title: Intravoxel incoherent motion (IVIM) analysis of vertebral bone marrow changes after radiation exposure from diagnostic imaging and interventional procedures.
abstract: Background High cumulative radiation dose in cancer patients warrants systemic examination of possible changes in bone marrow. Purpose To assess retrospectively changes in vertebral bone marrow diffusion and perfusion using intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in hepatocellular carcinoma (HCC) patients after exposure to radiation from diagnostic imaging and interventional procedures. Material and Methods A total of 21 IVIM-DWI sets in 20 HCC patients, consisting of baseline and follow-up liver magnetic resonance imaging (MRI) with an interval less than 100 days, were reviewed after varying levels of radiation exposure from transarterial chemoembolization (TACE), multiphase liver CT, and abdominal radiography. IVIM parameters (apparent diffusion coefficient [ADC], true diffusion coefficient [D], pseudodiffusion coefficient [D*], and perfusion fraction [PF]) of vertebral bone marrow were analyzed for significant differences between baseline and follow-up MRI using Wilcoxon signed-rank test, and for correlations with cumulative effective dose, as well as time interval between last radiation exposure and follow-up MRI using Spearman's correlation. Results Compared to baseline MRI, ADC, D*, and PF significantly decreased on follow-up MRI (ADC: median [interquartile range], 0.405 × 103mm2/s [0.364-0.477] versus 0.390 [0.348-0.461]; D*: 24.011 [18.141-29.584] versus 20.815 [15.022-28.347]; PF: 10.960% [8.828-12.985] versus 9.125 [8.606-12.803]) ( P < 0.05). There was no significant difference in D ( P = 0.807). Cumulative effective dose was moderately correlated with decrease in D* (r = 0.434). In addition, longer intervals between last exposure and follow-up MRI showed negative correlations with changes in D and ADC (r = -0.352 and -0.333, respectively). Conclusion Vertebral bone marrow diffusion and perfusion parameters were significantly changed after exposure to medical radiation.
authors.affiliation: 1 Department of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Min A
authors.initials: MA
authors.lastname: Yoon
authors.affiliation: 1 Department of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Suk-Joo
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: 1 Department of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chang Hee
authors.initials: CH
authors.lastname: Lee
authors.affiliation: 2 Department of Radiology, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chang Ho
authors.initials: CH
authors.lastname: Kang
authors.affiliation: 2 Department of Radiology, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyung-Sik
authors.initials: KS
authors.lastname: Ahn
authors.affiliation: 3 Department of Radiology, Korea University Ansan Hospital, Korea University College of Medicine, Gyeonggi-do, Republic of Korea.
authors.forename: Baek Hyun
authors.initials: BH
authors.lastname: Kim
mesh_terms: D001853:Bone Marrow / Q000000981:diagnostic imaging*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009038:Motion; D011829:Radiation Dosage; D000069079:Radiation Exposure; D012189:Retrospective Studies; D013131:Spine / Q000000981:diagnostic imaging*
keywords: Intravoxel incoherent motion (IVIM); bone marrow; radiation