Abstract: Objective By comparing with digital subtract angiography (DSA), to prospectively evaluate the value of dual-input CT perfusion (DI-CTP) technique in detecting systemic artery-pulmonary artery fistula among patients with massive hemoptysis due to pulmonary tuberculosis (TB).   Methods Twelve pulmonary TB patients with massive hemoptysis underwent dual-input lung perfusion CT examination before DSA was performed. The parameters of DI-CTP at every segment of lung were recorded. And then, DSA results was used as a golden standard and the receiver-operating characteristic (ROC) curve analysis was performed to evaluate the effectiveness of DI-CTP technique in detecting systemic arterial-pulmonary arterial fistula and to determine the optimal perfusion para-meters (including pulmonary flow, PF; bronchial flow, BF and perfusion index, PI) with the corresponding diagnostic threshold, sensitivity and specificity.   Results A total of 216 lung segments were measured in 12 patients. Among them, 70 segments were confirmed to be positive (i.e. systemic artery-pulmonary artery fistula was made) by DSA while 146 segments were negative. The areas under ROC curves for PF, BF and PI were 0.697, 0.138 and 0.941 respectively; thus the area under ROC curve for PI was largest (P<0.001). So the PI was the optimum parameter and its diagnostic threshold was 96.25 with 88.00% sensitivity and 87.00% specificity.  Conclusion DI-CTP is valuable in detecting systemic artery-pulmonary artery fistula among pulmonary TB patients with hemoptysis, and can be used as a screening method before embolotherapy with DSA.

Key words: Tuberculosis, pulmonary/complications, Hemoptysis, Arterio-arterial fistula, Pulmonary artery, Tomography, X-ray computed, Perfusion