Abstract: An ultrasonic probe assembly comprises a housing defining a longitudinal axis and having a linear motor assembly, a swivel base, and an extension arm disposed therewithin. An imaging transducer is mounted on a free end of the extension arm and is specifically adapted to be moved along an arcuate path as a result of mechanical interconnection of the swivel base to the linear motor assembly. The swivel base upon which the extension arm is mounted is configured to be pivotable about a pivot axis oriented transversely relative to the longitudinal axis such that reciprocative motion of the linear motor assembly is converted in swiveling motion of the swivel base and oscillating translation of the transducer along an arcuate path such that the transducer axis is oriented generally perpendicularly relative to an anatomical structure having a convexly shaped outer surface.