Ultrasound Scoring for BPH
There is no single standardized ultrasound scoring system universally recommended by major guidelines for BPH, but transabdominal ultrasound assessment of intravesical prostatic protrusion (IPP) grading combined with prostate volume and post-void residual provides the most clinically useful anatomical staging approach. 1, 2, 3
Recommended Ultrasound Assessment Parameters
Intravesical Prostatic Protrusion (IPP) Grading
The most validated ultrasound-based classification uses IPP measured in the midsagittal plane on transabdominal ultrasound, graded 1-3: 4, 3
- Grade 1 (Low-grade IPP): Minimal protrusion into bladder
- Grade 2 (Moderate IPP): Moderate protrusion
- Grade 3 (High-grade IPP): Significant protrusion
IPP grade correlates better with bladder outlet obstruction than prostate volume alone and helps predict surgical outcomes. 3
Essential Measurements to Obtain
When performing transabdominal ultrasound for BPH evaluation, measure: 1, 2, 3
- Prostate volume: Normal is generally <20 mL; enlargement typically >30-40 mL 1, 3
- Post-void residual (PVR): Significant if >100 mL; large volumes (>350 mL) may herald disease progression 2
- IPP grade: As described above 4, 3
- Anatomical features: Presence of intravesical lobes that may impact therapy choice 1, 2
Clinical Staging Based on Ultrasound Findings
A practical staging system integrates ultrasound findings with symptoms: 4, 3
- Stage I: No bothersome symptoms (QOL <3) AND no significant obstruction (PVR <100 mL) → Observation appropriate 4
- Stage II: Bothersome symptoms (QOL ≥3) BUT no significant obstruction (PVR <100 mL) → Medical therapy first-line 4
- Stage III: Significant obstruction (PVR >100 mL persistently), regardless of symptoms → TURP should be offered 4
- Stage IV: Complications of BPH present → TURP strongly recommended 4
When Ultrasound Is Indicated
Appropriate Use
Transabdominal or transrectal ultrasound is appropriate when: 1, 2
- Patient has selected minimally invasive or surgical intervention (to guide therapy selection) 1, 2
- Determining candidacy for specific procedures (TUMT, TUNA require specific size/shape criteria) 1
- Assessing for intravesical lobes that impact surgical approach 1, 2
Not Routinely Required
Ultrasound is not necessary for: 1, 2
- Initial evaluation before watchful waiting 1, 2
- Starting medical therapy (PSA can serve as proxy for prostate volume) 1
- Determining "need for treatment" (symptoms and bother drive this decision) 1
Important Caveats
Prostate size alone does not determine treatment need. A man with a large prostate but minimal symptoms may not require intervention, while someone with moderate enlargement but severe bother may benefit from treatment. 1, 2
IPP measurement requires proper technique. The measurement must be obtained in the midsagittal plane on transabdominal ultrasound to be reliable. 3
PVR is not a contraindication to conservative management. Many patients maintain large residual volumes without developing urinary tract infections, renal insufficiency, or worsening symptoms. 2
Transrectal ultrasound is primarily reserved for: 1
- Prostate biopsy guidance when PSA is elevated
- Detailed anatomical assessment when transabdominal views are inadequate
The evidence shows that while formal ultrasound scoring systems exist in research settings, clinical practice relies more on integrating IPP grade, prostate volume, and PVR with symptom severity to stage disease and guide management decisions. 4, 3