Impaired Cerebral Blood Flow Disorders

Impaired Cerebral Blood Flow Disorders

CEREBRAL BLOOD FLOW

Impaired cerebral blood flow disorders are extremely common and factors such as the lesion site, existing collateral’s, and the amount of tissue affected determines the actual neurological deficit that results. The impaired blood flow may have a number of causes. Things such as alterations in blood pressure, changes in the arterial walls, and occlusions of the arterial lumen are some of the more important causes.

The brain is supplied with blood by two internal carotid arteries and two vertebral arteries. These arteries form the anastomosis known as the Circle of Willis. In 1951, two researchers, McDonald and Potter demonstrated that, "the blood supply to half of the brain is provided by the internal carotid and vertebral artery of that side, and that their respective streams come together in the posterior communicating artery at a point where the pressure of the two is equal and they do not mix." (Snell, p514). This is important to keep in mind when considering just how significant the collateral circulation truly is. "If, however, the internal carotid or vertebral artery is occluded, the blood passes forward or backward across that point to compensate for the reduction in blood flow. The circulus arteriosus also permits the blood to flow across the midline, as shown when the internal carotid or vertebral artery on one side is occluded." This provides some relief for occlusions in the major vascular supply. Another important finding, was that the blood that flows from the two vertebral arteries remain on the same side of the lumen and does not mix while passing through the basilar artery. These are important items for the major vascular supply, however, once...

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...ain focus of the physician in treating a stroke patient must be the individual patient and his/her underlying lesion. Cerebral blood flow deficiency is not limited in its scope of patients it can afflict. The care of stroke patients is changing and the optimal management of the patient’s condition demands the careful consultation of a well-informed team of physicians.

Works Cited:

Auer, L. M. & Ladurner, G. "Alterations of the Cerebral Blood Volume," p.p. 233-38.

Snell, R. S. "The Blood Supply of the Brain," Clinical Neuroanatomv for Medical Students. Little, Brown and Co., Boston/Toronto, p.p. 507-24.

Stern, B. J. "Cerebrovascular Disease and Pregnancy’ Neurological Disorders of Pregnancy". p.p. 32-34.

Walton, John. "Disorders of the cerebral circulation," Brains Diseases of the Central Nervous System. Oxford Univ. Press, New York; p.p. 219.