Value of contrast-enhanced ultrasound in diagnosis of renal epithelioid angiomyolipoma

Abstract

Objective To investigate the value of contrast-enhanced ultrasound (CEUS) in diagnosis of renal epithelioid angiomyolipoma (eAML).Methods The CEUS features of 18 patients with 18 histopathologically proved renal eAMLs were retrospective analyzed using both of qualitative and quantitative approachs.Tumor conventional ultrasound and CEUS features were observed.The Sonoliver software was applied to perform quantitative analysis,which provided five parameters,including the maximum intensity (IMAX),rise time (RT),time to peak (TTP),mean transit time (mTT) and area under the curve (AUC).Results All of 18 lesions were pathological proved as eAML,among them,heterocyst was observed in 7 lesions,1 lesion had dissemination inter-kidney and vessel invasion,necrosis or cystic degeneration was found in 3 eAMLs.On conventional ultrasound,eAML showed hypoecho,isoecho and hyperecho were 14(77.8％),3(16.7％) and 1 (5.6％) respectively.Blood flow could be detected in 16 (88.9％) lesions.On CEUS,the characters of slow-in,synchronous-in,slow centripetal enhancement and entire enhancement were observed in 10 (55.6％),8 (44.4％),8 (44.4％) and 12 (55.6％) lesions,respectively.Most of eAMLs showed homogeneous enhancement (15/18,83.3％) and hyper-or iso-enhancement (16/18,88.8 ％) at peak time.The characters of fast-out,synchronous-out and slow out were observed in 8 (44.4％),2 (11.2％) and 8 (44.4％) cases,respectively.Pseudocapsule was detected in 5 (27.8％) lesions.The parameters of RT,TP and AUC for eAMLs were higher than that for renal cortex (P ＜ 0.05),while the parameters of IMAX and mTT had no significant statistical difference between eAMLs and renal cortex(P ＞0.05).Conclusions Qualitative and quantitative analysis of CEUS reflect the blood perfusion of eAMLs in different aspect,which offer some useful informations for the diagnosis of eAMLs. Key words: Ultrasonography ; Microbubbles ; Renal neoplasms ; Angiomyolipoma