Application Explore Of Triple-enhanced Targeted Scan Of MSCT In Differential Diagnosing Of Solitary Pulmonary Nodules

Objective:to explore characteristic,type and mechanism of Triple-phase enhanced targeted scan with MSCT of solitary pulmonary nodules,research the clinical diagnostic value;improve the accuracy of qualitative diagnosis of solitary pulmonary nodules.Methods:to collect 67 patients with solitary pulmonary nodules(SPN)which diameter≤3CM(including 41 malignant SPN,26 benign SPN)from April,2006 to April,2007,their were confirmed by operation,pathohistology or clinic follow-up.All patients were performed firstly routine spiral scan with 16-row detector CT(siemens samatom sensation 16),then were performed SPN located targeted scan,slice thickness is≤5mm.Thirdly,20ml Ultravist(300mgI/ml)was injected at a rate of 3.5ml/s via forearm superficial vein by a high-press injector,perform testbolus scan,the peak CT values in pulmonary artery and aorta were to determine the delay time for the acquisition in pulmonary phase and aortal phase.Finally,according to 1.3ml/kg weight inject Ultravist at the same rate by a high-press injector,perform SPN scan in pulmonary phase,aortal phase and delay phase(ie triple-phase enhanced targeted scan)at the same method as SPN located targeted scan,delay time is 5 min.Results:the differences of net increased CT value in three phases were statistically significant respectively between maligant SPN and benign SPN(F=86.921,7.887 and 19.224 respectively;P=0.000,0.007 and 0.000 respectively).If the net increased value＞20HU was set as a diagnostic threshold,accuracy is 64.2%;When net increased CT value≥20HU in aortal phase while net increased CT value＜20HU in pulmonary phase was set as a diagnostic threshold,accuracy is 80.6%;only if neoplastic blood vessels were set as a Indicators for the diagnosis of maligant SPN,is accuracy 77.6%;when net increased CT value≥20HU in aortal phase while net increased CT value＜20HU in pulmonary phase or the existence of neoplastic blood vessel were regarded as a diagnostic threshold,accuracy is 92.5%which is the highest.Conclusion:to perform SPN scan with MSCT,the net increased CT values of every phase in the triple-phase enhanced targeted scan combine neoplastic blood vessels is helpful of the diagnosis and differential diagnosis of SPN.