What is the interpretation of bladder ultrasound scan results?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 16, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Bladder scan results should be interpreted with caution, considering the patient's medical history, symptoms, and complete clinical picture, as a single reading may not accurately indicate pathology. When interpreting bladder scan results, it is essential to consider the post-void residual (PVR) volume, which can indicate incomplete bladder emptying if elevated. According to general guidelines, a PVR volume less than 50 mL is considered normal, while volumes greater than 100-200 mL may indicate incomplete bladder emptying 1.

Key Considerations for Interpretation

  • Provide the healthcare provider with a complete medical history, current medications, and any urinary symptoms being experienced.
  • Bladder scans use ultrasound technology to measure remaining urine after voiding, helping diagnose conditions like urinary obstruction, neurogenic bladder, or detrusor muscle dysfunction.
  • Results must be considered alongside symptoms and medical history, as a single elevated reading may not necessarily indicate pathology.

Potential Treatment Options

  • If urinary retention is diagnosed, treatment might include medications like tamsulosin 0.4 mg daily for men with prostatic obstruction, or bethanechol 10-50 mg three times daily to improve bladder contractility.
  • Intermittent catheterization may be necessary in some cases.
  • Proper hydration and timed voiding can also help manage mild retention. It is crucial to approach bladder scan results with a comprehensive understanding of the patient's clinical context, as recommended by guidelines from reputable organizations such as the American College of Physicians 1.

From the Research

Bladder Scan Results Interpretation

Bladder scan results are used to assess the amount of urine left in the bladder after voiding, known as post-void residual (PVR) volume. The interpretation of these results is crucial in diagnosing and managing urinary retention.

  • A PVR volume greater than 300 mL measured on two separate occasions and persisting for at least six months is defined as chronic urinary retention by the American Urological Association 2.
  • The measurement of PVR volume is an essential part of the initial evaluation of urinary retention, along with a detailed history and focused physical examination with neurologic evaluation 2.
  • Bladder ultrasonography can be used to measure PVR volume and reduce the rate of bladder damage and urinary tract infections 3.

Causes of Urinary Retention

Urinary retention can be caused by various factors, including:

  • Obstructive causes, such as benign prostatic hyperplasia, which accounts for 53% of cases in men 2.
  • Infectious, inflammatory, iatrogenic, and neurologic causes can also affect urinary retention 2, 4.
  • The etiology of acute urinary retention can be varied and multifactorial, and treatment aims to relieve the obstruction and mitigate the underlying cause of retention 4.

Management of Urinary Retention

The management of urinary retention involves:

  • Assessment of urethral patency with prompt and complete bladder decompression by catheterization 2.
  • Suprapubic catheters can improve patient comfort and decrease bacteriuria and the need for recatheterization in the short term 2.
  • Further management is decided by determining the cause and chronicity of the urinary retention and can include initiation of alpha blockers with voiding trials 2.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Urinary Retention.

Emergency medicine clinics of North America, 2019

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.