Shiotani Seiji, Kohno Mototsugu, Ohashi Noriyoshi, Yamazaki Kentaroh, Nakayama Hidetsugu, Ito Yoshiyuki, Kaga Kazunori, Ebashi Toshio, Itai Yuji
Department of Radiology, Tsukuba Medical Center Hospital, Ibaraki, Japan.
Radiat Med. 2002 Jul-Aug;20(4):201-6.
To quantitatively evaluate the finding of hyperattenuating aortic wall on postmortem computed tomography (PMCT) and investigate its causes.
Our subjects were 50 PMCT of non-traumatic deaths and 50 CT of living persons (live CT). The ascending aorta at the level of the carina was visually assessed regarding the presence or absence of hyperattanuating aortic wall and hematocrit effect on PMCT and live CT. The diameter, thickness of the aortic wall, and CT number (HU) of the aortic wall and the lumen were also measured.
Hyperattenuating aortic wall was detected in 100% of PMCT and 2% of live CT. The diameter of the aortic wall was 2.9 +/- 0.5 cm on PMCT and 3.5 +/- 0.5 cm on live CT, showing a significant difference. The thickness of the aortic wall was 2 mm on PMCT. Hematocrit effect was observed in 46% of PMCT and in none of live CT. With PMCT, there was a significant difference between the CT numbers of the upper and lower half portions of the lumen (19.6 +/- 11.7/30.9 +/- 12.9), whereas, with live CT, there was no such significant difference (37.4 +/- 7.6/38.9 +/- 6.7), with the overall value of 38.2 +/- 6.7. The CT number of the aortic wall was 49.9 +/- 10.9 on PMCT.
The causes of hyperattenuating aortic wall on PMCT are considered to be increased attenuation due to contraction of the aortic wall, a lack of motion artifact, and decreased attenuation of the lumen due to dilution of blood after massive infusion at the time of cardiopulmonary resuscitation.
定量评估尸检计算机断层扫描（PMCT）上主动脉壁高密度影的表现，并探究其成因。
我们的研究对象包括50例非创伤性死亡的PMCT以及50例活人计算机断层扫描（活体CT）。在隆突水平对升主动脉进行观察，判断是否存在主动脉壁高密度影以及血细胞比容对PMCT和活体CT的影响。同时测量主动脉壁的直径、厚度以及主动脉壁和管腔的CT值（HU）。
在100%的PMCT中检测到主动脉壁高密度影，而在2%的活体CT中检测到。PMCT上主动脉壁直径为2.9±0.5cm，活体CT上为3.5±0.5cm，差异显著。PMCT上主动脉壁厚度为2mm。46%的PMCT观察到血细胞比容效应，而活体CT中未观察到。对于PMCT，管腔上下半部分的CT值存在显著差异（19.6±11.7/30.9±12.9），而对于活体CT则无显著差异（37.4±7.6/38.9±6.7），总体值为38.2±6.7。PMCT上主动脉壁的CT值为49.9±10.9。
PMCT上主动脉壁高密度影的成因被认为是主动脉壁收缩导致的衰减增加、缺乏运动伪影以及心肺复苏时大量输液后血液稀释导致管腔衰减降低。
