Multidetector computed tomography pulmonary angiography: does arm position affect pulmonary artery enhancement?

Area of Science:

• Radiology
• Medical Imaging
• Cardiovascular Imaging

Background:

• Computed tomographic pulmonary angiography (CTPA) is crucial for diagnosing pulmonary embolism.
• Optimal contrast enhancement in the pulmonary arteries is vital for accurate CTPA interpretation.
• Patient positioning, including arm placement, may influence image quality and diagnostic yield.

Purpose of the Study:

• To determine if patient arm position affects pulmonary artery contrast enhancement during CTPA.
• To assess the impact of arm position on image artifacts and central venous compression.

Main Methods:

• A comparative study involving 180 patients undergoing CTPA for suspected pulmonary embolism.
• Patients were divided into two groups: one with arms at their side and another with arms overhead.
• Pulmonary artery enhancement, beam-hardening artifact, and central venous compression were quantitatively assessed.

Main Results:

• No significant difference in pulmonary artery enhancement was observed between the arm-down and arm-up positions (P = 0.65).
• Greater central venous compression (P < 0.05) and increased beam-hardening artifact from the superior vena cava (SVC) (P < 0.0001) were noted with the arms positioned overhead.
• These findings suggest potential for reduced image quality with the arm-up position.

Conclusions:

• Patient arm position does not influence pulmonary artery enhancement in CTPA.
• The arm-up position is associated with increased central venous compression and SVC beam-hardening artifact.
• Standardizing arm position may be necessary to optimize CTPA image quality and reduce artifact.