Patent ID: 7803103

Claim:
A method of positioning a device for local delivery of radiation to intraocular sub-retinal target tissue a pre-determined space relative to the target tissue comprising: providing a device comprising a cannula sized for insertion into an eye and having a proximal end and a distal end; a radiation-emitting source adapted to be located in the distal end of the cannula; and an ultrasound transducer located in the distal end of the cannula adapted to directionally emit ultrasonic radiation toward the target tissue; calibrating the ultrasound transducer in accordance with a predetermined spacing for the distal end of the cannula from the sub-retinal target tissue so as to generate a signal when the predetermined spacing is achieved; introducing the cannula into an eye through an access site on the eye; and moving the distal end of the cannula toward the sub-retinal target tissue until the signal generated by the ultrasound transducer is perceived by a user.