Which important factor should be considered when acquiring CT images for treatment planning?

When acquiring CT images for treatment planning, ensuring that the CT table is flat is crucial for several reasons. A flat table provides a consistent and stable surface for patient positioning, which is essential for accurate imaging and treatment delivery. This helps to minimize variations that can arise from table curvature or tilting, which can lead to inconsistencies in the images obtained. Accurate representation of the patient's anatomy is vital for precise targeting of radiation therapy, ensuring that the treatment is delivered effectively and safely.

The use of immobilization devices is often necessary to ensure that patients remain in the same position throughout the imaging and treatment processes. Therefore, not utilizing them contradicts standard practices aimed at enhancing accuracy. Additionally, while contrast media can sometimes be utilized to improve diagnostic quality for certain conditions, it might not always be appropriate for treatment planning scenarios based on specific protocols and the region being treated. Finally, the portability of the CT scanner may be beneficial in certain situations, but the primary focus for treatment planning is the stabilization and accuracy afforded by a flat table.