Imaging system based on diffusive reflectance spectroscopy for blood vessels detection during brain biopsy procedure

During the diagnosis and treatment process for brain cancer, clinicians often need to achieve a brain biopsy to get histological data. However there are risks associated with this procedure: 1) collected samples are not always representative of the tumor and 2) there is a risk of blood vessel rupture when the sample is taken. This type of bleeding occurs between 0.3 and 59.8% of the cases and the mortality rate can be as high as 3.9% (Dammers et al, Woodworth et al). Here we present a diffuse reflectance spectroscopy imaging system directly integrated on a brain biopsy needle to guide surgeon during needle biopsy procedures. To mitigate the risks associated with the procedure, our imaging system combines 18 optical fibers (9 used as white-light sources and 9 used as detectors) to acquire a total of 81 reflectance spectra per acquisition. A tomographic algorithm (Goyette et al) is used to reconstruct an image in the vicinity of the needle based on the optical contrast due to the optical absorption of hemoglobin (Hb) which is the main absorber in brain. The evaluation and characterization tests were first carried out in vitro using tissue-simulating phantoms reproducing human brain optical properties (absorption and scattering).