{"doi":"10.1002/mp.14947","title":"Technical Note: Quantification of blood‐spinal cord barrier permeability after application of magnetic resonance‐guided focused ultrasound in spinal cord injury","abstract":"PURPOSE: To demonstrate that magnetic resonance-guided focused ultrasound (MRgFUS) facilitates blood-spinal cord barrier (BSCB) permeability and develop observer-independent MRI quantification of BSCB permeability after MRgFUS for spinal cord injury (SCI). METHODS: Noninjured Sprague-Dawley rats (n = 3) underwent MRgFUS and were administered Evans blue post-MRgFUS to confirm BSCB opening. Absorbance was measured by spectrophotometry and correlated with its corresponding image intensity. Rats (n = 21) underwent T8-T10 laminectomy and extradural compression of the spinal cord (23g weighted aneurysm-type clip, 1 min). The intervention group (n = 11) was placed on a preclinical MRgFUS system, administered microbubbles (Optison, 0.2 mL/kg), and received 3 MRgFUS sonications (25 ms bursts, 1 Hz pulses for 3 min, 3 acoustic W, approximately 1.0-2.1 MPa peak pressure as measured via hydrophone). The sham group (n = 10) received equivalent procedures with no sonications. T1w MRI was obtained both pre- and post-MRgFUS BSCB opening. Spinal cords were segmented manually or semiautomatically and a Pearson correlation with P ≤ 0.001 was used to correlate the two segmentation methods. MRgFUS sonication and control regions intensity values were evaluated with a paired t-test with a P ≤ 0.01. RESULTS: Semiautomatic segmentation reduced computational time by 95% and was correlated with manual segmentation (Pearson = 0.92, P < 0.001, n = 71 regions). In the noninjured rat group, Evans blue absorbance correlated with image intensity in the MRgFUS and control regions (Pearson = 0.82, P = 0.02, n = 6). In rats that underwent the SCI procedure, an increase in signal intensity in the MRgFUS targeted region relative to control was seen in all SCI rats (10.65 ± 12.4%, range: 0.96-43.9%, n = 11, P = 0.002). SCI sham MRgFUS revealed no change (0.63 ± 0.52%, 95% CI 0.320.95, n = 10). This result was significant between both groups (P = 0.003). CONCLUSION: The implemented semiautomatic segmentation procedure improved data analysis efficiency. Quantitative methods using contrast-enhanced MRI with histological validation are sensitive for detection of blood-spinal cord barrier opening induced by magnetic resonance-guided focused ultrasound.","journal":"Medical Physics","year":2021,"id":190911,"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":13,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9372,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":388329,"name":"Allison Payne","orcid":"0000-0002-7724-5001","position":1,"is_corresponding":false},{"id":755732,"name":"Gregory W. J. Hawryluk","orcid":"0000-0002-5604-7057","position":2,"is_corresponding":false},{"id":756512,"name":"Riley Haag‐Roeger","orcid":null,"position":3,"is_corresponding":false},{"id":756513,"name":"Rahul Cheeniyil","orcid":null,"position":4,"is_corresponding":false},{"id":756514,"name":"Dalton Brady","orcid":null,"position":5,"is_corresponding":false},{"id":388327,"name":"Henrik Odéen","orcid":"0000-0003-2055-9795","position":6,"is_corresponding":false},{"id":751484,"name":"Satoshi Minoshima","orcid":"0000-0002-0043-3047","position":7,"is_corresponding":false},{"id":388366,"name":"Donna J. Cross","orcid":"0000-0003-1918-2214","position":8,"is_corresponding":false},{"id":441764,"name":"Yoshimi Anzai","orcid":"0000-0003-2988-7445","position":9,"is_corresponding":false},{"id":755731,"name":"Chloe G. Cross","orcid":"0000-0001-5596-8981","position":0,"is_corresponding":true}],"reference_count":32,"raw_metadata":null,"created_at":"2026-07-18T23:49:31.121780Z","pmid":"33999427","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":[]}