OBJECT: To determine whether superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging could demonstrate signal recovery delay in irradiated areas of rat livers. We also investigated the relationship between MR imaging and histological findings. MATERIALS AND METHODS: Twelve rats received 20 μmol iron/kg of SPIO followed by X-irradiation to the right upper abdomen 4 h later. Radiation doses were 0, 50 and 70 Gy. Hepatic signals were assessed on unenhanced T 2 (*) -weighted images for up to 7 days using a 9.4-Tesla scanner. The livers were excised on day 7 and examined histologically. RESULTS: Normalized relative signal intensity of 70 Gy-irradiated right liver lobe (2.36 ± 0.22) and 50 Gy-irradiated right liver lobe (2.37 ± 0.46) was significantly lower than that of the non-irradiated right liver lobe (4.04 ± 0.28) on day 7, respectively (p < 0.05). Pearson product-moment correlation coefficient between relative intensity of the liver and the number of hepatic iron deposits was -0.588 (p < 0.01). CONCLUSION: Superparamagnetic iron oxide-enhanced MR imaging could demonstrate signal recovery delay in irradiated areas of rat livers. It seems that the signal recovery delay in irradiated areas was due to SPIO-derived iron deposition. Hepatic signal recovery could be a novel diagnostic marker for delineation of irradiated areas.
OBJECT: To determine whether superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging could demonstrate signal recovery delay in irradiated areas of rat livers. We also investigated the relationship between MR imaging and histological findings. MATERIALS AND METHODS: Twelve rats received 20 μmol iron/kg of SPIO followed by X-irradiation to the right upper abdomen 4 h later. Radiation doses were 0, 50 and 70 Gy. Hepatic signals were assessed on unenhanced T 2 (*) -weighted images for up to 7 days using a 9.4-Tesla scanner. The livers were excised on day 7 and examined histologically. RESULTS: Normalized relative signal intensity of 70 Gy-irradiated right liver lobe (2.36 ± 0.22) and 50 Gy-irradiated right liver lobe (2.37 ± 0.46) was significantly lower than that of the non-irradiated right liver lobe (4.04 ± 0.28) on day 7, respectively (p < 0.05). Pearson product-moment correlation coefficient between relative intensity of the liver and the number of hepatic iron deposits was -0.588 (p < 0.01). CONCLUSION: Superparamagnetic iron oxide-enhanced MR imaging could demonstrate signal recovery delay in irradiated areas of rat livers. It seems that the signal recovery delay in irradiated areas was due to SPIO-derived iron deposition. Hepatic signal recovery could be a novel diagnostic marker for delineation of irradiated areas.
Authors: T Masui; H Yan; I Kosugi; S Sakamoto; T Nishimura; M Takahashi; M Kaneko; B Fritz-Zieroth Journal: Acta Radiol Date: 1996-09 Impact factor: 1.990
Authors: Karen C Briley-Saebo; Lars O Johansson; Svein Olaf Hustvedt; Anita G Haldorsen; Atle Bjørnerud; Zahi A Fayad; Haakan K Ahlstrom Journal: Invest Radiol Date: 2006-07 Impact factor: 6.016
Authors: R Lawaczeck; H Bauer; T Frenzel; M Hasegawa; Y Ito; K Kito; N Miwa; H Tsutsui; H Vogler; H J Weinmann Journal: Acta Radiol Date: 1997-07 Impact factor: 1.990
Authors: B Hamm; T Staks; M Taupitz; R Maibauer; A Speidel; A Huppertz; T Frenzel; R Lawaczeck; K J Wolf; L Lange Journal: J Magn Reson Imaging Date: 1994 Sep-Oct Impact factor: 4.813