dam- age to the nucleus and spinal tract of the trigeminal nerve; ( 3 ) contralateral loss of pain and temperature (of the body) due to damage to the spinothalamic tract; ( 4 ) vertigo, nausea, vomiting, and nystagmus due to damage to portions of the vestibular nuclei; ( 5 ) ipsilateral Horner’s syndrome due to damage to hypothalamospinal fibers descending through the lateral medulla; and (6 ) ipsilateral gait and limb ataxia due to damage to the cerebellum is characterized by the following symptoms: LATERAL MEDULLARY SYNDROME
Epidural Hematoma Head injury may result in loosening of the periosteal dura from the cranium, and an artery (e.g., middle meningeal artery) may be damaged leading to extravasation of blood to form an epidural hematoma. The patient usually expe- riences headache, disorientation, and lethargy. Subdural Hematoma Normally, there is no space at the junction of dura and sub- arachnoid mater; branches of veins pass through the sub- arachnoid space to enter the dural sinuses. Head injury may damage these veins, causing extravasation of blood, which creates a space between the dura and subarachnoid to form a subdural hematoma. HEMATOMAS
Head trauma may cause rupture of an intracranial aneurysm (local dilatation of an artery or vein resulting in a bulge and weakening of the vessel wall) resulting in extravasation of blood into the subarachnoid space. The aneurysms may be congenital or caused by pathological processes. The extravasated blood may be sequestered in the subarachnoid space, or it may collect in cisterns. Subarachnoid hemorrhage is associated with intense headache, nausea and vomiting, and, finally, unconsciousness. SUBARACHNOID HEMORRHAGE
ses involving the blood vessels that supply the brain can cause stroke, which is characterized by an acute onset of neurologic deficit lasting for at least 24 hours. A stroke can be caused by blockage of blood vessels (occlusive stroke) or by bleeding from vessels (hemorrhagic stroke). Occlu- sive strokes are generally caused by atherosclerotic lesions or thrombosis in blood vessels supplying the brain. Hemorrhagic strokes are generally caused by long-standing high blood pressure or aneurysms in the vessels supplying the brain. When bleeding occurs at the surface of the brain, it is called an extraparenchymal hemorrhage. STROKE
Insufficient blood flow to the brain is called brain ischemia; during brain ischemia, oxygen and glucose delivery to the brain tissue is reduced. In addition, toxic metabolites, such as lactic acid, cannot be removed efficiently due to reduced blood flow. Brief loss of consciousness caused by general- ized cerebral ischemia due to insufficient flow of oxygenated blood to the brain is called syncope.
- Fall '19
- Anterior cerebral artery, Middle cerebral artery, posterior cerebral artery