Risk Factors Associated with Missed Diagnoses of Narrow Angles by the Van Herick Technique

Practice Patterns and Sociodemographic Disparities in the Clinical Care of Anatomical Narrow Angles in the United States

PURPOSE

To assess treatment and visit patterns among patients with newly diagnosed anatomical narrow angle (ANA) and identify sociodemographic factors associated with disparities in care.

DESIGN

Retrospective practice pattern evaluation study.

METHODS

A total of 263,422 patients diagnosed with ANA between 2007 and 2019 were identified in the Optum Clinformatics Data Mart. Inclusion was limited to newly diagnosed ANA, defined as (1) continuous enrollment during a 2-year lookback period and 1-year study period from first diagnosis; (2) diagnosis by an ophthalmologist or optometrist; and (3) no history of pseudophakia, ANA treatments, or prior primary angle closure glaucoma diagnosis. Outcome measures were treatment with laser peripheral iridotomy (LPI), cataract surgery, or intraocular pressure-lowering medications and number of eye care visits. Logistic and Poisson regression were performed to assess factors associated with treatment and eye care visits, respectively.

RESULTS

Among 52,405 eligible cases, 27.7% received LPI, 13.9% received drops, and 15.1% received cataract surgery. Odds of LPI were higher in Asians and Hispanics (odds ratio [OR] ≥ 1.16, P < .001). Non-Whites had higher odds of drops (OR ≥ 1.19, P < .001), but Hispanics had lower odds of cataract surgery (OR = 0.79, P < .001). The mean number of eye care visits was 2.6±2.1 including the day of diagnosis. Older age and treatment were associated with higher rates of eye care visits (rate ratio > 1.15, P < .001).

CONCLUSION

More than a quarter of patients with newly diagnosed ANA receive treatment with LPI. Racial minorities are more likely to receive ANA-specific treatments but less likely to receive cataract surgery. These differences may reflect racial differences in disease severity and the need for clearer practice guidelines in ANA care.

Prevalence and Risk Factors of Blindness Among Primary Angle Closure Glaucoma Patients in the United States: An IRIS Registry Analysis

PURPOSE

To assess the prevalence and risk factors of blindness among patients newly diagnosed with primary angle closure glaucoma (PACG) in the United States.

DESIGN

Retrospective cross-sectional study.

METHODS

Eligible patients from the American Academy of Ophthalmology (AAO) Intelligent Research in Sight (IRIS) Registry had newly diagnosed PACG, defined as: 1) observable during a 24-month lookback period from index date of PACG diagnosis; 2) no history of eye drops, laser, or cataract surgery unless preceded by a diagnosis of anatomical narrow angle (ANA); and 3) no history of glaucoma surgery. Logistic regression models were developed to identify risk factors for any (one or both eyes) or bilateral (both eyes) blindness (visual acuity ≤20/200) at first diagnosis of PACG.

RESULTS

Among 43,901 eligible patients, overall prevalence of any and bilateral blindness were 11.5% and 1.8%, respectively. Black and Hispanic patients were at higher risk of any (odds ratios [ORs] 1.42 and 1.21, respectively; P < .001) and bilateral (ORs 2.04 and 1.53, respectively; P < .001) blindness compared with non-Hispanic White patients adjusted for ocular comorbidities. Age <50 or >80 years, male sex, Medicaid or Medicare insurance product, and Southern or Western practice region also conferred a higher risk of blindness (OR > 1.28; P ≤ .01).

CONCLUSIONS

Blindness affects 1 of 9 patients with newly diagnosed PACG in the IRIS Registry. Black and Hispanic patients and Medicaid and Medicare recipients are at significantly higher risk. These findings highlight the severe ocular morbidity among patients with PACG and the need for improved disease awareness and detection methods.

Rates and Patterns of Diagnostic Conversion from Anatomical Narrow Angle to Primary Angle-Closure Glaucoma in the United States

PURPOSE

To assess rates of diagnostic conversion from anatomical narrow angle (ANA) to primary angle-closure glaucoma (PACG) in the United States and identify factors associated with diagnostic conversion.

DESIGN

Retrospective case-control study.

PARTICIPANTS

Patients diagnosed with ANA between the years 2007 and 2019 were identified based on International Classification of Diseases (ICD) codes in the Optum Clinformatics Data Mart Database. Inclusion was limited to newly diagnosed ANA, defined as the following: (1) continuous enrollment during a 2-year look back period and 6-year study period from index (first) date of ANA diagnosis; (2) diagnosis by an ophthalmologist or optometrist and record of gonioscopy; and (3) no history of intraocular pressure (IOP)-lowering drops, laser peripheral iridotomy (LPI), or intraocular surgery.

METHODS

Cox proportional hazards models were developed to assess factors associated with diagnostic conversion, defined as a change in ICD code from ANA to PACG.

MAIN OUTCOME MEASURES

New diagnosis of PACG within the 6-year study period recorded after an index diagnosis of ANA.

RESULTS

Among 3985 patients meeting inclusion criteria, 459 (11.52%) had detected diagnostic conversion to PACG within the study period. The conversion rate was stable at 3.54% per year after the first 6 months of ANA diagnosis. In the Cox proportional hazards model, age > 70 years and early (within 6 months of ANA diagnosis) need for LPI or IOP-lowering drops were positively associated with diagnostic conversion (hazard ratio [HR] > 1.59; P < 0.02). Cataract surgery at any time and late (after 6 months of ANA diagnosis) need for IOP-lowering drops appeared protective against diagnostic conversion (HR < 0.46; P < 0.004).

CONCLUSIONS

Annual risk of diagnostic conversion from ANA to PACG is relatively low overall; elderly patients are at higher risk whereas patients receiving cataract surgery are at lower risk. The utility of long-term monitoring seems low for most patients with ANA, highlighting the need for improved clinical methods to identify patients at higher risk for PACG.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Increase in anterior chamber angle depth after topical pilocarpine measured by spectral domain optical coherence tomography: A possible additional indicator for laser peripheral iridotomy in primary angle-closure suspects in an opportunistic set-up

Purpose

Indication of laser peripheral iridotomy (LPI) is often conjectural due to dependency on gonioscopy and strict dichotomous classification of occludability. Indentation gonioscopy is the gold standard but is under-utilized for various reasons. The prevalence of primary angle closure disease (PACD) in eastern India is 1.5-1.9%, with a 22% five-year progression rate. Many angle closure patients may go blind without timely diagnosis and iridotomy. General ophthalmologists need alternate, validated methods for diagnoses. Pilocarpine eye drop causes miosis, and flattens the iris, producing angle changes detectable by spectral domain optical coherence tomography (SD-OCT). We hypothesized that the amount of angle change may be a suitable indicator for iridotomy.

Methods

Our prospective cross-sectional single-masked observational study evaluated pilocarpine-induced changes in angle parameters detected by SD-OCT. Out of 372 patients enrolled, 273 patients (539 eyes) remained, with a mean age of 48.6 years (SD = 10.36). All eyes were graded by the Van Herick (VH) method, gonioscopy, and anterior segment (AS) SD-OCT and reassessed after pilocarpine drops.

Results

The sensitivity and specificity of tomography measurements against gonioscopy grades were 61% and 85%, respectively. The receiver operating characteristic (ROC) curve was 0.85. Pilocarpine-induced angle widening was significant in gonioscopically narrower angles. Low Van Herick grades (217 eyes), narrow gonioscopy grades (238 eyes), and a narrow OCT angle value (165 eyes) were candidates for iridotomy.

Conclusion

Our study results showed that pilocarpine-induced angle widening detected by SD-OCT could be a strong objective indicator for LPI.

Racial and Sociodemographic Disparities in the Detection of Narrow Angles before Detection of Primary Angle-Closure Glaucoma in the United States

PURPOSE

To assess the proportion of newly diagnosed cases of primary angle-closure glaucoma (PACG) with and without prior diagnosis of anatomical narrow angle (ANA) and to identify sociodemographic risk factors for late detection (PACG without prior ANA diagnosis).

DESIGN

Retrospective cohort study.

METHODS

One hundred two thousand six hundred seventeen patients with PACG were identified from the Optum Clinformatics Data Mart Database (2007-2019). Patients with newly diagnosed PACG met the following criteria: (1) diagnosis made by an ophthalmologist, (2) disease observable for at least 12 months before diagnosis, and (3) no history of treatment before diagnosis unless preceded by a diagnosis of ANA. Multivariate logistic regression modeling was performed to identify sociodemographic risk factors for late detection.

MAIN OUTCOME MEASURES

Proportion of patients with newly diagnosed PACG without prior ANA diagnosis and sociodemographic factors associated with late detection.

RESULTS

Thirty-one thousand forty-four patients were eligible. More than 70% of PACG cases were detected without prior ANA diagnosis, regardless of patient age, sex, or race. The odds of late detection were significantly higher (P < 0.001) among men (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.25-1.40), Black patients (OR, 1.25; 95% CI, 1.15-1.37), and patients 80 years of age or older (OR, 1.28; 95% CI, 1.11-1.47) or living in Southern (OR, 1.30; 95% CI, 1.22-1.40) or Pacific (OR, 1.27; 95% CI, 1.16-1.36) regions. Findings were similar for patients with PACG with a record of gonioscopy and treatment or with a 24-month lookback period.

CONCLUSIONS

Most patients who receive a new diagnosis of PACG in the United States do not have a prior diagnosis of ANA. The elderly, men, and Black patients are at higher risk of late detection. A need exists for increased disease awareness among providers and more accessible tools to detect patients at risk of developing PACG.

Self-identified Black Race as a Risk Factor for Intraocular Pressure Elevation and Iritis Following Prophylactic Laser Peripheral Iridotomy

PRCIS

In primary angle closure suspects (PACS), self-identified Black race was a risk factor for intraocular pressure (IOP) elevation and iritis following laser peripheral iridotomy (LPI). Laser type was not associated with either immediate post-LPI IOP elevation or iritis in multivariate analysis.

PURPOSE

The aim was to determine the impact of laser type and patient characteristics on the incidence of IOP elevation and iritis after LPI in PACS.

MATERIALS AND METHODS

The electronic medical records of 1485 PACS (2407 eyes) who underwent either neodymium-doped yttrium-aluminum-garnet or sequential argon and neodymium-doped yttrium-aluminum-garnet LPI at the University of Pennsylvania between 2010 and 2018 were retrospectively reviewed. Average IOP within 30 days before LPI (baseline IOP), post-LPI IOP within 1 hour, laser type, laser energy, and the incidence of new iritis within 30 days following the procedure were collected. Multivariate logistic regression accounting for intereye correlation was used to assess factors associated with incidence of post-LPI IOP elevation and iritis, adjusted by age, sex, surgeon, and histories of autoimmune disease, diabetes, and hypertension.

RESULTS

The incidence of post-LPI IOP elevation and iritis were 9.3% (95% confidence interval: 8.1%-10.5%) and 2.6% (95% CI: 1.9%-3.2%), respectively. In multivariate analysis, self-identified Black race was a risk factor for both IOP elevation [odds ratio (OR): 2.08 compared with White; P=0.002] and iritis (OR: 5.07; P<0.001). Higher baseline IOP was associated with increased risk for post-LPI IOP elevation (OR: 1.19; P<0.001). Laser type and energy were not associated with either post-LPI IOP elevation or iritis (P>0.11 for all).

CONCLUSIONS

The incidence of immediate IOP elevation and iritis following prophylactic LPI was higher in Black patients independent of laser type and energy. Heightened vigilance and increased medication management before and after the procedure are suggested to help mitigate these risks.

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.

Factors Associated with Interventions after Laser Peripheral Iridotomy for Primary Angle-Closure Spectrum Diagnoses

PURPOSE

To assess factors associated with receipt of subsequent medical, laser, or surgical interventions after laser peripheral iridotomy (LPI).

DESIGN

Retrospective review.

PARTICIPANTS

A total of 1271 eyes in 692 subjects with narrow angles (NAs) that were treated with LPI.

METHODS

Demographic and clinical factors associated with primary angle-closure (PAC) or PAC glaucoma (PACG) versus PAC suspect (PACS) diagnosis and use of glaucoma medications at the time of LPI, as well as factors predictive of subsequent addition of glaucoma medications, and receipt of selective laser trabeculoplasty (SLT), cataract surgery, and glaucoma surgery were assessed using logistic regression with generalized estimating equations. Kaplan-Meier curves and Cox proportional-hazards regression analysis were used to assess baseline factors affecting the time to SLT, cataract surgery, or glaucoma surgery.

MAIN OUTCOME MEASURES

Diagnosis of PAC/PACG and medical, laser, or surgical interventions after LPI.

RESULTS

African Americans (odds ratio [OR], 2.12; P < 0.001) were significantly more likely than whites to have PAC/PACG than PACS and to already be taking glaucoma medications (OR, 2.25, P < 0.001) at the time of LPI. In multivariable logistic regression analysis, African Americans were significantly more likely to be prescribed additional glaucoma medications after LPI (OR, 1.73; P = 0.025) and receive glaucoma surgery (OR, 2.7; P = 0.007), but were less likely to receive SLT (OR, 0.37; P = 0.009). In multivariate Cox proportional-hazards regression analysis, African Americans had longer time to SLT than whites (hazard ratio [HR], 0.41; P = 0.022), but a shorter time to glaucoma surgery (HR, 2.57; P = 0.004). There was no significant association between race and the likelihood of cataract surgery or time to cataract surgery (P > 0.10).

CONCLUSIONS

African Americans were more likely than whites to carry a diagnosis of PAC or PACG at the time of LPI and were significantly more likely to be prescribed additional glaucoma medications and require glaucoma surgery after LPI. Improved screening methods that target African Americans with NAs are needed so that preventive interventions such as LPI can be performed earlier to decrease the risk of progression.