Validity and Feasibility of Transient Elastography for the Transplanted Liver in the Peritransplantation Period

Background. Transient elastography has recently been suggested to be capable of detecting dynamic changes in stiffness that accompanies acute liver damage. Its feasibility and usefulness in the perioperative period in living donor liver transplantation (LDLT) have not been studied. Methods. We evaluated 678 liver stiffness measurements (LSMs) obtained in the peritransplantation period from 24 LDLT recipients, 24 corresponding donors (preoperatively only), another five donors with a remnant right liver, and three deceased donor liver transplantation recipients. The LSM was performed once preoperatively, every morning postoperatively until postoperative day 14, and three times a week after that until the patient was discharged from the hospital. Results. Overall LSM success rate (valid shots/total shots) was 0.929±0.119. There was a significant negative relationship between the LSM success rate and thoracic belt thickness (P<0.0021). The interquartile range to median value rate of LSMs remained high (21.1%±11.2%) compared with the preoperative values (15.6%±8.5%), even 1 month after the transplantation. Among LDLT recipients (n=24), the LSM value was highest in the first postoperative week and declined thereafter. Recipients with complications had significantly higher LSM values than those without complications in the fourth postoperative week (POW4; P=0.0066) and POW5 or later (P=0.0028). All cases of acute cellular rejection had a concomitant sharp rise in liver stiffness and a rapidly depleted portal flow. Conclusions. Despite the high variability of the results, transient elastography may be an efficient method for monitoring changes in dynamic liver stiffness in the early posttransplant period.