[23] Surgical Experiences in South Africa.
[24] Edin. Med. Journ., 1909, p. 526.
[25] Johns Hopkins Hospital Bulletin, April, 1909.
CHAPTER V
INTRACRANIAL INJURIES: EXTRA- AND SUB-DURAL HÆMORRHAGES. INJURY TO THE BRAIN
HÆMORRHAGES
I. Extra-dural hæmorrhage.
Extra-dural hæmorrhage may be arterial or venous in origin. In the former case the blood is derived almost exclusively from the middle meningeal artery. When of venous origin the source is usually to be found in a laceration of one of the sinuses of the brain. When blood is poured out from a torn sinus it tends to occupy, and be widely diffused in, the subdural space. A venous extra-dural extravasation is relatively of infrequent occurrence, and the pressure exercised on the brain seldom suffices to permit of the development of local or general symptoms of cerebral compression. On these grounds extra-dural hæmorrhage may be regarded as almost necessarily of arterial origin, and as derived from a torn middle meningeal artery.