Figure 2

Frozen tissue analysis using HCA spectroscopic imaging & supervised pattern recognition. (a) H&E stained image of a positive lymph node PN1. The positive node comprises large regions of cancerous breast tissue (4), remnants of healthy cortex tissue (2), and collagenous tissues such as the capsule (1) and medullary sinuses (3), respectively. (b) HCA spectroscopic image of positive lymph node PN1. The IR imaged area (2.8 mm × 7.5 mm) was mapped using a step size and aperture of 25 μm for a total 33,600 individual IR spectra. The red colour in the image describes areas of cancerous invasion, whereas the blue colour depicts a region of remnant healthy cortex tissue. Green, grey and cyan colours in the image represent regions of collagen containing tissues such as the capsule, medullary cords and sinuses, respectively. (c) ANN image of positive lymph node PN1. The red colour in the image describes regions classified as cancerous by the analysis. In contrast, the blue colour depicts the tissue that was correctly classified as non-cancerous. Black pixels within the image describe spectra that were not able to be classified by the neural net.