{"doi":"10.1002/jmri.70033","title":"Motion‐Insensitive Flip Angle Modulated Liver Proton Density Fat‐Fraction and <scp>R2</scp>* Mapping During Free‐Breathing <scp>MRI</scp> in a Clinical Setting","abstract":"ABSTRACT Background Breath‐held quantitative three‐dimensional chemical‐shift‐encoded (3D‐CSE)‐MRI is widely used for liver fat and iron quantification but is limited in patients unable to hold breath. Motion‐insensitive two‐dimensional flip angle modulated (2D‐FAM) acquisitions with short temporal aperture may address this limitation. Purpose To evaluate the performance of 2D‐FAM‐based CSE‐MRI during free‐breathing for quantifying proton density fat‐fraction (PDFF) and R2*‐based liver iron concentration (LIC). Study Type Retrospective single‐center observational analysis. Population 230 patients (110 women [47.8%], mean age 51 ± 16 years [standard deviation, SD], range 4–85), undergoing routine clinical care between January and August 2024. Field Strength/Sequence 1.5‐T and 3.0‐T, comparison of 2D‐FAM‐CSE‐MRI under free‐breathing and breath‐held 3D‐CSE‐MRI. Assessment Three radiologists evaluated image quality, apparent signal‐to‐noise ratio (SNR), and motion artifacts on a 5‐point scale. PDFF and R2*‐based LIC were measured in each liver segment from each acquisition. Agreement of PDFF and LIC between techniques was assessed, comparing body mass index (BMI) groups (&lt; 30 and ≥ 30 kg/m 2 ). Inter‐rater reliability was assessed for all analyses. Statistical Tests Inter‐rater reliability with intra‐class coefficient (ICC). Bias and limits of agreement (LoA) using Bland–Altman analysis. Linear regression assessed correlations of PDFF and LIC. Receiver operating characteristic (ROC) curves (AUC) to assess diagnostic performance. Statistical significance was set at p &lt; 0.05 (Bonferroni‐corrected p &lt; 0.01 for patient characteristics). Results 2D‐FAM demonstrated superior image quality (median rating 4 vs. 3) and fewer motion artifacts (median rating 4 vs. 3) than 3D‐CSE‐MRI in PDFF and R2* maps. Inter‐rater reliability was good to excellent (ICC 0.77–0.92). PDFF agreement was excellent (bias: +0.32%, LoA [−1.37,2.00] for BMI &lt; 30 kg/m 2 ; +0.66%, [−2.44,3.76] for BMI ≥ 30 kg/m 2 ). LIC agreement was high (bias: −0.02 mg/g, [−0.22,0.18]) up to a threshold of 7.0 mg/g. ROC analysis showed AUC up to 1.00 for PDFF and LIC thresholds. Data Conclusion 2D‐FAM CSE‐MRI enables motion‐insensitive liver fat and iron quantification that can be performed during free‐breathing. Evidence Level 2. Technical Efficacy Stage 2.","journal":"Journal of Magnetic Resonance Imaging","year":2025,"id":517545,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":8,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9587,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1383862,"name":"Jiayi Tang","orcid":"0009-0000-8565-6575","position":1,"is_corresponding":false},{"id":932850,"name":"Daiki Tamada","orcid":"0000-0003-3615-459X","position":2,"is_corresponding":false},{"id":59457,"name":"Lukas Müller","orcid":"0000-0002-8626-4044","position":3,"is_corresponding":false},{"id":1383863,"name":"Jan‐Peter Grunz","orcid":"0000-0002-4524-1620","position":4,"is_corresponding":false},{"id":1276877,"name":"Raphael do Vale Souza","orcid":null,"position":5,"is_corresponding":false},{"id":1383864,"name":"Alexandra Anagnostopoulos","orcid":"0009-0003-3362-9673","position":6,"is_corresponding":false},{"id":732412,"name":"Ali Pirasteh","orcid":"0000-0003-0797-4636","position":7,"is_corresponding":false},{"id":267619,"name":"Scott B. Reeder","orcid":"0000-0003-4728-8171","position":8,"is_corresponding":false},{"id":388084,"name":"Diego Hernando","orcid":"0000-0002-0016-0317","position":9,"is_corresponding":false},{"id":1383861,"name":"Julius F. Heidenreich","orcid":"0000-0002-0683-7982","position":0,"is_corresponding":true}],"reference_count":50,"raw_metadata":null,"created_at":"2026-07-19T02:48:59.410472Z","pmid":"40650546","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}