Duplex ultrasound

Endoleaks are a major concern for those engaged in EVAR (Table 3, Fig. 4). This phenomenon describes the continuation of blood flow into the extragraft portion of the aneurysm (20). Endoleaks are related to the graft itself or other factors such as the presence of large patent lumbar arteries (21). The presence of an endoleak increases the chance of rupture. Diagnostic imaging plays an important role in the detection of endoleaks intraprocedural angiograms, surveillance CT scans, or duplex ultrasounds. 

The recommended surveillance routine is for a CT scan at I, 6, and 12 months and annually thereafter. If an endoleak is detected, the frequency of the scans increases to every six months until resolution of the endoleak is detected. Investigators have compared duplex ultrasound with CT scan for surveillance and found that CT scan is superior for endoleak detection (32). Since endoleaks are an important complication with therapeutic implications, CT scans should be used rather than duplex examination for repair surveillance. 

Raman KG, Missig-Carroll N, Richardson X etal, Color-flow duplex ultrasound scan versus computed tomographic scan in the surveillance of endovascular aneurysm repair, J Vase Surg 2003 38(4) 645-651. 

Moneta, G.L. Taylor, D.C. Helton, W.S. Mulholland, M.W. Strandness, D.E. Duplex ultrasound measurement of postprandial intestinal blood flow Effect of meal composition. Gastroenterology 1988, 95 (5), 1294—1301. 

All six surgical events were successfully treated with rhAT, as shown by the absence of clinical evidence of thrombosis for these patients that all had an history of thromboembolism. In two patients, where initial pre-and post-treatment levels were available, there was a 1.69 and 1.66% per U per kg increase, which is similar to the 1.39 and 2.05% per U per kg reported for hpAT. There was no clinical evidence of thrombosis or bleeding, and no adverse events related to the drug were reported. Four of the six surgical events were fol-lowed-up by vascular duplex ultrasound of the lower extremities, with no clinical evidence of acute thrombosis (Table 11.4). Four of the five patients, who receive multiple doses of rhAT, were also screened for antibody formation against rhAT several weeks postoperatively. None of the patients developed detectable antibodies to the rhAT. 

The primary study end-point was incidence of DVT and other thromboembolic events assessed clinically and by both locally and centrally assessed ultrasonography. The duplex-ultrasounds of the lower extremities were used to confirm or exclude the occurrence of DVT. These procedures were performed and interpreted by qualified specialists within the same hospi-tal/institution on a real-time basis for the timely and appropriate chnical care of the patient Furthermore, duplex ultrasound studies were videotaped for a subsequent standardized bhnded interpretation by a quahfied, independent laboratory that provided an unbiased evaluation of the incidence of DVT. ThromboemboHc events other than DVT that occurred during the study period were assessed, and the investigator estabhshed the clinical relationship of the event to treatment with rhAT. Secondary end-points were safety, adverse events and immunogenicity. 

Nederkoorn, P.J., Y. van der Graaf, and M.G. Hunink, Duplex ultrasound ami magnetic resonance angiography compared with digital subtraction angiography in carotid artery stenosis a systematic review. Stroke, 2003. 34(5) p. 1324-32. 

Parent FN, Meier GH, Godziachvili V et al (2002) The incidence and natural history of type 1 and II endoleak a 5-year follow-up assessment with color duplex ultrasound scan. J Vase Surg 35 474-81... 

Wolf YG, Johnson BL, Hill BB, et al (2000) Duplex ultrasound scanning versus computed tomographic angiography for post-operative evaluation of endovascular abdominal aortic aneurysm repair. J Vase Surg 32 1142-8... 

Pages, S, Favre JP, Cerisier A, et al (2001) Comparison of color duplex ultrasound and computed tomography scan for surveillance after aortic endografting. Ann Vase Surg 15 155-162... 

Fig. 5.7. Transvaginal ultrasound of leiomyoma. Transvaginal color-coded duplex ultrasound demonstrates the perifibroid plexus vessels surrounding the leiomyoma...

Colour duplex ultrasound scanning is currently the technique of choice in order to assess the venous system of the lower limb. This technique combines ultrasound imaging with pulsated Doppler ultrasound, and provides detailed anatomic information of the superficial, deep, and perforating venous systems. It can identify specific veins in which blood reflux occurs, or obstructions which may be contributing to venous hypertension. 

Results of duplex and color Doppler sonography in the neck and arms are useful to demonstrate the presence or absence of venous flow,but overlying bone and lung severely hamper examination of mediastinal veins. The SVC can also be evaluated with transesophageal Doppler US, but the modality has a small field of view and is to some degree invasive and time-consuming (SvENSSON et al. 1991). Examination of the iliac veins and IVC is easier with duplex ultrasound, including demonstration of the hepatic and renal veins. 

Amin Z, Patel U, Friedman EP et al (1993) Colour Doppler and duplex ultrasound assessment of Peyronie s disease in impotent men. Br J Radiol 66 398-402... 

Aversa A, Proietti M, Bruzziches R et al (2006) The penile vasculature in systemic sclerosis A duplex ultrasound study. J Sex Med 3 554-558... 

Darvall, K.A., Bate, G.R., Adam, D.J., Silverman, S.H., Bradbury, A.W., 2011. Duplex ultrasound outcomes following ultrasound-guided foam sclerotherapy of symptomatic recurrent great saphenous varicose veins. European Journal of Vascular and Endovascular Surgery 42,107-114. 

Auscultation of the groin classically reveals a (new) continuous bruit after sheath removal, and in most cases a concomitant hematoma and/or pseudoaneurysm can be found. The clinical diagnosis must be confirmed by duplex ultrasonography, which will show a triad of typical signs (1) a colorful speckled mass at the level of the puncture site, (2) an increased venous flow with a lack of respiratory variation and a pulsatile arterial component in the affected vein, and (3) decreased arterial flow distal to the suspected fistula. As for pseudoaneurysms, an arteriovenous fistula can also be detected by more sophisticated imaging tools like MR-, CT- and catheter angiography, but the standard imaging tool is still duplex-ultrasound. 

Duplex ultrasound is essential to document the permanent occlusion of truncal veins treated with EVTA [11-13]. A successful procedure will result in non-thrombotic circumferential vein wall injury from the highest level of the incompetent segment and through its treated course on early evaluation. On late follow-up the vein segment will ideally be obliterated and impossible to find or at least will be significantly smaller in cross section than prior to treatment and will have no flow throughout the treated segment. 

Khilnani NM,Min RJ (2003) Duplex ultrasound for superficial venous insufficiency. Tech Vase Interv Radiol6 lll-115... 

Min RJ, Khilnani NM, Golia P (2003) Duplex ultrasound of lower extremity venous insufficiency. J Vase Interv Radioll4 1233-1241... 

Pichot O, Kabnick LS, Creton D, Mercahant RF, SchuIIer-Petroviae S, Chandler JG (2004) Duplex ultrasound scan findings two years after great saphenous vein radiofrequency obliteration. J Vase Surg 39(1) 189-195... 

Training in Duplex Ultrasound, Catheter Placement and Cannulation... 

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