John K. H. Chua

Five‐year follow up of selective laser trabeculoplasty in Chinese eyes

Purpose: To study the effectiveness and safety of selective laser trabeculoplasty (SLT) on primary open‐angle glaucoma and ocular hypertension in Chinese eyes.

Argon laser peripheral iridoplasty versus conventional systemic medical therapy in treatment of acute primary angle-closure glaucoma: A prospective, randomized, controlled trial

OBJECTIVE To study whether argon laser peripheral iridoplasty (ALPI) is as effective and safe as conventional systemic medications in treatment of acute primary angle-closure glaucoma (PACG) when immediate laser peripheral iridotomy is neither possible nor safe. DESIGN Prospective, randomized, controlled trial. PARTICIPANTS Seventy-three eyes of 64 consecutive patients with their first presentation of acute PACG, with intraocular pressure (IOP) levels of 40 mmHg or more, were recruited into the study. INTERVENTION The acute PACG eye of each consenting patient received topical pilocarpine (4%) and topical timolol (0.5%). The patients were then randomized into one of two treatment groups. The ALPI group received immediate ALPI under topical anesthesia. The medical treatment group was given 500 mg of intravenous acetazolamide, followed by oral acetazolamide 250 mg four times daily, and an oral potassium supplement until IOP levels normalized. Intravenous mannitol also was administered to the latter group if the presenting IOP was higher than 60 mmHg. The acute PACG eye of both groups continued to receive topical pilocarpine (1%) until peripheral iridotomy could be performed. MAIN OUTCOME MEASURES Intraocular pressure profile, corneal clarity, symptoms, visual acuity, angle status by indentation gonioscopy, and complications of treatment. RESULTS Thirty-three acute PACG eyes of 32 patients were randomized to receive immediate ALPI, whereas 40 acute PACG eyes of 32 patients had conventional systemic medical therapy. Both treatment groups were matched for age, duration of attack, and IOP at presentation. The ALPI-treated group had lower IOP levels than the medically treated group at 15 minutes, 30 minutes, and 1 hour after the start of treatment. The differences were statistically significant. The difference in IOP levels became statistically insignificant from 2 hours onward. The duration of attack did not affect the efficacy of ALPI in reducing IOP in acute PACG. No serious laser complications occurred, at least in the early postlaser period. CONCLUSIONS Argon laser peripheral iridoplasty significantly is more effective than conventional systemic medications in reducing IOP levels in acute PACG in eyes not suitable for immediate laser peripheral iridotomy within the first 2 hours from the initiation of treatment. Argon laser peripheral iridoplasty is a safe and more effective alternative to conventional systemic medications in the management of acute PACG not amenable to immediate laser peripheral iridotomy.

Efficacy and safety of immediate anterior chamber paracentesis in the treatment of acute primary angle-closure glaucoma: a pilot study.

OBJECTIVE To study the safety and effectiveness of immediate anterior chamber paracentesis, combined with antiglaucomatous medications, in the intraocular pressure control and relief of symptoms of acute primary angle-closure glaucoma (PACG). DESIGN Prospective noncomparative case series. PARTICIPANTS Eight consecutive patients with their first attack of acute PACG, with intraocular pressure > or =50 mmHg, were recruited into the study. INTERVENTION On presentation, each patient received topical pilocarpine (4%) and timolol (0.5%), immediate anterior chamber paracentesis, and systemic acetazolamide and mannitol as primary treatment. The intraocular pressures at 15 and 30 minutes, and then at 1, 2, 3, 12, and 24 hours, were documented by applanation tonometry. MAIN OUTCOME MEASURES Symptoms, visual acuity, intraocular pressure, corneal edema, angle status on gonioscopy, pupillary size, and reaction. RESULTS Ten eyes of eight patients seen with acute PACG were recruited. The mean intraocular pressure was reduced from 66.6 +/- 9.1 mmHg to 15.1 +/- 3.5 mmHg immediately after paracentesis, and then to 17.1 +/- 7.0 mmHg at 15 minutes, 21.7 +/- 10.2 mmHg at 30 minutes, 22.7 +/- 11.0 mmHg at 1 hour, and 20.1 +/- 14.6 mmHg at 2 hours after paracentesis. The mean intraocular pressure was less than 21 mmHg at 2 hours and beyond. There was instant symptomatic relief for all patients. No complications from the paracentesis were encountered. CONCLUSIONS From this preliminary study, immediate paracentesis seems to be safe and effective in controlling the intraocular pressure and eliminating symptoms in acute PACG.

Efficacy and safety of the Ahmed glaucoma valve implant in Chinese eyes with complicated glaucoma

AIMS To evaluate the efficacy and safety of the Ahmed glaucoma valve implant in Chinese eyes with complicated glaucomas. METHODS This retrospective study reviewed the final intraocular pressure, visual outcome, and incidence of complications in all patients with the Ahmed glaucoma valve implant performed at the Prince of Wales Hospital, Hong Kong, between June 1996 and November 1998. RESULTS A total of 65 eyes from 60 patients were treated with the Ahmed glaucoma implant. At a mean follow up (SD, median) of 21.8 (9.2, 28.0) months (range 6–37 months), the mean intraocular pressure was reduced from 37.0 (SD 12.1) mm Hg before the implant surgery to 16.1 (12.4) mm Hg at the last follow up after surgery. The success rate of intraocular pressure control of <22 mm Hg was achieved in 73.8% of operated eyes. Transient postoperative hypotony with shallow anterior chamber occurred in 10.8% of cases. The most common postoperative complication was the formation of encapsulated bleb (24.6%). CONCLUSIONS The Ahmed glaucoma valve implant appears to be effective and relatively safe for treating complicated glaucomas in Chinese eyes. The success rate is comparable with those reported in non-Asian eyes. Formation of postoperative encapsulated bleb is, however, more commonly encountered.

Short-term results of scleral intraocular lens fixation in children

Purpose: To study the safety and efficacy of scleral intraocular lens (IOL) fixation in children. Setting: A university practice. Methods: This retrospective review evaluated the results and complications in 6 consecutive eyes of 3 children who had anterior vitrectomy, with or without lensectomy, and scleral IOL fixation to correct ectopia lentis or aphakia. Results: At a mean follow‐up of 17.3 months (range 13 to 21 months), all eyes had a stable and well‐positioned posterior chamber IOL and good visual improvement. The only complication was asymptomatic pupillary capture of the IOL in 3 eyes. Reversal of the pupillary capture was achieved by pupil dilation with the patient in a supine position. Conclusions: The preliminary results of scleral IOL fixation in children are encouraging. The procedure’s application in well‐selected cases can be considered. However, its long‐term safety and efficacy must be further assessed through studies with larger sample sizes and a longer follow‐up.

Re: laser peripheral iridoplasty as initial treatment of acute attack of primary angle-closure: a long-term follow-up study.

PurposeTo study the long-term clinical course and complications of patients with acute primary angle-closure treated with immediate laser peripheral iridoplasty followed by laser peripheral iridotomy. Patients and MethodsConsecutive patients with acute primary angle closure treated with immediate laser peripheral iridoplasty, followed by laser peripheral iridotomy, at the Prince of Wales Hospital from July 1997 through January 2000 were followed up to document the clinical course of their disease and any complications from the laser treatment. Visual acuity, intraocular pressure, gonioscopic findings, corneal and lens clarity, iris appearance, pupillary reaction, and progression of glaucomatous optic neuropathy were evaluated. ResultsThirty eyes of 29 Chinese patients with acute primary angle closure treated initially with either argon or diode laser peripheral iridoplasty were recruited. The mean follow-up period was 33.0 ± 9.3 months. Twenty-one eyes (70%) had no further attack and maintained normal intraocular pressure without medications, and 9 eyes (30%) developed chronic angle-closure glaucoma with peripheral anterior synechiae. All eyes had pigmented laser marks on the peripheral iris, but none had peripheral corneal burn. ConclusionsLong-term follow-up data indicated that 30% of Chinese eyes with acute primary angle closure successfully treated with immediate laser peripheral iridoplasty followed by laser peripheral iridotomy developed peripheral anterior synechiae and an increase in intraocular pressure. There were minimal long-term complications on the cornea and the lens from the laser treatment.

Efficacy and safety of inferior 180 degrees goniosynechialysis followed by diode laser peripheral iridoplasty in the treatment of chronic angle-closure glaucoma.

PURPOSE To report the efficacy and safety of inferior 180 degrees goniosynechialysis followed by diode laser peripheral iridoplasty in the treatment of chronic angle-closure glaucoma with total synechial angle closure. METHODS Five patients with chronic angle-closure glaucoma and total synechial angle closure whose intraocular pressures were higher than 21 mm Hg while taking maximally tolerated medications underwent goniosynechialysis followed by diode laser peripheral iridoplasty to the inferior half of the angle. Intraoperative complications, postoperative visual acuity, intraocular pressures, and complications were evaluated. RESULTS Five eyes of five patients received the operation and the mean follow-up was 7.6 months (range, 6-12 months). The mean preoperative intraocular pressure was 33.8 +/- 5.8 mm Hg. The mean postoperative intraocular pressure at most recent follow-up was 15.8 +/- 2.2 mm Hg. Postoperative complications included transient increase in intraocular pressure, hyphema, and cataract. The success rate (intraocular pressure less than 20 mm Hg with or without medication) was 80.0%. CONCLUSION It appears that 180 degrees goniosynechialysis followed by diode laser peripheral iridoplasty is an effective and safe surgical procedure for treating chronic angle-closure glaucoma with total synechial angle closure.

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

PurposeTo study the safety and efficacy of immediate argon laser peripheral iridoplasty (ALPI) as initial treatment of acute phacomorphic angle-closure (phacomorphic glaucoma) before cataract extraction.MethodsIn all, 10 consecutive patients with acute phacomorphic angle-closure and intraocular pressure (IOP) ⩾40 mmHg were recruited into the study. Each patient received topical atropine (1%) and timolol (0.5%), and immediate ALPI as initial treatment. The IOP at 15, 30, 60, and 120 min, and then 1 day, after ALPI were documented by applanation tonometry. Systemic IOP-lowering drugs were only started if IOP remained above 40 mmHg at 2 h after ALPI. Cataract extraction was subsequently performed as definitive treatment.ResultsIn total, 10 patients (five male, five female), with a mean age±SD of 73.1±10.3 years were recruited. Mean duration of symptomatic attack was 128±232 h. After ALPI, the mean IOP was reduced from 56.1±12.5 to 45.3±14.5 mmHg at 15 min, 37.6±7.5 mmHg at 30 min, 34.2±9.7 mmHg at 60 min, 25.5±8.7 mmHg at 120 min, and 13.6±4.2 mmHg at 1 day. In one patient, systemic acetazolamide was administered, because the IOP remained above 40 mmHg at 2 h after ALPI. All 10 patients had uncomplicated cataract extraction performed within 4 days after ALPI. No complications from the laser procedure were encountered.ConclusionImmediate ALPI, replacing systemic antiglaucomatous medications, appeared to be safe and effective as first-line treatment of acute phacomorphic angle-closure.

Latanoprost versus timolol gel to prevent ocular hypertension after phacoemulsification and intraocular lens implantation

PURPOSE To evaluate the efficacy of latanoprost and timolol gel in preventing ocular hypertension in the early period after phacoemulsification and posterior chamber intraocular lens (PC IOL) implantation. SETTING Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong, China. METHODS This prospective randomized double-masked clinical trial comprised patients with uncomplicated cataract having phacoemulsification with PC IOL implantation. They were randomly assigned to 1 of 3 groups: postoperative application of timolol 0.5% gel-forming solution (Timoptol-XE(R)) (Group 1), latanoprost 0.005% (Group 2), and control (Group 3). Intraocular pressure (IOP) was measured 2, 4, and 24 hours postoperatively. The anterior chamber was examined for the levels of cells and flare using slitlamp biomicroscopy. RESULTS Group 1 had a significantly greater reduction in mean IOP 2, 4, and 24 hours after phacoemulsification and PC IOL implantation than Group 3 (P <.05). There were no significant differences between Groups 2 and 3 at any interval (P. 05). No excessive postoperative anterior chamber inflammation was observed in any group. CONCLUSIONS A single dose of latanoprost given after phacoemulsification and PC IOL implantation did not produce a significant IOP-lowering effect when compared with a control group in the first 24 hours postoperatively. A single dose of timolol gel produced a significant postoperative IOP decrease as soon as 2 hours and up to 24 hours after surgery. Timolol gel and latanoprost are safe, but timolol is more effective than latanoprost in preventing postoperative ocular hypertension.

To compare argon laser peripheral iridoplasty (ALPI) against systemic medications in treatment of acute primary angle-closure: mid-term results

PurposeTo compare the clinical outcome of argon laser peripheral iridoplasty (ALPI) against systemic medications in treatment of acute primary angle-closure (APAC).MethodsConsecutive patients with APAC were recruited and randomized to receive one of two treatment options: immediate ALPI or systemic acetazolamide±mannitol. All eyes were followed up for at least 6 months after laser iridotomy. Main outcome measures were intraocular pressure (IOP) and requirement for glaucoma medications.ResultsA total of 41 eyes (39 patients) were randomized into the ALPI group, and 38 eyes (32 patients) into the medical treatment group. There were no significant differences between the two groups in sex, age, presenting IOP, and duration of attack. Mean follow-up duration±SD was 15.7±5.8 months. There were no significant differences between the two groups in mean final IOP and requirement for glaucoma medications.ConclusionsThere were no statistically significant differences in mean IOP and requirement for glaucoma drugs between APAC eyes treated with ALPI and systemic medications.