Incidence of acute angle-closure glaucoma after pharmacologic mydriasis

Incidence of acute angle closure in patients with primary angle closure without prophylactic iridotomy during pharmacological mydriasis for cataract surgery

The objective was to study the incidence of acute primary angle closure (acute PAC) during pharmacologic mydriasis before cataract surgery and changes in anterior chamber angle parameters in patients with primary angle closure diseases (PACD) with and without prophylaxis laser peripheral iridotomy (LPI). This was a prospective, comparative study of cataract patients with PACD with and without prophylaxis LPI presented at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand during June 2022 to December 2023. The incidence of acute PAC during pharmacologic mydriasis prior to cataract surgery was recorded. Changes in anterior chamber depth (ACD) and anterior chamber angle parameters measured with anterior segment optical coherence tomography before and after cataract surgery were compared between groups using Student t test. There were 195 eyes of 116 patients with a mean age of 70 years enrolled in the study. Eighty patients were women and 36 were men. There were 99 eyes without prophylaxis LPI and 96 eyes with LPI. There was significantly more angle-closure glaucoma in the non-LPI group than in the LPI group. Preoperatively, all anterior chamber angle parameters were significantly greater in the LPI group than in the non-LPI group (P < .001 all parameters), except ACD (P = .83) and anterior chamber width (ACW) (P = .30). All participants underwent uneventful cataract surgery. Postoperatively, all parameters of the anterior chamber angle and ACD increased significantly in both groups. When comparing between groups, all postoperative anterior chamber angle parameters were not significantly different between the groups, but ACD was significantly greater (P = .036) and ACW was lower in the LPI group (P = .008). There was no incidence of acute PAC occurring during pharmacological mydriasis before cataract surgery in both groups. There was no incidence of acute PAC in patients with and without prophylaxis LPI during pharmacological mydriasis in the preoperative preparation for cataract surgery. Eyes without LPI showed significantly lower preoperative anterior chamber angle parameters compared to eyes with previous LPI, but not significantly different postoperatively. The benefits of prophylactic LPI for PACD scheduled for cataract surgery must be further investigated.

Association of Contrast Sensitivity With Eye Disease and Vision-Related Quality of Life

PURPOSE

To investigate contrast sensitivity (CS) as a screening tool to detect eye disease and assess its association with both eye disease and vision-related quality of life.

DESIGN

Cross-sectional study.

METHODS

Setting and population: Adults receiving care from a free clinic and a Federally Qualified Health Center in Michigan.

MAIN OUTCOME MEASURES

Screening positive for eye disease and Visual Function Questionnaire (VFQ) score.

OBSERVATION

Participants received a vision exam reviewed via telemedicine for disease, completed a demographic survey, and the 9-item VFQ. The ability of CS to predict eye disease was explored and area under the curve (AUC) is reported. Logistic and linear regression were used to investigate the continuous effect of CS on the probability of screening positive for eye disease and VFQ score, respectively, adjusting for age and visual acuity.

RESULTS

1159 included participants were, on average, 54.9 ± 14.5 years old, 62% identified as female, 34% as White, 54% as Black, 10% as Hispanic/Latino, and reported mean VFQ score of 79.7 ± 15.3. CS ranged from 0.00 to 1.95 log units (mean = 1.54 ± 0.24), 21% of eyes had glaucoma, 19% cataract, 6% DR, and 2% AMD. AUCs were 0.53 to 0.73. A 0.3 log unit decrease in better eye CS was associated with increased odds of glaucoma (odds ratio [OR] = 1.35, confidence interval [CI] = 1.09-1.67), cataract (OR = 1.35, CI = 1.05-1.72), DR (OR = 2.05, CI = 1.51-2.77), and AMD (OR = 2.08, CI = 1.10-3.91). A 0.3 log unit increase in better eye CS was associated with a 5.9 unit increase in VFQ.

CONCLUSION

While CS alone is not sufficient to identify people with eye disease, it is an important measure of visual function that can add value to comprehensive eye screening.

Risk Factors for Nondiagnostic Imaging in a Real-World Deployment of Artificial Intelligence Diabetic Retinal Examinations in an Integrated Healthcare System: Maximizing Workflow Efficiency Through Predictive Dilation

OBJECTIVE

In the pivotal clinical trial that led to Food and Drug Administration De Novo "approval" of the first fully autonomous artificial intelligence (AI) diabetic retinal disease diagnostic system, a reflexive dilation protocol was used. Using real-world deployment data before implementation of reflexive dilation, we identified factors associated with nondiagnostic results. These factors allow a novel predictive dilation workflow, where patients most likely to benefit from pharmacologic dilation are dilated a priori to maximize efficiency and patient satisfaction.

METHODS

Retrospective review of patients who were assessed with autonomous AI at Johns Hopkins Medicine (8/2020 to 5/2021). We constructed a multivariable logistic regression model for nondiagnostic results to compare characteristics of patients with and without diagnostic results, using adjusted odds ratio (aOR). P < .05 was considered statistically significant.

RESULTS

Of 241 patients (59% female; median age = 59), 123 (51%) had nondiagnostic results. In multivariable analysis, type 1 diabetes (T1D, aOR = 5.82, 95% confidence interval [CI]: 1.45-23.40, P = .01), smoking (aOR = 2.86, 95% CI: 1.36-5.99, P = .005), and age (every 10-year increase, aOR = 2.12, 95% CI: 1.62-2.77, P < .001) were associated with nondiagnostic results. Following feature elimination, a predictive model was created using T1D, smoking, age, race, sex, and hypertension as inputs. The model showed an area under the receiver-operator characteristics curve of 0.76 in five-fold cross-validation.

CONCLUSIONS

We used factors associated with nondiagnostic results to design a novel, predictive dilation workflow, where patients most likely to benefit from pharmacologic dilation are dilated a priori. This new workflow has the potential to be more efficient than reflexive dilation, thus maximizing the number of at-risk patients receiving their diabetic retinal examinations.

Michigan Screening and Intervention for Glaucoma and Eye Health Through Telemedicine Program: First-Year Outcomes and Implementation Costs

PURPOSE

The Michigan Screening and Intervention for Glaucoma and Eye Health Through Telemedicine (MI-SIGHT) program aims to engage people who are at high risk of glaucoma; we assess first-year outcomes and costs.

DESIGN

Clinical cohort study.

METHODS

Participants ≥18 years of age were recruited from a free clinic and a federally qualified health center in Michigan. Ophthalmic technicians in the clinics collected demographic information, visual function, ocular health history, measured visual acuity, refraction, intraocular pressure, pachymetry, pupils, and took mydriatic fundus photographs and retinal nerve fiber layer optical coherence tomography. Data were interpreted by remote ophthalmologists. During a follow-up visit, technicians shared ophthalmologist recommendations, dispensed low-cost glasses, and collected participant satisfaction. The primary outcome measures were prevalence of eye disease, visual function, program satisfaction, and costs. Observed prevalence was compared with national disease prevalence rates using z tests of proportions.

RESULTS

Among 1171 participants, the average age was 55 years (SD 14.5 years), 38% were male, 54% identified as Black, 34% as White, 10% as Hispanic, 33% had less than or equal to a high school education, and 70% had an annual income <$30,000. The prevalence of visual impairment was 10.3% (national average 2.2%), glaucoma and suspected glaucoma 24% (national average 9%), macular degeneration 2.0% (national average 1.5%), and diabetic retinopathy 7.3% (national average 3.4%) (P < .0001). Seventy-one percent of participants received low-cost glasses, 41% were referred for ophthalmology follow-up, and 99% were satisfied or very satisfied with the program. Startup costs were $103,185; recurrent costs were $248,103 per clinic.

CONCLUSIONS

Telemedicine eye disease detection programs in low-income community clinics effectively identify high rates of pathology.

Risk of acute angle-closure and changes in intraocular pressure after pupillary dilation in patients with diabetes

BACKGROUND

To evaluate the risk of AAC and intraocular pressure (IOP) changes in diabetic patients after pupil dilation.

METHODS

This cross-sectional study enrolled 2,287 diabetic patients among community residents in Guangzhou, China. All participants underwent routine pupil dilation unless they had a history of glaucoma. IOP was measured using a non-contact tonometer before and one hour after pupil dilation with tropicamide 0.5% and phenylephrine 0.5% eye drop. The proportion of AAC and changes in IOP after pupil dilation were evaluated.

RESULTS

Only one of the 2,287 participants (0.04%) with diabetes developed post-dilation AAC. The mean pre and post-dilation IOP in the right was 16.1 ± 2.7 and 16.5 ± 2.8 mmHg (P < 0.001); mean pre and post-dilation IOP in the left was 16.5 ± 2.7 and 16.8 ± 2.8 mmHg (P < 0.001). Sixty-one participants (2.7%) showed an increase in IOP ≥ 5 mmHg and 25 participants (1.1%) showed a post-dilation IOP > 25 mmHg, including 11 participants (0.5%) who had both an increase in IOP ≥ 5 mmHg and post-dilation IOP > 25 mmHg. Lower pre-dilation IOP (OR = 0.827; 95% CI, 0.742-0.922; P = 0.001) and shallower anterior chamber depth (ACD) (OR = 0.226; 95% CI, 0.088-0.585; P = 0.002) were significant risk factors for an increase in IOP ≥ 5 mmHg in multivariate logistic regression analysis.

CONCLUSIONS

The risk of developing AAC after pupil dilation in diabetic patients was very low. Lower pre-dilation IOP and shallower ACD are risk factors for increased post-dilation IOP.

Artificial Intelligence for Diabetic Retinopathy Screening Using Color Retinal Photographs: From Development to Deployment

Diabetic retinopathy (DR), a leading cause of preventable blindness, is expected to remain a growing health burden worldwide. Screening to detect early sight-threatening lesions of DR can reduce the burden of vision loss; nevertheless, the process requires intensive manual labor and extensive resources to accommodate the increasing number of patients with diabetes. Artificial intelligence (AI) has been shown to be an effective tool which can potentially lower the burden of screening DR and vision loss. In this article, we review the use of AI for DR screening on color retinal photographs in different phases of application, ranging from development to deployment. Early studies of machine learning (ML)-based algorithms using feature extraction to detect DR achieved a high sensitivity but relatively lower specificity. Robust sensitivity and specificity were achieved with the application of deep learning (DL), although ML is still used in some tasks. Public datasets were utilized in retrospective validations of the developmental phases in most algorithms, which require a large number of photographs. Large prospective clinical validation studies led to the approval of DL for autonomous screening of DR although the semi-autonomous approach may be preferable in some real-world settings. There have been few reports on real-world implementations of DL for DR screening. It is possible that AI may improve some real-world indicators for eye care in DR, such as increased screening uptake and referral adherence, but this has not been proven. The challenges in deployment may include workflow issues, such as mydriasis to lower ungradable cases; technical issues, such as integration into electronic health record systems and integration into existing camera systems; ethical issues, such as data privacy and security; acceptance of personnel and patients; and health-economic issues, such as the need to conduct health economic evaluations of using AI in the context of the country. The deployment of AI for DR screening should follow the governance model for AI in healthcare which outlines four main components: fairness, transparency, trustworthiness, and accountability.

Acute Angle-Closure Attacks Are Uncommon in Primary Angle-Closure Suspects after Pharmacologic Mydriasis: The Zhongshan Angle-Closure Prevention Trial

PURPOSE

Angle-closure glaucoma is a major cause of blindness worldwide that carries an excessive risk of severe, bilateral visual impairment. A common concern among clinicians is the precipitation of acute angle-closure (AAC) attacks because of mydriasis. We evaluated the risk of AAC after pharmacologic dilation in Chinese individuals classified as having bilateral primary angle-closure suspects (PACSs).

DESIGN

Randomized, interventional, controlled trial.

PARTICIPANTS

A total of 889 patients with bilateral PACSs, aged between 50 and 70 years, were identified through community screening in Guangzhou, China, and enrolled in the study.

METHODS

In the Zhongshan Angle-Closure Prevention Trial, bilateral PACSs were treated with laser peripheral iridotomy (LPI) in 1 randomly selected eye, with the fellow eye serving as an untreated control. Over 72 months of follow-up, the participants had their pupils pharmacologically dilated 6 times with 5% phenylephrine and 0.5% tropicamide.

MAIN OUTCOME MEASURES

Incidence and risk of post-mydriasis AAC in LPI-treated and untreated, control eyes classified as PACSs.

RESULTS

One bilateral AAC attack occurred after mydriasis at the 2-week post-LPI visit. No other AAC events occurred in the LPI-treated eyes. In the untreated eyes, 4 additional attacks occurred: 2 occurred after dilation (1 at 54 months and 1 at 72 months of follow-up) and 2 occurred spontaneously. The risk of post-mydriasis AAC in the untreated eyes was 1 attack in 1587 dilations. The risk of spontaneous AAC in the untreated eyes was 0.44 per 1000 eye-years (95% confidence interval, 0.11-1.77 per 1000 eye-years).

CONCLUSIONS

The risk of incident AAC attacks in PACSs was extremely low, even in a higher-risk group that underwent repeated pharmacologic pupillary dilation over 6 years of follow-up. Prophylactic LPI reduced this small but real risk. This trial was registered at ISRCTN.com as ISRCTN45213099.

Pupillary Dilation in Research: More than Meets the Eye

Purpose: Pupil dilation is a commonly used procedure in vision research. While often considered a minimal risk procedure, there is the potential for significant adverse effects. Methods: Currently, there is variance in practices and protocols among researchers and institutions, perhaps due to a lack of guidelines for safe pupil dilation practices in research settings. In this perspective, we explore variables that can increase the potential for adverse effects and provide suggestions to limit their impact. Prior to dilation, an investigator can assess an individual's medical status and drug regimen when deciding upon a mydriatic agent to be used. Results: Assessing the angle through a variety of methods (i.e. penlight test, van Herick slit lamp, optical coherence tomography, gonioscopy) can also prevent inappropriate dilation of pupils with concerning anatomical features. During dilation, an investigator should look to limit the potential of infection and use caution in repeat dosing of dilation-resistant pupils. Conclusions: Post-dilation, an investigator should closely monitor eyes with elevated risk factors and improve an individual's health literacy on angle closure complications. When combined with proper informed consent processes regarding adverse effects, the aforementioned can allow for risk mitigation in studies using pupil dilation.

The Impact of Pharmacological Dilation on Intraocular Pressure in Primary Angle Closure Suspects

PURPOSE

To assess changes in intraocular pressure (IOP) 1 hour after pharmacological dilation in eyes treated with laser peripheral iridotomy (LPI) and untreated fellow eyes of primary angle closure suspects (PACS).

DESIGN

A prospective randomized, fellow-eye controlled trial.

METHODS

A total of 889 participants with PACS aged 50 to 70 years with LPI in 1 randomly selected eye and a fellow untreated eye were included. All participants underwent comprehensive examinations before and at 2 weeks, 6 months, 18 months, 36 months, 54 months, and 72 months after LPI. The IOP was measured using Goldmann applanation tonometry before and 1 hour after pharmacological dilation.

RESULTS

The mean predilation IOP in the untreated eyes was 14.8 ± 2.7 mm Hg, which increased to 16.4 ± 2.7 mm Hg after pharmacological dilation (P < .001). The treated and untreated eyes had similar predilation and postdilation IOP (all P > 0.05). The average postdilation IOP elevation was 1.5 mm Hg in the treated eyes and 1.6 mm Hg in the untreated eye, without significant differences (P = .802). Lower predilation IOP (P < .001), smaller AOD500 (P = 0.001), smaller ARA500 (P = .030), smaller TISA500 (P = .043), and larger Iarea (P < 0.001) were associated with postdilation IOP elevation of 5 mm Hg and greater. Three untreated eyes (1.04 per 1000 pupil dilation) and 1 treated eye (0.34 per 1000 pupil dilation) developed acute angle closure (AAC) after dilation during the 72-month follow-up.

CONCLUSIONS

Postdilation IOP elevation was similar among treated and untreated eyes, and the risk of developing AAC was very low, even among patients with PACS. Routine LPI before pupil dilation for people with PACS is not recommended.

Bilateral Acute Angle-Closure Glaucoma: A Case Report of an Unusual Cause of Acute Headache in a Child

Introduction

Acute angle-closure glaucoma (AACG) is typically considered a disease of adulthood. However, AACG may occasionally be seen in children. The clinical presentation is similar to adults, including headache, vomiting, and eye pain. However, the etiology of angle closure in children is different and most often associated with congenital anterior segment abnormalities. A precipitating factor of AACG in children with previous established, anterior segment abnormalities is eye dilation, which may occur during routine ophthalmological examination with topical mydriasis, or physiologic mydriasis upon entering a dark room.

Case Report

We describe a 5-year-old child with a history of severe prematurity and retinopathy of prematurity (ROP) presenting with bilateral AACG following a routine outpatient, dilated ophthalmological examination. While angle-closure glaucoma has previously been reported in cases of ROP, a bilateral acute attack of AACG following pupil dilation in regressed ROP has hitherto been unreported.

Conclusion

Given the association of ROP and AACG, it can be expected that as the survival rate of premature infants improves, the incidence of ROP and AACG may also increase. It is therefore prudent for the emergency physician to have AACG on the differential for pediatric patients with headache and eye pain.

Michigan Screening and Intervention for Glaucoma and Eye Health Through Telemedicine (MI-SIGHT): Baseline Methodology for Implementing and Assessing a Community-based Program

PRECIS

The Michigan Screening and Intervention for Glaucoma and eye Health through Telemedicine (MI-SIGHT) program leverages community-engaged research, telemedicine, and health coaching to overcome key logistical and psychosocial barriers to improve glaucoma screening in underserved communities.

PURPOSE

To describe the methodology of the implementation and evaluation of the MI-SIGHT Program.

METHODS

The MI-SIGHT Program uses community engagement, telemedicine, and health coaching to overcome key logistical and psychosocial barriers to glaucoma identification and care among underserved populations. The MI-SIGHT Program will be evaluated in 2 community clinics: Hamilton Community Health Network, a federally qualified health center in Flint, Michigan, and the Hope Clinic, a free clinic in Ypsilanti, Michigan. A Community Advisory Board including the research team and health care providers, administrators, and patients from both clinics will guide program implementation. An ophthalmic technician at the community clinics will conduct screening tests for glaucoma and eye disease. The data will be transmitted through electronic health record to be reviewed by an ophthalmologist who will make recommendations for follow-up care. The ophthalmic technician will conduct a return visit to fit low-or no-cost glasses, help arrange follow-up with an ophthalmologist, and provide education. Those diagnosed with glaucoma or suspected glaucoma will be randomized to standard education or personalized glaucoma education and coaching. Costs will be assessed.

RESULTS

The authors hypothesize that the MI-SIGHT Program will detect a higher prevalence rate of glaucoma than that found in the general population, improve upon presenting visual acuity, enhance vision-related quality of life, and demonstrate that personalized glaucoma education and coaching improve adherence to follow-up care.

CONCLUSION

The MI-SIGHT Program may serve as a model for glaucoma screening and care in high-risk communities.

Effectiveness of topical cycloplegics as anterior segment analgesics: systematic review and meta-analysis

OBJECTIVE

Topical cycloplegic agents often are used in ophthalmology in the context of management of ocular inflammation. Preliminary searches of the literature provided little evidence to support their use in relieving pain or reducing inflammation. The goal of this study was to evaluate the current literature for any evidence regarding the effectiveness of cycloplegics for treatment of pain or inflammation in patients with anterior segment injury or inflammation through a systematic review and meta-analysis.

METHODS

Using multiple keywords relating to cycloplegics and inflammatory and infectious eye conditions, a search was conducted on multiple scientific databases for relevant articles. A 2-level screening approach was used and articles that were relevant to the topic were included in the systematic review. Data from these articles, if applicable, were extracted for meta-analyses. Statistical assessments involved computation of I²statistics, Z-value, and χ² statistics.

RESULTS

We screened 5753 articles for relevance. Seven were included in the systematic review and 5 were included in the meta-analysis. There was considerable heterogeneity between the included studies. Statistical analysis revealed significant reductions in pain using homatropine and cyclopentolate after 2 days. Nonsignificant changes in the anterior chamber cells and flare were seen using cyclopentolate and atropine at different follow-up times.

CONCLUSIONS

Little published evidence exists in the literature to guide the use of cycloplegics on relieving pain and treating inflammation. Therefore, higher-quality randomized controlled trials with longer follow-up times are needed to fully understand the role that cycloplegics play in reducing pain in inflammatory conditions.

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.

Determinants of post-mydriatic intraocular pressure in phakic eyes with prevalent angle closure diseases

PURPOSE

This study aimed to identify acute angle closure (AAC) risk following pharmacologic mydriasis and the factors affecting post-mydriatic intraocular pressure (IOP) in a population with a high prevalence of angle closure disease.

METHODS

In total, 460 individuals aged ≥ 72 years were enrolled in this cross-sectional community-based screening program. IOP was measured at baseline and 1 hour after mydriasis. Individuals with post-mydriatic IOP spike > 6 mmHg received indentation gonioscopy and IOP-lowering medication. Linear regression analysis was used to identify ocular parameters associated with post-mydriatic IOP elevation.

RESULTS

The mean age of participants was 77.8 ± 4.1 years, and 65.4% of them were men. In total, 21 eyes of 16 participants (3.48%) had post-mydriatic IOP spikes (range: 6-13.7 mmHg); among them, 15 eyes had an IOP of > 21 mmHg. None of the participants developed AAC. All eyes with IOP spikes were phakic, except for one with pseudophakic angle closure. Analysis of 381 participants with at least one phakic eye revealed that higher post-mydriatic IOP and IOP changes were associated with narrower angle grading, more extensive peripheral anterior synechiae, shallower central anterior chamber, and thicker lens. According to multiple linear regression analysis, post-mydriatic IOP was independently associated with baseline IOP and factors suggestive of crowded anterior chamber based on gonioscopic findings and central or peripheral anterior chamber depth evaluation in conjunction with lens thickness.

CONCLUSION

Post-mydriatic IOP should be measured in phakic eyes with a crowded anterior chamber. Post-mydriatic IOP spikes can be effectively blunted with intervention to prevent AAC.

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.

[Drug-induced glaucoma]

Glaucoma is seen as a heterogeneous group of diseases characterized by optical neuropathy with associated visual field loss; one of the main risk factors for its development is increased intraocular pressure (IOP). In the case of drug-induced glaucoma (DIG), patients develop elevated IOP, optic neuropathy and visual field defects associated with the use of certain drugs. Corticosteroids are one of the most well-known classes of drugs that can cause an increase in IOP through the open-angle mechanism. Drug-induced glaucoma, which develops similarly to open-angle glaucoma, can also be caused by some non-steroidal anti-inflammatory agents, antibodies to the endothelial growth factor, etc. Classes of drugs that can cause angle-closure glaucoma include topical anticholinergic or sympathomimetic drops, tricyclic antidepressants, monoamine oxidase inhibitors, antihistamines, antiparkinsonian drugs, antipsychotic drugs, antispasmodics. Products containing sulfa group drugs can cause DIG due to a different closing angle mechanism involving a forward rotation of the ciliary body. It is important for medical practitioners to be aware of this unwanted drug reaction in order to prevent, detect and treat DIG. In the case of drug-induced increase in IOP, if the underlying disease allows discontinuation of drugs, this measure usually leads to normalization of IOP. In cases when the patient's IOP does not normalize after discontinuation of steroids or when they must continue to take corticosteroids, the administration of topical drugs for the treatment of glaucoma should be considered.

A review of systemic medications that may modulate the risk of glaucoma

With increasing longevity, patients are developing more and more chronic diseases that require treatment with medications. Yet, it is not fully understood the extent by which these systemic medications affect ocular structures and whether they may increase or decrease the risk of sight-threatening ocular diseases. This review provides a summary of reported associations between different systemic medications and the risk of developing glaucoma or experiencing disease progression. Medication classes covered in this review that are known to or may modulate the risk of open-angle glaucoma include corticosteroids, beta blockers, calcium channel blockers, metformin, statins, selective serotonin reuptake inhibitors, bupropion, postmenopausal hormones, and cannabinoids. Medication classes addressed in this review that may increase the risk of angle closure glaucoma include anticholinergics, adrenergic agonists, certain classes of antidepressants, sulfonamides, and topiramate.

Water-drinking Test and Pharmacologic Mydriasis as Provocative Tests in Primary Angle Closure Suspects

Purpose

To compare the water-drinking test (WDT) and pharmacologic mydriasis as provocative tests in patients with primary angle closure suspect (PACS).

Methods

This observational non-randomized comparative study evaluated changes in intraocular pressure (IOP) in 21 patients with PACS who underwent pharmacologic mydriasis and compared it with IOP changes in 26 patients given the WDT. Ocular biometric and anterior chamber parameters were also assessed. Tests were repeated on the same patient two weeks after performing laser peripheral iridotomy (LPI).

Results

The mean age ± standard deviation was 60 ± 7 and 57 ± 9 years in the mydriasis and WDT groups, respectively (P = 0.201). Before LPI, both provocative tests were associated with a significant increase in IOP (mydriasis: 15.1 ± 3.1 to 16.6 ± 3.5 mmHg, P = 0.025; WDT: 16.2 ± 2.8 to 18.5 ± 3.3 mmHg, P < 0.001). However, the IOP changes were not statistically different between groups (P = 0.102). After LPI, only the WDT group showed a continued significant IOP elevation after the test (mydriasis: 16.4 ± 3.3 to 16.7 ± 3.5 mmHg, P = 0.569; WDT: 14.9 ± 3.0 to 17.8 ± 4.1 mmHg, P < 0.001). The post-test IOP change was significantly greater in the WDT than in the mydriasis group (3.0 versus 0.3 mmHg, respectively; P = 0.002). Step-wise multiple regression analysis verified the type of provocative test as the only independent factor affecting the post-test IOP change after LPI (regression coefficient: 2.664; P = 0.002).

Conclusion

Pharmacologic mydriasis and the WDT had similar IOP elevation before LPI, but after LPI, IOP elevation was much greater in the WDT group.

Factors Associated With Zonular Instability During Cataract Surgery in Eyes With Acute Angle Closure Attack

PURPOSE

To compare the demographics and ocular characteristics, including anterior segment optical coherence tomography images and zonular instability, in eyes with a history of acute angle closure (AAC) attack and subsequent cataract surgery.

DESIGN

Retrospective case-control study.

METHODS

A total of 68 eyes of 56 patients with a history of AAC attack who underwent cataract surgery were enrolled. Fourteen eyes were assigned to the zonular instability (+) group and 54 were assigned to the zonular instability (-) group based on the presence of zonular instability during cataract surgery. The peak intraocular pressure, preoperative spherical equivalent (SE), axial length (AL), anterior chamber depth (ACD), and lens vault (LV) were measured and compared between 2 groups. Intereye (intraindividual) comparison was also performed. Factors associated with zonular instability were assessed.

RESULTS

In the zonular instability (+) group, 9 eyes were from male and 5 from female participants. Eyes in the zonular instability (+) group showed less hyperopic SE values, longer AL, shallower ACD, and higher LV, as compared with those in the zonular instability (-) group (all P ≤ .001). Moreover, eyes in the zonular instability (+) group had less hyperopic SE, shallower ACD, and higher LV than their fellow eyes. Less hyperopic SE, longer AL, and higher LV were significantly associated with zonular instability on multivariate logistic regression analysis.

CONCLUSIONS

Clinicians should consider the possibility of zonular instability during cataract surgery for eyes with less hyperopic SE, longer AL, and higher LV among those with a history of AAC attack.

The incidence of acute angle closure in Scotland: a prospective surveillance study

PURPOSE

To estimate the incidence, and describe the clinical features and short-term clinical outcomes of acute angle closure (AAC).

METHODS

Patients with newly diagnosed AAC were identified prospectively over a 12-month period (November 2011 to October 2012) by active surveillance through the Scottish Ophthalmic Surveillance Unit reporting system. Data were collected at case identification and at 6 months follow-up.

RESULTS

There were 114 cases (108 patients) reported, giving an annual incidence of 2.2 cases (95% CI 1.8 to 2.6) or 2 patients (95% CI 1.7 to 2.4) per 1 00 000 in the whole population in Scotland. Precipitating factors were identified in 40% of cases. Almost one in five cases was associated with topical dilating drops. Best-corrected visual acuity (BCVA) at presentation ranged from 6/6 to perception of light. The mean presenting intraocular pressure (IOP) was 52 mm Hg (SD 11). Almost 30% cases had a delayed presentation of 3 or more days. At 6 months follow-up, 75% had BCVA of 6/12 or better and 30% were found to have glaucoma at follow-up. Delayed presentation (≥3 days) was associated with higher rate of glaucoma at follow-up (22.6% vs 60.8%, p<0.001), worse VA (0.34 vs 0.74 LogMAR, p<0.0001) and need for more topical medication (0.52 vs 1.2, p=0.003) to control IOP.

CONCLUSION

The incidence of AAC in Scotland is relatively low compared with the Far East countries, but in line with previous European data. Almost one in five cases were associated with pupil dilation for retinal examination.

An uncommon case of intermittent Pourfour du Petit Syndrome associated with acute angle-closure glaucoma successfully treated by laser iridotomy

PURPOSE

To describe a case of acute angle-closure glaucoma secondary to intermittent mydriasis related to Pourfour du Petit Syndrome caused by tracheal deviation.

MATERIALS AND METHODS

A 70-year-old Caucasian woman visited the Emergency Room of the University Eye Clinic complaining of blurring of vision and difficulty to move superior eyelid in her right eye. Examination revealed reactive mydriasis, and upper lid retraction on the right side. The rest of the ophthalmological examination was normal, and a cranial computed tomography (CT) did not identify any abnormalities. A cervical CT showed the presence of an accentuated lateral right convex deviation of the trachea, attributable to a fibrothorax. A right Pourfour du Petit syndrome was suspected. Although the mydriasis had in the meantime vanished, the patient was admitted to the Neurological Clinic.

RESULTS

Five days later she suffered acute pain in her right eye. Ophthalmological examination of the right eye revealed conjunctival hyperemia, marked corneal edema, reduced depth of anterior chamber, permanent mydriasis. As assessed by Goldmann applanation tonometry, intraocular pressure (IOP) was 48 mm Hg. Fundus examination was normal in both eyes. Gonioscopy revealed angle closure in all quadrants. Slit lamp examination of the contralateral eye was normal; IOP was 10 mm Hg. After hypotensive medical therapy, iridotomy with YAG laser was performed. Thereafter, IOP stabilized at 12 mm Hg.

CONCLUSIONS

This is the first report in the literature of a case of acute angle-closure glaucoma secondary to mydriasis related to Pourfour du Petit Syndrome caused by tracheal deviation.

Utility of 1% Tropicamide in Improving the Quality of Images for Tele-Screening of Diabetic Retinopathy in Patients with Dark Irides

PURPOSE

To compare the quality of fundus photographs taken before and after instillation of one drop of tropicamide.

METHODS

The 45º fundus photographs were taken with a non-mydriatic fundus camera in three conditions of the pupil; pre-mydriatic, 10 minutes after one drop of tropicamide, and fully dilated. Two photographs were taken in each condition; one centered on the macula and the other on the optic disc. Two vitreoretinal specialists graded the images.

RESULTS

A total of 1768 fundus photographs of 149 diabetic patients with dark irides were included. There were more ungradable images (38.1% and 50.3%, graders 1 and 2, respectively) in the non-mydriatic state than partially- (4.6% and 11.5%) or fully-dilated (15.4% and 10.0%) conditions (p < 0.001, both graders). Partially and fully dilated states had similar rates of ungradable images (p = 0.56 and p = 0.54, graders 1 and 2, respectively). Test-retest reliability (repeatability) was 92.5% and 74.3% for the two graders, respectively. Inter-grader agreement was moderate (Kappa = 0.50).

CONCLUSION

Non-mydriatic fundus photographs have a high rate of ungradable images in patients with dark irides. Instillation of only one drop of tropicamide improves the quality of fundus photographs, which is not furthered by adding more drops. This strategy can be used in tele-ophthalmology programs.

Angle closure glaucoma in the Northern Ireland Diabetic Retinopathy Screening Programme

PurposeTo ascertain the risk of angle closure glaucoma associated with mydriasis in the Northern Ireland Diabetic Retinopathy Screening Programme.MethodsA retrospective case note review was carried out, cross referencing hospital records with those of the screening programme, to identify episodes of angle closure glaucoma, which occurred within 14 days of a retinopathy screening episode involving pharmacological mydriasis.ResultsThree cases of angle closure following mydriasis for screening were identified. The incidence of angle closure within the screening programme was calculated to be 1 in 31 755 patients dilated or 0.75 patients per year.ConclusionAngle closure is a rare complication of mydriasis used in photographic screening for diabetic retinopathy. We advocate the provision of clear instructions to patients in screening programmes on when and how to access emergency ophthalmic care following dilation to prevent loss of vision in this rare event.

Eye drop neurology

Eye drops can help to diagnose and prevent complications of neurological disorders. Guttae ophthalmicae (eye drops) are generally safe because the drugs rarely achieve significant systemic concentrations, although there are rare exceptions. This article covers contemporary pharmacological pupil testing; how to dilate a pupil safely; common reasons why pupils do not respond to drops; and corneal lubrication to prevent complications of weak eye closure.

Prevalence of glaucoma in an urban West African population: the Tema Eye Survey

IMPORTANCE

Multiple studies have found an increased prevalence, younger age at onset, and more severe course of glaucoma in people of African descent, but these findings are based on studies conducted outside Africa.

OBJECTIVE

To determine the prevalence of glaucoma in an urban West African population of adults.

DESIGN AND SETTING

A population-based, cross-sectional study of adults 40 years and older conducted from September 1, 2006, through December 31, 2008, from 5 communities in Tema, Ghana.

PARTICIPANTS

Participants from randomly selected clusters underwent a screening examination that consisted of visual acuity, frequency doubling perimetry, applanation tonometry, and optic disc photography. Participants who failed any of these tests were referred for complete examination, including gonioscopy, standard automated perimetry, and stereoscopic optic disc photography.

RESULTS

A total of 6806 eligible participants were identified, and 5603 (82.3%) were enrolled in the study. The field examination referred 1869 participants (33.3%) to the clinic examination, and 1538 (82.2%) came for complete examination. A total of 362 participants were identified as having glaucoma of any type and category. Primary open-angle glaucoma was the underlying diagnosis in 342 participants (94.5%). The prevalence of primary open-angle glaucoma was 6.8% overall, increasing from 3.7% among those 40 to 49 years old to 14.6% among those 80 years and older, and was higher in men than in women in all age groups, with an overall male-female prevalence ratio of 1.5. Of the participants with glaucoma, 9 (2.5%) were blind using World Health Organization criteria, and only 12 (3.3%) were aware that they had glaucoma.

CONCLUSIONS AND RELEVANCE

The prevalence of glaucoma is higher in this urban West African population than in previous studies of people of East or South African and of non-African descent. Strategies to identify affected persons and effectively manage the burden of glaucoma are needed in West Africa.

Blindness and visual impairment in an urban West African population: the Tema Eye Survey

OBJECTIVE

To determine the prevalence, causes, and risk factors of blindness and visual impairment among persons aged 40 years or older residing in an urban West African location.

DESIGN

Population-based, cross-sectional study.

PARTICIPANTS

A total of 5603 participants residing in Tema, Ghana.

METHODS

Proportionate random cluster sampling was used to select participants aged 40 years or older living in the city of Tema. Presenting distance visual acuity (VA) was measured at 4 and 1 m using a reduced logarithm of the minimum angle of resolution tumbling E chart and then with trial frame based on autorefraction. A screening examination was performed in the field on all participants. Complete clinical examination by an ophthalmologist was performed on participants with best-corrected visual acuity (BCVA) <20/40 or failure of any screening test.

MAIN OUTCOME MEASURES

Age- and gender-specific prevalence, causes, and risk factors for blindness (VA of <20/400 in the better eye, World Health Organization definition) and visual impairment (VA of <20/40 in the better eye).

RESULTS

A total of 6806 eligible participants were identified, of whom 5603 (82.3%) participated in the study. The mean age (± standard deviation) of participants was 52.7 ± 1 0.9 years. The prevalence of visual impairment and blindness was 17.1% and 1.2%, respectively. After refraction and spectacle correction, the prevalence of visual impairment and blindness decreased to 6.7% and 0.75%, respectively, suggesting that refractive error is the major correctable cause of visual impairment and blindness in this population. Of 65 subjects with a VA <20/400, 22 (34%) were correctable with refraction, 21 to the level of visual impairment and 1 to normal. The remaining 43 patients (66%) had underlying pathology (cataract in 19, glaucoma in 9, nonglaucomatous optic neuropathy in 3, corneal opacities in 3, retinal disease in 3, and undetermined in 5) that prevented refractive correction. Increased age was a significant risk factor for blindness and visual impairment.

CONCLUSIONS

There is a high prevalence of blindness and visual impairment among those aged ≥ 40 years in Tema, Ghana, West Africa. Refractive error is a major cause of blindness and visual impairment in this population, followed by cataract, glaucoma, and corneal disease.

Non-steroidal drug-induced glaucoma

Numerous systemically used drugs are involved in drug-induced glaucoma. Most reported cases of non-steroidal drug-induced glaucoma are closed-angle glaucoma (CAG). Indeed, many routinely used drugs that have sympathomimetic or parasympatholytic properties can cause pupillary block CAG in individuals with narrow iridocorneal angle. The resulting acute glaucoma occurs much more commonly unilaterally and only rarely bilaterally. CAG secondary to sulfa drugs is a bilateral non-pupillary block type and is due to forward movement of iris-lens diaphragm, which occurs in individuals with narrow or open iridocorneal angle. A few agents, including antineoplastics, may induce open-angle glaucoma. In conclusion, the majority of cases with glaucoma secondary to non-steroidal medications are of the pupillary block closed-angle type and preventable if the at-risk patients are recognized and treated prophylactically.

[Is the flashlight test of any use in primary care for detecting eyes with shallow anterior chamber?]

OBJECTIVE

To validate and analyse the usefulness of the flashlight test (FT) in detecting eyes with a shallow anterior chamber in diabetic patients in primary care.

DESIGN

Cross-sectional descriptive study.

SETTING

Urban health centre and a reference ophthalmology department, Logroño, Spain.

PARTICIPANTS

A total of 74 patients with diabetes type 2, selected by consecutive sampling from those seen for an annual check-up. Those patients with movement difficulties, diseases and lesions of the eye, which would hamper the examination, were excluded. A total of 145 eyes were analysed.

INTERVENTION

A family doctor and the resident performed the FT. The ophthalmologist carried out the Van Herick test without knowing the results of the FT.

PRIMARY OUTCOMES

Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were calculated. The reproducibility was calculated using weighted kappa index.

RESULTS

The kappa index was 75%. The specificity was 88.9% and the sensitivity was 98.9% (95% confidence interval (95% CI) 96.1-100.0%). The likelihood that a patient had a negative result could have an angle with a risk of developing glaucoma was 1.1%. The negative likelihood ratio (NLR) was 0.67%. One patient was incorrectly labelled as not having a narrow angle.

CONCLUSIONS

The FT is valid and useful for ruling out shallow anterior chamber in type 2 diabetics. It is a simple and innocuous test that can help the family doctor make a decision on pharmacological mydriasis to observe the back of the eye.

Intraoperative dilated pupil during nasal polypectomy

In endoscopic sinus surgery, it is often desirable to prepare the nasal mucosa with a nasal decongestant to minimise blood loss and enhance the operative field during surgery. A widely used commercially available preparation for such a purpose is a solution containing 5% Lidocaine Hydrochloride and 0.5% Phenylepherine Hydrochloride. We report a case of a unilateral dilated pupil occurring during nasal polypectomy. A dilated pupil during sinus surgery is associated with an intraorbital injury but many commonly used nasal decongestive agents can also cause mydriasis and this knowledge may prevent some anxiety for the unwary ENT surgeon undertaking sinonasal surgery.

Acute angle closure glaucoma after oculoplastic surgery

PURPOSE

To describe two patients with acute angle closure glaucoma after oculoplastic surgery.

DESIGN

Interventional case reports.

METHODS

Review of clinical findings and treatment.

RESULTS

A 61-year-old female developed a painful eye with decreased visual acuity a few days after bilateral blepharoplasty. A 69-year-old male developed a painful red eye with decreased visual acuity a few days after ptosis correction. In both cases the intraocular pressure increased to more than 50 mmHg. Both patients were diagnosed with acute angle closure glaucoma and treated appropriately.

CONCLUSIONS

Acute angle closure glaucoma is a possible complication of oculoplastic surgery.

Screening for glaucoma in Canada: a systematic review of the literature

BACKGROUND

To provide a recommendation on screening for glaucoma in Canada based on a review of recent evidence available in the literature.

METHODS

A systematic literature review was performed to identify publications from MEDLINE, EMBASE, HealthSTAR, and Cochrane databases from 1990 to 2005. Relevant articles were categorized as economic studies, epidemiologic and intervention studies, or policy papers. Web sites and publications from provincial, state, national, and international health authorities were reviewed for policy recommendations and guidelines.

RESULTS

We identified 39 articles (34 epidemiology and intervention, and 5 economic studies) for the review. From the economic studies, 2 were simple cost analyses and 3 were full economic evaluations (cost-effectiveness). Gaps were observed from these economic studies, where incremental cost-effectiveness analyses of modelled screening programmes were not observed. A large number of alternatives (i.e., screening techniques) and diverse outcome measures were found in the 34 epidemiology and intervention studies. This shows that evidence on the effectiveness of glaucoma screening programmes is available to be used in future modelled analyses. Neutral recommendation made by the Canadian Task Force on Periodic Health Examination regarding glaucoma screening in Canada could be related to the lack of reliable data and models used in past cost-effectiveness analyses.

INTERPRETATION

A need exists to reevaluate the cost-effectiveness of a screening programme for glaucoma in Canada with updated efficacy and cost data. Health and monetary benefits could be improved compared with current practice and decision-makers would have the best available data when reevaluating the policy on screening for glaucoma.

Drug-induced acute angle closure glaucoma

PURPOSE OF REVIEW

Acute angle closure glaucoma is a potentially blinding side effect of a number of local and systemic drugs, including adrenergic, both anticholinergic and cholinergic, antidepressant and antianxiety, sulfa-based, and anticoagulant agents. The purpose of this article is to bring this condition to the attention of clinicians using these compounds as well as ophthalmologists called to see the patient.

RECENT FINDINGS

Acute angle closure glaucoma due to pupillary block, treatable by peripheral iridotomy, can be caused by adrenergic agents, either locally (phenylephrine drops, nasal ephedrine, or nebulized salbutamol) or systemically (epinephrine for anaphylactic shock), drugs with anticholinergic effects including tropicamide and atropine drops, tri and tetracyclic antidepressants, and cholinergic agents like pilocarpine. A novel anticholinergic form is the use of periocular botulinum toxin diffusing back to the ciliary ganglion inhibiting the pupillary sphincter. Sulfa-based drugs (acetazolamide, hydrochlorothiazide, cotrimoxazole, and topiramate) can cause acute angle closure glaucoma by ciliary body edema with anterior rotation of the iris-lens diaphragm. Iridotomy is not effective.

SUMMARY

Most attacks of acute angle closure glaucoma involving pupillary block occur in individuals that are unaware that they have narrow iridocorneal angles. Practitioners using any of the above drugs should be aware of their potential to cause acute angle closure.

The Tajimi Study Report 2

PURPOSE

To determine the prevalence of primary angle-closure glaucoma (PACG), secondary glaucoma (SG), and all glaucoma in a Japanese population as a part of the Tajimi Study.

DESIGN

Population-based epidemiological survey.

PARTICIPANTS

A random sample of residents 40 years or older from Tajimi, Japan.

INTERVENTION

Each subject underwent a screening program comprising an interview and an ophthalmic examination, including Goldmann applanation tonometry, slit-lamp examination, a van Herick test, fundus photography, and a screening visual field (VF) test using frequency-doubling technology. If glaucoma was suspected, the subject was referred for a definitive examination that included slit-lamp examination, gonioscopy, intraocular pressure measurement, a VF test, and optic disc and fundus examination. A diagnosis of PACG or SG was made based on slit-lamp examination, gonioscopy, optic disc appearance, and perimetric results.

MAIN OUTCOME MEASURES

Prevalences of PACG, SG, and all cases of glaucoma.

RESULTS

Of 3870 eligible people, 3021 (78.1%) participated in the study. Estimated prevalences of PACG and SG in those over 40 years were 0.6% (95% confidence interval [CI], 0.4%-0.9%) and 0.5% (95% CI, 0.2%-0.7%), respectively. Prevalences of all glaucoma and glaucoma/suspected glaucoma were estimated to be 5.0% (95% CI, 4.2%-5.8%) and 7.5% (95% CI, 6.5%-8.4%), respectively.

CONCLUSIONS

Prevalences were 0.6%, 0.5%, and 5.0%, respectively, for PACG, SG, and all glaucoma in subjects over 40 years from Tajimi, Japan.

Drug-induced glaucomas: mechanism and management

Glaucoma comprises a heterogeneous group of diseases that have in common a characteristic optic neuropathy and visual field defects, for which elevated intraocular pressure is the major risk factor. The level of intraocular pressure within the eye depends on the steady state of formation and drainage of the clear watery fluid, called the aqueous humour, in the anterior chamber of the eye. An obstruction in the circulatory pathway of aqueous humour causes an elevation in intraocular pressure. Because intraocular pressure is the most modifiable parameter, therapeutic measures (medical and surgical) are aimed at reducing the pressure to protect against optic nerve damage. Glaucomatous optic neuropathy results from degeneration of the axonal nerve fibres in the optic nerve and death of their cell bodies, the retinal ganglion cells. Clinical examination of the optic nerve head or disc and the peripapillary nerve fibre layer of the retina reveals specific changes, and the resulting visual field defects can be documented by perimetry. Glaucoma can be classified into four main groups: primary open-angle glaucoma; angle-closure glaucoma; secondary glaucoma; and developmental glaucoma. Drug-induced glaucoma should be considered as a form of secondary glaucoma because it is brought about by specific systemic or topical medications. Although there is a high prevalence of glaucoma worldwide, the incidence of drug-induced glaucoma is uncertain. Drugs that cause or exacerbate open-angle glaucoma are mostly glucocorticoids. Several classes of drugs, including adrenergic agonists, cholinergics, anticholinergics, sulpha-based drugs, selective serotonin reuptake inhibitors, tricyclic and tetracyclic antidepressants, anticoagulants and histamine H(1) and H(2) receptor antagonists, have been reported to induce or precipitate acute angle-closure glaucoma, especially in individuals predisposed with narrow angles of the anterior chamber. In some instances, bilateral involvement and even blindness have occurred. In this article, the mechanism and management of drug-induced glaucomatous disease of the eye are emphasised. Although the product package insert may mention glaucoma as a contraindication or as an adverse effect, the type of glaucoma is usually not specified. Clinicians should be mindful of the possibility of drug-induced glaucoma, whether or not it is listed as a contraindication and, if in doubt, consult an ophthalmologist.

Prevalence of retinal hemorrhages and child abuse in children who present with an apparent life-threatening event

OBJECTIVE

Child abuse (CA) can present with a spectrum of signs and symptoms. Apparent life-threatening events (ALTEs) may be a subtle presentation of CA. Retinal hemorrhages (RHs) are a well-described finding in some patients with CA. We hypothesized that screening children who present with a chief complaint of an ALTE for RH would detect an otherwise occult presentation of CA.

METHODS

Children who were younger than 24 months of age and presented to the emergency department between March 1, 1997, and February 28, 1999, with signs and symptoms consistent with the National Institutes of Health's definition of an ALTE were studied prospectively. Children were excluded when it was readily apparent on presentation that the child was a victim of CA. Demographic data, a complete blood count with differential, venous blood gas, carboxyhemoglobin level, and urine toxicological screen were collected. A pediatric ophthalmologist performed a dilated funduscopic examination; patients who were found to have RH underwent a noncontrast computerized tomographic scan of the head and skeletal survey to evaluate for occult injury. Evaluations by social services or Children, Youth and Families, the results of all diagnostic tests obtained, and the final discharge diagnosis were recorded. Medical records of all patients were reviewed at 1 year; subsequent visits, hospitalizations, and evaluations by social services or Children, Youth and Families were recorded.

RESULTS

A total of 128 patients presented to the emergency department with an ALTE during the study period. No patients were excluded. Mean age was 2.1 months (median: 1.27; range: 0.07-16.0; standard deviation: 2.1). Fifty-seven (44.5%) were boys; 86 (67.2%) were white, and 36 (27.9%) were black. A total of 26 (20.3%) of 128 patients had a history of an ALTE, 4 (3.4%) of 117 had a family history of an ALTE, and 15 (12.8%) of 117 had a family history of sudden infant death syndrome. Dilated funduscopic examination was performed on 73 (57.0%) of 128 patients; RH was detected in 1 patient (1.4%). Four children, including the patient with RH, underwent an evaluation for suspected abuse; 3 (2.3%) of 128 were determined to have been abused.

CONCLUSIONS

RH was detected in 1 (1.4%) of 73 patients in our population of infants with ALTEs and 1 of 3 patients who were victims of CA and presented with an ALTE. CA was detected in 2.3% of patients who presented with an ALTE. The diagnosis of CA should be seriously considered in patients who present with an ALTE. The evaluation of ALTEs should include funduscopic examination as ALTEs and RHs are associated with CA.

Mydriasis and glaucoma: exploding the myth. A systematic review

AIMS

To investigate the risk of inducing acute glaucoma following mydriasis.

METHODS

Systematic review of published research 1933-1999.

RESULTS

The risk of inducing acute glaucoma following mydriasis with tropicamide alone is close to zero, no case being identified. The risk with long-acting or combined agents is between 1 in 3,380 and 1 in 20,000. The presence of chronic glaucoma constitutes no additional risk.

CONCLUSIONS

Mydriasis with tropicamide alone is safe even in people with chronic glaucoma. It should be advised in all patients when thorough retinal examination is indicated.

Management of diabetic retinopathy by Australian optometrists. Working Group on Evaluation of NHMRC Retinopathy Guideline Distribution. National Health and Medical Research Council

PURPOSE

To describe current practices related to the management of diabetic retinopathy by Australian optometrists.

SETTING AND METHODS

A two-page self-administered questionnaire was mailed to a random sample of 504 Australian optometrists. The survey included questions about the practice (such as size and location); current practice with regard to management of patients with diabetic retinopathy; barriers to use of dilating drops; and a number of patient scenarios related to screening, follow-up and treatment of diabetic retinopathy.

RESULTS

Completed questionnaires were returned by 407 of the 473 eligible optometrists (86%). They had been practising optometry between 1 and 50 years (median 14). Of the 243 optometrists who provided details about the location of their practices, 145 (37%) had at least one of their practices in a rural area. The estimated percentage of patients with diagnosed diabetes ranged from 0.5 to 40% (median = 5.0%). Three-hundred and twenty-two optometrists (79%) reported that they would often or almost always ask new patients over the age of 40 whether they have diabetes. The majority of optometrists (n = 387, 95%) would often or almost always ask their new patients with diabetes about their control of blood glucose levels and the majority of optometrists (n = 330, 81%) would often or almost always tell their patients with diabetes about the importance of strict glucose control in delaying retinopathy. The most common barrier to dilated ophthalmoscopy was patients not wanting to be dilated, with 38.1% of optometrists reporting this to be a moderate or major barrier. The next most common barrier was fear of precipitating angle closure glaucoma; 17.1% of optometrists reported this to be a moderate or major barrier

CONCLUSION

The National Health and Medical Research Council (NHMRC) guidelines for the management of diabetic retinopathy are timely in relation to the expressed desire of Australian optometrists to learn more about management of diabetic retinopathy These data will be used prospectively to assess changes in management of patients with diabetic retinopathy as a result of the release of the NHMRC guidelines.

Glaucoma: diagnosis and management

Glaucoma is the third most prevalent cause of global blindness, accounting for over 5 million blind. It is common in Western Countries; the estimated prevalence of primary open angle glaucoma rises from a total prevalence of 1.1% to approximately 3% of our population as it ages. Ethnicity affects both the risk of developing glaucoma and the outcome. It is an expensive disease both to detect and to treat. Recent scientific advances include elucidation of the genetic mechanism behind the disease and the study of haemodynamic and biochemical co-factors in the development of glaucomatous optic neuropathy, particularly in relation to the pathogenesis of normal tension glaucoma. Several new types of topical medication have recently been developed for use in glaucoma; both the impact of these therapies and their cost effectiveness remain to be evaluated. There are widely differing regimes which effectively treat glaucoma; some ophthalmologists prefer early surgical intervention whilst others reserve surgery for relatively advanced disease. All methods of current treatment rely on the reduction of intra-ocular pressure; as yet there is no medication which has been definitively proven to be either neuroprotective or to influence favourably optic nerve perfusion. Despite this, most sufferers of glaucoma are able to lead lives of quality. Increased community awareness of glaucoma, and earlier detection of the condition, will doubtless result in decreased morbidity due to glaucoma.

Management of patients with narrow angles and acute angle-closure glaucoma

BACKGROUND: Acute closure of the anterior chamber angle can have catastrophic consequences for vision when it occurs in an unsupervised situation. Visual debilitation is much less likely to result when angle-closure occurs in a well-controlled environment that allows appropriate management. Therefore, it is desirable for optometrists to undertake a complete ocular health assessment, including mydriatic fundus examination, on patients who have narrow anterior chamber angles, provided that appropriate precautions and procedures are followed. CASE REPORT: We report on the case of a 59-year-old white female whose anterior chamber angles closed in response to mydriatic drops instilled during an optometric examination. Her optic discs and visual field results from before and four years after the angle-closure attack do not show any significant changes. CONCLUSION: We conclude that the optimal standard of care for patients presenting to an optometric practice, and who are subsequently found to have narrow anterior chamber angles, includes pupillary dilatation to allow stereoscopic visualisation of the optic nerve head. Precautions must be followed to ensure that, in the unlikely event of an ensuing angle-closure episode, the attack occurs under clinically supervised conditions.

Evaluation of screening schemes for eye disease in a primary care setting

BACKGROUND AND PURPOSE

Screening in a primary care setting could be an effective method for detection of eye disease. This study was designed to evaluate a questionnaire and a battery of tests for their performance in eye disease screening at a primary care clinic.

METHODS

405 patients aged 40 years or older were interviewed and received a comprehensive eye examination including visual acuity and visual field testing, tonometry, slit-lamp examination, dilated fundus examination and photography. Sensitivity and specificity for the identification of eye disease were calculated for each test and various combinations of tests.

RESULTS

A questionnaire-based algorithm for detection of overall eye disease was sufficiently sensitive (90%) but less specific (44%) than an ideal screening test. Distance visual acuity with presenting correction of < or = 20/40 had a sensitivity of 61% and specificity of 72%. A dilated fundus examination had a sensitivity of 79% and specificity of 82%. In screening for glaucoma, tonometry was ineffective (sensitivity = 27% and specificity = 96%), while visual field testing by suprathreshold screening had a sensitivity of 70% and specificity of 67%. Among a variety of combinations, a two-stage strategy with the questionnaire as a first-stage and visual acuity and ophthalmoscopy as second-stage tests provided the best balance of sensitivity (83%) and specificity (76%).

CONCLUSION

Among currently available ophthalmic tests, an eye examination including a thorough fundus examination is critical in detection of eye disease. A five-item questionnaire may be useful to identify patients at high risk in primary care practice. More effective tests are needed to improve performance of eye disease screening.

How effective is undergraduate and postgraduate teaching in ophthalmology?

PURPOSE

To gain an insight into the adequacy of ophthalmic medical education for doctors in the primary care setting.

METHODS

A short forced-choice questionnaire was set to 150 randomly selected primary care practitioners in and around Bristol. Information was collected in relation to undergraduate and postgraduate ophthalmic education, ophthalmic confidence, facilities and understanding.

RESULTS

One hundred and thirty-three primary care doctors replied to the questionnaire of whom 35% were fundholders and 47% in training practices. Only 22% of all respondents felt their undergraduate ophthalmic medical education to be adequate. However, 83% of the 86 primary care doctors who had attended postgraduate update courses in ophthalmology felt these to be adequate. Despite the availability of an ophthalmoscope and distance vision chart, only 56% felt confident with the ophthalmoscope and only 61% reported that their distance chart was set up in accord with manufacturer's instructions. Seventy-one per cent of respondents reported having access to dilating agents but only 61% felt confident using them. Understanding of two key ophthalmic terms was also poor. Despite the general satisfaction, attendance of postgraduate update courses did not appear to alter facilities, confidence or understanding.

CONCLUSIONS

It is apparent that most primary care doctors view their undergraduate ophthalmic medical education as inadequate and this is reflected in their confidence and understanding. Postgraduate courses, although more favourably received, do not appear to after these findings. We strongly suggest, therefore that general ophthalmic education is aimed at teaching examination techniques and ophthalmological principles suitable for primary care practice.