Understanding Transrectal Ultrasound (TRUS) Transducers

Doctors use transrectal sonography to produce images of the rectum and organs located relatively close to the rectum such as the prostate gland and bladder. The transducer is the probe which emits ultrasound waves and receives echoes of the waves. The echoes are transmitted to a processor for creation of an image of the examined structure.

Technical Details

• Transrectal sonogram transducers function in the same way as other sonogram transducers. Piezoelectric crystals interact with an electrical impulse and generate sound waves. The waves travel through tissue, and an echo or return wave is generated in degrees varying with the type of tissue encountered by the waves.

  Waves pass through some types of tissue which then produce little or no echo, while other tissue reflects the waves producing a significant echo. The transducer receives the echo and changes it to an electrical impulse, which then goes to a unit for conversion into an image.

Examination

• To conduct transrectal sonography, a technician lubricates the transducer and inserts it into the rectum. The technician positions the transducer so that sound waves contact and pass through or are echoed back from the examined area, and an image of the area forms.

Benefits

• Transrectal sonography is a safe method of examination. Because tissues are viewable in real time, it also allows for safer and more effective sample taking, for example in prostate biopsies.