Endoluminal vascular and nonvascular sonography: past, present, and future

Almost since the beginnings of medical sonography, investigators have attempted to place miniature sonographic transducers into vascular and nonvascular lumina to image abnormalities. The primary goal of intravascular imaging has been the evaluation of atherosclerotic lesions and the monitoring of interventional therapies in peripheral and coronary arteries. Endoluminal catheter-based sonography has also been used for the evaluation of the genitourinary and gastrointestinal tracts as well as the bronchotracheal tree to image a variety of abnormalities. Intravascular sonography has been widely investigated, and efficacy has been established in some areas. Preliminary reports have shown that endoluminal sonography has the potential to successfully evaluate anatomic and pathologic structures in a variety of nonvascular lumina.