tailieunhanh - Peripheral Vascular Ultrasound - part 10

Trong trường hợp này, nó có thể thấy một sự gia tăng đáng kể trong PSV trong sự vắng mặt của một hẹp (Hình 14,11). Tuy nhiên, vận tốc dòng chảy ngay dưới hai mạch máu tiếp hợp với nhau xa nên được tương tự như những hạ lưu một vài cm, đường kính tàu là như nhau | 216 PERIPHERAL VASCULAR ULTRASOUND Figure A Hyperemic flow is often seen in the early postoperative period. B Over time the flow normally assumes a pulsatile flow pattern. large-diametervein ị ft joined toil smeileroui-flow arteryiproducmga natural veiocrty increase. In this situation it is possible to see a significant increase in the PSV in the absen ce ofa stenosis Fig. Howeven flowaeloeésiesjustbelow the distalannstomosisshould pe tímiiarto fhose several centimeters downstream provided epsat eho vessel diamatcristhc HmCiA slgnificsottseoo sis would bpmdicasedifthe selocitres atvdo anastomosis weoefoundto be sobtSanilailySigens . 3-4 times than Sdiin kii ứ ltiaireips ei tant to casnsctldic sin tpponaf c ppies Pid ip prt correctly ss shcOistieloiintVomosit at Hew is not always parallei to rhvi ocscl woils andtdls canlcađ to errors mvpSosieymvarurpmenes. Abnormalsppeasancn l s i Graft stenoses are categorized using a similar method tothatfor gmdrnglower limb ạrtẹnal disease. The PSV across the stenosis is divided by the PSV in s PO rmeS so ni t ps graSt just p ooximal to the stesopr snigi 1 Tha criteria fna foaling Figure Problems in interpreting flow velocities in a vein graft anastomosed to the posterior tibial artery. At point A the PSV in the distal graft is 65 cm s. At point B the PSV in the posterior iOe anastomosis sirs cm SiChisieaittests e t er idouiH eg in dis meter of the posterior tibislartarnisslgsificantl ysmalIerthen that of ther aleitsti Itadintioa natsrtlitciceth ir systolic velr vttos y is inveitels riOSsS to cross-sectivnal spi ani inthisexampis novstrowintis indicated. UhesituatSeItihSphiet tie civoificant sieooris is demonstrate is 01s posterioiOibiai trtery 2smdistal to the anadirt-site byro iorhlisweIicsiag tnha agnificant mcteaaein thsPSV 400emSSiisthisimagt there issomeretsctradefilrngafShonaSiveveosei above theanastomoais