Schoepf U Joseph, Schneider Alex C, Das Marco, Wood Susan A, Cheema Jugesh I, Costello Philip
Department of Radiology, Medical University of South Carolina, Charleston, SC 29425, USA.
J Thorac Imaging. 2007 Nov;22(4):319-23. doi: 10.1097/RTI.0b013e31815842a9.
We aimed to evaluate the feasibility and performance of a computer-aided detection (CAD) tool for automated detection of segmental and subsegmental pulmonary emboli.
A CAD tool (ImageChecker CT, R2 Technology, Inc) for automated detection of pulmonary emboli was evaluated on multidetector-row CT studies of varying diagnostic quality in 23 patients (13 female, mean age 52 y) with pulmonary embolism (PE) and of 13 patients (all female, mean age 49 y) without PE. A collimation of 16 x 1 mm and a reconstructed section width of 1.25 mm had been used in each patient. The performance of the CAD tool for the detection of emboli in the segmental and subsegmental pulmonary arterial tree was assessed. Consensus reading of the same studies by 2 radiologists, with a third for adjudication, for the identification of segmental and subsegmental pulmonary emboli was used as the standard of reference.
Consensus reading revealed 130 segmental pulmonary emboli and 107 subsegmental pulmonary emboli in the 23 patients with PE. All 23 patients with PE were correctly identified as having PE by the CAD system. In a vessel-by-vessel analysis, the sensitivity of the CAD algorithm was 92% (119/130) for the detection of segmental pulmonary emboli and 90% (92/107) for subsegmental pulmonary emboli. The overall specificity, positive predictive value (95% confidence interval) and negative predictive value (95% confidence interval) of the algorithm were 89.9%, 63.2% (57.9%-68.2%) and 97.7% (96.7%-98.4%), respectively. The average false positive rate of the CAD algorithm was 4.8 (range 1 to 9) false positive detection marks per case.
CAD of segmental and subsegmental pulmonary emboli based on 1-mm multidetector-row CT studies is feasible. Application of CAD tools may improve the diagnostic accuracy and decrease the interpretation time of computed tomographic angiography for the detection of pulmonary emboli in the peripheral arterial tree and further enhance the acceptance of this test as the first line diagnostic modality for suspected PE.
我们旨在评估一种计算机辅助检测（CAD）工具用于自动检测节段性和亚段性肺栓塞的可行性和性能。
在23例（13例女性，平均年龄52岁）患有肺栓塞（PE）的患者以及13例（均为女性，平均年龄49岁）无PE的患者中，对用于自动检测肺栓塞的CAD工具（ImageChecker CT，R2 Technology公司）在不同诊断质量的多排螺旋CT研究中进行评估。每位患者均采用16×1mm的准直和1.25mm的重建层厚。评估CAD工具在节段性和亚段性肺动脉树中检测栓子的性能。以2名放射科医生对相同研究进行一致性读片，并由第3名医生进行裁决以识别节段性和亚段性肺栓塞，作为参考标准。
一致性读片显示，23例PE患者中有130个节段性肺栓塞和107个亚段性肺栓塞。CAD系统正确识别了所有23例PE患者。在逐血管分析中，CAD算法检测节段性肺栓塞的敏感性为92%（119/130），检测亚段性肺栓塞的敏感性为90%（92/107）。该算法的总体特异性、阳性预测值（95%置信区间）和阴性预测值（95%置信区间）分别为89.9%、63.2%（57.9%-68.2%）和97.7%（96.7%-98.4%）。CAD算法的平均假阳性率为每例4.8个（范围1至9个）假阳性检测标记。
基于1mm多排螺旋CT研究的节段性和亚段性肺栓塞CAD是可行的。CAD工具的应用可能会提高诊断准确性，减少计算机断层血管造影对周围动脉树中肺栓塞检测的解读时间，并进一步提高该检查作为疑似PE一线诊断方法的接受度。
