A phlebolith, which derives from the Latin roots "phlebo," meaning vein, and "lith," meaning stone, is a small stone in a vein formed by the accumulation of calcium deposits. Phleboliths are most commonly found in the pelvis region, and because women have more veins in that area they are at higher risk of developing this type of stone. In general, phleboliths are not clinically significant and do not cause symptoms, however there are cases in which a phlebolith is suspected to be causing an unrelated condition.
Pain in the abdomen, pelvis, hips or lower back is the most common patient complaint. The pain is usually related to a similar type of stone found within the urinary tract, which includes the kidneys, ureters, bladder and urethra. However the presence of one or more phleboliths in the absence of a ureteral stone (a kidney stone within the ureter) may cause this pain.
Patients with a phlebolith may develop thrombosis, which is the formation of a blood clot. Especially in cases in which the phlebolith is larger, the blood flow within the vein may be hindered, causing stasis (low blood flow), which can lead to the formation of a clot. Alternately, a phlebolith may be the symptom of thrombosis, as the stone may begin as a small clot that then becomes calcified.
The presence of a phlebolith may indicate a varicose condition in the pelvic veins, which means they are dilated or expanded. The dilation can occur due to the presence of a large amount of hormones such as estrogen, which is a vasodilator (able to dilate blood vessels). The presence of varicose veins can cause chronic pelvic pain.
A phlebolith in a vein near the kidney or bladder can cause symptoms similar to what a ureteral stone would cause, including the pain and discomfort. This makes identifying the exact location of the stone crucial so that a proper course of treatment can be administered.
Phleobliths are usually identified during an X-ray for an unrelated medical issue or to find a suspected ureteral stone. Since both types of stones appear as a small white spot on the X-ray it can be difficult to determine if it is in the vein or in the urinary tract. To determine the exact location, a doctor can perform an IVP (intravenous pylogram) test, in which a dye is injected into a vein and then X-rays are taken at timed intervals. The dye then moves through the urinary tract system, providing contrast so that the location of the stone can be determined.