Table 11.

Grading intravascular filling defects (IVFD)

Lesion	Grading	Definition		Figures
Intravascular filling defects (IVFD)	Cannot grade	No gradeable images exist (adjacent capillaries are not clear). CG can be assigned to one or more vessel types		None
	Capillaries	Absent	IVFD are not seen in any capillaries	None
		Present	IVFD are seen in capillaries	None
	Post-capillary venule complex	Absent	IVFD are not seen in any post-capillary venules	None
		Present	IVFD are seen in post-capillary venules	None
	Pre-capillary arteriole complex	Absent	IVFD are not seen in any pre-capillary arterioles	None
		Present	IVFD are seen in pre-capillary arterioles	None
	Small venules	Absent	IVFD are not seen in any small venules	None
		Present	IVFD are seen in small venules	28, 29
	Small arterioles	Absent	IVFD are not seen in any small arterioles	None
		Present	IVFD are seen in small arterioles	28, 29
	Large venules	Absent	IVFD are not seen in any large venules	None
		Present	IVFD are seen in large venules	28, 29
	Large arterioles	Absent	IVFD are not seen in any large arterioles	None
		Present	IVFD are seen in large arterioles	28, 29