Ultrasound Appearance of Prostatitis
On ultrasound, prostatitis typically appears as an enlarged, hypoechoic gland with increased vascularity, heterogeneous echotexture, and potential periurethral hypoechoic zones. 1
Key Ultrasound Findings in Prostatitis
General Appearance
- Enlarged prostate gland - Often the most obvious finding
- Heterogeneous echotexture - Irregular appearance compared to normal homogeneous pattern
- Hypoechoic areas - Focal or diffuse regions of decreased echogenicity
- Increased vascularity - Visible on Doppler ultrasound examination
- Periurethral hypoechoic zone - Present in up to 97% of chronic prostatitis patients 2
Specific Findings by Type of Prostatitis
Acute Bacterial Prostatitis
- Markedly enlarged, edematous gland
- Significantly hypoechoic areas representing edema or microabscesses
- Pronounced hypervascularity on Doppler imaging
- Potential prostatic abscesses appearing as well-defined anechoic or hypoechoic areas 1
Chronic Bacterial Prostatitis
- More subtle enlargement than acute prostatitis
- Heterogeneous echotexture
- Prostatic calcifications (more common in chronic cases) 3
- Hypoechoic periurethral zone volume correlating with symptom severity 2
Diagnostic Value and Limitations
Transrectal ultrasound (TRUS) is valuable for:
- Guiding prostate biopsies
- Evaluating prostate shape, size, and configuration
- Assessing for prostatic abscess formation in acute prostatitis 1
- Differentiating prostatitis from other conditions
However, ultrasound has limitations:
- Cannot definitively distinguish prostatitis from prostate cancer in all cases
- Advanced ultrasound techniques for differentiation between prostate cancer and prostatitis are still under evaluation 1
- Not routinely necessary for initial diagnosis of uncomplicated prostatitis
Clinical Correlation
The severity of ultrasound findings often correlates with clinical symptoms:
- Patients with prostatic calcifications show more severe symptom burden in chronic bacterial prostatitis 3
- Hypoechoic periurethral zone volume independently predicts worse pain and urinary symptoms 2
- Posterior prostate lip thickness correlates with urinary symptoms 2
Recommendations for Use
- Transrectal ultrasound should be performed in selected cases to rule out prostatic abscess in acute bacterial prostatitis 1
- Not routinely necessary for initial diagnosis of uncomplicated prostatitis
- Consider TRUS when symptoms persist despite appropriate antibiotic therapy
- Particularly valuable when planning interventional therapies or when anatomical features may impact treatment choice 1
Common Pitfalls
- Mistaking prostatitis for prostate cancer (both can appear hypoechoic)
- Overlooking small prostatic abscesses that require drainage
- Failing to use Doppler to assess vascularity (helpful diagnostic feature)
- Not correlating ultrasound findings with clinical presentation and laboratory results
By combining ultrasound findings with clinical presentation and laboratory tests, clinicians can more accurately diagnose prostatitis and monitor treatment response.