Plenary: Next Frontier, Sunday, Afternoon Session
Presentation Authors: Joon Yau Leong*, Corinne Wessner, Michael Kramer, Flemming Forsberg, Andrej Lyshchik, Edouard Trabulsi, Costas Lallas, John Eisenbrey, Philadelphia, PA
Introduction:Vascular assessment of indeterminate renal masses (iRM) remains a crucial element of diagnostic imaging as the presence of blood flow within renal lesions suggests malignancy. Superb microvascular imaging (SMI) is a novel Doppler technique capable of detecting lower blood flow velocities. This study compared the utility of color and monochrome SMI (cSMI and mSMI) to color and power Doppler imaging (CD and PD) for the detection of microvasculature within iRM.
Methods: Patients undergoing contrast-enhanced ultrasound (CEUS) evaluation for iRM from 10/9/2018-1/17/2019 provided informed consent to participate in this ongoing IRB approved study. CD, PD, cSMI and mSMI was performed prior to CEUS using an Aplio i800 with an i8CX1 transducer (Canon Medical Systems, Tustin, CA). For each lesion, a mean of 5 images were captured for each imaging mode. Following data acquisition, a total of 4 sets of images, each consisting of all images with a single modality, was randomized and read by a blinded sonographer. Each mode was assessed for the presence of internal vascularity within the lesion and for diagnostic confidence on a scale of 1-5 (5 = most confident). Sensitivity, specificity and predictive values were calculated for iRM vascularity using CEUS as the reference standard.
Results: 25 patients with 29 lesions met inclusion criteria. The mean age was 65.6±11.8 years while the maximum lesion diameter was 2.8±1.9 cm. cSMI had the highest sensitivity (75%) when compared to CD, PD and mSMI (31-56%), while mSMI had the highest specificity (85%) and positive predictive value (71%) when compared to CD, PD and cSMI (46-54% and 60-63% respectively). cSMI also had the highest negative predictive value (60%) and accuracy (62%) relative to the other 3 imaging modalities (all 50% and all 55% respectively). While the confidence level of mSMI (3.4±0.7) was significantly lower than CD (4.0±0.8) and PD (3.9±0.8) (p<0.01), the confidence level of cSMI (3.9±0.9) was not (p>0.38).
Conclusions: Preliminary data suggests that SMI is a potentially useful modality in detecting microvasculature in iRM when compared to standard Doppler techniques. Future studies should aim to compare the efficacy of both SMI and CEUS and to assess the ability of SMI to characterize malignancy in iRM.
Source of Funding: None