Doris W.F. Yick

Retrospective case series on the long-term visual and intraocular pressure outcomes of phacomorphic glaucoma

PurposeTo analyse the long-term visual acuity (VA) and intraocular pressure (IOP) outcomes in phacomorphic glaucoma.Patients and methodsA retrospective analysis of 100 consecutive, acute phacomorphic glaucoma cases from January 2000 to April 2009 was conducted at The Caritas Medical Centre in Hong Kong. All cases underwent cataract extraction after IOP control with medication and/or laser.ResultsDuring a 3.1±2.6-year follow-up, the mean visual improvement was 1.1±0.9 LogMAR units with improvements in 81.7% of cases. A shorter duration from symptoms to cataract extraction resulted in greater visual improvement (r2=0.1, P=0.001). In all, 80.5% of the cases had IOP⩽21 mm Hg without any glaucoma treatment; 19.5% required 1.6±0.7 glaucoma eye drops; and 3.7% required additional laser iridotomy or trabeculectomy for IOP control at 1.8±2.3 years. The vertical cup–disc ratio (VCDR) of the index eye was 0.6±0.3. Gonioscopy revealed an averaged Shaffer grading of 3.0±1.0 and 99±90 degrees of peripheral anterior synechiae (PAS). The Humphrey automated perimetry mean deviation was 5.2±2.7 and the pattern standard deviation was −15.9±10.ConclusionOver 80% of phacomorphic patients had long-term visual improvements and normalization of IOP after cataract extraction. A shorter attack seemed to offer better VA. Post-operatively, most have open angles with some degree of PAS formation, and glaucomatous optic neuropathy is evident from enlarged VCDRs and visual field defects. At least 2 years of follow-up is useful to detect a 20% glaucoma progression possibly requiring additional glaucoma treatments.

Intrableb triamcinolone acetonide injection after bleb-forming filtration surgery (trabeculectomy, phacotrabeculectomy, and trabeculectomy revision by needling): a pilot study

Intrableb triamcinolone acetonide injection after bleb-forming filtration surgery (trabeculectomy, phacotrabeculectomy, and trabeculectomy revision by needling): a pilot study

Retrospective analysis of the risk factors for developing phacomorphic glaucoma.

Aim: To determine the risk factors for developing phacomorphic glaucoma in eyes with mature cataracts. Materials and Methods: This is a case-control study comprising of 90 eyes with phacomorphic glaucoma and 90 age- and sex-matched control eyes with mature cataracts without phacomorphic glaucoma. Patients with pre-existing glaucoma, previous intraocular surgery and /or absence of documented axial lengths were excluded from this study. Binary logistic regression analysis of the variables, axial length and anterior chamber depth, was performed. Anterior chamber depth of the contralateral eye was used as a proxy measure of the pre-phacomorphic state in the eye with phacomorphic glaucoma as majority of them first presented to our center during the phacomorphic attack without prior measurements of the pre-phacomorphic ACD or lens thickness; therefore, their anterior chamber depth would not be representative of their pre-phacomorphic state. Axial length of 23.7 mm was selected as a cut-off for dichotomized logistic regression based on the local population mean from published demographic data. Results: The mean age was 73.1 ± 10.2 years. All phacomorphic and control eyes were ethnic Chinese. The mean presenting intraocular pressures were 49.5 ± 11.8 mmHg and 16.7 ± 1.7 mmHg in the phacomorphic and control eyes respectively (P< 0.0001), whilst the median Snellen best corrected visual acuity were light perception and hand movement in the phacomorphic and control eyes respectively. Eyes with phacomorphic glaucoma had shorter axial length of 23.1 ± 0.9 mm median when compared with that of control eyes, 23.7 ± 1.5 mm (P = 0.0006). Eyes with AL ≤ 23.7 mm were 4.3 times as likely to develop phacomorphic glaucoma when compared with AL > 23.7 mm (P = 0.003). Conclusion: Axial length less than ≤ 23.7 mm was a risk factor for developing phacomorphic glaucoma. Eyes with AL shorter than the population mean were 4.3 times as likely to develop phacomorphic glaucoma compared with eyes with longer than average AL. In an area where phacomorphic glaucoma is prevalent and medical resources are limited, patients with AL shorter than their population mean may be considered for earlier elective cataract extraction as a preventive measure.

Fornix‐based trabeculectomy using the ‘anchoring’ corneal suture technique

Aim: To assess the safety and efficacy of fornix‐based trabeculectomy with the ‘anchoring’ corneal suture technique in Chinese patients.

Microincision bimanual phacotrabeculectomy in eyes with coexisting glaucoma and cataract

PURPOSE: To report the technique and surgical outcomes of microincision bimanual phacotrabeculectomy in eyes with glaucoma and coexisting cataract. SETTING: Glaucoma Service, Hong Kong Eye Hospital, Hong Kong SAR, China METHODS: Microincision bimanual phacoemulsification with a sleeveless phaco needle and irrigating chopper was performed in combination with trabeculectomy. Phacoemulsification was performed through 2 small clear corneal wounds, sparing the trabeculectomy site from trauma. The intraocular lens (IOL) was then implanted through the trabeculectomy site, so no corneal wound larger than 1.5 mm was required for IOL implantation. RESULTS: The first 10 consecutive eyes of 10 patients who had combined phacotrabeculectomy by a microincision bimanual technique had significantly reduced intraocular pressure. There was a 10.5% reduction in the mean corneal endothelial cell count. There were no other complications up to 6 months after surgery. CONCLUSION: Microincision bimanual phacotrabeculectomy appeared to be an effective and safe option in patients with glaucoma and coexisting cataract.

Retinal nerve fiber layer thickness in myopic, emmetropic, and hyperopic children.

AbstractThe purpose of this study was to investigate the peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, emmetropic, and hyperopic children using optical coherence tomography.Two-hundred one right eyes of subjects aged 4 to 18 years were divided into 3 groups based on their postcycloplegic spherical equivalent: myopes (<−1.0 D), emmetropes (≥−1.0 to ⩽+1.0 D), and hyperopes (>+1.0 D). The RNFL was correlated with age, spherical equivalent, and axial length. The RNFL was compared between the 3 groups before and after age adjustment.The RNFL was thickest in the hyperopic group (107.2 ± 10.13 &mgr;m, n = 73), followed by the emmetropic group (102.5 ± 9.2 &mgr;m, n = 61), and then the myopic group (95.7 ± 10.3, n = 67) (all P < 0.0001). The myopic group (9.6 ± 3.9 years) was significantly older than the emmetropic (6.9 ± 2.7 years) and hyperopic (6.5 ± 1.9 years) groups (both P < 0.0001). When adjusted for age, myopes had a thinner RNFL than the other 2 groups (all P < 0.0001), but there was no RNFL thickness difference between the emmetropic and hyperopic groups (P > 0.05). A thinner RNFL was associated with an older age (r = −0.4, P < 0.0001), a more myopic spherical equivalent (r = 0.5, P < 0.0001), and a longer axial length (r = −0.4, P < 0.0001) on Pearson correlation analysis.The apparently thicker RNFL in hyperopic and emmetropic children was attributed to their younger age as compared with their myopic counterparts. When adjusted for age, only myopia was associated with a thinner RNFL, with emmetropic and hyperopic children having equal RNFL thicknesses. Advancing age, a more myopic spherical equivalent, and a longer axial length were associated with a thinner RNFL in children.

Cross-sectional study of the retinal nerve fiber layer thickness at 7 years after an acute episode of unilateral primary acute angle closure

Abstract The purpose of this article is to investigate the long-term retinal nerve fiber layer (RNFL) status and determinants of RNFL thinning after an episode of unilateral primary acute angle closure (AAC). This cross-sectional study analyzed the medical records of consecutive patients with a single episode of unilateral AAC from 1999 to 2009 in Hong Kong. The peripapillary RNFL thickness was correlated with age, gender, presenting intraocular pressure (IOP), time to laser iridotomy, time to cataract extraction, follow-up duration, as well as the last IOP, vertical cup-to-disc ratio (CDR), and vision. The fellow uninvolved eye was used as a proxy comparison of RNFL loss in the attack eye. In 40 eligible patients, the mean age was 68.3 ± 8.7 years with a male-to-female ratio of 1:7. The mean presenting IOP was 49.2 ± 14.0 mm Hg and the time from presentation to laser iridotomy was 6.7 ± 6.9 days. Forty percent of subjects received a cataract extraction at 3.2 ± 2.9 years after the attack. The last IOP, CDR, and LogMAR vision were 16.0 ± 3.8 mm Hg, 0.6 ± 0.2, and 0.6 ± 0.6 LogMAR units, respectively, at 7.9 ± 2.4 years. The RNFL thickness in the attack eye (69.2 ± 19.1 &mgr;m) was 25.2 ± 17.9% thinner than the fellow eye (93.0 ± 17.8 &mgr;m) at 7.5 ± 2.9 years post-AAC. Using univariate analysis, the last vertical CDR (odds ratio [OR] = 17.2, P = 0.049) and LogMAR visual acuity (VA) (OR = 6.6, P = 0.03) were the only significant predictors for RNFL thinning whereas none of the other covariates showed significant associations (P > 0.1). At 7.5 years following unilateral AAC, the RNFL thickness was 25% thinner than the fellow eye. CDR enlargement and poor VA were the only significant predictors for RNFL loss.

The Anterior Chamber Depth and Retinal Nerve Fiber Layer Thickness in Children

Purpose. To investigate the correlation of anterior chamber depth (ACD) with the peripapillary retinal nerve fiber layer (RNFL) thickness, age, axial length (AL), and spherical equivalent in children. Subjects. Consecutive subjects aged 4 to 18 were recruited. Visually disabling eye conditions were excluded. Only the right eye was included for analysis. The ACD was correlated with RNFL thickness, age, spherical equivalent, and AL for all subjects. Subjects were then divided into 3 groups based on their postcycloplegic spherical equivalent: myopes (<−1.0 D), emmetropes (≥−1.0 to ≤+1.0 D), and hyperopes (>+1.0 D). The ACD was compared among the 3 groups before and after age adjustment. Results. In 200 subjects (mean age 7.6 ± 3.3 years), a deeper ACD was correlated with thinner global RNFL (r = −0.2, r 2 = 0.06, P = 0.0007), older age (r = 0.4, r 2 = 0.1, P < 0.0001), myopic spherical equivalent (r = −0.3, r 2 = 0.09, P < 0.0001), and longer AL (r = 0.5, r 2 = 0.2, P < 0.0001). The ACD was deepest in myopes (3.5 ± 0.4 mm, n = 67), followed by emmetropes (3.4 ± 0.3, n = 60) and then hyperopes (3.3 ± 0.2, n = 73) (all P < 0.0001). After age adjustment, myopes had a deeper ACD than the other 2 groups (all P < 0.0001). Conclusions. In children, a deeper ACD was associated with thinner RNFL thickness, older age, more myopic spherical equivalent, and longer AL. Myopes had a deeper ACD than emmetropes and hyperopes.

Efficacy and Safety of Trabectome Surgery in Chinese Open-Angle Glaucoma.

AbstractTo investigate the clinical outcome of the Trabectome in Chinese open-angle glaucoma (OAG).This prospective case series recruited pseudophakic glaucoma subjects with open-angle configuration. Trabeculectomy ab interno was performed using the Trabectome to 120° of the trabecular meshwork. Intraocular pressure (IOP) and medications were recorded preoperatively and every 3 months postoperatively. Visual acuity was measured preoperatively and at 1 and 6 months postoperatively. One-way ANOVA with Tukey Multiple Comparison Test were used to measure the pre and postoperative parameters.In 19 eyes of 19 Chinese subjects, 26.3% were uveitic, 68.4% were primary open-angle glaucoma, and 5.3% had a history of chronic angle-closure glaucoma with open-angles after cataract extraction. The subjects’ mean age was 67.5 ± 14.4 years, with 4 females and 15 males. Two patients required secondary filtration procedure. At 6 months, the IOP reduced by 34.8% (24.4 ± 4.4 mm Hg to 15.9 ± 5.1 mm Hg, P < 0.0001). The number of types of antiglaucoma medications was reduced by 28.2% (3.9 ± 0.8–2.8 ± 1.6, P < 0.0001). The visual acuity was static at 1 and 6 months postoperatively (P = 0.4). There were no intraoperative complications. 26.3% of subjects had a transient IOP spike > 21 mm Hg, 1 had hyphema requiring washout, and 1 had reactivation of herpetic keratitis. The success rate at 6 months was 89.5%.Trabectome achieved a modest reduction in IOP and medications in the majority of pseudophakic Chinese OAG eyes.

MicroPulse Laser Trabeculoplasty for the Treatment of Open-Angle Glaucoma.

AbstractThe aim of the study was to investigate the safety and efficacy of using MLT in the treatment of open-angle glaucoma (OAG).This prospective cohort included subjects ≥18 years of age with OAG, defined as the open angle on gonioscopy with glaucomatous optic neuropathy evident from optical coherence tomography. Subjects with IOP < 21 mm Hg were classified as normal tension glaucoma and those with IOP ≥21 mm Hg were classified as primary open-angle glaucoma. Those with angle closure, secondary glaucoma, prior laser trabeculoplasty, use of systemic IOP-lowering medications, corneal pathologies, follow-up <6 months, recent intraocular surgery, or only 1 functional eye were excluded. A single session of unilateral MLT treatment was delivered using a 577 nm diode laser to 360° of the trabecular meshwork to reduce IOP or medication load. Medications were titrated up or down at 1 month after laser to achieve a 25% IOP reduction from presentation or an IOP <18 mm Hg, whichever was lower. The following were compared using the Repeated Measures ANOVA with Bonferronis Multiple Comparison Test: IOP (on presentation, pre-MLT, day 1, 1 week, 1 month, 3 months, and 6 months after MLT) and the number of medications (pre-MLT, 3 months, and 6 months after MLT). After 6 months, responders with initial success to MLT (IOP reduction ≥20% at 1 month) received treatment in the fellow eye.In 48 subjects with OAG, the mean number of MLT shots applied was 120.5 ± 2.0 shots using a mean energy of 1000 mW per shot. Only 7.5% had a mild, self-limiting anterior uveitis postlaser with no change in the Snellen visual acuity at 6 months (Ps > 0.5). The IOP and number of medications were significantly reduced at all time intervals following MLT compared to the pre-MLT level (Ps < 0.0001). At 6 months, the IOP was reduced by 19.5% in addition to a 21.4% reduction in medication compared to pretreatment levels. The MLT success rate was 72.9%. During the first 6 months only 2.1% required a repeated laser trabeculoplasty.MLT was effective in reducing IOP and medications in OAG with minimal postlaser inflammation and low failure rate at 6 months following laser.