Effect of arterial deprivation on growing femoral epiphysis: quantitative magnetic resonance imaging using a piglet model

• Published in: Korean journal of radiology 2015, 16(3), , pp.617-625
• Main Authors: Cheon, Jung-Eun, Yoo, Won Joon, Kim, In-One, Kim, Woo Sun, Choi, Young Hun
• Format: Article
• Language: English
• Subjects: Animals; Arteries - physiopathology; Bone marrow; Diffusion Magnetic Resonance Imaging - methods; Disease Models, Animal; Embolism - complications; Embolization; Epiphyses - blood supply; Epiphyses - pathology; Femur Head - blood supply; Femur Head - pathology; Ischemia; Magnetic resonance imaging; Male; Medical imaging; Osteonecrosis - pathology; Pediatric Imaging; Pelvic Bones - blood supply; Pelvic Bones - pathology; Pharmacokinetics; Reperfusion Injury - complications; Reperfusion Injury - diagnosis; Swine; Veins & arteries; 방사선과학
• ISSN: 1229-6929; 2005-8330
• DOI: 10.3348/kjr.2015.16.3.617

To investigate the usefulness of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion MRI for the evaluation of femoral head ischemia. Unilateral femoral head ischemia was induced by selective embolization of the medial circumflex femoral artery in 10 piglets. All MRIs were performed immediately (1 hour) and after embolization (1, 2, and 4 weeks). Apparent diffusion coefficients (ADCs) were calculated for the femoral head. The estimated pharmacokinetic parameters (Kep and Ve from two-compartment model) and semi-quantitative parameters including peak enhancement, time-to-peak (TTP), and contrast washout were evaluated. The epiphyseal ADC values of the ischemic hip decreased immediately (1 hour) after embolization. However, they increased rapidly at 1 week after embolization and remained elevated until 4 weeks after embolization. Perfusion MRI of ischemic hips showed decreased epiphyseal perfusion with decreased Kep immediately after embolization. Signal intensity-time curves showed delayed TTP with limited contrast washout immediately post-embolization. At 1-2 weeks after embolization, spontaneous reperfusion was observed in ischemic epiphyses. The change of ADC (p = 0.043) and Kep (p = 0.043) were significantly different between immediate (1 hour) after embolization and 1 week post-embolization. Diffusion MRI and pharmacokinetic model obtained from the DCE-MRI are useful in depicting early changes of perfusion and tissue damage using the model of femoral head ischemia in skeletally immature piglets.