A finger-mounted probe is under development at the University of Western Australia to improve the surgical removal of breast cancer. This approach could be of value in scenarios where the use of a relatively bulky handheld probe is not convenient, such as when assessing if residual tumor is present in small cavities following excision of the main tumor mass in breast-conserving surgery. The device might also prove useful for brain and liver surgery and other types of cancer.
A fiber probe incorporated into a wearable thimble uses quantitative micro-elastography (QME) to translate the sense of touch into high-resolution images. The system uses measurements from optical coherence tomography (OCT), which generates high-resolution, depth-resolved images of tissue structure by measuring the reflections of light.
The probe is pressed perpendicularly into the tissue while OCT images are recorded, combining medical imaging with mechanical deformation to map tissue elasticity and detect microscale changes in stiffness, which are indicative of disease.
Tests on silicone phantoms designed to simulate healthy and diseased tissues in the breast tests showed an 87% accuracy for the finger-mounted probe, slightly lower than a conventional benchtop QME system but sufficiently high for potential clinical use. Analyses also documented a sixfold increase in stiffness of a kangaroo muscle sample following heating. A 2D image obtained by scanning the probe laterally across a silicone phantom containing a stiff inclusion revealed lower accuracy than the experiment performed without scanning. However, the researchers maintain that the prospect for imaging by swiping the operator's finger is very encouraging.
Efforts now focus on embedding the optical components of the probe into a surgical glove that would preserve the touch sensitivity and dexterity of manual palpation, and on improving the accuracy of 2D scanning. The study is published in Biomedical Optics Express.