Table 1.

A comparative list of some of the characteristics of the two MLCs. Both the 160 MLC and the 120 MLC are in clinical use in our department.

	160 MLC on ARTISTE	120 MLC on 2300 EX
Source collimator distance	460 mm	535 mm
Patient clearance	430 mm	334 mm
Leaf resolution	5 mm leaf entire 40 cm field	5 mm central 40 leaves and 10 mm remaining outer leaf
Leaf End	S‐shaped	C‐shaped
Leaf height	95 mm	55 mm
Penumbra (80 ‐ 20%)	3.6 mm	3.2 mm
Leakage and transmission	0.37%	2.00%
Inter‐digitization	Yes	Yes
Method to avoid a direct ray in between leaves	Tilted alternating pattern of upper and lower leaf	tongue and groove
Max Leaf Speed	$40{\text{mms}}^{-1}$	$20{\text{mms}}^{-1}$
Leaf Span	200 mm	145 mm
Step and shoot IMRT	Yes	Yes
Dynamic IMRT	No	Yes