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PART 4 — PERIPHERAL VENOUS
venography is uncommon but is still performed spo- radically. Computed tomography venography (CTV) may be used to define the status of the iliac veins. CTV may be done in conjunction with computed to- mography being performed to detect PE. Lastly, mag- netic resonance venography (MRV) is also performed to detect DVT. This modality appears to be most use- ful when imaging veins above the inguinal ligament.
TREATMENT
At present, the primary treatment of acute lower ex- tremity DVT is anticoagulation.24 Heparin and war- farin are used in varying degrees to achieve initial
SUMMARY
levels of anticoagulation. After a period of 4 to 5 days, most patients remain on warfarin for several months. In some patients, depending on the level of disease and the patient’s condition, the physician may also choose to treat DVT with low-molecular weight heparin. Oral anticoagulation medications will be available in the future. Other treatment methods include gradient elastic stockings, which may help to reduce lower extremity symptoms and decrease the risk of postthrombotic syndrome. Thrombolytic agents and thrombectomies (either catheter-based or surgical) may also be used to rapidly dissolve the thrombus or physically remove it. These techniques are often limited to the larger veins of the iliofemoral region.
Imaging of the veins of the leg is a challenging task. However, by paying attention to sound protocols and gaining clinical experience under the supervision of an ex- perienced mentor, one can perform accurate venous duplex examinations that will provide doctors with the information needed to safely manage their patients.
Critical Thinking Questions
1. When reviewing the relevant history of a patient, what three areas should be of the greatest concern?
2. Explain why both transverse and longitudinal imaging is used for venous DVT examinations.
3. Ultrasound is a noninvasive technique. However, venous ultrasound can have two associated negative outcomes. What are these and how can the risks be minimized?
4. What are three aspects of an acute versus a chronic thrombus that can be compared and contrasted?
REFERENCES
1. Strandness DE Jr. Diagnostic approaches for detecting deep vein thrombosis. Am J Card Imaging. 1994;8(1):13–17.
2. Meissner MH, Moneta G, Byrnand K, et al. The hemodynamics and diagnosis of venous disease. J Vasc Surg. 2007;46(suppl S):4S–24S
3. Oliver MA. Duplex scanning in the management of lower extremity DVT. Vasc Ultrasound Today. 2005;10:181–196.
4. Oliver MA. Incidental findings during lower extremity venous duplex examination. Vasc Ultrasound Today. 2008;13:77–96.
5. Hollinshead WH. Textbook of Anatomy. 3rd ed. New York, NY: Harper and Row; 1974:75.
6. Kadir S. Diagnostic Angiography. Philadelphia, PA: W.B. Saunders; 1986:541.