A cerebral hemorrhage (or intracerebral hemorrhage, ICH), is a subtype of intracranial hemorrhage that occurs within the brain tissue itself. Intracerebral hemorrhage can be caused by brain trauma, or it can occur spontaneously in hemorrhagic stroke. Non-traumatic intracerebral hemorrhage is a spontaneous bleeding into the brain tissue.<1>
A cerebral hemorrhage is an intra-axial hemorrhage; that is, it occurs within the brain tissue rather than outside of it. The other category of intracranial hemorrhage is extra-axial hemorrhage, such as epidural, subdural, and subarachnoid hematomas, which all occur within the skull but outside of the brain tissue. There are two main kinds of intra-axial hemorrhages: intraparenchymal hemorrhage and intraventricular hemorrhages. As with other types of hemorrhages within the skull, intraparenchymal bleeds are a serious medical emergency because they can increase intracranial pressure. The mortality rate for intraparenchymal bleeds is over 40%.[2]
Patients with intraparenchymal bleeds have symptoms that correspond to the functions controlled by the area of the brain that is damaged by the bleed.[9] Other symptoms include those that indicate a rise in intracranial pressure due to a large mass putting pressure on the brain.[9] Intracerebral hemorrhages are often misdiagnosed as Subarachnoid hemorrhages due to the similarity in symptoms and signs.
Intraparenchymal hemorrhage can be recognized on CT scans because blood appears brighter than other tissue and is separated from the inner table of the skull by brain tissue. The tissue surrounding a bleed is often less dense than the rest of the brain due to edema, and therefore shows up lighter on the CT scan.
Treatment
Treatment depends substantially of the type of ICH. Rapid CT scan and other diagnostic measures are used to determine proper treatment, which may include both medication and surgery.
The risk of death from an intraparenchymal bleed in traumatic brain injury is especially high when the injury occurs in the brain stem.[2] Intraparenchymal bleeds within the medulla oblongata are almost always fatal, because they cause damage to cranial nerve X, the vagus nerve, which plays an important role in blood circulation and breathing.[5] This kind of hemorrhage can also occur in the cortex or subcortical areas, usually in the frontal or temporal lobes when due to head injury, and sometimes in the cerebellum.[5][13]
For spontaneous ICH seen on CT scan, the death rate (mortality) is 34–50% by 30 days after the insult.[1]
^ Shepherd S. 2004. "Head Trauma." Emedicine.com. Retrieved on June 19, 2007.
^Major Risk Factors for Intracerebral Hemorrhage in the Young Are Modifiable Edward Feldmann, MD; Joseph P. Broderick, MD; Walter N. Kernan, MD; Catherine M. Viscoli, PhD; Lawrence M. Brass, MD; Thomas Brott, MD; Lewis B. Morgenstern, MD; Janet Lee Wilterdink, MD Ralph I. Horwitz, MD. Published in Stroke. 2005;36:1881.
^ Graham DI and Gennareli TA. Chapter 5, "Pathology of Brain Damage After Head Injury" Cooper P and Golfinos G. 2000. Head Injury, 4th Ed. Morgan Hill, New York.