scout image
A preliminary radiographic image obtained before CT or MRI scanning to plan scan coverage and positioning.
Full Definition
A scout image, also called a scanogram or topogram, is a preliminary two-dimensional radiographic projection acquired before cross-sectional imaging to plan the examination. These images are obtained with minimal radiation dose and provide an overview of the patient's anatomy for positioning verification and scan range planning. In CT, scout images are typically acquired in anteroposterior and lateral projections, allowing technologists to prescribe precise scan coverage and avoid unnecessary radiation to areas outside the region of interest. Scout images also serve as reference tools for slice localization and can reveal obvious abnormalities that might affect scan protocols. In oncologic imaging, scout images help ensure complete coverage of target anatomy while minimizing radiation exposure to normal tissues.
Usage
Usage note: Different vendors may use different terminology (scout, scanogram, topogram).
In Context
- "Review the scout image to confirm proper patient positioning before initiating the helical scan." — CT acquisition protocol
- "The scout image shows the diaphragm position for accurate lung base coverage." — Chest CT planning