{"doi":"10.1002/mrm.29933","title":"Optimization of the flip angles of narrow‐band editing pulses in J‐difference edited <scp>MRS</scp> of lactate at <scp>3T</scp>","abstract":"PURPOSE: Application of highly selective editing RF pulses provides a means of minimizing co-editing of contaminants in J-difference MRS (MEGA), but it causes reduction in editing yield. We examined the flip angles (FAs) of narrow-band editing pulses to maximize the lactate edited signal with minimal co-editing of threonine. METHODS: The effect of editing-pulse FA on the editing performance was examined, with numerical and phantom analyses, for bandwidths of 17.6-300 Hz in MEGA-PRESS editing of lactate at 3T. The FA and envelope of 46 ms Gaussian editing pulses were tailored to maximize the lactate edited signal at 1.3 ppm and minimize co-editing of threonine. The optimized editing-pulse FA MEGA scheme was tested in brain tumor patients. RESULTS: Simulation and phantom data indicated that the optimum FA of MEGA editing pulses is progressively larger than 180° as the editing-pulse bandwidth decreases. For 46 ms long 17.6 Hz bandwidth Gaussian pulses and other given sequence parameters, the lactate edited signal was maximum at the first and second editing-pulse FAs of 241° and 249°, respectively. The edit-on and difference-edited lactate peak areas of the optimized FA MEGA were greater by 43% and 25% compared to the 180°-FA MEGA, respectively. In-vivo data confirmed the simulation and phantom results. The lesions of the brain tumor patients showed elevated lactate and physiological levels of threonine. CONCLUSION: The lactate MEGA editing yield is significantly increased with editing-pulse FA much larger than 180° when the editing-pulse bandwidth is comparable to the lactate quartet frequency width.","journal":"Magnetic Resonance in Medicine","year":2023,"id":387118,"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":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.959,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2023-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":760901,"name":"Ryan K. Robison","orcid":"0000-0002-8244-0653","position":1,"is_corresponding":false},{"id":1155937,"name":"Jie Hu","orcid":"0000-0003-4993-5758","position":2,"is_corresponding":false},{"id":793310,"name":"Saikat Sengupta","orcid":"0000-0001-5032-006X","position":3,"is_corresponding":false},{"id":1155938,"name":"Olaimatu S. Mahdi","orcid":"0000-0003-1830-5411","position":4,"is_corresponding":false},{"id":344641,"name":"Adam W. Anderson","orcid":"0000-0002-3788-6138","position":5,"is_corresponding":false},{"id":745699,"name":"Leo Y. Luo","orcid":"0000-0002-3061-4287","position":6,"is_corresponding":false},{"id":1156335,"name":"Alexander Mohler","orcid":null,"position":7,"is_corresponding":false},{"id":456436,"name":"Ryan Merrell","orcid":"0000-0002-8076-0768","position":8,"is_corresponding":false},{"id":312133,"name":"Changho Choi","orcid":"0000-0002-7135-2447","position":9,"is_corresponding":false},{"id":1156334,"name":"Jason E. Moore","orcid":null,"position":0,"is_corresponding":true}],"reference_count":15,"raw_metadata":null,"created_at":"2026-07-19T01:18:04.706547Z","pmid":"38010083","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":[]}