PURPOSE: To examine the use of O-methoxy poly(ethylene)glycol-O'-succinyl-N-epsilon-poly(L-lysyl) gadolinium diethylenetriaminepentaacetic acid (MPEG-PL-Gd-DTPA) as a potential magnetic resonance (MR) angiographic contrast agent for the detection of gastrointestinal (GI) bleeding. MATERIALS AND METHODS: MPEG-PL-Gd-DTPA was used for blood pool enhancement, and MPEG-PL-technetium-99m DTPA was used for planar nuclear imaging studies. GI bleeding was tested in rats by controlled injection of contrast material-doped blood through a jejunostomy catheter. MR imaging was performed at 1.5 T. RESULTS: Ideal flip angle, used with a spoiled gradient-echo pulse sequence, was 40 degrees. The smallest amount of hemorrhage detected at MR imaging was 0.05 mL; at nuclear imaging it was 0.02 mL. With the superior spatial resolution of MR imaging, individual loops of contrast material-filled bowel were identified and bleeding points were pinpointed. CONCLUSION: GI hemorrhage can be easily detected at MR imaging if a long circulating macromolecular contrast agent is used to decrease the T1 of extravasated blood.
PURPOSE: To examine the use of O-methoxy poly(ethylene)glycol-O'-succinyl-N-epsilon-poly(L-lysyl) gadolinium diethylenetriaminepentaacetic acid (MPEG-PL-Gd-DTPA) as a potential magnetic resonance (MR) angiographic contrast agent for the detection of gastrointestinal (GI) bleeding. MATERIALS AND METHODS:MPEG-PL-Gd-DTPA was used for blood pool enhancement, and MPEG-PL-technetium-99m DTPA was used for planar nuclear imaging studies. GI bleeding was tested in rats by controlled injection of contrast material-doped blood through a jejunostomy catheter. MR imaging was performed at 1.5 T. RESULTS: Ideal flip angle, used with a spoiled gradient-echo pulse sequence, was 40 degrees. The smallest amount of hemorrhage detected at MR imaging was 0.05 mL; at nuclear imaging it was 0.02 mL. With the superior spatial resolution of MR imaging, individual loops of contrast material-filled bowel were identified and bleeding points were pinpointed. CONCLUSION:GI hemorrhage can be easily detected at MR imaging if a long circulating macromolecular contrast agent is used to decrease the T1 of extravasated blood.
Authors: Elaine Y Yu; Prashant Chandrasekharan; Ran Berzon; Zhi Wei Tay; Xinyi Y Zhou; Amit P Khandhar; R Matthew Ferguson; Scott J Kemp; Bo Zheng; Patrick W Goodwill; Michael F Wendland; Kannan M Krishnan; Spencer Behr; Jonathan Carter; Steven M Conolly Journal: ACS Nano Date: 2017-11-30 Impact factor: 15.881
Authors: Mei Tian; Xiaoxia Wen; Edward F Jackson; Chaan Ng; Rajesh Uthamanthil; Dong Liang; Juri G Gelovani; Chun Li Journal: Contrast Media Mol Imaging Date: 2011-01-06 Impact factor: 3.161