Spinal intradural extramedullary capillary hemangioma: MR imaging findings

Abstract

Spinal intradural extramedullary capillary hemangiomas are extremely rare. We present the MR imaging and histologic findings in three patients with this abnormality. The three patients were men who had symptoms of either myelopathy (n = 2) or radiculopathy (n = 1). The tumors were well demarcated, 1.5-2.0 cm in diameter, and were located at the posterior or posterolateral portion of the thecal sac (one at the L1 level and the other two at the midthoracic level). On MR images, the tumor showed isointensity relative to the spinal cord on T1-weighted images, hyperintensity on T2-weighted images, and strong homogeneous enhancement on contrast-enhanced T1-weighted images in all three patients. In two patients, the dural tail sign was observed. Capillary hemangioma should be included in the differential diagnosis of a spinal intradural extramedullary tumor.

fig 1.

Case 1. Sagittal T1-weighted (A), T2-weighted (B), and contrast-enhanced T1-weighted (C) MR images show a well-defined solid enhancing mass within the thecal sac at the L1 level. A vertical linear enhancing structure within the thecal sac, as seen on C, is presumably due to a radiculomedullary vein rather than a compressed root with breakdown of nerve-blood barrier. On a photomicrograph of capillary hemangioma (D), the excised tumor consists of lobules of small capillary-sized vessels (C) separated by fibrous septa (S). Note a feeding vessel (F) with larger caliber size and medium-sized branching vessels (B) (H&E, ×40).

fig 2.

Case 2. Sagittal T1-weighted (A), T2-weighted (B), and contrast-enhanced sagittal (C) and axial (D) T1-weighted MR images demonstrate a densely enhancing extramedullary solid tumor on the right side of the thecal sac at the T5–T6 level, causing compressive myelopathy.

fig 3.

Case 3. Unenhanced sagittal (A) and contrast-enhanced sagittal (B) and axial (C) T1-weighted MR images show a markedly enhancing intradural extramedullary mass displacing the spinal cord anteriorly at the T4–T5 level.