Table 3.

Each branch is assigned a score based on the maximal intima-media thickness (IMT) identified in that branch.

Halo score	Common STA	Frontal STA	Parietal STA	Axillary Artery
0	0–0.3	0–0.1	0–0.2	0–0.5
1	0.31–0.4	0.11–0.2	0.21–0.3	0.51–0.6
2	0.41–0.5	0.21–0.3	0.31–0.4	0.61–0.89
3	0.51–0.79	0.31–0.49	0.41–0.59	0.9–1.5
4	≥ 0.8	≥ 0.5	≥ 0.6	≥ 1.6

IMT ranges (in millimeters) and their corresponding scores are outlined. Values for axillary arteries are multiplied by three to account for it having fewer branches. The scores are added to give a Total Halo Score, with a maximum value of 48. Halo scores are evaluated on serial scans to assess for wall-thickness regression. STA, Superficial Temporal Artery (50).