In-vivo NIR autofluorescence imaging of rat mammary tumors

University of California, San Francisco, San Francisco, California, United States
Optics Express (Impact Factor: 3.53). 08/2006; 14(15):6713-23. DOI: 10.1364/OE.14.006713
Source: PubMed

ABSTRACT We investigate in vivo detection of mammary tumors in a rat model using autofluorescence imaging in the red and far-red spectral regions. The objective was to explore this method for non-invasive detection of malignant tumors and correlation between autofluorescence properties of tumors and their pathologic status. Eighteen tumor-bearing rats, bearing eight benign and seventeen malignant tumors were imaged. Autofluorescence images were acquired using spectral windows centered at 700-nm, 750-nm and 800-nm under laser excitation at 632.8-nm and 670- nm. Intensity in the autofluorescence images of malignant tumors under 670-nm excitation was higher than that of the adjacent normal tissue. whereas intensity of benign tumors was lower compared to normal tissue.

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