Cerebral AVM: Under diagnosed Reality and Rarity . Anatomical, Pathological, Clinical and Radiological Perspective .

Abstract

A simple headache can represent an ordinary cause or a severe life threatening cause. Many symptoms tend to undergo un noticed in life and even Great Physicians can miss potential dangerous and silent diseases or causes of such diseases. A Cerebral AVM may be described as a "ticking iological time bomb", carrying an accumulated risk of spontaneous haemorrhage of more than 2-3 % per year with a mortality of 6-10 % at the first hemorrhage and 13% at the second hemorrhage. AVM's can be located anywhere in the brain and can produce headaches, seizures, focal eurologic deficits, or intracranial hemorrhage. Intracranial hemorrhage from vascular malformations accounts for 1% of all strokes and 10% of all SAH's. The prevalence of AVM's among the general population is uncertain, but autopsy studies of unselected patients indicate that 4 to 5% harbor some
form of vascular malformation, of which only 10 to 15% produce symptoms. Familial cases of AVM's are rare, indicating that the problem reflects sporadic abnormalities in embryologic development. Cerebral AVMs may form during prenatal stages of a child’s development, either during
embryonic or fetal growth. AVMs are congenital lesions composed of a complex tangle of arteries and veins connected by one or more fistulae. The vascular conglomerate is called the nidus. The nidus has no capillary bed, and the feeding arteries drain directly to the draining  veins. The arteries have a deficient muscularis layer. The draining veins often are dilated owing to the high velocity of blood flow through the fistulae. Studies have found a certain number of cases form shortly after birth; however, the condition frequently presents in adults in their 20s or 30s.