Interhemispheric subdural hematoma
Acute Interhemispheric Subdural Hematoma.
Chronic Interhemispheric Subdural Hematoma
Its natural history is still quite unknown in terms of potential origin and course.
They usually occur in patients with bleeding disorders and are associated with trauma in 83% of cases 2).
Other causes include history of birth trauma, forceps delivery, child abuse with shaking, hemodialysis, anticoagulation and aneurysmal bleeding 3).
Fruin et al. 4) suggested that an occipital blow in the sagittal plane lead to an interhemispheric ASDH because of the anatomic orientation of the veins in the interhemispheric fissure, which tend to course antero-medially from the cortex to the midline sinuses. Before the CT era, it was difficult to detect an interhemispheric ASDH. Though removal of the blood has proved to be an option in the management of these patients, there is danger due to the close proximity of the superior sagittal sinus and bridging veins. Some of these hematomas migrate superiorly (to a more favorable position) with time, as they liquefy. It is also conceivable that if a patient with an interhemispheric ASDH is relatively asymptomatic, initial conservative management might be followed by migration of the clot to a position over the convexity where removal is considerably less dangerous. Thus there is no consensus on the ideal management of these rare hematomas, conservative treatment may be followed in those who are neurologically stable or have concurrent risk factors, while surgical treatment should be reserved for those who have pronounced symptoms or neurological deficits 5).
The hyperdense hematoma can best be visualized on the coronal and sagittal views. This is in contrast with typical subdural hematomas, which can be best appreciated on the axial views. Thus, it is important to image all three main views of the brain looking out for interhemispheric hematoma 6).