LAUSR

In late 1895,Wilhelm Roentgen ignited a disease diagnostics revolution with the discovery of x-rays, which opened a new era for medical imaging. Imaging is swiftly evolving from being primarily a disease diagnostic tool to also having an indispensable role in the context of personalized management. Nowadays, liver imaging has been routinely performed in clinical practice, and emerging relevant techniques further accelerate its application in precision medicine. Liver imaging for determining disease etiology, and for staging advanced fibrosis and cirrhosis, was comprehensively discussed in a New England Journal of Medicine paper in December 2017. Although imaging approaches have not replaced liver biopsy yet, they have sharply reduced the demand for invasive procedures. This is also true for risk stratification of portal hypertension in compensated advanced chronic liver disease. Imaging evidence of portocollateral circulation or a flow reversal is sufficient to diagnose clinically significant portal hypertension. However, the low sensitivity of liver imaging makes it difficult for the early diagnosis and primary prophylaxis of portal hypertension bleeding. Hepatic venous pressure gradient (HVPG) is currently the only validated approach to stratify the risk of portal hypertension, but its invasiveness, cost, and requirement for specific equipment have hindered the routine and wider use of HVPG in practice. The computed tomography imaging-based three-dimensional (3D) modeling combined with computational fluid dynamics in the CHESS1601 trial have made it possible to develop a noninvasive surrogate of HVPG. Additionally, magnetic resonance hemodynamic parameters have also showed a satisfactory correlation with HVPG. Taken together, imaging techniques have greatly improved our ability to precisely diagnose liver diseases. However, heterogeneity across studies of imaging tools generated from different etiologies and populations cannot be ignored. We would like to particularly underline the need for reliable liver imaging techniques that are able to monitor HVPG changes, because this is an unmet need with major clinical implications. Liver imaging also contributes to a novel paradigmof “precision liver surgery”, featuring certain surgical interventions-guiding precise management. Precision liver surgery integrates advanced imaging techniques, eg, imaging-based 3D visualization, and equips the surgeon with real anatomy of the liver including the location of lesions, the traverse and territory of vessels, and the spatial relationship between