Accuracy of the Chula's formula for calculation of standard liver volume in Thai population

Background: Standard liver volume (SLV) is an important concept in living donor liver transplantation for treatment of end-stage liver disease. Accurate estimation of the SLV of living donor and recipient is crucial to ensure optimal graft function and avoid complications. Objective: 1) to assess the proposed formula for calculation of SLV in Thai population, using computed tomography (CT) volumetric measurement as a gold standard. 2) to evaluate the factors (e.g. age, sex, body weight and body surface area) related to differences between SLV calculated from the proposed formula and CT volumetric measurement. Materials and methods: We evaluated 497 patients underwent contrast-enhanced abdominal multi-detector CT for conditions unrelated to hepatobiliary system with normal liver radiology between October 1, 2014 and August 31, 2015 were included. Calculated SLV by the proposed formula (SLV = 20.76 x body weight) were compared to the total liver volume (TLV) measured from multi-detector CT by using computerized tool automatically. Factors related to the difference between SLV and TLV were evaluated. Result: The aforementioned formula showed a high accuracy in estimating the liver volume with some limitations in overweight or underwent patients. The mean difference between SLV and TLV is 3.36 cm3 with SD of 224.65 cm3. Conclusion: We proposed a new formula ("Chula's standard liver volume") that demonstrates a high accuracy for calculation of SLV in Thai population. Keywords: Liver volume; MDCT; standard liver volume; Thai population

Standard Liver Volume-Predicting Formulae Derived From Normal Liver Volume in Children Under 18 Years of Age

Background: Standard liver volume (SLV) is important in risk assessment for major hepatectomy. We aimed to investigate the growth patterns of normal liver volume with age and body weight (BW) and summarize formulae for calculating SLV in children.Methods: Overall, 792 Chinese children (<18 years of age) with normal liver were enrolled. Liver volumes were measured using computed tomography. Correlations between liver volume and BW, body height (BH), and body surface area (BSA) were analyzed. New SLV formulae were selected from different regression models; they were assessed by multicentral validations and were compared.Results: The growth patterns of liver volume with age (1 day−18 years) and BW (2–78 kg) were summarized. The volume grows from a median of 139 ml (111.5–153.6 in newborn) to 1180.5 ml (1043–1303.1 at 16–18 years). Liver volume was significantly correlated with BW (r = 0.95, P < 0.001), BH (r = 0.92, P < 0.001), and BSA (r = 0.96, P < 0.001). The effect of sex on liver volume increases with BW, and BW of 20 kg was identified as the optimal cutoff value. The recommended SLV formulae were BW≤20 kg: SLV = 707.12 × BSA1.09; BW>20 kg, males: SLV = 691.90 × BSA1.06; females: SLV = 663.19 × BSA1.04.Conclusions: We summarized the growth patterns of liver volume and provided formulae predicting SLV in Chinese children, which is useful in assessing the safety of major hepatectomies.

Variability of Standard Liver Volume by 2D Ultrasound: A Cross-sectional Study from Eastern India

Introduction: Liver volume estimation is an essential component prior to major hepatic surgery and liver transplantation. Liver volume is evaluated with different formulae, gold standard Computed Tomography (CT) volumetry and Magnetic Resonance Imaging (MRI). As per literature review, studies comparing ultrasonography with formula based liver volume estimation are very few. Ultrasonography is non-invasive in nature and inexpensive. It is gaining popularity among clinicians as it helps in rapid evaluation of liver volumes. Aim: To compare variability of liver volume using 2D ultrasound with a standard well-established method based on formula derived by Johnson et al. Materials and Methods: This was a cross-sectional study done between August-October 2020 and patients were selected by the physician from general Outpatient Department (OPD) pool and clinically screened for further biochemical studies. Participants aged 20-60 years with normal liver function test were recruited in the study. Images were taken on a Siemens Ultrasound System. Study variables included were liver volumes estimated by two methods, age, weight, height and Body Surface Area (BSA). F test was used to compare variability between liver volumes estimated by two different methods. Bivariate correlation between ultrasonography-based liver volume and different body indices was also tested. Results: Variability comparison using F test shows no significant difference (F=1.095, df1=149, df2=149, p=0.29). Liver volumes estimated by two methods showed good correlation with each other and is significant at the 0.01 level, r=0.574. The mean difference (125 cc) in volumes between two methods were statistically significant (t=10.92, degree of freedom=149, p<0.001) and were not in agreement with each other. Body parameters were correlated with liver volume estimated by 2D ultrasound. Conclusion: Ultrasonography is a useful tool in estimating liver volume prior to major hepatic resection. Formula based calculation of Standard Liver Volume (SLV) does not agree with USG based volume and underestimates the mean liver volume obtained by USG method.