Dr Ehsan Vaghefi
BSc, MSc, PhD
Dr Ehsan Vaghefi holds a joint appointment as a research fellow (Molecular Vision Lab and Auckland Bioengineering Institute) and lecturer in Physiological Optics (Department of Optometry and Vision Sciences). His appointment is a strategic initiative to develop a joint research-led teaching program in Physiological Optics. It also provides him access to a talented pool of potential graduate students with a mix of optics and modelling backgrounds, to perform both the computational and experimental portions of his research.
Dr Vaghefi received his Bachelor of Science in Biomedical Engineering from the Polytechnic University of Tehran in 2005 for his bachelor project based on x-ray based biomedical imaging systems. He continued his education at the University of New South Wales where he obtained his Master of Science in Biomedical Sciences in 2006. The focus of his masters project was computer modelling of the heart's electrical activity. He then joined the Auckland Bioengineering Institute to model and image the microcirculation of the ocular lens for his doctoral thesis.
Dr Vaghefi has been developing magnetic resonance imaging techniques to non-invasively monitor the fluid fluxes inside the ocular lens. His achievements have been published in highly respected international biomedical journals.
Research | Current
Ehsan is a member of the ABI Special Sense Organs research project.
Currently he is continuing his research in the fields of
- Clinically applied physiological optics
- Cataracts research
- Ocular biomedical imaging
- Ocular computational modelling
He has the following funded postgraduate projects available:
- Biological glass: The molecular and cellular determinations of the optical properties of the ocular lens
Although age-related changes to the optical properties of the ocular lens are the leading causes of refractive error (presbyopia) and blindness (cataract), we know little about how the optical properties of the lens are established and maintained at the molecular and cellular levels. Like any glass lens, our biological lens suffers from inherent refractive error, but being a living tissue it compensates for these errors by overexpressing crystallin proteins to create a gradient of refractive index (GRIN). It is our hypothesis that differences in crystallin subtype expression and processing combined with lens structure and function generate and maintain the GRIN.
We have recently shown that inhibition of lens transport increases lens water content and decreases the GRIN, suggesting the GRIN is actively maintained and that changes in lens physiology will affect overall vision quality. In this application will investigate how lens structure and function interact to establish and maintain the GRIN, and how alterations in these mechanisms affect our quality of vision. This research involves stressing the lens physiology with known external stimuli and then measure its GRIN profile, using an existing laser ray-tracing system. These optical measurements are then used in our optical modelling software (ZEMAX) to create accurate models of the scanned lenses and also to assess their optical efficacy. This project requires basic understanding of ocular physiology, optics and computer modelling.
Areas of expertise
- Physiological Optics
- Non-invasive ocular imaging
- Computational modelling of the eye tissue
Selected publications and creative works (Research Outputs)
- Muir, E. R., Pan, X., Donaldson, P. J., Vaghefi, E., Jiang, Z., Sellitto, C., & White, T. W. (2020). Multi-parametric MRI of the physiology and optics of the in-vivo mouse lens. Magnetic resonance imaging, 70, 145-154. 10.1016/j.mri.2020.04.015
Other University of Auckland co-authors: Wilson Pan, Paul Donaldson
- Thakur, S. S., Pan, X., Kumarasinghe, G. L., Yin, N., Pontre, B. P., Vaghefi, E., & Rupenthal, I. D. (2020). Relationship between rheological properties and transverse relaxation time (T2) of artificial and porcine vitreous humour. Experimental Eye Research, 19410.1016/j.exer.2020.108006
Other University of Auckland co-authors: Sachin Thakur, Wilson Pan, Beau Pontre, Ilva Rupenthal
- Vaghefi, E., Hill, S., Kersten, H. M., & Squirrell, D. (2020). Quantification of Optical Coherence Tomography Angiography in Age and Age-Related Macular Degeneration Using Vessel Density Analysis. Asia-Pacific journal of ophthalmology (Philadelphia, Pa.), 9 (2), 137-143. 10.1097/apo.0000000000000278
Other University of Auckland co-authors: Hannah Kersten
- Vaghefi, E., Hill, S., Kersten, H. M., & Squirrell, D. (2020). Multimodal Retinal Image Analysis via Deep Learning for the Diagnosis of Intermediate Dry Age-Related Macular Degeneration: A Feasibility Study. JOURNAL OF OPHTHALMOLOGY, 202010.1155/2020/7493419
Other University of Auckland co-authors: Hannah Kersten
- Xie, L., Yang, S., Squirrell, D., & Vaghefi, E. (2020). Towards implementation of AI in New Zealand national diabetic screening program: Cloud-based, robust, and bespoke. PloS one, 15 (4)10.1371/journal.pone.0225015
Other University of Auckland co-authors: Song Yang
- Hill, S., Vaghefi, E., Kersten, H., & Squirrell, D. (2019). Multi-input artificial intelligence design for multi-modal retinal imaging diagnosis of intermediate dry age related macular degeneration. CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY. (pp. 2).
- Squirrell, D., Hill, S., Song, E., Xie, L., Alshaikhi, M., & Vaghefi, E. (2019). Primary grading of diabetic retinopathy from retinal images using a custom designed CNN: The Auckland experience. CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY. (pp. 1).
- Hill, S., Mullins, P., Schmiedel, O., Alshaikhi, M., Vaghefi, E., & Squirrell, D. (2019). Epidemiology of diabetic retinopathy and maculopathy in Auckland, New Zealand: a regional photo-screening program 2006-2018. CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY. (pp. 1).