Longitudinal changes in anterior chamber depth and axial length in Asian subjects after trabeculectomy surgery.

BACKGROUND/AIMS: To investigate longitudinal changes in anterior chamber depth (ACD) and axial length (AXL) over 5 years after trabeculectomy surgery in Asian patients with primary glaucoma, and to identify factors associated with these changes. METHODS: In this prospective cohort study, phakic subjects with primary glaucoma who underwent trabeculectomy had ACD and AXL measured over 5 years. The effect of intraocular pressure (IOP) on ACD and AXL was determined. Subjects were divided into two groups (high or low fluctuation of ACD/AXL) and factors were compared to determine if there were factors associated with greater fluctuation. RESULTS: 122 subjects were analysed. The majority of subjects were male (75.4%) and Chinese (77%). ACD and AXL were shallower/shorter compared with baseline at all postoperative visits, with a mean decrease of 0.11 mm (95% CI 0.07 to 0.15 mm, p<0.01) and 0.16 mm (95%CI 0.11 to 0.20 mm, p<0.01), respectively. Patients with primary open angle glaucoma (POAG) had higher odds of fluctuations in longitudinal measurements of ACD (OR=8.74, p<0.01) and AXL (OR=5.60, p<0.01) compared with patients with primary angle closure glaucoma. For every 1 mm Hg decrease in IOP, ACD and AXL decreased by 0.02 mm (p<0.01) and 0.01 mm (p=0.03), respectively, for POAG patients with emmetropia or mild myopia. CONCLUSIONS: Trabeculectomy resulted in a decrease in both ACD and AXL, and these changes were persistent over a period of 5 years.

The Singapore 5-fluorouracil trial: intraocular pressure outcomes at 8 years.

OBJECTIVE: To report the 8-year outcomes of Asian subjects who underwent trabeculectomy augmented by intraoperative 5-fluorouracil (5-FU) or placebo. DESIGN: Retrospective review of a randomized controlled trial. PARTICIPANTS: Subjects with primary open-angle or angle-closure glaucoma. METHODS: Study subjects were prospectively followed up for 3 years. After the last subject recruited had completed 8 years of follow-up, the charts of all subjects were reviewed to capture data from the year 3 visit onward. Kaplan-Meier survival function with Cox regression was performed to identify risk factors associated with trabeculectomy failure at 8 years. MAIN OUTCOME MEASURES: The primary outcome was trabeculectomy failure defined as intraocular pressure (IOP) >21 or <6 mmHg on 2 consecutive occasions after the first 6 weeks after surgery, repeat glaucoma surgery, or loss of light perception. Further end points were defined at IOP levels >17 and >14 mmHg. Secondary outcomes included IOP at 8 years and number of glaucoma medications. Complete success was defined using IOP end points ≤ 21, ≤ 17, or ≤ 14 mmHg at 8 years without medications. RESULTS: Of the 243 enrolled subjects, 170 (70.0%) completed 8 years follow-up, 86 in the 5-FU and 84 in the placebo group. There was no significant difference in failure rates at 8 years for the failure definitions of IOP >21 mmHg (11.6% of the 5-FU group vs. 16.7% of the placebo group; P = 1.00), IOP >17 mmHg (23.3% of the 5-FU group vs. 31% of the placebo group; P = 0.78), and IOP >14 mmHg (46.5% of the 5-FU group vs. 58.3% of the placebo group; P = 0.37). Mean IOP at 8 years was 13.7 mmHg in the 5-FU versus 14.4 mmHg in the placebo group (P = 0.24). Mean number of medications was 0.65 drops in the 5-FU versus 0.93 drops in the placebo group (P = 0.06). Complete success with IOP ≤ 21 mmHg at 8 years was achieved in 48 subjects (55.8%) in the 5-FU and 33 subjects (39.3%) in the placebo group (P = 0.09). Absence of bleb microcysts at 1 year, preoperative IOP, and number of bleb needlings performed within the first year were significantly associated with failure. CONCLUSIONS: There was no significant difference in IOP between the 5-FU and the placebo group at 8 years. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Initial management of acute primary angle closure: a randomized trial comparing phacoemulsification with laser peripheral iridotomy.

PURPOSE: To compare the 2-year efficacy of phacoemulsification and intraocular lens implant (phaco/IOL) with laser peripheral iridotomy (LPI) in the early management of acute primary angle closure (APAC) and coexisting cataract. DESIGN: Randomized, controlled trial. PARTICIPANTS: We included 37 subjects presenting with APAC who had responded to medical treatment such that intraocular pressure (IOP) was ≤30 mmHg within 24 hours, and had cataract with visual acuity of ≤6/15. MAIN OUTCOME MEASURES: The primary outcome measure was failure of IOP control defined as IOP between 22 to 24 mmHg on 2 occasions (readings taken within 1 month of each other) or IOP ≥25 mmHg on 1 occasion, either occurring after week 3. Secondary outcome measures were complications, degree of angle opening, amount of peripheral anterior synechiae, visual acuity, and corneal endothelial cell count (CECC). METHODS: Subjects were randomized to receive either LPI or phaco/IOL in the affected eye within 1 week of presentation and were examined at fixed intervals over 24 months. Patients underwent a standardized examination that included Goldmann applanation tonometry, gonioscopy, and CECC measurements. Logistic regression was used to estimate the effect of treatment on failure of IOP control. Time to failure was evaluated using the Kaplan-Meier technique and Cox regression was used to estimate the relative risk of failure. RESULTS: There were 18 patients randomized to LPI and 19 to phaco/IOL. The average age of subjects was 66.0±9.0 years and mean IOP after medical treatment was 14.5±6.9 mmHg. The 2-year cumulative survival was 61.1% and 89.5% for the LPI and phaco/IOL groups, respectively (P = 0.034). There was no change in CECC for either group from baseline to month 6. There was 1 postoperative complication in the phaco/IOL group compared with 4 in the LPI group (P = 0.180). CONCLUSIONS: Performed within 1 week in patients with APAC and coexisting cataract, phaco/IOL resulted in lower rate of IOP failure at 2 years compared with LPI.

Genome-wide association analyses identify three new susceptibility loci for primary angle closure glaucoma.

Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. We conducted a genome-wide association study including 1,854 PACG cases and 9,608 controls across 5 sample collections in Asia. Replication experiments were conducted in 1,917 PACG cases and 8,943 controls collected from a further 6 sample collections. We report significant associations at three new loci: rs11024102 in PLEKHA7 (per-allele odds ratio (OR)=1.22; P=5.33×10(-12)), rs3753841 in COL11A1 (per-allele OR=1.20; P=9.22×10(-10)) and rs1015213 located between PCMTD1 and ST18 on chromosome 8q (per-allele OR=1.50; P=3.29×10(-9)). Our findings, accumulated across these independent worldwide collections, suggest possible mechanisms explaining the pathogenesis of PACG.

Cataract surgery after trabeculectomy: the effect on trabeculectomy function.

OBJECTIVE: To determine whether the timing of cataract surgery after trabeculectomy has an effect on trabeculectomy function in terms of intraocular pressure control. METHODS: This was a cohort study nested within a randomized clinical trial. There were 235 participants with glaucoma who had a single previous trabeculectomy augmented with either intraoperative 5-fluorouracil or placebo. Cataract surgery with intraocular lens implantation was performed on participants judged to have significant lens opacity. Cox regression was performed to evaluate the effect of time between trabeculectomy and cataract surgery on the time to trabeculectomy failure, after adjusting for other relevant risk factors. The main outcome measure was time to failure of trabeculectomy, defined as an intraocular pressure of greater than 21 mm Hg. RESULTS: Of the 235 participants, 124 (52.7%) underwent subsequent cataract surgery. The median time from trabeculectomy to cataract surgery for these patients was 21.7 months (range, 4.6-81.9 months). The median follow-up period was 60 months (range, 28-84 months) for the cataract surgery group and 48 months (range, 12-84 months) for the non-cataract surgery group. Cox regression showed that the time from trabeculectomy to cataract surgery was significantly associated with time to trabeculectomy failure (hazard ratio, 1.73 [95% CI, 1.05-2.85]; P = .03). The adjusted declining hazard ratios for risk of subsequent trabeculectomy failure when cataract surgery was performed 6 months, 1 year, and 2 years after trabeculectomy were 3.00 (95% CI, 1.11-8.14), 1.73 (95% CI, 1.05-2.85), and 1.32 (95% CI, 1.02-1.69), respectively. CONCLUSIONS: Cataract surgery after trabeculectomy increases the risk of trabeculectomy failure, and this risk is increased if the time between trabeculectomy and cataract surgery is shorter.

Glaucoma management in patients with osteo-odonto-keratoprosthesis (OOKP): the Singapore OOKP Study.

PURPOSE: To report diagnostic modalities and treatment options for glaucoma in eyes with osteo-odonto keratoprosthesis (OOKP). METHODS: Eyes that underwent OOKP were evaluated for glaucoma at the time of the first postoperative visit, then at 1 and 3 months after the procedure, and thereafter every 6 months. All eyes underwent stereo-biomicroscopic optic nerve head (ONH) assessment, kinetic (Goldmann perimetry) and automated static visual field testing, ONH photography, Heidelberg retina tomograph, scanning laser polarimetery (GDx), and optical coherence tomography. Treatment of glaucoma was also reviewed. RESULTS: Average follow-up period was 19.1 (range: 5 to 31) months. Of the 15 eyes that underwent OOKP, 5 eyes had preexisting glaucoma. None of the other 10 eyes developed glaucoma after OOKP. ONH photography and visual field testing were the most reliable methods to assess status of the disease, whereas Heidelberg retina tomograph and optical coherence tomography could be performed with reasonable reproducibility and quality; GDx imaging was poor. All patients with glaucoma were treated with oral acetazolamide 500 mg twice a day. Transscleral cyclophotocoagulation was performed in 3 eyes at stage 2 of OOKP surgery. Progression of glaucoma was noted in 2 eyes on the basis of optic disc photographs and automated perimetry. CONCLUSIONS: Visual field testing and optic disc assessment with optic disc photographs seem to be effective methods to monitor eyes with OOKP for glaucoma. Treatment strategies include oral medications to lower intraocular pressure and cyclophotocoagulation.

The singapore 5-Fluorouracil trabeculectomy study: effects on intraocular pressure control and disease progression at 3 years.

PURPOSE: To report 3-year results of a randomized, controlled trial comparing the use of a single application of 5-fluorouracil (5-FU) with placebo in trabeculectomy surgery. DESIGN: Prospective, randomized, double-blinded treatment trial. PARTICIPANTS: Two hundred forty-three Asian patients with primary open-angle or primary angle-closure glaucoma undergoing primary trabeculectomy. METHODS: One eye of each patient was randomized to receive either intraoperative 5-FU or normal saline (placebo) during trabeculectomy. MAIN OUTCOME MEASURES: Primary outcome measure was the level of intraocular pressure (IOP). Secondary outcomes were progression of visual field loss, rates of adverse events, and interventions after surgery. RESULTS: Of the 288 eligible patients, 243 were enrolled and 228 completed 3 years follow-up; 120 patients received 5-FU and 123 received placebo. Trial failure, according to predefined IOP criteria, was lower in the 5-FU group compared with the placebo group, although the difference was only significant with a failure criterion of IOP >17 mmHg (P = 0.0154). There was no significant difference in progression of optic disc and/or visual field loss over 36 months between 5-FU and placebo (relative risk [RR], 0.67; 95% confidence interval [CI], 0.34-1.31; P = 0.239). Uveitis occurred more often in the 5-FU-treated group (14/115 [12%] vs 5/120 [4%]; P = 0.032). CONCLUSIONS: This is the first masked, prospective, randomized trial reporting the effect of adjunctive 5-FU in trabeculectomy surgery in an East Asian population. The trial shows that an increased success rate can be achieved for several years after a single intraoperative treatment with 5-FU. We conclude that 5-FU is relatively safe and can be routinely used in low-risk East Asian patients. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Confirmation of the presence of uveal effusion in Asian eyes with primary angle closure glaucoma: an ultrasound biomicroscopy study.

OBJECTIVE: To confirm the presence of uveal effusion in the eyes of Asian patients with primary angle closure glaucoma (PACG) using ultrasound biomicroscopy (UBM). METHODS: In this observational case series, 70 patients with PACG (28 untreated patients with newly diagnosed PACG and 42 patients who had undergone previous laser iridotomy and were being monitored) and 12 patients with acute primary angle closure (APAC) were recruited. Eyes of patients with newly diagnosed PACG and APAC underwent UBM before and after laser iridotomy, whereas eyes of patients with treated PACG underwent UBM at enrollment. Uveal effusion was defined as a clear space between the choroid and sclera and was graded as follows: grade 0, none; grade 1, slitlike; grade 2, bandlike; and grade 3, obvious. RESULTS: Overall, uveal effusion was found in 11 of 70 eyes with PACG (15.7%; 95% confidence interval, 8.8%-26.2%) and in 3 of 12 eyes with APAC (25%; 95% confidence interval, 8.0%-53.4%). For patients with newly diagnosed PACG, uveal effusion was found in 4 of 28 eyes (14.2%; 95% confidence interval, 5.1%-32.1%) before laser iridotomy; 2 eyes had effusion after laser iridotomy. When present, the effusion was grade 1 in PACG eyes and grade 2 or 3 in APAC eyes. CONCLUSIONS: Uveal effusion was present in a significant proportion of Asian eyes with PACG and APAC, confirming a recent report of this finding.

National survey of ophthalmologists in Singapore for the assessment and management of asymptomatic angle closure.

PURPOSE: Approximately 10% of Chinese people older than 50 years in Singapore have asymptomatic narrow angles [also termed primary angle closure suspects (PACS)]. The aim of this study was to determine the attitudes and practices of ophthalmologists in Singapore regarding the management of these patients. METHODS: A nation wide questionnaire-based survey was conducted on all registered, practicing ophthalmologists in Singapore by electronic mail and post. An ophthalmologist was defined as a doctor who had completed at least 3 years of specialist training in ophthalmology and had passed the Master's Degree in Ophthalmology or equivalent examinations. The survey asked the ophthalmologists about the methods and criteria used for the diagnosis of angle closure. It also inquired about the management of PACS and opinions on the effectiveness of prophylactic laser peripheral iridotomy (LPI) in preventing both acute and chronic angle closure. RESULTS: A total of 126 out of 158 ophthalmologists responded (79.7% response rate). Of the respondents, 84.9% would advise prophylactic LPI for asymptomatic PACS; 84.9% believed that prophylactic LPI would prevent acute angle closure but only 44% thought that it could prevent the development of glaucomatous optic nerve damage. The preferred method of prophylactic LPI was sequential argon-YAG LPI. In assessing patients for angle closure, 85.4% used gonioscopy, 92.9% assessed anterior chamber depth, and 17.5% performed provocative tests. CONCLUSIONS: Ophthalmologists in Singapore vary in the method of assessment of patients with angle closure. Most believe that prophylactic LPI should be performed for asymptomatic PACS.

Efficacy and safety of a systematic switch from latanoprost to travoprost in patients with glaucoma.

PURPOSE: To assess the efficacy and safety of systematically switching a large number of hospital-based glaucoma patients from latanoprost to travoprost therapy. MATERIALS AND METHODS: In this prospective observational study, patients on latanoprost were systematically switched to travoprost without washout and followed-up for 12 weeks. The main outcome measures were control of intraocular pressure (IOP), rate of switching back, and tolerability. IOP was measured at baseline (while on latanoprost), and at weeks 6 and 12 after switching to travoprost. Adverse effects were assessed and conjunctival hyperemia was graded using a standardized scale. RESULTS: Ninety-three consecutive patients (mean age 63.3 +/- 12.1 y) were enrolled. Nine patients were lost to follow-up. Four patients (4.3%) were switched back to latanoprost after 6 weeks due to travoprost intolerance. There was no significant difference between mean IOP at baseline [16.4 +/- 3.4 mm Hg, 95% confidence interval (CI) 15.6-17.2] and that at week 6 (15.9 +/- 4.2 mm Hg, 95% CI 14.9-16.8) (P=0.2) and week 12 (16.4 +/- 5.7 mm Hg, 95% CI 15.1-17.7) (P=0.99). There was no significant difference in the mean hyperemia score at week 12 compared with baseline (P=0.09). The majority of patients (86.9%) felt that both medications were comparable in terms of degree of comfort; 5 felt that travoprost caused more redness. CONCLUSIONS: In this study, when glaucoma patients were systematically switched from latanoprost to travoprost, the efficacy and safety of the 2 medications were found to be comparable. A high switch rate (95.2%) was achieved with average hyperemia scores being comparable.

Comparison of the scanning peripheral anterior chamber depth analyzer and the modified van Herick grading system in the assessment of angle closure.

PURPOSE: To compare the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and the modified van Herick grading system in the assessment of angle closure, using gonioscopy as the reference standard. DESIGN: Prospective comparative study. PARTICIPANTS: One hundred twenty phakic subjects (53 with primary angle closure and 67 with open angles) with no history of laser or intraocular surgery. METHODS: The modified van Herick grading system was used to grade the peripheral anterior chamber depth (ACD) clinically. The SPAC was used to assess ACD, and this was graded categorically as S (suspect angle closure), P (potential angle closure), or N (normal) and numerically from 1 to 12. One randomly selected eye of each subject underwent examination with the modified van Herick grading, SPAC, Goldmann applanation tonometry, optic disc examination, and gonioscopy. The SPAC measurements, modified van Herick grades (0%, 5%, 15%, 25%, 40%, 75%, and > or =100% of corneal thickness), and gonioscopy (graded as narrow or open) were correlated using the Spearman correlation coefficient. The receiver operating characteristics of the 2 methods to detect angle closure also were compared. MAIN OUTCOME MEASURES: Grading of ACD by the SPAC, the modified van Herick system, and gonioscopic grading of the angle. RESULTS: The SPAC results correlated well with the modified van Herick grading system (categorical grade, r = 0.527; numerical grade, r = 0.542; P<0.0001). For eyes graded as having narrow angles by gonioscopy, the area under the curve (AUC) for SPAC categorical grade S or P was 0.790; sensitivity and specificity were 84.9% and 73.1%, respectively. For the modified van Herick grading system, using a cutoff of peripheral ACD < or = 25% corneal thickness, the AUC was 0.872 and sensitivity and specificity were 84.9% and 89.6%. Compared with gonioscopy that found 53 of 120 cases of narrow angles, the SPAC graded more eyes as having narrow angles (63/120) than the modified van Herick system (52/120). CONCLUSIONS: The SPAC correlated well with the modified van Herick system in grading peripheral ACD. However, the SPAC appeared to overestimate the proportion of eyes with narrow angles relative to gonioscopy and the modified van Herick grading system.

Effect of trabeculectomy on lens opacities in an East Asian population.

OBJECTIVE: To examine the progression of lens opacity in Asian people after trabeculectomy and determine associated risk factors. METHODS: This was an observational case series of 243 people aged 36 to 82 years. Trabeculectomy was performed on 1 eye of each subject. Lens opacity was measured yearly using the Lens Opacification Classification System III. The main outcome measure was worsening of lens opacity defined as an increase of 2 or more Lens Opacification Classification System III units in any of the 3 lens regions, nuclear, cortical, and posterior subcapsular. Risk of progression was evaluated using logistic regression models. RESULTS: Data for 177 people were analyzed. One hundred seventeen (66%) of 177 subjects showed progression in opacity in any lens region at 3 years. Seventy-seven (66%) of 117 of those who progressed did so during the first year. Of these, 63 (82%) of 77 had lens opacity in the posterior subcapsular region. Factors associated with progression of posterior-subcapsular lens opacity at 1 year were diabetes (odds ratio, 2.4; 95% confidence interval, 1.0-5.4), use of antiglaucoma medication, dosage of topical steroid postoperatively, and being operated on by a trainee surgeon (odds ratio, 2.3; 95% confidence interval, 1.0-5.2). CONCLUSIONS: Trabeculectomy is associated with progression of lens opacity predominantly in the posterior subcapsular region. Modification of risk factors such as postoperative steroid use may delay progression.

Iris ischaemic changes and visual outcome after acute primary angle closure.

BACKGROUND: Ischaemic changes in the iris occur frequently after an episode of acute primary angle closure (APAC). The aim of this study was to investigate the significance of such changes with regards to visual outcome. METHODS: Acute primary angle closure cases were treated with medical therapy followed by laser peripheral iridotomy after resolution of the acute episode. Subjects were examined at 1, 4, 8, 12 and 16 weeks post laser peripheral iridotomy. Eyes were examined for signs of iris ischaemic changes (IIC), defined as the presence of iris whorling or stromal atrophy. Iris photographs were also taken at weeks 1, 8 and 16. Subjects requiring glaucoma medication or filtering surgery during the follow-up period were excluded. The visual acuity and visual field (using automated white-on-white threshold perimetry) at week 16 were used in the assessment of visual outcome. RESULTS: Sixty-one subjects with APAC completed the study. The majority of subjects were female (82%) and Chinese (92%), and the mean age was 59 +/- 8.8 years. More than half the subjects (52.5%) were found to have developed IIC during the study, 65% of whom already had signs of IIC by the first week. Only 13 subjects (41%) with IIC and 6 subjects (21%) without IIC had an abnormal visual field defect at week 16 (P = 0.09). There was also no difference in visual acuity at week 16, the majority of subjects in both groups having visual acuity of 6/12 or better. CONCLUSIONS: The development of iris ischaemic changes after a single episode of APAC may not be associated with an adverse visual outcome.

Use of surodex in phacotrabeculectomy surgery.

PURPOSE: To evaluate the use of Surodex (Oculex Pharmaceuticals, Sunnyvale, California) a drug delivery system incorporating 60 micrograms of dexamethasone in a pellet, in phacotrabeculectomy surgery. DESIGN: Nonrandomized, prospective, interventional case series. METHODS: Phacotrabeculectomy was performed on 37 Asian subjects with primary open-angle glaucoma (POAG) using a standardized technique. All subjects received a Surodex pellet underneath the scleral flap. Results were compared with those of 31 POAG subjects who had undergone phacotrabeculectomy augmented with 50 mg/ml of intraoperative 5-fluorouracil (5-FU) during the same period. RESULTS: Mean follow-up in months was 19.7 +/- 7.9 and 22.1 +/- 6.2 for the Surodex and 5-FU groups, respectively (P = .29). There was a 20.1% decrease in intraocular pressure in the Surodex group compared with 28.5% decrease in the 5-FU group (P = .6). Postoperative complications occurred in three cases (8.1%) and six cases (19.3%), respectively (P = .04). CONCLUSIONS: Combined phacotrabeculectomy surgery augmented by intra-scleral placement of Surodex results in good control of IOP and a low incidence of complications.

The severity and spatial distribution of visual field defects in primary glaucoma: a comparison of primary open-angle glaucoma and primary angle-closure glaucoma.

OBJECTIVE: To compare the characteristics of visual field defects in primary angle-closure glaucoma (PACG) and primary open-angle glaucoma (POAG). METHODS: Subjects with primary glaucoma aged 30 years and older were prospectively considered for inclusion. Automated static white-on-white perimetry was performed. A minimum of 2 reliable tests was required with a mean deviation (MD) within 2 dB on 2 tests. Subjects with previous symptomatic angle-closure, normal-tension glaucoma, visually significant cataract, or previous intraocular surgery were excluded. RESULTS: Of 234 subjects assessed, 129 had POAG, and 105 had PACG. The MDs (POAG group, -13.3 dB; PACG group, -18.0 dB) indicated more severe visual loss in subjects with PACG. In subjects with POAG, the superior hemifield was more severely affected than the inferior. This was less pronounced in subjects with PACG. Following stratification by MD, the difference between hemifields was marked in the mild (-10 dB

Additive effect of unoprostone and latanoprost in patients with elevated intraocular pressure.

AIMS: To assess the additive effect of unoprostone and latanoprost in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT) METHODS: 32 patients with POAG or OHT were randomised to receive either latanoprost once daily or unoprostone twice daily for 4 weeks. After 4 weeks, all patients received both latanoprost and unoprostone for another 4 weeks. The IOP was measured at 9 am and 5 pm on the baseline, day 28, and day 56 visits, and at 9 am on day 14 and day 42 visits. The medications were given to the patients in an open label fashion. The observer was masked to the treatment given. The mean of the measurements was calculated. Safety parameters were also recorded. The additive effect of the medications was assessed by the reduction in intraocular pressure (IOP) when both medications were used, compared with when one medication was used. RESULTS: 28 patients completed both treatment periods and had IOP data available for evaluation. After 1 month of treatment, latanoprost significantly reduced IOP (mean by 6.1 (SEM 0.8) mm Hg (p<0.001) and unoprostone by 4.9 (1.0) mm Hg (p<0.001) from the baseline of 24.4 (0.6) mm Hg and 24.4 (1.1) mm Hg respectively (p = 0.18). When latanoprost once daily was given to patients treated with unoprostone, there was additional IOP lowering of 1.9 (0.6) mm Hg (p = 0.012). However, adding unoprostone to those being treated with latanoprost produced an IOP change of +0.4 (0.5) mm Hg (p = 0.42). Ocular symptoms and findings were mild and equally distributed between treatment groups, and after combined therapy. Hyperaemia and ocular irritation were the most frequently reported events. Over a third of patients experienced ocular irritation with the combination of medications. CONCLUSIONS: Latanoprost once daily causes additional IOP lowering in eyes which were being treated with unoprostone twice a day. However, there was no additional IOP lowering when unoprostone was added to eyes which were being treated with latanoprost. Both drugs were well tolerated together with few ocular adverse events.