{"doi":"10.1186/s13014-024-02499-2","title":"Inversion-recovery ultrashort-echo-time (IR-UTE) MRI-based detection of radiation dose heterogeneity in gynecologic cancer patients treated with HDR brachytherapy","abstract":"Abstract Purpose To evaluate the relationship between delivered radiation (RT) and post-RT inversion-recovery ultrashort-echo-time (IR-UTE) MRI signal-intensity (SI) in gynecologic cancer patients treated with high-dose-rate (HDR) brachytherapy (BT). Methods Seven patients underwent whole-pelvis RT (WPRT) followed by BT to the high-risk clinical target volume (HR-CTV). MR images were acquired at three time-points; pre-RT, post-WPRT/pre-BT, and 3–6 months post-BT. Diffuse-fibrosis (F Diffuse ) was imaged with a non-contrast dual-echo IR (inversion time [TI] = 60 ms) UTE research application, with image-subtraction of the later echo, only retaining the ultrashort-echo SI. Dense-fibrosis (F Dense ) imaging utilized single-echo Late-Gadolinium-Enhanced IR-UTE, acquired ∼ 15 min post-Gadavist injection. Resulting F Diffuse and F Dense SI were normalized to the corresponding gluteal-muscle SI. Images were deformably registered between time-points based on normal tissue anatomy. The remnant tumor at both time-points was segmented using multi-parametric MRI. Contours corresponding to the 50%, 100%, 150%, and 200% isodose lines (IDLs) of the prescription BT-dose were created. Mean F Diffuse and F Dense SI within (i) each IDL contour and (ii) the remnant tumor were calculated. Post-BT F Diffuse and F Dense SI were correlated with prescribed BT-dose. To determine the relationship between BT-dose and IR-UTE SI, the differences in the post-BT F Dense across IDLs was determined using paired t-tests with Bonferroni correction. Results F Dense was higher in regions of higher dose for 6/7 patients, with mean ± SD values of 357 ± 103% and 331 ± 97% ( p = .03) in the 100% and 50% IDL, respectively. F Dense was higher in regions of higher dose in the responsive regions with mean ± SD values of 380 ± 122% and 356 ± 135% ( p = .03) in the 150% and 50% IDL, respectively. Within the segmented remnant tumor, an increase in prescribed dose correlated with an increase in F Dense post-BT ( n = 5, r = .89, p = .04). Post-BT F Diffuse inversely correlated ( n = 7, r = -.83, p = .02) with prescribed BT-dose within the 100% IDL. Conclusions Results suggest that F Dense SI 3–6 months post-BT is a sensitive measure of tissue response to heterogeneous BT radiation-dose. Future studies will validate whether F Diffuse and F Dense are accurate biomarkers of fibrotic radiation response.","journal":"Radiation Oncology","year":2024,"id":466111,"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":4,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9611,"is_data_producer":false,"deposit_databanks":null,"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":461270,"name":"Bruce L. Daniel","orcid":"0000-0003-0475-5892","position":1,"is_corresponding":false},{"id":1297903,"name":"Michael Roumeliotis","orcid":"0000-0003-2429-0690","position":2,"is_corresponding":false},{"id":705077,"name":"Junghoon Lee","orcid":"0000-0002-3004-8625","position":3,"is_corresponding":false},{"id":1229637,"name":"William T. Hrinivich","orcid":"0000-0002-0048-9411","position":4,"is_corresponding":false},{"id":480638,"name":"Thomas Benkert","orcid":"0000-0002-3794-5580","position":5,"is_corresponding":false},{"id":671942,"name":"Himanshu Bhat","orcid":"0000-0002-2503-2207","position":6,"is_corresponding":false},{"id":443974,"name":"Ravi T. Seethamraju","orcid":"0000-0002-2719-6854","position":7,"is_corresponding":false},{"id":402669,"name":"Akila Viswanathan","orcid":"0000-0002-0007-2296","position":8,"is_corresponding":false},{"id":705076,"name":"Ehud J. Schmidt","orcid":"0000-0002-5792-2087","position":9,"is_corresponding":false},{"id":1029580,"name":"Khadija Sheikh","orcid":"0000-0002-1168-1783","position":0,"is_corresponding":true}],"reference_count":29,"raw_metadata":null,"created_at":"2026-07-19T02:04:54.606394Z","pmid":"39107776","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":[]}