Incidence of post vitrectomy endophthalmitis in India - A multicentric study by VRSI study Group.

INTRODUCTION: The incidence of post vitrectomy endophthalmitis (PVE) is reported to be between 0.02 and 0.84%. Resterilization of single use instruments is a common practice amidst developing countries to make it more affordable to the patients by reducing the cost of the surgery and also reduce the environmental hazard. The aim of our study is to evaluate the incidence of PVE amidst existing sterilization practices of reused instruments in multiple vitreoretinal centres in India. METHODOLOGY: Centres with an endophthalmitis tracking system were invited to participate in a survey. Twenty-five centres were sent a questionnaire via email. The questionnaire included details about the institution, number of vitrectomies performed in a year, sterilization practices followed pre-operatively, intraoperatively and postoperatively, incidence of endophthalmitis and instrument reuse policies. RESULTS: A total of 29 cases of endophthalmitis were reported out of the 47,612 vitrectomies performed across various centres. The mean incidence of endophthalmitis was 0.06%. There was no difference in the rates of endophthalmitis based on various pre-operative, intraoperative or postoperative prophylactic measures. Nearly 80% of the centres change most of the instruments after every case, while the rest reused. The mean number of times a cutter was being reused until discarded was 4.7. Nearly 76% followed a performance-based protocol, and the remaining 24% had a fixed protocol for the number of times an instrument can be reused before discarding it. CONCLUSION: PVE rates are not significantly different in India despite the multiuse of single use instruments. The purpose of this paper is not to suggest an alternate protocol but to creating one in the future with these results in mind, to rationalise the use of single use instruments, make VR surgery more affordable and also have a positive impact on the carbon footprint of consumables in surgery.

Plug it, fill it and forget it!

Background: Management of posterior scleral perforation is commonly done with cryotherapy/laser or scleral patch graft depending on the size of perforation. However, for large perforations, the availability of donor sclera is always an issue. To overcome this problem, we tried using absorbable gelatin sponge to plug the perforation as an alternative. Purpose: To evaluate the efficacy of gelatin foam as an alternative to scleral patch graft in cases with perforation of posterior sclera. Synopsis: Here we report the case of a 27-year-old male, who sustained penetrating injury to right eye with two metallic intraocular foreign bodies with visual acuity of hand movement close to face. Primary wound repair was done, followed by retrieval of the first piece of metallic foreign body that measured 11X3mm in size. The second foreign body visualized at posterior pole adjascent to the disc was removed using Machemar forceps and it measured 10X3 mmin size. Leakage of PFCL at the site confirmed a posterior scleral perforation. Cryotherapy was avoided due to its proximity to optic nerve head, and donor sclera was not readily available at that moment. We managed the case by plugging the defect with absorbable gelatin foam, followed by silicone oil injection into the vitreous cavity. Post operative outcome was good with restoration of anatomical integrity of the globe along with improvement in visual acuity upto 6/18. Highlights: Gelatin foam being absorbable and inciting less reaction aids in sealing the perforation and maintenance of globe contour with the advantage being readily available, cost-effective and it can be left in situ without the need for additional surgery for its removal. This would be of use in situations where the donor sclera is not readily available, and thus can be a potential alternative. However, further studies with larger sample size need to be done to evaluate and compare its effectiveness over donor scleral grafts. Online Video Link: https://youtu.be/fkardnkMQQo.

Ocular occlusions in two cases of COVID-19.

In late 2019, we saw the emergence of a new coronavirus, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which rapidly evolved into a global pandemic. We report two cases of ocular vascular occlusion related to coronavirus disease 2019 (COVID-19) disease. The first case is of choroidal artery occlusion, while the second case is of combined central retinal artery and vein occlusion (CRAO and CRVO). We performed a thorough literature search and to the best of our knowledge, neither any of the above said has been reported in COVID-19-positive patients.

Coats' disease - Prognostic factors for globe and vision salvage in children, a long-term experience.

PURPOSE: Coats' disease is associated with poor outcomes, and there are limited studies on long-term outcomes of Coats' disease. The purpose of our study is to identify various predictive factors to help in prognosticating the treatment outcomes in advanced Coats' disease in children. METHODS: This is a retrospective case series from a single tertiary eye care center of children (<18 years) diagnosed with coat's disease. Sixty-seven patients with Coat's disease were identified from the medical records from 2009 to 2020. Patients' demographic data, clinical presentation, stage, extent of involvement, detailed treatment history, clinical sequelae post-treatment (including complications and anatomical and functional outcomes) were noted. Binary logistic regression was performed to correlate the predictive factors for anatomical and functional improvement. RESULTS: Of the 67 patients, 51 eyes of 51 patients were included in the study. The male to female proportion was 2.2. Mean age at presentation was 4.98 ± 3.55 years (range: 2 months-15 years). Mean duration of follow-up was 31.53 ± 26.38 months. Overall, our globe salvage rate was 92.2%. We found that vitreoretinal fibrosis (P < 0.001), subretinal gliosis (P < 0.001), vitreous hemorrhage (P = 0.02), tractional or combined retinal detachment (P < 0.001), foveal scar (P < 0.006), and cataract (P < 0.001) to be important factors to affect the outcome. CONCLUSION: Advanced stage of presentation (stage 3B and above), diffuse involvement, cataract, vitreoretinal fibrosis (preretinal and subretinal), vitreous hemorrhage, tractional or combined retinal detachment, and anterior hyaloid proliferation are poor prognostic factors for globe salvage in advanced disease. Subretinal gliotic nodule or scar and lack of visual rehabilitation suggest poor functional outcomes.

Not-so-minimal for minimally invasive surgery.

Sub-macular hemorrhage poses a potential threat to vision if left untreated. The preferred surgical technique to clear sub-macular hemorrhage includes vitrectomy followed by retinotomy using a 41G needle with subsequent injection of recombinant tissue plasminogen activator (r-tPA) followed by air/SF6 injection into the sub-retinal space. A malleable nature, increased resistance, and the cost of the 41G needle limit its use. We evaluated the safety and efficacy of a 26G needle for retinotomy as a supplement for the 41G needle in a series of six subjects with sub-macular hemorrhage. A slight modification in the procedure was done by injecting air into the sub-retinal space prior to the r-tPA injection. We found that our technique of using the 26G needle for retinotomy is safe and effective due to its stable nature and self-sealing properties. An air injection prior to r-tPA allows for increased bioavailability of the drug by preventing efflux due to its tamponading effect.

Dexamethasone implant improves anatomic response to anti-VEGF therapy in treatment-resistant polypoidal choroidal vasculopathy.

BACKGROUND: A significant proportion of eyes with polypoidal choroidal vasculopathy (PCV) can be resistant to anti-vascular endothelial growth factor (VEGF) injections. We evaluated the efficacy of a combination of dexamethasone intravitreal implant (DXI) and anti-VEGF therapy in eyes resistant to anti-VEGF monotherapy. METHODS: In this retrospective study, patients with PCV resistant to anti-VEGF injections were additionally injected with a DXI along with an anti-VEGF agent. Best-corrected visual acuity (BCVA), slit-lamp examination, fundus evaluation, and optical coherence tomography (OCT) data were analyzed. Anatomical response on OCT was the primary outcome measure. Change in visual acuity and injection-free interval after DXI were evaluated as secondary outcome measures. RESULTS: Twelve eyes of 11 patients were included in the study. Mean age of patients at presentation was 64.7 ± 9.5 years (range, 49-78.8 years), and there were seven females (63.6%). Median number of anti-VEGF injections prior to DXI was 4 (interquartile range IQR, 3-7). Median follow-up duration after DXI was 32.2 months (IQR, 6.6-41.6 months). Median logMAR BCVA immediately prior to DXI was 0.41 (IQR, 0.30-0.88) and after injection was 0.40 (IQR, 0.30-1.05), which was not significantly different (p = 0.85). Median Central Retinal Thickness (CRT) after DXI was 305.5 µm (IQR, 249-409 µm), which was significantly (p = 0.003) lesser than pre-injection thickness of 547 µm (IQR, 431-771 µm). Median injection-free interval in these eyes after DXI was 5 months (IQR, 2.8-6.4 months). Kaplan-Meier estimates of first injection after DXI were 27.3% at 3 months, 67.3% at 6 months, and 89.1% at 12 months. CONCLUSIONS: Dexamethasone implant combined with anti-VEGF treatment can prolong the treatment-free interval in eyes with PCV resistant to anti-VEGF injection while maintaining visual acuity.

A questionnaire-based assessment of Safe Eye Examination (SEE) technique.

PURPOSE: This study aims to assess the novel and innovative method of Safe Eye Examination (SEE) technique using the model eye for the purpose of teaching, training, and resident examination. METHODS: A questionnaire-based study (Descriptive Data) with 53 participants, including ophthalmology residents, fellows in various subspecialties, and trainee optometrists was used. In our study, we used the Reti Eye model, but instead of the usual retina template sheet, we used prominent pathological fundus photographs loaded into the model eye. The study participants were asked to view prominent pathological fundus images printed on a matte finish paper. A circular image was cut and was placed in the Reti Eye model. The candidates were made to perform indirect ophthalmoscopy with a + 20D lens and to fill up a Google image assessment scale questionnaire with characteristics, including pixelation, sharpness, contrast, reflexes, blotchy appearance, and diagnostic confidence, which were then analyzed and depicted. Association between categorical variables was analyzed using Fisher exact test and Chi-square test. A P value of less than 0.05 was considered statistically significant. All data were analyzed with a statistical software package (SPSS, Version 16.0 for Windows). RESULTS: The number of positive responses (>90%) obtained for the pixelation, sharpness, contrast, reflexes, blotchy appearance, and diagnostic confidence of the image viewed were statistically more significant than the negative responses (P < 0.05). CONCLUSION: The SEE technique of using the model eye can be incorporated for teaching, training, and skill assessment in the examinations in these difficult times of COVID-19 (coronavirus disease 2019) pandemic.

Comparison of standard and "innovative wide-field" optical coherence tomography images in assessment of vitreoretinal interface in proliferative diabetic retinopathy: A pilot study.

Purpose: To compare the standard and "innovative wide-field" optical coherence tomography images in assessment of vitreoretinal interface in proliferative diabetic retinopathy. Methods: Fifty consecutive eyes of 25 patients with proliferative diabetic retinopathy underwent 12 × 12 mm radial swept source-optical coherence tomography (OCT) imaging using standard technique and innovative wide-field (+90D) technique. The image expansion ratio was calculated using Image J software. Results: Out of the 50 eyes, only in four eyes with +90 D were minimally misaligned or were having quality less than grade 2 as compared to standard OCT. The mean age group was 51 ± 4.5 years. The expansion ratio (scan length) increased by a factor of 1.65 ± 0.67 when obtained using +90 D technique. Conclusion: Innovative wide-field technique provides us with the widest of available OCT scans with the presently available machine and the software.

Idiopathic thrombocytopenic purpura and its fundus features in a patient with diabetes mellitus.

In this case report, we present a patient with thrombocytopenia secondary to idiopathic thrombocytopenic purpura (ITP), whose fundus appearance had features of diabetic retinopathy with macular edema. The macular edema did not respond to multiple intravitreal Anti-Vascular endothelial growth factor (Anti-VEGF), contrary to diabetic cystoid macular edema (CME). He was systemically investigated and was found to have ITP, and its management resulted in complete regression of the hemorrhages and CME.

Simultaneous mutually exclusive active tubercular posterior uveitis.

Ocular tuberculosis (TB) is a form of extra-pulmonary TB, which can involve almost any intraocular structure or ocular adnexa. Posterior uveitis, the commonest form of intraocular TB manifests as choroidal tubercles, choroidal tuberculoma, subretinal abscess, neuroretinitis, or serpiginous-like choroiditis. These forms of posterior tubercular lesions can be broadly classified into two groups based on their pathophysiology and morphology. One group of lesions is related to the direct invasion and reactivation of the bacilli in the choroidal tissue, whereas the other is a result of hypersensitivity reaction to the bacilli. Simultaneous bilateral active posterior uveitis with such varying morphology and pathophysiology in either eye of the same patient is an extremely rare presentation. We report a case with pulmonary TB on Anti-tubercular therapy (ATT), who presented to us with two mutually exclusive and distinctly different forms of tubercular posterior uveitis in either eye simultaneously. Both lesions were active at the time of presentation.

Diabetic Retinopathy Screening Using Smartphone-Based Fundus Imaging in India.

PURPOSE: Early detection and treatment can prevent irreversible blindness from diabetic retinopathy (DR), which is the leading cause of visual impairment among working-aged adults worldwide. Some 80% of affected persons live in low- and middle-income countries, yet lack of resources has largely prevented DR screening implementation in these world regions. Smartphone-based fundus imaging (SBFI) allows for low-cost mobile fundus examination using an adapter on a smartphone; however, key aspects such as image quality, diagnostic accuracy, and comparability of different approaches have not been systematically assessed to date. DESIGN: Evaluation of diagnostic technology. PARTICIPANTS: A total of 381 eyes of 193 patients with diabetes were recruited at outreach eye clinics in South India. METHODS: We compared 4 technically different approaches of SBFI (3 approaches based on direct and 1 approach based on indirect ophthalmoscopy) in terms of image quality and diagnostic accuracy for DR screening. MAIN OUTCOME MEASURES: Image quality (sharpness/focus, reflex artifacts, contrast, and illumination), field-of-view, examination time, and diagnostic accuracy for DR screening were analyzed against conventional fundus photography and clinical examination. RESULTS: Smartphone-based fundus imaging based on indirect ophthalmoscopy yielded the best image quality (P < 0.01), the largest field-of-view, and the longest examination time (111 vs. 68-86 seconds, P < 0.0001). Agreement with the reference standard (Cohen's kappa 0.868) and sensitivity/specificity to detect DR were highest for the indirect SBFI approach (0.79/0.99 for any DR and 1.0/1.0 for severe DR, 0.79/1.0 for diabetic maculopathy). CONCLUSIONS: Smartphone-based fundus imaging can meet DR screening requirements in an outreach setting; however, not all devices are suitable in terms of image quality and diagnostic accuracy. Smartphone-based fundus imaging might aid in alleviating the burden of DR screening in low- and middle-income countries, and these results will allow for a better selection of SBFI devices in field trials for DR screening.

Validation of Deep Convolutional Neural Network-based algorithm for detection of diabetic retinopathy - Artificial intelligence versus clinician for screening.

Purpose: Deep learning is a newer and advanced subfield in artificial intelligence (AI). The aim of our study is to validate a machine-based algorithm developed based on deep convolutional neural networks as a tool for screening to detect referable diabetic retinopathy (DR). Methods: An AI algorithm to detect DR was validated at our hospital using an internal dataset consisting of 1,533 macula-centered fundus images collected retrospectively and an external validation set using Methods to Evaluate Segmentation and Indexing Techniques in the field of Retinal Ophthalmology (MESSIDOR) dataset. Images were graded by two retina specialists as any DR, prompt referral (moderate nonproliferative diabetic retinopathy (NPDR) or above or presence of macular edema) and sight-threatening DR/STDR (severe NPDR or above) and compared with AI results. Sensitivity, specificity, and area under curve (AUC) for both internal and external validation sets for any DR detection, prompt referral, and STDR were calculated. Interobserver agreement using kappa value was calculated for both the sets and two out of three agreements for DR grading was considered as ground truth to compare with AI results. Results: In the internal validation set, the overall sensitivity and specificity was 99.7% and 98.5% for Any DR detection and 98.9% and 94.84%for Prompt referral respectively. The AUC was 0.991 and 0.969 for any DR detection and prompt referral respectively. The agreement between two observers was 99.5% and 99.2% for any DR detection and prompt referral with a kappa value of 0.94 and 0.96, respectively. In the external validation set (MESSIDOR 1), the overall sensitivity and specificity was 90.4% and 91.0% for any DR detection and 94.7% and 97.4% for prompt referral, respectively. The AUC was. 907 and. 960 for any DR detection and prompt referral, respectively. The agreement between two observers was 98.5% and 97.8% for any DR detection and prompt referral with a kappa value of 0.971 and 0.980, respectively. Conclusion: With increasing diabetic population and growing demand supply gap in trained resources, AI is the future for early identification of DR and reducing blindness. This can revolutionize telescreening in ophthalmology, especially where people do not have access to specialized health care.