Venous Assessment
Inspection is the most important since it may reveal ulceration,spider veins, skin alteration (atrophie blanche),fungal involvement like interdigital mycosis, acrocyanosis, eczematous lesions, microulcers, stasis dermatitis, flat angiomata, prominent varicose veins, scars from a prior surgical operation, or evidence of previous sclerosant injections. Measuring and photographing lesions is recommended because patients undergoing treatment for varicose and spider veins often forget the original appearance of their legs and feet and may report that preexisting lesions were caused by treatment
Normal veins typically are visibly distended at the foot and ankle and occasionally in the popliteal fossa. For other regions of the leg, visible distension of superficial veins usually implies disease. Translucent skin may allow normal veins to be visible as bluish subdermal reticular pattern, but dilated veins above the ankle usually are evidence of venous pathology.
Discolored skin often is a sign of chronic venous stasis, particularly if it is localized along the medial ankle and the medial aspect of the lower leg. Nonhealing ulcers in this area are most likely due to underlying venous stasis. Skin changes or ulcerations that are localized only to the lateral aspect of the ankle are more likely to be related to prior trauma or to arterial insufficiency than to pure venous insufficiency.
Palpation:
The entire surface of the skin is lightly palpated with the fingertips because dilated veins may be palpable even where they are not readily observed. Palpation helps to locate both normal and abnormal veins. After light palpation to identify superficial vascular abnormalities, deeper palpation helps to elucidate the causes and sources of the superficial problems.
- Palpation begins with the anteromedial surface of the lower limb (the territory of the long saphenous vein), proceeds to the lateral surface (collateral varicose veins of large trunks and nonsaphenous varicose veins), and finally focuses on the posterior surface (territory of the short saphenous vein) of both lower limbs. The location, size, shape, and course of all varicosities are noted, and the diameter of the largest vessel is measured as accurately as possible.
- Palpate distal and proximal arterial pulses. An ankle-brachial index is useful if any suspicion of arterial insufficiency exists.
- The arch of the long saphenous vein may be palpated in some patients without varicose veins, but it is particularly well appreciated in patients with truncal reflux at the saphenofemoral junction. It is best palpated 2 fingerbreadths below the inguinal ligament and just medial to the femoral artery. If reflux is present, a forced coughing maneuver may produce a palpable thrill or sudden expansion at this level.
- The short saphenous vein may be palpable in the popliteal fossa in some slender patients. Other normal superficial veins above the foot are not usually palpable even after prolonged standing.
- Palpation of an area of leg pain or tenderness may reveal a firm, thickened, thrombosed vein. These palpable thrombosed vessels are superficial veins, but an associated deep vein thrombosis may exist in up to 40% of patients with superficial phlebitis. When
- completely thrombosed, the popliteal vein (a continuation of the femoral vein as it passes behind the knee and into the calf) may sometimes be palpated in the popliteal fossa, and the same is true of the common femoral vein at the groin. Palpation for deep thrombosis is not reliable because the vast majority of cases of deep vein thrombosis do not produce any palpable abnormality.
- Varices of recent onset are easily distinguished from chronic varices by palpation. Newly dilated vessels sit on the surface of the muscle or bone; chronic varices erode into underlying muscle or bone, creating deep boggy or spongy pockets in the calf muscle and deep palpable bony notches, especially over the anterior tibia.
- Palpation often reveals fascial defects in the calf along the course of an abnormal vein at sites where superficial tributaries emerge through openings in the superficial fascia. Incompetent perforating veins may connect the superficial and deep venous systems though these fascial defects, but the finding is neither sensitive nor specific for perforator incompetence.
Percussion:
Venous percussion is useful to determine whether 2 venous segments are directly interconnected. Percussion can be used to trace the course of veins already detected on palpation, to discover varicose veins that could not be palpated, and to assess the relationships between the various varicose vein networks.
With the patient in a standing position, a vein segment is percussed at one position while an examining hand feels for a pulse wave at another position. The propagation of a palpable pulse wave demonstrates a patent superficial venous segment with open or incompetent valves connecting the 2 positions. The examination findings can be misleading because prolonged standing causes even a normal vein to become distended. If valves have floated open, a pulse wave may be propagated even in a normal vein. The technique is most valuable when a bulging venous cluster in the lower leg has no obvious connection with veins in the upper thigh, yet a palpable pulse wave demonstrates the existence of an unseen connection.
Percussion can be used to elucidate the course of any significant superficial vein. With the patient standing, the lowest portion of the vein is percussed while the opposite hand searches above for a percussion wave. The procedure is repeated along the entire course of the vein and then along every identifiable superficial vein until a clear anatomic picture has been elucidated.
Perthes maneuver:
The Perthes maneuver is a traditional technique intended to distinguish antegrade flow from retrograde flow in superficial varices. Antegrade flow in a variceal system indicates that the system is a bypass pathway around deep venous obstruction. This is critically important because, if deep veins are not patent, superficial varices are an important pathway for venous return and must not be sclerosed or surgically removed.
- To perform the Perthes maneuver, a Penrose tourniquet is placed over the proximal part of the varicose leg in such a way as to compress superficial varicose veins but not the deep veins. The patient walks or performs toe-stands to activate the calf muscle pump. The calf muscle pump normally causes varicose veins to be emptied, but if deep system obstruction exists, then the varicose veins paradoxically become more congested.
- If the result of the Perthes maneuver is positive (ie, distal varices have become engorged), then the patient is placed supine with the tourniquet in place and the leg elevated (Linton test). If varices distal to the tourniquet do not drain after a few seconds, deep venous obstruction must be suspected. These maneuvers are not consistently reliable and are of primarily historical interest.
- Trendelenburg test: The Trendelenburg test can often be used to distinguish patients with superficial venous reflux from those with incompetent deep venous valves.
- The leg is elevated until the congested superficial veins have all collapsed. An examining hand is used to occlude a varicose vein just below the saphenofemoral junction or at another point of suspected reflux from the deep system into the superficial varicosity. The patient stands with the occlusion still in place.
- If the distal varicosity remains empty or fills very slowly, the principal entry point of high pressure into the superficial system has been identified. Rapid filling despite manual occlusion of the suspected high point of reflux means that some other reflux pathway is involved.
Doppler auscultation: see there
Lab Studies:
- Laboratory tests are not useful for patients with varicose veins.
Other Tests:
- Physiologic tests of venous function are important adjuncts to anatomic imaging of venous disease. The physiologic parameters most often measured are the venous refilling time (VRT), the maximum venous outflow (MVO), and the calf muscle pump ejection fraction (MPEF).
- The venous refilling time is the time necessary for the lower leg to become suffused with blood after the calf muscle pump has emptied the lower leg as thoroughly as possible.
- When perfectly healthy patients are in a sitting position, venous refilling of the lower leg occurs only through arterial inflow and requires at least 2 minutes.
- In patients with mild and asymptomatic venous insufficiency, some venous refilling occurs by means of reflux across leaky valves. These asymptomatic patients have a VRT that is 40-120 seconds.
- In patients with significant venous insufficiency, venous refilling occurs through high-volume reflux and is fairly rapid. These patients have an abnormally fast VRT of 20-40 seconds, reflecting retrograde venous flow through failed valves in superficial and/or perforating veins. This degree of reflux may or may not be associated with the typical symptoms of venous insufficiency. Such patients often report nocturnal leg cramps, restless legs, leg soreness, burning leg pain, and premature leg fatigue.
- A venous refilling time of less than 20 seconds is markedly abnormal and is due to high volumes of retrograde venous flow. High-volume reflux may occur via the superficial veins, the large perforators, or the deep veins. This degree of reflux is nearly always symptomatic. If the refilling time is shorter than 10 seconds, venous ulcerations are so common as to be considered virtually inevitable.
- The MVO measurement is used to detect obstruction to venous outflow from the lower leg, regardless of cause. It is a measure of the speed with which blood can flow out of a maximally congested lower leg when an occluding thigh tourniquet is suddenly removed.
- The advantage of MVO testing is that it is a functional test rather than an anatomic one, and it is sensitive to significant intrinsic or extrinsic venous obstruction from any cause at almost any level. It can detect obstructing thrombus in the calf veins, the iliac veins, and the vena cava, where ultrasonography and venography are insensitive. It also detects venous obstruction due to extravascular hematomas, tumors, and other extrinsic disease processes.
- The disadvantage of the test is that it is sensitive only for significant venous obstruction and does not detect partially obstructing thrombus. It is not useful for detection of venous insufficiency states. A normal MVO absolutely does not rule out deep vein thrombosis.
- The MPEF test is used to detect failure of the calf muscle pump to expel blood from the lower leg.
- MPEF results are highly repeatable but require a skilled operator to obtain clean meaningful tracings. The patient is asked to perform 10-20 tiptoes or dorsiflexions at the ankle, and the change in some physical parameter that reflects calf blood volume is recorded as the calf muscle is pumped.
- In patients without varicose veins, 10-20 tiptoes or ankle dorsiflexions cause the venous capacitance circuit of the calf to be emptied.
- In patients with muscle pump failure, severe proximal obstruction, or severe deep vein insufficiency, tiptoes or ankle dorsiflexions have little or no effect on the amount of blood remaining within the calf.