Micro cameras as adjunct tools in biomedical applications

Biomedical imaging is one of the most impactful periprocedural tools and is used across a wide range medical applications. The eyes of the clinician are a key component in surgical decision making, and an image is often the first step in both diagnostic and interventional procedures. With the miniaturisation of CMOS image sensors, micro-cameras are being investigated for use in biomedical imaging and the development of biomedically specific sensors has begun. This thesis makes several important contributions to the use of these micro-cameras as adjunct tools that meet a number of unmet clinical needs in a variety of interventional procedures. To achieve this integration capabilities are demonstrated and a micro-camera based technology platform is developed. The micro-camera is integrated at the tip of various devices, along with multi-spectral fibre illumination, automated readout, control, and image processing; into a compact format suitable for clinical use. The technology is then applied to a number of applications, with the system tailored to the specific use cases. The verification of procedural success in a cardiovascular intervention is investigated. A micro-camera based 2.30 mm catheter device is developed and tested on an animal model. It is shown to be able to image in the challenging environment of the blood field. Here the procedure can be recorded and we are able to extract physiological information in a step toward verification of device placement as well as success of ablation procedures in the heart. The dimensions are pushed to 1.19 mm to navigate into the peripheral lung. This achieves imaging deeper than with a traditional bronchoscope, while maintaining the ability to provide multi-spectral illumination via fibre optics. This is demonstrated on ex-vivo tissue. The micro-camera platform makes an impact on breast conserving surgery procedures, where for the first time the periprocedural imaging of micro-calcifications is investigated. This enables the intra-surgical detection of micro-calcifications up to 2.00 mm in the resection margin. To do this a multi-spectral diffuse optical imaging technique for surgical guidance is proposed, and used to detect micro-calcifications. A rigorous co-registration method is developed to validate the data, and image processing techniques proposed to aid the automated detection. Finally, polarisation resolved imaging is investigated using the microcamera. Here the platform offers a solution for flexible polarisation resolved imaging systems. An initial prototype of both a miniature and benchtop system is presented along with images on optical elements and bulk tissue samples. Line of sight to tissue imaging, and to investigate multi-spectral polarisation resolved imaging is discussed.

Grantor dc:publisher

University College Cork

Year dc:date.issued

2024

Author dc:creator

• Niemitz, Lorenzo

Advisors dc:contributor.advisor

• Andersson-Engels, Stefan
• Burke, Ray
• Sorensen, Simon Toft

• Micro camera
• Endoscopy
• Imaging
• CMOS image sensor
• Miniaturisation

Statement dc:rights

• © 2024, Lorenzo Niemitz.

Licence dc:rights.uri

• https://creativecommons.org/licenses/by/4.0/

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10468/16376

OAI identifier oai:identifier

oai:cora.ucc.ie:10468/16376