An imaging probe for use in a catheter for ultrasonic imaging is provided. The catheter may be of the type including a sheath having an opening at a distal end for conducting a fluid there through. The imaging probe includes a distal housing coupled to a drive shaft for rotation, a transducer within the distal housing for generating and sensing ultrasonic waves, and a fluid flow promoter that promotes flow of the fluid within the sheath across the transducer.