Introduction: Knowledge about venous patterns (especially portal and hepatic venous) and their variations are extremely crucial for liver transplantation and other surgical procedures on liver. Studies have been done at national or international level on variations of hepatic venous patterns by CT or MRI or by dissection on cadaveric liver. No definitive or authentic study on this topic could be noted in electronic and print media, as well as in standard textbook. Considering low cost and noninvasive nature, we utilized ultrasonography to bridge this lacuna. Aim: To estimate prevalence and types of anatomical variations of hepatic venous system and to determine association of among variations. Materials and methods: It is an observational cross-sectional study where ultrasonographic evaluation of hepatic venous pattern on adult population of either sex (consecutive sampling) without any major liver disorders was done in RG Kar Medical College and data were analyzed with appropriate statistical procedures. Results: Normal hepatic venous pattern along with normal portal venous pattern is much higher in our study, which is a unique finding. The proportion of normal portal venous pattern is more in extra hepatic bifurcation group. Variations of portal vein and normal hepatic venous pattern are more in case of intrahepatic bifurcation of portal venous branching group. Overall presence of intrahepatic bifurcation of portal vein is significantly higher than extrahepatic bifurcation. Conclusions: This study provides an updated database for the prevalence and distribution of anatomic variations of the hepatic venous and portal venous system.

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.