Anne Shu-Lei Chin MD, Presenter: Nothing to Disclose

Adrianne Kamara Thompson MD, Abstract Co-Author: Nothing to Disclose

Bruce L. Daniel MD, Abstract Co-Author: Nothing to Disclose

Robert John Herfkens MD, Abstract Co-Author: Consultant, Bracco Group, Milan, Italy

Due to recent constraints on administering gadolinium in patients with moderate renal insufficiency because of potential development of nephrogenic systemic fibrosis (NSF), there has been heightened interest in developing safe and reliable alternatives to CE-MRA. We evaluated a 3D balanced SSFP ECG-gated, respiratory-navigated MRA sequence for imaging the renal arteries without contrast medium.

Ten patients consented under an IRB-approved protocol were imaged for evaluation of renal artery stenosis using a 3D balanced SSFP ECG-gated, respiratory-navigated MRA sequence on a 1.5T MR system (Twin Speed, GE Medical Systems, Waukesha, WI). Non-contrast MRA was performed using the following parameters: TR 4.9 ms, TE 2.4 ms, FA 90 degrees, matrix 256x256, FOV 30-35 cm, BW 125 kHz, slice thickness 2.4 mm with 1.2 mm slice spacing. Multiple overlapping slabs were acquired using 20 locations per slab, a cardiac trigger delay set in mid-diastole, and a prospective respiratory navigator to image at end-expiration yielding a scan efficiency between 30-40%. Conventional CE-MRA was also performed in half the patients with the following parameters: TR 4.8 ms, TE 1.1 ms, FA 25 degrees, matrix 512x192, FOV 30-35 cm, BW 125 kHz, slice thickness 2.4 with 1.2 mm slice spacing, 0.1 mmol/kg gadolinium at 2cc/sec. Signal-to-noise ratio (SNR) was determined at predetermined regions within the main renal arteries. A subjective visual score for image quality and vessel sharpness on a scale from 1 to 4 was assessed for each region. Any artifactual degradation of image quality was also noted.

High resolution images with excellent SNR and good visibility of the main renal arteries were obtained using 3D balanced SSFP ECG-gated, respiratory-navigated MRA.

3D balanced SSFP ECG-gated, respiratory-navigated MRA is a safe and reliable alternative to CE-MRA for renal artery stenosis evaluation in patients who should not receive gadolinium due to moderate to severe renal insufficiency.

Recent association of NSF and gadolinium administration in patients with severe renal failure requires development and validation of safe and reliable non-contrast imaging alternatives.

Chin, A, Thompson, A, Daniel, B, Herfkens, R, Three-dimensional (3D) Balanced Steady State Free Precession (SSFP) ECG-Gated, Respiratory-Navigated Free-Breathing Renal MR Angiography (MRA): An Alternative to Contrast-enhanced MR Angiography (CE-MRA) in Patients with Renal Insufficiency.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5008185.html