The OTP, which uses fiber-optic fluorescence spectroscopy, generates fluorescence ratios to indicate healthy tissue and tumour tissue.

For the study, researchers from Linkoping University in Sweden evaluated OTP in nine patients undergoing standard resection for possible glioblastoma multiforme tumours, through white light microscopy and ultrasound-based navigation.

Study results showed that OTP successfully identified and differentiated healthy tissue from tumour tissue.

The fluorescence ratios obtained from the OTP showed that the ratio outside the tumour was zero, was low in the gliotic edema zone, high in the marginal zone, highest in the solid tumour tissue, and zero in the necrotic tissue in the tumour’s centre.

Researchers note that the OTP can be used in combination with ultrasound-based navigation, to determine whether to resect otherwise non-identifiable tissue.