Abstract: A multi-channel, near infrared (NIR) imaging system comprising one or more optical fiber bundles; and a transrectal NIR probe having an outer material, wherein the optical fiber bundle is integrated into the transrectal probe (an end-fire or a side-fire NIR probe). The outer material is preferably rubber-like silicon or made of two translucent materials exhibiting low viscosity and requires curing at room temperature. The transrectal NIR probe comprises a curvature to match the curvature of a human rectum and may have a circular or oval-shaped silicone holder. The imaging system further comprises a broad-band light source adapted to deliver light to the fiber channels, an optical switch box adapted to allow only one of the fiber channels to pass through at a time; and a multi-channel spectrometer to capture tomographic images of changes in HbO, HbT, light scattering patterns and hemodynamic response times from human prostate.