Jonathan C.H. Chan

The clinical outcomes of cataract extraction by phacoemulsification in eyes with primary angle-closure glaucoma (PACG) and co-existing cataract: a prospective case series.

Purpose:To evaluate the clinical outcomes of minimally invasive cataract extraction by phacoemulsification, with primary intraocular lens implantation, in eyes with primary angle-closure glaucoma (PACG) and co-existing cataract. Materials and Methods:Consecutive primary angle-closure glaucoma patients with co-existing visually significant cataract were invited to participate in this prospective study. After obtaining informed consent, cataract extraction by phacoemulsification through a clear corneal incision was performed under topical anesthesia. Foldable intraocular lenses were implanted in the same setting. These patients were then followed up for a minimum of 1 year. Outcome measures included intraocular pressure (IOP), requirement for glaucoma drugs, and visual acuity. Results:Twenty-one primary angle-closure glaucoma eyes of 21 patients were recruited. Mean age (± SD) was 73.7 ± 8.1 years (range, 60-87 years). There were 12 female patients and 9 male patients, with 13 right eyes and 8 left eyes. Nine eyes (42.9%) had history of acute primary angle closure. Mean follow-up duration was 20.7 ± 3.6 months (range, 13-26 months). Intraocular pressure was decreased from a mean preoperative level of 19.7 ± 6.1 mm Hg (range, 11 mm Hg-40 mm Hg) to 15.5 ± 3.9 mm Hg (range, 9 mm Hg-26 mm Hg) at final follow-up (P = 0.022) (paired t test). The number of glaucoma eye drops required was decreased from a mean preoperative level of 1.91 ± 0.77 (range, 1-3) to 0.52 ± 0.87 (range, 0-3) at final follow-up (P < 0.001) (paired t test). In 10 eyes (47.6%), visual acuity improved significantly after surgery. In 9 eyes (42.9%), visual acuity remained the same. In 2 eyes (9.5%), visual acuity deteriorated significantly after surgery. Mean cup-to-disc ratio was 0.6 ± 0.2 (range, 0.3-0.9) preoperatively, and 0.7 ± 0.2 (range, 0.3-0.9) postoperatively (P = 0.047) (paired t test). Conclusions:In primary angle-closure glaucoma patients with co-existing cataract, cataract extraction alone (by phacoemulsification) can significantly reduce both intraocular pressure and the requirement for glaucoma drugs.

Phacoemulsification vs phacotrabeculectomy in chronic angle-closure glaucoma with cataract complications

OBJECTIVE To compare the complications of phacoemulsification alone vs combined phacotrabeculectomy in chronic angle-closure glaucoma (CACG) with coexisting cataract. METHODS Patients with CACG with coexisting cataract recruited into 2 randomized controlled trials comparing phacoemulsification alone vs combined phacotrabeculectomy were pooled for analysis. The first trial recruited patients with medically controlled intraocular pressure, while the second trial recruited patients with medically uncontrolled intraocular pressure. The 2 trials had otherwise identical study designs. All patients were reviewed every 3 months for 2 years after surgery. The main outcome measure was the surgical complications of phacoemulsification alone vs combined phacotrabeculectomy in CACG eyes with cataract. RESULTS One hundred twenty-three CACG eyes with cataract from 123 patients were included. Sixty-two CACG eyes were randomized to receive phacoemulsification alone, and 61 eyes had combined phacotrabeculectomy. In the phacoemulsification group, 5 of the 62 CACG eyes (8.1%) had a total of 5 surgical complications. In the combined phacotrabeculectomy group, 16 of the 61 CACG eyes (26.2%) had a total of 19 surgical complications. The difference in the proportion of eyes with 1 or more surgical complications between the 2 treatment groups was statistically significant (P = .007, Pearson chi(2) test). There was no statistically significant difference in final visual acuity or glaucomatous progression during the 24-month follow-up. CONCLUSIONS Combined phacotrabeculectomy resulted in significantly more surgical complications than phacoemulsification alone in CACG eyes with coexisting cataract. There was no difference in visual acuity or disease progression between the 2 treatment groups.

Diode laser transscleral cyclophotocoagulation as primary surgical treatment for medically uncontrolled chronic angle closure glaucoma: long-term clinical outcomes.

Purpose:To evaluate the long-term efficacy and safety of diode laser transscleral cyclophotocoagulation as primary surgical treatment of medically uncontrolled chronic angle closure glaucoma. Patients and Methods:Thirteen eyes of 13 Chinese patients with medically uncontrolled chronic angle closure glaucoma were treated with diode laser transscleral cyclophotocoagulation between February 2000 and May 2001, and followed up for over 18 months. Post-treatment anti-glaucoma medications were adjusted according to intraocular pressure. If intraocular pressure remained above 21 mm Hg despite medications for more than 4 weeks after cyclophotocoagulation, the procedure was repeated. Results:Mean follow-up ± SD was 26.5 ± 4.2 months. Two eyes required repeat cyclophotocoagulation at 6 weeks. Rate of relative success, defined as maintaining an intraocular pressure of 21 mm Hg or below with or without medications, was 92.3% (12 of 13 eyes). Rate of absolute success, defined as maintaining an intraocular pressure of 21 mm Hg or below without medications, was 0% (0 of 13 eyes). Mean ± SD intraocular pressure was reduced from 36.4 ± 12.6 mm Hg pre-operatively, to 18.7 ± 12.2 mm Hg at final follow-up (P = 0.003, paired t test). The mean ± SD number of intraocular pressure-lowering eye drops was reduced from 2.0 ± 0.8 pre-operatively, to the lowest point of 0.5 ± 0.8 at 12 months, and then gradually increased to 2.1 ± 0.9 at final follow-up. The visual acuity improved after treatment in 2 of 13 eyes (15.4%), remained unchanged in 6 of 13 eyes (46.2%) and deteriorated in 5 of 13 eyes (38.5%). No major complications were encountered. Conclusion:Diode laser cyclophotocoagulation appeared to be an effective and safe primary surgical treatment of medically uncontrolled chronic angle closure glaucoma, with intraocular pressure-lowering effect persisting for up to two years.

Efficacy of selective laser trabeculoplasty for normal tension glaucoma: 1 year results

BackgroundNormal tension glaucoma (NTG) is commonly treated with anti-glaucoma medications. Recently, selective laser trabeculoplasty (SLT) has been demonstrated to lower the intraocular pressure (IOP) and medication use in NTG. The purpose of this study was to investigate the efficacy of a single session of SLT for NTG at 1 year.MethodsThis prospective cohort study recruited NTG patients taking anti-glaucoma medication. Potential subjects were excluded if they had had previous glaucoma surgery or laser and also if intraocular surgery or additional SLT procedures were performed after the first treatment. All subjects underwent a 1-month washout. A 30% IOP reduction was set as the target IOP. A single session of SLT was performed to 360 degrees of the trabecular meshwork. At 1-month after SLT, medication was resumed to achieve the target IOP. The IOP was measured every 3 months, and the number of medications was recorded at 3, 6, and 12 months. Only the right eye was used for statistical analysis.ResultsIn 41 right eyes, the mean pre-study IOP was 14.3 ± 3.4 mmHg while on 1.5 ± 0.8 eye drops. The post-washout IOP was 16.2 ± 2.2 mmHg. A mean of 191.1 ± 26.3 SLT shots at 1.0 ± 0.07 mJ were applied. There was significant IOP reduction at all time intervals following SLT when compared to the post-washout IOP (P < 0.0001). The number of medications was significantly reduced at all time intervals following SLT when compared to the pre-study level (P < 0.0001). At 12 months, the mean IOP was 12.2 ± 2.2 mmHg while on 1.1 ± 0.9 eye drops.ConclusionsA single session of SLT for NTG achieved an additional 15% IOP reduction while using 27% less medication at 1 year compared to pre-study levels.Trial registrationThe Clinical Trials Register of the University of Hong Kong HKCTR1847The European Clinical Trials Database 2014-003305-15 (August 11, 2014) (https://www.clinicaltrialsregister.eu/ctr-search/search?query=2014-003305-15)

Prospective study on the efficacy of treating normal tension glaucoma with a single session of selective laser trabeculoplasty.

Purpose:The purpose of this study was to investigate the efficacy of selective laser trabeculoplasty (SLT) in the treatment of normal tension glaucoma (NTG). Methods:This prospective cohort study recruited consecutive cases of NTG on antiglaucoma medication. Cases were excluded for previous glaucoma surgery or laser. All patients underwent a 1-month washout of medication followed by a mean baseline intraocular pressure (IOP) measured at 9 AM, 1 PM, and 5 PM. A 30% reduction from baseline was set as the target IOP. A single session of SLT was performed to 360 degrees of the trabecular meshwork. IOP phasing was repeated at 1 month after SLT and medication was resumed to achieve the target IOP. Patients were followed up to 6 months after SLT. Results:In 83 eyes of 46 subjects, the mean prestudy IOP was 14.2±3.1 mm Hg when on 1.5±0.9 antiglaucoma medication. The mean baseline IOP without medication was 16.1±2.2 mm Hg. The mean SLT shots applied was 187.8±27.5 using a mean energy of 1.0±0.07 mJ. At 1-month post-SLT, the IOP was 12.7±2.0 mm Hg (21.6% IOP reduction) from baseline without medication (P<0.05). The 6-month IOP was 11.4±1.6 mm Hg when on 1.1±1.0 medications, representing a 19.7% reduction from prestudy IOP, a 29.6% reduction from baseline IOP, and a 26.7% reduction in antiglaucoma medication (all P<0.05). A higher baseline IOP was correlated with greater IOP reduction with SLT (r=0.3, P=0.009). Conclusions:A single session of SLT for NTG achieved an additional 20% reduction in IOP with 27% less medication at 6 months compared with prestudy levels while maintaining a 30% reduction from baseline IOP.

Phacotrabeculectomy in Treatment of Primary Angle-closure Glaucoma and Primary Open-angle Glaucoma

PurposeTo evaluate the surgical outcome of combined phacoemulsification, posterior chamber intraocular lens implantation, and trabeculectomy (phacotrabeculectomy) in patients with primary angle-closure glaucoma (PACG) or primary open-angle glaucoma (POAG).MethodsThe records of 57 consecutive patients (65 eyes) with PACG or POAG that were treated with phacotrabeculectomy were reviewed retrospectively. There were 31 eyes with PACG and 34 with POAG. The mean follow-up period was 21.0 ± 8.3 months. The visual acuity, intraocular pressure (IOP), number of medications, and complications were evaluated.ResultsThe mean IOP and the number of glaucoma medications decreased significantly after phacotrabeculectomy in both groups. The mean IOP reduction was significantly greater in eyes with PACG (P < 0.05). The absolute success rates were 87.1% and 70.6% in PACG and POAG, respectively. The difference in the success rates was not significant (P = 0.297). The early postoperative complication rates were similar in both groups.ConclusionsPhacotrabeculectomy results in greater IOP reduction in eyes with PACG than in those with POAG, but the overall success rates were not significantly different.

Twenty-Four-Hour Intraocular Pressure Related Changes Following Adjuvant Selective Laser Trabeculoplasty for Normal Tension Glaucoma

AbstractTo investigate intraocular pressure (IOP) related patterns before and after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG).In this prospective cohort study, 18 NTG patients underwent SLT. Success was defined as IOP reduction ≥20% by Goldmann applanation tonometry. 24-hour IOP-related pattern recording with a contact lens sensor (CLS) (SENSIMED Triggerfish®, Sensimed, Switzerland) was done before (baseline) and 1 month after SLT. A cosine function was fitted to the mean CLS patterns for each individual in the SLT success and non-success groups and the amplitude before and after SLT was calculated. Diurnal, nocturnal, and 24-hour CLS pattern local variability was determined for pre- and post-SLT sessions. Cosine amplitude and variability were compared before and after SLT by group using paired t-tests, with &agr; = 0.05.Patients (11 women, 7 men) had a mean age of 65.1 ± 13.7 years. Mean IOP was 15.3 ± 2.2 mm Hg at baseline and was reduced by 17.0% to 12.7 ± 1.8 mm Hg 1 month after SLT (P = 0.001). SLT was successful in 8 patients (44%). The amplitude of the fitted cosine was reduced by 24.6% in the success group, but displayed an amplitude increase of 19.2% post-SLT in the non-success group. Higher diurnal local variability of the CLS pattern was observed after SLT in non-success subjects (P = 0.002), while nocturnal variability showed no significant change. The increase in diurnal variability in the non-success group led to an increase in 24-hour variability in this group (P = 0.001). No change in local variability (diurnal, nocturnal, and 24-hour) was seen in the success group.The IOP-related pattern cosinor amplitude was reduced in NTG patients with a successful SLT treatment whereas the non-success group exhibited an increase of cosine amplitude. Higher diurnal and 24-hour CLS pattern variability was observed in non-success patients 1 month post-SLT.

Comparison of postoperative refractive outcome in phacotrabeculectomy and phacoemulsification with posterior chamber intraocular lens implantation.

Purpose:To compare the postoperative refractive outcomes following phacotrabeculectomy and phacoemulsification with posterior chamber intraocular lens implantation. Methods:A retrospective comparative study of 90 consecutive patients (95 eyes) with cataract with or without co-existing glaucoma who had undergone uncomplicated phacotrabeculectomy or phacoemulsification by a single surgeon. The biometry prediction error was determined for each case by the difference between the actual postoperative refraction and the preoperative predicted refractive outcome, in spherical equivalent. This was followed by a comparative analysis of the mean biometry prediction error, and the number of cases with error >0.50 D or 1.00 D. All biometry measurements were performed by one of the two qualified optometrists. Results:The mean and absolute mean biometry prediction error of the 25 eyes that received phacotrabeculectomy (+0.20 D, absolute error 0.96 D) was comparable to the 70 eyes that received phacoemulsification (−0.14 D, absolute error 0.68 D), P = 0.18 (absolute error, P = 0.12). The proportion of cases with prediction error >0.50 D or 1.00 D was 60% or 40% for phacotrabeculectomy, and 44% or 17% for phacoemulsification, respectively. Phacotrabeculectomy was more likely to have a prediction error >1.00 D (P = 0.02) and a myopic shift of >0.50 D or 1.00 D (P = 0.03 or 0.02, respectively). No significant differences were found with regard to the frequency of hyperopic shift or prediction error >0.50 D. There was no significant difference in either the mean error or the frequency of the different types of error for the different biometry operators, types of glaucoma, or postoperative intraocular pressure control success status. Conclusion:Myopically shifted prediction error was significantly more frequent following posterior chamber intraocular lens implantation with phacotrabeculectomy compared with phacoemulsification, even when surgery was uncomplicated and performed by the same surgeon.

Predictors of success in selective laser trabeculoplasty for chinese open-angle glaucoma

Aim:To investigate the determinants of success of selective laser trabeculoplasty (SLT) in Chinese open-angle glaucoma patients. Methods:This prospective cohort study sequentially recruited Chinese subjects with unilateral or bilateral primary open-angle glaucoma (POAG) or normal tension glaucoma (NTG). All subjects received a single session of 360-degree SLT treatment. Success was defined as IOP reduction ≥20%. The following were analyzed in univariate and multivariate regression analyses for association with SLT success: type of glaucoma, age, sex, lens status, presenting IOP, pre-SLT IOP, day 1 IOP, 1-week IOP, number and type of anti-glaucoma medications, number of SLT shots and energy, retinal nerve fiber layer (RNFL) thickness, Visual Field Index, endothelial cell count, central corneal thickness, Snellen visual acuity, and spherical equivalent. Results:In 111 eyes of 65 subjects, there were 51 POAG eyes and 60 NTG eyes. The overall success was 53.15% with a mean IOP reduction of 19.81±15.93%. In univariate analysis, a thinner RNFL [coefficient=−0.027; odds ratio (OR)=0.95; P=0.017] was associated with success. In multivariate analysis, a lower day 1 IOP (coefficient=−0.29; OR=0.75; P=0.049) and using topical carbonic anhydrase inhibitors (CAI) (coefficient=2.92; OR=18.63; P=0.0020) were associated with success. In both univariate and multivariate analyses, a higher pre-SLT IOP significantly predicted success (coefficient=0.20/0.46; OR=1.23/1.58; P=0.0017/0.0011) and using 3 anti-glaucoma medications (coefficient=−1.08/−3.74; OR=0.3/0.024; P=0.037/P=0.0081) was associated with SLT failure. Conclusion:The positive predictors of SLT success included: higher pre-SLT IOP, use of topical CAI, thinner RNFL, and lower day 1 IOP. Using 3 anti-glaucoma medications was associated with failure.

Predictors of success in selective laser trabeculoplasty for primary open angle glaucoma in Chinese

Purpose To determine the predictors of success for adjuvant selective laser trabeculoplasty (SLT) in Chinese primary open angle glaucoma (POAG) patients. Methods This prospective study recruited Chinese subjects with unilateral or bilateral POAG currently taking medication to reduce intraocular pressure (IOP). All subjects received a single session of 360° SLT treatment and continued their medications for 1 month. SLT success was defined as IOP reduction ≥20% at 1 month. The following covariates were analyzed in both groups via univariate and multivariate analyses: age, sex, lens status, initial IOPs, post-SLT IOPs, number and type of medications, SLT shots and energy, and pre-SLT investigations. Results In 51 eyes of 33 POAG subjects, the success rate of SLT was 47.1%. Certain groups of patients were associated with greater success using univariate analysis. These groups included the following: older age (coefficient =0.1; OR: 1.1; P=0.0003), a higher pre-SLT IOP (coefficient =0.3; OR: 1.3; P=0.0005), using four types of antiglaucoma medication (coefficient =2.1; OR: 8.4; P=0.005), a greater degree of spherical equivalent (coefficient =2.1; OR: 8.4; P=0.005), and the use of a topical carbonic anhydrase inhibitor (coefficient =1.7; OR: 6.0; P=0.003). None of the covariates were significant using multivariate analysis. Conclusion Older age, a higher pretreatment IOP, using multiple antiglaucoma medications especially topical carbonic anhydrase inhibitor, and higher refractive errors were associated with greater SLT success.