Table 1.

Angiographic classification of Takayasu's arteritis

Type	Vessel involvement
Type I	Main branches of the aortic arch
Type IIa	Ascending aorta, aortic arch and its branches
Type IIb	Ascending aorta, aortic arch and its branches and thoracic descending aorta
Type III	Thoracic descending aorta, abdominal aorta and/or renal arteries
Type IV	Abdominal aorta and/or renal arteries
Type V	Types IIb and IV occurring together