Cerebral angiography is considered the gold standard for confirming the presence, size, and location of a cerebral aneurysm. It provides detailed visualization of cerebral blood vessels, enabling precise diagnosis and surgical planning.

Rationale for correct answer:
C. Cerebral angiography: This test offers the highest resolution imaging of intracranial vasculature, allowing clinicians to detect aneurysms with accuracy. It also helps evaluate the aneurysm’s shape and risk of rupture, making it essential for definitive diagnosis.

Rationale for incorrect answers:
A. Non-contrast CT scan: While useful for detecting subarachnoid hemorrhage from a ruptured aneurysm, it does not provide detailed vessel imaging to confirm or characterize the aneurysm itself.
B. Electroencephalogram (EEG): EEG measures electrical brain activity and is used for seizure evaluation, not aneurysm diagnosis.
D. Magnetic resonance imaging (MRI) without contrast: MRI can detect vascular abnormalities, but without contrast or specialized techniques like MRA, it is less definitive than angiography.

Take home points:

• Cerebral angiography remains the gold standard for aneurysm diagnosis.
• CT is valuable for detecting bleeding but not for detailed vascular assessment.
• Timely and accurate imaging is critical to prevent catastrophic rupture.

Before a cerebral angiogram, the nurse must ensure the patient is safe for contrast dye use, appropriately prepared with NPO status, and has a baseline vascular assessment. Obtaining a detailed history helps identify any conditions or medications that may affect the procedure or recovery. Sedatives are not always required and are administered only if prescribed.

Rationale for correct answers:
A. Assessing for any known allergies to iodine-based contrast dye: Essential to prevent allergic or anaphylactic reactions to the contrast used during angiography.
B. Ensuring the patient has been NPO for 6–8 hours: Reduces the risk of aspiration during the procedure, especially if sedation is required.
C. Checking and documenting peripheral pulses in the limb to be used: Provides a baseline for comparison after the procedure to detect vascular complications.
D. Obtaining a full medical history and current medication list: Critical for identifying bleeding risks (e.g., anticoagulants) and other potential contraindications.

Rationale for incorrect answer:
E. Administering a sedative to all patients to ensure they remain still: Sedation is not universally required; some patients undergo the procedure under local anesthesia with minimal or no sedation. Administration depends on the patient’s condition and provider’s order.

Take home points:

• Always assess for contrast dye allergy before angiographic procedures.
• NPO status helps prevent aspiration if sedation is used.
• Peripheral pulse checks are vital for detecting post-procedure vascular compromise.
• Sedation is individualized, not routine for every patient.

A non-contrast CT scan is the preferred initial imaging for head trauma because acute blood appears hyperdense and is easily identifiable without the obscuring effect of contrast. This allows for rapid detection of intracranial hemorrhage, which is critical in emergency management.

Rationale for correct answer:
A. Visualize blood more easily and quickly: Contrast dye can obscure fresh blood on imaging. A non-contrast CT is fast, widely available, and highly sensitive for detecting acute intracranial bleeding, making it the gold standard in acute head injury evaluation.

Rationale for incorrect answers:
B. Identify a brain tumor: While CT scans can sometimes detect tumors, MRI is generally preferred for tumor evaluation, and contrast is often used to enhance visualization of mass lesions.
C. Assess for vascular abnormalities: CT angiography or cerebral angiography is better for vascular assessment; a plain CT is not ideal for this purpose.
D. Minimize radiation exposure to the patient: The decision to use or avoid contrast is based on diagnostic needs, not radiation exposure; contrast does not affect the radiation dose.

Take home points:

• Non-contrast CT is the first-line imaging for acute head trauma to detect bleeding.
• Contrast is avoided initially because it can mask acute hemorrhage.
• MRI and contrast-enhanced CT are more useful for tumors and vascular lesions in non-emergent settings.

Post-cerebral angiogram care focuses on preventing bleeding at the puncture site, detecting neurological changes early, avoiding complications from contrast dye, and maintaining limb immobilization to promote hemostasis. Immediate ambulation is avoided to reduce the risk of bleeding.

Rationale for correct answers:
B. Checking the puncture site for bleeding or hematoma formation: This is critical to detect and manage hemorrhage early, which is a common complication due to the arterial puncture.
C. Assessing the patient's neurological status and level of consciousness: Neurological changes may indicate complications such as embolism or intracranial bleeding, requiring immediate intervention.
D. Keeping the patient's affected limb straight and immobilized for several hours: Immobilization reduces the risk of bleeding and allows the arterial puncture to heal properly.
E. Monitoring for signs of allergic reaction to the contrast dye: Allergic reactions can occur minutes to hours after exposure and may range from mild rash to severe anaphylaxis.

Rationale for incorrect answers:
A. Encouraging the patient to ambulate immediately to prevent clot formation: Early ambulation after an arterial procedure increases the risk of bleeding and hematoma formation; the patient should remain on bed rest with limb immobilization for several hours.

Take home points:

• Monitor puncture site closely for bleeding or hematoma after cerebral angiogram.
• Assess neurological status frequently to detect post-procedure complications early.
• Keep affected limb immobilized to prevent bleeding.
• Watch for delayed allergic reactions to contrast dye.

On a non-contrast CT scan, acute blood appears as a bright (hyperdense) area. This is a hallmark finding of a hemorrhagic stroke, which occurs when a blood vessel ruptures and bleeds into brain tissue. The high density is due to the clot’s protein content and the absence of dilution by cerebrospinal fluid.

Rationale for correct answer:
B. A hemorrhagic stroke: Acute intracranial bleeding appears bright on a non-contrast CT because the hemoglobin in clotted blood has high attenuation. This imaging helps differentiate hemorrhagic stroke from ischemic stroke, guiding immediate treatment decisions.

Rationale for incorrect answers:
A. An ischemic stroke: In the early stages, ischemic strokes may appear normal or show subtle hypodense changes on CT. They do not typically present as bright, hyperdense areas.
C. Multiple sclerosis: MS lesions are best detected with MRI and appear as hypodense or isodense areas on CT, not bright hyperdensities.
D. A brain abscess: Abscesses may appear as ring-enhancing lesions with contrast but are not hyperdense on non-contrast CT unless calcified or hemorrhagic.

Take home points:

• Acute blood is hyperdense on non-contrast CT and strongly suggests hemorrhage.
• CT scans are the preferred first-line imaging for suspected stroke to distinguish between hemorrhagic and ischemic types.
• Early identification of hemorrhagic stroke is essential because treatment differs drastically from ischemic stroke.