{"doi":"10.1117/1.bios.2.3.035002","title":"Noninvasive measurements of skeletal muscle hemodynamics using frequency-domain near-infrared spectroscopy: contributions from adipose and bone tissues","abstract":"Significance: Noninvasive optical assessments of skeletal muscle perfusion and metabolism are crucial for studying muscle physiology. However, measurements can be affected by contributions from overlying adipose and underlying bone tissues. Aim: We aim to investigate the influence of bone tissue on frequency-domain near-infrared spectroscopy (FD-NIRS) measurements of the human forearm using different data types (intensity and phase), source-detector separations (25 and 37 mm), and acquisition modes (single-distance and dual-slope). Approach: findings were compared with diffusion theory simulations for two- and three-layer media. Ultrasound imaging quantified adipose tissue thickness (1.5 to 9.5 mm) and bone depth (14 to 26 mm). Results: Experimental results for bone depths below 20 mm could not be reproduced by two-layer simulations, whereas they aligned well with three-layer simulations mimicking adipose, muscle, and bone tissues. Adipose tissue and bone contributions depend on data type, measurement mode, and source-detector separation. Conclusions: Both adipose and bone tissues may contribute to noninvasive FD-NIRS measurements of skeletal muscle, depending on tissue anatomy and data collection methods.","journal":"Biophotonics discovery.","year":2025,"id":575105,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9599,"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":270601,"name":"Angelo Sassaroli","orcid":"0000-0003-4233-7165","position":1,"is_corresponding":false},{"id":1115477,"name":"Jodee Frias","orcid":"0000-0002-2626-9441","position":2,"is_corresponding":false},{"id":409629,"name":"Giles Blaney","orcid":"0000-0003-3419-4547","position":3,"is_corresponding":false},{"id":270600,"name":"Sergio Fantini","orcid":"0000-0001-5116-525X","position":4,"is_corresponding":false},{"id":1120086,"name":"Fatemeh Tavakoli","orcid":"0000-0003-3792-455X","position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-19T02:57:48.486077Z","pmid":"42028252","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":[]}