Analysis of live beings is facilitated. According to an example embodiment of the present invention, a light-directing arrangement such as an endoscope is mounted to a live being. Optics in the light-directing arrangement are implemented to pass source light (e.g., laser excitation light) into the live being, and to pass light from the live being for detection thereof. The light from the live being may include, for example, photons emitted in response to the laser excitation light (i.e., fluoresced). The detected light is then used to detect a characteristic of the live being.