{"doi":"10.1002/mrm.29462","title":"Self‐calibrated through‐time spiral <scp>GRAPPA</scp> for real‐time, free‐breathing evaluation of left ventricular function","abstract":"PURPOSE: Through-time spiral GRAPPA is a real-time imaging technique that enables ungated, free-breathing evaluation of the left ventricle. However, it requires a separate fully-sampled calibration scan to calculate GRAPPA weights. A self-calibrated through-time spiral GRAPPA method is proposed that uses a specially designed spiral trajectory with interleaved arm ordering such that consecutive undersampled frames can be merged to form calibration data, eliminating the separate fully-sampled acquisition. THEORY AND METHODS: The proposed method considers the time needed to acquire data at all points in a GRAPPA calibration kernel when using interleaved arm ordering. Using this metric, simulations were performed to design a spiral trajectory for self-calibrated GRAPPA. Data were acquired in healthy volunteers using the proposed method and a comparison electrocardiogram-gated and breath-held cine scan. Left ventricular functional values and image quality are compared. RESULTS: A 12-arm spiral trajectory was designed with a temporal resolution of 32.72 ms/cardiac phase with an acceleration factor of 3. Functional values calculated using the proposed method and the gold-standard method were not statistically significantly different (paired t-test, p < 0.05). Image quality ratings were lower for the proposed method, with statistically significantly different ratings (Wilcoxon signed rank test, p < 0.05) for two of five image quality aspects rated (level of artifact, blood-myocardium contrast). CONCLUSIONS: A self-calibrated through-time spiral GRAPPA reconstruction can enable ungated, free-breathing evaluation of the left ventricle in 71 s. Functional values are equivalent to a gold-standard cine technique, although some aspects of image quality may be inferior due to the real-time nature of the data collection.","journal":"Magnetic Resonance in Medicine","year":2022,"id":281703,"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":0.9527,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":926578,"name":"James Ahad","orcid":"0000-0003-2415-2343","position":1,"is_corresponding":false},{"id":379445,"name":"Yuchi Liu","orcid":"0000-0003-3533-1697","position":2,"is_corresponding":false},{"id":478977,"name":"Alexander Fyrdahl","orcid":"0000-0003-0237-7699","position":3,"is_corresponding":false},{"id":956927,"name":"William Truesdell","orcid":"0000-0001-6229-9595","position":4,"is_corresponding":false},{"id":325702,"name":"Jesse Hamilton","orcid":"0000-0002-4463-481X","position":5,"is_corresponding":false},{"id":325704,"name":"Nicole Seiberlich","orcid":"0000-0002-8356-5407","position":6,"is_corresponding":false},{"id":572674,"name":"Dominique Franson","orcid":"0000-0002-9870-3147","position":0,"is_corresponding":true}],"reference_count":33,"raw_metadata":null,"created_at":"2026-07-19T00:29:11.698554Z","pmid":"36198001","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":[]}