Resolving intracerebral hematoma: alteration of the "ring sign" with steroids.

A ring of contrast enhancement is seen on CT scans of resolving intracerebral hematomas. This ring can be modified with steroid administration in the early stages; however, enhancement seen in the later stages is not affected. Evidence suggests that the early ring is due to blood-brain barrier breakdown, and the later enhancement is due to vascular granulation tissue. The following six stages of hematoma resorption were identified depending on the hematoma density, the presence or absence of a ring of enhancement, and the response of the ring to steroid administration: I = dense hematoma without enhancement; II = decreasing density, enhancement, modification of enhancement with steroid; III = isodense hematoma, enhancement, modification with steroid; IV = lucent hematoma, enhancement, modification with steroid; V = lucent hematoma, enhancement, no modification with steroid; and VI = healed, no enhancement.