Identification of eyes at risk of acute primary angle-closure in elderly Japanese patients

Characteristics of optic disc hemorrhage and optic nerve changes following acute primary angle closure

Introduction

Acute primary angle closure (APAC) is an emergency ophthalmic presentation and a major cause of irreversible blindness in China. However, only a few studies have focused on the characteristics of optic disc hemorrhage (ODH) during an APAC attack, including its shape, depth, location, scope, and duration after intraocular pressure (IOP) control, along with changes in the optic nerve. This study aimed to analyze the characteristics of ODH and optic nerve changes in patients during their first APAC episode.

Methods

This retrospective study involved 32 eyes from 32 patients with APAC who received sequential treatment and analyzed the following parameters: the highest IOP and its duration, ODH, retinal nerve fiber layer thickness (RNFLT), and mean deviation (MD). We compared parameters obtained from the affected eye (ODH group) and contralateral unaffected eye (control group), as well as intragroup comparisons.

Results

The mean IOP in the ODH group was 64.28 ± 10.36 mmHg, with a duration of 4.44 ± 2.35 days. Flame and splinter shapes accounted for 84.38% of the ODH. The mean ODH duration was 4.81 ± 3.25 weeks. ODH during APAC was isolated to one sector in 59.38% of cases, mostly occurring in the temporal superior and temporal inferior (each accounting for 21.88% of the cases). There was a positive correlation between the extent of hemorrhage and the highest IOP duration (p < 0.001). RNFLT was significantly thickened within 72 h post-IOP control but was thinned by 2 weeks. By 6 months, the thinning stabilized, and there was no difference noted between the ODH and control groups at 12 months. MD partly improved at 6 months post-IOP control, and ODH scope significantly affected the MD (p < 0.001). The duration of high IOP was positively correlated to the ODH scope and MD damage.

Discussion

Timely and effective IOP management is essential for recovering visual function following an APAC attack.

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.