Aneurysm Essay
REVIEW OF LITERATURE Intracranial Aneurysm
The normal functioning of brain requires continuous supply of oxygen and othernutrients. Brain which consists of more than 86.1± 8.1 billion neurons have a highmetabolic rate compared to other cells found elsewhere in the body(Azevedoet al., 2009).The physiological demands for these cells are served by the densest vascularnetworks in the human body which receives 15% of cardiac output and 20% ofoxygen utilized by the body (Kumar et al., 2003). A compromised blood supply may¬¬¬cause permanent or transient damage to the neuron. The damage of neurons can bereversible or even irreversible which can lead to cell death if the blood supply is not completely restored(Purveset al., 2008). Intracranial Aneurysms …show more content…
(IA) are pathological dilations of blood vessels found in the brain caused by the weakening of vessel walls. Saccular Intracranial Aneurysm (SIA) is the most common type, which is also the most frequent cause of rupture (Frosenet al., 2011). A recent study by Lazzaroet al.,2010, showed that aneurysms associated with the Circle of Willis anomalies have an increased risk of rupture compared to those associated with a normal Circle of Willis. Physiological characterization of blood flow associated with Circle of Willis is done which may lead to hemodynamic changes with elevated flow rate, directly leading to formation of IAs and its rupture. IAs are classified both by size and shape.
Small aneurysms have a diameter of less than 15 mm. Larger aneurysms include thoseclassified as large (15 to 25 mm), giant (25 to 50 mm), and super-giant (over 50 mm)(Brismanet al., 2006). SIA, also known as ‘berry aneurysms’, appear as a round outpouching and are the most common form of cerebral aneurysm. Fusiform aneurysms represent a widening of a segment of an artery around the entire blood vessel, rather than just arising from a side of an artery's wall. They can rupture but the chance is quiet low. Micro- aneurysms typically occur in small blood vessels (less than 300micrometer in diameter), most often the lenticulostriate vessels of the basal ganglia, and are associated with chronic hypertension (Abbas et al., 2005).False aneurysms, also known as a pseudo aneurysm, is when there is a breach in the vessel wall such that blood leaks through the wall but seen in the adventitia or surrounding perivascular soft tissue. A direct communication of blood flow exists between the vessel lumen and the aneurysm lumen through the hole in the vessel wall. The risk ofrupture is higher than that of a true aneurysm of comparable size due to poor support of the aneurysm wall and thus false aneurysms generally require treatment (Pitton MB et
al.,2015)
The normal functioning of brain requires continuous supply of oxygen and othernutrients. Brain which consists of more than 86.1± 8.1 billion neurons have a highmetabolic rate compared to other cells found elsewhere in the body(Azevedoet al., 2009).The physiological demands for these cells are served by the densest vascularnetworks in the human body which receives 15% of cardiac output and 20% ofoxygen utilized by the body (Kumar et al., 2003). A compromised blood supply may¬¬¬cause permanent or transient damage to the neuron. The damage of neurons can bereversible or even irreversible which can lead to cell death if the blood supply is not completely restored(Purveset al., 2008). Intracranial Aneurysms …show more content…
(IA) are pathological dilations of blood vessels found in the brain caused by the weakening of vessel walls. Saccular Intracranial Aneurysm (SIA) is the most common type, which is also the most frequent cause of rupture (Frosenet al., 2011). A recent study by Lazzaroet al.,2010, showed that aneurysms associated with the Circle of Willis anomalies have an increased risk of rupture compared to those associated with a normal Circle of Willis. Physiological characterization of blood flow associated with Circle of Willis is done which may lead to hemodynamic changes with elevated flow rate, directly leading to formation of IAs and its rupture. IAs are classified both by size and shape.
Small aneurysms have a diameter of less than 15 mm. Larger aneurysms include thoseclassified as large (15 to 25 mm), giant (25 to 50 mm), and super-giant (over 50 mm)(Brismanet al., 2006). SIA, also known as ‘berry aneurysms’, appear as a round outpouching and are the most common form of cerebral aneurysm. Fusiform aneurysms represent a widening of a segment of an artery around the entire blood vessel, rather than just arising from a side of an artery's wall. They can rupture but the chance is quiet low. Micro- aneurysms typically occur in small blood vessels (less than 300micrometer in diameter), most often the lenticulostriate vessels of the basal ganglia, and are associated with chronic hypertension (Abbas et al., 2005).False aneurysms, also known as a pseudo aneurysm, is when there is a breach in the vessel wall such that blood leaks through the wall but seen in the adventitia or surrounding perivascular soft tissue. A direct communication of blood flow exists between the vessel lumen and the aneurysm lumen through the hole in the vessel wall. The risk ofrupture is higher than that of a true aneurysm of comparable size due to poor support of the aneurysm wall and thus false aneurysms generally require treatment (Pitton MB et
al.,2015)