see also Putaminal hemorrhage.
Usually as a result of poorly controlled long standing hypertension.
It is probably not a factor in at least 35 % of basal ganglion hemorrhages.
The stigmata of chronic hypertensive encephalopathy are often present.
Most of the cases are spontaneous unilateral hemorrhage, and the volume of blood is usually < 30 cc 1).
Traumatic basal ganglia hematomas (TBGHs) are uncommon events in patients with closed head injuries.
Long standing poorly controlled hypertension leads to a variety of pathological changes in the vessels.
microaneurysms of perforating arteries (Microaneurysms of Charcot-Bouchard)
small (0.3-0.9 mm) diameter aneurysms that occur on small (0.1-0.3 mm) diameter arteries a distribution that matches incidence of hypertensive haemorrhages
found in hypertensive patients may thrombose, leak (see cerebral microhaemorrhages) or rupture
accelerated atherosclerosis: affects larger vessels
hyperplastic arteriosclerosis: seen in very elevated and protracted cases
Weakness may be the initial symptom with a basal ganglia hemorrhage
Typically a region of hyperdensity is demonstrated centred on the basal ganglia or thalamus. Not infrequently there may be an extension into the ventricles, with occasionally the parenchymal component being very small or inapparent.
The appearance of haemorrhage on MRI varies with time and to some degree the size of the haematoma (see ageing blood on MRI).