Table 1. Direction of displacements changes by target-centered frame-based coordinate system. MidACPC coordinate space axes are similar to CRW, Micromar, FiME, Macom, Zeppelin. However, Leksell G has flipped signs of displacement on the LAT and VERT directions, where the origin is right-posterior-superior. The CRW and Leksell G base rings are fixed inferiorly, whereas the others can be fixed additionally in a more superior position. Lastly, N-localizer dimensions are compared.

*Larger N-localizer for radiosurgery

N-localizer - see references [6-8]

mm = millimeters; AP = Antero-Posterior; LAT = Lateral; VERT = Vertical; H x W = Height and Width; MidACPC = Middle of anterior commissure and posterior commissure

CRW = Cosman-Roberts-Wells stereotactic frame, Radionics CRW Stereotactic System, Integra LifeSciences Corporation, Plainsboro, NJ, USA

Leksell G = Leksell Stereotactic Frame, Elekta, Stockholm, Sweden

Micromar Ind. Com. Ltda, Diadema, Sao Paulo, Brazil

FiMe Medica SRL, Cordoba, Argentina

Macom Instrumental Cirurgico, Sao Paulo, Brazil

Zeppelin Adeor Medical AG, Martinshof 5, D-83626 Valley, Germany

	Offset
	Origin-center	Origin-center	Origin-base				N-Localizer
Stereotactic Frame	LAT (mm)	AP (mm)	VERT (mm)	Right	Anterior	Superior	[H x W] (mm)
CRW	0	0	-86	+	+	+	189 x 140
Leksell G	100	100	160	-	+	-	120 x 120
Micromar	0	0	0	+	+	+	140 x 140 & 175 x 140*
FiMe	0	0	0	+	+	+	160 x 160 & 200 x 160*
Macom	0	0	0	+	+	+	140 x 140
Zeppelin	0	0	0	+	+	+	140 x 140