The Role Of Contrast-enhanced Ultrasound Combined With Biopsy And Elastography In Diagnosis Of Peripheral Pulmonary Lesions

Objective To explore the value of contrast-enhanced ultrasound?CEUS?combined with percutaneous biopsy in the diagnosis of peripheral pulmonary lesions and to evaluate the diagnostic efficiency of CEUS with tumor markers in peripheral lung cancer.Also,to investigate the potential clinical utility of elastography in diagnosing peripheral lung lesions.Methods A total of 181 patients with peripheral pulmonary lesions underwent ultrasound-guided percutaneous puncture biopsy.Among them,110 cases underwent CEUS before biopsy?experiment group?,and 71 cases underwent conventional ultrasound?control group?.All lesions'conventional ultrasound findings,such as location,size,shape and internal echogenicities,were recorded.Puncture times,positive rate of samples pathological diagnosis and occurrence rate of complications were compared between experiment and control group.According to pathological results,the experiment group was further divided into benign and malignant group.After contrast agent injection,arrive time?AT?in the lesion,difference of AT between the lesion and lung(t_AT),and lesion's enhanced morphology were observed.The time intensity curve?TIC?was used to obtain the rise time?RT?,mean transit time?MTT?,time from peak to one half?TPH?,time to peak?TTP?,peak intensity?PI?and wash-in slope?WIS?.The parameters of TIC between the two groups were compared.Serum carcinoembryonic antigen?CEA?,neuron specific enolase?NSE?and cytokeratin 19fragment?CYFRA21-1?level were detected and analyzed between the two groups.Acoustic radiation force impulse imaging?ARFI?was performed in some lesions in benign and malignant group.The shear wave velocity?SWV?of lesions was calculated and analyzed between the two group.Results Of all 181 cases,166 were made a definite pathologic diagnosis?105cases in experiment group and 61 in control group?.Lesions'shape and intralesional bronchial syndrome had significant difference in the diagnosis of peripheral pulmonary benign and malignant lesions?P<0.01?.The positive rate of samples pathological diagnosis was 95.45%?105/110?in experiment group and 85.92%?61/71?in control group.The difference of the positive rate was significant between two groups?P<0.05?.In experiment and control group,the average puncture times was2.03±0.43 and 2.19±0.42;while the occurrence rate of complications was 1.82%and4.23%?P>0.05?,respectively.In benign group,27 lesions?54.00%,27/50?were enhanced in late pulmonary arterial phase and 32 lesions?64.00%,32/50?showed homogeneous enhancement.At the meantime,in malignant group,most of lesions?76.36%,42/55?were enhanced in bronchial arterial phase and 36.00%?18/50?of lesions indicated inhomogeneous enhancement.The difference of enhanced phase and morphology between benign and malignant lesions were of statistical significance?all P<0.05?.While the statistical differences of such quantitative parameters AT,t_AT,RT,TTP,PI and WIS were found between benign and malignant lesions?all P<0.05?in experiment group,but no statistical difference of MTT and TPH were found?all P>0.05?.In the diagnosis of peripheral lung cancer,the accuracy and specificity of t_ATT combined with joint detection of 3 kinds of tumor markers was 76.37%and 75.00%,respectively,and higher than any single detection,but sensitivity was a little lower?76.47%?.32 cases in experiment group were selected to undergo ARFI examination.SWV was significantly lower in benign group than in malignant?P<0.01?.The cut-off value of SWV was 4.25m/s for the differentiation between benign and malignant lesions,showing a sensitivity of 83.33%,specificity of 85.71%,positive predictive value?PPV?of 88.23%,and negative predictive value?NPV?of 80.00%.Conclusion CEUS quantitative analysis has certain value in the diagnosis of benign and malignant peripheral lung lesions and combined with tumor markers can improve the diagnostic efficiency of peripheral lung cancer.CEUS also has a significant value in guiding percutaneous biopsy in peripheral pulmonary lesions since it could show its microvascular perfusion.As a kind of elastography technique,ARFI is helpful in differentiating benign and malignant peripheral pulmonary lung lesions.