Mid-Sagittal Plane

The mid sagittal plane is an imaginary line that halves the body into left and right parts. often known as the mid-line.

If the Image Receptor (IR) is parallel to the floor, as it would be if it was lying on the table or in a supine (horizontal) bucky

• When the MSP is parallel to the IR, the patient is lying on their side.
• When the MSP is perpendicular to the IR the patient is lying supine (lying on their back) or prone (lying on their front).

It follows the sagittal suture in the skull.