An apparatus configured for emitting broadband light obtained from a light source onto a tissue and receives interacted light that is obtained from interaction of the broadband light with the tissue, comprising: a probe, the probe including: an end adapted for insertion into the human body; a delivery optical fiber having a delivery numerical aperture for transmitting the broadband light obtained from a light source, the light delivery optical fiber having a light delivery end adapted for emission of the broadband light and a source connection end adapted for connection to the light source; at least one collection optical fiber having a collection numerical aperture, the collection optical fiber having a light collection end that receives the interacted light and a receiver connection end, wherein the light collection end is substantially aligned with and at a predetermined distance from the light delivery end of the delivery optical fiber; a lens that is spaced substantially about one focal length of the lens from the light collection end of the collection optical fiber and from the light delivery end of the delivery optical fiber and, a receiver coupled to the at least one collection optical fiber at the receiver connection end, and adapted for estimating a characteristic indicative of at least blood content or blood flow in the at least one of mucosal and submucosal tissue based on the received interacted light; and an indicator electrically coupled to said receiver and adapted for providing an indication based on said estimated characteristic; characterized in that said indicator is adapted for providing the indication of the presence of increased blood supply in the illuminated target tissue based on a comparison with a prior measurement of another region of the at least one of mucosal and submucosal tissue. a probe, the probe including: an end adapted for insertion into the human body; a delivery optical fiber having a delivery numerical aperture for transmitting the broadband light obtained from a light source, the light delivery optical fiber having a light delivery end adapted for emission of the broadband light and a source connection end adapted for connection to the light source; at least one collection optical fiber having a collection numerical aperture, the collection optical fiber having a light collection end that receives the interacted light and a receiver connection end, wherein the light collection end is substantially aligned with and at a predetermined distance from the light delivery end of the delivery optical fiber; a lens that is spaced substantially about one focal length of the lens from the light collection end of the collection optical fiber and from the light delivery end of the delivery optical fiber and, an end adapted for insertion into the human body; a delivery optical fiber having a delivery numerical aperture for transmitting the broadband light obtained from a light source, the light delivery optical fiber having a light delivery end adapted for emission of the broadband light and a source connection end adapted for connection to the light source; at least one collection optical fiber having a collection numerical aperture, the collection optical fiber having a light collection end that receives the interacted light and a receiver connection end, wherein the light collection end is substantially aligned with and at a predetermined distance from the light delivery end of the delivery optical fiber; a lens that is spaced substantially about one focal length of the lens from the light collection end of the collection optical fiber and from the light delivery end of the delivery optical fiber and, a receiver coupled to the at least one collection optical fiber at the receiver connection end, and adapted for estimating a characteristic indicative of at least blood content or blood flow in the at least one of mucosal and submucosal tissue based on the received interacted light; and an indicator electrically coupled to said receiver and adapted for providing an indication based on said estimated characteristic; characterized in that said indicator is adapted for providing the indication of the presence of increased blood supply in the illuminated target tissue based on a comparison with a prior measurement of another region of the at least one of mucosal and submucosal tissue. an indicator electrically coupled to said receiver and adapted for providing an indication based on said estimated characteristic; characterized in that said indicator is adapted for providing the indication of the presence of increased blood supply in the illuminated target tissue based on a comparison with a prior measurement of another region of the at least one of mucosal and submucosal tissue.