All references and terminology refer to the patient in an upright, standing position with feet and palms facing forward and both thumbs pointed out 90° to the side; this position is universally known as the Standard Anatomical Position. Standardization allows for all landmarks on a patient to be identified and agreed upon with precision by everyone in the operating room. During a surgery, the patient is normally positioned supine or prone with arms tucked along side for both positions or alternatively positioned up with palms facing down (superman) when prone.
- The front or abdomen side is anterior and the back end is posterior
- Towards the head is superior, towards the feet is inferior
- Towards the center is medial, away from the center is lateral
- Rostral is towards the superior and anterior cerebral cortex, caudal is towards the inferior and posterior spinal cord; the rostrocaudal axis runs in a line from nose to tail (rostral toward the nostril)
- Ipsilateral is the same side as a reference point, Contralateral is the opposite side of a reference point
- Proximal is closer to a reference point, Distal is further from a reference point. Example: The shoulder is proximal, the wrist is distal.
- Prone is lying on your stomach, your torso facing down
- Supine is lying on your back, your torso facing up
The Planes of Section are specified orientations for describing the nervous system in three dimensions. There are four basic reference points of the human body in three dimensional space and 90 degree references using an imaginary longitudinal axis/neuraxis that travels through the superior and inferior center, the central nervous system has a predominantly longitudinal organization. Radiological images are obtained in these planes:
- The Median/Midline Plane divides a structure along it's longitudinal/lengthwise axis symmetrically dividing the structure into left and right halves to study structures immediately adjacent to the midline
- The Sagittal Plane also runs longitudinally but parallel to the Median/Midline Plane and is often employed to study/scan internal structures for three-dimensional visualization in slices/sections
- The Coronal/Transverse Plane divides a structure perpendicular to the longitudinal axis and is often employed to study/scan internal structures for three-dimensional visualization in slices/sections. The term cross-section is also applied to transverse sections of the spinal cord and brain stem.
- The Horizontal Plane are cut in parallel to the horizon/longitudinal axis/neuraxis and is perpendicular to the Median/Sagittal/Coronal planes fand is often employed to study/scan internal structures for three-dimensional visualization in slices/sections.