The veins are assessed for patency by demonstrating if they are compressible and free of thrombus. Both legs can be examined in the one sitting but often it is preferable to do them one at a time. For large or swollen legs the probe will have to be pushed quite firmly to assess the deeper veins.Ī comprehensive examination of all the deep and superficial veins of one leg may take up to 30 minutes. If the valve is incompetent blood flow will be seen flowing back down the vein (retrograde flow) after the calf has been squeezed. The sonographer will be required to squeeze the patient’s calf quite regularly to identify areas of valvular incompetence. The deep and superficial veins are assessed with B-mode and Doppler to assess patency and to determine the direction of the blood flow. Gel is applied to the skin and the ultrasound probe is run up and down the leg following the veins. The study is non-invasive and does not involve any needles. This is necessary in order to assess the presence of valvular insufficiency against the effects of gravity. The patient is examined in a standing position or a sitting position with the legs dependant. They should wear loose fitting clothes or be prepared to remove the outer garments of the lower extremity. The patient will need to have the leg being examined exposed from the groin to the foot. PATIENT PREPARATION AND EXAMINATION TECHNIQUE: Varicose veins are strongly associated with family history, gender and pregnancy and occupation. Symptoms of venous incompetence can be dilated tortuous superficial veins, swelling, feelings of heaviness and aching in the leg and in severe cases skin health changes in the lower leg or even ulceration. When the deep vein valves malfunction this results in deep venous reflux, which can be a secondary cause of the superficial varicose veins. When this valvular malfunction occurs in the superficial veins of the leg, the greater saphenous vein and the smaller saphenous vein, these veins became dilated and tortuous and are described as varicose veins. As more valves become damaged the veins come under greater pressure and the veins begin to dilate. When these valves malfunction they allow this retrograde flow within the vein. These valves are designed to prevent gravity assisted retrograde flow (or reverse flow away from the heart and back down the leg) within the veins. One way valves within the veins are situated throughout the deep and superficial veins of the leg. Venous blood is normally directed from the superficial veins into the deep veins with all normal venous flow directed back to the heart via the deep veins. doi:10.1161/ in the legs consist of deep veins lying adjacent to arteries and superficial veins with perforating veins and junctions between the two. The Edinburgh Vein Study of Venous Disorders in the General Population. Chronic Venous Insufficiency: Clinical and Duplex Correlations. Ruckley C, Evans C, Allan P, Lee A, Fowkes F. Chronic Venous Insufficiency and Dystrophic Subcutaneous Calcification. Duplex Ultrasound Evaluation of Patients with Chronic Venous Disease of the Lower Extremities. Duplex Assessment of Venous Reflux and Chronic Venous Insufficiency: The Significance of Deep Venous Reflux. Welch H, Young C, Semegran A, Iafrati M, Mackey W, O'Donnell T. The patient should be able to stand for this procedure. The presence and location of perforators are also documented. Venous duplex imaging may provide information about local valve function to construct an anatomic map of disease in terms of the systems and levels of involvement. The longer the duration of reflux or the greater the reflux time implies more severe disease Reflux time of >0.5 seconds for superficial veins and 1.0 second for deep veins has been used to diganose the presence of reflux 8, although a more refined definition with a variable “cutoff” based on location has been suggested ref The duration of reflux is known as the "reflux time" (replacing the commonly used "valve closure time"): The presence of reflux is determined by the direction of flow because any significant flow toward the feet is suggestive of reflux. Typically the great saphenous vein and the small saphenous vein and their primary tributaries are assessed. Soft tissue swelling from subcutaneous edemaĬonsidered the primary imaging modality of choice. Solid undulating periosteal reaction, often symmetrical Venous hypertension caused by vascular malformations, arteriovenous fistulae, and neuromuscular disorders (rare)įindings are non-specific but most commonly are seen in the leg 5,6: The condition results from venous hypertension which in turn is usually caused by reflux in the superficial venous compartment. Symptoms of chronic venous insufficiency include heaviness, tension, swelling feeling, aching, itching and/or cramps 7.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |