Unenhanced respiratory-navigated NATIVE® TrueFISP magnetic resonance angiography in the evaluation of renal arteries: Comparison with contrast-enhanced magnetic resonance angiography.

PURPOSE: To compare unenhanced three-dimensional (3D) NATIVE® true fast imaging with steady-state precession (TrueFISP) magnetic resonance (MR) angiography with the more conventional MR angiography technique obtained after intravenous administration of a gadolinium chelate in the evaluation of renal arteries and their branches in patients with suspected renal artery stenosis. MATERIALS AND METHODS: A total of 39 patients (25 men, 14 women) with a mean age of 51.4±17.5years (SD) (range: 10-82years) were included in the study. All patients with suspected renal artery stenosis underwent unenhanced 3D NATIVE® TrueFISP MR angiography and contrast-enhanced MR angiography. The two MR angiography methods were compared by two independent readers for image quality using a four-point scale, diagnostic performance and grading of renal artery stenosis on a total of 78 renal arteries. RESULTS: For both readers image quality of unenhanced 3D NATIVE® TrueFISP MR angiography (3.12 to 3.63) was greater than that of contrast-enhanced MR angiography (1.94 to 2.71) for renal artery ostium-trunk and the left renal artery segmental branches. The sensitivity of 3D NATIVE® TrueFISP MR angiography for the diagnosis of renal artery stenosis was 100% for both readers for the right renal artery and 66% and 80% for the left renal artery for reader 1 and reader 2, respectively. Agreement between 3D NATIVE® TrueFISP MR angiography and CE-MR angiography was 95% (74/78) for reader 1 and 92% (72/78) for reader 2. CONCLUSION: Unenhanced NATIVE® TrueFISP magnetic resonance angiography can play an additional role in the evaluation of renal arteries in patients with hypertension, especially in subjects at risk of nephrogenic systemic fibrosis.

Anatomic variations of popliteal artery: Evaluation with 128-section CT-angiography in 1261 lower limbs.

PURPOSE: The purpose of this study was to evaluate the variations in popliteal artery branching in a large population on computed tomography angiography (CTA) using a 128-section configuration. MATERIALS AND METHODS: A total of 652 patients (532 men, 120 women) with a mean age of 61.7±18.1 (SD) years (range: 11-93 years) who had CTA of the lower limbs with a total of 1261 lower limbs (bilateral limbs in 609 patients, unilateral limb in 43 patients) were retrospectively included. CTA images were reviewed for popliteal artery branching and possible variations. RESULTS: The usual pattern of popliteal artery branching was observed in 1118 limbs (88.7%) (type IA) whereas branching variations without the usual pattern were found in 143 limbs (11.3%). Forty limbs (3.2%) were categorized as type I with non-classical patterns. Forty limbs (3.2%) showed type II high-level bifurcation and 63 limbs (4.9%) showed type III aplasia or hypoplasia. The type IIC pattern was not observed. Importantly, one single case considered as hypoplasia of the peroneal artery and another case identified with a long tibioperoneal artery were categorized into new subgroups. CONCLUSIONS: Recognizing and evaluating variations in popliteal artery branches is important in terms of vascular surgery approaches and interventional vascular procedures. CTA is an effective screening method to show the vascular frame of lower extremities and variations of popliteal artery. Our study allowed identifying two new branching patterns of the popliteal artery not previously described in the literature.