MRI visualization of rodent liver structure and peritoneal adhesion with dialyzate enhancement.

This study investigated the use of peritoneal dialysis fluid (dialyzate) as a MR contrast agent to visualize the liver structure and peritoneal adhesion in rats at 7 T. Intraperitoneal injection of dialyzate (approximately 0.1 ml/g) yielded excellent and consistent intraperitoneal enhancement that delineated the liver lobular structure in all rats studied (N = 8). It also allowed the MR detection of peritoneal adhesions that were surgically induced. MR measurements of adhesion surface areas correlated well with the postmortem estimations (R = 0.99; N = 6). Dialyzate persisted in the intraperitoneal cavity for up to 2 days. T(1) and T(2) values of undiluted dialyzate were found to be 3017.5 +/- 35.3 ms and 108.4 +/- 2.0 ms, respectively. These findings demonstrated dialyzate-enhanced MRI as a potentially valuable technique to localize certain activities within liver (such as local tumor metastasis), and to monitor therapeutic interventions (e.g., against peritoneal adhesion) in preclinical research using small animal models.