Pelvic phleboliths are small, calcified formations that develop within the veins of the pelvis. Often described as “vein stones,” they are typically round or oval, measuring 2 to 5 millimeters. They are generally harmless and do not usually indicate a serious underlying medical condition.
Understanding Pelvic Phleboliths
Pelvic phleboliths originate from small blood clots, or thrombi, that form inside a vein. Over time, calcium and other minerals accumulate, causing them to harden and calcify into a stone-like entity.
These formations are common, especially within the pelvic region where blood flow can sometimes be slower. They are frequently found in lower pelvic veins, including the internal iliac, uterine, ovarian, and vesical veins. Their prevalence increases significantly with age, affecting approximately 35% to 48% of adults over 40.
Do They Cause Symptoms
Pelvic phleboliths are asymptomatic, meaning they typically do not produce noticeable pain or discomfort. Individuals often remain unaware of their presence unless discovered during medical imaging for unrelated reasons. Their small size and stable position within the vein prevent them from interfering with normal bodily functions or causing irritation.
In rare instances, a large phlebolith or those associated with other venous conditions, such as varicose veins, might lead to mild, localized aching or soreness in the pelvic area. Varicose veins, characterized by enlarged and swollen veins, can sometimes be painful and may coincide with phleboliths. However, the phlebolith itself is seldom the direct source of significant pain.
How They Are Identified
Because pelvic phleboliths rarely cause symptoms, their discovery is incidental. They are frequently detected during imaging tests of the abdomen or pelvis conducted for different health concerns. Common diagnostic tools include X-rays, computed tomography (CT) scans, and magnetic resonance imaging (MRI).
On X-rays, phleboliths appear as small, rounded white or light-colored spots. CT scans also show them as dense, calcified structures. Radiologists identify these formations by their characteristic appearance and location within the pelvic veins, sometimes noting a “comet-tail sign,” a tapering soft-tissue mass adjacent to the calcification.
Differentiating From Other Conditions
Identifying pelvic phleboliths accurately is important, especially since they can resemble other conditions that require different medical attention. A common diagnostic challenge involves distinguishing them from kidney or ureteral stones, which are calculi that form in the urinary tract and can cause severe pain. Both types of calcifications appear similarly dense on imaging.
Medical professionals differentiate phleboliths from kidney stones by observing specific features on imaging scans. Kidney stones often present with a “soft-tissue rim sign,” indicating inflammation around the stone, which is absent with phleboliths. Phleboliths tend to be rounded, while kidney stones may have a more geometric shape. Advanced imaging techniques, such as unenhanced CT, and careful analysis of location and specific radiological signs assist in accurate diagnosis.