Shyam Sunder Tummanapalli

UNSW Sydney | UNSW · School of Optometry and Vision Science

SIGNIFICANCE This study establishes an increased risk of developing dry eye disease (DED) in patients with diabetic peripheral neuropathy using validated diagnostic criteria for both conditions. PURPOSE The disruption of ocular surface homeostasis has been associated with diabetes. However, it remains unclear if this association is independently i...

Purpose: This study aims to determine the effects of SGLT2 inhibitors on corneal dendritic cell density and corneal nerve measures in type 2 diabetes. Methods: Corneal dendritic cell densities and nerve parameters were measured in people with type 2 diabetes treated with SGLT2 inhibitors (T2DM-SGLT2i) [n = 23] and those not treated with SGLT2 in...

Aim: To determine the impact of chronic kidney disease on corneal nerve measures and dendritic cell counts in type 2 diabetes. Methods: In vivo corneal confocal microscopy images were used to estimate corneal nerve parameters and compared in people with type 2 diabetes with chronic kidney disease (T2DM-CKD) (n = 29) and those with type 2 diabete...

Clinical relevance: Hand hygiene is important to reduce the spread of microbes in clinical settings. Hand sanitisers that last longer may be beneficial. Background: Longevity of hand sanitisation products on fingers and hands may be important to help reduce microbial transmission. The current study evaluated the persistence of disinfection of th...

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). SARS-CoV-2 belongs to the group IV Coronavirinae in the subfamily Orthocoronavirinae, order Nidovirales, with four genera: alphacoronavirus, betacoronavirus, gammacoronavirus, and deltacoronavirus (not to be confused with the variants...

Clinical relevance Optometrists have been advised to wear face masks during the COVID-19 pandemic. This study examined whether face masks were equally protective against transmission of microbes. Background The aim of the current study was to examine the ability of face masks to reduce transmission of microbes in aerosols and during speech. Metho...

Clinical relevance: There is potential benefit in analysing corneal nerve tortuosity as a marker for assessment and progression of systemic diabetic neuropathy. Background: The aim of this work was to determine whether tortuosity significantly differs in participants with type 1 (T1DM) and type 2 (T2DM) diabetes compared to controls and whether...

Nitric oxide (NO) has a wide array of biological functions including the regulation of vascular tone, neurotransmission, immunomodulation, stimulation of proinflammatory cytokine expression and antimicrobial action. These functions may depend on the type of isoform that is responsible for the synthesis of NO. NO is found in various ocular tissues p...

Background There is a strong association between the metabolic syndrome in diabetes and the development of peripheral neuropathy, however the pathophysiological mechanisms remain unknown. Methods Participants with type 2 diabetes and metabolic syndrome (T2DM/MetS, n = 89) and type 2 diabetes alone (T2DM, n = 59) underwent median nerve ultrasound a...

Isolation of antimicrobial‐resistant microbes from ocular infections may be becoming more frequent. Infections caused by these microbes can be difficult to treat and lead to poor outcomes. However, new therapies are being developed which may help improve clinical outcomes. This review examines recent reports on the isolation of antibiotic‐resistant...

Aim To examine the associations between of continuous overlapping net glycaemic action (CONGA), percentage time in hyperglycaemia (%HG) or normoglycaemia (%NG) and peripheral nerve structure and function in type 1 diabetes. Methods Twenty‐seven participants with type 1 diabetes underwent continuous glucose monitoring followed by corneal confocal m...

Aims: To determine the utility of corneal confocal microscopy and tear neuromediator analysis in the diagnosis of diabetic peripheral neuropathy (DPN) as a result of type 1 and type 2 diabetes. Methods: Seventy individuals with either type 1 diabetes or type 2 diabetes (T1D/T2D) underwent corneal confocal microscopy to assess the corneal nerve mo...

Objective Corneal confocal microscopy (CCM) has been identified as a non-invasive technique to assess corneal nerve fiber morphology. It is not known how corneal nerve changes relate to measures of peripheral nerve function in diabetic peripheral neuropathy (DPN). The present study investigates the relationship between nerve structure and function...

Purpose: To evaluate the effect of age, gender and body mass index (BMI) on the levels of tear film neuromediators and corneal nerve parameters in healthy individuals. Methods: Twenty-six healthy subjects were screened for any neurological deficits. The concentration of substance P and calcitonin gene-related peptide (CGRP) in tears was measured b...

Objective: To explore the changes that occur in the concentrations of substance P (SP) and calcitonin gene-related peptide (CGRP) in tears as a result of corneal denervation and its association with diabetic peripheral neuropathy (DPN). Methods: Sixty-three individuals with type 1 diabetes/type 2 diabetes (T1D/T2D) and 34 age-matched healthy con...

Objective: To investigate the association between the concentration of tear film substance P and diabetic peripheral neuropathy (DPN) in type1 and type 2 diabetes. Conclusions: The concentration of substance P in tears is reduced in type 1 with DPN only, although corneal nerve physiology is changed with type1 and type 2 DPN. This may indicate a dif...

Aims To investigate changes in corneal nerve morphology in Type 2 diabetes and to establish relationships between in vivo corneal confocal microscopy and markers of peripheral nerve structure and function. Participants and methods We recruited 57 participants with Type 2 diabetes and 26 healthy controls of similar age and sex distribution. We also...

AIMS: To investigate changes in corneal nerve morphology in Type 2 diabetes and to establish relationships between in vivo corneal confocal microscopy and markers of peripheral nerve structure and function. PARTICIPANTS AND METHODS: We recruited 57 participants with Type 2 diabetes and 26 healthy controls of similar age and sex distribution. We al...

Background: Patients with chronic kidney disease (CKD) in type 2 diabetes (T2DM) typically manifest with severe neuropathy. Corneal confocal microscopy (CCM) and axonal excitability are novel techniques that serve as biomarkers for the structure and function of peripheral nerves. Aim: This study aimed to investigate the relationship between CCM, a...

Abstract Purpose : To investigate morphological changes in the bulbar conjunctiva after mini-scleral contact lens (MScCL) wear using in vivo confocal microscopy (IVCM), and to explore the relationship between conjunctival changes at the cellular level and MScCL settling. Methods : 12 healthy subjects (age range 22-24 years; 5M, 7F) were fitted wit...

Abstract Purpose : To examine the ability of corneal nerve fibre assessment and axonal ion-channel function to diagnose diabetic peripheral neuropathy (DPN). Methods : A total of 36 subjects with type 1 diabetes and 10 age-matched controls underwent confocal microscopy to assess corneal nerve fibre length, density area, width, branch density, and...

To investigate the relationship between corneal nerve structure and axonal ion-channel function in patients with and without DPN.

Diabetes mellitus is a chronic disease that results from inadequate insulin production or ineffective insulin utilization. It is one of the most common systemic diseases worldwide with increasing prevalence. Diabetes mellitus is associated with premature mortality, macrovascular complications such as cardiovascular disease, and microvascular compli...

Purpose To investigate and compare the efficacy of axial and tangential corneal topography maps obtained using the Orbscan IIz scanning-slit device to distinguish differences in eyes with subclinical keratoconus from normal eyes. Setting LV Prasad Eye Institute, Hyderabad, India. Design Retrospective cross-sectional study. Methods Axial and tangent...

Purpose To estimate the variation in topography parameters due to inter session variations, diurnal variation and variability following pupillary dilation, to accurately identify progression in keratoconus. Methods Corneal topography was performed using the Orbscan IIz system on 100 normal eyes of 100 subjects and on 100 eyes of 100 subjects with c...

PURPOSE: To determine and compare corneal elevation and thickness indices, thereby formulating a reliable index to distinguish eyes with pellucid marginal degeneration (PMD) from keratoconus eyes and normal (control) eyes. SETTING: LV Prasad Eye Institute, Hyderabad, India. DESIGN: Initial model-building retrospective study. METHODS: Anterior and p...

Purpose: To investigate the accuracy of Back Optic Zone Radius (BOZR, base curve) measurements with manual keratometer for spherical polymethylmethacrylate (PMMA) lenses. Methods: 100 spherical PMMA contact lenses were selected randomly from the trial sets. One investigator measured the BOZR with radiuscope. The second investigator measured the BOZ...