scanning planes is mandatory to cover all segments and the complete liver surface The patient should be examined from sub- and intercostally in the decubitus position as well in modified slightly oblique positions with the right arm above the head and the right leg stretched during all respiration cycles to identify the best approach and to avoid artifacts caused by the thorax. Examination in the standing position is additionally helpful due to its weight, the liver moves caudally by gravity, and scanning from sub- or intercostal probe positions according to the individual anatomy-avoides the interposed lung which is mainly true for the right posterolateral (superficial) parts of the liver using the intercostal approach. Other examination techniques have also been described but are not mentioned here in detail which might be additionally used a great number of variants of the normal has to be encountered -e.g. with respect to accessory lobules, vascular branching, shape and configuration Examination criteria An acronym has shown to be didactically helpful ["SSOTM] ·S=size o=outline T=texture measurement The size of the liver has been measured by many methods, including 3D-reconstructions. Liver size measurement has no impact in daily routine because there is no reliable and reproducible ultrasound method established so far sh normally described as pyramidal Outline The normal liver surface should be smooth with no lumps protruding or indentations The inferior liver border in the normal patient should have an acute angled edg Liver surface border delineation and other ultrasound criteria: Other ultrasound criteria are described in the respective chapters Texture, echogenicity The normal liver parenchyma is of medium homogenous echogenicity, usually slightly darker than the spleen and slightly brighter than the renal cortex independently of the age except in childhood [(32)]. It is essential when comparing the liver with the spleen and renal cortex that the comparison is done at the same depth. Liver surface and vessels borders are smooth and vascular architecture with its classic dichotomy in branching is percepted as a harmonic and detailed aspect. The image of the normal parenchyma varies very little among individual Liver veins The three liver veins are positioned in between the liver segments. Their course additionally to the Glisson's triad- is helpful in defining liver lobes and liverscanning planes is mandatory to cover all segments and the complete liver surface. The patient should be examined from sub- and intercostally in the decubitus position as well in modified slightly oblique positions with the right arm above the head and the right leg stretched during all respiration cycles to identify the best approach and to avoid artifacts caused by the thorax. Examination in the standing position is additionally helpful due to its weight, the liver moves caudally by gravity, and scanning from sub- or intercostal probe positions – according to the individual anatomy - avoides the interposed lung which is mainly true for the right posterolateral (superficial) parts of the liver using the intercostal approach. Other examination techniques have also been described but are not mentioned here in detail which might be additionally used. A great number of variants of the normal has to be encountered – e.g. with respect to accessory lobules, vascular branching, shape and configuration. Examination criteria An acronym has shown to be didactically helpful [“SSOTM”]: • S = size • S = shape • O = outline • T = texture • M = measurement Size The size of the liver has been measured by many methods, including 3D-reconstructions. Liver size measurement has no impact in daily routine because there is no reliable and reproducible ultrasound method established so far. Shape Normally described as pyramidal. Outline The normal liver surface should be smooth with no lumps protruding or indentations. The inferior liver border in the normal patient should have an acute angled edge. Liver surface border delineation and other ultrasound criteria: Other ultrasound criteria are described in the respective chapters. Texture, echogenicity The normal liver parenchyma is of medium homogenous echogenicity, usually slightly darker than the spleen and slightly brighter than the renal cortex independently of the age except in childhood [(32)]. It is essential when comparing the liver with the spleen and renal cortex that the comparison is done at the same depth. Liver surface and vessels borders are smooth and vascular architecture with its classic dichotomy in branching is percepted as a harmonic and detailed aspect. The image of the normal parenchyma varies very little among individuals. Liver veins The three liver veins are positioned in between the liver segments. Their course - additionally to the Glisson`s triad - is helpful in defining liver lobes and liver