Cerebral Aneurysm

Introduction:

A consequence of cerebral aneurysm, aneurysmal subarachnoid hemorrhage (SAH) has devastating consequences. About 10% of individuals with aneurysmal SAH die before reaching medical attention, 25% die within 24 hours, and 40-49% die within 3 months. Mortality has been estimated to be as high as 65%, with most deaths occurring early in the clinical course.

Signs and Symptoms of Cerebral Aneurysm:

Symptoms associated with cerebral aneurysms and SAH are as follows:

• Headache
• Facial pain
• Alterations in consciousness
• Seizures
• Manifestations of meningeal irritation
• Autonomic disturbances
• Focal neurologic complaints
• Visual symptoms
• Respiratory dysfunction
• Cardiovascular instability
• Hormonal dysfunction
• Epistaxis

Lab studies used in the diagnosis and assessment of cerebral aneurysms include the following:

• Complete blood count (CBC) with platelets: Monitor for infection, evaluate anemia and identify bleeding risk
• Prothrombin time (PT)/activated partial thromboplastin time (aPTT): Identify a coagulopathy that increases bleeding risk
• Serum chemistries, including electrolytes and osmolarity: Obtain baseline studies to monitor hyponatremia, address arrhythmogenic abnormalities, assess blood glucose, and monitor hyperosmolar therapy for elevated intracranial pressure
• Liver function tests: Identify hepatic dysfunction that may complicate the clinical course
• Arterial blood gases: Assess blood oxygenation

Imaging studies used in the workup of cerebral aneurysms include the following:

• Computed tomography (CT) scanning: Aneurysmal SAH may be detected in 90-95% of cases
• Magnetic resonance imaging (MRI): Fluid-attenuated inversion recovery (FLAIR) sequences are very sensitive for SAH, although the comparison of CT scanning with MRI in the detection of SAH is controversial; dolichoectatic and giant aneurysms are identified readily with MRI
• Angiography: Conventional angiography is the definitive procedure for the detection and characterization of cerebral aneurysms
• Transcranial Doppler ultrasonography: This modality facilitates the diagnosis of vasospasm and serial monitoring of cerebral blood flow at the bedside
• Single-photon emission CT (SPECT) scanning, positron emission tomography (PET) scanning, xenon-CT (XeCT) scanning: With these techniques, cerebral blood flow studies may depict ischemia associated with vasospasm, although these modalities are not routinely employed
• Cervical spine imaging: Radiographic assessment of the cervical spine should be performed in all comatose patients with an unwitnessed loss of consciousness
• Echocardiography: Cardiac sources of embolism, including endocarditis and myxomas, may be visualized in cases of infectious or neoplastic aneurysms.
• A lumbar puncture may help establish the diagnosis of SAH in the absence of focal signs of mass effects. Aneurysmal SAH demonstrates hemorrhagic cerebrospinal fluid with a xanthochromic supernatant, although these findings may be absent within the first few hours following aneurysmal rupture.