patients with PACG was significantly greater than that of the controls.

CONCLUSIONS

Changes in the ocular anatomy and some inflammatory markers might be involved in the pathogenesis of PACG.

[Predictors of the success of laser peripheral iridotomy and lensectomy in the early stages of primary angle closure disease]

The article reviews literature data on the search for predictors of the success of laser peripheral iridotomy (LPI) and lensectomy in the early stages of primary angle closure disease (PACD) and presents a trend analysis of the studies conducted on individuals identified as primary angle closure suspects (PACs) and those with primary angle closure (PAC). The concept of the review was determined by the ambiguous choice of treatment for patients at the stage of PAC onset. Determining the success predictors of LPI or lensectomy plays a key role in optimizing the treatment of PACD. The results of literature analysis are contradictory, which indicates the need for further research taking into account modern methods of visualization of the eye structures such as optical coherence tomography (OCT), Swept Source OCT (SS-OCT), and the use of uniform criteria for evaluating the effectiveness of treatment.

Perioperative Care of the Patient with Eye Pathologies Undergoing Nonocular Surgery

The authors reviewed perioperative ocular complications and implications of ocular diseases during nonocular surgeries. Exposure keratopathy, the most common perioperative eye injury, is preventable. Ischemic optic neuropathy, the leading cause of perioperative blindness, has well-defined risk factors. The incidence of ischemic optic neuropathy after spine fusion, but not cardiac surgery, has been decreasing. Central retinal artery occlusion during spine fusion surgery can be prevented by protecting eyes from compression. Perioperative acute angle closure glaucoma is a vision-threatening emergency that can be successfully treated by rapid reduction of elevated intraocular pressure. Differential diagnoses of visual dysfunction in the perioperative period and treatments are detailed. Although glaucoma is increasingly prevalent and often questions arise concerning perioperative anesthetic management, evidence-based recommendations to guide safe anesthesia care in patients with glaucoma are currently lacking. Patients with low vision present challenges to the anesthesia provider that are becoming more common as the population ages.

Is there an association of socioeconomic deprivation with acute primary angle closure?

BACKGROUND

Socioeconomic deprivation is known to increase the risk of late presentation of many diseases. This is the largest study in United Kingdom investigating the relationship between socioeconomic deprivation and acute primary angle closure (APAC).

METHODS

A retrospective review of case notes was conducted of 718 consecutive patients who underwent laser peripheral iridotomy (LPI) in Edinburgh (Princess Alexandra Eye Pavilion) and Fife (Queen Margaret Hospital) between 2015 and 2019. Baseline demographics including sex, age, ethnicity, pre-existing diabetes, use of anti-depressants, and family history of glaucoma were collected. Deprivation was scored using the Scottish Index of Multiple Deprivation (SIMD) Index 2020v2. A lower rank and decile indicate higher degrees of deprivation. We investigated differences in characteristics between patients who were referred routinely versus patients who referred as APAC.

RESULTS

The SIMD rank and deciles were consistently lower in patients who were referred urgently with APAC in both centres (P = <0.05) when compared to those referred routinely for LPI. On univariate and multivariate logistic regression, the presentation of APAC is negatively associated with SIMD Decile (OR = -0.101, 95% CI -0.178 to -0.026, P = 0.008) and family history of glaucoma (OR = -1.010, 95% CI -1.670 to -0.426, P = 0.001), and positively associated with age (OR = 0.029, 95% CI 0.009-0.049, P = 0.004).

CONCLUSIONS

Socioeconomic deprivation is an important risk factors for patients presenting with APAC. Socioeconomic deprivation should be incorporated into the design of glaucoma services and considered when triaging patients for prophylactic and therapeutic LPI and cataract surgery.

The genetics of glaucoma: Disease associations, personalised risk assessment and therapeutic opportunities-A review

Glaucoma refers to a heterogenous group of disorders characterised by progressive loss of retinal ganglion cells and associated visual field loss. Both early-onset and adult-onset forms of the disease have a strong genetic component. Here, we summarise the known genetic associations for various forms of glaucoma and the possible functional roles for these genes in disease pathogenesis. We also discuss efforts to translate genetic knowledge into clinical practice, including gene-based tests for disease diagnosis and risk-stratification as well as gene-based therapies.

Corneal-compensated intraocular pressure, Goldmann-correlated intraocular pressure and their associated factors in the geriatric population, a population-based study

PURPOSE

To determine the distribution of corneal-compensated intraocular pressure (IOPcc), Goldmann-correlated intraocular pressure (IOPg) and their associated factors in a geriatric population.

METHODS

The present cross-sectional study was performed in individuals above 60 years of age in Tehran, the capital of Iran. The sampling was performed using multi-stage random cluster sampling method. All participants underwent preliminary ocular examinations, and then imaging by Pentacam HR and IOL master 500. Measurement of IOPg, IOPcc, and corneal biomechanical indices including corneal hysteresis (CH) and corneal resistant factor (CRF) was performed in a random sub-sample using ocular response analyzer (ORA).

RESULTS

The mean IOPg and IOPcc were 16.76 ± 4.71 mmHg and 19.05 ± 4.67 mmHg, respectively. There were no statistically significant differences in both IOPg (p = 0.891) and IOPcc (p = 0.248) between males and females. Based on the multiple linear regression models, both IOPg and IOPcc showed a statistically significant direct relationship with CRF (P < 0.001) and a significant inverse relationship with CH (P < 0.001 for IOPg and IOPcc), anterior chamber angle (ACA) (p = 0.006 for IOPg and p = 0.017 for IOPcc), and spherical equivalent refractive error (p = 0.032 for IOPg and p = 0.046 for IOPcc).

CONCLUSION

Mean IOPg and IOPcc in the present study were higher compared to most previous studies. Corneal biomechanical indices including CH and CRF, refractive error and anterior chamber angle were independent associated factors of IOPg and IOPcc in the present study. There was no significant relationship between ORA-derived IOP values and CCT.

Digital Gonioscopy Based on Three-dimensional Anterior-Segment OCT: An International Multicenter Study

PURPOSE

To develop and evaluate the performance of a 3-dimensional (3D) deep-learning-based automated digital gonioscopy system (DGS) in detecting 2 major characteristics in eyes with suspected primary angle-closure glaucoma (PACG): (1) narrow iridocorneal angles (static gonioscopy, Task I) and (2) peripheral anterior synechiae (PAS) (dynamic gonioscopy, Task II) on OCT scans.

DESIGN

International, cross-sectional, multicenter study.

PARTICIPANTS

A total of 1.112 million images of 8694 volume scans (2294 patients) from 3 centers were included in this study (Task I, training/internal validation/external testing: 4515, 1101, and 2222 volume scans, respectively; Task II, training/internal validation/external testing: 378, 376, and 102 volume scans, respectively).

METHODS

For Task I, a narrow angle was defined as an eye in which the posterior pigmented trabecular meshwork was not visible in more than 180° without indentation in the primary position captured in the dark room from the scans. For Task II, PAS was defined as the adhesion of the iris to the trabecular meshwork. The diagnostic performance of the 3D DGS was evaluated in both tasks with gonioscopic records as reference.

MAIN OUTCOME MEASURES

The area under the curve (AUC), sensitivity, and specificity of the 3D DGS were calculated.

RESULTS

In Task I, 29.4% of patients had a narrow angle. The AUC, sensitivity, and specificity of 3D DGS on the external testing datasets were 0.943 (0.933-0.953), 0.867 (0.838-0.895), and 0.878 (0.859-0.896), respectively. For Task II, 13.8% of patients had PAS. The AUC, sensitivity, and specificity of 3D DGS were 0.902 (0.818-0.985), 0.900 (0.714-1.000), and 0.890 (0.841-0.938), respectively, on the external testing set at quadrant level following normal clinical practice; and 0.885 (0.836-0.933), 0.912 (0.816-1.000), and 0.700 (0.660-0.741), respectively, on the external testing set at clock-hour level.

CONCLUSIONS

The 3D DGS is effective in detecting eyes with suspected PACG. It has the potential to be used widely in the primary eye care community for screening of subjects at high risk of developing PACG.

Intra-session repeatability of anterior chamber depth across the chamber width using Pentacam Scheimpflug imaging in healthy subjects

PURPOSE

Despite the importance of anterior chamber depth (ACD) measurements in disease and ageing, the repeatability and their threshold for change is not known. Our purpose was to determine the intra-session repeatability of Pentacam Scheimpflug photography for measuring the ACD across the chamber width in healthy subjects and thus inform expected limits of normality.

METHODS

Pentacam Scheimpflug photography was used to obtain ACD measurements at 57 points across the central 8mm of the chamber width from one randomly selected eye of 130 healthy (normal vision and no ocular diseases, except age-normal cataracts) subjects (median age 58.0 years, interquartile range 46.3-63.0 years; 48 males, 82 females). Intra-session ACD measurements were compared. Univariate and multivariate linear regression was performed to identify categorical and continuous variables demonstrating a significant relationship with ACD and its repeatability.

RESULTS

Bland-Altman analyses showed no directional or depth-dependent bias in the difference between the first and second tests (mean bias -0.003 mm, 95% limits of agreement -0.115 to +0.109 mm). Multivariate analysis found gender to be a significant factor (p < 0.0001), but not age (p = 0.69) nor ethnicity (p = 0.65), although the model fit was poor (R²  = 0.004). There were no regional differences in repeatability measures found in males, but six locations in the superior aspect in females were found to be significantly different in their repeatability characteristics. Tolerance limits used to calculate the number of step sizes between <20 and >60-year-old age groups found 8.1-11.5 steps for females, and 7.5-9.2 steps for males.

CONCLUSIONS

Scheimpflug imaging using the Pentacam has excellent intra-session repeatability. Only gender appeared to affect repeatability characteristics, manifesting with a greater number of meaningful steps of change between two extremes of age range in females compared to males, which provides guidance for identifying clinically significant and measurable change between tests.

Bilateral Acute Angle Closure in a Pediatric Patient Taking Lisdexamfetamine Dimesylate (Vyvanse)

Attention-deficit/hyperactivity disorder is commonly treated with amphetamines as first line therapy. Rare case reports have shown amphetamines are associated with open angle glaucoma. We report a rare case of a 14-year-old male who presented with bilateral acute angle closure presumed to be related to his use of lisdexamfetamine dimesylate (Vyvanse). The patient's medication was discontinued which resulted in complete resolution of angle closure.

Lens extraction for chronic angle-closure glaucoma

BACKGROUND

Primary angle-closure glaucoma (PACG) is characterized by a rise in intraocular pressure (IOP) secondary to aqueous outflow obstruction, with relative pupillary block being the most common underlying mechanism. There is increasing evidence that lens extraction may relieve pupillary block and thereby improve IOP control. As such, comparing the effectiveness of lens extraction against other commonly used treatment modalities can help inform the decision-making process.

OBJECTIVES

To assess the effectiveness of lens extraction compared with other interventions in the treatment of chronic PACG in people without previous acute angle-closure attacks.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, one other database, and two trials registers (December 2019). We also screened the reference lists of included studies and the Science Citation Index database. We had no date or language restrictions.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing lens extraction with other treatment modalities for chronic PACG.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.

MAIN RESULTS

We identified eight RCTs with 914 eyes. We obtained data for participants meeting our inclusion criteria for these studies (PACG only, no previous acute angle-closure attacks), resulting in 513 eyes included in this review. The participants were recruited from a diverse range of countries. We were unable to conduct meta-analyses due to different follow-up periods and insufficient data. One study compared phacoemulsification with laser peripheral iridotomy (LPI) as standard care. Participants in the phacoemulsification group were less likely to experience progression of visual field loss (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.13 to 0.91; 216 eyes; moderate certainty evidence), and required fewer IOP-lowering medications (mean difference [MD] -0.70, 95% CI -0.89 to -0.51; 263 eyes; moderate certainty evidence) compared with standard care at 12 months. Moderate certainty evidence also suggested that phacoemulsification improved gonioscopic findings at 12 months or later (MD -84.93, 95% CI -131.25 to -38.61; 106 eyes). There was little to no difference in health-related quality of life measures (MD 0.04, 95% CI -0.16 to 0.24; 254 eyes; moderate certainty evidence), and visual acuity (VA) (MD 2.03 ETDRS letter, 95% CI -0.77 to 4.84; 242 eyes) at 12 months, and no observable difference in mean IOP (MD -0.03mmHg, 95% CI -2.34 to 2.32; 257 eyes; moderate certainty evidence) compared to standard care. Irreversible loss of vision was observed in one participant in the phacoemulsification group, and three participants in standard care at 36 months (moderate-certainty evidence). One study (91 eyes) compared phacoemulsification with phaco-viscogonioplasty (phaco-VGP). Low-certainty evidence suggested that fewer IOP-lowering medications were needed at 12 months with phacoemulsification (MD -0.30, 95% CI -0.55 to -0.05). Low-certainty evidence also suggested that phacoemulsification may have improved gonioscopic findings at 12 months or later compared to phaco-VGP (angle grading MD -0.60, 95% CI -0.91 to -0.29; TISA500 MD -0.03, 95% CI -0.06 to -0.01; TISA750 MD -0.03, 95% CI -0.06 to -0.01; 91 eyes). Phacoemulsification may result in little to no difference in best corrected VA at 12 months (MD -0.01 log MAR units, 95% CI -0.10 to 0.08; low certainty evidence), and the evidence is very uncertain about its effect on IOP at 12 months (MD 0.50 mmHg, 95% CI -2.64 to 3.64; very low certainty evidence). Postoperative fibrin reaction was observed in two participants in the phacoemulsification group and four in the phaco-VGP group. Three participants in the phaco-VGP group experienced hyphema. No data were available for progression of visual field loss and quality of life measurements at 12 months. Two studies compared phacoemulsification with phaco-goniosynechialysis (phaco-GSL). Low-certainty evidence suggested that there may be little to no difference in mean IOP at 12 months (MD -0.12 mmHg, 95% CI -4.72 to 4.48; 1 study, 32 eyes) between the interventions. Phacoemulsification did not reduce the number of IOP-lowering medications compared to phaco-GSL at 12 months (MD -0.38, 95% CI -1.23 to 0.47; 1 study, 32 eyes; moderate certainty evidence). Three eyes in the phaco-GSL group developed hyphemas. No data were available at 12 months for progression of visual field loss, gonioscopic findings, visual acuity, and quality of life measures. Three studies compared phacoemulsification with combined phaco-trabeculectomy, but the data were only available for one study (63 eyes). In this study, low-certainty evidence suggested that there was little to no difference between groups in mean change in IOP from baseline (MD -0.60 mmHg, 95% CI -1.99 to 0.79), number of IOP-lowering medications at 12 months (MD 0.00, 95% CI -0.42 to 0.42), and VA measured by the Snellen chart (MD -0.03, 95% CI -0.18 to 0.12). Participants in the phacoemulsification group had fewer complications (risk ratio [RR] 0.59, 95% CI 0.34 to 1.04), and the phaco-trabeculectomy group required more IOP-lowering procedures (RR 5.81, 95% CI 1.41 to 23.88), but the evidence was very uncertain. No data were available for other outcomes.

AUTHORS' CONCLUSIONS

Moderate certainty evidence showed that lens extraction has an advantage over LPI in treating chronic PACG with clear crystalline lenses over three years of follow-up; ultimately, the decision for intervention should be part of a shared decision-making process between the clinician and the patient. For people with chronic PACG and visually significant cataracts, low certainty evidence suggested that combining phacoemulsification with either viscogonioplasty or goniosynechialysis does not confer any additional benefit over phacoemulsification alone. There was insufficient evidence to draw any meaningful conclusions regarding phacoemulsification versus trabeculectomy. Low certainty evidence suggested that combining phacoemulsification with trabeculectomy does not confer any additional benefit over phacoemulsification alone, and may cause more complications instead. These conclusions only apply to short- to medium-term outcomes; studies with longer follow-up periods can help assess whether these effects persist in the long term.

Laser peripheral iridoplasty for chronic angle closure

BACKGROUND

In at least a third of primary angle closure cases, appositional angle closure persists after laser peripheral iridotomy, and further intervention may be considered. Laser peripheral iridoplasty (LPIp) can be used in treating chronic angle closure when angle closure persists after laser peripheral iridotomy. Previous reviews have found insufficient data to determine its clinical effectiveness, compared to other interventions. This is an update of a Cochrane Review first published in 2008 and updated in 2012. It examines all studies to date to establish whether LPIp shows any effectiveness over other available treatment options.

OBJECTIVES

To assess the effectiveness of laser peripheral iridoplasty in the treatment of people with chronic angle closure, when compared to laser peripheral iridotomy, medical therapy or no further treatment.

SEARCH METHODS

We searched various electronic databases. The date of the search was 20 December 2020.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) assessing the use of LPIp in cases of suspected primary angle closure (PACS), confirmed primary angle closure (PAC), or primary chronic angle-closure glaucoma (PACG). We applied no restrictions with respect to gender, age or ethnicity of participants. Trials evaluating LPIp for acute attacks of angle closure were not eligible.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two authors independently assessed studies for risk of bias using Cochrane's 'risk of bias' tool. We collected adverse effects information from the trials.

MAIN RESULTS

We included four RCTs involving 252 participants (276 eyes). In total, three different methods of intervention were used and 15 outcomes reported, with different time points. We used narrative synthesis to describe the majority of the findings, as meta-analysis was only possible for a limited number of outcomes due to the variation in study design and outcomes assessed. Study Characteristics Participants were adults recruited from outpatient settings in the UK, Singapore, China and Korea with either PACS, PAC or PACG. All studies compared argon LPIp (as either a primary or secondary procedure) to an alternative intervention or no further treatment. Three studies were of parallel group design, and one within-person, randomised by eye. All studies showed elements of high risk of bias. Due to the nature of the intervention assessed, a lack of masking of both participants and assessors was noted in all trials. Findings Laser peripheral iridoplasty with iridotomy versus iridotomy alone as a primary procedure Two RCTs assessed the use of argon LPIp as a primary procedure with peripheral iridotomy, compared with peripheral iridotomy alone. However, neither study reported data for the primary outcome, disease progression. Argon LPIp showed no evidence of effect on: final mean intraocular pressure (IOP) at 3 months and 12 months (mean difference (MD) 0.39 mmHg, 95% confidence interval (CI) -1.07 to 1.85; I² = 38%; 2 studies, 174 participants; low-certainty evidence); further surgical or laser intervention at 12 months (risk ratio (RR) 1.21, 95% CI 0.66 to 2.21; 1 study, 126 participants; low-certainty evidence); or mean number of additional medications required at 12 months (MD 0.10, 95% CI -0.34 to 0.54; 1 study, 126 participants; low-certainty evidence). Complications were assessed at 3 to 12 months (2 studies, 206 participants; low-certainty evidence) and found to be mild and uncommon, with comparable levels between groups. The only severe complication encountered was one case of malignant glaucoma in one study's argon LPIp group. Quality of life measures were not assessed. In the other study, investigators found that argon LPIp showed no evidence of effect on final mean anterior segment optical coherence tomography (AS-OCT) measurements, including anterior chamber depth (MD 0.00 mm, 95% CI -0.10 to 0.10; 24 participants, 48 eyes; very low-certainty evidence). Laser peripheral iridoplasty as a secondary procedure versus no treatment One RCT assessed the use of argon LPIp as a secondary procedure compared with no further treatment in 22 participants over three months. Disease progression, additional medications required, complications, further surgical or laser intervention, and quality of life outcomes were not assessed. There was only very low-certainty evidence regarding final maximum IOP value (MD -1.81 mmHg, 95% CI -3.11 to -0.51; very low-certainty evidence), with no evidence of effect on final minimum IOP values (MD -0.31 mmHg, 95% CI -1.93 to 1.31; very low-certainty evidence). The evidence is very uncertain about the effect of argon LPIp on AS-OCT parameters. The trial did not report AS-OCT measurements for the control group. Laser peripheral iridoplasty as a secondary procedure versus medication One RCT assessed the use of argon LPIp as a secondary procedure compared with travoprost 0.004% in 80 participants over 12 months. The primary outcome of disease progression was reported for this method: argon LPIp showed no evidence of effect on mean final cup/disk ratio (MD -0.03, 95% CI -0.11 to 0.05; low-certainty evidence). Argon LPIp showed no evidence of effect for: mean change in IOP (MD -1.20 mmHg, 95% CI -2.87 to 0.47; low-certainty evidence) or mean number of additional medications (MD 0.42, 95% CI 0.23 to 0.61; low-certainty evidence). Further surgical intervention was required by one participant in the intervention group alone, with none in the control group  (low-certainty evidence). No serious adverse events were reported, with mild complications consisting of two cases of 'post-laser IOP spike' in the argon LPIp group. Quality of life measures were not assessed. The evidence is very uncertain about the effect of argon LPIp on AS-OCT parameters. The trial did not report AS-OCT measurements for the control group. Adverse events Availability of data were limited for adverse effects. Similar rates were observed in control and intervention groups, where reported. Serious adverse events were rare.

AUTHORS' CONCLUSIONS

After reviewing the outcomes of four RCTs, argon LPIp as an intervention may be no more clinically effective than comparators in the management of people with chronic angle closure. Despite a potential positive impact on anterior chamber morphology, its use in clinical practice in treating people with chronic angle closure is not supported by the results of trials published to date. Given these results, further research into LPIp is unlikely to be worthwhile.

Updates on Genes and Genetic Mechanisms Implicated in Primary Angle-Closure Glaucoma

Primary angle-closure glaucoma (PACG) is estimated to affect over 30 million people worldwide by 2040 and is highly prevalent in the Asian population. PACG is more severe and carries three times the higher risk of blindness than primary open-angle glaucoma, thus representing a significant public health concern. High heritability and ethnic-specific predisposition to PACG suggest the involvement of genetic factors in disease development. In the recent past, genetic studies have led to the successful identification of several genes and loci associated with PACG across different ethnicities. The precise cellular and molecular roles of these multiple loci in the development and progression of PACG remains to be elucidated. Nonetheless, these studies have significantly increased our understanding of the emerging cellular processes and biological pathways that might provide more significant insights into the disease’s genetic etiology and may be valuable for future clinical applications. This review aims to summarize and update the current knowledge of PACG genetics analysis research.

Effect of Pharmacological Pupil Dilatation on Angle Configuration in Untreated Primary Angle Closure Suspects: A Swept Source Anterior Segment Optical Coherence Tomography Study

PRECIS

Angle-closure worsens with pharmacological dilatation in about 50.0% of the subjects diagnosed as primary angle-closure suspects (PACSs).

PURPOSE

The purpose of this study was to evaluate the changes in angle configuration with swept-source anterior segment optical coherence tomography before and after pharmacological pupil dilatation in untreated PACSs.

PATIENTS AND METHODS

A total of 106 subjects over the age of 50 years and diagnosed as PACSs were included in this cross-sectional cohort study. 360-degree scans of the angles were captured using swept-source optical coherence tomography before and 1 hour after pharmacological dilatation. The angle scans from swept-source optical coherence tomography were analyzed to calculate the iris-trabecular contact (ITC) index. The main outcome measure was to evaluate the change in ITC index after dilatation. Multivariate linear and logistic regression analysis were performed to identify factors influencing change of ITC index and to identify factors associated with increase in ITC index after dilatation.

RESULTS

Majority of subjects were Chinese (93.4%) and female (79.2%). The overall mean predilatation ITC index was 45.3% (±23.7) and postdilatation ITC index was 46.05% (±25.9) with a mean change of 0.78% (±16.5; P=0.62). Fifty-three eyes (50.0%) showed an increase in ITC index (angle narrowing) after dilatation. An increase in ITC index was associated with shallower anterior chamber depth (odds ratio: 0.18; 95% confidence interval: 0.04-0.77) and bigger lens vault (odds ratio: 14.31; 95% confidence interval: 1.55-132.34).

CONCLUSIONS

Pharmacological pupil dilatation worsened angle closure in 50.0% of subjects with narrow angles. Shallower anterior chamber and bigger lens vault were associated with greater angle narrowing in these subjects.

Changes in Intraocular Pressure and Angle Structure after Dilation in Primary Angle-Closure Suspects with Visually Significant Cataract

PURPOSE

To evaluate the safety of pupillary dilation in primary angle-closure suspects (PACS) with concurrent visually significant cataract (VSC), to identify risk factors associated with elevated intraocular pressure (IOP), and to describe changes in anterior segment anatomy after pupillary dilation.

DESIGN

Prospective study.

PARTICIPANTS

Patients with PACS and VSC and no prior laser or intraocular surgery were recruited. Visually significant cataract was defined as best-corrected visual acuity ≤ 20/40 due to cataract.

METHODS

Subjects' eyes were dilated with 0.5% tropicamide and 0.5% phenylephrine hydrochloride. A standardized eye examination, biometry, and swept-source OCT (SS-OCT) were performed before dilation. Intraocular pressure and SS-OCT were repeated 1, 4, and 6 hours postdilation (PDH1, PDH4, and PDH6, respectively). All parameters were compared between time points before and after dilation using paired t test. Linear regression models were used to determine the risk factors associated with postdilation IOP changes.

MAIN OUTCOME MEASURES

Change in IOP and SS-OCT parameters from baseline.

RESULTS

Seventy-eight eyes from 78 patients were included, with 78, 66, and 12 patients completing the study at PDH1, PDH4, and PDH6, respectively. Mean IOP increased from 14.8 ± 2.6 mmHg at baseline to 15.5 ± 3.5 mmHg at PDH1 (P = 0.03) and decreased to 14.9 ± 3.1 mmHg at PDH4 (P = 0.09). Four patients (5.13%) and 3 patients (3.85%) had an increase in IOP ≥ 5 mmHg at PDH1 and PDH4, respectively. Two patients (2.56%) and 1 patient (1.28%) had an increase in IOP ≥ 8 mmHg at PDH1 and PDH4, respectively. None developed acute primary angle-closure during the observation period. Almost all anterior chamber parameters showed a significant increase after dilation at PDH1 and PDH4, except lens vault and iris volume, which decreased at PDH1 and PDH4 from baseline. Increase in anterior chamber depth was negatively associated with the level of IOP elevation after dilation (P < 0.01).

CONCLUSIONS

Dilation of patients' eyes with PACS and VSC in this cohort appears to have a low risk for IOP spike. This may be associated with relaxation of the ciliary muscle leading to posterior displacement of the lens-iris diaphragm and deepening of the anterior chamber.

Non-contact tests for identifying people at risk of primary angle closure glaucoma

BACKGROUND

Primary angle closure glaucoma (PACG) accounts for 50% of glaucoma blindness worldwide. More than three-quarters of individuals with PACG reside in Asia. In these populations, PACG often develops insidiously leading to chronically raised intraocular pressure and optic nerve damage, which is often asymptomatic. Non-contact tests to identify people at risk of angle closure are relatively quick and can be carried out by appropriately trained healthcare professionals or technicians as a triage test. If the test is positive, the person will be referred for further specialist assessment.

OBJECTIVES

To determine the diagnostic accuracy of non-contact tests (limbal anterior chamber depth (LACD) (van Herick test); oblique flashlight test; scanning peripheral anterior chamber depth analyser (SPAC), Scheimpflug photography; anterior segment optical coherence tomography (AS-OCT), for identifying people with an occludable angle.

SEARCH METHODS

We searched the following bibliographic databases 3 October 2019: CENTRAL; MEDLINE; Embase; BIOSIS; OpenGrey; ARIF and clinical trials registries. The searches were limited to remove case reports. There were no date or language restrictions in the searches.

SELECTION CRITERIA

We included prospective and retrospective cross-sectional, cohort and case-control studies conducted in any setting that evaluated the accuracy of one or more index tests for identifying people with an occludable angle compared to a gonioscopic reference standard.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and quality assessment using QUADAS2 for each study. For each test, 2 x 2 tables were constructed and sensitivity and specificity were calculated. When four or more studies provided data at fixed thresholds for each test, we fitted a bivariate model using the METADAS macro in SAS to calculate pooled point estimates for sensitivity and specificity. For comparisons between index tests and subgroups, we performed a likelihood ratio test comparing the model with and without the covariate.

MAIN RESULTS

We included 47 studies involving 26,151 participants and analysing data from 23,440. Most studies were conducted in Asia (36, 76.6%). Twenty-seven studies assessed AS-OCT (analysing 15,580 participants), 17 studies LACD (7385 participants), nine studies Scheimpflug photography (1616 participants), six studies SPAC (5239 participants) and five studies evaluated the oblique flashlight test (998 participants). Regarding study quality, 36 of the included studies (76.6%) were judged to have a high risk of bias in at least one domain.The use of a case-control design (13 studies) or inappropriate exclusions (6 studies) raised patient selection concerns in 40.4% of studies and concerns in the index test domain in 59.6% of studies were due to lack of masking or post-hoc determination of optimal thresholds. Among studies that did not use a case-control design, 16 studies (20,599 participants) were conducted in a primary care/community setting and 18 studies (2590 participants) in secondary care settings, of which 15 investigated LACD. Summary estimates were calculated for commonly reported parameters and thresholds for each test; LACD ≤ 25% (16 studies, 7540 eyes): sensitivity 0.83 (95% confidence interval (CI) 0.74, 0.90), specificity 0.88 (95% CI 0.84, 0.92) (moderate-certainty); flashlight (grade1) (5 studies, 1188 eyes): sensitivity 0.51 (95% CI 0.25, 0.76), specificity 0.92 (95% CI 0.70, 0.98) (low-certainty); SPAC (≤ 5 and/or S or P) (4 studies, 4677 eyes): sensitivity 0.83 (95% CI 0.70, 0.91), specificity 0.78 (95% CI 0.70, 0.83) (moderate-certainty); Scheimpflug photography (central ACD) (9 studies, 1698 eyes): sensitivity 0.92 (95% CI 0.84, 0.96), specificity 0.86 (95% CI 0.76, 0.93) (moderate-certainty); AS-OCT (subjective opinion of occludability) (13 studies, 9242 eyes): sensitivity 0.85 (95% CI 0.76, 0.91); specificity 0.71 (95% CI 0.62, 0.78) (moderate-certainty). For comparisons of sensitivity and specificity between index tests we used LACD (≤ 25%) as the reference category. The flashlight test (grade 1 threshold) showed a statistically significant lower sensitivity than LACD (≤ 25%), whereas AS-OCT (subjective judgement) had a statistically significant lower specificity. There were no statistically significant differences for the other index test comparisons. A subgroup analysis was conducted for LACD (≤ 25%), comparing community (7 studies, 14.4% prevalence) vs secondary care (7 studies, 42% prevalence) settings. We found no evidence of a statistically significant difference in test performance according to setting. Performing LACD on 1000 people at risk of angle closure with a prevalence of occludable angles of 10%, LACD would miss about 17 cases out of the 100 with occludable angles and incorrectly classify 108 out of 900 without angle closure.

AUTHORS' CONCLUSIONS

The finding that LACD performed as well as index tests that use sophisticated imaging technologies, confirms the potential for this test for case-detection of occludable angles in high-risk populations. However, methodological issues across studies may have led to our estimates of test accuracy being higher than would be expected in standard clinical practice. There is still a need for high-quality studies to evaluate the performance of non-invasive tests for angle assessment in both community-based and secondary care settings.

Measurement of Retinal Changes in Primary Acute Angle Closure Glaucoma under Different Durations of Symptoms

Purpose

To investigate the changes of retinal nerve fiber layer (RNFL) in patients after an attack of primary acute angle closure glaucoma (PAACG) and to assess the impact of attack time on prognosis of retinal changes.

Design

cross-sectional study.

Methods

Twenty-six patients with unilateral PAACG attack and cataracts from 2017 to 2019 were enrolled. Eyes with PAACG attack time less than 1 day constituted the group A (n = 13), while eyes with PAACG attack time more than 1 day constituted the group B (n = 13). All patients received phacoemulsification and viscogoniosynechialysis after intraocular pressure (IOP) lowering. All patients underwent ophthalmic examinations including IOP, best-corrected visual acuity (BCVA), and visual field (VF). Optical coherence tomography angiography (OCTA) was used to obtain circumpapillary RNFL vessel density (cpVD). Spectral domain optical coherence tomography (SD-OCT) was used to examine the peripapillary RNFL and macular ganglion cell complex (GCC). All patients accepted 2 assessments before and 1 month after the procedure.

Results

The IOP of all patients recovered to normal (12.77 ± 2.65 mm Hgvs. 12.77 ± 3.85 mmHg, p=0.834) after the procedure. Patients in the group A had better BCVA improvement than those in the group B (1.32 ± 0.84 vs. 0.50 ± 0.21, p=0.004), as well as better mean defect (MD) values from VF (-3.65 ± 2.54 vs -16.05 ± 5.99, p < 0.001). Compared with group B, patients in the group A had thicker macula (Fovea area: 255.00 ± 27.94 μm vs. 203.92 ± 59.73 μm, p=0.010), thicker GCC (82.62 ± 8.76 μm vs. 65.23 ± 18.56 μm, p=0.005), and thicker RNFL (105.08 ± 9.38 μm vs. 77.69 ± 20.23 μm, p < 0.001). Higher blood flow density in all-plexus peripapillary retina was observed in the group A eyes compared with group B (full sector: 0.56 ± 0.02 vs. 0.41 ± 0.07, p < 0.001). In both groups, the association between average RNFL thickness and cpVD as well as MD values and pattern standard deviation (PSD) values from VF was stronger (R ² = 0.58, 0.60, -0.54, respectively, all p < 0.001) than the association between GCC thickness and cpVD, as well as MD values and PSD values (R ² = 0.37, p=0.001; R ² = 0.37, p=0.001; R ² = -0.27, p=0.007).

Conclusion

Patients with attack time less than 1 day had better retinal thickness and all-plexus peripapillary retina blood flow density. Controlling the attack time could decrease retinal damage by PAACG.

Cataract, phacoemulsification and intraocular pressure: Is the anterior segment anatomy the missing piece of the puzzle?

Cataract extraction is a safe and effective surgery that has a lowering effect on the intraocular pressure. The specific mechanisms for this effect are still unclear. A direct inflammatory effect on the trabecular meshwork, alteration of the blood aqueous barrier, changes in the ciliary body and mechanical changes of the anterior segment anatomy are the key to understand cataract surgery and it's effects on aqueous humor dynamics. Additionally, with the advent of AS OCT, changes in the anterior segment of the eye have been studied and several parameters (such as lens vault, angle opening distance and anterior chamber depth) have been identified as predictors of intraocular pressure change. In eyes with narrow angles there is a greater drop in intraocular pressure after cataract surgery and it is correlated with parameters related to anterior chamber space. It is safe to affirm that cataract surgery is an important part of the modern glaucoma treatment and evidence should be analyzed as part of a bigger picture in order to more accurately understand its clinical relevance.

Spectrum of Angle Closure, Uveal Effusion Syndrome, and Nanophthalmos

Nanophthalmos, uveal effusion syndrome, and acute angle closure glaucoma (ACG) can present as a continuum in a patient, as is described here. This patient's angle closure was thought to be caused by idiopathic uveal effusion syndrome, and while there are no generally accepted diagnosis criteria for nanophthalmos, our patient fulfilled the criteria as defined by Wu.¹⁰ To prevent development of further angle closure, the decision was made to do cataract extraction as opposed to medical management.

Genetic associations in PLEKHA7 and COL11A1 with primary angle closure glaucoma: a meta-analysis

BACKGROUND

Single nucleotide polymorphisms (SNPs) rs11024102 in PLEKHA7 and rs3753841 in COL11A1 were identified to be associated with primary angle closure glaucoma (PACG) by a recent large genome-wide association study. This present study is to evaluate the association of PLEKHA7 rs11024102 and COL11A1 rs3753841 with PACG.

DESIGN

A systematic review and meta-analysis.

PARTICIPANTS

A total of 25 271 subjects (4895 PACG patients and 20 376 controls) in different ethnicities were tested for PLEKHA7 rs11024102 and COL11A1 rs3753841.

METHODS

A comprehensive literature search was conducted on studies published up to July 2014. Summary odds ratios (ORs) and 95% confidence intervals were analysed. Publication bias of the included articles was evaluated using funnel plots and Egger's test.

MAIN OUTCOME MEASURES

OR for the effects of PLEKHA7 rs11024102 and COL11A1 rs3753841 on PACG risk.

RESULTS

Four eligible articles were included in this study for meta-analysis. The overall result showed that SNPs rs11024102 and rs3753841 were statistically associated with PACG (P < 0.001) in fixed-effects model. Stratified analyses showed that the association of PLEKHA7 rs11024102 and COL11A1 rs3753841 with PACG was statistically significant in Asian population (including South Indian cohort) (P < 0.001). In Caucasian population, significant association of COL11A1 rs3753841 with PACG was detected (P = 0.004), but PLEKHA7 rs11024102 did not show any association with PACG (P = 0.140).

CONCLUSIONS

This meta-analysis suggests that PLEKHA7 rs11024102 is associated with PACG in Asian population and COL11A1 rs3753841 has a genetic association with the development of PACG both in Caucasian and Asian populations.

A Study on the Central Corneal Thickness of Primary Angle Closure and Primary Angle Closure Glaucoma and Its Effect on Visual Field Progression

PURPOSE

To determine the mean central corneal thickness (CCT) and the relationship between the CCT and visual field progression in primary angle closure (PAC) and primary angle closure glaucoma (PACG).

DESIGN

A combined cross-sectional and prospective study on PAC and PACG.

METHODS

A total of 35 eyes were included in the study for each group of normal control, PAC, and PACG patients from eye clinics in Kota Bharu, state of Kelantan, Malaysia, from January 2007 to November 2009. The PAC and PACG patients were divided into thin and thick CCT groups. They were followed up for 12 to 18 months for visual field progression assessment with their mean Advanced Glaucoma Intervention Study (AGIS) score.

RESULTS

The CCT was 516.8 ± 26.0 µm for PAC and 509.7 ± 27.4 µm for PACG. Both were significantly thinner compared with the control group with CCT of 540 ± 27.8 µm (P < 0.001). There was a statistically significant increase in the mean AGIS score after 12.9 ± 1.7 months of follow-up in the thin CCT group for PACG (P = 0.002). However, no significant increase in the mean AGIS score was found for the thick CCT group in PACG and for both thin and thick CCT in PAC.

CONCLUSIONS

The PAC and PACG had statistically significant thinner CCT compared with the controls. Thin CCT was associated with visual field progression based on the mean AGIS score in PACG.

Primary open-angle glaucoma in a population associated with high prevalence of primary angle-closure glaucoma: the Kumejima Study

PURPOSE

To evaluate the prevalence of and risk factors for primary open-angle glaucoma (POAG) in a rural population of southwestern Japan.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

All residents 40 years of age and older in Kumejima, Okinawa, Japan.

METHODS

Of the eligible 4632 residents 40 years of age and older, 3762 subjects (participant rate, 81.2%) underwent screening examinations, including visual acuity (VA) measurement, slit-lamp examination, Goldmann applanation tonometry, gonioscopy, undilated stereoscopic fundus photographs, autorefractometry, noncontact specular microscopy, pachymetry, and visual field (VF) testing using frequency-doubling technology. If glaucoma or other related ocular disorders were suspected, subjects were referred for definitive examinations including VF testing with the Humphrey Field Analyzer. The diagnosis of POAG was based on the criteria of the International Society for Geographical and Epidemiological Ophthalmology.

MAIN OUTCOME MEASURES

Prevalence and risk factors of POAG.

RESULTS

The prevalence of POAG was 4.0% (95% confidence interval [CI], 3.4%-4.7%); 82% of patients had an intraocular pressure (IOP) less than 22 mmHg, resulting in a prevalence of 3.3% (95% CI, 2.8%-3.9%). Because of POAG, 3 subjects had a VA worse than 20/400 in only 1 eye, and 1 subject had VA loss of worse than 20/400 bilaterally. The average IOP values (mean ± standard deviation) were 14.9 ± 3.2 and 14.6 ± 3.3 mmHg in the right and left eyes, respectively; the IOP values were higher in patients with POAG (15.4 ± 3.3 and 15.2 ± 3.3 mmHg, respectively) than in subjects without glaucoma (14.8 ± 3.1 and 14.4 ± 3.1 mmHg, respectively; P<0.045, Student t test). Multivariate analysis showed that male gender (P = 0.003), older age (P<0.001), higher IOP (P<0.001), longer axial length (P<0.001), and thinner central cornea (P = 0.006) were associated with POAG.

CONCLUSIONS

High prevalence rates of POAG (4.0%) and POAG with normal IOP levels (3.3%), which were comparable with those on the Japanese mainland, were found in a southwestern rural island of Japan, where the prevalence of primary angle-closure glaucoma (previously reported as 2.2%) was considerably higher than on the Japanese mainland (0.6% in the Tajimi Study) or other countries. The risk factors for POAG included male gender, older age, higher IOP, myopia, and a thinner cornea.

Association of eNOS polymorphisms with anterior chamber depth in han chinese: jiangsu eye study

Recently, a study reported that single nucleotide polymorphisms (SNP) in endothelial nitric oxide synthase (eNOS) were associated with primary angle closure glaucoma (PACG) in Australian cohort. In this study, we aimed to investigate whether those eNOS SNPs are associated with primary angle closure (PAC) or ocular biometric characteristics such as axial length (AL), anterior chamber depth (ACD), and diopter of spherical power (DS) in Han Chinese. The samples consisted of 232 PAC subjects and 306 controls collected from a population-based prevalence survey conducted in Funing County of Jiangsu, China. The rs3793342 and rs11771443 in eNOS were genotyped by TaqMan-MGB probe using the RT-PCR system. Our data did not identify any association of the eNOS SNPs with PAC. However, the analysis on the quantitative traits of ocular biometrics showed that the ACD of rs11771443 AA and GA carriers is significantly deeper than that of rs11771443 GG carriers (P = 0.0025), even though the AL and DS are not associated with rs11771443 genotypes. Rs3793342 was not associated with any biometric parameters including ACD, AL and DS. In summary, our data indicates that eNOS rs11771443 is associated with ACD and its role in the pathogenesis of PACG warranted further study.

A prospective comparison of chronic primary angle-closure glaucoma versus primary open-angle glaucoma in Singapore

INTRODUCTION

To describe the optic disc, visual field and ocular characteristics of a consecutive cohort of Asian patients with chronic primary angle-closure glaucoma (CPACG), and compare them with those having primary open-angle glaucoma (POAG).

METHODS

In a prospective comparative case series of new patients with POAG or CPACG in Singapore, all patients underwent visual acuity assessment, slit-lamp examination, tonometry, gonioscopy, refraction, Heidelberg Retina Tomograph (HRT) and Humphrey visual field (HVF) assessment.

RESULTS

98 patients were enrolled (POAG n = 48; CPACG n = 50). CPACG patients were significantly older (66.5 ± 9.2 years vs. 64.1 ± 13.5 years; p = 0.027) and mostly female (p = 0.004). CPACG eyes had significantly higher intraocular pressure (26.9 ± 6.9 mmHg vs. 24.5 ± 3.3 mmHg; p = 0.03), shorter axial length (22.89 ± 0.97 mm vs. 24.26 ± 1.79 mm; p < 0.001) and shallower anterior chamber depth (2.60 ± 0.25 mm vs. 3.16 ± 0.48 mm; p < 0.001). HVF mean deviation or pattern standard deviation (PSD) did not differ significantly between POAG and CPACG eyes, but the latter had a lower PSD for a given mean deviation. HRT parameters between the two groups were not significantly different.

CONCLUSION

In this study, CPACG eyes had significantly higher presenting intraocular pressure than POAG eyes, but there were no significant differences in optic disc topography. A majority of the patients in both groups had moderate field defects at the time of presentation, followed by severe and then mild defects. The field loss in CPACG eyes was more diffuse than that in POAG eyes.

An extensive replication study on three new susceptibility Loci of primary angle closure glaucoma in han chinese: jiangsu eye study

Genome-wide association study (GWAS) analysis identified three new susceptibility loci for PACG. In this study, we aimed to investigate whether these three loci in PLEKHA7, COL11A1, and PCMTD1-ST18 are associated with PAC and ocular biometric characteristics, such as axial length (AL), anterior chamber depth (ACD), and diopter of spherical power (DS). The study was a part of the Jiangsu Eye Study. The samples were collected from 232 PAC subjects and 306 controls from a population-based prevalence survey conducted in Funing County of Jiangsu, China. The single nucleotide polymorphisms (SNPs) of rs11024102 in PLEKHA7, rs3753841 in COL11A1, and rs1015213 in PCMTD1-ST18 were genotyped by TaqMan-MGB probe using the RT-PCR system. None of the three polymorphisms showed differences in the distribution of genotypes and allele frequencies between the PAC group and the control group. No significant association was determined between the 3 SNPs and AL, ACD, or DS of PAC subjects. We concluded that even though PLEKHA7 rs11024102, COL11A1 rs3753841, and PCMTD1-ST18 rs1015213 are associated with PACG, those sequence variations are not associated with PAC in a Han Chinese population. Our results also did not support a significant role for these three SNPs in ocular biometry such as AL, ACD, and DS.

Association study in a South Indian population supports rs1015213 as a risk factor for primary angle closure

PURPOSE

Three loci defined by single nucleotide polymorphisms (SNPs) rs11024102 in PLEKHA7, rs3753841 in COL11A1, and rs1015213 between the PCMTD1 and ST18 genes, recently have been associated with primary angle closure glaucoma (PACG). We explored the genetic association of these SNPs with subtypes of primary angle closure in a South Indian population.

METHODS

The study included three case definitions: primary angle closure/primary angle closure glaucoma (PAC/PACG, N = 180); primary angle closure suspect (PACS, N = 171), and a combined any-angle closure group. Controls consisted of 411 individuals from South India. Genotyping for all three SNPs was performed using the TaqMan allelic discrimination assay. Genetic association was estimated using a χ(2) test statistics and logistic regression.

RESULTS

Among the three studied SNPs, significant genetic association was identified for rs1015213 in the PAC/PACG (P = 0.002) and any-angle closure (P = 0.003) analyses. However, no significant genetic association was seen when in PACS subjects (P = 0.052). SNPs rs3753841 and rs11024102 showed no evidence of genetic association with angle-closure phenotypes (P > 0.05) in South Indian participants.

CONCLUSIONS

In our study, rs1015213 (located in the intergenic region between PCMTD1 and ST18) was associated significantly with PAC/PACG, confirming prior reports of an association between this region and angle closure glaucoma. Further work with a larger sample size is necessary to confirm the importance of COL11A1 and PLEKHA7 in the pathogenesis of glaucoma.

How bioinformatics influences health informatics: usage of biomolecular sequences, expression profiles and automated microscopic image analyses for clinical needs and public health

ABSTRACT

The currently hyped expectation of personalized medicine is often associated with just achieving the information technology led integration of biomolecular sequencing, expression and histopathological bioimaging data with clinical records at the individual patients' level as if the significant biomedical conclusions would be its more or less mandatory result. It remains a sad fact that many, if not most biomolecular mechanisms that translate the human genomic information into phenotypes are not known and, thus, most of the molecular and cellular data cannot be interpreted in terms of biomedically relevant conclusions. Whereas the historical trend will certainly be into the general direction of personalized diagnostics and cures, the temperate view suggests that biomedical applications that rely either on the comparison of biomolecular sequences and/or on the already known biomolecular mechanisms have much greater chances to enter clinical practice soon. In addition to considering the general trends, we exemplarily review advances in the area of cancer biomarker discovery, in the clinically relevant characterization of patient-specific viral and bacterial pathogens (with emphasis on drug selection for influenza and enterohemorrhagic E. coli) as well as progress in the automated assessment of histopathological images. As molecular and cellular data analysis will become instrumental for achieving desirable clinical outcomes, the role of bioinformatics and computational biology approaches will dramatically grow.

AUTHOR SUMMARY

With DNA sequencing and computers becoming increasingly cheap and accessible to the layman, the idea of integrating biomolecular and clinical patient data seems to become a realistic, short-term option that will lead to patient-specific diagnostics and treatment design for many diseases such as cancer, metabolic disorders, inherited conditions, etc. These hyped expectations will fail since many, if not most biomolecular mechanisms that translate the human genomic information into phenotypes are not known yet and, thus, most of the molecular and cellular data collected will not lead to biomedically relevant conclusions. At the same time, less spectacular biomedical applications based on biomolecular sequence comparison and/or known biomolecular mechanisms have the potential to unfold enormous potential for healthcare and public health. Since the analysis of heterogeneous biomolecular data in context with clinical data will be increasingly critical, the role of bioinformatics and computational biology will grow correspondingly in this process.

Efficacy of goniosynechialysis for advanced chronic angle-closure glaucoma

Purpose:

To evaluate the intraocular pressure (IOP)-lowering efficacy of goniosynechialysis (GSL) for advanced chronic angle-closure glaucoma (CACG) using a simplified slit-lamp technique.

Patients and methods:

Patients with CACG with one severely affected eye with best-corrected visual acuity below 20/200 and a mildly or functionally unaffected fellow eye were enrolled in this study. All patients underwent ophthalmologic examinations including measurement of visual acuity, best-corrected visual acuity, and IOP; biomicroscopy; specular microscopy; fundus examination; and gonioscopy followed by anterior chamber paracentesis and GSL for nasal peripheral anterior synechiae in the eye with severe CACG.

Results:

Thirty patients (18 men, 12 women) were identified as having CACG with an initial mean IOP of 47.1 ± 6.7 mmHg (range 39–61 mmHg) in the severely affected eye. One week after GSL, the mean IOP of the treated eyes decreased to 19.3 ± 2.8 mmHg (range 14–26 mmHg) without antiglaucoma medication (average decrease 27.7 ± 6.5 mmHg; range 16–41 mmHg), which was significant (P < 0.00001) compared with baseline. After an average follow-up period of 36.6 ± 1.0 months (range 35–38 months), the mean IOP stabilized at 17.4 ± 2.2 mmHg (range 12–21 mmHg). The nasal angle recess did not close again in any one of the patients during the follow-up period. The average significant (P < 0.00001) decrease in corneal endothelial cell density in the treated eyes was 260 ± 183 cells/mm² (range 191–328 cells/mm²).

Conclusions:

Anterior chamber paracentesis and GSL lowers IOP in advanced CACG, though it may lead to mild corneal endothelial cell loss.

Prevalence of primary angle closure and primary angle-closure glaucoma in a southwestern rural population of Japan: the Kumejima Study

PURPOSE

To determine the prevalence and ocular biometry of primary angle closure (PAC) and primary angle-closure glaucoma (PACG) in a rural population in southwestern Japan.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

All residents aged 40 years or older in Kumejima, Okinawa, Japan.

INTERVENTION

Of the 4632 residents 40 years of age or older, 3762 (participation rate, 81.2%) underwent a detailed ocular examination, including measurement of the best-corrected visual acuity, slit-lamp examination, Goldmann applanation tonometry, static and dynamic gonioscopy, undilated stereoscopic optic fundus photographs, autorefractometry, partial coherence laser interferometry, noncontact specular microscopy, and screening visual field (VF) testing using frequency-doubling technology. If glaucoma or related or other ocular disorders were suspected, the subject was referred for a definitive examination including VF testing with the 24-2 Swedish Interactive Thresholding Algorithm Standard program of the Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA).

MAIN OUTCOME MEASURES

Prevalence rates of primary angle-closure suspects (PACS), PAC, PACG, and PACG suspects.

RESULTS

Under the standard definitions of the International Society of Geographical and Epidemiological Ophthalmology, the prevalence rates of PACS, PAC, and PACG were 8.8%, 3.7%, and 2.0%. Extending the diagnosis of PAC and PACG to include people with narrow but open angles and primary peripheral anterior synechiae, the prevalence rates of PAC and PACG increased to 6.0% and 2.2%, respectively. Hence, broadening the diagnostic categories in PAC and PACG increased the prevalence rates by 62% and 10%. Twenty-three subjects (0.6%; 95% confidence interval, 0.4%-0.9%) had a history of or were diagnosed with acute PAC. Older age, female gender, hyperopic refractive error, short axial length, and shallow anterior chamber depth were independent predictors of an occludable angle.

CONCLUSIONS

The prevalence of PACG in Kumejima (2.2%) was one of the highest reported in population-based studies, that is, 3.7 times higher than in the Tajimi Study carried out in an urban center located in the central area of the main island of Japan.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Relationship between relative lens position and appositional closure in eyes with narrow angles

PURPOSE

To investigate the relationship between relative lens position (RLP) and appositional closure in eyes with narrow angles.

METHODS

Ultrasound biomicroscopy (UBM) was used to measure anterior chamber depth (ACD) and lens thickness (LT), and the IOLMaster to measure axial length (AL). The number of quadrants with appositional closure was assessed by UBM under dark conditions. The RLP was calculated thus: RLP = 10 × (ACD + 0.5 LT) /AL.

RESULTS

This study comprised 30 consecutive patients (30 eyes) with narrow-angle eyes defined as Shaffer grade 2 or lower and without peripheral anterior synechiae (24 women, 6 men; mean age ± SD, 67.3 ± 10.4 years; range, 42-87 years). Under dark conditions, 66.7% of the eyes with narrow angles showed appositional closure in at least one quadrant. Of the various ocular biometric parameters, only the RLP significantly decreased with appositional closure in at least one quadrant (P = 0.005).

CONCLUSION

A decrease in the RLP can be predictive of appositional closure for narrow-angle eyes under dark conditions.

Gender and glaucoma: what we know and what we need to know

PURPOSE OF REVIEW

With growing aging populations and an increase in cases of glaucoma and glaucoma blindness worldwide, aging populations are particularly at higher risk of glaucoma and glaucoma blindness. Awareness of the gender differences might increase attention toward populations at risk.

RECENT FINDINGS

Women not only outlive men, but also outnumber men in glaucoma cases worldwide. Women are at higher risks for angle closure glaucoma, but there is no clear gender predilection for open angle glaucoma. Of interest, there is some evidence suggesting that female sex hormones might be protective of the optic nerve. In addition, it is hypothesized that decreased estrogen exposure is associated with increased risk for open angle glaucoma, yet population-based studies present inconsistent results. Presently, there is insufficient evidence to support hormonal replacement therapy use in glaucoma prevention. In addition, it appears that women carry a larger burden of glaucoma blindness due to longevity and disadvantages in socioeconomic/health beliefs.

SUMMARY

Current evidence suggests that older women are at risk for glaucoma and glaucoma blindness. Further interdisciplinary research involving investigators, specialized in glaucoma, women's health and health disparities, will lead to better understanding of gender health disparities in glaucoma and better targeting populations at risk.

Pharmacological and environmental factors in primary angle-closure glaucoma

INTRODUCTION OR BACKGROUND

A large number of drug classes have now been reported to provoke angle closure in high-risk individuals. The mechanism of action can be generalized into three main categories: sympathomimetic, parasympatholytic and idiosyndratic reactions.

SOURCES OF DATA

This review of the ophthalmic literature provides a clinical summary of primary angle-closure glaucoma (PACG) and its management.

AREAS OF AGREEMENT

External stimuli (pharmacological and environmental) may induce acute, and more often, asymptomatic angle closure, which carries a significant risk of glaucoma.

GROWING POINTS

Whenever in doubt, patients at risk of PACG who are starting on drug therapy known to provoke angle closure or aggravate the condition should be referred for detailed gonioscopic examination of the anterior chamber by an ophthalmologist. AREAS FOR DEVELOPING RESEARCH: The use of new imaging methods such as anterior segment optical coherence tomography to assess the presence or risk of angle closure is gaining popularity, and may offer a more rapid method of identifying people who are at risk of sight loss from angle-closure glaucoma precipitated by non-ophthalmological medication.