Method and apparatus for two dimensional ultrasonic imaging

A non-real time ultrasonic imaging system the system comprising:

• a probe adapted for use on the exterior surface of the body and having an ultrasonic transducer, the transducer capable of imaging along a scanline, wherein the scanline is fixed in orientation and unmovable with respect to the probe wherein the transducer has at least one piezoelement capable of transmitting signals and receiving signals along the scanline;
• ultrasound electronics in communication with the probe, the ultrasound electronics transmitting signals and receiving signals from the probe;
• an electromagnetic positioning receiving sensor mechanically coupled to the probe;
• an electromagnetic positioning transmitter for transmitting probing magnetic fields to the positioning receiving sensor, wherein the transmitter is stationary relative to the freehand probe;
• means coupled to the electronics and the electromagnetic positioning receiving sensor for computing the spatial position and the orientation of at least one sampled scanline using position information from the sensor and transmitting the scanline orientation and spatial position to the electronics wherein the electronics identifies each scanline by a unique spatial address;
• a memory coupled to the electronics for storing the addressed scanlines;
• and
• a display coupled to the memory and electronics for displaying the addressed scanlines wherein the movement of the probe results in the accumulation of multiple spatial addressed scanlines displayable as an image in a scanplane.

A method of ultrasonically imaging a body, the method comprising the steps of:

• providing an untethered ultrasound transducer having a scanline of fixed unmoving orientation relative to the transducer, the transducer having an integrated spatial position sensor;
• placing the untethered ultrasound transducer on an exterior body surface of a patient;
• operating the untethered transducer;
• receiving at least one scanline of ultrasound data from the transducer;
• addressing the at least one scanline with a spatial position and orientation of the transducer wherein the spatial position sensor provides the spatial position and orientation;
• receiving a plurality of scanlines of ultrasound data from a plurality of transducer positions, addressing each scanline of ultrasound data with a unique spatial position and orientation and reporting the unique spatial positions and orientations to ultrasound electronics and display an image formed by the scanline;
• and
• displaying an image composed of multiple such scanlines as a two dimensional image.