Delayed Traumatic Intracerebral Hematoma: A Pathophysiological Classification and Literature Review.

Delayed traumatic intracerebral hematoma (DTICH) is a relatively common occurrence after a traumatic brain injury (TBI). Several case series have been performed to study DTICH, many of which offer different definitions of DTICH. Some definitions involve a delayed progression of an existing hemorrhage, and others involve a de novo intracerebral hematoma that was not evident on the initial trauma evaluation. We propose a classification system for DTICH that accounts for the subtleties in the clinical manifestation and pathophysiology of the different types of DTICH, with the ultimate goal of providing strategies to prevent and manage DTICH. Based on the senior author's clinical experience, we generated a classification system for DTICH, and each type of DTICH was illustrated with a case. We defined type 1A (case 1A), the classic presentation of DTICH as predominantly characterized in the literature, as an intracerebral hematoma unseen on initial computed tomography imaging that typically develops five days to one week following blunt or penetrating head trauma. We defined type 1B (case 1B) as a hematoma that forms after at least one week following trauma in areas of the brain initially hemorrhage-free. We defined type 2 (case 2) as a hematoma that develops rapidly following a surgical evacuation of a different hematoma. We defined type 3 (case 3) as a hematoma that develops after a traumatic head injury in areas of non-hemorrhagic contusion, usually frontal or temporal. A literature review was performed using select terms on PubMed to find articles related to DTICH, excluding articles describing DTICH from an underlying vascular injury. After performing the literature review and screening articles by title and/or abstract, a total of 79 articles were found to meet the inclusion and exclusion criteria. We recorded which type of DTICH from our classification system best correlated with the articles in our literature review. Taken together with results from the literature, the proposed classification system is based on the senior author's clinical experience. Overall, DTICH is a relatively common occurrence after head trauma, and our pathophysiologic classification has the potential to help outline future studies to recognize and prevent the development of DTICH.