Transrectal Ultrasonography – An Overview
Transrectal ultrasonography is the latest form of ultrasonic examination. Similar to intravaginal, transurethral and transesophageal ultrasound, it utilizes a special transducer that is introduced into the rectum for medical examination of the adnexal organs, the most important of which is the prostate.
Transrectal ultrasonography is not a non-invasive procedure. Since it involves inserting the probe into the rectum, patients might feel mild discomfort. Adequate lubrication and gentle insertion usually alleviate and reduce the problem. The three types of transducers used for transrectal ultrasonography are the radial tomographic type, the linear type and the modifiable axis type. Among these, the tomographic type is the most popular. The latest one being used is the modifiable axis type. The former type gives transverse sections of tissues at right angles to its long axis whereas the linear type gives longitudinal sections of the structures at one side of its long axis. The complete examination is done by advancing and retreating the transducer probe.
During the test, the patient is instructed to lie in the lateral position, usually left. The after lubrication, the probe can be introduced into the rectum just like doing digital examination. Sedation is not generally given to our patients. Initially, the urethra, prostate, and bladder sequentially are examined, and then prostate measurements are made. The other structures can also be examined by rotating the probe. For proper bladder and upper prostate examination, bladder distension is required, that is the patient is required to hold urine for 3 to 4 hours for capturing good images.