Ryutaro Matsuura MSc, Presenter: Nothing to Disclose

Yuichi Omura, Abstract Co-Author: Nothing to Disclose

Noriaki Akagi BS, Abstract Co-Author: Toshihide Itoh is employee of Siemens Healthcare.

Sachiko Goto PhD, Abstract Co-Author: Nothing to Disclose

Yoshiharu Azuma PhD, Abstract Co-Author: Nothing to Disclose

Shuhei Sato MD, PhD, Abstract Co-Author: Nothing to Disclose

Seiji Tahara, Abstract Co-Author: Nothing to Disclose

The delayed myocardial enhancement on MRI is preferred sequence in order to evaluate state of myocardium. However it is not yet performed to a sedated infant with congenital heart disease who has high heart rate and small myocardium since it requires suspended respiration. In this study, we validate a navigator echo triggered sequence that drives the magnetization before cardiac gated inversion recovery-T1 turbo field echo (IR-T1TFE) acquisition in the sedated free breathing pediatric population.

Cardiac MRI was performed with clinical trial on 24 sedated infants with single ventricle (female: 11, male: 13) ranged in age from 0 to 5 years (mean age: 2.3 years). The Gadoteridol (0.4ml/kg) was injected into them as the contrast media. Imaging (Figure 1) was performed on a 1.5T MR scanner (Phillips Achieva 1.5T). To compare image quality, we calculated the signal to noise ratio (SNR) and contrast to noise ratio (CNR) of two image groups which were obtained by using respiratory triggering with navigator echo and without navigator echo. Wilcoxon signed rank test was performed to compare the significant difference among two image groups at each result. Furthermore, all the images were visually assessed by 2 radiologists who are specialist of cardiac MRI.

The SNR with navigator echo was higher than without navigator echo. The CNR shows no significant difference. The visual assessment scores with navigator echo were consistently better than without navigator echo. The high spatial resolution and low noise for a clinical image is required in order to diagnose, especially in the case of an infant cardiac MRI. In this study, free breathing navigator echo has the advantage which decreases the motion artifact caused by respiration. It brings the improvement of the noise and spatial resolution for a clinical image.

Cardiac gated IR-T1FFE sequence for free breathing and using navigator echo triggered respiration allows clinically diagnostic images in sedated infants with improvement of the noise and spatial resolution for a clinical image.

Free breathing navigator echo triggered respiration IR–T1FFE allows diagnostic image in sedated infant with improved good SNR and spatial resolution.

Matsuura, R, Omura, Y, Akagi, N, Goto, S, Azuma, Y, Sato, S, Tahara, S, Clinical Validation of Using Free Breathing Navigator Echo and Triggered Cardiac Gated Delayed Myocardial Enhancement MR Imaging in Sedated Infants.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018538.html