Management of Pelvic Phleboliths
Pelvic phleboliths require no treatment, as they are benign calcifications in pelvic veins that are clinically insignificant incidental findings.
What Are Pelvic Phleboliths?
Pelvic phleboliths are focal calcifications within pelvic veins, composed of calcified laminated fibrous tissue with a surface layer continuous with vein endothelium 1. They are extremely common, occurring in approximately 38.9%-48% of adults, with increased prevalence in individuals over age 40 1. These calcifications affect both genders equally and are more frequently observed in economically developed countries 1.
Clinical Significance
Phleboliths are generally considered harmless and do not require any intervention 2, 1. While rare case reports have documented associations with pelvic vein thrombosis, these represent exceptional circumstances rather than typical clinical scenarios 2. The primary clinical relevance of phleboliths is their potential to cause diagnostic confusion rather than any direct pathological effect.
Key Diagnostic Challenge: Distinguishing from Ureteral Calculi
The main clinical importance of recognizing phleboliths is avoiding misdiagnosis, particularly when attempting to differentiate them from ureteral stones on imaging studies 3, 1.
Radiological Features Suggesting Phleboliths (Not Stones):
- Central lucency: 8%-60% sensitivity, 100% specificity 1
- Rounded shape: 91% positive predictive value 1
- Comet-tail sign: 21%-65% sensitivity, 100% specificity 1
- Lower Hounsfield units: 160-350 HU (significantly lower than ureteral calculi) 1
Radiological Features Suggesting Ureteral Calculi (Not Phleboliths):
- Soft-tissue rim sign: 50%-77% sensitivity, 92%-100% specificity 1
- Geometric shape: 100% positive predictive value 1
Common Pitfall to Avoid
Do not mistake phleboliths for malpositioned intrauterine devices or intraperitoneal foreign bodies 3. When IUD strings are missing and radiodensities are visible on plain radiographs, consider phleboliths in the differential diagnosis before proceeding to invasive procedures. Three-dimensional ultrasonography or CT imaging can definitively distinguish between these entities 3.
Management Algorithm
- Incidental finding on imaging: No follow-up or treatment needed
- Suspected ureteral calculus: Use CT characteristics above to differentiate; if phlebolith confirmed, reassure patient and document to prevent future confusion
- Multiple pelvic calcifications: Often phleboliths, especially if bilateral and near ureters 3
No surveillance imaging, medication, or intervention is indicated for pelvic phleboliths once the diagnosis is established 1.