Comparison of navigator-gated and breath-held image acquisition techniques for multi-echo quantitative dixon imaging of the liver in children and young adults

Journal Article · Sat Jun 15 04:00:00 EDT 2019 · Abdominal Radiology (Online)

DOI:https://doi.org/10.1007/S00261-019-01960-1· OSTI ID:22922995

Gilligan, Leah A.; Dillman, Jonathan R.; Tkach, Jean A.

Purpose: Acquired over a breath hold, multi-echo Dixon (mDixon) magnetic resonance imaging (MRI) of the liver can be used to quantify proton density fat fraction (PDFF) and iron-related signal decay. However, young, obese, and co-morbid patients may have limited breath holding capacity and could benefit from a motion-robust mDixon acquisition. The purpose of this study was to compare hepatic PDFF and R2* values between navigator-gated and breath-held mDixon MRI acquisition techniques in children and young adults with suspected liver disease. Materials and methods: This retrospective study was institutional review board-approved with a waiver of informed consent. Patients who underwent liver MRI with breath-held and navigator-gated mDixon sequences between January 2017 and July 2018 were included. One reviewer, blinded to sequence, measured PDFF and R2* on four images from each sequence. Another blinded reviewer graded respiratory motion (5-point Likert scale). Pearson correlation (r), Lin’s concordance coefficients (r{sub c}), and Bland–Altman analyses were used to assess agreement between techniques. Frequency of clinically limiting motion (score ≥ 3) was compared with Fisher’s exact test. Results: Forty-two patients were included (15 female, 27 male; mean age: 15.7 ± 4.6 years). Mean PDFF and R2* were 16.6 ± 13.1% and 29.3 ± 4.7 s{sup −1} (breath-held) versus 17.0 ± 13.2% and 29.6 ± 5.2 s{sup −1} (navigator-gated). PDFF agreed almost perfectly between sequences (r{sub c} = 0.997, 95% CI 0.994–0.998; mean bias: 0.3%; 95% limits of agreement: − 2.4 to +1.7%), while R2* values correlated very strongly but with poor agreement (r = 0.837, r{sub c} = 0.832, 95% CI 0.716–0.910). Navigator-gated images exhibited significantly higher frequency of clinically limiting respiratory motion (88% vs. 48%, p = 0.0001). Conclusion: Despite greater respiratory motion artifact, a free-breathing navigator-gated mDixon sequence produces PDFF values with almost perfect agreement to a breath-held sequence.

• OSTI ID: 22922995
• Journal Information: Abdominal Radiology (Online), Journal Name: Abdominal Radiology (Online) Journal Issue: 6 Vol. 44; ISSN 2366-0058
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ADULTS
CHILDREN
DISEASES
FATS
IRON
LIVER
NMR IMAGING
PATIENTS
PEDIATRICS
PROTON DENSITY
RESPIRATION
REVIEWS