Quantification of H217O by 1H-MR imaging at 3 T: a feasibility study

European Radiology Experimental

Luis Martí-Bonmatí¹  Amadeo Ten-Esteve¹  Alejandro Rodríguez-Ortega¹  Ángel Alberich-Bayarri²  Bernardo Celda³  Eduardo Ferrer⁴ 

[1] Biomedical Imaging Research Group (GIBI230) at La Fe Health Research Institute and Imaging La Fe node at Distributed Network for Biomedical Imaging (ReDIB) Unique Scientific and Technical Infrastructures (ICTS), La Fe University and Polytechnic Hospital, Av. Fernando Abril Martorell, 106, Torre E, Planta 0, 46026, Valencia, Spain;Biomedical Imaging Research Group (GIBI230) at La Fe Health Research Institute and Imaging La Fe node at Distributed Network for Biomedical Imaging (ReDIB) Unique Scientific and Technical Infrastructures (ICTS), La Fe University and Polytechnic Hospital, Av. Fernando Abril Martorell, 106, Torre E, Planta 0, 46026, Valencia, Spain;Quantitative Imaging Biomarkers in Medicine, QUIBIM SL, Valencia, Spain;Physical Chemistry Department, University of Valencia, Valencia, Spain;Radiotherapy Department, Hospital Clínico Universitario, Valencia, Spain;

关键词: Brain;    Magnetic resonance imaging;    Oxygen-17;    Phantoms (imaging);    Rats;   

DOI  :  10.1186/s41747-021-00246-w

来源: Springer

【 摘 要 】

BackgroundIndirect 1H-magnetic resonance (MR) imaging of 17O-labelled water allows imaging in vivo dynamic changes in water compartmentalisation. Our aim was to describe the feasibility of indirect 1H-MR methods to evaluate the effect of H217O on the MR relaxation rates by using conventional a 3-T equipment and voxel-wise relaxation rates.MethodsMR images were used to calculate the R1, R2, and R2* relaxation rates in phantoms (19 vials with different H217O concentrations, ranging from 0.039 to 5.5%). Afterwards, an experimental animal pilot study (8 rats) was designed to evaluate the in vivo relative R2 brain dynamic changes related to the intravenous administration of 17O-labelled water in rats.ResultsThere were no significant changes on the R1 and R2* values from phantoms. The R2 obtained with the turbo spin-echo T2-weighted sequence with 20-ms echo time interval had the higher statistical difference (0.67 s−1, interquartile range 0.34, p < 0.001) and Spearman correlation (rho 0.79). The R2 increase was adjusted to a linear fit between 0.25 and 5.5%, represented with equation R2 = 0.405 concentration + 0.3215. The highest significant differences were obtained for the higher concentrations (3.1–5.5%). The rat brain MR experiment showed a mean 10% change in the R2 value after the H217O injection with progressive normalisation.ConclusionsIndirect 1H-MR imaging method is able to measure H217O concentration by using R2 values and conventional 3-T MR equipment. Normalised R2 relative dynamic changes after the intravenous injection of a H217O saline solution provide a unique opportunity to map water pathophysiology in vivo, opening the analysis of aquaporins status and modifications by disease at clinically available 3-T proton MR scanners.

【 授权许可】

CC BY