Abstract
In our series of 30 operative cases of subcortical hemorrhages, 23 were considered spontaneous, since causes for the hemorrhages were not identified preoperatively. In 13 cases (56.5%) of these 23, small angiomatous malformations (SAM) were verified as sources of the bleeding. They were recognized as small hemorrhagic nodules or small vascular meshworks in the walls of the hematoma cavities. Histologically, 11 were arteriovenous malformations and 2 cavernous angiomas. From this result, we stress the significance of SAM as a cause of spontaneous hematoma and the importance of a meticulous search for and subsequent biopsy of a suspected lesion intraoperatively.
We analyzed these 13 cases with SAM, which included 8 males and 5 females ranging from 15 to 77 years of age; 4 were older than 60. Angiographically, no case showed any abnormal vascularity. In contrast with previous reports, most cases in our series showed rapidly progressive courses resulting in emergent operations. This seemed attributable to our criteria for operative investigation of spontaneous hematomas. It is suggested that SAM can be one of the important causes of severe intracerebral hemorrhages. On the other hand, in patients with hematomas who are treated nonoperatively, the presence of SAM can not be ruled out. When a follow-up CT scan suggests the presence of SAM and it is accessible, surgery should be considered.
