The most frequent finding of EIAE at DSA is smooth, long, and eccentric stenosis, with thrombosis and dissection present less frequently [1]. Although the external iliac artery is most frequently affected, the common iliac artery can be involved in approximately 15% of patients [32]. A benefit of arteriography, relative to other modalities, is that the pressure gradient across the narrowing can be measured at baseline as well as during various maneuvers, including following the administration of vasodilators [33]. Acquiring images during hip flexion frequently reveals a kink in the iliac arteries at the site of stenosis [32]. Variant 3: Suspected or known lower-extremity inflammatory vasculitides. Initial imaging. CTA Lower Extremity While the spatial resolution of CTA is relatively high, some authors have suggested that it may not be sensitive enough to resolve the fine collateral vessels seen in thromboangiitis obliterans and other small-vessel pathologies [2]. Evaluation of subtle vascular findings may also be limited by beam hardening artifact related to adjacent bone or metal [34]. CTA is helpful in identifying vessel wall thickening, stenosis, occlusion and collaterals when large- or medium-sized vessels of the lower extremities are involved. MRA Lower Extremity MRA has lower spatial resolution than CTA, a factor that makes it less than ideal in adequately characterizing distal small vessels. Despite this, additional sequences acquired during an MRA examination may be helpful in evaluating for associated nonvascular findings, such as osteomyelitis or septic arthritis [2]. The sensitivity for detecting these soft-tissue abnormalities is greater with contrast-enhanced MRA than noncontrast-enhanced MRA. Arteriography Lower Extremity Because of its high inherent spatial resolution, selective arteriography with DSA is considered the gold standard in the diagnosis of thromboangiitis obliterans [2].
Nonatherosclerotic Peripheral Arterial Disease. The most frequent finding of EIAE at DSA is smooth, long, and eccentric stenosis, with thrombosis and dissection present less frequently [1]. Although the external iliac artery is most frequently affected, the common iliac artery can be involved in approximately 15% of patients [32]. A benefit of arteriography, relative to other modalities, is that the pressure gradient across the narrowing can be measured at baseline as well as during various maneuvers, including following the administration of vasodilators [33]. Acquiring images during hip flexion frequently reveals a kink in the iliac arteries at the site of stenosis [32]. Variant 3: Suspected or known lower-extremity inflammatory vasculitides. Initial imaging. CTA Lower Extremity While the spatial resolution of CTA is relatively high, some authors have suggested that it may not be sensitive enough to resolve the fine collateral vessels seen in thromboangiitis obliterans and other small-vessel pathologies [2]. Evaluation of subtle vascular findings may also be limited by beam hardening artifact related to adjacent bone or metal [34]. CTA is helpful in identifying vessel wall thickening, stenosis, occlusion and collaterals when large- or medium-sized vessels of the lower extremities are involved. MRA Lower Extremity MRA has lower spatial resolution than CTA, a factor that makes it less than ideal in adequately characterizing distal small vessels. Despite this, additional sequences acquired during an MRA examination may be helpful in evaluating for associated nonvascular findings, such as osteomyelitis or septic arthritis [2]. The sensitivity for detecting these soft-tissue abnormalities is greater with contrast-enhanced MRA than noncontrast-enhanced MRA. Arteriography Lower Extremity Because of its high inherent spatial resolution, selective arteriography with DSA is considered the gold standard in the diagnosis of thromboangiitis obliterans [2].