Nafees Baig

Phacoemulsification versus Trabeculectomy in Medically Uncontrolled Chronic Angle-Closure Glaucoma without Cataract

OBJECTIVE To compare phacoemulsification versus trabeculectomy with adjunctive mitomycin C in medically uncontrolled chronic angle-closure glaucoma (CACG) without cataract. DESIGN Prospective, randomized clinical trial. PARTICIPANTS Fifty medically uncontrolled CACG eyes without cataract of 50 patients. INTERVENTION Patients were randomized into undergoing either phacoemulsification or trabeculectomy with adjunctive mitomycin C. After surgery, patients were followed up every 3 months for 2 years. MAIN OUTCOME MEASURES Intraocular pressure (IOP) and requirement for glaucoma drugs. RESULTS Twenty-six CACG eyes were randomized to receive phacoemulsification, and 24 eyes underwent trabeculectomy with mitomycin C. Phacoemulsification and trabeculectomy resulted in significant and comparable IOP reduction at 24 months after surgery (reduction of 8.4 mmHg or 34% for phacoemulsification vs. 8.9 mmHg or 36% for trabeculectomy; P=0.76). Over first 24 months, trabeculectomy-treated eyes required on average 1.1 fewer drugs than phacoemulsification-treated eyes (P<0.001). However, trabeculectomy was associated with significantly more surgical complications than phacoemulsification (46% vs. 4%; P=0.001). Eight (33%) of 24 trabeculectomy eyes demonstrated cataract during follow-up. CONCLUSIONS Both phacoemulsification and trabeculectomy are effective in reducing IOP in medically uncontrolled CACG eyes without cataract. Trabeculectomy is more effective than phacoemulsification in reducing dependence on glaucoma drugs, but is associated with more complications. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Intraocular pressure profiles during femtosecond laser-assisted cataract surgery.

Purpose To document the intraocular pressure (IOP) profiles during femtosecond laser–assisted cataract surgery. Setting Refractive cataract surgery center. Design Prospective case series. Methods Intraocular pressure was measured using a handheld portable applanation tonometer (Tono‐Pen Avia) during femtosecond laser–assisted cataract surgery using the Victus platform. Results Forty‐one eyes of 35 patients were recruited. The mean age of the patients was 70.5 years ± 8.2 (SD) (range 51 to 85 years). The mean IOP before, during, and after suction was 17.2 ± 3.2 mm Hg (range 10 to 23 mm Hg), 42.1 ± 10.8 mm Hg (range 20 to 55 mm Hg), and 13.8 ± 3.4 mm Hg (range 9 to 25 mm Hg), respectively. The mean difference between IOP before and during suction was 25.0 ± 11.3 mm Hg (range 5 to 43 mm Hg) (P<.01, Wilcoxon signed‐rank test). The mean difference between IOP during and after suction was −28.7 ± 10.8 mm Hg (range −45 to −10 mm Hg) (P<.01, Wilcoxon signed‐rank test). The mean suction duration was 216 ± 15 seconds (range 180 to 245 seconds). Conclusions The increase in IOP during the suction phase of femtosecond laser–assisted cataract surgery was statistically significant compared with the baseline IOP. Caution should be taken in patients with ocular conditions that are vulnerable to IOP fluctuation. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Circadian Intraocular Pressure Fluctuation and Disease Progression in Primary Angle Closure Glaucoma.

PURPOSE To document the continuous circadian intraocular pressure (IOP) fluctuation using a contact lens sensor during normal daily activities, and to study the relationship between IOP fluctuation and disease progression in primary angle closure glaucoma (PACG) eyes. METHODS Circadian IOP fluctuations were recorded by Sensimed Triggerfish sensors in 25 PACG eyes. The sensor output signals were smoothed using B-spline smoothing transform and described by functional data analysis. Glaucoma progression was documented with serial changes in mean deviation (MD) and visual field index (VFI) in Humphrey automated perimetry and retinal nerve fiber layer (RNFL) thickness. The signals were compared between the progressive and stable groups by permutation tests on functional t-statistic. RESULTS Statistically significant differences were found from 2200 to 2300 and from 0700 to 0800 in gradients of the IOP fluctuation curve, as well as from 2300 to 2400 and 0800 to 0900 in curvatures of the IOP fluctuation curves, between the progressive MD and stable MD groups (P < 0.05). Significant gradient differences were also found from 1500 to 1600 and 0600 to 0800 between the progressive VFI and stable VFI groups, and from 2400 to 0100 and 0200 to 0300 between the progressive RNFL and stable RNFL groups (P < 0.05). CONCLUSIONS Significant differences in circadian IOP fluctuation between progressive and stable PACG eyes were identified. Large IOP fluctuations may be associated with disease progression in PACG eyes.

Topiramate and asymptomatic ocular angle narrowing: a prospective pilot study

PurposeTo investigate whether subclinical ciliochoroidal effusion and resulting asymptomatic angle narrowing occurs in patients taking topiramate, by ultrasound biomicroscopy (UBM).MethodsChinese patients aged 18–75 years for whom topiramate was indicated were recruited. Examinations including UBM were performed before and 4 weeks after commencement of topiramate.ResultsIn this pilot of 20 eyes of 20 patients, there were no statistically significant changes in the angle parameters noted on gonioscopy or UBM, including anterior chamber depth, angle-opening distance at 500 μm, trabecular ciliary process distance, trabecular-iris angle, and scleral thickness.ConclusionShort-term use of topiramate does not induce asymptomatic angle narrowing.

Pressure–cornea–vascular index (PCVI) for predicting disease progression in normal tension glaucoma

Background It has been shown that the pressure-to-cornea index (PCI), which estimates the relative effects of intraocular pressure (IOP) and central corneal thickness (CCT), may differentiate between glaucoma and non-glaucoma states. The authors investigated the utility of the pressure–cornea–vascular index (PCVI) in predicting field-progression in patients with normal tension glaucoma (NTG). Methods PCVI was constructed from PCI (maximum IOP/CCT3) extended with risk factors identified as associated with field-progression in a prospective NTG cohort. Receiver operator characteristics and area under the curve (AUC) of a range of constructs were calculated to arrive at an optimal PCVI. Results 415 eyes from 415 NTG subjects (184 field-progressed and 231 field-stable) with 3 years of follow-up were analysed. The construct PCVI=(maximum pretreatment office IOP × age at presentation × vertical cup-to-disc ratio at presentation × (1.5 if presence of systemic hypertension; 2.5 if presence of disc haemorrhage; 3.5 if presence of both; 1.0 if none))/(CCT3×100) (CCT in mm) gave the highest AUC at 0.71 (95% CI 0.66 to 0.76, p<0.001). The mean PCVI were 113.1±76.8 and 69.7±39.7 for progressed and stable NTG groups, respectively (p<0.001). Conclusion PCVI may be useful for predicting progression in NTG with a satisfactory AUC comparable to established scoring systems in neurovascular medicine. Validation of PCVI in other NTG cohorts, preferably of different ethnicity, is necessary. Trial registration number NCT00321386.

Agreement of patient-measured intraocular pressure using rebound tonometry with Goldmann applanation tonometry (GAT) in glaucoma patients

This study aims to determine the agreement of patient-measured intraocular pressure (IOP) using rebound tonometry with ophthalmologist-measured IOP using Goldmann applanation tonometry (GAT). Fifty-three glaucoma patients used rebound tonometry (Icare ONE, Icare Finland Oy., Finland) to measure their own IOP in ambient environments for 1 week, 5 times per day. Clinic IOP measurements were performed by ophthalmologists using GAT and by patients using rebound tonometry on examination days 1, 4 and 7 of the same week. The agreement between the two tonometries was evaluated by modified Bland-Altman plots and intra-class correlation coefficient (ICC) was determined. Differences in ICCs of them among the three examination days were evaluated by bootstrap resampling analysis. Respective within-measurement ICC of GAT and rebound tonometry were 0.98 and 0.94 on Day 1, 0.98 and 0.93 on Day 4, and 0.96 and 0.92 on Day 7. In a modified Bland-Altman plot, the mean difference ±1 standard deviation (SD) between the two tonometries was 0.15 ± 0.65 mmHg (p = 0.682). Between-measurement ICC were 0.66, 0.76 and 0.73 on the 3 examination days. There was no significant difference among ICCs. In conclusion, patient-measured IOP using rebound tonometry and ophthalmologist-measured IOP using GAT demonstrate good agreement.

Managing Primary Angle Closure Glaucoma – The Role of Lens Extraction in this Era

Trabeculectomy has been the gold standard in reducing intraocular pressure (IOP) in glaucoma patients, no matter it is angle closure or open angle glaucoma. However in primary angle closure glaucoma, no matter the lens is cataractous or not, it is likely to be pathological, this thicker than usual lens, with or without a more anterior position, is often regarded as a strong contributing factor to angle closure. Lens extraction, no matter it is cataractous or clear, can theoretically eliminate this anatomical predisposing factor of angle closure, and thus IOP can be reduced. Based on recent results of a number of clinical trials, lens extraction alone or in combination with other IOP-lowering surgeries, may therefore play a more important role in the treating primary angle closure glaucoma. In cases when greater IOP-lowering effect is needed or if drug dependency has to be minimized, combined procedures, such as phacotrabeculectomy, can be considered, but the surgical risk can be higher than lens extraction alone.

Ultrasound evaluation of glaucoma drainage devices in children.

This study evaluated B-scan ultrasound as a technique for assessing glaucoma drainage device (GDD) patency/function in refractory pediatric glaucoma. We retrospectively evaluated 70 eyes of 52 patients after Ahmed (n = 40 eyes), Baerveldt (n = 27 eyes) and Molteno (n = 5 eyes) GDD implantation; 2 eyes each had 2 GDDs. Median age was 6.5 years. Glaucoma diagnoses included primary congenital glaucoma (n = 19) and secondary glaucoma associated with aphakia (n = 16), aniridia (n = 5), Peters anomaly (n = 3), uveitis (n = 2), and other conditions (n = 7). B-scan ultrasound evaluation proved helpful to clinical assessment when the GDD tube was not seen because of opaque corneas (n = 20 eyes), the bleb was not visualized (n = 21 eyes), or IOP was elevated (n = 28 eyes). Ultrasound findings suggesting a nonpatent or malfunctioning GDD were further confirmed by subsequent intraoperative bleb needling (n = 2 eyes) and GDD revision (n = 7 eyes). B-scan ultrasound evaluation can serve as a useful adjunct in evaluating GDD patency/function in selected eyes with refractory pediatric glaucoma and may aid in clinical management.

Comparison of self-measured diurnal intraocular pressure profiles using rebound tonometry between primary angle closure glaucoma and primary open angle glaucoma patients.

Purpose To document the diurnal intraocular pressure (IOP) profile with rebound tonometry performed by primary glaucoma patients in non-clinic environment. Patients and methods Fifty-three medically-treated eyes of 31 primary angle closure glaucoma (PACG) and 22 primary open angle glaucoma (POAG) patients with no previous eye surgery were recruited. Diurnal IOP was measured 5 times per day at four-hourly intervals from 08:00 to 24:00 for 1 week in patients’ study eye using rebound tonometry in a non-clinic environment. The diurnal IOP profiles were compared between PACG and POAG eyes. Results For both PACG and POAG eyes, mean patient-measured IOP was highest in the morning, gradually decreased over the course of a day, and was lowest by midnight (p < 0.001). The diurnal IOP fluctuation ± 1 standard deviation (SD), as documented by SD in daily IOP values, was lower in PACG group (1.6 ± 1.1 mmHg) than in POAG group (2.0 ± 1.2 mmHg; p = 0.049). The mean trough IOP ± 1 SD was higher in PACG group (12.9 ± 2.8 mmHg), compared to POAG group (11.5 ± 3.8 mmHg; p = 0.041). The mean IOP level at midnight ± 1 SD in PACG group (14.0 ± 3.2 mmHg) was higher than that in POAG group (12.1 ± 3.7 mmHg; p = 0.013). Conclusions IOP in primary glaucoma patients was highest in the morning, and decreased over the course of a day in non-clinic environment. Treated diurnal IOP fluctuation seemed to be greater in POAG than PACG eyes.

Lens extraction: where does it stand in the primary angle closure glaucoma management algorithm?

Cataractous or not, the lens in primary angle closure glaucoma (PACG) eyes is likely to be pathologically too thick and anteriorly positioned, and is one important contributing factor to angle closure. Extraction of the lens reverses the anatomical predisposition to angle closure and also significantly improves IOP control in PACG. Based on emerging evidence from recent clinical trials, lens extraction may play an important role in the surgical management of PACG, whether alone or in combination with other IOP-lowering interventions. Combined procedures such as phaco-trabeculectomy may be considered if greater IOP-lowering is desirable or if drug dependency must be minimized, but the associated complication risk is higher.