T1 relaxation times for viability evaluation of the engrafted and the native liver in a rat model of heterotopic auxiliary liver transplantation: a pilot study

✍ Scribed by Ye-Dong Fan; Bart Vanzieleghem; Eric Achten; Yves De Deene; Luc Defreyne; Marleen Praet; Jacques Van Huysse; Marc Kunnen; Bernard de Hemptinne

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 488 KB
• Volume: 14
• Category: Article
• ISSN: 0952-3480
• DOI: 10.1002/nbm.719

✦ Synopsis

Following a heterotopic auxiliary liver transplantation, commonly used measurements are either invasive or non-indicative of individual viability of the coexisting engrafted and native livers. Magnetic resonance imaging (MRI) was therefore tested for its potential to monitor the post-transplant hepatic viability in a rat model. Thirteen Wistar rats were systematically evaluated with MRI and serum biochemical liver parameters. Post-transplant complications and the causes of animal death were identified by autopsy and histo-pathological examinations. The data of the healthy survivors were compared with those of the rats that developed complications. On MRI, the hepatic complications could be depicted in the individual livers. A specific pattern of signal evolution was found in the livers of the healthy survivors: the mean T 1 relaxation times of the engrafted livers increased immediately after transplantation (476 AE 64 ms, mean AE standard deviation, pre-operative; 730 AE 48 ms, week 1) and then declined steadily to a 3 month value of 489 AE 246 ms, while, following a transient first rise (476 AE 64 ms, pre-operative; 589 AE 28 ms, week 1), the mean T 1 value of the native livers increased again 4 weeks after surgery and reached a 3 month value of 859 AE 43 ms. However, in the rats with various complications, the mean T 1 relaxation times of the engrafted livers continued to increase throughout the first post-operative month (760 AE 48 ms, week 1; 922 AE 76 ms, week 4), while that of the native liver only varied mildly (546 AE 25 ms, week 1; 473 AE 25 ms, week 4). After the first post-transplant week, the healthy engrafted livers could already be distinguished from those with complications by a significant decrease in T 1 relaxation times. These data suggest that, besides demonstrating major complications, MRI may allow one to monitor the viability of each liver by analysing the relative signal intensity and T 1 relaxation times after a heterotopic auxiliary liver transplantation.