Specific Imaging Findings

The characteristic MR imaging appearance of capillary telangiectasia is a small area with ill-defined margins of faint “brush-like”, stippled, or “lacy” contrast enhancement, and without any mass effect, perifocal edema, or gliosis. In over half of the cases it is invisible on T2WI and FLAIR images, and in the remaining cases it shows mild T2 hyperintensity. The typical additional diagnostic clue, which is not always present, is a mild hypointensity on T2*-weighted images (GRE, SWI, EPI, PWI, BOLD), without clear “blooming” artifact. CT is almost always negative, while in rare cases it shows small calcifications. Angiography usually fails to reveal any abnormality. The most common location is in the pons, but it can be found anywhere in the brain and more rarely in the spinal cord. Capillary telangiectasia varies in size between a few millimeters and 2 cm; it may be associated with an adjacent developmental venous anomaly (DVA) and/or cavernoma (cavernous malformation).

Pertinent Clinical Information

Capillary telangiectasia is almost invariably an incidental, asymptomatic finding with very slow or absent growth. There are rare reports of symptomatic telangiectasias, which are usually larger than 1 cm in size. Clinical response and relapse on steroid treatment have been described. Hemorrhage is exceptional, and is thought to arise from commonly associated cavernous malformations. Capillary telangiectasia may also possibly be a radiation-induced vascular malformation. Due to its benign course, treatment and follow-up are not warranted. Misdiagnosis with metastatic neoplasms is common and should be avoided.