Endoscopy

Capturing optical imaging data from the interactions of light with tissue has been challenged by the fact that photographic methods aim at replicating human vision, hence discard or scramble information beyond the three broadband colour channels of red, green and blue. Motivated by the need to better evaluate the vascular architecture and function in the earliest stages of cancer, we have developed several optical methods and enable more precise optical imaging in endoscopy, where imaging is performed directly at the site of interest, for example, in the gastrointestinal tract.

Hyperspectral imaging (HSI) records both wavelength resolved (spectral) and structural (imaging) data simultaneously. Light reflected from biological tissue shows a spectral response that is dependent on the tissue composition, so HSI holds substantial promise in distinguishing the earliest signs of cancer. In particular, the absorption of light by oxy- and deoxy-haemoglobin leads to differences in the response of pre-cursor lesions as well as cancer.

For effective clinical translation of hyperspectral imaging there is, however, a need for compact and cost-effective implementations of the technology that operate with high-throughput and in real-time. Until recently, these unmet needs have prevented the application of HSI in biomedical imaging.

In our laboratory, we are creating and integrating novel HSI cameras into  endoscopy systems, with potential applications in diagnostic and therapeutic imaging. We produce snapshot HSI systems based on custom multispectral filter arrays (see figure below) and line-scan systems using commercial, high resolution HSI solutions. Our diversity of approaches allow us to tailor appropriate solutions based on the particular unmet need in cancer. We prioritise translation of our innovations and have already conducted first-in-human clinical trials using these systems in both the UK and the USA to demonstrate the feasibility of our solutions in the context of early cancer detection and lesion characterisation in the gastrointestinal tract.

Example of our grayscale-to-color multispectral filter array fabrication method for production of custom multispectral imaging cameras.
Image taken from Williams et al (2019) ACS Photonics.

Lab Members:
Alexandru Grigoroiu, Dr James Joseph, Michaela Taylor-Williams, Dr Dale Waterhouse, Dr Calum Williams.

Collaborators:
Dr Massi di Pietro, Prof. Rebecca Fitzgerald (University of Cambridge, UK).

Prof. Liana Tsikitis, Prof. Sarah Diamond (OHSU, USA), Dr Lingjie Kong (Tsinghua University, China)