Shyam Sunder Tummanapalli

PhD Candidate

PhD Candidate

Research Title: Evaluation of tear neuropeptides in diabetic peripheral neuropathy

Supervisors: Dr Maria Markoulli, Professor Mark Willcox and Dr Ann Poynten





Loss of sensation in the periphery of the body, recurrent ulcers of the feet and, in extreme cases, amputation of limbs can occur in people with diabetes due to diabetic peripheral neuropathy. This neuropathy affects up to 70% of people with diabetes. It has been estimated, worldwide, one lower limb is amputated every 20 seconds as a consequence of this condition, resulting in staggering costs for both the patient and the health care system. Early detection of the neuropathy is essential to help reduce the consequences of this disease. However, current diagnostic tests are either invasive or not capable of detecting early changes. Recently a reduction in the number of nerves at the front of the eye (the cornea) has been found to be predictive of diabetic peripheral neuropathy. However, assessing these nerves is a specialised research technique not easily performed by non-specialists. These nerves release proteins known as neuropeptides into the tears that coat the eye – a reduction in nerves results in a reduction in these neuropeptides. The aim of my research is to identify the tear film neuropeptides associated with this neuropathy and assess whether their concentration in tears can be used as a way to diagnose and monitor the disease in its early stages.



Shyam Sunder earned his graduate degree in Clinical Optometry from Bharati Vidyapeeth Deemed University in Pune, India in 2005. He worked as Consultant Optometrist, where his interaction expanded to encompass a wider range of patients at one of the largest chains of eyewear solutions for two years in Hyderabad. Later he worked in various roles as a Consultant Optometrist, a Research Optometrist and as a Senior Lecturer at LV Prasad Eye Institute and Professor Brien Holden Eye Research Centre for nine years.



  1. Yan A, Issar T, Tummanapalli SS, Markoulli M, Kwai NCG, Poynten AM, Krishnan AV. Relationship between corneal confocal microscopy and markers of peripheral nerve structure and function in Type 2 diabetes. Diabet Med. 2019 Mar 21. doi:10.1111/dme.13952. [Epub ahead of print] PubMed PMID: 30897245
  2. Markoulli M, Flanagan J, Tummanapalli SS, Wu J, Willcox M. The impact of diabetes on corneal nerve morphology and ocular surface integrity. Ocul Surf. 2018 Jan;16(1):45-57. PubMed PMID: 29113918
  3. Tummanapalli SS, Markoulli M. Dry eyes and Diabetes. New Zealand Optics 2016



2019 – Travel grant to attend the International Society for Contact Lens Research Scientific  (ISCLR) Meeting -2019, Singapore 

2019 - Juvenile Diabetes Research Foundation travel grant

2017 - Best photo award for “Whirlpool in the eye”- A montage of in-vivo confocal images of corneal nerves demonstrating whorl-like pattern of the corneal sub-basal nerve plexus. School of optometry and vision sciences photo competition, University of New South Wales, Australia

2016 - University of New South Wales Tuition Fee Scholarship (TFS) for study toward a PhD in the Optometry and Vision Science.

2015 - Best Scientific Poster Award. Tummanapalli SS, Potluri H, Vaddavalli PK, Sangwan VS. “Efficacy of Axial and Tangential Corneal Topography Maps in Detecting Subclinical Keratoconus: A novel diagnostic index”. ESO's International vision science and optometry conference (EIVOC), Chennai, India

2015 - ESO's International Vision science and Optometry Conference (EIVOC) travel grant, Chennai, India

2013 - Australian Leadership Awards Fellowship (Brien Holden Vision Institute, Sydney)

2010 - Best scientific poster award. Tummanapalli SS, Maseedupally V, Mandathara P, Rathi VM, Sangwan VS “Evaluation of corneal elevation and thickness indices in pellucid marginal corneal degeneration and keratoconus”. ESO's International vision science and optometry conference (EIVOC), Chennai, India



2019 -Tummanapalli SS, Willcox M, Issar T, Yan A, Pisarcikova J, Kwai N, Poynten A, Krishnan A, Markoulli M. Reduced tear film substance P concentration is associated with diabetic peripheral neuropathy. Association for Research in Vision and Ophthalmology (ARVO), Vancouver, Canada. (Poster)

2018 - Tummanapalli SS, Willcox M, Issar T, Kwai N, Poynten A, Krishnan A, Markoulli M. Assessment of corneal nerve structure and peripheral nerve function in detection of diabetic peripheral neuropathy. Association for Research in Vision and Ophthalmology (ARVO), Honolulu, Hawaii. (Poster)

2018 - Tummanapalli SS, Issar T, Kwai N, Poynten A, Krishnan A, Willcox M, Markoulli M. Corneal confocal microscopy detects peripheral neuropathy in type 2 diabetes with chronic kidney disease". Australasian Diabetes Congress, Adelaide. Australia. (Oral)

2017 - Tummanapalli SS, Issar T, Kwai N, Poynten A, Krishnan A, Willcox M, Markoulli M. The relationship between structural and electrophysiological measures of peripheral nerves in human type 1 diabetes. International Diabetes Federation (IDF) Congress, Abu Dhabi, United Arab Emirates. (Poster)



2017 - Student member, The American Academy of Optometry

2016 - Student Member, Cornea & Contact Lens Society of Australia

2015 - Member, Optometry Council of India

2010 - Student Member, The Association for Research in Vision and Ophthalmology