Kianmanesh Reza, Piardi Tullio, Tamby Esther, Parvanescu Alina, Bruno Onorina, Palladino Elisa, Bouché Olivier, Msika Simon, Sommacale Daniele
Department of Digestive Surgery, University of Reims, Reims, France; Department of Digestive Surgery, Louis Mourier University Hospital Centre, University of Paris 7, Paris, France.
HPB (Oxford). 2013 Dec;15(12):976-84. doi: 10.1111/hpb.12079. Epub 2013 Mar 8.
Volumetry is standard method for evaluating the volumes of the right liver (RL), left liver (LL), left lateral segments (LLS), total liver (TL) and future liver remnant (FLR). The aim of this study was to report a simple technique based on measurements of liver angles (angulometry) that can be used to predict liver ratios.
Fifty computed tomography (CT) scans obtained in subjects with normal liver were studied. Four CT scan levels were preselected: level 1 passed by the upper part of the hepatic veins; level 2 passed by the left portal vein branch division; level 3 passed by the right portal vein branch division, and level 4 passed by the gallbladder bed. Left and right tangent lines passing the liver edges were drawn and joined to the centre of the vertebra defining the TL angle. Two lines through, respectively, the plane of the middle hepatic vein and the left portal branches determined the angles of the RL, LL and LLS. Volumetric and angulometric data obtained on levels 2 and 3 in 50 different subjects were compared.
Level 2 CT scans represented the most accurate way of obtaining angulometric measurements. The mean ± standard deviation (SD) angles of the TL and LL were 134 ± 12 ° and 55 ± 12 °, respectively. The mean ± SD percentages of the TL represented by the LL in angulometry and volumetry were 38 ± 7% and 36 ± 6%, respectively (non-significant difference). The mean ± SD percentages of the TL represented by the LLS in angulometry and volumetry were 25 ± 4% and 20 ± 3%, respectively (P < 0.05). The mean ± SD overestimation of the percentage of the TL represented by the LLS in angulometry was 2.7 ± 7.0%.
Angulometry is a simple and accurate technique that can be used to estimate the ratio of the FLR to TL volume on one or two CT (or magnetic resonance imaging) slices. It can be helpful for clinicians, especially before right or extended right hepatectomy and after right portal vein occlusion techniques.
容积测量是评估右肝（RL）、左肝（LL）、左外叶（LLS）、全肝（TL）和未来肝残余量（FLR）体积的标准方法。本研究的目的是报告一种基于肝脏角度测量（角度测量法）的简单技术，可用于预测肝脏比例。
对50例肝脏正常受试者的计算机断层扫描（CT）图像进行研究。预先选择了4个CT扫描层面：层面1通过肝静脉上部；层面2通过左门静脉分支处；层面3通过右门静脉分支处；层面4通过胆囊床。绘制经过肝脏边缘的左右切线，并连接至定义全肝角度（TL角）的椎体中心。分别通过肝中静脉平面和左门静脉分支的两条线确定右肝、左肝和左外叶的角度。比较50例不同受试者在层面2和层面3获得的容积测量和角度测量数据。
层面2的CT扫描是获得角度测量最准确的方法。全肝和左肝的平均±标准差（SD）角度分别为134±12°和55±12°。在角度测量法和容积测量法中，左肝占全肝的平均±SD百分比分别为38±7%和36±6%（无显著差异）。在角度测量法和容积测量法中，左外叶占全肝的平均±SD百分比分别为25±4%和20±3%（P<0.05）。在角度测量法中，左外叶占全肝百分比的平均±SD高估为2.7±7.0%。
角度测量法是一种简单准确的技术，可用于在一张或两张CT（或磁共振成像）切片上估计未来肝残余量与全肝体积的比例。它对临床医生有帮助，尤其是在右半肝或扩大右半肝切除术前以及右门静脉结扎术后。
