Recurrent acute angle-closure attack due to plateau iris syndrome after cataract extraction with or without argon laser peripheral iridoplasty: a case report.

BACKGROUND: We describe two cases of recurrent acute angle-closure attack in patients with plateau iris syndrome after cataract extraction. Argon laser peripheral iridoplasty and cataract extraction have been used to reduce the occurrence of acute angle-closure attack in plateau iris syndrome although the risk cannot be completely eliminated. There is no consensus on the long term management of plateau iris syndrome. This is, as far as we know, the first case report of recurrent acute angle-closure attack in plateau iris syndrome after cataract extraction. CASE PRESENTATION: We report two cases of recurrent acute angle-closure attack in 2 Chinese patients with plateau iris syndrome. The first patient was a 69 year-old woman who received bilateral argon laser peripheral iridoplasty and cataract extraction 2 years prior to the latest acute angle-closure with right eye intraocular pressure 48 mmHg. The attack was aborted medically. Peripheral iridotomy was patent and argon laser peripheral iridoplasty marks were mostly at peripheral 2/3 of the iris. Anterior segment optical coherence tomography confirmed bilateral plateau iris configuration. Use of long term pilocarpine or repeated argon laser peripheral iridoplasty to prevent recurrent angle-closure attack was discussed but she opted for observation. The second patient was a 64 year-old man presented with acute angle-closure after cataract extraction despite placement of laser peripheral iridotomy. Plateau iris syndrome was confirmed by anterior segment optical coherence tomography and he received argon laser peripheral iridoplasty. CONCLUSIONS: Acute angle-closure due to plateau iris syndrome can still occur despite previous cataract extraction and argon laser peripheral iridoplasty. These are the first reported cases of recurrent acute angle-closure attack due to plateau iris syndrome following cataract extraction, with or without previous argon laser peripheral iridoplasty. Repeated treatment with argon laser peripheral iridoplasty or pilocarpine could be considered although the long term efficacy is questionable. Argon laser peripheral iridoplasty should be applied as peripheral as possible so as to open up the drainage angle effectively.

Argon laser peripheral iridoplasty for chronic primary angle-closure and angle-closure glaucoma in caucasians.

PURPOSE: To investigate whether the peripheral thinning and shrinking of the iris as induced with Argon laser peripheral iridoplasty (ALPI) has an effect on intraocular pressure (IOP), angle structure and 3-D anterior segment (AS) morphology in Caucasians with chronic primary angle-closure (PAC) and primary angle-closure glaucoma (PACG). METHODS: Twenty-four eyes of 24 patients (age 67.7 ± 8.9 years; seven males; 17 females) diagnosed with PAC (n = 10) or PACG (n = 14) were assigned for ALPI prior to laser peripheral iridotomy (LPI) and consecutively enrolled in this prospective interventional study. Intraocular pressure (IOP) was measured with Goldmann applanation tonometry, angle structure with gonioscopy using the Shaffer grading system and AS morphology with the Pentacam rotating Scheimpflug camera prior to and 3 months after ALPI. Intraocular pressure (IOP)-lowering medication was not changed during follow-up. RESULTS: Intraocular pressure (IOP) changed statistically significantly from 18.8 ± 3.6 to 14.7 ± 3.1 mmHg (p < 0.001). Gonioscopy showed a statistically significant angle widening in all four quadrants: nasally from Shaffer 1.04 ± 0.98 to 2.54 ± 1.1 (p < 0.001), superiorly from 0.39 ± 0.66 to 1.58 ± 1.21 (p < 0.001), temporally from 0.87 ± 1.01 to 2.17 ± 1.24 (p = 0.001) and inferiorly from 1.22 ± 0.74 to 2.75 ± 0.9 (p < 0.001). Pentacam parameters like anterior chamber depth, volume and angle did not increase statistically significantly. CONCLUSION: Argon laser peripheral iridoplasty (ALPI) is a safe and effective procedure for reducing appositional angle-closure and thus IOP in nonacute PAC and PACG patients.

Argon laser peripheral iridoplasty versus systemic intraocular pressure-lowering medications as immediate management for acute phacomorphic angle closure.

BACKGROUND: The purpose of this study was to compare the efficacy and safety of argon laser peripheral iridoplasty (ALPI) and systemic intraocular pressure (IOP)-lowering medications in the immediate management of acute phacomorphic angle closure. METHODS: Consecutive cases of acute phacomorphic angle closure were randomized to receive ALPI and an intravenous or oral carbonic anhydrase inhibitor as initial treatment. Intravenous mannitol was administered for presenting IOP > 60 mmHg or IOP > 40 mmHg 2 hours posttreatment in both arms. RESULTS: Of 10 consecutive cases, six received medical therapy and four received ALPI. Fifty percent in the medical group and none in the ALPI group required intravenous mannitol. The ALPI group took less time to achieve IOP < 25 mmHg (18.8 ± 7.5 minutes versus 115.0 ± 97.0 minutes, P = 0.001, F test); had a greater IOP reduction within 30 minutes (69.8% ± 7.7% versus 40.9 ± 23.9%, P = 0.03, t-test); and had a consistently smaller post-attack cup to disc ratio (0.50 ± 0.02 versus 0.60 ± 0.20, P = 0.002, F test). CONCLUSION: ALPI offers greater safety, consistency, and efficacy than systemic IOP-lowering medications as initial treatment for phacomorphic angle closure.

Peripheral laser iridoplasty opens angle in plateau iris by thinning the cross-sectional tissues.

Plateau iris syndrome has been described as persistent angle narrowing or occlusion with intraocular pressure elevation after peripheral iridotomy due to the abnormal plateau iris configuration. Argon laser peripheral iridoplasty (ALPI) is an effective adjunct procedure to treat plateau iris syndrome. Classic theory suggests that the laser causes the contraction of the far peripheral iris stroma, "pulls" the iris away from the angle, and relieves the iris-angle apposition. We report a case of plateau iris syndrome that was successfully treated with ALPI. Spectral domain optical coherence tomography confirmed the angle was open at areas with laser treatment but remained appositionally closed at untreated areas. Further analysis suggested significant cross-sectional thinning of the iris at laser-treated areas in comparison with untreated areas. The findings indicate that APLI opens the angle, not only by contracting the iris stroma, but also by thinning the iris tissue at the crowded angle. This is consistent with the ALPI technique to aim at the iris as far peripheral as possible. This case also suggests that spectral domain optical coherence tomography is a useful adjunct imaging tool to gonioscopy in assessing the angle condition.