Bellingham Technical College Biology 130 Sectional Anatomy Week 3: The Brain Instructor: Ken Wilkerson E-mail: firstname.lastname@example.org
Labeling Exercises• Use your pgdn key to scroll through the following scans and try to name the labeled anatomy before revealing the answers.
A Clivus B Medulla Oblongata C 4th Ventricle D CerebellumMRI WO Contrast T2 Weight
A Middle Cerebral Artery B Posterior Cerebra Artery C Mid-Brain D Vermis of CerebellumMRI WO Contrast T2 Weight
A Ant. Horn of lateral ventricle B Head of caudate nucleus C Thalamus D Post. Horn of lateral VentricleCT Brain WO contrast
A. Carotid Artery B. Jugular Vein C. Vertebral ArteriesCTA Brain
A. Anterior Cerebral Artery B. Middle Cerebral Artery C. Post. Cerebral ArteryCTA Brain Maximum Intensity Projection
Intracranial Hemorrhage• As an imaging technologist in advanced imaging modalities, it is important to understand the differences, and recognize the physical appearance of different classifications of intracranial hemorrhage.• The following slides will help you recognize and identify different types of intracranial hemorrhage.
Types of Intracranial HemorrhageIntra-axial Extra-axial• intraparenchymal • Epidural – Bleeding within the brain – Bleeding that occurs between the dura and cranial bone. tissue. • Subdural• Intraventricular – Subdural hematoma occurs when – Bleeding into the ventricles there is tearing of the bridging vein between the cerebral cortex and a draining venous sinus. At times they may be caused by arterial lacerations on the brain surface. • Subarachnoid – meningeal layers.occuring between the arachnoid and pia
Intra-axial• intraparenchymal • Intraventricular – Intraventricular hemorrhage has – Nontraumatic intraparenchymal hemorrhage been found to occur in 35% of most commonly results from hypertensive moderate to severe traumatic brain damage to blood vessel walls e.g.: - injuries. The injury requires a hypertension -eclampsia - drug abuse, but it also may be due great deal of force to cause. Thus the to autoregulatory dysfunction with excessive hemorrhage usually does not occur cerebral blood flow e.g.: - reperfusion injury - without extensive associated hemorrhagic transformation - cold exposure - damage, and so the outcome is rarely rupture of an aneurysm or arteriovenous malformation (AVM) - arteriopathy good. (e.g. cerebral amyloid angiopathy, moyamoya) – Prognosis is also dismal when IVH - results from intracerebral altered hemostasis (e.g. thrombolysis, anticoa gulation, bleeding diathesis) - hemorrhagic hemorrhage related to high blood necrosis (e.g.tumor, infection) - venous pressure and is even worse outflow obstruction (e.g. cerebral venous when hydrocephalus follows. It sinus thrombosis). Nonpenetrating and can result in dangerous increases penetrating cranial trauma can be also common causes of intracerebral hemorrhage. in intracranial pressure and can cause potentially fatal brain herniation.
Extra-Axial• Epidural Hematoma – Bleeding between the dura of the brain and the inner surface of the cranium. • This is a traumatic injury caused by a sharp blow to the head. Often this type of hemorrhage will be associated with an underlying cranial fracture.
Extra-Axial• Subdural Hematoma• Subdural hematomas are usually the result of a serious head injury. When one occurs in this way, it is called an "acute" subdural hematoma. Acute subdural hematomas are among the deadliest of all head injuries. The bleeding fills the brain area very rapidly, compressing brain tissue. This often results in brain injury and may lead to death.• Subdural hematomas can also occur after a very minor head injury, especially in the elderly. These may go unnoticed for many days to weeks, and are called "chronic" subdural hematomas. With any subdural hematoma, tiny veins between the surface of the brain and its outer covering (the dura) stretch and tear, allowing blood to collect. In the elderly, the veins are often already stretched because of brain atrophy (shrinkage) and are more easily injured.