Statistical analysis plan for the phaco TIp position during clear corneal Phacoemulsification Surgery (TIPS) randomized controlled trial.

BACKGROUND: Cornea is the most important refractive media in the eye, and damage to the corneal endothelium is one of the most common causes of poor visual outcome following cataract surgery, particularly in those with predisposing factors. The role of phaco tip position during phacoemulsification on corneal endothelial damage is ambiguous, and there is no consensus regarding the most cornea-friendly phaco tip position (bevel-up or bevel-down). The objective of the trial is to compare the effect of phaco tip position (bevel-up vs. bevel-down) during phacoemulsification using direct chop technique on corneal endothelial cell count. METHODS AND DESIGN: TIPS is a randomised, multicentre, parallel-group, triple-masked (participant, outcome assessor, and statistician) trial with 1:1 allocation ratio. A total of 480 eligible participants, aged > 18 years with immature cataract, will be randomly allocated into bevel-up and bevel-down groups at two centres. Randomisation will be stratified according to the cataract grade. The primary outcome is postoperative endothelial cell count at 1 month. Secondary outcomes are central corneal thickness on postoperative days 1, 15, and 30 and difference in intraoperative complications. CONCLUSION: In this paper, we describe the detailed statistical analysis plan (SAP) for the TIPS trial, which was prepared prior to database lock. The SAP includes details of planned analyses and unpopulated tables, which will be reported in the publications. We plan to lock the database in July 2023 and publish the results later in the same year. SAP Version 0.1 (dated: 28 April 2023) Protocol version:2.0 TRIAL REGISTRATION: Clinical Trial Registry of India CTRI/2019/02/017464. Registered on 5 February 2019; https://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=29764&EncHid=&userName=2019/02/017464.

Can ultrasonic biometric indices with optimal cut-offs be a potential screening tool for primary angle closure disease? A case-control study.

BACKGROUND/OBJECTIVES: Despite a significant disease burden and potential to cause blindness, primary angle closure disease (PACD) does not have a population-based screening programme. Biometric indices using ultrasound A-scan is a potential tool for glaucoma case-detection. Given that genetic and environmental factors influence these parameters and paucity of data on their discrimination thresholds in Indian populace, we conducted a matched case-control study to determine the biometric indices and their discrimination thresholds associated with PACD. METHODS: We studied 172 eyes of 86 participants (43 cases; 43 controls). We compared the following biometric parameters of cases (PACD, occludable angle ≥180° ± raised intraocular pressure) with age and gender-matched controls (1:1): Anterior chamber depth (ACD), lens thickness (LT), axial length (AXL), lens position (LP), relative lens position (RLP), lens axial factor (LAF), simple crowding value (Cs), ACD/AXL). We performed conditional logistic regression (to identify factors associated with PACD) and Receiver operating characteristic (ROC) analysis (to determine discrimination thresholds). RESULTS: Reduced ACD (Adj OR 0.01; 95% CI: 0.0003-0.15, p < 0.001) and increased LT (Adj OR 10.3; 95% CI:2.42-43.93, p < 0.001) were associated with PACD. On ROC analysis, ACD, Cs, and ACD/AXL had optimum sensitivity/specificity at ≤3.015, ≥0.056 and ≤0.1303, respectively. ACD (88.4%) and Cs (94.2%) had highest sensitivity and specificity, respectively. CONCLUSION: Ultrasonic biometric parameters differed significantly between PACD and controls. ACD and Cs (at discrimination thresholds of ≤3.015 mm and ≥ 0.056, respectively) using ultrasound A-scan could be a potential tool for PACD case-detection that requires evaluation of its diagnostic yield and cost-effectiveness.

Factors associated with good near vision after cataract surgery with monofocal intraocular lens implantation at a tertiary eye hospital in southern India.

PURPOSE: Although multifocal intraocular lenses (IOLs) are effective methods of dealing with surgical presbyopia, there are associated limitations (cost, technique, and patient-reported symptoms). Given their scalability challenge (due to economic factors), it is imperative to explore alternative low-cost and sustainable solutions to achieve good near vision postcataract surgery. This study aimed to determine the proportion of and the factors associated with good near vision in patients following cataract surgery with monofocal IOL implantation. METHODS: We conducted a hospital-based cross-sectional study at a tertiary eye hospital in southern India from September 2019 to January 2020. Inclusion criteria: Uncomplicated postcataract surgery cases with monofocal IOL at least 30 days ago. Exclusion criteria: patients with any ocular condition (other than refractive errors) that could decrease the vision with best-corrected distance visual acuity < 0.18 Logarithm of the Minimum Angle of Resolution (LogMAR) units. Data collection: we assessed near vision (at 40 cm distance by using near vision card with Early Treatment of Diabetic Retinopathy Study format), distance visual acuity (uncorrected and best-corrected), refractive error (amount and type), type of astigmatism, pupil size, axial length, and contrast sensitivity. We considered a near vision of 0.2 LogMAR units or better as good near vision. RESULTS: Of the 82 patients (82 eyes), 71 (86.59%) had good near vision. Multiple logistic regression analysis found found that the presence of myopia or myopic astigmatism was significantly associated with good near vision (adjusted odds ratio: 72.63; 95% confidence interval: 1.02-5193.5, p = 0.049). CONCLUSION: About eight of every ten participants had good near vision postcataract surgery with monofocal IOL implantation. Myopia/myopic astigmatism was associated with good near vision.

Ergonomic practices and musculoskeletal disorders among ophthalmologists in India: An online appraisal.

INTRODUCTION: Ergonomics in ophthalmology is neither taught during professional training nor does it readily receive consideration or priority in clinical practice. Owing to a high prevalence of musculoskeletal disorders among ophthalmologists, ergonomic awareness, and practices are vital in averting this modern epidemic. OBJECTIVE: To assess the ergonomic practices and prevalence of self-reported musculoskeletal disorders among ophthalmologists in India. METHOD: An online survey was conducted among ophthalmologists who were registered with the All India Ophthalmological Society of India using a pre-tested and validated questionnaire. RESULTS: The prevalence of self-reported musculoskeletal disorder in the 377 participants was 75.3% (284; 95% confidence interval: 70.6-79.5). Low back pain (149, 52.9%) was the most commonly reported symptom. Musculoskeletal disorder-attributed productivity loss was reported by 58.45% (166) of the respondents. Musculoskeletal disorder was most frequently associated with less than 10 years of work experience (odds ratio: 1.2; 95% confidence interval: 1.1-1.3, p = 0.01) and lack of good clinic (odds ratio: 1.7; 95% confidence interval: 1.1-2.7, p = 0.03) and operation room ergonomic practices (odds ratio: 1.8; 95% confidence interval: 1.1-2.9, p = 0.03). Only 27.9% (105) of the respondents had accessed information related to ergonomics in ophthalmic practice. CONCLUSION: The self-reported musculoskeletal disorder among ophthalmologists in India is quite high and significant enough to cause some degree of productivity loss. It is thus imperative to emphasize the implementation of good ergonomic practices, especially among relatively young ophthalmologists.

Does the phaco TIp position during clear corneal Phacoemulsification Surgery adversely affect corneal endothelium? TIPS study protocol for a randomised, triple-masked, parallel-group trial of bevel-up versus bevel-down phacoemulsification.

Introduction: Globally, at least 30 million cataract surgeries are required annually to prevent cataract-related blindness. Corneal endothelial decompensation is one of the most common causes of poor visual outcome following cataract surgery, particularly in those with predisposing factors. The increasing ageing population and reduced visual impairment threshold for cataract surgery have resulted in rising cataract surgical rates and hence, an increase in corneal endothelial decompensation is expected. The role of phaco tip position on corneal endothelial damage is ambiguous. Previous studies have reported contradictory results and were also underpowered to detect a significant difference due to small sample sizes. With no consensus regarding the most cornea-friendly phaco tip position (bevel-up versus bevel-down) during phacoemulsification, we propose a randomised clinical trial with a robust design using direct chop phaco-technique. Objective: To compare the effect of phaco tip position (bevel-up vs. bevel-down) on corneal endothelial cell count during phacoemulsification. Methods: A randomised, multicentre, parallel-group, triple-masked (participant, outcome assessor, and statistician) trial with 1:1 allocation ratio is proposed. By adopting stratified randomisation (according to cataract grade), we will randomly allocate 480 patients aged >18 years with immature cataract into bevel-up and bevel-down groups at two centres. History of significant ocular trauma, previous intraocular surgery, shallow anterior chamber, low endothelial cell count, pseudoexfoliation syndrome, intraocular inflammation, and corneal endothelial dystrophy are the key exclusion criteria. The primary outcome is postoperative endothelial cell count at one month. Secondary outcomes are central corneal thickness on postoperative days 1, 15, and 30, and intraoperative complications. Trial registration: Clinical Trial Registry of India CTRI/2019/02/017464 (05/02/2019).

Occupational exposure to unburnt tobacco and potential risk of toxic optic neuropathy: A cross-sectional study among beedi rollers in selected rural areas of coastal Karnataka, India.

BACKGROUND: Beedi also known as poor man's cigarette is manufactured in almost all major states of India. Beedi workers are exposed to various health risks. There is an increased risk of systemic absorption of tobacco through skin and mucous membrane. The optic nerve is susceptible to damage from several toxic substances including tobacco. This group of disorders is known as toxic optic neuropathy (TON). The association of TON with occupational exposure to unburnt tobacco in beedi rollers has not been explored. OBJECTIVES: Among the beedi rollers in Mangaluru and Bantwal talukas of Dakshina Kannada District, Karnataka, India: to assess the magnitude of potential TON utilizing colour vision and contrast sensitivity as screening tools and to identify the demographic, biological and occupational factors associated with potential TON. METHODS: A community-based cross-sectional study was conducted from April-Sept 2016 in Mangaluru and Bantwal talukas, of Dakshina Kannada district, Karnataka. Beedi rollers from twelve villages (six from each taluka) were included. In each of the selected villages, the investigators identified beedi collection centres and all the eligible beedi rollers were included in the study till the required number of beedi rollers for that village was achieved. Participants were screened at the study site for visual acuity, colour vision and contrast sensitivity and those with abnormal colour and contrast sensitivity in the presence of good visual acuity were considered to have potential TON. RESULTS: A total of 377 beedi rollers were approached; of which 365 consented to take part in the study (response rate: 96.81%). Women constituted the majority of the participants (n = 338, 92.6%). Based on the screening criteria, the prevalence of potential TON was 17.5% (n = 64, 95% CI: 13.5-21.9). On multiple logistic regression analysis, duration of beedi rolling (Adj OR: 1.061; 95% CI 1.015-1.109, p = 0.009), advancing age (Adj OR: 1.096; 95% CI 1.058-1.136, p<0.001) and presence of diabetes (Adj OR: 6.315; 95% CI 1.4572-27.376, p = 0.014) were independent correlates of potential TON. CONCLUSION: In the present study, almost one out of six beedi rollers displayed clinical signs of potential TON. Increased duration of beedi rolling, advancing age and presence of diabetes were the independent correlates of potential TON. However, with this cross-sectional study it is not possible to conclude if these factors play a role individually or collectively or are a serendipitous association, for which large scale analytical studies are required.

Central corneal thickness changes in bevel-up versus bevel-down phacoemulsification cataract surgery: study protocol for a randomised, triple-blind, parallel group trial.

INTRODUCTION: Corneal endothelial damage following phacoemulsification is still one of the major concerns of modern day cataract surgery. Although many techniques have been proposed, the risks of posterior capsular rupture and corneal endothelium damage persist. In theory, damage to the corneal endothelium is minimised by delivering the lowest phaco energy only in the direction necessary to emulsify the lens nucleus. Hence, it is believed that the bevel of the needle should be turned towards the nucleus or the nuclear fragment (ie, bevel-down. However, there is a difference of opinion among ophthalmologists with reference to the phaco tip's position (bevel-up vs bevel-down) during phacoemulsification. This subject has not been extensively studied earlier. METHODS AND ANALYSIS: This is a prospective, triple-blinded (trial participant, outcome assessor and the data analyst), randomised controlled trial with 2 parallel groups and with an allocation ratio of 1:1. It will be conducted in a tertiary care hospital, Mangaluru, India. The objective is to compare the postoperative central corneal thickness changes between the bevel-up and bevel-down techniques of phacoemulsification. Patients aged >18 years with immature cataract undergoing phacoemulsification will be selected for the study. The important exclusion criteria are the history of previous significant ocular trauma or intraocular surgery, corneal pathology, pseudoexfoliation syndrome, intraocular inflammation, a preoperative fully dilated pupil <6 mm, anterior chamber depth <2.5 mm and nuclear sclerosis grade >4. After randomisation, patients will undergo phacoemulsification surgery either by a bevel-up or bevel-down procedure. With an estimated power of 80%, the calculated sample size is 55 patients in each group. The recruitment will start from April 2016. ETHICS AND DISSEMINATION: Yenepoya University Ethics Committee, India has approved the study protocol (YUEC/148/2016 on 18 February 2016). It complies with the Declaration of Helsinki, local laws and the International Council for Harmonization-good clinical practices. TRIAL REGISTRATION NUMBER: CTRI/2016/02/006691; Pre-results.