In conjunction with directional terms, planes and sections are also used to describe locations within the body. Planes are a visual dissection of the body. An analogy of cutting a cake is useful. The cake can be cut in half vertically so there is a left and a right piece, but it can also be cut in half horizontally so that there is a top piece and a bottom piece. The place that is cut is called the plane, and the pieces on either side are the sections. These divisions can be applied to the human body as well. When an imaging scan is ordered for a patient, such as an X-ray, the scan will be done in the plane that allows the health care provider to best focus on the organ or region of interest.
The main planes are:
- Sagittal (lateral) plane: a vertical plane running from front to back that divides the body or any of its parts into right and left sections. The sagittal plane when cut at the midline divides the body into two equal halves, in which case it is called the median or midsagittal plane.
- Transverse (axial) plane: a horizontal plane that divides the body or any of its parts into upper and lower, or superior and inferior, sections. This plane is parallel to the ground.
- Coronal (frontal) plane: a vertical plane running from left to right; divides the body or any of its parts into anterior (front) and posterior (back) sections. When dividing the head using a coronal plane, one section would be the face, and the other one would be the back of the head.