A B C D E F G H J K L P Q R S T U V
A2 A3 A4 A5 A6 A7 A8 A9 Aa Ad Ae Af Ag Ah Aj Ak Am Ar At Au Av Aw Ax

AT

HCPCS Level II modifier that may be used with CPT or HCPCS Level II codes indicating acute treatment services.