Question

A retrospective reconstruction, in which the reconstruction field-of-view is varied, uses:

1) reconstructed image in the sagittal plane
2) CT raw data
3) more photons
4) CT image data

Answer 1

A retrospective reconstruction in CT varies the field-of-view and relies on CT raw data to create detailed three-dimensional images.

Step-by-step explanation:

A retrospective reconstruction, which is a technique used in computed tomography (CT), varies the reconstruction field-of-view and is primarily based on CT raw data. This process utilizes complex computer image processing to analyze the relative absorption of X-rays taken from multiple directions around the patient. As the patient is moved through the scanner, various slices are captured, which can be further analyzed to render three-dimensional images. Unlike additional photons to enhance image quality, this reconstruction technique manipulates the already captured raw data to adjust the field-of-view and improve details in the resultant images. A reconstructed image in the sagittal plane or any other specific plane, is a product derived from the CT raw data, not a direct requirement of the process itself.