CAJ | 학술논문

目的：探讨双源CT双能量虚拟平扫（VNC）技术在结直肠病变诊断中应用的可行性。资料与方法对85例临床疑诊结直肠病变患者行腹部CT平扫及动、静脉期双能量增强扫描，经双能软件处理得到动、静脉期VNC图，比较真实平扫与VNC在图像质量、辐射剂量及诊断符合率方面的差异。结果双能双期扫描辐射剂量较常规三期扫描辐射剂量降低约34.8%。VNC CT值在肠道病变、转移淋巴结、肠周脂肪中低于真实平扫（P<0.05或P<0.01），而在肝脏及肝转移灶高于真实平扫（P<0.01），动、静脉期VNC无明显差异（P>0.05）。真实平扫及动、静脉期VNC观察到的肠壁厚度、淋巴结大小、周围侵犯及肝转移差异无统计学意义（P>0.05），对肠道疾病的诊断符合率差异无统计学意义（P>0.05）。VNC噪声低于真实平扫（P<0.05），信噪比、对比噪声比高于真实平扫，图像评分与真实平扫差异无统计学意义（P>0.05）。结论对于结直肠病变，双源CT双能量VNC技术可在保证图像质量、不影响病变诊断的前提下降低辐射剂量。
목적：탐토쌍원CT쌍능량허의평소（VNC）기술재결직장병변진단중응용적가행성。자료여방법대85례림상의진결직장병변환자행복부CT평소급동、정맥기쌍능량증강소묘，경쌍능연건처리득도동、정맥기VNC도，비교진실평소여VNC재도상질량、복사제량급진단부합솔방면적차이。결과쌍능쌍기소묘복사제량교상규삼기소묘복사제량강저약34.8%。VNC CT치재장도병변、전이림파결、장주지방중저우진실평소（P<0.05혹P<0.01），이재간장급간전이조고우진실평소（P<0.01），동、정맥기VNC무명현차이（P>0.05）。진실평소급동、정맥기VNC관찰도적장벽후도、림파결대소、주위침범급간전이차이무통계학의의（P>0.05），대장도질병적진단부합솔차이무통계학의의（P>0.05）。VNC조성저우진실평소（P<0.05），신조비、대비조성비고우진실평소，도상평분여진실평소차이무통계학의의（P>0.05）。결론대우결직장병변，쌍원CT쌍능량VNC기술가재보증도상질량、불영향병변진단적전제하강저복사제량。
Purpose To assess the feasibility of applying dual-energy dual-source CT virtual non-contrast (VNC) imaging in the diagnosis of colorectal diseases. Materials and Methods Eighty-ifve patients with clinically suspected colorectal lesions underwent abdominal CT scan as well as arterial and venous phase dual-energy enhanced scan, VCN images of arterial and venous phase were obtained using the dual-energy software, the differences of image quality, radiation dose and diagnostic coincidence rate between the true non-contrast scan and VNC images were compared. Results The radiation dose of two-phase dual-energy scan was 34.8%lower when compared with the conventional three-phase scans. The CT values of the intestinal lesions, metastasis lymph nodes and intestinal fat in VNC were lower than the true unenhanced scan (P<0.05 or P<0.01), whereas were higher than the real scan in liver and liver metastases (P<0.01), there was no signiifcant difference of VNC between the arterial and venous phase. Differences of intestinal wall thickness, metastasis lymph node size, peripheral invasion and liver metastases observed from real non-contrast scan and VNC were not statistically significant (P>0.05), and neither was the diagnostic coincidence rate for intestinal diseases (P>0.05). The noise level of images obtained from VNC was lower than that of the real non-contrast scan (P<0.05), with higher SNR and CNR, there was no signiifcant difference of image scoring among the three groups (P>0.05). Conclusion For colorectal lesions, the virtual non-contrast images from the dual-energy dual-source CT scan can be used to reduce the radiation dose without effecting image quality and diagnosis accuracy.