Institute of Diagnostic Radiology, Department of Radiology, University Hospital of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland.
Eur J Radiol. 2010 Jul;75(1):e107-11. doi: 10.1016/j.ejrad.2009.09.005. Epub 2009 Sep 25.
To compare virtual volume to intraoperative volume and weight measurements of resected liver specimen and calculate appropriate conversion factors to reach better correlation.
Preoperative (CT-group, n=30; MRI-group, n=30) and postoperative MRI (n=60) imaging was performed in 60 patients undergoing partial liver resection. Intraoperative volume and weight of the resected liver specimen was measured. Virtual volume measurements were performed by two readers (R1,R2) using dedicated software. Conversion factors were calculated.
Mean intraoperative resection weight/volume: CT: 855 g/852 mL; MRI: 872 g/860 mL. Virtual resection volume: CT: 960 mL(R1), 982 mL(R2); MRI: 1112 mL(R1), 1115 mL(R2). Strong positive correlation for both readers between intraoperative and virtual measurements, mean of both readers: CT: R=0.88(volume), R=0.89(weight); MRI: R=0.95(volume), R=0.92(weight). Conversion factors: 0.85(CT), 0.78(MRI).
CT- or MRI-based volumetry of resected liver specimen is accurate and recommended for preoperative planning. A conversion of the result is necessary to improve intraoperative and virtual measurement correlation. We found 0.85 for CT- and 0.78 for MRI-based volumetry the most appropriate conversion factors.
比较虚拟体积与术中切除肝脏标本的体积和重量测量值，并计算适当的转换系数以达到更好的相关性。
对 60 例行部分肝切除术的患者进行术前 CT 组（n=30）和 MRI 组（n=30）以及术后 MRI（n=60）成像。测量切除肝脏标本的术中体积和重量。由两位读者（R1，R2）使用专用软件进行虚拟体积测量。计算转换系数。
平均术中切除重量/体积：CT：855 克/852 毫升；MRI：872 克/860 毫升。虚拟切除体积：CT：960 毫升（R1），982 毫升（R2）；MRI：1112 毫升（R1），1115 毫升（R2）。两位读者的术中与虚拟测量之间均呈强正相关，两位读者的平均值：CT：R=0.88（体积），R=0.89（重量）；MRI：R=0.95（体积），R=0.92（重量）。转换系数：0.85（CT），0.78（MRI）。
基于 CT 或 MRI 的切除肝脏标本体积测量准确，推荐用于术前计划。需要转换结果以提高术中与虚拟测量的相关性。我们发现 CT 基于 0.85 和 MRI 基于 0.78 的体积测量是最合适的转换系数。
