-
The Cochrane Database of Systematic... May 2020Primary angle closure glaucoma (PACG) accounts for 50% of glaucoma blindness worldwide. More than three-quarters of individuals with PACG reside in Asia. In these... (Meta-Analysis)
Meta-Analysis
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.
Topics: Anterior Chamber; Bias; Case-Control Studies; Confidence Intervals; Diagnostic Techniques, Ophthalmological; Glaucoma, Angle-Closure; Gonioscopy; Humans; Patient Selection; Photography; Prospective Studies; Reference Standards; Retrospective Studies; Sensitivity and Specificity; Tomography, Optical Coherence; Triage
PubMed: 32468576
DOI: 10.1002/14651858.CD012947.pub2 -
Medicine Oct 2019The aim of this meta-analysis is to compare the efficacy and safety of combined phacoemulsification (Phaco) with goniosynechialysis (GSL) to either Phaco or to Phaco... (Meta-Analysis)
Meta-Analysis
Systematic Review and Meta-Analysis of Comparing Phacoemulsification Combined with goniosynechialysis to other mainstream procedures in treating patients with angle-closure glaucoma.
BACKGROUND
The aim of this meta-analysis is to compare the efficacy and safety of combined phacoemulsification (Phaco) with goniosynechialysis (GSL) to either Phaco or to Phaco combined with trabeculectomy or trabeculectomy alone in patients with angle closure glaucoma (ACG).
METHODS
Five main electronic databases were searched for the eligible studies. Intraocular pressure (IOP) decrease was set as the primary outcome, while anti-glaucomatous medication decrease, changes of anterior chamber depth (ACD), range of peripheral anterior synechia (PAS), and complication occurrence were the secondary outcomes. Standard mean difference (SMD) and relative risk (RR) were the size effects for continuous and binomial data, respectively. Either fixed-effects model or random-effects model was chosen to pool the data based on the heterogeneities.
RESULTS
A total of 7 eligible studies were included. The combined data showed the IOP decreased more significantly after Phaco-GSL than that after Phaco alone (SMD = -0.42,95%CI: -0.70 - 0.14, I = 17.6%, Z = 2.90, P = .004). However, there were no distinct differences regarding medication decrease (SMD = -0.25,95%CI: -0.70 - 0.21, I = 0%, Z = 1.06, P = 0.29), ACD, the range of PAS and complication occurrence rate when compared Phaco-GSL to Phaco. Moreover, Phaco-GSL was comparable to Phaco-trabeculectomy/trabeculectomy in decreasing IOP (SMD = -0.08, 95%CI = -0.32 - 0.15, I = 0%, Z = 0.70, P = .49).
CONCLUSIONS
Phaco-GSL might be an optimal procedure to treat ACG with concomitant cataract due to its bleb-less nature, and its capacity for lowering IOP seems superior to Phaco alone and comparable to Phaco-trabeculectomy/trabeculectomy.
Topics: Cataract; Ciliary Body; Glaucoma, Angle-Closure; Humans; Intraocular Pressure; Phacoemulsification; Trabeculectomy; Visual Acuity
PubMed: 31626152
DOI: 10.1097/MD.0000000000017654 -
BMJ Open Ophthalmology 2019Plateau iris syndrome (PIS) is a frequent cause of angle closure. Argon laser peripheral iridoplasty (ALPI) has been proposed in PIS to widen the iridocorneal angle. The...
Plateau iris syndrome (PIS) is a frequent cause of angle closure. Argon laser peripheral iridoplasty (ALPI) has been proposed in PIS to widen the iridocorneal angle. The objective of the present study was to perform a systematic review of the available studies evaluating the efficacy of ALPI on intraocular pressure (IOP), iridocorneal angle opening and the number of medications in patients with chronic angle-closure associated with PIS. One prospective and seven retrospective studies with a minimum 1 month of follow-up were included. Although ALPI seemed to lower IOP, to decrease the number of topical antiglaucoma medications and widen the iridocorneal angle shortly after the procedure, there is no current evidence of long-term efficacy. To date, there is no robust scientific evidence to advocate ALPI as a treatment for chronic angle-closure caused by PIS.
PubMed: 31592025
DOI: 10.1136/bmjophth-2019-000340 -
Survey of Ophthalmology 2019We have systematically extracted all available heritability (h) estimates of glaucoma and related endophenotypes from the literature and summarized the evidence by... (Meta-Analysis)
Meta-Analysis
We have systematically extracted all available heritability (h) estimates of glaucoma and related endophenotypes from the literature and summarized the evidence by meta-analysis. Glaucoma endophenotypes were classified into 10 clusters: intraocular pressure, anterior chamber size, central corneal thickness, cup-to-disc ratio, disc size, cup size, corneal hysteresis, retinal nerve fiber layer thickness, cup shape, and peripapillary atrophy. Random-effects meta-analyses were performed for each cluster. For clusters with n ≥ 10 h estimates, we also performed subgroup and meta-regression analyses. The literature search yielded 53 studies. The h of primary open-angle glaucoma ranged from 0.17 to 0.81, and was 0.65 for primary angle-closure glaucoma in a single study. The pooled endophenotype h estimates were intraocular pressure, 0.43 (0.38-0.48); anterior chamber size, 0.67 (0.60-0.74); central corneal thickness, 0.81 (0.73-0.87); cup-to-disc ratio, 0.56 (0.44-0.68); disc size, 0.61 (0.37-0.81); cup size, 0.58 (0.35-0.78); corneal hysteresis, 0.40 (0.29-0.51); retinal nerve fiber layer thickness, 0.73 (0.42-0.91); cup shape, 0.62 (0.22-0.90); and peripapillary atrophy, 0.73 (0.70-0.75). We identified mean age, ethnicity, and study design as major sources of heterogeneity. Our results confirm the strong influence of genetic factors on glaucoma and its endophenotypes. These pooled h estimates provide the most accurate assessment to date of the total genetic variation that can ultimately be explained by gene-finding studies.
Topics: Genetic Predisposition to Disease; Glaucoma; Humans; Phenotype; Quantitative Trait, Heritable
PubMed: 31229521
DOI: 10.1016/j.survophthal.2019.06.002 -
The British Journal of Ophthalmology Nov 2019Compared with current imaging methods, the diagnostic performance and the advantages and limitations of optical coherence tomography angiography (OCTA) remain unclear.... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Compared with current imaging methods, the diagnostic performance and the advantages and limitations of optical coherence tomography angiography (OCTA) remain unclear. We performed a systematic review and meta-analysis of studies investigating vessel density (VD) in patients with glaucoma using OCTA.
METHODS
We conducted a literature search on PubMed, Scopus, Web of Science, ISI Conference Proceedings and Google Scholar, along with a manual search, from January 2006 to March 2018. We included prospective studies that used OCTA to compare the VD in glaucomatous eyes with healthy control eyes.
RESULTS
Of 3045 screened articles, 24 were included in a broad characterisation and 18 in the meta-analysis. We observed a statistically significant reduction in the mean peripapillary VD (MPVD) in glaucoma (MPVD: 57.53%, 95% CI 52.60 to 62.46, p< 0.001) compared with controls (MPVD: 65.47%, 95% CI 59.82 to 71.11; standardised mean difference [SMD], -1.41, 95% CI -1.62 to -1.20, p< 0.001) for 888 glaucomatous and 475 healthy eyes, and also in the mean-whole optic nerve image VD (SMD, -9.63, 95% CI -10.22 to -9.03, p<0.001), mean inside-disc VD (SMD, - 9.51, 95% CI -12.66 to -6.36, p<0.05) and mean parafoveal VD (SMD, -3.92, 95% CI -4.73 to -3.12, p<0.001). Subgroup analyses revealed a significant difference in the MPVD across glaucoma subtypes and OCTA devices.
CONCLUSION
This suggests the diagnostic utility of OCTA in detecting glaucomatous eyes; however, further longitudinal prospective studies are welcomed to characterise vascular changes in glaucoma.
Topics: Female; Fluorescein Angiography; Glaucoma, Angle-Closure; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Low Tension Glaucoma; Male; Nerve Fibers; Optic Disk; Prospective Studies; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 30728123
DOI: 10.1136/bjophthalmol-2018-313461