Long-term outcomes following lens extraction surgery in acute primary angle closure.

BackgroundTo compare the anterior biometrics in eyes with secondary acute angle closure induced by occult lens subluxation (ASAC-LS), misdiagnosed as acute primary angle closure (APAC) at the first visit with APAC, chronic primary angle closure glaucoma (CPACG), and cataract.MethodsThis retrospective case study included 17 eyes with angel closure due to occult LS, who were misdiagnosed as APAC on their first visit, 56 APAC eyes, 54 CPACG eyes, and 56 cataract eyes. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth (AD) and lens thickness (LT) were recorded. Lens position (LP), relative lens position (RLP), corrected lens position (CLP) were calculated. Quantitative data were subject to one-way analysis of variance and correlation analysis. Categorical data were analyzed using the chi-squared test. Receiver operating characteristic (ROC) curves were plotted to obtain a suitable cutoff value of ocular biometrics.ResultsThe ASAC-LS patients had a longer ocular axial length than APAC and CPACG patients. Central corneal thickness of the ASAC-LS patients was not significantly different from APAC patients, but was significantly different from CPACG and cataract patients. The APAC patients had the smallest ACD, while the ASAC-LS patients had the smallest AD. The ASAC-LS patients had the largest lens thickness. According to ROC curve analysis, RLP, ACD, AD, CLP, LP had high power of discrimination.ConclusionsThis study revealed that LS secondary PAC patients had a shallower AD, thicker CCT comparing to those of APAC, CPACG and cataract patients. For patients with acute angle-closure glaucoma, it is necessary to exclude lens zonula relaxation.Trial registrationNCT03752710, retrospectively registered.

Aim: To compare IOP in APAC patients after phacoemulsification compared to LPI. Background: Acute primary angle closure (APAC) is a type of PACG and an important cause of blindness in East Asia. In APAC patients, both LPI and phacoemulsification have been shown to be effective in controlling elevated IOP. Knowledge and information about changes in IOP after phacoemulsification and LPI in APAC patients, which is one of the criteria for successful APAC management, can be a reference as well as a consideration for choosing an effective treatment for APAC patients. Results: Of the 15 articles reviewed, 84% of patients who received phacoemulsification intervention experienced >50% reduction and 24.3% of patients experienced <50% decrease in post-op IOP compared with the mean pre-op IOP. While patients who received LPI intervention, 80.5% of patients experienced >50% reduction in IOP and 19.4% of patients experienced <50% reduction in IOP post-op compared with the mean pre-op IOP. Conclusion: There were decreases in IOP of APAC patients after phacoemulsification or LPI. In addition, there are differences in the decrease in IOP of APAC patients after phacoemulsification compared to LPI. Clinical Significance: Phacoemulsification and LPI are effective for lowering IOP in the early stages of an acute attack. LPI is the preferred procedure according to most guidelines because it is relatively non-invasive, easy to administer on an outpatient basis, and has a lower risk of complications. Phacoemulsificatin has been shown to be a more effective treatment than LPI for IOP reduction in early and medium-term IOP controls.

To determine retinal nerve fiber layer thickness (RNFLT) using Spectral optical coherence tomography/scanning laser ophthalmoscope (Spectral OCT/SLO) in Asian Indian eyes after single, unilateral attack of acute primary angle closure (APAC). Thirty-two patients with unilateral attack of APAC with normal optic disc and normal visual field, unaffected fellow eyes, and 35 age-matched normal control eyes were enrolled for the study. Six weeks after the remission of acute attack, peripapillary average, quadrant, and clock-hour RNFLT were compared between 3 groups using Spectral OCT/SLO. APAC patients had mean IOP of 51.3±13.3 mm Hg (range, 40-74) at the time of presentation with acute attack in the affected eye and 14.9±2.9 mm Hg at 6 weeks after resolution of APAC. Duration of symptoms of acute attack was 35.9±23.8 hours. Significant differences were found between RNFLT in APAC and fellow eyes for most the parameters except for 1, 4, 6, and 7-o'clock-hour sector. Most of the RNFLT parameters showed statistically significant difference between APAC and normal control eyes except for temporal quadrant, 6, 7-o'clock-hour sectors. Statistically significant differences were found between RNFLT in unaffected fellow and normal control eyes for most of the parameters except for 6, 7, 11 o'clock-hour sectors. RNFLT was found to be significantly thinner in APAC and unaffected fellow eyes when compared with normal age-matched controls. Hence, patients with APAC should be monitored carefully to determine its long-term effects on optic disc, RNFLT, and visual fields. Longitudinal studies can determine whether the RNFLT measurements remained stable or showed progression in these patients.

Changes in the RNFL

To develop and validate a Cox regression-based nomogram for predicting blindness in patients with acute primary angle closure(APAC) treated with lens extraction(LE) surgery. This multicenter, retrospective longitudinal study included 254 eyes (217 patients) in the training cohort and 111 eyes (103 patients) from three centers in the validation cohort. Univariate and multivariate Cox regression analyses were performed to identify predictors of blindness. Nomogram performance was assessed using time-dependent receiver operating characteristic(ROC) curves, area under the curve(AUC), concordance index(C-index), and calibration curves. Kaplan-Meier curves were used to compare the blindness incidence between risk groups. Cox regression identified significant predictors of blindness including logMAR visual acuity(VA) at the acute attack(HR, 1.935; 95% CI, 0.966-3.879), use of intravenous mannitol during the acute phase(HR, 0.453; 95% CI, 0.231-0.887), timing of surgery(linear term: HR, 0.771; 95% CI, 0.315-1.887; quadratic term: HR, 0.304; 95% CI, 0.144-0.646; cubic term: HR, 0.792; 95% CI, 0.419-1.498), preoperative logMAR VA(HR, 1.886; 95% CI, 1.174-3.028), and preoperative intraocular pressure(HR, 1.047; 95% CI, 1.022-1.073). The C-index was 0.860 and 0.826 in the training and validation cohorts, respectively. The 1-year and 5-year AUC values were 0.906 and 0.875 in the training cohort, and 0.947 and 0.894 in the validation cohort, respectively. The calibration curves closely follow the ideal diagonal. Kaplan-Meier analysis revealed significant differences in blindness probability between low- and high-risk groups(P < 0.0001). The nomogram provides an effective tool for predicting blindness in APAC patients following LE surgery, enabling risk stratification and aiding clinical decision-making.

To investigate the changes and evaluate the diagnosis value of circumpapillary vessel density (VD) in cases of acute primary angle closure (APAC). Case-control study. APAC patients with a history of unilateral acute attack were enrolled. The eyes with acute episode constituted the case group while the contralateral eyes without attack consisted of the control group. Ophthalmic examinations including slit-lamp examination, best-corrected visual acuity, intraocular pressure and visual field were carried out. Retinal nerve fiber layer (RNFL), macular ganglion cell complex (GCC) were measured by spectral-domain optical coherence tomography, while VD was assessed by optical coherence tomography angiography. The whole en face image vessel density (wiVD), circumpapillary vessel density (cpVD) and inside disk VD for both all vessels and capillary were all significantly lower in the APAC eyes compared to the fellow eyes (P < 0.01 for all). In APAC eyes, the wiVD, inside disk VD and cpVD both for all vessels and capillary were all positively correlated with RNFL and GCC thicknesses but negatively correlated with the mean deviation (MD), pattern standard deviation (PSD) and the duration of acute attack (all P < 0.01). From the ROC curve, the cpVDcap, wiVDcap, cpVDall and wiVDall all showed comparable diagnostic ability with RNFL, GCC and MD to differentiate eyes with APAC from the fellow eyes (all P > 0.05). The inside disk VDcap and VDall demonstrated significant lower diagnostic ability than the cpVDcap, wiVDcap, cpVDall and wiVDall (all P < 0.001). In APAC eyes, circumpapillary VD decreased significantly compared with the fellow unaffected eyes. They were significantly correlated with thicknesses of RNFL and GCC, and visual field MD and PSD in the APAC eyes. The patients with longer duration of acute attack were more likely to have lower cpVD. For APAC, the diagnostic ability of wiVD and cpVD was similar with RNFL, GCC and MD and was higher than inside disk VD.

Acute Primary Angle Closure Structural Damage

Irreversible damage to the optic nerve can follow the rapid increase of IOP during an Acute Primary Angle Closure (APAC). Despite the development of advanced imaging technology, there is still a lack of good longitudinal studies assessing patients after an acute attack. The aim of this study was to assess the progression of patients using different objective optic nerve head and retinal imaging parameters following APAC. Twenty patients with a single attack of APAC, were retrospectively assessed in this study. Patients were assessed with the Heidelberg Retinal Tomography (HRT3) and Scanning Laser Polarimeter (GDx-VCC) as well as Humphrey Visual Field (HVF) repeatedly up to eighteen months after the acute attack. Progression for each imaging modality was assessed with multiple parameters. All patients showed Retinal Nerve Fibre Layer (RNFL) and optic disc changes over time. At 18 months, 67% of patients showed progression in 4/5 GDx parameters, and 33% in all 5. HRT analysis similarly showed progression in 4/5 parameters in 70% of patients, and 30% in all 5. This study shows that structural progressive changes to RNFL and ONH occur following APAC confirming that APAC patients need long-term follow-up after the acute attack.

BackgroundEPO (erythropoietin) and PDGF (platelet derived growth factor) families are thought to be associated with angiogenesis under hypoxic condition. The sharp rise of intraocular pressure in acute primary angle closure (APAC) results in an inefficient supply of oxygen and nutrients. We aimed to measure the expression of EPO and PDGF family members in APAC eyes and demonstrate their associations with APAC’s surgical success rate.MethodsConcentrations of EPO, PDGF-AA, -BB, -CC and -DD collected in aqueous humor samples of 55 patients recruited were measured. Before operations, correlations between target proteins and IOP (intraocular pressure) were detected between APAC (acute primary angle closure) and cataract patients. Based on the post-operative follow-up, the effects of EPO and PDGF family members on the successful rate of trabeculectomy were tested.ResultsThe levels of EPO, PDGF-CC and -DD were significantly elevated in the APAC group compared to the cataract group. During the post-operative follow-up, EPO, PDGF-CC and -DD showed significant differences between the success and failure groups. In multivariable linear regression analyses, failed filtration surgery was more likely in APAC eyes with higher EPO level. The Kaplan-Meier survival plot suggested that the success rate in eyes with low EPO level was significantly higher than that in eyes with high EPO level.ConclusionThe levels of EPO, PDGF-CC and -DD were significantly elevated in failure group. EPO level correlated with preoperative IOP and numbers of eyedrops, and higher EPO level in aqueous humor is a risk factor for trabeculectomy failure. It can be a biomarker to estimate the severity of APAC and the success rate of surgery. The investigation of mechanism of EPO in APAC a may have potential clinical applications for the surgical treatment of APAC.

Acute elevation of intraocular pressure (IOP) in acute primary angle closure (APAC) can cause huge damage to the variable cells in the eye; however, the mechanisms that connect the two processes still remain unclear. In this study, we aim to evaluate the levels of soluble CD44 (sCD44) and vascular endothelial growth factor (VEGF) in the aqueous humour of acute primary angle closure patients. This study included 24 eyes of 24 APAC patients (11 eyes with current APAC and 13 eyes with previous APAC) and 15 eyes of 15 cataract subjects. Clinical data were acquired, and aqueous humour was collected. The levels of sCD44 and VEGF in the aqueous humour were determined by ELISA and magnetic bead immunoassay technique. The concentrations of the sCD44 and VEGF in the current APAC were 9.9 ± 8.8 ng/ml and 2440.2 ± 2107.1 ng/ml, respectively, which were significantly higher when compared to the previous APAC group (p = 0.001) and cataract (p < 0.001); however, there were no significant differences between the group with previous APAC and with cataract. Higher IOP was associated with higher concentration of sCD44 (Rho = 0.617, p = 0.001). The concentration of the VEGF in aqueous humour of APAC patients was closely related to the sCD44 levels (Rho = 0.752, p < 0.001). After acute increase of IOP in the APAC, the level of sCD44 and VEGF increased significantly in the aqueous humour. The damage due to high IOP may therefore be mediated through the release of sCD44.

To investigate features of the anterior segment (AS) of the affected eye compared to the fellow eye within the same patient in acute primary angle closure (APAC). Thirty-six patients with unilateral APAC were imaged with AS optical coherence tomography (OCT) before medical or laser treatment for the acute attack. Anterior chamber depth (ACD), iris curvature (IC), iris thickness at 750 μm from the scleral spur (IT750), lens vault (LV), anterior chamber area (ACA), and iris area were estimated by using ImageJ software (version 1.46). Conditional logistic regression analysis was performed to find the associated factors with the prediction of APAC. When compared to fellow eyes, affected eyes showed significantly shallower ACD (1.90 ± 0.24 and 1.55 ± 0.30 mm, respectively; P < 0.001), smaller ACA (12.96 ± 2.38 and 10.41 ± 2.34 mm(2), respectively; P < 0.001), and greater LV (1.06 ± 0.31 and 1.26 ± 0.36 mm, respectively; P = 0.017). Less IC (odds ratio [OR]*100: 0.935 [95% confidence interval: 0.894, 0.979], P = 0.004) and IT750 (OR*100: 0.904 [0.8294, 0.987], P = 0.024), greater central corneal thickness (OR*100: 2.100 [1.245, 3.542], P = 0.005), greater LV (OR: 66.7 [2.529, 1761.3], P = 0.012), less ACA (OR: 0.386 [0.193, 0.774], P = 0.007), and less ACD (OR*100: 0.912 [0.855, 0.972], P = 0.005) were significantly associated with prediction of APAC. Greater LV was the most prominent feature of affected eyes compared to fellow eyes in APAC patients when assessed by AS OCT. This may play a role in the development of acute attack in primary angle closure.

Changes in Retinal Nerve Fiber Layer After Acute Primary Angle Closure: Reply

This study aimed to compare anterior segment parameters pre-and postoperatively in acute primary angle closure (APAC) and fellow primary angle closure suspect (PACS) eyes using anterior segment optical coherence tomography (AS-OCT) and evaluate the clinical effectiveness of cataract extraction in the treatment of APAC and fellow PACS eyes. Quantitative measurements of various parameters, including anterior chamber depth (ACD), anterior chamber volume (ACV), lens vault (LV), iridocorneal angle contact index (ITCI), iris thickness (IT), iris volume (IV), and iris curvature (IC), were obtained using Tomey CASIA2 AS-OCT on 60 eyes from 30 patients (APAC eyes and their fellow PACS eyes) before and after surgery. Simultaneous analysis of the differences between the APAC eyes and fellow PACS eyes in these parameters, visual acuity (VA), and intraocular pressure (IOP) were performed. After surgery, both the APAC eyes and fellow PACS eyes (a total of 60 eyes) showed a significant increase in ACD and ACV, compared to preoperative measurements. Furthermore, LV and ITCI significantly decreased postoperatively. In the PACS group, IC significantly decreased postoperatively, while there was no statistically significant difference in the APAC group. In the APAC group, there was a significant decrease in IOP and improvement in VA at 1 day, 1 week, and the final follow-up compared to preoperative levels. The IOP values in the PACS group were within the normal range across various time points. VA in the PACS group showed significant improvement at 1 week postoperatively and at the final follow-up compared to preoperative levels. Significant differences of VA were observed in the initial, preoperative, first postoperative day, first postoperative week, and final follow-up, with better outcomes observed in the PACS group compared to the APAC group. Lens extraction surgery can significantly improve anterior segment crowding in APAC and PACS eyes. For APAC eyes, combined cataract extraction with intraocular lens implantation and gonioscopy-assisted goniosynechialysis under direct visualization is feasible and safe. Further, in the fellow PACS eye of APAC patients with either significant or mild cataracts, phacoemulsification can maintain or improve preoperative visual acuity to varying degrees and stabilize IOP.

PurposeTo investigate the corneal endothelial damage caused by acute primary angle closure (APAC) and related risk factors for severe corneal endothelial cell damage in Chinese subjects.MethodsIn this multicentre retrospective study, 160 Chinese patients (171 eyes) diagnosed with APAC were recruited. Endothelial cell density (ECD) and morphological changes short after APAC were studied. Univariate regression and multivariate regression were used to identify risk factors associated with the extent of ECD reduction, including age, gender, education level, patients’ location, systemic diseases, APAC duration (hours), highest recorded intraocular pressure (IOP), and presenting IOP. Factors associated with the probability of severe corneal damage (ECD lower than 1000/mm2) were analysed based on a linear function.ResultsAfter one APAC episode, 12.28% eyes had ECD lower than 1000/mm2, 30.41% had ECD between 1000 and 2000/mm2, and 57.31% had ECD more than 2000/mm2. Attack duration was the only factor associated with severe endothelial damage (p < 0.0001). If the attack were to be subsided within 15.0 h, possibility of ECD lower than 1000/mm2 could be controlled under 1%.ConclusionShortly after the abortion of APAC, 12.28% patients experienced severe endothelial cell damage with ECD less than 1000/mm2. The only factor associated with severe ECD decrease was attack duration. Immediate and effective treatment is pivotal for preserving corneal endothelial function in APAC patients.

Optical Coherence Tomography Measurement of Retinal Nerve Fiber Layer After Acute Primary Angle Closure With Normal Visual Field