Phacoemulsification and intraocular lens implantation for acute angle closure not treated or previously treated by laser iridotomy

Phacoemulsification versus Laser Peripheral Iridotomy for Treating Primary Angle Closure Glaucoma: A Systematic Review and Meta-Analysis

Background

Primary Angle Closure Glaucoma (PACG), is caused by narrowing the iridocorneal angle and increases the risk of blockage in the trabecular meshwork. Phacoemulsification and laser peripheral iridotomy (LPI) effectively control IOP elevation and widen the angle. This systematic review and meta-analysis compared Phacoemulsification and LPI Effectiveness for PACG.

Methods

We searched Medline, Embase, and CENTRAL. We included randomized controlled trials (RCTs) that compared Phacoemulsification and LPI for individuals with PACG. We sought to evaluate the following outcomes: mean IOP, number of glaucoma medications, visual acuity (VA), visual field (VF) progression, peripheral anterior synechiae (PAS), Shaffer gonioscopy grading, central corneal thickness (CCT), central endothelial cell density (CECD), and poor response to surgery. The standardized mean difference (SMD) was used to represent continuous outcomes, while the risk ratio (RR) was used to represent dichotomous outcomes.

Results

5 RCTs that enrolled 917 participants were deemed eligible. The phacoemulsification group showed statistically significance lower mean CCT and CECD and lower risk of poor response to surgery compared to LPI (SMD = -1.10; 95% -1.50, -0.70; P<0.001, SMD -366.12; 95% -652.59, -79.65; P=0.01, and RR 0.35; 95% 0.23, 0.54; P<0.001 respectively). There were no significant improvement in IOP and number of medications between both groups (SMD = -0.74; 95% CI = -2.26, 0.78; P=0.34, and SMD -17.58; 95% CI = -50.28, 15.12; P=0.29 respectively). Finally, there were also no significant differences in VA, VF progression, PAS, and mean Shaffer gonioscopy grading between both groups.

Conclusion

Phacoemulsification showed statistically significant lower mean corneal thickness, central endothelial cell density, and lower risk of poor response to surgery compared to LPI. However, there were no significant differences in mean IOP, number of medications, VA, VF progression, PAS, and mean Shaffer gonioscopy grading between Phacoemulsification and LPI.

Intraocular pressure profile following selective laser trabeculoplasty in pigmentary and primary open-angle glaucoma

PURPOSE

To compare the intraocular pressure (IOP) profile and the incidence of IOP spikes following selective laser trabeculoplasty (SLT) between pigmentary glaucoma (PG) and primary open-angle glaucoma (POAG).

MATERIALS AND METHODS

Retrospective comparative study of 65 PG eyes of 51 patients matched with 65 POAG eyes of 65 patients who received SLT. Matching was done based on age, gender, glaucoma severity, pre-laser IOP, and number of medications. Post-SLT IOP spike was defined as IOP elevation ≥5mmHg, 30-45 min after the laser.

RESULTS

In PG and POAG groups, the average age was 62.33 ± 9.18 and 62.58 ± 9.19 years (p = 0.95). The glaucoma severity (p = 0.708), baseline IOP (PG = 21.61 ± 1.34mmHg vs. POAG = 21.13 ± 5.09mmHg, p = 0.943), and number of topical glaucoma medications(PG = 2.34 ± 1.34 vs. POAG = 2.1 ± 1.41, p = 0.342) were comparable. More PG patients were on oral acetazolamide (PG = 26.15% vs. POAG = 1.5%, p < 0.001). Average logMAR visual acuity was significantly higher in the POAG group (0.207 ± 0.3 vs. 0.192 ± 0.37, p = 0.012). Eyes with PG received lower laser energy (POAG = 63.65 ± 22.03 mJ vs. PG = 43.71 ± 25.68 mJ, p < 0.001). IOP spikes were recorded in 5 PG eyes (7.6%) and none in the POAG group (p = 0.058). Failure rates were similar (PG = 50.7% and POAG = 43.1%, p = 0.205). In multivariable analysis, only pre-laser IOP (coefficient = 2.154 [CI: 0.765-3.543], p = 0.003) was a significant predictor of IOP change percentage after 12 months.

CONCLUSIONS

SLT was comparably effective in both PG and POAG. IOP spikes were observed only in the PG group, though the total laser energy was lower in this group compared with POAG.

Refractive outcomes after immediate primary phacoemulsification for acute primary angle closure

This study investigated the refractive outcomes of 64 eyes overall including 32 immediate primary phacoemulsification in acute primary angle closure (APAC) eyes and 32 of their fellow eyes. We investigated best-corrected visual acuity, intraocular pressure (IOP), average keratometric diopter (K), spherical equivalent, axial length (AL), central corneal thickness, and anterior chamber depth (ACD) at preoperative examination (Pre) and more than 1-month post-phacoemulsification (1 m), and changes in values. Using SRK/T, Barrett Universal II (Barrett), Hill-Radial Basis Function Version 3.0 (RBF 3.0), and Kane formulas, we calculated and compared refractive prediction error (PE), absolute value of PE (AE), and changes in K, AL, and ACD from Pre to 1 m between APAC and fellow eyes. From Pre to 1 m, K remained similar in APAC and fellow eyes (p = 0.069 and p = 0.082); AL significantly decreased in APAC and in fellow eyes (both p < 0.001); and ACD significantly increased in APAC and in fellow eyes (both p < 0.001). The change in AL differed significantly between the two groups (p = 0.007). Compared to the fellow eyes, PE with SRK/T and Barret formulas (p = 0.0496 and p = 0.039) and AE with Barrett and RBF 3.0 formula (p = 0.001 and p = 0.024) were significantly larger in the APAC eyes. Thus, attention should be paid to refractive prediction error in immediate primary phacoemulsification for APAC eyes caused by preoperative AL elongation due to high IOP.

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.

Three-Year Outcomes of Immediate Primary Phacoemulsification on Acute Primary Angle Closure Eyes and the Fellow Eyes

Purpose

This study investigated the long-term outcomes (> 3 years) of immediate primary phacoemulsification in eyes with acute primary angle closure (APAC) and in the fellow eyes with shallow anterior chamber to prevent APAC development.

Patients and Methods

This is a retrospective study of phacoemulsification for APAC using bilateral eyes. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), and number of IOP-lowering medications at the preoperative examination (Pre), postoperative month 1 (1m), year 3 (3y), and last visit were compared between 14 eyes with APAC and their 14 fellow eyes. The number of corneal endothelial cells (CECs) at Pre and at more than 2 weeks after phacoemulsification was compared. The visual field mean deviation (MD) within 1 year after phacoemulsification and at the last visit was also compared.

Results

For APAC eyes, BCVA was significantly improved at 1m, 3y, and at the last visit as compared with Pre (p < 0.05). IOP significantly decreased at 1m, 3y, and at the last visit compared with Pre (p < 0.05). IOP-lowering medication use decreased significantly from Pre to 1m (p < 0.05). The number of CECs was not significantly different between Pre and more than 2 weeks after phacoemulsification. BCVA was significantly worse in APAC eyes than in fellow eyes at Pre (p < 0.05). IOP and the number of IOP-lowering medications were significantly higher in APAC eyes than in fellow eyes at Pre (p < 0.05).

Conclusion

Primary phacoemulsification improved visual acuity for APAC eyes and maintained good IOP control without the need for reoperation. Moreover, it preserved the number of CECs for the APAC and fellow eyes in the long term.

Lens extraction versus laser peripheral iridotomy for acute primary angle closure

BACKGROUND

Acute primary angle closure (APAC) is a potentially blinding condition. It is one of the few ophthalmic emergencies and carries high rates of visual morbidity in the absence of timely intervention. Laser peripheral iridotomy (LPI) has been the standard of care thus far. However, LPI does not eliminate the long-term risk of chronic angle closure glaucoma and other associated sequelae. There has been increasing interest in lens extraction as the primary treatment for the spectrum of primary angle closure disease, and it is as yet unclear whether these results can be extrapolated to APAC, and whether lens extraction provides better long-term outcomes. We therefore sought to evaluate the effectiveness of lens extraction in APAC to help inform the decision-making process.  OBJECTIVES: To assess the effect of lens extraction compared to LPI in the treatment of APAC.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2022, Issue 1), Ovid MEDLINE, Ovid MEDLINE E-pub Ahead of Print, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily (January 1946 to 10 January 2022), Embase (January 1947 to 10 January 2022), PubMed (1946 to 10 January 2022), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to 10 January 2022), ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search. We last searched the electronic databases on 10 January 2022.

SELECTION CRITERIA

We included randomized controlled clinical trials comparing lens extraction against LPI in adult participants ( ≥ 35 years) with APAC in one or both eyes.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology and assessed the certainty of the body of evidence for prespecified outcomes using the GRADE approach.

MAIN RESULTS

We included two studies conducted in Hong Kong and Singapore, comprising 99 eyes (99 participants) of predominantly Chinese origin. The two studies compared LPI with phacoemulsification performed by experienced surgeons. We assessed that both studies were at high risk of bias. There were no studies evaluating other types of lens extraction procedures.  Phacoemulsification may result in an increased proportion of participants with intraocular pressure (IOP) control compared with LPI at 18 to 24 months (risk ratio (RR) 1.66, 95% confidence interval (CI) 1.28 to 2.15; 2 studies, n = 97; low certainty evidence) and may reduce the need for further IOP-lowering surgery within 24 months (RR 0.07, 96% CI 0.01 to 0.51; 2 studies, n = 99; very low certainty evidence). Phacoemulsification may result in a lower mean IOP at 12 months compared to LPI (mean difference (MD) -3.20, 95% CI -4.79 to -1.61; 1 study, n = 62; low certainty evidence) and a slightly lower mean number of IOP-lowering medications at 18 months (MD -0.87, 95% CI -1.28 to -0.46; 1 study, n = 60; low certainty evidence), but this may not be clinically significant. Phacoemulsification may have little to no effect on the proportion of participants with one or more recurrent APAC episodes in the same eye (RR 0.32, 95% CI 0.01 to 7.30; 1 study, n = 37; very low certainty evidence). Phacoemulsification may result in a wider iridocorneal angle assessed by Shaffer grading at six months (MD 1.15, 95% CI 0.83 to 1.47; 1 study, n = 62; very low certainty evidence). Phacoemulsification may have little to no effect on logMAR best-corrected visual acuity (BCVA) at six months (MD -0.09, 95% CI -0.20 to 0.02; 2 studies, n = 94; very low certainty evidence). There was no evidence of a difference in the extent of peripheral anterior synechiae (PAS) (clock hours) between intervention arms at 6 months (MD -1.86, 95% CI -7.03 to 3.32; 2 studies, n = 94; very low certainty evidence), although the phacoemulsification group may have less PAS (degrees) at 12 months (MD -94.20, 95% CI -140.37 to -48.03; 1 study, n = 62) and 18 months (MD -127.30, 95% CI -168.91 to -85.69; 1 study, n = 60).  In one study, there were 26 adverse events in the phacoemulsification group: intraoperative corneal edema (n = 12), posterior capsular rupture (n = 1), intraoperative bleeding from iris root (n = 1), postoperative fibrinous anterior chamber reaction (n = 7), and visually significant posterior capsular opacification (n = 5), and no cases of suprachoroidal hemorrhage or endophthalmitis. There were four adverse events in the LPI group: closed iridotomy (n = 1) and small iridotomies that required supplementary laser (n = 3). In the other study, there was one adverse event in the phacoemulsification group (IOP > 30 mmHg on day 1 postoperatively (n = 1)), and no intraoperative complications. There were five adverse events in the LPI group: transient hemorrhage (n = 1), corneal burn (n = 1), and repeated LPI because of non-patency (n = 3).  Neither study reported health- or vision-related quality of life measures.

AUTHORS' CONCLUSIONS

Low certainty evidence suggests that early lens extraction may produce more favorable outcomes compared to initial LPI in terms of IOP control. Evidence for other outcomes is less clear. Future high-quality and longer-term studies evaluating the effects of either intervention on the development of glaucomatous damage and visual field changes as well as health-related quality of life measures would be helpful.

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.

Comparison of Laser Iridotomy and Lensectomy Outcomes for Acute Primary Angle Closure

Purpose

To compare the clinical outcomes of the different treatments for acute primary angle closure (APAC).

Methods

We retrospectively reviewed the clinical charts of 87 eyes of 87 patients undergoing treatment for APAC. We investigated the best spectacle-corrected visual acuity (BSCVA), intraocular pressure (IOP), corneal endothelial cell density (ECD), and secondary interventions after each treatment.

Results

The pretreated IOP was 56.4 ± 9.0 mmHg. As the first treatment for APAC, all eyes underwent topical 2% pilocarpine and systemic mannitol administration. Subsequent laser iridotomy (LI) and lensectomy were necessary in 29 eyes (33%) and 35 eyes (40%), respectively. Bullous keratopathy developed in 1 eye (1%), and following glaucoma surgery was required in 7 eyes (8%). The BSCVA at the final follow-up was 0.16 ± 0.53 and 0.01 ± 0.20 logMAR (Mann–Whitney U test, p=0.149), the IOP was 12.8 ± 2.6, and 12.6 ± 2.9 mmHg (p=0.860), and the ECD was 2295.9 ± 658.2 and 2244.1 ± 622.0 cells/mm² (p=0.735) in the LI and lensectomy groups, respectively.

Conclusions

Approximately 26% of eyes with APAC were resolved after the initial medical treatment, and subsequent surgical treatments, such as LI and lensectomy, were required in 33% and 40% of eyes, respectively. We found no significant differences in the BSCVA, the IOP, or the ECD among LI and lensectomy treatment groups.

Central Pars Plana Vitrectomy + Phacoemulsification + Intraocular Lens Implantation in Patients with Small Eyes, Cataract, and Narrow Anterior Chambers

Purpose

To evaluate the results of central pars plana vitrectomy + phacoemulsification + intraocular lens implantation in patients with small eyes, cataract, and narrow chambers.

Methods

This prospective study was carried out in 89 eyes of 58 patients undergoing central pars plana vitrectomy + phacoemulsification + IOL implantation in small eyes with cataract at Clínica La Luz Eye Institute in Lima, Peru.

Results

The mean best corrected visual acuity (BCVA) was 0.8±0.6 preoperatively, 0.5±0.6 at 1 month, 0.3±0.3 at 6 months, 0.1±0.1 at 9 months, and 0.05±0.1 at 1 year, which was statistically significant from the preoperative period to 1 year of follow-up. Mean intraocular pressure was 22.09±2.4 mmHg preoperatively, 14.55±2.9 mmHg at 1 day, 12.94±2.04 mmHg at 1 month, 12.01±1.2 mmHg at 6 months, 12.20±1.9 mmHg at 9 months, and 11.34±1.1 mmHg at 1 year. The reduction in the intraocular pressure from the preoperative control period to the follow-up at 1 year was statistically significant. There was only one complication, a rupture of the posterior capsule, which was quickly resolved.

Conclusion

Central pars plana vitrectomy with phacoemulsification is a safe and effective technique to perform in narrow chambers with all types of cataracts, in experienced hands, which can avoid intraoperative complications.

Efficacy and safety of phacoemulsification plus goniosynechialysis and trabectome in patients with primary angle-closure glaucoma

We evaluated the efficacy and safety of combined phacoemulsification, intraocular lens implantation, goniosynechialysis (GSL), and trabectome in patients with primary angle-closure glaucoma (PACG). Twenty patients (22 eyes) of PACG treated with combined phacoemulsification, intraocular lens implantation, GSL, and trabectome between September 2017 and September 2020 were included in this case series study. The intraocular pressure (IOP), number of glaucoma medications, and best-corrected visual acuity (BCVA) were recorded at baseline, 1, 3, 6, and 12 months after surgery. Successful surgery was defined as IOP < 21 mmHg with or without IOP-lowering medications. IOP was decreased significantly from 22.07 ± 6.62 mmHg at baseline to 15.06 ± 3.39 mmHg at 12 months' follow-up (p = 0.001). The number of glaucoma medications was significantly reduced from 2.68 ± 1.17 preoperatively to 0.78 ± 0.73 at 12 months' follow-up (p < 0.01). The rate of successful surgery was 88.9% at 12 months. The reduction in IOP showed a positive correlation with baseline IOP (p < 0.001), and the reduction in number of glaucoma medications was positively correlated with baseline number of glaucoma medications (p < 0.001). There were no vision-threatening complications intraoperatively or postoperatively. Combined phacoemulsification, IOL implantation, GSL, and trabectome were effective and safe in PACG patients in this study. These combined surgical techniques may be useful in PACG patients, especially those with long term and extensive peripheral anterior synechiae.

Matched Cohort Study of Cataract Surgery With and Without Trabecular Microbypass Stent Implantation in Primary Angle-Closure Glaucoma

PURPOSE

To compare 1-year outcomes of phacoemulsification alone (phaco-only) vs phacoemulsification with implantation of 2 trabecular microbypass stents (iStent or iStent inject; phaco-stent) in eyes with primary angle-closure glaucoma (PACG).

DESIGN

Retrospective matched clinical cohort study.

METHODS

PACG eyes that underwent phaco-only vs phaco-stent at a single ophthalmology center. Groups were matched for baseline intraocular pressure (IOP) and medication use with a tolerance of ±2 mm Hg and ±1 medication, respectively. Primary outcomes included postoperative change in the mean IOP and medications. One-year outcomes were assessed using generalized estimating equations corrected for baseline intergroup differences.

RESULTS

One hundred fifty-eight eyes (79 per group) were included. At 1 year, IOP decreased by 13% (from 16.8 ± 3.1 mm Hg preoperatively) in the phaco-only group (P < .001) and by 27% (from 17.6 ± 3.2 mm Hg) in the phaco-stent group (P < .001). Medication use decreased by 11% (from 1.8 ± 1.3 medications preoperatively) in the phaco-only group (P < .001) and by 46% (from 2.2 ± 1.2 medications) in the phaco-stent group (P < .001). The phaco-stent group experienced significantly larger reductions in IOP and medications compared with the phaco-only group (P < .001). The incidence of IOP spikes was significantly greater in the phaco-only group (18%) compared with the phaco-stent group (4%; P = .005). Safety was favorable with few transient postoperative adverse events.

CONCLUSION

The results of this study highlight that phacoemulsification with implantation of 2 trabecular microbypass stents is more effective and possibly more protective than phaco-only in PACG eyes, as evidenced by significantly larger IOP and medication reductions and smaller incidences of IOP spikes among the phaco-stent eyes.

Combined treatment of phacoemulsification and single-port limited pars plana vitrectomy in acute angle-closure glaucoma

AIM

To evaluate the efficacy of combined treatment of phacoemulsification (PE) and micro-incisional single-port transconjunctival limited pars plana vitrectomy (PPV) in acute angle-closure glaucoma (AACG).

METHODS

A retrospective study included 26 patients who underwent PE diagnosed with AACG. Among them, 16 patients (16 eyes) underwent PE alone, 10 patients (10 eyes) underwent combined limited vitrectomy and PE. Then we compared intraocular pressure (IOP), anterior chamber angle, anterior chamber depth, central corneal thickness and corneal endothelial cell count before and after surgery, and effective PE time during cataract surgery.

RESULTS

Effective PE time was shorter in the combined surgery group than in the single surgery group (P=0.040). There was no statistically significant difference in IOP and best-corrected visual acuity between the two groups postoperatively. At 6mo postoperatively, there was no difference in the anterior chamber angle, anterior chamber depth, and central corneal thickness between two groups, but corneal endothelial cell count was higher in the combined surgery group than in the single surgery group (P=0.046). No complication such as vitreoretinal disease, endophthalmitis, bullous keratopathy was noted.

CONCLUSION

Combined micro-incisional single-port transconjunctival limited PPV and PE are more effective and safer than PE alone because of less operation time and fewer complications for management of AACG.

Clinical Features and Efficacy of Lens Surgery in Patients with Lens Subluxation Misdiagnosed as Primary Angle-Closure Glaucoma

PURPOSE

To investigate the clinical features and efficacy of lens surgery in patients with lens subluxation misdiagnosed as primary angle-closure glaucoma.

METHODS

In total, 2054 inpatients with primary angle-closure glaucoma were consecutively recruited. Eighty-five of the patients were rediagnosed as lens subluxation following ultrasound biomicroscopy after hospitalization. Lens surgeries were performed in all patients, and 35 had a follow-up of at least 12 months. Risk factors of postoperative intraocular pressure control were identified with multivariate logistic regression analysis.

RESULTS

Eighty-five inpatients (4.1%, 85/2054) with lens subluxation were misdiagnosed as primary angle-closure glaucoma, of which 71.8% (2.97% of all cases, 61 out of 2054 subjects) had ocular blunt trauma and 18.8% (0.78% of all cases, 16 out of 2054 subjects) had spontaneous dislocation. Lens surgery significantly decreased the intraocular pressure and improved best-corrected visual acuity, meanwhile increased the anterior chamber depth (all P < 0.001). Postoperatively, the intraocular pressure was controlled with antiglaucomatous eye drops administration in 17 eyes, in which greater range of preoperative angle closure and zonular dialysis, and longer operation time delay were detected. Risk factors for poor postoperative IOP control were more quadrants of angle closure (P = 0.038) and operation time delay (P = 0.045).

CONCLUSION

Lens subluxation was the major cause of the misdiagnosed cases as primary angle-closure glaucoma. Misdiagnosed patients could benefit from the lens surgery, while more angle-closure quadrants and operation time delay indicated worse postoperative intraocular pressure control.

Acute primary angle closure-treatment strategies, evidences and economical considerations

Acute primary angle closure requires emergency management that involves a rapid lowering of the intraocular pressure and resolution of relative pupil block - the most common mechanism of angle closure. Emergency strategies for lowering intraocular pressure include medical treatment and argon laser peripheral iridoplasty. Anterior chamber paracentesis and diode laser transcleral cyclophotocoagulation may be considered in special situations. Relative pupil block can be relieved by peripheral laser iridotomy and primary lens extraction; the latter is a more effective treatment according to the results of clinical trials. However, primary lens extraction can be technically demanding in the acute setting. Peripheral laser iridotomy has a role in relieving pupil block and should also be considered in most cases. Lens extraction may be combined with procedures such as goniosynechialysis, trabeculectomy or endoscopic cyclophotocoagulation. In this review, we aim to discuss the available evidence regarding the different treatment modalities. We also discuss the economic consideration, including cost-effectiveness and life expectancy, in the management of acute primary angle closure.

Surgical peripheral iridectomy via a clear-cornea phacoemulsification incision for pupillary block following cataract surgery in acute angle closure

Background

To describe a technique of surgical peripheral iridectomy via a clear-cornea tunnel incision to prevent or treat pupillary block following phacoemulsification.

Methods

Description of technique and retrospective description results in 20 eyes of 20 patients with acute angle closure with coexisting visually significant cataract undergoing phacoemulsification considered at risk of postoperative papillary block as well as two pseudo-phakic eyes with acute postoperative pupillary-block. Following phacoemulsification and insertion of an intraocular lens, a needle with a bent tip was inserted behind the iris through the corneal tunnel incision. A blunt iris repositor was introduced through the paracentesis and placed above the iris to exert posterior pressure and create a puncture. The size of the puncture was enlarged using scissors. For postoperative pupillary block the same technique was carried out through the existing incisions created for phacoemulsification.

Results

Peripheral iridectomy was successfully created in all 22 eyes. At a mean follow-up of 18.77 ± 9.72 months, none of the iridectomies closed or required enlargement. Two eyes had mild intraoperative bleeding and one eye a small Descemet’s detachment that did not require intervention. No clinically significant complications were observed. Visual acuity and IOP improved or was maintained in all patients. The incidence of pupillary block in our hospital was 0.09% overall, 0.6% in diabetics and 3.5% in those with diabetic retinopathy.

Conclusions

This technique of peripheral iridectomy via the cornea tunnel incision can be safely used during phacoemulsification in eyes at high risk of pupillary block or in the treatment of acute postoperative pupillary-block after cataract surgery. The technique is likely to be especially useful in brown iris, or if a laser is not available.

The role of lens extraction in the current management of primary angle-closure glaucoma

PURPOSE OF REVIEW

Lens extraction for primary angle-closure glaucoma (PACG) is a subject of increased interest recently, with advocates promoting its benefits of anatomical opening of the angle, intraocular pressure (IOP) reduction and improved vision. The present review seeks to evaluate recent available evidence to provide clarity on this potential intervention within the armamentarium of approaches for PACG.

RECENT FINDINGS

The emergence of recent case-control studies, cohort studies and randomized controlled trials has provided a stronger evidence base to equip ophthalmic surgeons with the necessary information to utilize lens extraction in the management of PACG, and to consider whether this should be combined with trabeculectomy or goniosynechialysis. Imaging modalities such as anterior segment optical coherence tomography have yielded new insights into the mechanical features of the lens in angle closure, with the lens thickness and lens vault now quantifiable. A trend is emerging regarding the improvement in IOP control, reduced complication rates and reduced need for IOP-lowering medications in patients who undergo lens extraction for PACG. These issues are discussed, along with aspects of preoperative assessment and surgical techniques.

SUMMARY

Good outcomes in terms of long-term IOP control have been found following lens extraction for PACG. Lens extraction should be considered in patients with PACG, especially with hyperopia, or a thick and anteriorly vaulted lens.

Results of Ahmed glaucoma valve implantation in primary congenital glaucoma

PURPOSE

To evaluate the outcome of Ahmed glaucoma valve (AGV) implantation in primary congenital glaucoma (PCG).

METHODS

The medical records of patients with PCG refractory to trabeculotomy and medical therapy who had undergone AGV implantation with a minimum follow-up of 6 months were retrospectively reviewed. The primary outcome measure was cumulative probability of success, defined as intraocular pressure (IOP) of 6-21 mm Hg, with or without medication, and no serious complications, additional glaucoma surgery, or loss of light perception.

RESULTS

A total of 33 eyes of 22 children with a mean age (and standard deviation) of 2.7 ± 3.1 years were included. The patients had a mean follow-up time of 32.6 ± 18.3 months. The mean IOP was 32.8 ± 7.3 mm Hg preoperatively and 16.8 ± 4.0 mm Hg postoperatively. The number of glaucoma medications was 2.5 ± 0.7 preoperatively and 2.2 ± 0.7 postoperatively. The cumulative probability of success (and standard error) was 97% ± 3.0% in the 1st year, 85% ± 7.0% in the 2nd year, and 56% ± 14.8% in the 5th year. When only the first operated eye per patient was included, the cumulative probability of success was 96% ± 4.4% in the 1st and the 2nd years and 72% ± 15.3% in the 5th year. Major complications comprised tube-endothelial touch (3 eyes), cataract (2 eyes), shunt extrusion (1 eye), and retinal detachment (1 eye).

CONCLUSIONS

AGV implantation in patients with PCG offers moderate success in controlling the IOP with a low rate of complications. Most continued to require medications.

Laser iridotomy and the corneal endothelium: a systemic review

This study aims to systemically review the effect of laser iridotomy on the corneal endothelium. Searches were performed for studies that either compared corneal endothelial cell density/count, corneal thickness and morphology pre- and postiridotomy, or evaluated the postiridotomy development of corneal decompensation. There were 26 eligible studies. Our review shows that the effect of laser iridotomy on the corneal endothelium has been investigated with varying results. Although it has been demonstrated to be a relatively safe procedure, there is still the potential long-term risk of corneal decompensation, for which a corneal transplantation may be indicated eventually. The longest interval between laser iridotomy and corneal decompensation reported was 8 years. Mechanisms proposed for endothelial damage include direct focal injury, thermal damage, mechanical shock waves, iris pigment dispersion, transient rise in intraocular pressure, inflammation, turbulent aqueous flow, time-dependent shear stress on endothelium, chronic breakdown of blood-aqueous barrier and damage from bubbles that settled onto the endothelium. Inherent risk factors identified were iridotrabecular contact, current or prior acute angle closure, pigmented irides, small iris-to-endothelium distance, pre-existing endothelial disease and diabetes. Intervention-related risk factors include laser type, delivery and quantity. The significance of the risk factors and their direct association with the development of corneal decompensation remain to be determined. Understanding these risk factors may allow physicians to counsel their patients better. They may offer opportunities for preventive strategies, allowing us to ensure that a procedure performed to prevent disease progression and visual loss does not cause further morbidity.

[Demographic evolution of acute primary angle closure between 2001-2003 and 2008-2010: impact of modern cataract surgery]

PURPOSE

To study the demographic evolution of acute primary angle closure.

MATERIALS AND METHODS

Retrospective study of patients with acute primary angle closure treated between 2001-2003 and 2008-2010. For each period, a comparison was made of demographic data (number of cases, age at diagnosis, sex), clinical data (biometry, presence or absence of iris plateau or cataract) and therapeutic data (iridotomy, phacoemulsification, trabeculectomy).

RESULTS

Fifty-two cases of acute primary angle closure were treated in the University Hospital of Nantes, France: 34 eyes in 2001-2003 and 18 in 2008-2010, representing a decrease of 47% in acute primary angle closure cases in 7years. The incidence of acute primary angle closure attacks significantly decreased from 0.0596% in 2001-2003 to 0.0224% in 2008-2010. Acute angle closure attacks secondary to cataract decreased significantly from 82% in 2001-2003 to 50% in 2008-2010. In cataractous cases with ocular hypertension persisting after peripheral iridotomy, cataract extraction was performed. Early phacoemulsification less than 10days was significantly more common in 2008-2010 than in 2001-2003 (40% versus 10%).

CONCLUSION

This study confirms the recent decrease in acute primary angle closure attacks. The consistent increase in cataract surgery in the elderly has probably played a preventive role, since the highest decrease in acute primary angle closure cases was observed among the 70-80-year-old population. Recently, acute primary angle closure cases are less often due to cataract than to primary pupillary block or iris plateau. The prevention of acute primary angle closure by gonioscopic monitoring in patients at risk is indispensable.

Conventional and emerging treatments in the management of acute primary angle closure

The management of acute primary angle closure is directed at lowering the intraocular pressure and relieving pupil block. Conventional treatment involves the use of medical treatment and laser peripheral iridotomy, respectively, as a means for achieving these aims. Newer therapeutic strategies have been described that are potentially useful adjuncts or alternatives to conventional treatment. Emerging strategies that lower intraocular pressure include anterior chamber paracentesis, as well as laser procedures such as iridoplasty and pupilloplasty. A possible alternative to relieving pupil block is lens extraction, and may be combined with adjunctive measures such as goniosynechiolysis and viscogoniosynechiolysis. Trabeculectomy has a limited role in the acute setting. This review paper reviews the current evidence regarding conventional and newer treatment modalities for acute primary angle closure.

Primary lens extraction for glaucoma management: A review article

Recently, primary lens extraction alone gained more acceptance as an alternative surgical approach for glaucoma management. This view was supported by the advances in phacoemulsification and intraocular lenses with greater safety and visual recovery, in addition to a substantial reduction of intraocular pressure and deepening of the anterior chamber and filtration angle. The decrease in IOP after cataract surgery in primary open-angle glaucoma (POAG) is mild, less predictable, related to baseline levels, and may return to presurgical values after an initial period of reduction. Therefore, the IOP-lowering effect of primary cataract extraction in POAG may be insufficient to achieve adequate IOP control. The IOP reduction after lens extraction is consistently greater in eyes with primary angle closure glaucoma (PACG) than in eyes with POAG. Primary lens extraction in acute PACG eliminates, or at least, reduces the risk of recurrence of acute attacks and deepens the anterior chamber and widens the angle which reduces the risk of progression of peripheral anterior synechiae and development of chronic PACG. Primary lens extraction may be more preferable to glaucoma incisional surgery in mild to moderate PACG eyes with appositional angle closure. The decision to do lens extraction as a primary treatment for glaucoma should be individualized based upon several factors other than the effect on IOP. These factors include patients' characteristics, surgeons' skills and preferences, status of glaucoma control, type of cataract and intraocular lens implanted, and potential harm of laser treatment for late capsular opacification and fibrosis.

Primary phacoemulsification and intraocular lens implantation for acute primary angle-closure

BACKGROUND

To investigate the effect of primary phacoemulsification on intraocular pressure (IOP) in patients with acute primary angle-closure (PAC) and coexisting cataract.

METHODOLOGY

Sixteen eyes of 14 patients with acute PAC received phacoemulsification and intraocular lens implantation as initial management for medically uncontrolled IOP in a retrospective chart review. The effects on IOP, vision, anterior chamber depth (ACD), and number of antiglaucoma medications were evaluated.

PRINCIPAL FINDINGS

The postoperative IOP was reduced in 16 eyes (100%). The mean ± standard deviation preoperative IOP was 48.81 ± 16.83 mm Hg, which decreased postoperatively to 16.46 ± 10.67 mm Hg at 1 day, 9.43 ± 3.03 mm Hg at 1 week, 9.49 ± 2.14 mm Hg at 2 weeks, 10.78 ± 3.56 mm Hg at 1 month, and 10.70 ± 2.80 mm Hg at 3 months (p < 0.001). The mean number of antiglaucoma medications decreased from 3.56 ± 1.14 to 0.13 ± 0.34 (p < 0.001). The average preoperative ACD was 2.08 ± 0.35 mm, which increased to 3.59 ± 0.33 mm after surgery (p < 0.001). Visual acuity (converted into logarithm of the minimum angle of resolution [logMAR]) improved from 1.14 ± 0.71 to 0.73 ± 0.53 (p =  0.001).

CONCLUSIONS

Primary phacoemulsification plus intraocular lens implantation lowered IOP, reduced the use of antiglaucoma medications, and improved vision in patients with acute PAC. This is a safe and effective method of IOP control and can be considered a first treatment option in managing patients with acute PAC and coexisting cataract.

Angle-closure glaucoma: the role of the lens in the pathogenesis, prevention, and treatment

Primary angle-closure glaucoma is a major cause of blindness worldwide. It is a disease of ocular anatomy that is related to pupillary-block and angle-crowding mechanisms of filtration angle closure. Eyes at increased risk for primary angle-closure are small with decreased axial length, anterior chamber depth, and filtration angle width, associated with a proportionately large lens. Angle-closure glaucoma afflicts Asian and Eskimo eyes more frequently than eyes in other races with similar predisposing dimensions. The treatment of primary angle closure addresses its causal mechanisms. Laser peripheral iridotomy equalizes the anterior and posterior pressures and widens the filtration angle by reducing the effect of pupillary block. Argon laser peripheral iridoplasty contracts the iris stroma to reduce angle crowding and is helpful for some affected eyes. Lensectomy dramatically widens the angle and eliminates pupillary block. Clinical reports of lensectomy with posterior chamber intraocular lens implantation in the treatment of acute, chronic, and secondary angle-closure glaucoma describe very favorable results. The appropriate role for lensectomy in the management of primary angle closure, however, remains unproven. Prospective, randomized clinical trials are ongoing to determine the value and comparative risks and efficacy of lensectomy versus medical therapy, laser peripheral iridotomy, laser iridoplasty, and filtration procedures for the treatment of acute and chronic primary angle closure and for the prevention of chronic angle-closure glaucoma, both after and in place of laser peripheral iridotomy.

Primary phacoemulsification and aspiration combined with 25-gauge single-port vitrectomy for management of acute angle closure

PURPOSE

To describe a technique using phacoemulsification and aspiration (PEA) combined with 25-gauge single-port vitrectomy as a primary treatment for acute angle closure (AAC).

METHODS

Seventeen consecutive cases of AAC were treated with 1) transconjunctival limited single-port vitrectomy with a 25-gauge vitrector and 2) transcorneal PEA and cortex removal followed by implantation of foldable intraocular lenses (IOL).

RESULTS

Intraocular pressure (IOP) control was achieved in all 17 eyes examined. Mean preoperative IOP was 51.8+/-13.1 mmHg, and mean IOP on postoperative day 1 was 18.3+/-8.5 mmHg. Additional anti-glaucoma surgery was necessary in one eye. IOL could not be implanted because of zonular dialysis in one eye. Postoperative complications were seen in three cases (one retinal hemorrhage and two papilledema).

CONCLUSIONS

The PEA procedure is efficient as a primary treatment of AAC. Single-port vitrectomy with a 25-gauge vitrector facilitated PEA and IOL implantation.