US Duplex Doppler IVC and Iliac Veins Because duplex US is noted as the first assessment of the lower extremity veins, it can also be used as means to determine patency of the IVC and iliac veins. A good quality examination with normal findings may obviate the need for further imaging. However, in some cases, visualization of the IVC and common iliac veins can be limited in some patients because of obesity or artifacts. Spectral waveforms can aid as an indirect means of assessing patency of the iliac veins or IVC. Evaluation of waveforms in the common femoral veins will show loss of respiratory phase variation and exhibit monophasic physiology with severe iliac vein occlusive disease with a high specificity but low sensitivity [74,75]. Variant 8: Iliocaval or lower extremity disease with severe post-thrombotic changes. Treatment. Anticoagulation The role of anticoagulation is most frequently noted in acute DVT [76]. In chronic DVT, anticoagulation also should have a pivotal role. Many patients with prior chronic DVT are at high risk for thrombosis, and these patients should be given therapeutic anticoagulation [77]. Because of the highly thrombotic environment, most of these patients should be given full dose anticoagulation throughout and immediately after recanalization procedures. Compression Therapy Despite the minimal evidence regarding C2 to C4 disease, there is evidence that compression therapy has value in C5 (preventing ulcer recurrence) and C6 disease (healing ulcers) [15]. Mosti and Partsch [18] demonstrated that 30 to 40 mm Hg inelastic compression is better than elastic bandaging for wound healing. They also showed that for ankle-brachial indices between 0.9 to 0.6, reduced compression to 20 to 30 mm Hg is successful and safe for VLU healing. Velcro inelastic compression was noted to be as good as 3- or 4-layer inelastic bandages. Caution is advised,
Lower Extremity Chronic Venous Disease. US Duplex Doppler IVC and Iliac Veins Because duplex US is noted as the first assessment of the lower extremity veins, it can also be used as means to determine patency of the IVC and iliac veins. A good quality examination with normal findings may obviate the need for further imaging. However, in some cases, visualization of the IVC and common iliac veins can be limited in some patients because of obesity or artifacts. Spectral waveforms can aid as an indirect means of assessing patency of the iliac veins or IVC. Evaluation of waveforms in the common femoral veins will show loss of respiratory phase variation and exhibit monophasic physiology with severe iliac vein occlusive disease with a high specificity but low sensitivity [74,75]. Variant 8: Iliocaval or lower extremity disease with severe post-thrombotic changes. Treatment. Anticoagulation The role of anticoagulation is most frequently noted in acute DVT [76]. In chronic DVT, anticoagulation also should have a pivotal role. Many patients with prior chronic DVT are at high risk for thrombosis, and these patients should be given therapeutic anticoagulation [77]. Because of the highly thrombotic environment, most of these patients should be given full dose anticoagulation throughout and immediately after recanalization procedures. Compression Therapy Despite the minimal evidence regarding C2 to C4 disease, there is evidence that compression therapy has value in C5 (preventing ulcer recurrence) and C6 disease (healing ulcers) [15]. Mosti and Partsch [18] demonstrated that 30 to 40 mm Hg inelastic compression is better than elastic bandaging for wound healing. They also showed that for ankle-brachial indices between 0.9 to 0.6, reduced compression to 20 to 30 mm Hg is successful and safe for VLU healing. Velcro inelastic compression was noted to be as good as 3- or 4-layer inelastic bandages. Caution is advised,