Patent ID: 7668587

Claim:
A method for targeting an invasive medical device or instrument toward a target location in a living subject, after a contrast agent is administered to the living subject so as to have achieved distribution and localization within the subject, comprising: (a) performing an invasive medical or surgical procedure upon the subject using a medical device or instrument; (b) illuminating the subject with ambient light and light from a light source, wherein a modified light is generated after interaction with and modification of the light by said contrast agent in vivo; (c) gating a time-gated light imager wherein said gating is performed such that the imager detects light substantially enriched in the modified light while substantially rejecting the ambient light; (d) detecting the modified light with said gated imager; (e) determining a present status of the medical device or instrument with respect to said target location based upon the detected modified light; and (f) generating an output signal in response to said determination.