Increased incidence of acute primary angle closure during the COVID-19 outbreak in China: A retrospective analysis

This study aimed to investigate the incidence and clinical characteristics of acute primary angle closure (APAC) during the Coronavirus Disease 2019 (COVID-19) pandemic in China. This was a retrospective study of patients diagnosed with APAC in a glaucoma clinic over a 5-year period. We compared the number of APAC cases during the COVID-19 outbreak (December 7, 2022 to January 7, 2023) with those during the same period in previous years and 2 months prior to the outbreak. We also collected data on the demographic and clinical features of APAC patients, such as age, sex, disease course, visual acuity, intraocular pressure (IOP), and lens opacity. We included 95 eyes of 88 patients with APAC were included. Of these, 65 were female and 23 were male. The mean age was 68.0 ± 8.1 years. The median disease course was 10.8 ± 9.5 days. There was a significant increase in the number of APAC cases during the COVID-19 outbreak compared with the same months over a 5-year period (44 vs 51, P < .001). A higher proportion of women developed APAC during the outbreak period than during the non-outbreak period (P < .001). Eyes with APAC in the outbreak period had a lower mean IOP than those in the preceding 6 months (40.5 ± 8.8 mm Hg vs 46.1 ± 10.1 mm Hg; P = .043). No significant differences were observed in disease duration, lens opacity, or bilateral or unilateral onset between the 2 groups. Our study suggests a potential correlation between APAC and COVID-19, marked by a significant surge in APAC cases concurrent with the COVID-19 outbreak. However, the underlying mechanisms and preventive strategies remain to be elucidated.

Low expression of TGF-β2 and matrilin2 in human aqueous humour with acute primary angle closure

Primary angle-closure glaucoma (PACG) is the leading cause of irreversible blindness in the world. Angle closure induced by pupil block and secondary iris synechia is the fundamental pathology of the PACG. The molecular mechanisms of angle closure have not yet been clearly illustrated. This study was designed to investigate the protein difference in the aqueous humour and explore new biomarker of the PACG. Aqueous humour (AH) was collected from patients with acute primary angle closure (APAC) and cataract (n = 10 in APAC group) and patients with cataract only (n = 10 in control group). Samples were pooled and measured using label-free proteome technology. Then, the differentially expressed proteins (DEPs) were verified by ELISA using independent AH samples (n = 20 each group). More than 400 proteins were revealed in both groups through proteomics. Comparing the two groups, there were 91DEPs. These proteins participate in biological activities such as inflammation, fibrosis, nerve growth and degeneration and metabolism. We found that the expression of transforming growth factor-β2 and matrilin2 was downregulated in the APAC group. The two proteins are related to inflammation and extracellular matrix formation, which might be involved in angle closure. This study characterized DEPs in AH of the APAC and found a downregulated protein matrilin2.

Paracentral Acute Middle Maculopathy Following Acute Primary Angle Closure and Acute Primary Angle Closure Glaucoma

Purpose

To report the prevalence, clinical characteristics and risk factors for paracentral acute middle maculopathy (PAMM) following acute primary angle closure (APAC) and acute primary angle closure glaucoma (APACG).

Methods

This retrospective study consecutively recruited patients diagnosed with APAC or APACG. Based on the spectral domain optical coherence tomography characteristics, PAMM eyes were divided into three stages. Characteristics of different stages such as the time from symptoms to treatment (TST), retinal thickness and BCVA improvement were analyzed. The risk factors of PAMM were evaluated by binary logistic regression models.

Results

A total of 781 eyes of 781 APAC or APACG patients were included, and PAMM was found in 22 (2.9%) of them. Stage III eyes had a significantly longer TST than stage I eyes (P = 0.008) while exhibiting significantly thinner retinal thicknesses (P < 0.0001). The BCVA improvement was significantly worse in the eyes treated in stage III than in those treated in stage I (P = 0.008). Older age, longer axial length and without type 2 diabetes were associated with a lower risk of incident PAMM (OR = 0.95, P = 0.028; OR = 0.52, P = 0.019; OR = 3.92, P = 0.022).

Conclusion

PAMM can be secondary to APAC or APACG at a rate of 2.9%. Different visual outcomes were observed in patients who received the intervention at different stages of PAMM. Younger patients with a shorter axial length and type 2 diabetes were found to be more susceptible to PAMM.

The occurrence of acute primary angle closure triggered, aggravated, and accelerated by COVID-19 infection: retrospective observational study

Introduction

The aim of this study is to demonstrate the relevance of primary acute angle closure (APAC) and COVID-19 infection, compare the demographic features and manifestations between COVID-19 positive and negative patients with APAC, and infer the underlying mechanism.

Methods

This study is based on all patients diagnosed with APAC at the glaucoma center of Eye, Ear, Nose and Throat Hospital of Fudan University (Fenyang road center) from 15th December 2022 to 11th January 2023. Totally 171 APAC cases were categorized into COVID-19 positive and negative group. Demographic features and final treatment level of the patients were compared between the two groups. Clinical manifestations, intraocular pressure, and anterior chamber configuration were also compared between the two groups.

Results

In the COVID-19 positive group, the number of cases with APAC onset spiked in 22nd December 2022, which coincided with the spike of COVID-19 antigen positive people. Compared to the COVID-19 negative group, COVID-19 positive APAC patients were younger with a lower percentage of APAC history. Additionally, more eyes of COVID-19 positive APAC patients showed keratic precipitates. COVID-19 positive eyes had significantly larger anterior chamber depth with a more dilated pupil. Therefore, COVID-19 infection could probably act as a triggering factor of APAC.

Discussion

The onset of APAC might be accelerated by COVID-19 infection for patients with younger age and milder anatomical configuration. Additionally, COVID-19 related APAC cases might have a more abrupt and fierce onset. Ophthalmic emergent services should not be neglected during the epidemic period.

Malignant Glaucoma After Immediate Primary Phacoemulsification for Acute Primary Angle Closure: A Case Report

Malignant glaucoma is characterized by ciliary block or aqueous misdirection, shallowing of the anterior chamber with elevated intraocular pressure (IOP), resistance to treatment, and rapid progression to blindness. However, the exact pathogenic mechanism is yet to be established. Here, we report a case of malignant glaucoma caused by immediate primary phacoemulsification for acute primary angle closure (APAC). A 90-year-old woman, who had experienced right eye pain and blurred vision one day prior, had a cataract in the same eye without phacodonesis. The right eye IOP was 39 mmHg, preoperative anterior chamber depth was 1.00 mm, and the axial length was 22.31 mm. We diagnosed APAC in the right eye and performed phacoemulsification. On postoperative day one, the IOP decreased to the normal range (15 mmHg), the anterior chamber deepened, and the angle became open. However, one week after phacoemulsification, the anterior chamber and angle became shallower and closer again. We diagnosed the patient with malignant glaucoma, performed hyaloid-zonulo-iridectomy, and administered 1% atropine eye drops postoperatively. As a result, the IOP was limited to a 10 mmHg range with an open angle and deep anterior chamber. Malignant glaucoma can be caused by immediate primary phacoemulsification for APAC.

Predictors of long-term visual field outcome after an episode of acute primary angle closure

BACKGROUND

To investigate the long-term visual field (VF) outcome and baseline factors associated with functional sequelae in patients who experienced an episode of acute primary angle closure (APAC) and underwent subsequent lens extraction.

METHODS

Fifty patients (50 eyes) who experienced an APAC episode and underwent subsequent lens extraction at Chonnam National University Hospital were enrolled in this retrospective study. Patients underwent VF examinations after 1 year of an acute episode. They were classified into two groups based on whether they had significant VF defects or not. Demographic data were recorded, and baseline anterior-segment OCT (AS-OCT) images were analysed. Multivariate logistic regression analysis was performed to assess baseline risk factors for presence of VF defects.

RESULTS

Twenty-five (50%) eyes were found to have varied degree of VF defects after 1 year of an acute episode. Longer duration between the symptom onset and IOP lowering (p = 0.005), a higher presenting IOP (p = 0.014), and flat iris curvature (p = 0.037) at baseline AS-OCT measurement were significant predictors of VF loss. The area under the receiver operating characteristic curve (AUC) revealed that combination of these three potential baseline factors could predict the long-term VF outcome (AUC = 0.921).

CONCLUSIONS

Patients exhibiting a long duration between symptom onset and IOP lowering, a high presenting IOP, and flat iris curvature were at a higher risk of visual impairment after an episode of APAC. The eyes with such features may require more careful follow-up after an episode of APAC.

Safety and Efficacy of Rapid Primary Phacoemulsification on Acute Primary Angle Closure with and without Preoperative IOP-Lowering Medication

This study aimed to investigate the safety and efficacy of rapid primary phacoemulsification in patients with acute primary angle closure (APAC) (n = 41), with or without preoperative IOP-lowering medication. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of corneal endothelial cells (CECs), and number of IOP-lowering medications at the preoperative examination (Pre), postoperative day 1 (1d), week 1 (1w), and month 1 (1m) were used as indicators and compared. BCVA significantly improved at 1d, 1w, and 1m compared with Pre (p < 0.05) and significantly improved at 1m compared to 1d (p < 0.05) for all eyes. IOP significantly decreased at 1d, 1w, and 1m compared with Pre (p < 0.05). CECs were not significantly different between Pre and 1m; the number of IOP-lowering medications decreased significantly from Pre to 1m (p < 0.05). BCVA and IOP were not significantly different between the two groups for all periods. CECs were not significantly different between the two groups at Pre and 1m. Rapid primary phacoemulsification improved visual acuity due to improvement of corneal edema without central visual field defects and good IOP control without reoperation or IOP-lowering medication and maintained the number of corneal endothelial cells with or without preoperative IOP-lowering medication in patients with APAC.

Clinical presentation of acute primary angle closure during the COVID-19 epidemic lockdown

Purpose

This study aimed to investigate the clinical presentation of acute primary angle closure (APAC) during the COVID-19 epidemic lockdown in Wuhan.

Methods

Consecutive patients seeking APAC treatment at the Wuhan Aier Eye Hospital during the 76 days (January 23-April 8, 2020) when the lockdown policy was implemented due to the COVID-19 pandemic were compared to those during the same period the following year (January 23-April 8, 2021), when the lockdown policy was not implemented. The cohorts were compared to assess demographic variables and clinical presentations.

Results

A total of 54 patients (64 eyes) were included in the 2020, compared with 46 patients (51 eyes) in the 2021. Demographic factors were similar between the groups. Significantly more patients developed blindness in the 2020 cohort (21.87%) than in the 2021 cohort (7.84%). Patients in the 2020 showed a longer time from symptom to treatment (241.84 ± 211.95 h in 2020 vs. 121.53 ± 96.12 h in 2021; P = 0.001), higher intraocular pressure at presentation (52.63 ± 12.45 mmHg in 2020 vs. 45.16 ± 9.79 mmHg in 2021; P = 0.001), larger pupil diameter (5.47 ± 1.62 mm in 2020 vs. 4.33 ± 1.27 mm in 2021; P = 0.001), and more glaucomatous optic neuropathy diagnoses [20/64 eyes (31.25%) in 2020 vs. 7/51 eyes (13.73%) in 2021; P = 0.03].

Conclusion

The time between the onset of APAC symptoms and its treatment during the COVID-19 epidemic lockdown was significantly prolonged, which increased the blindness rate of APAC patients.

Classifications of Qualitative Characteristics on Angle Configurations via Ultrasound Biomicroscopy in Acute Primary Angle Closure

Purpose

To study the classifications of qualitative characteristics on the angle configurations in the acute primary angle closure (APAC) and fellow eyes by ultrasound biomicroscopy (UBM).

Methods

A total of 131 patients (262 eyes) were researched retrospectively. The qualitative parameters from UBM images were classified into iris form (IF), ciliary body configuration (CBC), basal iris thickness (BIT), iris convexity (IC), iris insert (II), iris angulation (IA), ciliary body size (CBS) and ciliary body position (CBP). Comparative analyses between the APAC (case group) and fellow (control group) eyes were performed.

Results

There were significant differences in IF, CBC, IC, II, CBS, CBP between the case group and control group in all quadrants (P<0.001). The IA of the case group and control group presented significant difference in all quadrants (P=0.001). However, there was not a significant difference in BIT between the case group and control group in all quadrants (P=0.495). The case group had fewer parallelogram-like and mushroom-like and more cone-like and hook-like CBCs than the control group (P<0.001).

Conclusion

Multiple ciliary body configurations can influence the stability of the lens and the anatomic configuration of the anterior chamber angle indirectly. New qualitative classification system of UBM may be more intuitionistic and refined to reflect the angle configurations to help clinical practice.

Efficacy of brinzolamide in the initial management of acute primary angle closure: A randomized controlled trial

WHAT IS KNOWN AND OBJECTIVE?: Since comprehensive medication has an important role in the initial management of patients presenting with acute primary angle closure, it is necessary to analyse the effect of each drug on alleviating the disease. This study aimed to evaluate the intraocular pressure-lowering effect of brinzolamide in the sequential treatment of acute primary angle closure. METHODS: In this randomized double-blind controlled trial, a total of 131 eyes of 125 consecutive patients who presented with their first episode of acute primary angle closure were recruited and received sequential treatment. In this treatment, in the absence of remission, anti-glaucoma drugs, anterior chamber paracentesis and argon laser peripheral iridoplasty are used sequentially. The patients were randomized to receive either brinzolamide or normal saline as a placebo. The primary outcomes were decreased intraocular pressure, success rate and treatment time. RESULTS AND DISCUSSION: There was no statistically significant difference in the decreased level of intraocular pressure between the two groups at 6, 12 or 24 h after the start of treatment (p-values were 0.526, 0.206 and 0.130 respectively). The success rate and treatment time were also not significantly different between the groups. No adverse side effects of brinzolamide were observed in the brinzolamide group. WHAT IS NEW AND CONCLUSION?: In patients with a first episode of acute primary angle closure, brinzolamide did not improve the effectiveness of the sequential treatment for reducing the intraocular pressure levels or shortening the treatment time within the first 24 h of initiating therapy.

Inflammatory cytokines levels in aqueous humour and surgical outcomes of trabeculectomy in patients with prior acute primary angle closure

PURPOSE

To quantify the levels of three inflammatory cytokines in the aqueous humour of patients with prior acute primary angle closure (APAC) and investigate their correlation with surgical outcomes of trabeculectomy.

METHODS

In this prospective cohort study, aqueous humour samples were collected from 44 prior APAC eyes. Analyte concentrations of monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) were measured using multiplexed immunoassay kits. Intraocular pressure was measured using Goldmann application tonometry.

RESULTS

Forty-four prior APAC eyes were followed up for 24 months after trabeculectomy and divided into success and failure groups according to surgical outcomes. Monocyte chemoattractant protein-1 (MCP-1) levels in the aqueous humour were significantly higher in the failure group (p = 0.0118). Univariate and multivariate analyses showed that MCP-1 level was a significant risk factor for trabeculectomy outcomes (univariate analysis: p = 0.016, odds ratio = 14.538; multivariate analysis: p = 0.023, odds ratio = 13.718). When prior APAC eyes were divided according to MCP-1 levels, the overall success rate was significantly higher in eyes with low MCP-1 levels than eyes with high MCP-1 levels (p = 0.0249).

CONCLUSION

In prior APAC patients, the MCP-1 level in the aqueous humour predicts trabeculectomy results. Therefore, modulation of MCP-1 expression may have potential clinical applications after filtration surgery.

Seasonal variations and climatic factors on acute primary angle-closure admission in southern China: a 5-year hospital-based retrospective study

PURPOSE

To delineate the seasonality of acute primary angle-closure (APAC) admission in a coastal city of southern China and its association with climatic factors.

METHODS

A total of 1155 Chinese subjects with principal diagnosis of APAC attack were recruited from 2012 to 2016, and their medical records were retrieved. Monthly climatic factors were obtained from the Meteorological Bureau of Shantou. Monthly and seasonal APAC admissions were compared, and its correlation with climatic factors was evaluated.

RESULTS

APAC admission was higher in female subjects (75.9%) with an overall mean age of 64.7 ± 9.3 years. APAC admission was highest in summer with the peak onset in June. The peak of APAC admission for female subjects aged ≤ 65 years was in June, and that for> 65 years was in July. The peak of APAC admission for male subjects aged > 65 years was in August. Precipitation was positively correlated with APAC admission rate for both aged ≤ 65 (β = 0.415, p = 0.001) and > 65 years old (β = 0.364, p = 0.004) female subjects. In contrast, surface temperature was positively correlated with APAC admission rate for male subjects aged > 65 years (β = 0.441, p < 0.001). No climatic factor was correlated with APAC admission rate for male subjects ≤ 65 years.

CONCLUSIONS

This study revealed the peak season of APAC admission in summer, and surface temperature and precipitation are the associated factors. Close monitoring of climate changes could help to reduce the incidence of APAC attack.

Vessel density and retinal nerve fibre layer thickness following acute primary angle closure

BACKGROUND

To evaluate changes in circumpapillary vessel density (cpVD) and retinal nerve fibre layer (cpRNFL) thickness after a successfully treated episode of acute primary angle closure (APAC) and to identify factors associated with glaucoma progression in these eyes.

METHODS

Twenty-six patients successfully treated for a unilateral episode of APAC were included in this prospective study. Optical coherence tomography (OCT) cpRNFL thickness and OCT angiography (OCTA) cpVD were compared between 2 and 8 months after treatment. Multiple logistic regression analysis was conducted to identify factors that influenced cpRNFL outcome.

RESULTS

cpRNFL thicknesses was thinner in the affected eye (94.0 µm (95% CI: 87.3 to 100.8)) than in the unaffected fellow eye (103.1 µm (99.3 to 106.9)) at 2 months (p=0.039). The cpRNFL thickness of the affected eye decreased 8 months after remission (89.5 µm (84 to 95)), but was unchanged in the unaffected eye. Although cpVD was significantly lower (p=0.001) in APAC eyes 2 months after treatment (56.7% (53.8 to 59.7)) compared with fellow eyes (62.9% (61.4 to 64.4)), there was no significant change in cpVD of the affected eye between 2 and 8 months. In the multivariable analysis, the only factor that was associated with cpRNFL progression was lower cpVD at 2 months after APAC remission (OR=1.79, p=0.036).

CONCLUSION

Early reductions of the vessel density and long-term decrease in cpRNFL thickness were observed during the first 8 months after an APAC attack. A lower vessel density at 2 months was the best predictor of conversion to an abnormal cpRNFL thickness. Glaucomatous progression should be suspected in eyes with lower vessel density even after remission of an episode of APAC.

Investigating the neuroprotective effect of Copolymer-1 in acute primary angle closure - Interim report of a randomized placebo-controlled double-masked clinical trial

PURPOSE

To investigate the neuroprotective effect of Copolymer-1 (Cop-1) in patients with acute primary angle closure (APAC) in a randomized double-masked controlled trial.

METHODS

After initial medical management, APAC patients were randomized to receive either subcutaneous Cop-1 or placebo within 24 hr and at 1 week. After laser peripheral iridotomy (LPI), subjects underwent serial visual field (VF) tests and retinal nerve fibre layer (RNFL) thickness measurements with spectral-domain optical coherence tomography. The primary outcome measure was mean number of progressing points (significant slope of ≥ 1 dB per year sensitivity loss) over 16 weeks based on pointwise linear regression analysis, and the secondary outcome measure was the change in RNFL thickness.

RESULTS

Thirty-eight patients (19 in each group) completed the study. Twenty-five (65.8%) were female, the majority being Chinese (86.8%) with mean age 62.5 years (SD 8.1). Patients in the Cop-1 group were found to have mean of 0.32 (SD 0.95) progressing points compared to 2.74 (SD 5.31) in the placebo group (p = 0.09), while 3/19 (15.8%) of Cop-1 treated patients had 1 or more progressing points compared to 7/19 (36.8%) in the placebo group (p = 0.14). There was no difference in change of RNFL thickness between groups (p = 0.57). We found improvement of mean deviation (MD) at week 16 in the Cop-1 group (p = 0.01) compared to worsening of MD in the placebo group (p = 0.04).

CONCLUSION

After APAC, there was no difference in VF progression (or RNFL thickness change) between Cop-1 and placebo groups. However, there was improvement of MD in Cop-1 treated patients.

Combined subconjunctival injection of dexamethasone for the management of acute primary angle closure: a randomised controlled trial

PURPOSE

To investigate whether the combined subconjunctival injection of dexamethasone can accelerate the decrease in intraocular pressure (IOP) in acute primary angle closure (APAC)-affected eyes.

METHODS

42 patients with APAC were recruited for a randomised controlled trial. These patients were separated into two groups: the injection group (21 patients) and the control group (21 patients). The injection group was subjected to a subconjunctival injection with 2.5 mg dexamethasone. Other drug treatments were the same with the control group. The follow-up was at 0, 3, 6, 12 and 24 hours after injection. The outcome measures include IOP and intraocular inflammation variables.

RESULTS

The IOP was significantly decreased in both groups after treatment. However, 24 hours after the initial treatment, the IOP of the injection group was significantly lower compared with the control group (p = 0.017). Kaplan-Meier survival curve analysis showed that the total success rate of the injection group and the control group were 79.7% and 54.9% at 24 hours after treatment (p = 0.027), respectively. For the comparison of anterior chamber inflammation, the severity of conjunctival erythema, ciliary flush and pain in the injection group was also lower than that in the control group at 24 hours after treatment(p = 0.012, p = 0.048 and p = 0.013, respectively). No statistical significance was found between the two groups regarding the anterior chamber cells, anterior chamber flare and photophobia.

CONCLUSION

The combined subconjunctival injection of dexamethasone for the management of APAC eyes can significantly accelerate the relief of high IOP, and therefore, improve the success rate of treatment.

Aqueous humor concentration of VEGF and retinal oxygen saturation after unilateral acute primary angle closure

PURPOSE

To measure the levels of vascular endothelial growth factor (VEGF) in aqueous humor in patients with unilateral acute primary angle closure (APAC) and retinal oxygen saturation (SO2 ) after trabeculectomy.

METHODS

Twelve patients, with unilateral trabeculectomy-required APAC, were recruited as the study group. Aqueous humor samples were collected prospectively for every subject. VEGF concentrations were analysed via enzyme-linked immunosorbent assay (ELISA), and retinal SO2 was measured using oximeter (Reykjavik, Iceland) at 1 month after trabeculectomy.

RESULTS

In the APAC eyes, the mean aqueous humor concentration of VEGF was 388.4 ± 260.1 pg/ml and positively correlated with preoperative intraocular pressure (ρ = 0.658, p = 0.020). In the normal controls, the mean SO2 levels in the larger arterioles and venules were 93.0 ± 5.9% and 59.5 ± 5.4% and the arteriovenous [A-V] difference was 33.5 ± 6.3%. In the study group, the arteriolar SO2 at 1 month after surgery (97.6 ± 19.4%, p = 0.147) did not differ significantly from the values in the control group. However, the mean venular SO2 was significantly lower than the control eyes (50.0 ± 9.1% versus 59.5 ± 5.4%, p = 0.004), and a remarkable increased A-V difference (47.6 ± 22.7% versus 33.5 ± 6.3%) was found in the APAC eyes (p = 0.037).

CONCLUSIONS

Lower venular SO2 and increased A-V difference existed in the APAC eyes after surgery, and it is possible that the saturation was even lower during the attack. Together with the elevated VEGF concentrations in aqueous humor, these provided indirect evidence that ocular hypoxia was constantly present during APAC attack.

Angle parameter changes of phacoemulsification and combined phacotrabeculectomy for acute primary angle closure

AIM

To evaluate the difference in angle parameters and clinical outcome following phacoemulsification and combined phacotrabeculectomy in patients with acute primary angle closure (APAC) using ultrasound biomicroscopy (UBM).

METHODS

Patients (n=23, 31 eyes) were randomized to receive phacoemulsification or combined phacotrabeculectomy (n=24, 31 eyes). Best-corrected visual acuity (BCVA), intraocular pressure (IOP), the main complications following surgery, and indentation gonioscopy and angle parameters measured using UBM were documented preoperatively and postoperatively.

RESULTS

The improvement in BCVA in the phacoemulsification group was significantly greater than in the combined group (P<0.05). IOP in the phacoemulsification group was slightly higher than in the combined group following 1wk of follow-up (P<0.05), whereas there was no significant difference between the two groups at the latter follow-up (P>0.05). Phacoemulsification alone resulted in a slight increase in the trabecular ciliary processes distance compared with the combined surgery (P<0.05), whereas the other angle parameters showed no significant difference between the groups. Complications in combined group were greater than phacoemulsification only group.

CONCLUSION

Both surgeries effectively opened the drainage angle and deepened the anterior chamber, and IOP was well controlled postoperatively. However, phacoemulsification showed better efficacy in improving visual function and showed reduced complications following surgery.

A comparison of two approaches to managing acute primary angle closure in Asian eyes

Purpose

To review the management regimes of acute primary angle closure (APAC) in two hospitals in Singapore, and to identify the incidence of and risk factors for progression to glaucomatous optic neuropathy.

Methods

We conducted a retrospective review of 40 patients from National University Hospital (NUH) and 52 patients from Singapore National Eye Centre (SNEC) who were diagnosed with APAC. Patients were treated with similar protocols of intensive medical therapy until laser peripheral iridotomy could be performed. In the event of failed medical treatment, patients at NUH only underwent laser iridoplasty. The 1-year outcomes were reviewed.

Results

The demographic features of patients and presenting intraocular pressures (IOP) were similar in both centers. More patients from NUH presented within 3 days of symptom onset, compared to those from SNEC (90.0% versus 71.2%, respectively) (P = 0.037). The mean ± standard deviation time to break the attack was 18.2 ± 32.9 hours at SNEC and 9.80 ± 10.6 hours at NUH (P = 0.11). The mean follow up duration was 18.8 ± 14.0 months. Nineteen patients (36.5%) from SNEC and six patients (22.5%) from NUH developed raised IOP (P = 0.032) within 1-year of the attack. Of these, glaucomatous optic neuropathy developed in thirteen patients (68.4%) from SNEC and all six patients (100%) from NUH. At final review, the mean IOP of the APAC eye was 14.8 ± 4.3 mmHg from SNEC and 13.4 ± 3.0 mmHg from NUH. There was no significant difference in final visual acuity or IOP between both groups.

Conclusion

Treatment strategies in both centers were effective in aborting an APAC attack. The development of raised IOP appears to be associated with a longer period of attack suggesting that greater urgency in aborting APAC attacks may entail better long term outcomes.