Immediate argon laser peripheral iridoplasty (ALPI) as initial treatment for acute phacomorphic angle-closure (phacomorphic glaucoma) before cataract extraction: a preliminary study

Efficacy and Safety of Argon Laser Peripheral Iridoplasty and Systemic Medical Therapy in Asian Patients with Acute Primary Angle Closure: A Meta-Analysis of Randomized Controlled Trials

PURPOSE

The purpose of this meta-analysis was to assess the percent reduction in the intraocular pressure (IOP) after argon laser peripheral iridoplasty (ALPI) and systemic medical therapy in patients with acute primary angle closure (APAC).

METHODS

We searched a number of electronic databases, including MEDLINE, EMBASE, PubMed, and Cochrane Library. We searched the electronic databases from the inception of the databases to August 2018. The primary outcomes included the IOP reduction (IOPR), percent reduction in IOP (IOPR%) from baseline to the endpoint and peripheral anterior synechiae (PAS). The secondary outcomes included the cup-to-disc ratio (CDR), mean endothelial count, and percent of patients requiring topical glaucoma medication. Summary weighted mean difference (WMD), odds ratio (OR), and 95% confidence intervals (CIs) were calculated.

RESULTS

Four eligible studies including 183 eyes (92 in the ALPI group and 91 in the medical therapy group) were identified. When comparing ALPI to medical therapy, the WMDs of the IOPR% were 30.03 (95% CI: 21.33 to 38.72, p < 0.00001) at 15 minutes, 27.39 (95% CI: 18.89 to 35.89, p < 0.00001) at 30 minutes, 18.15 (95% CI: 10.63 to 25.68, p < 0.00001) at 1 hour, and 12.91 (95% CI: 4.50 to 21.32, p=0.003) at 2 hours. There was no statistically significant difference between the two groups at 24 hours and at more than 6 months after therapy. Meanwhile, no significant difference was observed in the degree of PAS, CDR, mean endothelial count, and percent of patients requiring topical glaucoma medication after treatment between the two groups.

CONCLUSIONS

Both ALPI and systemic medications were effective with regard to decreasing the IOP. ALPI was more effective in lowering the IOP within the first two hours. Therefore, ALPI may be a better choice for rapidly lowering the IOP in patients with APAC within a short period.

Quantitative assessment of changes in anterior segment morphology after argon laser peripheral iridoplasty: findings from the EARL study group

IMPORTANCE

Argon laser peripheral iridoplasty (ALPI) could be effective in widening residual angle closure following laser peripheral iridotomy (LPI).

BACKGROUND

We investigated changes in angle parameters following ALPI and its safety profile in this study.

DESIGN

Retrospective, observational case series.

PARTICIPANTS

The records from a single centre, of 36 patients (60 eyes) who underwent ALPI, for residual angle closure following LPI, were reviewed.

METHODS

We analysed anterior chamber parameters in anterior segment optical coherence tomography (ASOCT) images using customized software pre- and post-ALPI. Paired t-test was used to compare changes.

MAIN OUTCOME MEASURES

ASOCT parameters analysed included angle opening distance (AOD 500 and 750), trabecular iris surface area (TISA 500 and 750), anterior chamber width (ACW), anterior chamber volume (ACV), angle recess area (ARA), anterior chamber area (ACA), anterior chamber depth (ACD) and lens vault (LV).

RESULTS

There was a mean increase in AOD 500 (0.05 vs. 0.16 mm, P < 0.001), AOD 750 (0.15 vs. 0.27 mm, P < 0.001), TISA 500 (0.010 vs. 0.038 mm² , P < 0.001), TISA 750 (0.039 vs. 0.102 mm² , P < 0.001), ACV (89.76 vs. 102.25 mm³ , P = 0.01), ARA 500 (0.015 vs. 0.033 mm² , P < 0.001) and ARA 750 (0.044 vs. 0.088 mm² , P < 0.001). There was no significant change in ACW, ACD, ACA and LV. Mean intraocular pressure (IOP) decreased post-ALPI (17.2 vs. 15.7 mmHg, P = 0.002). The mean follow-up duration was 2.1 years (range 0.5-5 years).

CONCLUSIONS AND RELEVANCE

ALPI results in changes to the angle morphology and lowered IOP in eyes with residual angle closure. Our findings suggest a possible role for ALPI in eyes with residual angle closure following peripheral iridotomy.

Functional results of cataract surgery in the treatment of phacomorphic glaucoma

Purpose. Analysis of functional outcome and complications reported in patients diagnosed with phacomorphic glaucoma, in which phacoemulsification or extracapsular extraction of the lens was performed. Methods. The retrospective study included 38 eyes diagnosed with phacomorphic glaucoma. In 25 cases, group 1, the lens was removed by phacoemulsification and in 13 cases, group 2, by extracapsular extraction. Intraocular pressure, visual acuity, and anterior chamber depth were evaluated preoperative and postoperative. The incidence of intra and postoperative complications was analyzed. The minimum follow-up period was 12 months. Results. The mean IOP decreased from the preoperative value of 38.4 +/ - 11.3 mmHg to 13.5 +/ - 3.4 mmHg in group 1 and 11.5 +/ - 3.2 mmHg in group 2. Persistent corneal edema was observed in 32% patients from group 1 and 23% of the patients from group 2. The inflammatory reaction of anterior chamber prevailed in patients from group 2 (46.1%). ACD modified from the preoperative mean of 1.3 +/- 0.5 mm to 2.3 +/- 0.2 mm in both groups. At the end of follow-up in both groups, the average BCVA was 0.6. 18.42% of the cases required long-term topical hypotensive therapy. Conclusions. Both phacoemulsification and extracapsular extraction were safe and effective procedures in the treatment of phacomorphic glaucoma, ensuring a rapid functional recovery and a satisfactory long-term IOP control. Although the rate of immediate postoperative complications and the final functional outcome were better in patients treated with phacoemulsification, not all the cases could be subjected to this type of surgery.

Current and Future of Laser Therapy in the Management of Glaucoma

There has been tremendous progress in the past decades in the utilization of lasers for treating patients with glaucoma. This article reviews the use of lasers in different areas of glaucoma, including the shift from argon laser trabeculoplasty (ALT) to selective laser trabeculoplasty (SLT), laser trabeculoplasty as an initial treatment for glaucoma, new laser trabeculoplasty procedures under investigation, and other recent laser treatment modalities such as endoscopic cyclophotocoagulation and laser-assisted deep sclerectomy.

Management of Primary Angle-Closure Glaucoma

Primary angle-closure glaucoma (PACG) is a progressive optic nerve degeneration and is defined as a glaucomatous optic neuropathy with associated characteristic enlargement of optic disc cupping and visual field loss that is secondary to ocular hypertension caused by closure of the drainage angle. Angle closure is caused by appositional approximation or adhesion between the iris and the trabecular meshwork. The main treatment strategy for PACG lies in the reduction of intraocular pressure, reopening of the closed angle, and possible prevention of further angle closure. There is no universally agreed best surgical treatment for PACG. Trabeculectomy, goniosynechialysis (GSL), glaucoma implant, and cyclodestructive procedures are effective surgical options. Each of them plays an important role in the management of PACG with its own pros and cons. Accumulating evidence is available to show the effectiveness of visually significant and visually nonsignificant cataract extraction in the treatment of PACG. Trabeculectomy and GSL are often combined with cataract extraction, which may offer additional pressure control benefits to patients with PACG. This review article will discuss laser peripheral iridotomy, argon laser peripheral iridoplasty, and surgeries such as GSL, phacoemulsification, and phaco plus glaucoma surgeries that lower intraocular pressure and also alter the anterior segment and/or drainage angle anatomy. Currently, glaucoma implants and cyclodestruction are mainly reserved for PACG patients who have failed previous filtering operations. Their role as initial surgical treatment for PACG will not be discussed.

Evaluation of the efficacy of laser peripheral iridoplasty in reversing the darkroom provocative test result in Chinese patients with primary angle closure status post laser iridotomy

AIM

To investigate the efficacy and safety of krypton laser peripheral iridoplasty (LPIP) for Chinese patients with primary angle closure (PAC) or primary angle-closure glaucoma (PACG) status post laser iridotomy in reversing the positive results of the dark room provocative test (DRPT).

METHODS

This study was prospective, noncomparative, interventional case series. Thirty-three patients (thirty-eight eyes) with PAC or PACG status post patent laser iridotomy and maintained normal intraocular pressure (IOP) but with positive DRPT results were enrolled. All the subjects were treated with krypton LPIP. DRPT was repeated after krypton LPIP. Results of DRPT were recorded. The visual acuity, IOP and gonioscopy were analyzed before and after krypton LPIP. A minimum time limit for follow-up was 6mo.

RESULTS

Thirty-three patients (thirty-eight eyes) were followed for 17.7±8.37mo (range 7-41mo) after LPIP. Positive results of DRPT decreased from 38 eyes to 9 eyes (23.7%) after LPIP. Peripheral anterior synechiae of angle in 34 of 38 eyes (89.5%) remained unchanged at dynamic gonioscopy throughout the follow-up period after LPIP.

CONCLUSION

LPIP decreased positive rates of the DRPT significantly. The mechanism may be that LPIP minimized contact between the peripheral iris and trabecular meshwork, which is a key factor for developing peripheral anterior synechiae.

Cross-sectional study of the retinal nerve fiber layer thickness at 7 years after an acute episode of unilateral primary acute angle closure

The purpose of this article is to investigate the long-term retinal nerve fiber layer (RNFL) status and determinants of RNFL thinning after an episode of unilateral primary acute angle closure (AAC). This cross-sectional study analyzed the medical records of consecutive patients with a single episode of unilateral AAC from 1999 to 2009 in Hong Kong. The peripapillary RNFL thickness was correlated with age, gender, presenting intraocular pressure (IOP), time to laser iridotomy, time to cataract extraction, follow-up duration, as well as the last IOP, vertical cup-to-disc ratio (CDR), and vision. The fellow uninvolved eye was used as a proxy comparison of RNFL loss in the attack eye. In 40 eligible patients, the mean age was 68.3 ± 8.7 years with a male-to-female ratio of 1:7. The mean presenting IOP was 49.2 ± 14.0 mm Hg and the time from presentation to laser iridotomy was 6.7 ± 6.9 days. Forty percent of subjects received a cataract extraction at 3.2 ± 2.9 years after the attack. The last IOP, CDR, and LogMAR vision were 16.0 ± 3.8 mm Hg, 0.6 ± 0.2, and 0.6 ± 0.6 LogMAR units, respectively, at 7.9 ± 2.4 years. The RNFL thickness in the attack eye (69.2 ± 19.1 μm) was 25.2 ± 17.9% thinner than the fellow eye (93.0 ± 17.8 μm) at 7.5 ± 2.9 years post-AAC. Using univariate analysis, the last vertical CDR (odds ratio [OR] = 17.2, P = 0.049) and LogMAR visual acuity (VA) (OR = 6.6, P = 0.03) were the only significant predictors for RNFL thinning whereas none of the other covariates showed significant associations (P > 0.1). At 7.5 years following unilateral AAC, the RNFL thickness was 25% thinner than the fellow eye. CDR enlargement and poor VA were the only significant predictors for RNFL loss.

Role of Laser Iridoplasty in the Management of Angle Closure Mechanisms other than Pupillary Block

PURPOSE

To investigate the treatment outcomes of argon laser peripheral iridoplasty (ALPI) in angle closure mechanisms other than pupillary block.

METHODS

We conducted a comprehensive chart review to evaluate consecutive patients who underwent ALPI due to unsuccessful laser iridotomy (whenever the angles remained occludable) between July 2009 and April-2012. An occludable angle was defined as the posterior trabecular meshwork not visible for ≤180° without indentation on dark room gonioscopy. Eyes with previous incisional surgery or more than 90° of peripheral anterior synechiae were excluded. Main data collected were age, presence of glaucoma, pre- and postlaser intraocular pressure (IOP), angle-status, and underlying angle closure mechanism. Main outcomes were post ALPI angle widening on gonioscopy and magnitude of IOP reduction.

RESULTS

A total of 41 eyes (27 patients) with persistent occlu-dable angles were initially included in the analysis, comprising approximately 14% of the 196 patients (321 eyes) that had under gone laser iridotomy during the predefined period. Among these cases, most common angle closure mechanisms were plateauiris (56%) and lens-induced component (34%). Patients with plateau iris were mostly women and younger than those with lens-induced component (p ≤ 0.03). A total of 35 eyes (23 patients) underwent ALPI (63% had glaucoma). Mean IOP was significantly reduced from 18. 2 ± 4.7 to 14.6 ± 3.8 (p < 0.01), with no significant difference between patients with plateau iris and lens-induced components (p = 0.22). Over 91% of these eyes showed nonoccludable angles following ALPI (follow-up of 11.8 ± 3.3 months).

CONCLUSION

In this series of middle-aged patients with occlu-dable angles, despite a patent iridotomy, ALPI was a useful procedure independent of the underlying mechanism, leading to angle widening and moderate IOP reduction in most cases. How to cite this article: Prado VG, Dorairaj S, Biteli LG, Sousa AKS, Moreno PAM, Lopes FS, Prata TS. Role of Laser Iridoplasty in the Management of Angle Closure Mechanisms other than Pupillary Block. J Curr Glaucoma Pract 2014;8(2):82-84.

Manual Small Incision Cataract Surgery in Phacomorphic Glaucoma: Surgical Technique and Outcome in North-eastern India

Background: North-eastern region of India continue to suffer from limited resources, added upon by Mongoloid racial similarity and poor cataract surgery rate has contributed to the increase incidence of advanced cataract like phacomorphic glaucoma.

Objective: To evaluate the visual prognosis and related complications of phacomorphic glaucoma cases by manual small incision cataract surgeries in North-eastern region of India.

Materials and methods: This retrospective case series study includes 65 phacomorphic glaucoma cases diagnosed between June 2009 to December 2011 in Jawaharlal Nehru Institute of Medical Sciences, Manipur. Preoperative routine evaluation includes slit-lamp biomicroscopy, measurement of IOP, gonioscopy of fellow eye, axial length measurement, AC depth and lens thickness by A-scan. Manual small incision cataract surgery with intraocular lens implantation was performed in all the 65 eyes. Complete ophthalmic examination was done at each follow-up visit.

Results: The mean preoperative IOP was 35.14 (±6.35) mm Hg and IOP at the 3rd month follow-up was 18.65 (±1.3) mm Hg with a statistically significant lowering of IOP (p < 0.0001) at the last follow-up. Intraoperative complications were minimal. Corneal edema, fibrinous exudates in AC was seen in few cases. Postoperative best corrected visual acuity was 6/6-6/12 in 46 eyes, 6/18-6/36 in 12 eyes, 6/60-3/60 in 4 eyes and less than 3/60 in three eyes. Antiglaucoma medication was discontinued immediately after each surgery.

Conclusion: Manual small incision cataract surgery being inexpensive play a key role in management of poor outreach program marker like phacomorphic glaucoma in effectively controlling the IOP and achieving good visual acuity with minimal complications.

How to cite this article: Rajkumari V, Kaminibabu KS, Bhabanisana RD, Victor R. Manual Small Incision Cataract Surgery in Phacomorphic Glaucoma: Surgical Technique and Outcome in North-eastern India. J Current Glau Prac 2013; 7(2):43-48.

Prospective case series on trabecular-iris angle status after an acute episode of phacomorphic angle closure

AIM

To investigate the trabecular-iris angle with ultrasound biomicroscopy (UBM) post cataract extraction after an acute attack of phacomorphic angle closure.

METHODS

This prospective study involved 10 cases of phacomorphic angle closure that underwent cataract extraction and intraocular lens insertion after intraocular pressure (IOP) lowering. Apart from visual acuity and IOP, the trabecular-iris angle was measured by gonioscopy and UBM at 3 months post attack.

RESULTS

In 10 consecutive cases of acute phacomorphic angle closure from December 2009 to December 2010, gonioscopic findings showed peripheral anterior synechiae (PAS) ≤ 90° in 30% of phacomorphic patients and a mean Shaffer grading of (3.1±1.0). UBM showed a mean angle of (37.1°±4.5°) in the phacomorphic eye with the temporal quadrant being the most opened and (37.1°±8.0°) in the contralateral uninvolved eye. The mean time from consultation to cataract extraction was (1.4±0.7) days and the mean total duration of phacomorphic angle closure was (3.6±2.8) days but there was no correlation to the degree of angle closure on UBM (Spearman correlation P=0.7). The presenting mean IOP was (50.5±7.4) mmHg and the mean IOP at 3 months was (10.5±3.4) mmHg but there were no correlations with the degree of angle closure (Spearman correlations P=0.9).

CONCLUSION

An open trabecular-iris angle and normal IOP can be achieved after an acute attack of phacomorphic angle closure if cataract extraction is performed within 1 day - 2 days after IOP control. Gonioscopic findings were in agreement with UBM, which provided a more specific and object angle measurement. The superior angle is relatively more narrowed compared to the other quadrants. All contralateral eyes in this series had open angles.

Prospective study on retinal nerve fibre layer changes after an acute episode of phacomorphic angle closure

To investigate the retinal nerve fibre layer (RNFL) changes after an acute attack of phacomorphic angle closure. This prospective study involved ten cases of phacomorphic angle closure that underwent cataract extraction and intraocular lens insertion after intraocular pressure lowering. Apart from visual acuity and intraocular pressure (IOP), RNFL thickness and vertical cup disc ratio (VCDR) were measured by optical coherence tomography (OCT) at 3–9 months post attack. Humphrey visual field assessment was performed at 9 months post attack. All cases had mean phacomorphic duration of <5 days. Postoperatively, best correct Snellen visual acuity was 0.4 ± 0.2 and IOP at 9 months was 11.0 ± 3.1 mmHg. There was no difference in VCDR and RNFL between the attack and contralateral eye at 3 months post attack (both p = 0.4). At 9 months post attack, there was significant thinning in the average (p = 0.01), superior (p = 0.01), and inferior (p = 0.006) RNFL. There was no significant difference in the pattern standard deviation (PSD) between the two eyes on the Humphrey visual field nor was there any correlation between PSD severity and RNFL thinning (all p > 0.2. Patients with <5 days duration of phacomorphic angle closure are likely to have reasonable postoperative vision. An acute episode of phacomorphic angle closure can trigger an accelerated RNFL thinning despite normal IOP and open angles, most noticeable in the superior and inferior quadrants, occurring between 3 and 9 months post attack. Glaucomatous optic neuropathy in the attack eye was evident by OCT but not by visual field assessment at the same time interval.

Bilateral phacomorphic angle-closure glaucoma in a highly myopic patient secondary to isolated spherophakia

BACKGROUND

Angle closure most commonly occurs in older hyperopic patients as a result of primary relative pupil block. Less frequently, angle closure occurs in highly myopic patients with conditions other than primary relative pupil block. This report presents the diagnosis, pathophysiologic mechanism, and management of a patient with both high myopia and bilateral advanced phacomorphic angle-closure glaucoma caused by isolated spherophakia.

CASE

A 40-year-old asymptomatic man with very high myopic astigmatism presented with chronic angle closure and an intraocular pressure of 42 mmHg in both eyes. Additionally there was a nonmyopic fundus and 24-mm axial length, with a clear crystalline lens protruding through the pupillary plane in each eye, confirmed by B-scan ultrasonography. Gonioscopy and A-scan and B-scan ultrasonography identified the pathogenesis of intraocular pressure elevation, angle closure, and high myopia to be lenticular in origin. Initial medical therapy and subsequent laser iridotomy relieved the pupil block angle closure and successfully lowered intraocular pressure.

CONCLUSION

Angle closure can occur in highly myopic eyes. Careful gonioscopy and ultrasonography can lead to the correct diagnosis and tailored management for these eyes. Phacomorphic angle-closure glaucoma from spherophakia is associated with Weill-Marchesani syndrome as well as a few other uncommon syndromes. Isolated pseudophakia is a rarely reported cause of phacomorphic angle closure.

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.

Argon Laser Peripheral Iridoplasty (ALPI): An Update

Argon laser peripheral iridoplasty is a useful procedure to eliminate appositional angle closure resulting from mechanisms other than pupillary block. For those eyes with angle closure originating at an anatomic level posterior to the iris, such as plateau iris, lens-induced angle closure, or posterior segment processes (malignant glaucoma, central retinal vein occlusion, etc.), laser iridotomy by itself may be insufficient to treat the underlying disease mechanism. Argon laser peripheral iridoplasty is often useful in these cases to further open the angle. It can be used to break an acute attack of angle-closure glaucoma and relieve appositional angle closure secondary to plateau iris syndrome, or lens-related angle closure, and to widen the angle prior to argon laser trabeculoplasty. Peripheral location of long-duration, low-power, large spot size laser burns is essential for optimal success.

Phacomorphic glaucoma: case and review

Phacomorphic glaucoma is a lens-induced secondary angle closure glaucoma that may occur as a result of mature cataract formation. A patient with markedly asymmetric cataract and anterior chamber depth was referred after the development of significant eye pain and elevated intraocular pressure that did not respond to topical antiglaucoma medications. The presence of an asymmetric mature lens, angle closure, and intraocular pressure elevation in the affected eye led to the diagnosis of phacomorphic glaucoma. Because the patient was systemically ill, physically frail, and had poor vision in the affected eye since birth, secondary to strabismic amblyopia, initial therapy was medically directed toward pain management. Cycloplegia, corticosteroids, and aqueous suppressants successfully ameliorated the patient's intraocular pressure and adequately controlled pain. However, progression to phacolysis and subsequent failure of pain management necessitated referral for lens extraction. The diagnosis and mechanism of phacomorphic glaucoma is discussed along with a review of current treatment modalities.