Automatic retinal image analysis is emerging as an important screening tool for early detection of eye diseases. Glaucoma is one of the most common causes of blindness. The manual examination of ...optic disk (OD) is a standard procedure used for detecting glaucoma. In this paper, we present an automatic OD parameterization technique based on segmented OD and cup regions obtained from monocular retinal images. A novel OD segmentation method is proposed which integrates the local image information around each point of interest in multidimensional feature space to provide robustness against variations found in and around the OD region. We also propose a novel cup segmentation method which is based on anatomical evidence such as vessel bends at the cup boundary, considered relevant by glaucoma experts. Bends in a vessel are robustly detected using a region of support concept, which automatically selects the right scale for analysis. A multi-stage strategy is employed to derive a reliable subset of vessel bends called r-bends followed by a local spline fitting to derive the desired cup boundary. The method has been evaluated on 138 images comprising 33 normal and 105 glaucomatous images against three glaucoma experts. The obtained segmentation results show consistency in handling various geometric and photometric variations found across the dataset. The estimation error of the method for vertical cup-to-disk diameter ratio is 0.09/0.08 (mean/standard deviation) while for cup-to-disk area ratio it is 0.12/0.10. Overall, the obtained qualitative and quantitative results show effectiveness in both segmentation and subsequent OD parameterization for glaucoma assessment.
Background: The introduction of mitomycin C (MMC) as an adjunct to trabeculectomy was a major advance in the ability to improve the Intra ocular pressure lowering efficiency of the procedure. The ...time tested traditional way of administration of MMC is via a sponges soaked in it, duration and concentration varies depending on risk of failure. A subconjunctival injection of MMC instead of these sponges is recently being used as a promising alternative. Purpose: Here is the video demonstrating the 2 possible ways to prepare and apply MMC during a trabeculectomy surgery. Synopsis: Intraoperative injection of MMC in trabeculectomy has several advantages over conventional method ofsponge application. A large MMC treatment area produces more diffuse and elevated blebs. Large-area MMC application also seems to increase long-term success without increasing the complication rates in trabeculectomies. Direct and diffuse application of MMC by injection may promote less scarring and vascularization of the bleb. To achieve the same surface area of exposure with sponges, i.e.achieved with injection, the surgeon must use multiple sponges, all of which must be carefully collected thereafter. The injection method,therefore,eliminates the risk of retained sponges. Highlights: injection of MMC may be as safe and as effective as conventional sponge application of MMC with comparable estimated complete treatment success with relatively lower complication rates.
Video link: https://youtu.be/RLEbK4IeRtU
To report the intermediate-term outcomes of Aurolab aqueous drainage implant (AADI) surgery in paediatric eyes with refractory glaucoma.
Case records of patients below 18 years, who underwent AADI ...surgery between 2012 and 2015 with
2 years follow-up, were analysed. The intraocular pressure (IOP), visual acuity, number of antiglaucoma medications, complications and resurgery if any were recorded at baseline, day 1and then at months 1, 3, 6, 9, 12, 18, 24 and at the last visit. Failure was defined as IOP >18 mm Hg or not reduced by at least 30% below baseline, IOP ≤5 mm Hg on two consecutive follow-up visits after 3 months, reoperation for a complication or loss of light perception vision.
101 eyes of 101 patients were included with a mean age of 10.4±4.7 years at the time of surgery and a mean follow-up of 40.9±15.1 months. Glaucoma following cataract surgery was the most common type of glaucoma (n=31, 30%), followed by primary congenital glaucoma (n=29, 29%). The cumulative probability of failure was 15.8% (95% CI 10.1% to 24.5%) at 1 year, 22.7% (95% CI 15.7% to 32.2%) at 2 years, 42.5% (95% CI 32.6% to 53.9%) at 3 years and 62.1% (95% CI 49.5% to 74.8%) at the 4 years time point.
The AADI showed excellent success until 2 years after surgery in paediatric eyes after which failure rates increased. Further prospective studies with longer follow-up are required to evaluate the long-term success of the AADI for paediatric glaucomas.
To evaluate the demographic, clinical, and socioeconomic factors associated with variation in the quality of life (QOL) in caregivers of children with primary congenital glaucoma (PCG) in south ...India.
Cross-sectional survey.
Caregivers of children younger than 18 with diagnosed PCG were prospectively enrolled at Aravind Eye Hospital in Madurai and Coimbatore, India. Participants completed 2 questionnaires, the PHQ-9 (9-item Patient Health Questionnaire) and the CarCGQoL (Caregivers Congenital Glaucoma QOL Questionnaire). Clinical, demographic, and socioeconomic data were obtained for each child-caregiver dyad. Rasch-calibrated scores were calculated for patient-reported outcome measures. Spearman correlation and linear regression were used to analyze data to determine associations with caregiver QOL.
There were 70 caregivers (mean age 32.1, 77.1% female) of 70 children with PCG (mean age 7.7, 37.1% female) included in the study. In univariate and multivariable analyses, child's age (β = −0.04; 95% confidence interval, −0.08 to −0.01) and duration of disease (β = − 0.03; 95% confidence interval, −0.07 to −0.01) were the only factors associated with CarCGQoL. Survey items related to anger, self-confidence, irritability, appetite, and interest in leisure activities had the lowest scores. There was a negative correlation between CarCGQoL and PHQ-9 scores (r = −0.66, P < .01), indicating that worse caregiver QOL was significantly correlated with more depressive symptoms.
This study identified traits associated with QOL decline, as well as the QOL issues most likely to affect caregivers of children with PCG in south India. Findings from this study may be important for designing interventions to improve caregivers' QOL, thereby maximizing their ability to care for children with PCG.
Purpose: To compare the levels of cytokines and growth factor in aqueous humor of the patients with chronic primary angle closure glaucoma (PACG) and cataract.
Methods: Aqueous humor samples were ...collected from 19 chronic PACG patients and compared with 14 nonglaucomatous controls presenting for cataract surgery. The levels of 27 cytokines and growth factors were measured in the aqueous samples using multiplex bead immunoassay and compared across groups.
Results: Significantly higher levels of interleukin (IL)-8 (p < 0.001), eotaxin (p < 0.001), interferon gamma-induced protein (IP)-10 (p < 0.001) and macrophage inflammatory protein-1-beta (MIP-1β; p < 0.001) were observed in aqueous of chronic PACG patients compared to controls. In comparison to controls, significantly lower levels of IL-9 (p = 0.001), IL-17 (p < 0.001), tumor necrosis factor-alpha (TNF-α; p < 0.001), granulocyte-macrophage colony-stimulating factor (GM-CSF; p < 0.001), and IL-5 (p = 0.001) were observed in chronic PACG eyes. All other assayed cytokines-IL-1β, interleukin-1 receptor antagonist (IL-1rα), IL-6, IL-7, IL-10, IL-12, IL-13, IL-15, fibroblast growth factor-basic (FGF-basic), granulocyte colony-stimulating factor (G-CSF), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1-alpha (MIP-1α), and vascular endothelial growth factor (VEGF) -showed no significant difference between the groups.
Conclusions: These results suggest that the aqueous cytokine levels of chronic PACG eyes differ significantly from nonglaucomatous eyes. This is the first study reporting significantly increased levels of eotaxin, MIP-1β, and IP-10 and lower levels of TNF-α, IL-5, IL-9, IL-17, and GM-CSF in chronic PACG patients, suggesting a plausible role of these inflammatory cytokines in its pathogenesis.
Accurate segmentation of the cup region from retinal images is needed to derive relevant measurements for glaucoma assessment. A novel, depth discontinuity (in the retinal surface)-based approach to ...estimate the cup boundary is proposed in this paper. The proposed approach shifts focus from the cup region used by existing approaches to cup boundary. The given set of images, acquired sequentially, are related via a relative motion model and the depth discontinuity at the cup boundary is determined from cues such as motion boundary and partial occlusion. The information encoded by these cues is used to approximate the cup boundary with a set of best-fitting circles. The final boundary is found by considering points on these circles at different sectors using a confidence measure. Four different kinds of data sets ranging from synthetic to real image pairs, covering different multiview scenarios, have been used to evaluate the proposed method. The proposed method was found to yield an error reduction of 16% for cup-to-disk vertical diameter ratio (CDR) and 13% for cup-to-disk area ratio (CAR) estimation, over an existing monocular image-based cup segmentation method. The error reduction increased to 33% in CDR and 18% in CAR with the addition of a third view (image) which indicates the potential of the proposed approach.
A 6-year-old girl presented with blurred vision and was found to have elevated intraocular pressure (IOP) and glaucomatous optic disc damage in both eyes. She also displayed capillary malformations ...on the face (port-wine stain), upper back and all four limbs, angiomatosis in the brain and had hypertrophy of the left upper and lower limbs typical of overlapping Sturge-Weber syndrome and Klippel-Trenaunay syndromes. She was initially managed with IOP lowering topical medications but required trabeculectomy in the right eye followed by Ahmed valve implantation in both eyes. Despite multiple measures over a 7-year period, her IOP still remained uncontrolled with gradual progression of the glaucomatous damage. This case exhibits a very rare occurrence of overlapping syndromes reported only a handful of times in literature. Most cases with Sturge-Weber syndrome have ipsilateral glaucoma affecting the eye on the same side as the port-wine stain. This case presented with bilateral refractory childhood glaucomas, which is exceedingly rare.
Purpose: To evaluate the surgical outcomes of repeat trabeculectomy augmented with risk factor adjusted mitomycin C (MMC) exposure in eyes with previous failed trabeculectomy. Methods: Case records ...of 38 eyes of 37 patients with previous failed filter who underwent repeat trabeculectomy with MMC were reviewed retrospectively. Main outcome measures were best-corrected visual acuity (BCVA), intraocular pressure (IOP) reduction, requirement of anti-glaucoma medications, postoperative complications, and surgical success (defined as IOP of ≤21 mmHg and >5 mmHg along with 20% reduction from preoperative IOP with or without adjuvant medications) at 1-year postoperatively. Statistical analysis was done using the STATA 14.1 (Texas, USA). Results: Patient's mean age was 46.41 (±20.43) years and the mean preoperative IOP was 32.73 (±9.26) mmHg which reduced to 16.22 (±7.08) mmHg postoperatively at 12 months (P < 0.001). Mean number of anti-glaucoma medications reduced from 2.76 (±0.83) preoperatively to 1.89 (±0.95) postoperatively (P < 0.001). Surgical success was observed in 81.1% at 1 year (n = 30). Eyes that received MMC >3 min had a postoperative mean IOP of 12.50 (±3.23) mmHg compared to 23.08 (±7.19) mmHg with MMC <3 min (P < 0.001). Seven eyes (18.4%) developed postoperative complications, and all were seen in eyes that received MMC >3 min (P = 0.033). Conclusion: Repeat trabeculectomy with MMC, used in higher concentration and exposure time altered according to individual risk factor plays a crucial role in the success and hence it could be considered as a viable option before planning a tube surgery.
To describe and evaluate the performance of an automated CAD system for detection of glaucoma from color fundus photographs.
Color fundus photographs of 2252 eyes from 1126 subjects were collected ...from 2 centers: Aravind Eye Hospital, Madurai and Coimbatore, India. The images of 1926 eyes (963 subjects) were used to train an automated image analysis-based system, which was developed to provide a decision on a given fundus image. A total of 163 subjects were clinically examined by 2 ophthalmologists independently and their diagnostic decisions were recorded. The consensus decision was defined to be the clinical reference (gold standard). Fundus images of eyes with disagreement in diagnosis were excluded from the study. The fundus images of the remaining 314 eyes (157 subjects) were presented to 4 graders and their diagnostic decisions on the same were collected. The performance of the system was evaluated on the 314 images, using the reference standard. The sensitivity and specificity of the system and 4 independent graders were determined against the clinical reference standard.
The system achieved an area under receiver operating characteristic curve of 0.792 with a sensitivity of 0.716 and specificity of 0.717 at a selected threshold for the detection of glaucoma. The agreement with the clinical reference standard as determined by Cohen κ is 0.45 for the proposed system. This is comparable to that of the image-based decisions of 4 ophthalmologists.
An automated system was presented for glaucoma detection from color fundus photographs. The overall evaluation results indicated that the presented system was comparable in performance to glaucoma classification by a manual grader solely based on fundus image examination.
Aim/purpose
To report the incidence, risk factors, and magnitude of steroid response in individuals receiving topical 1% prednisolone acetate eye drops following phacoemulsification surgery
Materials ...and methods
Postoperative IOP of 1118 consecutive patients who had uneventful cataract surgery and used 1% topical prednisolone acetate were studied. Baseline ocular parameters like best-corrected visual acuity, IOP, and slit-lamp examination findings were noted preoperatively and at postoperative day 30. Incidence of postoperative intraocular pressure response to steroid was analyzed and graded as mild, moderate, or severe and risk factors studied.
Results
The mean age of our study cohort was 59.49 ± 7.25 years. The overall incidence of steroid response was 3.2%, (2.8% being moderate responders, and 0.4% high responders). Mean preoperative IOP was 14.67 ± 2.2 mm Hg in the study cohort (
n
= 1118). Mean postoperative IOP was 21.33 ± 7.97 mm Hg in the steroid responder (SR) and 14.66 ± 2.8 mm Hg in the non-responder (NR), with a statistically significant difference from the baseline IOP in the SR group (
p
< 0.001) and no difference in the NR. Univariate analysis revealed younger age and high axial length as risk factors but on multiple regression analysis, only younger age < 50 years was found to be a significant risk factor for steroid response.
Conclusion
The overall steroid response in this population post-cataract surgery was low with most being moderate responders. Younger age and higher axial length were identified as risk factors for steroid response, and hence this warrants the judicious use of steroids in such individuals.
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