An imaging guidewire for imaging tissues from inside a patient's body cavity. The imaging guidewire includes an elongated main body portion and an end portion. The end portion has a housing near to the guidewire's distal end, an ultrasonic beam emitting assembly having a pivotable part, and a...http://www.google.com.hk/patents/US5779643?utm_source=gb-gplus-share專利 US5779643 - Imaging guidewire with back and forth sweeping ultrasonic source
