摘要
Prostatic artery embolization(PAE)has gained acceptance as a minimally invasive,safe and effective treatment of symptomatic benign prostatic hyperplasia.Radiologic imaging is an indispensable part of post-interventional evaluation of PAE and serves both clinical and investigational purposes.In this context,ultrasonography(US)has a central and multifaceted role.Gray-scale US is routinely utilized for measurement of significant outcome parameters(prostatic volume,intra-vesical prostatic protrusion and post-void residual volume)before and after PAE.Improvement of these parameters may become more obvious onemonth post-PAE,or later.Contrast-enhanced US(CEUS)with intravenous administration of a second-generation echo-enhancer can demonstrate prostatic infarcts(as enhancement defects)immediately post-PAE and monitor their resolution over time.The volume of prostatic infarcts can also be measured and compared to prostatic volume.Prostatic infarction is a definite sign of the local efficacy of PAE and a predictor of prostate shrinkage and(at least in some patients)of clinical success.CEUS can also be performed intraoperatively in the angio-suite,for on-site evaluation of the ischemic effect;a variation of this technique,with intraarterial(instead of intravenous)administration of diluted echo enhancer,can also be applied intraoperatively,to map the embolized territory and to prevent non-target embolization.Initial experience with USelastographic techniques(shear-wave and strain elastography)has shown that they can detect and quantify the improvement of tissue elasticity post-PAE,thus providing new insights into the therapeutic mechanisms of this treatment.With utilization of high-end equipment,experience and standardized imaging protocols,US could be the primary modality for imaging evaluation of PAE.
基金
The authors are grateful to Dr.de Assis AM,Interventional Radiologist,Interventional Radiology Department,Radiology Institute,University of Sao Paulo Medical School,for providing the SWE images and for sharing his valuable experience on USelastography of PAE.