TY - JOUR
T1 - Microcamera Visualisation System to Overcome Specular Reflections for Tissue Imaging
AU - Niemitz, Lorenzo
AU - van der Stel, Stefan D.
AU - Sorensen, Simon
AU - Messina, Walter
AU - Venkata Sekar, Sanathana Konugolu
AU - Sterenborg, Henricus J. C. M.
AU - Andersson-Engels, Stefan
AU - Ruers, Theo J. M.
AU - Burke, Ray
N1 - Funding Information: This research was funded by Science Foundation Ireland Grant SFI-12/RC/2276_P2 and SFI-15/RP/2828. Publisher Copyright: © 2023 by the authors.
PY - 2023/5/1
Y1 - 2023/5/1
N2 - In vivo tissue imaging is an essential tool for medical diagnosis, surgical guidance, and treatment. However, specular reflections caused by glossy tissue surfaces can significantly degrade image quality and hinder the accuracy of imaging systems. In this work, we further the miniaturisation of specular reflection reduction techniques using micro cameras, which have the potential to act as intra-operative supportive tools for clinicians. In order to remove these specular reflections, two small form factor camera probes, handheld at 10 mm footprint and miniaturisable to 2.3 mm, are developed using different modalities, with line-of-sight to further miniaturisation. (1) The sample is illuminated via multi-flash technique from four different positions, causing a shift in reflections which are then filtered out in a post-processing image reconstruction step. (2) The cross-polarisation technique integrates orthogonal polarisers onto the tip of the illumination fibres and camera, respectively, to filter out the polarisation maintaining reflections. These form part of a portable imaging system that is capable of rapid image acquisition using different illumination wavelengths, and employs techniques that lend themselves well to further footprint reduction. We demonstrate the efficacy of the proposed system with validating experiments on tissue-mimicking phantoms with high surface reflection, as well as on excised human breast tissue. We show that both methods can provide clear and detailed images of tissue structures along with the effective removal of distortion or artefacts caused by specular reflections. Our results suggest that the proposed system can improve the image quality of miniature in vivo tissue imaging systems and reveal underlying feature information at depth, for both human and machine observers, leading to better diagnosis and treatment outcomes.
AB - In vivo tissue imaging is an essential tool for medical diagnosis, surgical guidance, and treatment. However, specular reflections caused by glossy tissue surfaces can significantly degrade image quality and hinder the accuracy of imaging systems. In this work, we further the miniaturisation of specular reflection reduction techniques using micro cameras, which have the potential to act as intra-operative supportive tools for clinicians. In order to remove these specular reflections, two small form factor camera probes, handheld at 10 mm footprint and miniaturisable to 2.3 mm, are developed using different modalities, with line-of-sight to further miniaturisation. (1) The sample is illuminated via multi-flash technique from four different positions, causing a shift in reflections which are then filtered out in a post-processing image reconstruction step. (2) The cross-polarisation technique integrates orthogonal polarisers onto the tip of the illumination fibres and camera, respectively, to filter out the polarisation maintaining reflections. These form part of a portable imaging system that is capable of rapid image acquisition using different illumination wavelengths, and employs techniques that lend themselves well to further footprint reduction. We demonstrate the efficacy of the proposed system with validating experiments on tissue-mimicking phantoms with high surface reflection, as well as on excised human breast tissue. We show that both methods can provide clear and detailed images of tissue structures along with the effective removal of distortion or artefacts caused by specular reflections. Our results suggest that the proposed system can improve the image quality of miniature in vivo tissue imaging systems and reveal underlying feature information at depth, for both human and machine observers, leading to better diagnosis and treatment outcomes.
KW - cross polarisation
KW - endoscopy
KW - imaging
KW - micro cameras
KW - multi-flash
KW - specular reflection
KW - surgical guidance
UR - http://www.scopus.com/inward/record.url?scp=85160614122&partnerID=8YFLogxK
U2 - https://doi.org/10.3390/mi14051062
DO - https://doi.org/10.3390/mi14051062
M3 - Article
C2 - 37241685
SN - 2072-666X
VL - 14
JO - MICROMACHINES
JF - MICROMACHINES
IS - 5
M1 - 1062
ER -