Namperumalsamy V Prajna

• Aravind Eye Hospital

Purpose To assess the clinical utility of the clustered regularly interspaced short palindromic repeats/Cas12a-based RID-MyC assay in diagnosing Fungal Keratitis (FK) in cases where conventional smear and culture methods fail to identify the causative pathogen. Methods This retrospective case series included 5 patients with clinically suspected FK...

Objective This study develops and evaluates multimodal machine learning models for differentiating bacterial and fungal keratitis using a prospective representative dataset from South India. Design Machine learning classifier training and validation study. Participants Five hundred ninety-nine subjects diagnosed with acute infectious keratitis at...

Purpose: This study aimed to analyze the clinical presentation, treatment outcomes, and histopathology features of ocular surface squamous neoplasia (OSSN) in a South Indian population and correlate the area of lesions to the histopathological grade/severity of carcinoma in situ (CIN) and squamous cell carcinoma (SqCC) invasive and noninvasive tum...

Purpose The purpose of this study was to assess the association between antifungal susceptibility as measured by minimum inhibitory concentration (MIC) and clinical outcomes in fungal keratitis. Methods This pre-specified secondary analysis of the Mycotic Ulcer Treatment Trial II (MUTT II) involved patients with filamentous fungal keratitis presen...

Purpose The Steroids and Cross-linking for Ulcer Treatment Trial is an NIH-funded international, randomized, double-masked, sham and placebo-controlled clinical trial to determine the benefit of adjunctive corneal cross-linking with riboflavin and/or topical difluprednate in addition to topical antibiotic drops for treatment of smear-positive bacte...

Background Infectious keratitis secondary to fungus or acanthamoeba often has a poor outcome despite receiving the best available medical therapy. In vitro rose bengal photodynamic therapy (RB-PDT) appears to be effective against fungal and acanthamoeba isolates (Atalay HT et al., Curr Eye Res 43:1322–5, 2018, Arboleda A et al. Am J Ophthalmol 158:...

Purpose To identify weather variables associated with pathogens contributing to infectious conjunctivitis globally. Methods Sample collection and pathogen identification from patients with acute infectious conjunctivitis was performed from 2017 to 2023. We linked pathogens identified from 13 sites across 8 countries with publicly available weather...

Importance Infectious conjunctivitis can lead to corneal involvement and result in ocular morbidity. The identification of biomarkers associated with corneal involvement has the potential to improve patient care. Objective To identify biomarkers in patients with acute infectious conjunctivitis. Design, Setting, and Participants This cross-section...

Importance: Infectious conjunctivitis can lead to corneal involvement and result in ocular morbidity. The identification of biomarkers associated with corneal involvement has the potential to improve patient care. Objective: To identify biomarkers in patients with acute infectious conjunctivitis. Design, setting, and participants: This cross-sect...

Objectives To determine the associated pathogen during the 2023 conjunctivitis outbreak in Vietnam Methods RNA-sequencing was used to identify pathogens before and during the outbreak. Results 24 patients with infectious conjunctivitis between March and October 2023 from Hai Yen Vision Institute in Vietnam were swabbed. Coxsackievirus A24v was th...

Objective The objective of this study was to develop a rapid and accurate clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a-based molecular diagnostic assay (Rapid Identification of Mycoses using CRISPR, RID-MyC assay) to detect fungal nucleic acids and to compare it with existing conventional mycologic methods for the diagn...

Importance Microbial keratitis (MK) is a common cause of unilateral visual impairment, blindness, and eye loss in low-income and middle-income countries. There is an urgent need to develop and implement rapid and simple point-of-care diagnostics for MK to increase the likelihood of good outcomes. Objective To evaluate the diagnostic performance of...

Purpose: Rapid and accurate diagnosis of microbial keratitis (MK) could greatly improve patient outcomes. Here, we present the development of a rapid, accessible multicolour fluorescence imaging device (FluoroPi) and evaluate its performance in combination with fluorescent optical reporters (SmartProbes) to distinguish bacterial Gram status. Furth...

Purpose: The aim of this study was to validate the C-DU(KE) calculator as a predictor of treatment outcomes on a data set derived from patients with culture-positive ulcers. Methods: C-DU(KE) criteria were compiled from a data set consisting of 1063 cases of infectious keratitis from the Steroids for Corneal Ulcer Trial (SCUT) and Mycotic Ulcer...

Purpose: Understanding the association between social determinants of health (SDoHs) and microbial keratitis (MK) can inform underlying risk for patients and identify risk factors associated with worse disease, such as presenting visual acuity (VA) and time to initial presentation. Methods: This was a cross-sectional study was conducted with pat...

Purpose: The aim of this study was to facilitate deep learning systems in image annotations for diagnosing keratitis type by developing an automated algorithm to classify slit-lamp photographs (SLPs) based on illumination technique. Methods: SLPs were collected from patients with corneal ulcer at Kellogg Eye Center, Bascom Palmer Eye Institute,...

This Viewpoint offers examples of the causes of infectious keratitis around the world and emphasizes the need for vigilance among ophthalmologists to reduce the risk of sight-threatening complications.

Purpose: To determine whether convolutional neural networks can detect morphological differences between images of microbiologically positive and negative corneal ulcers. Methods: A cross-sectional comparison of prospectively collected data consisting of bacterial and fungal cultures and smears from eyes with acute infectious keratitis at Aravin...

Purpose of Review To review and perform a meta-analysis of individual patient data from observational studies describing medical treatment of Pythium keratitis. The outcomes of interest were therapeutic penetrating keratoplasty (TPK) and globe removal (evisceration, enucleation, or exenteration); the main exposures were linezolid and azithromycin u...

Purpose: There is a need to understand physicians' diagnostic uncertainty in the initial management of microbial keratitis (MK). This study aimed to understand corneal specialists' diagnostic uncertainty by establishing risk thresholds for treatment of MK that could be used to inform a decision curve analysis for prediction modeling. Methods: A...

Amongst the treatable cause of blindness among young people, fungal keratitis ranks high. There are an estimated 1,051,787 to 1,480,916 eyes affected annually, with 8–11% of patients having to have the eye removed. Diagnosis requires a corneal scraping, direct microscopy and fungal culture with a large number of airborne fungi implicated. Treatment...

Background Seasonal outbreaks of infectious conjunctivitis remain a public health issue. Determination of outbreak etiologies in the context of a worldwide pandemic may provide useful information to guide public health strategies. The aim of this study was to identify pathogens associated with outpatient infectious conjunctivitis during the COVID-1...

Background Viral conjunctivitis (pink eye) can be highly contagious and is of public health importance. There remains significant debate whether SARS-CoV-2 can present as a primary conjunctivitis. The aim of this study was to identify pathogens associated with outpatient infectious conjunctivitis during the COVID-19 Delta surge. Methods This prosp...

Purpose: To describe the process development of a multimodal intervention and the pre- and postintervention results on the completeness of case records of patients with penetrating ocular trauma in a high-volume tertiary eye care hospital in south India. Methods: A multimodal intervention including an objective-validated case sheet template, an...

Background Acanthamoeba keratitis is challenging to treat and thought to result in poor outcomes, but very few comparative studies exist to assess whether ulcers caused by Acanthamoeba are worse than those caused by bacteria or fungus. Methods In a retrospective cohort study, all cases of smear- or culture-proven Acanthamoeba keratitis diagnosed f...

Purpose To develop computer vision models for image-based differentiation of bacterial and fungal corneal ulcers and compare their performance against human experts. Design Cross-sectional comparison of diagnostic performance. Subjects Patients with acute, culture-proven bacterial or fungal keratitis from 4 centers in South India. Methods 5 conv...

Purpose: The purpose of this study was to determine whether astigmatism or corneal scarring is mediating the reduced visual acuity among patients with fungal keratitis randomized to corneal cross-linking (CXL). Design: This was a prespecified exploratory outcome from an outcome-masked, 2 × 2 factorial design, randomized controlled clinical trial...

Importance Antifungal resistance has been shown to impact treatment success, but research analyzing antifungal resistance is scarce. Objective To evaluate changes in antifungal resistance over time. Design, Setting, and Participants Ad hoc analysis of 3 randomized clinical trials including consecutive patients 18 years and older presenting with s...

Introduction Although antibiotics are successful at achieving microbiological cure in infectious keratitis, outcomes are often poor due to corneal scarring. Ideal treatment of corneal ulcers would address both the infection and the inflammation. Adjunctive topical steroid treatment may improve outcomes by reducing inflammation. Corneal cross-linkin...

Purpose To determine if smartphone photography could be a useful adjunct to blindness prevalence surveys by providing an accurate diagnosis of corneal opacity. Methods A total of 174 patients with infectious keratitis who had undergone corneal culturing over the past 5 years were enrolled in a diagnostic accuracy study at an eye hospital in South...

This study quantifies the performance of an international cohort of cornea specialists in image-based differentiation of bacterial and fungal keratitis, identifying significant regional variation and establishing a reference standard for comparison against machine learning models.

Purpose: The aim of this study was to report a case of human keratoconjunctivitis caused by both Newcastle disease virus (NDV) and human adenovirus. Methods: A 32-year-old-man presented with an acute unilateral keratoconjunctivitis that resolved with corneal scarring. On presentation, his conjunctival swab was collected for metagenomic sequencin...

Purpose: To report structural changes observable in in vivo confocal microscopy (IVCM) in keratoconic corneas < 400 μm treated with hypotonic riboflavin and collagen crosslinking (CXL). Methods: Ten eyes of ten patients with progressive keratoconus and corneal thickness between 350 and 399 μm underwent CXL with hypotonic riboflavin. IVCM was per...

Corneal involvement in HIV-infected individuals may be broadly classified into two categories, namely, infectious and noninfectious with the vast majority of manifestations occurring in the former. In this article, we shall focus on these two categories and strive to highlight those presentations that should alert the clinician to suspect underlyin...

Purpose: The purpose of this article was to evaluate the impact of sample collection order on the diagnostic yield of metagenomic deep sequencing (MDS) for determining the causative pathogen in infectious keratitis. Methods: We performed a cross-sectional diagnostic test evaluation among subjects with infectious keratitis at Aravind Eye Hospital...

Purpose: The aim of this study was to study the clinical and economic impact of a teleophthalmology-based vision center (VC) in the management of corneal diseases in rural south India. Methods: Data of patients with corneal disorders who visited the VC in the year 2019 were analyzed for the total number of outpatient visits, the proportion of co...

SYNOPSIS Background Fusarium keratitis is an infection of the cornea that often results in corneal perforation requiring corneal transplantation even with topical ocular antifungal therapy. The polyene natamycin remains the current antifungal of choice for Fusarium keratitis, but prompt sterilization of the cornea is often not achieved with contem...

Fungal keratitis (FK) accounts for approximately half of the microbial keratitis encountered in low middle income countries (LMICs) and predominantly affect the working rural-poor. FK causes significant morbidity with the majority of patients left with moderate or worse visual impairment and approximately 25% requiring expensive and often unsuccess...

Purpose: To determine whether there is a benefit to adjuvant corneal cross-linking (CXL) for bacterial keratitis. Methods: This is an outcome-masked, randomized controlled clinical trial. Consecutive patients presenting with a smear-positive bacterial ulcer at Aravind Eye Hospitals at Madurai, Pondicherry, and Coimbatore in India were enrolled....

Importance Corneal opacity is a leading cause of visual impairment worldwide; however, the specific features of corneal scars, which decrease visual acuity, have not been well characterized. Objective To investigate which features of a postfungal keratitis corneal scar contribute to decreased visual acuity after an episode of infectious keratitis...

Purpose: To determine if there is a benefit to adjuvant corneal crosslinking (CXL) and to compare natamycin versus amphotericin B for filamentous fungal keratitis. Design: Outcome-masked, 2×2 factorial design, randomized controlled clinical trial. Participants: Consecutive patients presenting with moderate vision loss from a smear-positive fun...

Purpose: To study the outcomes of Descemet membrane (DM) suturing for moderate to severe Descemet membrane detachment (DMD) after cataract surgery. Methods: This is a retrospective case review of all patients who underwent DM suturing for moderate to severe DMD after cataract surgery in a tertiary training eye care hospital from January 2017 to...

Purpose: To determine the repeatability and reproducibility of anterior segment optical coherence tomography (AS-OCT) and Scheimpflug photography for several measurements of corneal scars, including scar size, scar depth, and corneal thickness. Methods: A series of patients treated for fungal keratitis at a tertiary eye care center in South India w...

Purpose: To report 2 patients with colonization of therapeutic contact lens with dematiaceous fungi. Methods: Case report. Results: The first patient had a retained soft contact lens on an opaque cornea for 4 years with brownish black multiple colonies on the soft contact lens and culture grew Bipolaris spp. The second patient was on therapeut...

Purpose: To report the clinical features and outcomes of toxic keratitis after application of powdered custard apple seeds for hair washing for head lice infestation. Methods: Retrospective review of all patients with toxic keratitis after application of powdered custard apple seed for head lice infestation during the time period from January 20...

Objective: To compare oral voriconazole versus placebo in addition to topical antifungals in the treatment of filamentous fungal keratitis. Design: Non-prespecified, secondary case-control analysis from a multicenter, double-masked, randomized placebo-controlled clinical trial STUDY PARTICIPANTS: Patients with smear-positive filamentous fungal u...

Purpose: We compare results from regression discontinuity (RD) analysis to primary results of a randomized controlled trial (RCT) utilizing data from two contemporaneous RCTs for treatment of fungal corneal ulcers. Methods: Patients were enrolled in the Mycotic Ulcer Treatment Trials I and II (MUTT I & MUTT II) based on baseline visual acuity: pati...

Purpose: The purpose of this study is to describe the presenting features, management strategies, and clinical outcome following bee sting injury to the cornea. Methods: Retrospective case series involving 11 eyes of 11 patients with corneal bee sting injuries who presented over a period of 2 years. Nine of these 11 eyes had the presence of inta...

Purpose: To identify fungal keratitis patients who are at risk of a poor outcome and may benefit from closer follow-up or more aggressive treatment. Design: Secondary analysis of randomized clinical trial data. Subjects: Patients presenting with a smear-positive filamentous fungal ulcer, visual acuity of 20/400 or worse, and who subsequently h...

The Mycotic Ulcer Treatment Trial I (MUTT I) demonstrated the superiority of natamycin compared with voriconazole for the treatment of filamentous fungal keratitis.¹ This and other recent trials²,3 suggest that natamycin should be the treatment of choice for filamentous fungal keratitis. A survey of experts (approximately 800 surveyed; 92 responden...

Aim: To study the demographic profile, clinical features, treatment outcome and ocular morbidity of smear-positive microsporidial keratoconjunctivitis. Methods: Retrospective case series of all patients with clinical features of microsporidial keratoconjunctivitis and who were smear positive for the same on Gram stain from January 2013 to Decemb...

Purpose: To determine the diagnostic accuracy of in vivo confocal microscopy (IVCM) for moderate to severe microbial keratitis (MK). Design: Double-masked prospective cohort study. Participants: Consecutive patients presenting to Aravind Eye Hospital, Madurai, India, between February 2012 and February 2013 with MK (diameter ≥3 mm, excluding de...

Purpose To study the risk factors, microbiological profile and clinical outcomes of infectious keratitis affecting paediatric patients. Study design Retrospective case series. Methods Review of case records of paediatric patients (0–16 years) diagnosed with infectious keratitis who presented to Aravind Eye Hospital, Madurai, India during January 20...

To assess the efficacy of corneal cross linking (CXL) as an adjuvant to appropriate antifungal therapy in non-resolving deep stromal fungal keratitis. Randomized clinical trial METHODS: Eyes with culture-positive deep stromal fungal keratitis not responding to appropriate medical therapy for a period of two weeks were randomized to receive either a...

Objective To assess the trends in microbiological organisms identified from corneal scrapings from patients with infectious keratitis at a tertiary care medical centre in South India. Methods We reviewed the records of the microbiology laboratory at Aravind Eye Hospital in Madurai, India, from 2002 until 2012. We identified the microbiological caus...

Purpose: To validate computer software developed to assess digital corneal photographs of fungal keratitis in clinical research. Methods: A cornea specialist and five medical students (after training) graded on two occasions 100 corneal photographs of patients with fungal keratitis using Optscore software. Variables assessed were lesion area, lo...

This is a commentary on article Sharma N, Chacko J, Velpandian T, Titiyal JS, Sinha R, Satpathy G, Tandon R, Vajpayee RB. Comparative evaluation of topical versus intrastromal voriconazole as an adjunct to natamycin in recalcitrant fungal keratitis. Ophthalmology. 2013 Apr;120(4):677-81.

Retrospective studies have suggested that, compared with bacterial keratitis, fungal keratitis has particularly poor outcomes.1 An unbiased analysis would ideally be performed in a prospective, standardized fashion. Herein, we compare clinical outcomes in ulcers due to bacteria and fungus using data collected from 2 similarly structured prospective...

Purpose: To perform a Bayesian analysis of the Mycotic Ulcer Treatment Trial I (MUTT I) using expert opinion as a prior belief. Methods: MUTT I was a randomized clinical trial comparing topical natamycin or voriconazole for treating filamentous fungal keratitis. A questionnaire elicited expert opinion on the best treatment of fungal keratitis be...

Background The involvement of VSX1 gene for the genetic basis of keratoconus is unclear and controversial. The genetic screening of VSX1 from different ethnic populations can enlighten this subject. The aim of the present study is to investigate the role of VSX1 gene in patients with sporadic cases of keratoconus from South India. Methods The VSX1...

Till date there is no exclusive marker for human corneal epithelial stem cells (CESCs). In this study, our strategy is to combine high expression of ABCG2, a putative SC marker with high N/C ratio to develop a specific method for identification of CESCs. Limbal/corneal epithelial cells (LECs/CECs) were isolated from cadaver eyes by enzymatic treatm...

Fusarium is the major causative agent of fungal infections leading to corneal ulcer (keratitis) in Southern India and other tropical countries. Keratitis caused by Fusarium is a difficult disease to treat unless antifungal therapy is initiated during the early stages of infection. In this study tear proteins were prepared from keratitis patients cl...

Objective To compare topical natamycin vs voriconazole in the treatment of filamentous fungal keratitis. Methods This phase 3, double-masked, multicenter trial was designed to randomize 368 patients to voriconazole (1%) or natamycin (5%), applied topically every hour while awake until reepithelialization, then 4 times daily for at least 3 weeks. El...

Fusarium and Aspergillus species are aggressive corneal pathogens, and even with proper treatment, can lead to poor outcomes.1 Voriconazole is effective in vitro against Aspergillus species, but may not perform as well against Fusarium species.2 We undertook a clinical trial comparing topical voriconazole versus topical natamycin, with the overall...

: Previous studies suggest that fungal keratitis is more common in hot humid climates and that bacterial keratitis is independent of seasonal variation. This study analyzes seasonal trends in the incidence of fungal and bacterial keratitis at the Aravind Eye Hospital in southeast India. : Using microbiology records from August 2006 to July 2009, re...

We report a case of an agricultural worker presenting with corneal infiltrate following ocular injury with a rice husk. On examination, a superficial corneal foreign body was removed and sent for culture, which grew Pantoea ananatis. This is, to our knowledge, the first clinical case report of Pantoea ananatis causing corneal infiltrate.

The purpose of this study was to determine whether clinical signs of infectious keratitis can be used to identify the causative organism. Eighty photographs of eyes with culture-proven bacterial keratitis or smear-proven fungal keratitis were randomly selected from 2 clinical trials. Fifteen cornea specialists from the F. I. Proctor Foundation and...

In light of the increased incidence of contact lens associated Acanthamoeba keratitis in recent years, this study analyzed longitudinal trends of its incidence among predominantly non-contact lens wearers in a high-volume referral center in South India. A retrospective analysis of microbiology laboratory records at the Aravind Eye Hospital from 198...

To analyze the minimum inhibitory concentration (MIC) of isolates from fungal keratitis to natamycin and voriconazole and to assess the relationship between organism, MIC, and clinical outcome. Data were collected as part of a randomized, controlled, double-masked clinical trial. Main outcome measures included best spectacle-corrected visual acuity...

Animal studies have demonstrated that female mice may have a slower re-epithelialisation following corneal injury compared with males.1 However, it is unknown if this translates to humans. In this report, we compare re-epithelialisation time in men and women using data collected as part of a prospective, randomised clinical trial on fungal corneal...

To identify adult human buccal epithelial stem cells (SCs) on the basis of two parameters (high p63 expression and greater nucleus/cytoplasmic (N/C) ratio) and to evaluate clinical efficacy of ex-vivo expanded autologous epithelium in bilateral limbal SC-deficient (LSCD) patients. The epithelial cells were isolated from buccal biopsy and cultured o...

Filamentous fungi of the genera Aspergillus and Fusarium are major causes of corneal ulcers in the United States and in the developing world and result in significant visual impairment and blindness. RNA was extracted from 110 patients with corneal ulcers in southern India within 1 week of infection with either Fusarium solani or Aspergillus flavus...

The proteomic profile of tear fluid is of fundamental interest in eye research. In this study we optimized the tear sample preparation method for two-dimensional (2D) analysis and determined the protein profile of tear fluid from healthy males and females. To find the most efficient method for tear sample preparation, four widely applied precipitat...

Filamentous fungi are important aetiological agents of keratitis globally.1 Hyaline hyphomycetes including Fusarium and Aspergillus spp. are most common, but dematiaceous fungi such as Curvularia and Bipolaris spp. constitute approximately 20% of cases.2 3 Commonly reported signs of fungal keratitis include feathery edges, raised lesions, hypopyon,...

The purpose of the present study was to evaluate the kinetics of single and multiple doses of topical, non-preserved voriconazole (VZ) in human eyes. For single dose kinetics, 119 patients undergoing cataract surgery were divided into group I and group II and each group received a single drop (30 µl) of either 1% or 0.1% VZ formulation. Aqueous hum...

Infectious keratitis is a major cause of monocular blindness worldwide.1 Although fungal ulcers are relatively uncommon in developed nations, they occur frequently in developing countries, especially those in tropical regions. In South India, up to half of infectious ulcers are fungal.2 Fungal ulcers are notoriously difficult to treat compared with...

To conduct a therapeutic exploratory clinical trial comparing clinical outcomes of treatment with topical natamycin vs topical voriconazole for fungal keratitis. The multicenter, double-masked, clinical trial included 120 patients with fungal keratitis at Aravind Eye Hospital in India who were randomized to receive either topical natamycin or topic...

Fungal keratitis causes significant morbidity, especially in tropical climates, and is notoriously difficult to manage. The choice of antifungal agent for fungal keratitis remains largely empirical, with no consensus on the role of susceptibility testing in guiding therapy. Studies suggest that susceptibility and outcome may be associated in system...

Mutations in COL8A2 gene which encodes the collagen alpha-2 (VIII) chain have been identified in both familial and sporadic cases of Fuchs endothelial corneal dystrophy (FECD). Heterozygous mutations in the SLC4A11 gene are also known to cause late-onset FECD. Therefore we screened for COL8A2, SLC4A11 gene variants in Indian FECD patients. Eighty p...

Evaluate the effectiveness of an interactive cognitive computer simulation for teaching the hydrodissection portion of cataract surgery compared with standard teaching and to assess the attitudes of residents about the teaching tools and their perceived confidence in the knowledge gained after using the tools. Case-control study. Residents at acade...

The purpose of this study was to evaluate the subset of limbal epithelial cells with greater nucleus-to-cytoplasm (N/C) ratio expressing high levels of p63 for their slow-cycling property, a characteristic feature of stem cells (SCs). Limbal and peripheral corneal explant cultures were pulse labeled with 5-5-bromo-2'-deoxyuridine (BrdU) for 5 days,...

The cornea is a transparent avascular tissue that provides a protective barrier from the external environment and also serves as the main refractive element of the visual system. The corneal transparency relies on the normal functioning of its three tissue layers, epithelium, stroma and endothelium. Under normal circumstances, the superficial cells...