双能CT虚拟平扫鉴别良恶性孤立肺结节的临床应用价值  

Dual-energy CT in the evaluation of solitary pulmonary nodules by virtual non-enhanced images： initial experience

作　　者：郭兴[1] 丁伟[1] 秦慧娟[1] 

机构地区：[1]长治医学院附属和平医院影像科,046000

出　　处：《中华放射学杂志》2011年第9期846-849,共4页Chinese Journal of Radiology

摘　　要：目的探讨双能CT虚拟平扫技术鉴别孤立性肺结节（SPN）良恶性的准确性及辐射剂量。方法61例SPN患者，其中经病理证实恶性39例，良性18例。经对比增强双能CT扫描，使用LiverVNC处理程序测量虚拟平扫图像和增强图像中SPN的CT值，同时获得两者差值。将CT值差值／〉20HU的SPN确定为恶性，计算诊断准确性。使用配对t检验对其中28例患者的常规CT平扫和虚拟平扫图像的噪声进行评价（1～5）分，使用Mann—WhitneyU检验对图像质量及每例患者的辐射剂量进行评价。结果使用虚拟平扫图像为基线进行SPN良、恶性判断的敏感度、特异度、准确度分别为89．7％（35／39）、72．2％（13／18）、84．2％（48／57）。常规平扫图像和虚拟平扫图像的噪声分别为（8．49±1．94）、（10．14±2．18）HU，t=9．45，P〈0．01；图像质量评分分别为（4．71±0．46）、（4．42±0．57）分，U=290．00，P〉0．05。单次常规平扫和双能CT扫描患者接受辐射的有效剂量分别为（3．72±0．48）、（3．78±0．45）mSv，U=350．50，P〉0．05。结论双能CT胸部扫描可有效降低对患者的放射性辐射；以虚拟平扫图像为基线判断SPN的良恶性具有较高的准确性。Objective To determine the accuracy and radiation dose of dual-energy computed tomography （CT） in evaluating solitary pulmonary nodules （SPNs） by virtual non-enhanced images. Methods Sixty-one patients with SPNs including 39 malignant and 18 benign nodules proved by pathology underwent DECT scans. The CT values of SPNs on enhanced weighted average and virtual non-enhanced images were compared by using Liver VNC processing unit in terms of their diagnostic accuracy for distinguishing malignant and benign nodules with a 20 HU threshold. Diagnostic accuracy was compared. In 28 patients of all patients, image noise and quality score of the non-enhanced and virtual non-enhanced images were compared, and radiation doses of each patient were recorded. The paired t test was used to analyze the noise difference between the plain scan and virtual non-enhanced scan. The Mann-Whitney U test was used to analyze statistically significant differences of the image quality score and radiation dose between the non-enhanced scan and virtual non-enhanced scan. Results The sensitivity, specificity and accuracy for distinguishing benign and malignant nodules by using the virtual non-enhanced image of were 89.7% （35/39）, 72. 2% （ 13/18 ）, 84. 2% （48/57） respectively. The noise of common CT and virtual nonenhanced images were （8.49 ± 1.94 ） HU and （10. 14 ± 2. 18 ） HU, and there were statistically difference （t =9.45,P 〈0. 01 ）. The quality scores of common CT and virtual non-enhanced images were （4. 71 ±0.46） and （4. 42 ±0. 57 ）, and there were no statistical difference （ U = 290.00, P 〉 0. 05 ）. The radiation doses of common CT and DECT were （ 3.72 ± 0. 48 ） rosy and （ 3.78 ± 0.45 ） mSv, and there were no statistical difference （ U = 350. 50,P 〉 0.05 ）. Conclusion DECT by using virtual non-enhanced images is useful tool to distinguish the benign and malignant SPN without additional radiation dose.

关 键 词：硬币病变 肺 体层摄影术 X线计算机 图像处理 计算机辅助 

分 类 号：R816.4[医药卫生—放射医学]