Table 5.4.

Descriptive summary of Global Limb Anatomic Staging System (GLASS) stages of infrainguinal arterial disease

	Estimated PVI outcomes
Stage	Technical failure	1-year LBP	Anatomic pattern
I	<10%	>70%	Short- to intermediate-length FP disease and/or short-length IP disease; no or minimal popliteal disease
II	<20%	50%–70%	Intermediate- to long-length FP disease; may include popliteal stenosis and/or short- to intermediate-length IP disease
III	>20%	<50%	Extensive FP or IP occlusions, alone or in combination with any disease in the other segment; popliteal CTO

CTO, Chronic total occlusion; FP, femoropopliteal; IP, infrapopliteal; LBP, limb-based patency; PVI, peripheral [endo-]vascular intervention.