Fig 1.
Clinical presentation and macroscopic aspect of cutaneous neurofibroma.
(A) Example of a 43-year-old male patient that underwent surgical removal of eleven neurofibromas on the trunk and extremities (not shown), nine of which were processed for spectral analysis. (B, C) Macroscopic aspect of representative surgical specimen measuring 3.7x1.8 cm from top and lateral view.
Fig 2.
Illustration of Raman spectral acquisition and processing.
Left panel: Sketch of self-engineered Raman probe as described in [20]. DM: dichroic mirror; L: lens; LP: long-pass filter; M: mirror; SP: short-pass filter; Right panel: Illustration of efficient extraction of Raman spectrum from extreme fluorescence interference and biological tissues classification.
Fig 3.
Distinction of neurofibroma from other physiological entities via Raman spectroscopy and PCA.
(A) Mean purified spectra of cutaneous neurofibroma, physiological skin, fat, nerve, bone and mucosa, and the assignment of the Raman peaks to their respective molecular origin is shown in rectangular colorized boxes. (B) PCA with scatter plot of the projections of the purified Raman spectra of cutaneous neurofibroma, as well as physiological skin, fat, nerve, bone, and mucosa onto the first three principal components.
Table 1.
Assignment of spectral features in the mean Raman spectrum to the molecular vibrations [18, 27–32].
Table 2.
Classification results of cutaneous neurofibroma against all physiological tissue.
The performance of the classification estimated based on sensitivity, specificity, overall accuracy and soon.
Fig 4.
Histology of cutaneous neurofibroma in the plane examined by Raman spectroscopy.
Left, cutaneous neurofibroma presenting as tumor with uniform cell density extending to the subepidermal tissue (bottom of the image). Note the defect set by the needle which was inserted to mark the plane examined by Raman spectroscopy. Hematoxylin & Eosin stain, scale bar 1 mm. Right, close-up of the framed area in the left picture depicting spindle shaped tumor cells with wavy contour and slender nuclei. Hematoxylin & Eosin stain, scale bar 200 μm.