Hemodynamics and cerebrovascular disease

A hemorrhagic stroke develops when a cerebral blood vessel ruptures, allowing blood to escape into the surrounding brain tissue, as in intracerebral hemorrhage (ICH), or into the subarachnoid space, as in subarachnoid hemorrhage (SAH). Because the skull is a rigid compartment, the sudden presence of extravascular blood rapidly increases intracranial pressure and compresses adjacent neural structures, leading to immediate tissue injury and impaired cerebral perfusion.Mass Effect and Primary...

A hemorrhagic stroke is an acute neurological event that occurs when a weakened cerebral blood vessel ruptures, allowing blood to accumulate within or around the brain. The sudden release of blood forms a focal hematoma that increases intracranial pressure, displaces neural tissue, and can obstruct cerebrospinal fluid pathways. These effects may be compounded by intraventricular extension of the hemorrhage, cerebral edema, or compression of adjacent structures, all of which contribute to...

Vasogenic edema is a major form of cerebral edema characterized by abnormal accumulation of fluid in the brain’s extracellular space due to disruption of the blood–brain barrier (BBB). The BBB is a specialized structure composed of endothelial cells connected by tight junctions, supported by astrocytic endfeet and a basement membrane. Under normal conditions, it tightly regulates the movement of ions, proteins, and solutes between the bloodstream and brain parenchyma. When this barrier loses...

Cerebral edema is a pathological increase in brain water content that disrupts intracranial pressure regulation and impairs neurological function. Because the cranial vault is rigid, even modest increases in tissue volume can compromise cerebral perfusion, distort neural structures, and initiate secondary injury. Cerebral edema develops through four principal mechanisms: vasogenic, cytotoxic, interstitial, and ionic.Vasogenic EdemaVasogenic edema arises from disruption of the blood–brain...

Disorders affecting blood volume, vascular tone, or vascular function can disrupt vascular homeostasis, including conditions like hypertension, hemorrhage, and shock.
Blood Pressure: Hypertension and Hypotension
Normal blood pressure is 120/80 mm Hg. Elevated blood pressure is 120-129/under 80 mm Hg. Hypertension, warranting treatment at 130/80 mm Hg, is often asymptomatic and can lead to severe cardiovascular events, aneurysms, peripheral arterial disease, chronic renal disease, or cardiac...

The human body's intricate network of arteries ensures that every organ system receives the necessary oxygen and nutrients for optimal function. The arterial network in the head and neck region is particularly complex, providing vital blood flow to the brain, eyes, and other critical structures. Prominent arteries in this region include the internal carotid arteries and the vertebral arteries.
The internal carotid arteries supply blood to the anterior portion of the cerebrum. They enter the...