What Is Transrectal Ultrasound (TRUS)

Transrectal ultrasound (TRUS) is a diagnostic imaging procedure that uses high-frequency sound waves to produce detailed images of the prostate gland, seminal vesicles, and surrounding structures through a probe inserted into the rectum. It is a safe, minimally invasive test that does not involve radiation.

Purpose

  • Evaluate the prostate gland for enlargement, tumors, or abnormalities
  • Assist in diagnosing causes of male infertility, such as ejaculatory duct obstruction
  • Guide needle placement for prostate biopsy
  • Assess prostate and seminal vesicle anatomy before certain fertility treatments

What It Evaluates

  • Prostate size and shape – Detects enlargement (benign prostatic hyperplasia) or asymmetry
  • Structural abnormalities – Such as cysts, calcifications, or blockages in the ejaculatory ducts
  • Seminal vesicles – Check for dilation, inflammation, or obstruction
  • Signs of infection or inflammation – Prostatitis or vesiculitis

Procedure

  1. The patient lies on their side with knees bent toward the chest.
  2. A protective cover and lubricating gel are applied to the ultrasound probe.
  3. The probe is gently inserted into the rectum to obtain images of the prostate and seminal vesicles.
  4. The scan typically takes 10–20 minutes and may cause mild pressure or discomfort, but is generally well-tolerated.

Preparation Tips

  • A bowel preparation (such as an enema) may be recommended before the test.
  • You may be asked to empty your bladder before the procedure.

Possible Next Steps

  • If abnormalities are detected, your doctor may recommend additional testing such as hormone evaluation, semen analysis, MRI, or surgical intervention.
  • For suspected obstruction, corrective procedures may be considered to improve fertility potential.