What cassette size is required for a Lateral Thoracic X-ray?

The correct choice for the cassette size required for a lateral thoracic X-ray is 14"x17". This size is optimal as it allows for adequate coverage of the thoracic cavity, providing a clear and complete image of the chest structures. The lateral view specifically requires a larger field to encompass the entire thoracic region from the apex of the lungs to the diaphragm, ensuring that critical anatomical details are captured without clipping any portions of the anatomy.

Using a 14"x17" cassette facilitates proper positioning and ensures the alignment of the X-ray beam, which is crucial for accurate diagnostics. The larger size can accommodate the commonly varying widths of patients’ thoraxes, making it a versatile choice in clinical settings. In contrast, smaller cassette sizes may not be suitable as they might restrict the captured area, leading to incomplete diagnostic information.