{"doi":"10.1002/mrm.30158","title":"GABA‐edited MEGA‐PRESS at 3 T: Does a measured macromolecule background improve linear combination modeling?","abstract":"PURPOSE: The J-difference edited γ-aminobutyric acid (GABA) signal is contaminated by other co-edited signals-the largest of which originates from co-edited macromolecules (MMs)-and is consequently often reported as \"GABA+.\" MM signals are broader and less well-characterized than the metabolites, and are commonly approximated using a Gaussian model parameterization. Experimentally measured MM signals are a consensus-recommended alternative to parameterized modeling; however, they are relatively under-studied in the context of edited MRS. METHODS: To address this limitation in the literature, we have acquired GABA-edited MEGA-PRESS data with pre-inversion to null metabolite signals in 13 healthy controls. An experimental MM basis function was derived from the mean across subjects. We further derived a new parameterization of the MM signals from the experimental data, using multiple Gaussians to accurately represent their observed asymmetry. The previous single-Gaussian parameterization, mean experimental MM spectrum and new multi-Gaussian parameterization were compared in a three-way analysis of a public MEGA-PRESS dataset of 61 healthy participants. RESULTS: Both the experimental MMs and the multi-Gaussian parameterization exhibited reduced fit residuals compared to the single-Gaussian approach (p = 0.034 and p = 0.031, respectively), suggesting they better represent the underlying data than the single-Gaussian parameterization. Furthermore, both experimentally derived models estimated larger MM fractional contribution to the GABA+ signal for the experimental MMs (58%) and multi-Gaussian parameterization (58%), compared to the single-Gaussian approach (50%). CONCLUSIONS: Our results indicate that single-Gaussian parameterization of edited MM signals is insufficient and that both experimentally derived GABA+ spectra and their parameterized replicas improve the modeling of GABA+ spectra.","journal":"Magnetic Resonance in Medicine","year":2024,"id":448725,"datarank":0.2952897863004069,"base_score":1.791759469228055,"endowment":1.791759469228055,"self_citation_contribution":0.26876392038420827,"citation_network_contribution":0.026525865916198668,"self_endowment_contribution":0.26876392038420827,"citer_contribution":0.026525865916198668,"corpus_percentile":null,"corpus_rank":null,"citation_count":5,"citer_count":5,"citers_with_citation_signal":2,"citers_with_endowment":2,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.8939,"is_data_producer":true,"deposit_databanks":{"Dataset DOI":["DOI: 10.17605/OSF.IO/QD37B"]},"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":238011,"name":"Helge J. Zöllner","orcid":"0000-0002-7148-292X","position":1,"is_corresponding":false},{"id":691233,"name":"Dunja Simičić","orcid":"0000-0002-6600-2696","position":2,"is_corresponding":false},{"id":238012,"name":"Steve C. N. Hui","orcid":"0000-0002-1523-4040","position":3,"is_corresponding":false},{"id":417910,"name":"Yulu Song","orcid":"0000-0002-4416-7959","position":4,"is_corresponding":false},{"id":311506,"name":"Kathleen E. Hupfeld","orcid":"0000-0001-5086-4841","position":5,"is_corresponding":false},{"id":459004,"name":"James J. Prisciandaro","orcid":"0000-0002-8877-7871","position":6,"is_corresponding":false},{"id":238015,"name":"Richard A.E. Edden","orcid":"0000-0002-0671-7374","position":7,"is_corresponding":false},{"id":238010,"name":"Georg Oeltzschner","orcid":"0000-0003-3083-9811","position":8,"is_corresponding":false},{"id":664556,"name":"Christopher W. Davies‐Jenkins","orcid":"0000-0002-6015-762X","position":0,"is_corresponding":true}],"reference_count":66,"raw_metadata":null,"created_at":"2026-07-19T02:02:12.215092Z","pmid":"38818623","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":[]}