Photo of Dr Riaz Akhtar

Dr Riaz Akhtar MEng, PhD, SFHEA, FIMMM

Senior Lecturer in Biomedical Engineering Mechanical, Materials & Aerospace Eng

Research

Arterial Stiffening and Aortic Dissection

 Length-scale dependent architecture within the mammalian aorta [Akhtar et al., Materials Today, 2011]
Length-scale dependent architecture within the mammalian aorta [Akhtar et al., Materials Today, 2011]

Arteries become stiffer with the natural ageing process and this stiffening which is associated with cardiovascular disease is exacerbated with conditions such as diabetes. For many years, I have had an interest in understanding how the structure and mechanical properties of large arteries is compromised at the microscopic and sub-microscopic level. Arteries are multi-layered anatomical structures with a complicated organisation of cells of cellular and extracellular matrix components within these layers. Hence, understanding how they change with ageing and disease processes is not trivial. I first focussed on this research area as a British Heart Foundation Advanced Training research fellow and have continued to build on this strand of research over the years. We have developed many novel approaches to characterise vascular tissue at these length scales. Such research is important for the development of mechanistic understanding of arterial disease and the development of new clinical treatments. Our current research in this area is in close collaboration with University of Southern Denmark in view to better relate nano-architecture and nanomechanical properties of arterial tissue with clinical markers.Review Paper: Characterizing the elastic properties of tissuesReview Paper: In vitro characterisation of arterial stiffening: From the macro- to the nano-scale

A main thrust of our research currently involves understanding rare aortic diseases such as Acute Type A aortic dissection (AAD). AAD involves a splitting in the aortic wall which is life-threatening and often occurs in young patients without any previous relevant medical history. We are using a range of novel techniques to try and better understand the risk of aortic dissection developing. We conduct this research with vascular surgeons at Liverpool Heart and Chest Hospital and also collaborators in a range of other disciplines such as biochemistry and mathematical modelling. Our funding for this research comes from a number of sources including British Heart Foundation.

Ocular Micromechanics

The eye is a fascinating organ of the human body. The cornea and sclera (white of the eye) exhibit interesting biomechanical behaviour, and common eye disorders such as myopia are associated with substantial biomechanical changes in the eye. Our research in to the nano- and micro-mechanical changes in ocular tissues with ageing and disease fits in to the wider ocular biomechanics research within the School of Engineering (led by Prof. Elsheikh). We currently have active projects focussing on better understanding degenerative changes in the sclera and the cornea. One of my research interests in ocular biomechanics is keratoconus, a progressive, degenerative disease that is now considered to be a major clinical problem worldwide, affecting up to 600 people per 100,000.

Below is a link to an article I wrote in 'The Conversation' about ocular biomechanics: Understanding the mechanics of the eye could help treat degenerative disease - The Conversation

Skin Micromechanics and Microneedle Technology

In vitro experimentation of microneedles with impact testing [Moronkeji et al., Journal of Controlled Release, 2016).
In vitro experimentation of microneedles with impact testing [Moronkeji et al., Journal of Controlled Release, 2016).

Skin is a highly complex organ of the human body that is vital for heat and water loss as well as preventing harmful material from entering the body. Although the mechanics of skin are widely studied, an emerging area is how skin responds at the micro-scale. Recent research has shown that skin exhibits a different mechanical response at different length scales. Our research is not only interested in understanding how skin responds when probed at the micro-scale but also how this response can be exploited for drug delivery and sensing applications using microneedles. Microneedles are arrays of sub-millimetre projections which can be used to painless delivery drugs and vaccines to the skin. Our experience in skin micromechanics has contributed to projects with industry to develop microneedle devices for a range of different applications.

Research Grants

Exploring the interplay between biochemical and biomechanical heterogeneity as a risk factor for acute Type A aortic dissection

BRITISH HEART FOUNDATION (UK)

July 2017 - July 2019

A novel approach to identifying risk of rare aortic diseases

ROYAL ACADEMY OF ENGINEERING (UK)

October 2017 - September 2018

Providing a rational basis for the development of an injectable stem cell therapy for the treatment of osteoarthritis in ageing patients.

DUNHILL MEDICAL TRUST (UK)

February 2017 - February 2020

Micromechanical Properties of Sclerodermal Skin’

ROYAL SOCIETY (CHARITABLE)

March 2014 - November 2014

Impact Acceleration Account - University of Liverpool 2012

ENGINEERING & PHYSICAL SCIENCES RESEARCH COUNCIL (EPSRC)

October 2012 - March 2017

Clinical Data Collection for Refractive Surgery (LASIK)

THE ACADEMY OF MEDICAL SCIENCES (UK)

May 2012 - July 2014

Control of Biological Responses by Isolated Synthetic Material Variables.

LEVERHULME TRUST (UK)

April 2015 - October 2018

Small items of Research Equipment at the University of Liverpool

ENGINEERING & PHYSICAL SCIENCES RESEARCH COUNCIL (EPSRC)

November 2012 - March 2013

Research Collaborations

Mr Mark Field

Project: Aortic Dissection
External: Liverpool Heart and Chest Hospital

Mr Field is a vascular surgeon at Liverpool Heart and Chest Hospital. His clinical/surgical input is key into our various projects related to aortic dissection.

Dr Jill Madine

Project: Aortic Dissection
Internal

We work together on aortic dissection projects which involve biochemical expert input from Dr Madine.

Prof. Dave Adams

Project: Nanoindentation of Hydrogels
External: University of Glasgow

We work with Prof. Adam's research group to characterise low molecular weight gelators (LMWGs) with nanoindentation. This collaboration has led to several papers including in RSC Advances and Materials Chemistry.

Prof. Brian Derby

Project: Soft tissue micromechanics
External: The University of Manchester

We have worked on various projects relating to the development of nanoindentation and scanning acoustic microscopy (SAM) of soft tissues. We started this work when I was a postdoc in Prof. Derby's group.

Drs David Martin and Steve Barrett

Project: AFM imaging
Internal

We have worked together on a number of projects relating to atomic force microscopy (AFM) imaging of soft tissues. Dr Barrett's software, Image SXM, is used in a number of our publications for custom image analysis.

Dr Michael Sherratt

Project: Soft tissue micromechanics and biochemistry
External: The University of Manchester

We have worked on various projects relating to soft tissue micromechanics. In particular, Dr Sheratt's expertise on fibrillin microfibrils formed a key part of a large piece of work on the diabetic aorta.