HTK-N as a new preservation solution for human kidney preservation: Results of a pilot randomized controlled clinical phase II trial in living donor transplantation.

BACKGROUND: HTK-N was developed based on the traditional HTK preservation solution, resulting in stronger protection against reactive oxygen species as well as better tolerance to hypothermia and ischemia. Aim of the present study was to compare HTK-N to HTK in clinical kidney transplantation demonstrating safety and non-inferiority. METHODS: We performed a randomized controlled single blinded clinical phase II trial in patients undergoing living donor kidney transplantation. After retroperitoneoscopic nephrectomy kidneys were either perfused and stored with classical HTK solution or the new HTK-N solution. Primary endpoint was the glomerular filtration rate (eGFR according to CKD EPI) 3 months after transplantation. Secondary endpoints included graft and patient survival beside others. RESULTS: The study included 42 patients, of which 22 were randomized in the HTK-N group and 20 in the HTK group. The primary end point showed a mean eGFR of 55.4 ± 14.0 ml/min/1.73 m2 in the HTK group compared to a GFR of 57.2 ± 16.7 ml/min/m2 in the HTK-N group (P = .72). Regarding secondary endpoints, there were no apparent differences. Posttransplant graft and patient survival was 100%. CONCLUSION: This study is the first clinical application of HTK-N for kidney preservation and demonstrates non-inferiority compared to HTK in the setting of living donor kidney transplantation.

Therapy of pyogenic liver abscess with a primarily unknown cause.

PURPOSE: Pyogenic liver abscess (PLA) is a collection of pus in the liver, often without a known direct cause. There is discord on the best diagnostic and therapeutic strategy. We aimed to examine these questions in our patient cohort. METHODS: A total of 66 out of 309 patients with PLA at our tertiary referral center between 2012 and 2020 had a primarily unknown cause. We analyzed PLA configuration, comorbidities, and whether an underlying cause could be found later. Therapy was sorted by antibiotics alone, percutaneous drainage, and primary surgery. Success was assessed by a change of initial therapy, in-hospital mortality, and mean hospital stay. RESULTS: Overall mortality was 18%; in 55%, a causative condition could be found. CRP, GGT, size, and multiple localization go along with higher mortality. Antibiotics alone had a failure rate of 82%. Percutaneous drainage was successful in 70% of cases. Surgery was mainly reserved for failed previous non-surgical treatment and had in-hospital mortality of 12%. CONCLUSIONS: PLA goes along with high mortality. In the majority of all patients, a causative condition can be identified by detailed diagnostics. Percutaneous drainage together with antibiotics is the therapy of choice and is successful in 70% of cases. If drainage is insufficient or impossible, surgery is an effective alternative.

Liver maximum capacity (LiMAx) test as a helpful prognostic tool in acute liver failure with sepsis: a case report.

BACKGROUND: Acute liver failure (ALF) is a life-threatening entity particularly when infectious complications worsen the clinical course. Urgent liver transplantation (LT) is frequently the only curative treatment. However, in some cases, recovery is observed under conservative treatment. Therefore, prognostic tools for estimating course of the disease are of great clinical interest. Since laboratory parameters sometimes lack sensitivity and specificity, enzymatic liver function measured by liver maximum capacity (LiMAx) test may offer novel and valuable additional information in this setting. CASE PRESENTATION: We here report the case of a formerly healthy 20-year old male caucasian patient who was admitted to our clinic for ALF of unknown origin in December 2017. Laboratory parameters confirmed the diagnosis with an initial MELD score of 28 points. Likewise, enzymatic liver function was significantly impaired with a value of 147 [> 315] µg/h/kg. Clinical and biochemical analyses for viral-, autoimmune-, or drug-induced hepatitis were negative. Liver synthesis parameters further deteriorated reaching a MELD score of 40 points whilst clinical course was complicated by septic pneumonia leading to severe hepatic encephalopathy grade III-IV, finally resulting in mechanical ventilation of the patient. Interestingly, although clinical course and laboratory data suggested poor outcome, serial LiMAx test revealed improvement of the enzymatic liver function at this time point increasing to 169 µg/h/kg. Clinical condition and laboratory data slowly improved likewise, however with significant time delay of 11 days. Finally, the patient could be dismissed from our clinic after 37 days. CONCLUSION: Estimating prognosis in patients with ALF is challenging by use of the established scores. In our case, improvement of enzymatic liver function measured by the LiMAx test was the first parameter predicting beneficial outcome in a patient with ALF complicated by sepsis.

Reconditioning by end-ischemic hypothermic in-house machine perfusion: A promising strategy to improve outcome in expanded criteria donors kidney transplantation.

This clinical study evaluates end-ischemic hypothermic machine perfusion (eHMP) in expanded criteria donors (ECD) kidneys. eHMP was initiated upon arrival of the kidney in our center and continued until transplantation. Between 11/2011 and 8/2014 eHMP was performed in 66 ECD kidneys for 369 (98-912) minutes after 863 (364-1567) minutes of cold storage (CS). In 49 of 66 cases, the contralateral kidney from the same donor was preserved by static CS only and accepted by another Eurotransplant (ET) center. Five (10.2%) of these kidneys were ultimately judged as "not transplantable" by the accepting center and discarded. After exclusion of early unrelated graft losses, 43 kidney pairs from the same donor were eligible for direct comparison of eHMP vs CS only: primary non-function and delayed graft function (DGF) were 0% vs 9.3% (P=.04) and 11.6% vs 20.9% (P=.24). There was no statistically significant difference in 1-year graft survival (eHMP vs CS only: 97.7% vs 88.4%, P=.089). In a multivariate analysis, eHMP was an independent factor for prevention of DGF (OR: 0.28, P=.041). Development of DGF was the strongest risk factor for 1-year graft failure (Renal resistance: 38.2, P<.001). In summary, eHMP is a promising reconditioning technique to improve the quality and acceptance rate of suboptimal grafts.

Career intentions of female surgeons in German liver transplant centers considering family and lifestyle priorities.

PURPOSE: Women represent up to 60 % of students entering the medical profession in many countries in the world. However, the proportion of women to men is not accordingly balanced among surgical residents and especially in leadership positions in surgery. Therefore, we investigated the career goals as well as family and lifestyle priorities of female surgeons in German liver transplant centers. METHODS: A standardized questionnaire was developed using the web-based survey tool SurveyMonkey®. Questionnaires were distributed electronically to 180 female surgeons in 24 German liver transplant centers. A total of 81 completed questionnaires were analyzed. RESULTS: Female surgeons in German liver transplant centers are eager to assume leadership positions and do not wish to follow traditional role models. After finishing training, most female surgeons plan to continue working at a university hospital. About 80 % of the respondents intend to continue working full time and wish to combine career and family. CONCLUSIONS: This is the first survey on career intentions of female surgeons in Germany. In the face of gender changes in the medical profession, we were able to demonstrate that female surgeons are willing to fill leadership positions. Individual and institutional creative modifications are necessary if the advancement of women in surgery is to be promoted.

Liver transplantation in infants with biliary atresia: comparison of primary versus temporary abdominal closure.

INTRODUCTION: Biliary atresia (BA) is the most frequent disease leading to liver transplantation (LT) in infants. Since the patients often require transplantation before reaching a body weight of 10 kg, it is necessary to perform living-related or split liver transplantation by using a left lateral segment. However, this graft often exceeds a graft body weight ratio (GBWR) of 4. Because of the size mismatch and poor portal venous blood flow in most recipients, temporary abdominal closure is often favoured. The aim of the present study is to investigate the feasibility of primary abdominal closure in this group of extremely small infants undergoing LT. PATIENTS AND METHODS: All patients with the diagnosis of BA and a body weight ≤10 kg who underwent LT in our centre between January 2004 and December 2014 were included in this study. Patients who received primary abdominal closure at transplantation (group 1) were compared with those receiving temporary abdominal closure (group 2). The postoperative clinical and biochemical course was analysed. The outcome was determined and correlated with body and graft weight and the GBWR. RESULTS: Sixty-six LTs were performed in 57 patients in the study period (22 male, 35 female). Thirty-six patients received primary closure (group 1). Twenty-eight patients received temporary closure (group 2). Mean age at LT was 10 months (range 3-26) and mean GBWR 4.8 (range 2.9-9.3). A GBWR ≥4 occurred in 61.1 % in group 1 and in 60.9 % in group 2. There was no significant difference between both groups concerning body weight, graft weight or GBWR. Vascular thrombosis occurred in 8 patients (22 %) and 15 patients (42 %) in group 1 and in 10 patients (36 %) and 11 patients (39 %) in group 2, respectively. Six patients (17 %) of group 1 and five patients (18 %) of group 2 developed an intraabdominal infection postoperatively. After a mean follow-up of 4.6 years (range 1 month-11.1 years), patient and graft survival were 90.1 and 75 % in group 1 and 78.3 and 64.3 % in group 2, respectively. CONCLUSION: In our study, primary abdominal closure displays a similar outcome in comparison to temporary abdominal closure.

Two and a Half Hours of Cardiopulmonary Resuscitation in a Deceased Brain Dead Donor before Liver Transplantation - A Good Idea to Accept?

The sequelae of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) in organ donors potentially results in ischemic organ injury and graft dysfunction after transplantation. Thresholds of resuscitation times in brain dead liver donors have not been established so far. We report the case of a brain dead liver donor who experienced 2.5 hours of CPR whose liver was successfully transplanted. A 75-year-old male experienced CA and was treated by CPR with streptokinase application for 2.5 hours until stabilization of cardiac function. Brain death was diagnosed at the day of admission and organ donation carried out within 24 hours. The DRI was 2.2 with a CIT of 8.8 hours. The liver was transplanted into a 64-year-old recipient suffering from alcoholic liver cirrhosis and a MELD-score of 10 non representative for severity of disease. During follow up of 4 years ERCP and stenting was performed regularly for biliary anastomosis stenosis. The patient remained in a very good overall state of health without any signs of liver dysfunction. This case demonstrates that an extensive period of CPR is not an obligatory exclusion criterion for liver donation. Thresholds of CPR times as well as predictive factors in donors with CA should be established.

Training, work, and lifestyle of transplant physicians and surgeons in Germany.

BACKGROUND: International data on training, work, and lifestyle of transplant physicians and surgeons are scarce. Such data might help in development of uniform education paths and provide insights for young clinicians interested in this field. This study aimed at the evaluation of these data in all transplant-associated medical disciplines. METHODS: A survey on professional and academic training, workload, and lifestyle was generated. The questionnaire was distributed to all members of the German Transplant Association (DTG), utilizing the tool SurveyMonkey(®) . RESULTS: A total of 127 members of the DTG responded (male/female 66.1%/33.9%, 45.8±10.3 years). The majority had been working in transplant medicine for more than 10 years (61.9%). Fifteen respondents (11.8%) obtained an official European certification (European Union of Medical Specialists). A total of 57 (48.3%) respondents worked full time on research during training. The research focus was clinical for most respondents (n=72, 61.5%). An average working time of 62±1.5 h/wk was reported. Fifty-eight percent of all respondents complained of inadequate remuneration and 50% reported inadequate acknowledgment of their professional performance. CONCLUSION: This is the first study reporting characteristics of training, work, and lifestyle in an interdisciplinary cohort of German transplant physicians and surgeons. Enormous efforts in clinical and research work were reported, associated with high rates of professional and financial dissatisfaction.

Single-Center Experience on Liver Transplantation for Model for End-Stage Liver Disease Score 40 Patients.

BACKGROUND: Organ shortage and waiting list mortality have led to changes in the allocation policy in Eurotransplant. AIM: To identify factors influencing the survival of liver transplanted patients with model for end-stage liver disease (MELD) score of 40. PATIENTS AND METHODS: Data of listed adult patients who reached a MELD score 40 in the period 12/2006-06/2010 were reviewed. Donor/graft and recipient characteristics, and operative details were analyzed. Statistical analysis encompassed Kaplan-Meier analysis/log-rank test as well as univariate and multivariable regression analyses. RESULTS: Forty-eight patients achieved a MELD score 40. Thirty patients were transplanted, whereas 18 patients were not. Three-month, 1-year, and 5-year patient and graft survival for transplanted patients was 53, 50, and 47 %, respectively. Three-month and 1-year survival after listing was 11 and 6 % for not transplanted patients, respectively (p < 0.0001). Multivariable analysis revealed pre-operative dialysis (p = 0.0246) and portal vein thrombosis (PVT) (p = 0.0231) to be independent prognostic factors for post-transplant patient survival. A point scoring system was created, which reached statistical significance (p = 0.0007). One-year and 5-year survival for scores 0, 1, and 2 were 72 and 64, 42 and 42 and 0 %, respectively. There was no statistical difference in transplantation costs between patients who survived or died (p = 0.1578). CONCLUSIONS: At our center, coexistence of pre-operative dialysis and PVT represents a clear contraindication for LT regarding MELD score 40 patients.

Safely expanding the donor pool: brain dead donors with history of temporary cardiac arrest.

BACKGROUND & AIMS: Cardiac arrest (CA) in deceased organ donors can potentially be associated with ischaemic organ injury, resulting in allograft dysfunction after liver transplantation (LT). The aim of this study was to analyse the influence of cardiac arrest in liver donors. METHODS: We evaluated 884 consecutive adult patients undergoing LT at our Institution from September 2003 to December 2011. Uni- and multivariable analyses was performed to identify predictive factors of outcome and survival for organs from donors with (CA donor) and without (no CA donor) a history of cardiac arrest. RESULTS: We identified 77 (8.7%) CA donors. Median resuscitation time was 16.5 (1-150) minutes. Allografts from CA donors had prolonged CIT (p = 0.016), were obtained from younger individuals (p < 0.001), and had higher terminal preprocurement AST and ALT (p < 0.001) than those of no CA donors. 3-month, 1-year and 5-year survival for recipients of CA donor grafts was 79%, 76% and 57% and 72.1%, 65.1% and 53% for no CA donor grafts (log rank p = 0.435). Peak AST after LT was significantly lower in CA donor organs than in no CA donor ones (886U/l vs 1321U/l; p = 0.031). Multivariable analysis identified CIT as a risk factor for both patient and graft survival in CA donors. CONCLUSION: This analysis represents the largest cohort of liver donors with a history of cardiac arrest. Reasonable selection of these donors constitutes a safe approach to the expansion of the donor pool. Rapid allocation and implantation with diminution of CIT may further improve the outcomes of livers from CA donors.

Donor information based prediction of early allograft dysfunction and outcome in liver transplantation.

BACKGROUND & AIMS: Poor initial graft function was recently newly defined as early allograft dysfunction (EAD) [Olthoff KM, Kulik L, Samstein B, et al. Validation of a current definition of early allograft dysfunction in liver transplant recipients and analysis of risk factors. Liver Transpl 2010; 16: 943]. Aim of this analysis was to evaluate predictive donor information for development of EAD. METHODS: Six hundred and seventy-eight consecutive adult patients (mean age 51.6 years; 60.3% men) who received a primary liver transplantation (LT) (09/2003-12/2011) were included. Standard donor data were correlated with EAD and outcome by univariable/multivariable logistic regression and Cox proportional hazards to identify prognostic donor factors after adjustment for recipient confounders. Estimates of relevant factors were utilized for construction of a new continuous risk index to develop EAD. RESULTS: 38.7% patients developed EAD. 30-day survival of grafts with and without EAD was 59.8% and 89.7% (P < 0.0001). 30-day survival of patients with and without EAD was 68.5% and 93.1% (P < 0.0001) respectively. Donor body mass index (P = 0.0112), gGT (P = 0.0471), macrosteatosis (P = 0.0006) and cold ischaemia time (CIT) (P = 0.0031) were predictors of EAD. Internal cross validation showed a high predictive value (c-index = 0.622). CONCLUSIONS: Early allograft dysfunction correlates with early results of LT and can be predicted by donor data only. The newly introduced risk index potentially optimizes individual decisions to accept/decline high risk organs. Outcome of these organs might be improved by shortening CIT.

Using pediatric liver grafts (≤ 6 yr) for adult recipients: A considerable option?

In LT, the common policy is to allocate pediatric liver grafts to pediatric recipients. Pediatric organs are also offered to adults if there is no pediatric recipient. However, they are rarely accepted for adult recipients. So far, there is no information available reporting outcome of LT in adult recipients using pediatric livers from donors ≤ 6 yr. In this study, we included nine adult recipients (seven females and two males) who received grafts from children ≤ 6 yr from January 2008 to December 2013. We evaluated the graft quality, the GBWR and analyzed the recipients' perioperative course. Laboratory samples and graft perfusion were analyzed. Nine adults with a median age of 49 yr (range: 25-65) and a median weight of 60 kg (range: 48-64) underwent LT with a pediatric donor graft. Median donor age was five yr (range: 3-6). Median GBWR was 1.02 (range: 0.86-1.45). After a median follow-up of 3.9 yr (range: 11 months-6.6 yr), patient survival was 100%; graft survival was 89%. One patient needed re-transplantation on the second postoperative day due to PNF. Eight recipients were discharged from the ICU after 2-9 days with a regular graft function. Doppler scans revealed regular flow patterns at any time. Only if denied for pediatric recipients, the use of pediatric livers from donors ≤ 6 yr for adult recipients is a considerable option.

Liver transplantation for acute liver failure: are there thresholds not to be crossed?

Factors predicting survival after liver transplantation (LT) for irreversible acute liver failure (ALF) are rare. The aim of this study was to identify prognostic preoperative factors of patients with ALF that predict mortality after LT to avoid futile transplantation. From chart review, we identified 57 patients receiving transplants for ALF from 12/2000 to 09/2010. Recipient and donor data were analyzed and correlated with in-hospital mortality and patient survival by univariable/multivariable logistic regression and Cox proportional hazards. The survival rates at 30 days and 12 months were 77.2% and 64.9%, respectively. The in-hospital mortality rate was 29.8%. Follow-up of patients discharged from the hospital alive showed 30-day and 12-month survivals of 100% and 92.5%, respectively. Multivariable analysis of factors known preoperatively showed that the lowest pH of the recipient before LT (P = 0.03) was independently associated with in-hospital mortality, and the recipient's BMI (P = 0.03) and the lowest pH before LT (P = 0.03) were independently associated with patient survival. A pH of 7.26 was the calculated cutoff (ROC) for increased in-hospital mortality. Donor factors did not affect patient survival. Patients with ALF and a pH ≤ 7.26 have the worst outcome after liver transplantation. Therefore, emergency liver transplantation should be critically discussed for each individual.

MELD at POD 1 as a predictor of outcome in liver allografts with peak AST >5000 U/l.

Perioperative liver graft injury is associated with elevation of aminotransferases after orthotopic liver transplantation (OLT). Values above 5000 U/l usually are regarded as extreme liver graft injury (ELGI). Some patients and organs recover from this critical condition. The aim of the study was to evaluate factors contributing to graft and patient survival after ELGI. From chart review we identified 64 of 917 OLT adult patients (median age 54.2 years; 68.8% males) transplanted between 11/2003 and 02/2012, who presented ELGI after OLT. Donor and recipient factors were analyzed and correlated with the outcome by univariable and multivariable methods. Multivariable cox proportional hazards showed that recipient's BMI (P = 0.01), model for end stage liver disease (MELD) score before OLT (P = 0.02) and laboratory MELD score 24 h after OLT (P = 0.01) were independently associated with patient survival. 30-days and 12-months survival in patients with a postoperative laboratory MELD higher than 31 was 21.4%, while patients with a postoperative laboratory MELD lower than 31 displayed 30-days and 12-months survival rates of 80% and 71.8%, respectively (P < 0.001). Retransplantation in the setting of ELGI after OLT should be based on all available data. Utilization of the postoperative labMELD enables the transplant physician within 24 h after transplantation to identify necessity of retransplantation objectively.

Subnormothermic machine perfusion for preservation of porcine kidneys in a donation after circulatory death model.

Machine perfusion for preservation led to compelling success for the outcome of renal transplantation. Further refinements of methods to decrease preservation injury remain an issue of high interest. This study investigates functional and morphological aspects of kidneys preserved by subnormothermic (20 °C) machine perfusion (SNTM) compared with oxygenated hypothermic machine perfusion (HMPox) and cold storage (CS) in a donation after circulatory death (DCD) model. After 30 min of warm ischaemia, porcine kidneys were randomly assigned to preservation for 7 h by CS, HMPox or SNTM. Afterwards, kidneys were reperfused for 2 h with autologous blood in vitro for assessment of function and integrity. Application of SNTM for preservation led to significantly higher blood flow and urine output compared with both other groups. SNTM led to a twofold increased creatinine clearance compared with HMPox and 10-fold increased creatinine clearance compared with CS. Structural integrity was best preserved by SNTM. In conclusion, this is the first study on SNTM for kidneys from DCD donors. SNTM seems to be a promising preservation method with the potential to improve functional parameters of kidneys during reperfusion.

AI-based digital histopathology for perihilar cholangiocarcinoma: A step, not a jump.

Introduction: Perihilar cholangiocarcinoma (PHCC) is a rare malignancy with limited survival prediction accuracy. Artificial intelligence (AI) and digital pathology advancements have shown promise in predicting outcomes in cancer. We aimed to improve prognosis prediction for PHCC by combining AI-based histopathological slide analysis with clinical factors. Methods: We retrospectively analyzed 317 surgically treated PHCC patients (January 2009-December 2018) at the University Hospital of Essen. Clinical data, surgical details, pathology, and outcomes were collected. Convolutional neural networks (CNN) analyzed whole-slide images. Survival models incorporated clinical and histological features. Results: Among 142 eligible patients, independent survival predictors were tumor grade (G), tumor size (T), and intraoperative transfusion requirement. The CNN-based model combining clinical and histopathological features demonstrates proof of concept in prognosis prediction, limited by histopathological complexity and feature extraction challenges. However, the CNN-based model generated heatmaps assisting pathologists in identifying areas of interest. Conclusion: AI-based digital pathology showed potential in PHCC prognosis prediction, though refinement is necessary for clinical relevance. Future research should focus on enhancing AI models and exploring novel approaches to improve PHCC patient prognosis prediction.

Transplantation for Primary Sclerosing Cholangitis: Outcomes and Recurrence.

Primary sclerosing cholangitis (PSC) is characterized by inflammation of the whole bile duct system. Liver transplantation is only approved as a curative treatment when it comes to end-stage liver disease. The aim of our study was to assess morbidity, survival rates and PSC recurrence and the impact of donor characteristics in long-term follow-up. This was an IRB-approved retrospective study. A total of 82 patients were identified who were transplanted between January 2010 and December 2021 for PSC. Among these patients, 76 adult liver transplant PSC patients and their corresponding donors were analyzed. Three pediatric cases and three adult patients with a follow-up within <1 year were excluded from further analysis. Median (range) age was 47 years (18-70) with a median (range) lab-MELD of 16 (7-40). Median (range) ICU and hospital stays were 4.6 days (0-147) and 21 days (1-176), respectively. The majority of patients suffered from Crohn's disease or ulcerative colitis as a concomitant comorbidity (65.8%). The ten-year survival rate was 74.6%. A significantly lower lab-MELD score was identified in patients surviving for > 10 years (15 vs. 22, p = 0.004). Most patients (65%) passed in the first year following transplantation, with primary non-function (PNF), sepsis and arterial thrombosis being the most common causes of death. Donor characteristics did not affect patient survival. Patients with PSC show excellent 10-year survival rates. While the lab-MELD score significantly affected long term outcomes, donor characteristics did not affect survival rates.

Preoperative Computed Tomography Volumetry and Graft Weight Estimation of Left Lateral Segment in Pediatric Living Donor Liver Transplant.

OBJECTIVES: Liver volumetry based on a computed tomography scan is widely used to estimate liver volume before any liver resection, especially before living donorliver donation. The 1-to-1 conversion rule for liver volume to liver weight has been widely adopted; however, debate continues regarding this approach. Therefore, we analyzed the relationship between the left-lateral lobe liver graft volume and actual graft weight. MATERIALS AND METHODS: This study retrospectively included consecutive donors who underwent left lateral hepatectomy for pediatric living donor liver transplant from December 2008 to September 2020. All donors were healthy adults who met the evaluation criteria for pediatric living donor liver transplant and underwent a preoperative contrast-enhanced computed tomography scan. Manual segmentation of the leftlateral liverlobe for graft volume estimation and intraoperative measurement of an actual graft weight were performed. The relationship between estimated graft volume and actual graft weight was analyzed. RESULTS: Ninety-four living liver donors were included in the study. The mean actual graft weight was ~283.4 ± 68.5 g, and the mean graft volume was 244.9 ± 63.86 mL. A strong correlation was shown between graft volume and actual graft weight (r = 0.804; P < .001). Bland-Altman analysis revealed an interobserver agreement of 38.0 ± 97.25, and intraclass correlation coefficient showed almost perfect agreement(r = 0.840; P < .001). The conversion formula for calculating graft weight based on computed tomography volumetry was determined based on regression analysis: 0.88 × graft volume + 41.63. CONCLUSIONS: The estimation of left liver graft weight using only the 1-to-1 rule is subject to measurable variability in calculated graft weights and tends to underestimate the true graft weight. Instead, a different, improved conversion formula should be used to calculate graft weight to more accurately determine donor graft weight-to-recipient body weightratio and reduce the risk of underestimation of liver graft weightin the donor selection process before pediatric living donor liver transplant.