[Ultrasonic diagnosis of complications after bypass operations in lower extremities arteries]

After reconstructive vascular operations the patients need dynamic control and non-invasive monitoring. The purpose of the study was to reveal the potential of duplex scanning (DS) in assessment of bypasses function and diagnosis of postoperative complications. 148 patients after aorto-femoral and femoro-popliteal bypass, including patients with late postoperative complications (shunt thrombosis, stenosis or spurious aneurysm of anastomosis) were examined. Energy colored DS was performed in scans "Toshiba" SSH-140 and "Acuson" Sequoia-512. In ultrasonic diagnosis the vascular graft was imaged as a tube structure with hyperechogenic walls and distinct pulse; it was easy to detect the material of vascular graft. In examination of distal anastomosis the initial portions of efferent arteries were usually imaged distinctly. In satisfactory distal vascular bed, the shunt's blood flow did not differ from normal blood flow. In patients with multifocal lesions the spectrum of shunt's blood flow was similar to main-changed blood flow. Substantial change of blood velocity was revealed in complications (aneurysm or stenosis of anastomosis). Spurious aneurysm was imaged as a hypoechogenic pulsating formation. Thrombotic masses in aneurysm's cavity were distinctly detected at DS, unlike at angiography. In case of anastomosis insufficiency, the suture's disrupted filaments and free branch's ends could be imaged. Stenosis of anastomosis was characterized by visible lumen's stenosis, local thickening and unevenness of wall, spectrum's change and blood velocity increase. In shunt's thrombosis the DS permitted to follow the thrombed graft's path, to reveal the cause of thrombosis and to detect the condition of outflow tract. The authors regard DS as a method of choice in dynamic control for state of bypasses and arteries in patients after reconstructive operations in lower extremities arteries.