23
Imaging Parameters
Entry flow into the false lumen:
• Presence and locations of any entry flow
• Use the following classification system for describing flow to the false lumen:
▶ Type IA entry flow: proximal perigraft entry flow—flow between the proximal
endograft and aortic wall allowing systemic pressure antegrade flow into the
primary entry tear and proximal false lumen (Figure 16, A).
▶ Type IB entry flow: distal perigraft entry flow—distal entry tear adjacent to
endograft due to septal fenestration or a new intimal tear at the distal aspect of
the stent graft (SINE) allowing systemic pressure direct flow into the false lumen
(Figure 16, B).
▶ Type II entry flow: retrograde entry flow through arch vessel branches
(innominate, carotid, subclavian) or thoracic bronchial and intercostal arteries into
the false lumen (Figure 16, C).
▶ Type R entry flow: antegrade entry flow from the true lumen into the false lumen
through distal branch fenestrations (uncovered intercostal arteries, visceral or renal
arteries, lumbar arteries, iliac branches) or septal fenestrations (not including SINE
adjacent to the distal endograft, which is type IB; Figure 16, D).
oracic stent gra:
• CTA changes in morpholog y
▶ "bird-beaking" of the proximal segment
▶ collapse
▶ stent fracture
▶ any migration of stent grafts
