Session: Session 4

Towards in-man SpiderMass Mass Spectrometry Imaging for clinical surgery

Tumour cells infiltrate nearby healthy tissues. Surgeons must thus excise the peritumoral area to avoid patient relapses. The assessment of tumour margins is crucial for the patient’s prognosis, yet difficult to perform owing to the lack of visual distinction between margins and healthy tissue. Intraoperative evaluation tools are however limited in either speed (imaging...) or quality (histopathological assays...). The SpiderMass system is envisioned as a minimally invasive method to provide in-man intraoperative margin assessment through WALDI-MSI, but improvements are needed before it becomes viable in this context. We propose developments in data acquisition and processing to make it so.

WALDI-MSI is performed through the SpiderMass system in its imaging setup. Briefly, a laser impacts the tissue, creating ions by exciting endogenous water molecules. They are then vacuumed into a spectrometer for analysis. This setup foregoes sample preparation.

MSI experiments have been realized on a variety of 2D and 3D samples including beef liver, chicken breast, rat brain and mice affected with breast cancer. The data was then exported to a common 3D file format, allowing for visualization improvements, including the use of a perceptually linear colour space (OKLab), picture coregistration and better rendering through Blender, especially for topographical samples. Early AR results were achieved by overlaying the molecular data on top of a 3D scan of the sampling workspace. We have also implemented continuous imaging, netting 14 times faster images at the cost of lower intensities and a potential offset of molecular information, opening new avenues for a surgery.

Those results will be the basis of further research, including refinements of the handpiece and fiber, as well as the use of additional 3D sensing cameras for better spatial coverage in AR. We are also working on implementing a soft robot that could enable the SpiderMass to be used in minimally invasive surgeries.