Peripheral iridotomy for pigmentary glaucoma.

Laser peripheral iridotomy has recently been suggested as a treatment, and perhaps a cure, for pigment dispersion syndrome and pigmentary glaucoma. 1 I report herein a case in which a peripheral iridotomy had no apparent effect on iris configuration or intraocular pressure (IOP). Report of a Case. A 38-year-old white woman presented with a history of bilateral pigment dispersion and elevated IOP despite treatment with 0.5% levobunolol hydrochloride twice daily in both eyes. Visual acuity was 20/20 OU. The refraction was -2.50 +1.50 X4 ODand -2.50 +1.25 X2OS. Slit-lamp examination was remarkable for Krukenberg spindles in both eyes (right eye greater than left eye), and multiple midperipheral radial iris transillumination defects (right eye greater than left eye). Intraocular pressure was 27 mm Hg in the right eye and 28 mm Hg in the left. Gonioscopy revealed homogeneous dense pigmentation of the trabecular meshwork and posterior bowing of the peripheral iris

ABSTRACTAimTo compare intraocular pressure and anterior chamber angle changes between pilocarpine and laser peripheral iridotomy in primary angle closure.Materials and methodsIn this clinical trial study, 34 eyes of 29 patients with primary angle-closure were prospectively enrolled between November 2015 and February 2016. Intraocular pressure and anterior segment optical coherence tomography were performed at three separate times: on the initial conditions, 3–5 days of administration of topical pilocarpine 2%, and 1 week after laser iridotomy. Anterior chamber angle parameters were the angle opening distance (AOD) and trabecular–iris space area (TISA).ResultsThe intraocular pressure reduction following pilocarpine administration was significant compared to laser iridotomy: 3.9 mm Hg (−32.5 to 0.20) vs 1.8 mm Hg (−33.5 to 2.30) (p = 0.002). Meanwhile, the increment of angle parameters following laser iridotomy was significant compared to pilocarpine. The AOD750 increment of both nasal and temporal quadrant following laser iridotomy was significant compared to pilocarpine: 0.13 mm (−0.27 to 0.28) vs 0.05 mm (−0.35 to 0.29) (p = 0.003) and 0.12 mm (−0.10 to 0.34) vs 0.04 mm (−0.27 to 0.19) (p = 0.002), respectively. The TISA750 increment of both nasal and temporal quadrant following laser iridotomy was also significant compared to pilocarpine: 0.05 mm2 (−0.06 to 0.20) vs 0.02 mm2 (−0.12 to 0.13) (p = 0.023) and 0.04 mm2 (−0.04 to 0.17) vs 0.01 mm2 (−0.14 to 0.18) (p = 0.012), respectively.ConclusionLaser peripheral iridotomy widens the angle greater than topical pilocarpine, but topical pilocarpine lowers the intraocular pressure greater than laser iridotomy. These data suggest that pilocarpine has another mechanism to decrease the intraocular pressure in primary angle-closure, besides widening the angle.How to cite this articleYunard A, Oktariana VD, et al. Comparison of Intraocular Pressure and Anterior Chamber Angle Changes between Pilocarpine and Laser Peripheral Iridotomy. J Curr Glaucoma Pract 2019;13(1):32–36.

目的 分析激光周边虹膜成形联合激光虹膜根部切除治疗闭角型青光眼的方法及疗效.方法2003年1月～2004年1月间应用氩激光周边虹膜成形联合Nd:YAG和氩激光周边虹膜切除术21例21眼,缩瞳后氩激光在周边虹膜360°度范围共击射约30点,再于鼻上方或颞上方击射周边虹膜,范围约0.5～1mm,然后用Nd:YAG激光击穿虹膜.结果术前术后平均视力无明显变化,术后1周眼压7～20mmHg,平均眼压14mmHg,暗室试验全部阴性.所有患者均可见周边切除孔沟通前后房,前房角均有不同程度加宽.结论激光周边虹膜成形联合虹膜根部切除既可解除前房阻滞又可加深前房角,是治疗闭角型青光眼的良好方法。

Laser peripheral iridotomy is a useful method in primary angle-closure eyes to prevent angle-closure attack and development of glaucomatous optic nerve damage. The aim of this study was to quantify morphological changes after LPI and their impact on intraocular pressure, and to evaluate predictive parameters for enlarging the anterior chamber angle after laser peripheral iridotomy. Ultrasound biomicroscopy images and intraocular pressure before and after laser peripheral iridotomy from 62 eyes of 34 patients with primary angle-closure were retrospectively analysed. Anterior chamber angle, anterior chamber depth, lens thickness, iris curvature and a newly defined parameter, the end-iris-lens vault were measured. In each quadrant anterior chamber angle was on average significantly larger (at 12 o'clock: from 10.1° to 15.0°; at 3 o'clock: from 13.4° to 19.8°; at 6 o'clock: from 12.2° to 18.5°; at 9 o'clock: from 12.9 to 17.9°; p<0.001) and iris curvature significantly smaller (at 12 o'clock: from 0.26 mm to 0.10 mm; at 3 o'clock: from 0.21 mm to 0.08 mm; at 6 o'clock: from 0.25 mm to 0.08 mm; at 9 o'clock: from 0.21 mm to 0.08 mm; p<0.001) after laser peripheral iridotomy. Anterior chamber depth, lens thickness and end-iris-lens-vault did not significantly change. Anterior chamber angle in each quadrant (p<0.05), and iris curvature at 3 and 6 o'clock positions (p<0.05) were highly predictive for the enlargement of the anterior chamber angle after laser peripheral iridotomy. Intraocular pressure was slightly lower after laser peripheral iridotomy (from 16.6 mmHg to 16.1 mmHg). In primary angle-closure eyes, laser peripheral iridotomy enlarges the angle and flattens the iris significantly. This study demonstrated that a small anterior chamber angle and a large iris curvature are predictive parameters for a greater enlargement of the anterior chamber angle after laser peripheral iridotomy. These new findings underline the importance of the ultrasound biomicroscopy and may help in counselling patients about laser peripheral iridotomy.

This Issue At A Glance

Background Argon laser peripheral iridoplasty (ALPI) is proved to be effective in lowering intraocular pressure (IOP) of patients with mild acute primary angle closure (APAC). It is unclear whether this laser treatment is equally efficient in managing patients with severe APAC. This study aimed to evaluate the IOP-lowering efficacy of ALPI and laser peripheral iridotomy (LPI) on patients with refractory APAC, who have previously responded poorly to intensive medical therapy. Methods Thirty-six patients (8 men and 28 women) were identified as medically refractory APAC, who still had ocular pain, red eye, hazy cornea, closed anterior chamber (AC) angle, and IOP of not less than 21 mmHg after two days or more of anti-glaucoma medication. All enrolled patients underwent ophthalmologic examinations including measurement of visual acuity (VA), best corrected VA (BCVA), IOP, biomicroscopy, and gonioscopy followed by ALPI immediately in the APAC eye and LPI in both eyes. Results All patients were affected unilaterally, with average age of (54.6±11.7) (range, 37.0−75.0) years old. The mean IOP value of the affected eyes dropped from (31.6±7.7) (range, 21.0−39.0) mmHg at enrollment to (18.4±8.7) (range, 10.0−27.0) mmHg 2 hours after ALPI. At follow-up day 7, the mean IOP value maintained at (14.8±4.2) (range, 9.0−21.0) mmHg, which was significantly different (P=0.000) compared with baseline. The average decrease of IOP in the APAC eyes was (16.8±7.4) (range, 12.0−21.0) mmHg. At follow-up three years later, the mean IOP of the APAC eyes stabilized at (16.3±3.2) (range, 9.0−20.0) mmHg with at least 180° of AC angle opened. Conclusion ALPI and LPI lower the IOP of medically refractory cases of APAC though they have responded poorly to anti-glaucoma medication.

Argon laser peripheral iridoplasty (ALPI) could be effective in widening residual angle closure following laser peripheral iridotomy (LPI). We investigated changes in angle parameters following ALPI and its safety profile in this study. Retrospective, observational case series. The records from a single centre, of 36 patients (60 eyes) who underwent ALPI, for residual angle closure following LPI, were reviewed. 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. 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). 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). 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.

The objective was to study the incidence of acute primary angle closure (acute PAC) during pharmacologic mydriasis before cataract surgery and changes in anterior chamber angle parameters in patients with primary angle closure diseases (PACD) with and without prophylaxis laser peripheral iridotomy (LPI). This was a prospective, comparative study of cataract patients with PACD with and without prophylaxis LPI presented at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand during June 2022 to December 2023. The incidence of acute PAC during pharmacologic mydriasis prior to cataract surgery was recorded. Changes in anterior chamber depth (ACD) and anterior chamber angle parameters measured with anterior segment optical coherence tomography before and after cataract surgery were compared between groups using Student t test. There were 195 eyes of 116 patients with a mean age of 70 years enrolled in the study. Eighty patients were women and 36 were men. There were 99 eyes without prophylaxis LPI and 96 eyes with LPI. There was significantly more angle-closure glaucoma in the non-LPI group than in the LPI group. Preoperatively, all anterior chamber angle parameters were significantly greater in the LPI group than in the non-LPI group (P < .001 all parameters), except ACD (P = .83) and anterior chamber width (ACW) (P = .30). All participants underwent uneventful cataract surgery. Postoperatively, all parameters of the anterior chamber angle and ACD increased significantly in both groups. When comparing between groups, all postoperative anterior chamber angle parameters were not significantly different between the groups, but ACD was significantly greater (P = .036) and ACW was lower in the LPI group (P = .008). There was no incidence of acute PAC occurring during pharmacological mydriasis before cataract surgery in both groups. There was no incidence of acute PAC in patients with and without prophylaxis LPI during pharmacological mydriasis in the preoperative preparation for cataract surgery. Eyes without LPI showed significantly lower preoperative anterior chamber angle parameters compared to eyes with previous LPI, but not significantly different postoperatively. The benefits of prophylactic LPI for PACD scheduled for cataract surgery must be further investigated.

To compare the change in endothelial cell counts (ECC) after early phacoemulsification and laser peripheral iridotomy (LPI) using sequential argon:yttrium-aluminum-garnet (YAG) laser technique for the treatment of acute primary angle closure (APAC). This was a retrospective chart review, case-control study; 86 APAC patients were enrolled. Sixteen patients who underwent early phacoemulsification with intraocular lens implantation and 32 patients who underwent LPI were matched by propensity score analysis. All subjects underwent a complete ophthalmic examination, including intraocular pressure (IOP) measurements, optic disc examinations, and gonioscopy. ECC were acquired at the center of the cornea with a noncontact specular microscope before treatment, and at 1, 6, 12, and 24months following phacoemulsification or LPI. The mean follow-up was 26.1 ± 4.7months in the phacoemulsification group and 26.3 ± 4.5months in the LPI group. After intervention, the changes in anterior chamber depth and Shaffer grading by gonioscopy were significantly different between groups. ECC were not different before treatment; however, after phacoemulsification or LPI at 12months (2280 ± 320 vs 1993 ± 380cells/mm(2)) and 24months (2113 ± 333 vs 1880 ± 422cells/mm(2)), there was a significant difference between the two groups (P = 0.040 and P = 0.032 respectively). Regression analysis showed that anterior chamber depth at baseline (P = 0.041) and intervention modality (phacoemulsification vs LPI; P < 0.001) were significantly related to the change in ECC. Early phacoemulsification showed lower endothelial cell loss than did LPI in the treatment of APAC after a 2-year follow-up. In terms of ECC, early phacoemulsification could be a better intervention modality for APAC.

Anterior chamber depth and intraocular pressure following panretinal argon laser photocoagulation for diabetic retinopathy

To examine prospectively the effects of small-incision phacoemulsification and intraocular lens implantation (PEA+IOL) on anterior chamber depth (ACD) and intraocular pressure (IOP) using a newly developed scanning peripheral ACD analyzer (SPAC). Twenty-eight eyes of 21 patients who underwent PEA+IOL without any complications were examined and divided into 7 eyes each of grades 1 to 4 according to the Van Herick technique. The SPAC measured ACD consecutively from the vicinity of the pupil center to the periphery at 0.4-mm intervals. Changes in ACD and IOP as a result of PEA+IOL were investigated, and the factors contributing to the changes in ACD and IOP were examined. PEA+IOL increased ACD significantly at all groups. The average changing rates were 3.19 +/- 0.67 times (Van Herick grade 1), 2.00 +/- 0.80 times (Van Herick grade 2), 1.92 +/- 0.32 times (Van Herick grade 3), and 1.36 +/- 0.65 times (Van Herick grade 4), respectively. The closer to the pupil center the measurement point was, the larger was the increase in ACD. However, the rates of increase in ACD were similar among the measurement points. The increases in ACD were significantly large in patients having a shallow preoperative ACD and a small optic axis length. The IOP reduction became significantly large in eyes with a shallow preoperative ACD. The SPAC enabled quantitative measurement of changes in ACD from the vicinity of the pupil center to the periphery as a result of PEA+IOL. Changes in ACD resulting from PEA+IOL were thought to exert a greater effect on aqueous humor outflow facility as the postoperative ACD became shallower.

This Issue at a Glance

To evaluate the changes in the anterior segment parameters of the subjects with primary angle closure suspect (PACS) before and after laser iridotomy (LI) using the Pentacam and gonioscopy. Forty-eight eyes of 48 PACS were included. Anterior chamber angle (ACA), central anterior chamber depth (ACD), anterior chamber volume (ACV) and central corneal thickness (CCT) were recorded from the Pentacam before and one month after LI. ACA was graded according to Shaffer classification using the Goldmann gonioscopy. ACA increased significantly from 25.59±4.41 to 26.46±4.33 degrees (P=0.009) and ACV changed from 85.97±16.07mm(3) to 99.25±15.83mm(3) (P=0.000). The changes in ACD, CCT and intraocular pressure were non-significant (P>0.05). Gonioscopy showed significant widening of the Shaffer angle in 4 quadrants (P<0.001). Pentacam can serve as the objective instrument in assessing the efficacy of LI.

Acute angle closure glaucoma is an ocular pathology characterized by a severe increase of intraocular pressure (IOP) that requires the realization of a peripheral Nd:YAG laser iridotomy as a treatment. Several complications have been described after a peripheral laser iridotomy such as hyphema, endothelial corneal damage, intraocular pressure spikes or cataract. Furthermore, retinal and subhyaloid haemorraghes have been observed after the treatment. This uncommon finding has been named decompression retinopathy. The case of an unilateral decompression retinopathy in a 67-year-old woman after the resolution of a bilateral episode of acute angle closure glaucoma was presented.

The change in the anatomical dimensions over time and the effect on diurnal intraocular pressure (DIOP) following laser peripheral iridotomy is poorly understood. To evaluate change over time in anterior chamber angle anatomy following laser peripheral iridotomy (LPI) in patients with primary angle closure compared to control eyes. Additionally, the effect of LPI on DIOP fluctuation was investigated. Longitudinal, prospective, double-randomized research study. Adults with suspected angle closure or angle closure diagnosis referred to hospital services in the United Kingdom. Thirty-nine patients newly diagnosed with bilateral primary angle closure/suspects (PAC/PACS) received LPI to one eye and changes in angle morphology were measured over eight sections with swept source AS-OCT. The other eye acted as control with intraocular pressure (IOP) measured hourly. Angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA), and trabecular-iris space area (TISA) at 500 and 750 μm from scleral spur. There was an increase in all angle parameters following LPI, which was maintained for 6 months (e.g. inferotemporal segment AOD500 0.041 mm (P = 0.008) at 1 week and 0.039 mm (P = 0.003) at 6 months) following LPI. Greatest effect at 6 months post-LPI was observed opposite the iridotomy site in the inferior/inferotemporal sections (AOD500 0.039 mm, P = 0.003 and AOD750 0.075 mm, P = 0.002). There were no statistically significant differences for the overall DIOP fluctuation values in the treated group at 6 months post-LPI compared to baseline. LPI widened all angle sections with maximum effect observed in the site opposite the iridotomy. Angle changes were maintained up to 6 months after LPI treatment without any statistically significant change in DIOP fluctuation.