PROSTATE ULTRASOUND IMAGING
WHY IS THE PROCEDURE PERFORMED?
Used to diagnose the most common disease to affect the prostate which are
Benign prostatic hypertrophy BPH
Prostatic cancer
Prostatitis
Prostate abscess
Seminal vesicle cyst
Prostate cyst
Infertility
THE PROCEDURE ITSELF
It is a transrectal ultrasound, so the patient lies on his side with his knees bent. A disposable protective cover is placed over the transducer, it is lubricated, inserted through the anus and placed into the rectum.
The images are obtained from different angles to get the best view of the prostate gland.
LENGTH OF THE EXAM
About 20 minutes.
BASICS
BENIGN PROSTATIC HYPERTROPHY
Due to diminished androgen secretion, the transitional and central zones of the prostate undergo hypertrophy, resulting in an increase in fibromuscular stroma. This enlargement obstructs the outflow of urine by compressing the prostatic urethra. Symptoms are a poor urinary stream and frequent urination. Hydronephrosis may occur secondary to urethral obstruction. Ultrasound in this case is used to determine:
the size of the prostate, which determines in turn the type of treatment.
the amount of post void residual urine in the bladder.
the presence of hydronephrosis.
PROSTATE CANCER
Is the second most common cancer in American men. More than 70% of prostate cancers are diagnosed in men over 75years of age. Prostate-specific antigen PSA is a blood test that is usually elected in the presence of prostate cancer, but also may be elevated by BPH or prosatitis. Symptoms include painful or difficult urination.
Ultrasound can be used to:
identify the presence of a prostatic mass.
attempt to stage periphrastic spread
guide radiotherapy treatment
PROSTATITIS
Inflammation of infection of the prostate gland, usually acute, chronic or noninfectious. Acute and chronic are infectious and treated by antibiotics. Noninfectious causes are not fully known but may include mechanical or chemical trauma, or an autoimmune process. The role of ultrasound in acute cases is limited. In many cases, the patient is not able to tolerate the secondary pain of the transrectal ultrasound.
PROSTATE ABSCESS
Can develop secondary to acute prostatitis, however are rare. When present, an anechoic area can be seen within the central zone that may contain low-level echoes.
SEMINAL VESICLE CYST
Result of inflammation of obstruction of the seminal vesicles or are remnants of the Mullerian duct.
PROSTATE CYST
May be Mullerian duct cysts, utricle cysts, prostatic retention cysts, ejaculatory duct cysts.
INFERTILITY
May be caused by blockage of the ejaculatory ducts or congenital absence of the seminal vesicles and vas deferens. Transrectal ultrasound can show the cause of ejaculatory duct obstruction, a cyst calcification, dilation of the ejaculatory ducts, or dilation of the seminal vesicles.
Sources:
Clinical sonography, Roger C. Sanders, Tom C. Winter