Cerebral perfusion analysis using computed tomography with contrast administration, including post-processing of parametric maps with determination of cerebral blood flow, cerebral blood volume, and mean transit time
CPT4 code
Name of the Procedure:
Cerebral Perfusion Analysis using Computed Tomography with Contrast Administration
Summary
This procedure involves using a special CT scan with injected contrast dye to measure blood flow, blood volume, and the time it takes for blood to travel through the brain. It helps doctors understand how well blood is reaching different parts of the brain.
Purpose
This procedure evaluates the brain's blood supply, helping to diagnose conditions like stroke, tumors, or other issues with blood flow in the brain. The goal is to identify abnormalities in cerebral perfusion and assist in planning appropriate treatment.
Indications
The procedure is typically recommended for patients:
- Experiencing symptoms such as sudden weakness, difficulty speaking, or vision problems that suggest a stroke.
- With known or suspected brain tumors.
- Suffering from other cerebrovascular diseases.
Patient criteria: Usually those with acute neurological deficits or suspicion of abnormal brain perfusion.
Preparation
- Patients may be asked to fast for a few hours before the procedure.
- Medications may need to be adjusted; consult with the healthcare provider.
- Pre-procedure assessments may include blood tests and a review of the patient’s medical history and allergies, especially to contrast media.
Procedure Description
- The patient lies on a CT scanner table.
- An intravenous (IV) line is placed for contrast dye administration.
- The CT scan is performed before and after the injection of the contrast dye.
- Post-processing software generates parametric maps showing cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT).
- No anesthesia is typically required.
Duration
The entire procedure usually takes about 30 to 60 minutes.
Setting
The procedure is conducted in a radiology department within a hospital or an outpatient imaging center.
Personnel
- Radiologist
- Radiologic technologist
- Possibly a nurse to assist with IV placement
Risks and Complications
- Allergic reactions to the contrast dye, which are usually mild but can be severe in rare cases.
- Kidney function impairment in patients with existing renal issues.
- Exposure to ionizing radiation, although kept within safe limits.
- Potential for contrast extravasation (leakage into surrounding tissue).
Benefits
- Accurate assessment of brain perfusion.
- Early detection of strokes or other cerebrovascular abnormalities.
- Helps in making informed decisions regarding treatment options.
Recovery
- Minimal recovery time; patients can typically resume normal activities shortly after.
- Patients are advised to drink plenty of fluids to help flush out the contrast dye.
- Follow-up evaluations or treatments may be planned based on the results.
Alternatives
- Magnetic Resonance Imaging (MRI) with perfusion techniques.
- Doppler ultrasound for certain vascular assessments.
- Each alternative has its own pros and cons, such as availability, cost, and specificity in imaging details.
Patient Experience
- Patients may feel a warm sensation when the contrast dye is injected.
- They need to stay still during the scan to ensure accurate images.
- Discomfort from lying still and the IV placement is usually minimal.
- Any discomfort is brief, and pain management is typically not necessary.