Cerebral Aneurysm
A cerebral aneurysm (also known as an intracranial or intracerebral aneurysm) is a weak spot on a blood vessel in the brain that bulges out and fills with blood that can put pressure on a nerve or the surrounding brain tissue. It may also leak or rupture, spilling blood into the nearby tissue (called a hemorrhage). Some cerebral aneurysms, mostly those that are very small, do not bleed or cause other problems. Cerebral aneurysms can occur anywhere in the brain, but most are located along a loop of arteries that run between the base of the brain and the base of the skull.
Diagnosis
Diagnosis of Ruptured Cerebral Aneurysm
A ruptured cerebral aneurysm leads to bleeding within the brain, causing sudden onset of very severe headaches, loss of consciousness, stiff neck or seizures, serious complications and death. These tests are the main tools used to diagnose a ruptured cerebral aneurysm:
Computed tomography (CT) An X-ray procedure that produces detailed images of the brain in cross-sectional slices. CT scans are very sensitive in detecting blood in the subarachnoid space from a ruptured aneurysm. The scan shows the distribution of blood in the brain, providing significant evidence regarding the aneurysm's location.
Magnetic resonance imaging (MRI) uses computer-generated radio waves and a powerful magnetic field to create detailed images of the brain and other body structures. Magnetic resonance angiography (MRA) produces more detailed images of blood vessels. These painless, noninvasive procedures can demonstrate the size and shape of an unruptured aneurysm and can identify bleeding in the brain.
A cerebrospinal fluid examination (CSF) In some cases, the physician may consider a subarachnoid hemorrhage, but the hemorrhage is not discovered on a CT scan. The CSF can help verify a ruptured aneurysm by identifying blood in the cerebrospinal fluid. A needle is introduced into the lower back to remove a small amount of spinal fluid.
Diagnosis of Unruptured Aneurysm
Unruptured aneurysm patients experience headaches or localized abnormalities in brain function. Physicians use magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and computed tomography angiography (CTA) to diagnosis this condition.
If an aneurysm or subarachnoid hemorrhage is found, the physician may perform a diagnostic test known as a cerebral angiogram to localize the aneurysm. A catheter (thin tube) is placed into an artery in the leg and guided through the bloodstream to the arteries in the neck that lead to the brain. Dye is injected into the arteries as X-rays are taken. These images provide a map of the arteries. MRI, MRA, and CTA scanning also can be used to find an aneurysm, but a cerebral angiogram usually provides more definitive information.
Screening for cerebral aneurysms using MRI, MRA or CTA is recommended for people at high risk, including those with a considerable family history of cerebral aneurysms and those with a disease called autosomal dominant polycystic kidney disease.
Causes
Usually, no definite cause of the aneurysm is established. Though, factors that increase the risk of cerebral saccular aneurysms include:
Genetics or an inherited condition
High blood pressure or hardening of the arteries in the brain
Cigarette smoking
A blood clot that goes to the brain
Some types of infection
Injury or trauma to the head
Habitual cocaine use
Treatment
The goal of treatment is to prevent future hemorrhage. There are two major ways this can be accomplished.
Surgery
The most common treatment for cerebral aneurysms is open surgery under general anesthesia. The neurosurgeon makes an incision in the scalp, makes a window in the skull, locates the aneurysm, and places a metal clip across the neck of the aneurysm to inhibit rupture. Advanced microsurgical techniques have significantly reduced the risks of surgery; yet, the outcome is related with the aneurysm's size, location, and shape.
Endovascular Therapy
In endovascular therapy, a neuroradiologist passes a catheter through an artery and places detachable platinum coils in the aneurysm. These devices prevent bleeding and protect against subarachnoid hemorrhage. Gaining recognition in the treatment of both ruptured and unruptured aneurysms, endovascular therapy offers a less invasive option to surgery for some patients with difficult-to-reach aneurysms.
The procedure is typically done under general anesthesia to keep the head still during placement of the coils.
Monitoring
Some aneurysms have such a low risk of rupture that periodic monitoring offers a preferable method to treatment.
According to a recent study at Mayo Clinic, patients with rather small aneurysms — under ¼ inch in diameter — located in the front portion of the brain had the lowest risk of subarachnoid hemorrhage. Patients with aneurysms ½ inch or more in diameter in the back part of the brain had the highest risk. Patients with a history of subarachnoid hemorrhage from a previous aneurysm also had a higher risk of subarachnoid hemorrhage. Rupture risk also increased significantly in patient’s age 50 and older, with the highest risk in patients age 60 and above. A history of rupture due to another aneurysm increased the risk of rupture as well.
As a result of this study, many neurologists and neurosurgeons now recommend a more conservative method instead of surgery for patients without a history of subarachnoid hemorrhage who have small aneurysms located in the front portion of the brain.
A cerebral aneurysm (also known as an intracranial or intracerebral aneurysm) is a weak spot on a blood vessel in the brain that bulges out and fills with blood that can put pressure on a nerve or the surrounding brain tissue. It may also leak or rupture, spilling blood into the nearby tissue (called a hemorrhage). Some cerebral aneurysms, mostly those that are very small, do not bleed or cause other problems. Cerebral aneurysms can occur anywhere in the brain, but most are located along a loop of arteries that run between the base of the brain and the base of the skull.
Diagnosis
Diagnosis of Ruptured Cerebral Aneurysm
A ruptured cerebral aneurysm leads to bleeding within the brain, causing sudden onset of very severe headaches, loss of consciousness, stiff neck or seizures, serious complications and death. These tests are the main tools used to diagnose a ruptured cerebral aneurysm:
Computed tomography (CT) An X-ray procedure that produces detailed images of the brain in cross-sectional slices. CT scans are very sensitive in detecting blood in the subarachnoid space from a ruptured aneurysm. The scan shows the distribution of blood in the brain, providing significant evidence regarding the aneurysm's location.
Magnetic resonance imaging (MRI) uses computer-generated radio waves and a powerful magnetic field to create detailed images of the brain and other body structures. Magnetic resonance angiography (MRA) produces more detailed images of blood vessels. These painless, noninvasive procedures can demonstrate the size and shape of an unruptured aneurysm and can identify bleeding in the brain.
A cerebrospinal fluid examination (CSF) In some cases, the physician may consider a subarachnoid hemorrhage, but the hemorrhage is not discovered on a CT scan. The CSF can help verify a ruptured aneurysm by identifying blood in the cerebrospinal fluid. A needle is introduced into the lower back to remove a small amount of spinal fluid.
Diagnosis of Unruptured Aneurysm
Unruptured aneurysm patients experience headaches or localized abnormalities in brain function. Physicians use magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and computed tomography angiography (CTA) to diagnosis this condition.
If an aneurysm or subarachnoid hemorrhage is found, the physician may perform a diagnostic test known as a cerebral angiogram to localize the aneurysm. A catheter (thin tube) is placed into an artery in the leg and guided through the bloodstream to the arteries in the neck that lead to the brain. Dye is injected into the arteries as X-rays are taken. These images provide a map of the arteries. MRI, MRA, and CTA scanning also can be used to find an aneurysm, but a cerebral angiogram usually provides more definitive information.
Screening for cerebral aneurysms using MRI, MRA or CTA is recommended for people at high risk, including those with a considerable family history of cerebral aneurysms and those with a disease called autosomal dominant polycystic kidney disease.
Causes
Usually, no definite cause of the aneurysm is established. Though, factors that increase the risk of cerebral saccular aneurysms include:
Genetics or an inherited condition
High blood pressure or hardening of the arteries in the brain
Cigarette smoking
A blood clot that goes to the brain
Some types of infection
Injury or trauma to the head
Habitual cocaine use
Treatment
The goal of treatment is to prevent future hemorrhage. There are two major ways this can be accomplished.
Surgery
The most common treatment for cerebral aneurysms is open surgery under general anesthesia. The neurosurgeon makes an incision in the scalp, makes a window in the skull, locates the aneurysm, and places a metal clip across the neck of the aneurysm to inhibit rupture. Advanced microsurgical techniques have significantly reduced the risks of surgery; yet, the outcome is related with the aneurysm's size, location, and shape.
Endovascular Therapy
In endovascular therapy, a neuroradiologist passes a catheter through an artery and places detachable platinum coils in the aneurysm. These devices prevent bleeding and protect against subarachnoid hemorrhage. Gaining recognition in the treatment of both ruptured and unruptured aneurysms, endovascular therapy offers a less invasive option to surgery for some patients with difficult-to-reach aneurysms.
The procedure is typically done under general anesthesia to keep the head still during placement of the coils.
Monitoring
Some aneurysms have such a low risk of rupture that periodic monitoring offers a preferable method to treatment.
According to a recent study at Mayo Clinic, patients with rather small aneurysms — under ¼ inch in diameter — located in the front portion of the brain had the lowest risk of subarachnoid hemorrhage. Patients with aneurysms ½ inch or more in diameter in the back part of the brain had the highest risk. Patients with a history of subarachnoid hemorrhage from a previous aneurysm also had a higher risk of subarachnoid hemorrhage. Rupture risk also increased significantly in patient’s age 50 and older, with the highest risk in patients age 60 and above. A history of rupture due to another aneurysm increased the risk of rupture as well.
As a result of this study, many neurologists and neurosurgeons now recommend a more conservative method instead of surgery for patients without a history of subarachnoid hemorrhage who have small aneurysms located in the front portion of the brain.
Information from: mayoclinic.org & HealthLink.com
