Value of MR and CT Imaging for Assessment of Internal Carotid Artery Encasement in Head and Neck Squamous Cell Carcinoma

Table 1

Radiologically determined criteria and interobserver kappa.

Radiologically determined criteria	Observer 1 N = 12	Observer 2 N = 12	Interobserver kappa
Encasement			0.584
<180 degrees	2 (17%)	0 (0%)
180–270 degrees	0 (0%)	4 (33%)
>270 degrees	10 (83%)	8 (67%)
Obliteration of fat planes			1
No	0	0
Yes	12 (100%)	12 (100%)
Deformation of the carotid artery			0.273
No	4 (33%)	2 (17%)
Yes	8 (67%)	10 (83%)
Length of contact carotid artery			0.488
Mean in cm	3.5 (range: 1.0–5.0; SD 1.3)	3.6 (range: 1.6–6.1; SD 1.6)