A Novel Three-Dimensional Vector Analysis of Axial Globe Position in Thyroid Eye Disease

Table 1

The landmarks, reference points, and planes of the 3D coordinate system.

		Abbreviation	Definition
Landmark	Right porion	PoR	Highest midpoint on roof of the right skeletal external auditory meatus
	Left porion	PoL	Highest midpoint on roof of the left skeletal external auditory meatus
	Right orbitale	OrR	Lowest point on the right infraorbital margin
	Left orbitale	OrL	Lowest point on the left infraorbital margin
	Nasion	N	The point of contact between the frontal bone and suture between 2 halves of the nasal bones
	Sella	S	The midpoint of the pituitary fossa of the sphenoid bone
	Right lateral orbital point	LoR	The deepest point on the right lateral orbital rim
	Left lateral orbital point	LoL	The deepest point on the left lateral orbital rim
Reference point	Middle point of porion	PoM	The middle point of the right and left porion
	Middle point of orbitale	OrM	The middle point of the right and left orbitale
	Middle point of lateral orbital point	LoM	The middle point of lateral orbital point
Reference plane	Frankfort horizontal plane (xy plane)	FH plane	Passing through PoR, PoL, and OrM
	Midsagittal plane (xz plane)	MS plane	Passing through N and S and being perpendicular to the FH plane
	Coronal plane (yz plane)		Passing through LoM and orthogonal to the MS and FH plane