Background
The aim of this study was to compare the efficacy and safety of micropulse and continuous wave diode transscleral cyclophotocoagulation in refractory glaucoma.
Design
Randomized, ...comparative, exploratory study in a tertiary hospital setting.
Participants
Patients with refractory, end‐stage glaucoma.
Methods
Forty‐eight patients were randomized to either treatment. The intraocular pressure, visual acuity, number of medicines and repeat treatment were monitored for 18 months. Complications that include visual acuity decline, prolonged anterior chamber inflammation, phthisis bulbi, scleral thinning and ocular pain were noted.
Main Outcome Measure
Intraocular pressure between 6 and 21 mmHg and at least a 30% reduction with or without anti‐glaucoma medications after 18 months.
Results
A successful primary outcome was achieved in 75% of patients who underwent micropulse cyclophotocoagulation and 29% of patients who received continuous wave cyclophotocoagulation after 12 months (P < 0.01). At 18 months, successful outcome was 52% and 30% (P = 0.13), respectively. The mean intraocular pressure was reduced by 45% in both groups (P = 0.70) from a baseline of 36.5 mmHg and 35.0 mmHg (P = 0.50) after 17.5 ± 1.6 months (range 16–19) follow up. No significant difference in retreatment rates or number of intraocular pressure lowering medications was noted. The ocular complication rate was higher in continuous wave treated eyes (P = 0.01).
Conclusion
Diode transscleral cyclophotocoagulation in both micropulse and continuous modes was effective in lowering intraocular pressure. The micropulse mode provided a more consistent and predictable effect in lowering intraocular pressure with minimal ocular complications.
To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle ...closure when compared with gonioscopy in Asian subjects.
Prospective observational case series.
Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery.
Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions.
Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard.
Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 66.7% eyes) and by gonioscopy in 99 (49.5%) patients (152 44.4% eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval CI, 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard, specificity of AS-OCT in the dark was 55.4% (95% CI, 45.2-65.2) for detecting individuals with angle closure.
Anterior segment OCT is a rapid noncontact method of imaging angle structures. It is highly sensitive in detecting angle closure when compared with gonioscopy. More persons are found to have closed angles with AS-OCT than with gonioscopy.
Novel anterior segment optical coherence tomography (ASOCT) parameters associated with angle closure include anterior chamber area (ACA), anterior chamber volume (ACV), anterior chamber width (ACW), ...lens vault (LV), iris thickness (IT), iris area (I-area), and iris curvature (I-curv). We aimed to investigate changes in these parameters after laser peripheral iridotomy (LPI) in a cohort of primary angle-closure suspects (PACS).
Prospective observational study.
A total of 176 PACS aged ≥ 50 years who underwent LPI in 1 eye.
We analyzed ASOCT images (Visante, Carl Zeiss Meditec, Dublin, CA) from all subjects using customized software before and 1 week after LPI. Multivariate linear regression analysis was performed for predictors of percentage change in mean angle opening distance (AOD750).
Change in ASOCT parameters after LPI.
The mean age of participants was 63 ± 7.3 years. The majority of subjects were Chinese (95.5%) and women (76.7%). Mean angle width (modified Shaffer grade) changed from 0.68 ± 0.54 at baseline to 1.76±0.69 after LPI (P<0.001) with a corresponding increase in mean AOD500 (0.12 vs. 0.19 mm, P<0.001), trabecular iris surface area (TISA500, 0.06 vs. 0.08 mm(2), P<0.001), and angle recess area (ARA, 0.13 vs. 0.17 mm(2), P<0.001). Mean ACA (15.0 vs. 16.0 mm(2), P<0.001) and ACV (91.6 vs. 103.0 mm(3), P<0.001) increased significantly after LPI, but there was no change in ACW, anterior chamber depth (ACD), or LV. Mean I-curv was reduced (0.375 vs. 0.18 mm, P<0.001) after LPI, but there was no significant change in IT or I-area. After multivariate analysis, mean LV (β = 0.286, P = 0.001), mean IT at 2000 μm (IT2000, β = 0.172, P = 0.034), and intraocular pressure (β = 0.159, P = 0.042) at baseline were found to be associated with ΔAOD750.
This study confirms that LPI results in a significant increase in the angle width in PACS. The ACA and ACV increased after LPI, but there was no change in ACD, ACW, LV, IT, or I-area. The increase in ACA/ACV was mainly due to decreased I-curv after LPI.
To determine the incidence and baseline clinical and anterior segment optical coherence tomography (AS-OCT) predictors associated with residual angle closure as assessed by gonioscopy 1 year after ...laser peripheral iridotomy (LPI) in primary angle closure suspects (PACS).
Subanalysis of randomized controlled trial data.
AS-OCT images from 181 PACS subjects ≥50 years of age were analyzed using customized software before and 1 year after LPI. Other parameters assessed were intraocular pressure (IOP) and axial length (Axl). Residual angle closure was defined as the inability to see the posterior trabecular meshwork for at least 2 quadrants on gonioscopy after LPI. Multivariate regression analysis determined the baseline predictors of residual angle closure 1 year after LPI.
The mean age of participants was 62.4 (standard deviation 9.9) years. The majority were female (137, 75.7%) and Chinese (174, 96.1%). At 1 year post LPI, 148 (81.8%) subjects had gonioscopic residual angle closure. Univariate analysis showed that baseline Axl, anterior chamber area, anterior chamber volume, angle opening distance at 750 μm from the scleral spur, and angle recess area were smaller while baseline lens vault and iris curvature were larger in residual angle closure subjects (all P < .05). Multivariate analysis revealed that baseline iris volume (B = −0.08, P = .035) and baseline IOP (B = 0.23, P = .032) were predictors for residual angle closure.
One year after LPI, >80% of PACS had gonioscopic residual angle closure. Greater baseline iris volume and higher IOP at baseline are independent risk factors for residual gonioscopic angle closure.
In recent years, there has been a paradigm shift in glaucoma surgical procedures. Glaucoma drainage implant (GDI) surgeries are being performed much more commonly. Thus, it is important for surgeons ...to be cognisant of potential complications and their management. Exposure of a GDI is a well‐known complication, and prompt recognition and treatment are required to prevent endophthalmitis, a potentially blinding condition. In this review, we discuss the mechanisms and risk factors for GDI exposure, highlight important considerations for repair, and discuss repair techniques, with the aim of improving patient outcomes and minimising the risk of re‐exposure.
Cross-Examination for Angle-Closure Glaucoma Feature Detection Issac Niwas, Swamidoss; Weisi Lin; Chee Keong Kwoh ...
IEEE journal of biomedical and health informatics,
2016-Jan., 2016-Jan, 2016-1-00, 20160101, Letnik:
20, Številka:
1
Journal Article
Recenzirano
Effective feature selection plays a vital role in anterior segment imaging for determining the mechanism involved in angle-closure glaucoma (ACG) diagnosis. This research focuses on the use of ...redundant features for complex disease diagnosis such as ACG using anterior segment optical coherence tomography images. Both supervised minimum redundancy maximum relevance (MRMR) and unsupervised Laplacian score (L-score) feature selection algorithms have been cross-examined with different ACG mechanisms. An AdaBoost machine learning classifier is then used for classifying the five various classes of ACG mechanism such as iris roll, lens, pupil block, plateau iris, and no mechanism using both feature selection methods. The overall accuracy has shown that the usefulness of redundant features by L-score method in improved ACG diagnosis compared to minimum redundant features by MRMR method.
Background: To evaluate different mechanisms of primary angle closure and to quantify anterior chamber parameters in these mechanisms using anterior segment optical coherence tomography in an Asian ...population.
Design: Hospital‐based cross‐sectional observational study.
Participants: Forty‐eight consecutive patients with primary angle closure glaucoma.
Methods: Patients underwent complete ophthalmic examination and imaging of nasal‐temporal angles with anterior segment optical coherence tomography. Images were categorized into four primary angle closure mechanisms: pupil block, plateau iris configuration, Thick peripheral iris roll and exaggerated lens vault. Parameters computed: anterior chamber depth central, anterior chamber depth at 1000 µm and 2000 µm anterior to scleral spur, lens vault, anterior chamber area, angle opening distance, trabecular iris space area and iris thickness.
Main Outcome Measure: Anterior chamber parameters and primary angle closure mechanisms.
Results: Mean values of anterior chamber depths: central (P < 0.001), at 2000 µm (P < 0.001), 1000 µm (P < 0.001), lens vault (P < 0.001), anterior chamber area (P < 0.001), were significantly different among the four groups. Multivariate analysis showed anterior chamber depths: central, and anterior chamber depth at 2000 µm and anterior chamber area were higher in plateau iris and Thick peripheral iris roll and lower in exaggerated lens vault (P < 0.001) as compared to pupil block mechanism, lens vault was greater in exaggerated lens vault (P < 0.001) and lesser in plateau iris and Thick peripheral iris roll as compared to pupil block mechanism.
Conclusion: Anterior segment optical coherence tomography may be used for evaluation of underlying primary angle closure mechanism(s) in a patient and tailor the treatment accordingly.
To image trabeculectomy blebs using anterior segment optical coherence tomography (AS-OCT).
Prospective cross-sectional study.
Fifty-five patients who had previously undergone trabeculectomy surgery.
...All blebs were imaged with a prototype of the AS-OCT. Standardized color monophotographs of blebs were also obtained. Blebs were assessed for the following qualitative features: bleb height, thickness of the conjunctiva in the bleb wall, presence of cystic spaces within the bleb wall, apposition of the scleral flap to underlying sclera, and patency of the internal ostium.
For blebs with preoperative intraocular pressure (IOP) > 18 mmHg with or without ocular hypotensive medication, success was defined as last recorded IOP< or =18 mmHg without topical glaucoma medication. For blebs with preoperative IOP< or =18 mmHg with ocular hypotensive medication, success was defined last recorded IOP< or =18 mmHg with cessation of ocular hypotensive medication. For blebs with preoperative IOP< or =18 mmHg without ocular hypotensive medication, a 20% drop in IOP with no ocular hypotensive medication was accepted as success.
Seventy-eight blebs in eyes of 55 patients were imaged. There were 32 (58.2%) men and the mean age was 68.9+/-11.5 years. Fifty-seven (73.1%) blebs were classified as successful. Anterior segment optical coherence tomography identified the following bleb characteristics: total bleb height, bleb cavity, bleb wall thickness, tangential and radial dimensions, scleral flap thickness, and patency of the internal ostium. The majority of successful blebs displayed thickening of the bleb wall. Failed blebs were mostly low and were characterized by ostial occlusion, apposition of conjunctiva-episclera to sclera or apposition of the scleral flap to its bed. Thickening of the bleb wall was typically absent.
AS-OCT is a promising tool to image trabeculectomy blebs. It was able to demonstrate features of bleb morphology not visible with the slit lamp.
Highlights • We proposed a new method for automated classification of various angle closure disease mechanisms. • We directly extracted the compound image transformed features from the raw Anterior ...Segment optical coherence tomography (AS-OCT) images without any segmentation and parameter measurement. • An important contribution of this work: There is no need of anterior chamber area's segmentation. So, anterior chamber characteristics measurement is not required in this method.
Objective: To systematically review the efficacy and tolerability of 4 prostaglandin analogues (PGAs) as first-line monotherapies for intraocular pressure (IOP) lowering in adult patients with ...primary open-angle glaucoma or ocular hypertension. Data Sources: A literature search was performed in PubMed (1965-June 2013) and the Cochrane Library (1980-June 2013) using the search terms ocular hypertension, open-angle glaucoma, prostaglandin analogues, bimatoprost, latanoprost, tafluprost, and travoprost. Additional studies were searched from the reference lists of identified publications. Study Selection and Data Extraction: In all, 32 randomized controlled trials comparing between PGAs (bimatoprost 0.03%, latanoprost 0.005%, tafluprost 0.0015%, and travoprost 0.004%) or PGA with timolol were selected. Data Synthesis: A network meta-analysis was conducted. Using timolol as reference, the relative risks (RRs) of achieving treatment success, defined as the proportion of patients achieving at least 30% IOP reduction, with 95% CIs, were as follows: bimatoprost, 1.59 (1.28-1.98); latanoprost, 1.32 (1.00-1.74); travoprost, 1.33 (1.03-1.72); and tafluprost, 1.10 (0.85-1.42). The mean IOP reductions after 1 month were 1.98 (1.50-2.47), 1.01 (0.55-1.46), 1.08 (0.59-1.57), and 0.46 (−0.41 to 1.33) mm Hg, respectively, and the results were sustained at 3 months. Bimatoprost was associated with the highest risk of developing hyperemia, whereas latanoprost had the lowest risk, with RRs (95% CI) of 4.66 (3.49-6.23) and 2.30 (1.76-3.00), respectively. Conclusions: Bimatoprost achieved the highest efficacy in terms of IOP reduction, whereas latanoprost had the most favorable tolerability profile. This review serves to guide selection of the optimal PGA agent for individual patient care in clinical practice.