A vertebral hemangioma is a vascular lesion within a vertebral body. Commonly, these are benign lesions that are found incidentally during radiology studies for other indications. Vertebral hemangiomas are a common etiology estimated to be found in 10-12% of humans at autopsy. They are benign in nature and frequentlyasymptomatic. Symptoms, if they do occur, are usually related to large hemangiomas, trauma, the hormonal and hemodynamic changes of pregnancy, or osseous expansion and extra-osseous extension into surround soft tissues or epidural region of the spinal canal.
Etiology and epidemiology
Vertebral hemangiomas are hamartomatous lesions, meaning that they arise from dysembryogenetic origin. They are made up of thin-walled vessels infiltrating the medullary cavity between bone trabeculae and are usually confined to the vertebral body. VHs are commonly seen incidentally while obtaining imaging for other indications. Only around 1% of hemangiomas become symptomatic. When symptomatic, they can cause pain and myelopathy by intra-spinal bleeding, bony expansion or extra-osseous extension into surround soft tissue or the posterior neural elements. Highly vascular hemangiomas can produce neurologic deficits without prominent evidence of spinal cord compression. The deficits in these cases are probably attributable to blood flow disturbances in the spinal cord.
Imaging characteristics
On computed tomography or radiograph, VHs can cause rarefaction with vertical striations or a coarse honeycomb appearance. A polka-dot appearance on CT scan represents a cross-section of reinforced trabeculae. Baudrez, Galant, and VandeBerg found that MRI appearance is dictated by histology of the tumor—Vascularity, interstitial edema, and interspersed fat. The presence of high or moderate signal intensity on both T1 and T2 images is related to the ration of fat to vessels and edema. For example, a VH with a high concentration of fat and a relatively low make-up of vessels and edema would show a high signal intensity on T1-weighted spin-echo images and intermediate signal intensity on T2-weighted fast spin echo images. Whereas a VH made-up of nearly equal portion of fat and vessels and edema would show intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images.
Symptomatic VHs have been treated with surgery, transarterial embolization, direct ethanol injection, radiotherapy, and vertebroplasty, each with varying degrees of success. Each of these methods can be indicated in specific clinical settings.
