Fig. 45.3  Venous outflow plethysmography shows mild obstruction in the right limb. After tourniquet application there is a severe decrease in outflow

Question 7

What are the expected findings on exercise plethysmography?

A.  Normal calf ejection fraction in the left limb B.  Reduced calf ejection fraction in the right limb C.  Both

D.  Neither

Exercise plethysmography demonstrated a normal left calf ejection fraction. The right calf ejection fraction is severely reduced. The patient was encouraged to continue wearing elastic compression stockings. He will be evaluated again in 1 year. This may be enough time for the deep venous system to develop.

45.1  Commentary

Clinical Presentation

The triad of capillary malformation with port wine nevus, long bone hypertrophy, and lateral varicosity characterizes KTS (Fig. 45.4).1 2 These lesions are frequently of lateral distribution and rarely cross the midline. Typically, one lower extremity is involved, but bilateral presentation or upper extremity involvement is possible. Occasionally, capillary or venous malformations can cause bleeding and cellulitis in patients with poor skin coverage. The same can occur through defects in the mucosa. Pelvic involvement with venous malformation may present with rectal bleeding or hematuria.3 The hallmark of venous malformations in KTS is persistence of embryonic veins. The lateral marginal vein of Servelle has been the most typical finding.4 Another persistent embryonic vein is

Fig. 45.4  Characteristic triad of KTS: port wine stains, lateral varicose veins, and slightly longer extremity

the sciatic vein.5 The deep venous system may be anomalous. It may be hypoplastic, atretic, or much less frequent, non-existent. The deep venous valves may be hypoplastic or absent. [Q1: A]

Evaluation

Diagnostic tests in KTS should focus on the evaluation of the type, extent, and severity of the malformation. The absence of a clinically significant arteriovenous shunt should be confirmed. A thorough physical examination is complemented by color duplex of the venous system. This test can detect anomalies such as atresia, hypoplasia, and aneurysms of the deep veins. In addition, duplex can confirm patency and incompetence of deep, superficial, and perforator veins.

Plain X-rays of the long bones (scanogram) are helpful to measure length of bones. Magnetic resonance imaging can differentiate between muscle, bone, fat, and vascular

tissue. Contrast venography can be performed through multiple injections in the limb. A tourniquet can be used to force contrast into the deep system to visualize it. Venography is frequently the only test that can help estimate the degree of deep venous occlusion and the presence of sufficient collateral circulation to permit excision or ablation of large incompetent superficial embryonic veins.6 [Q5: A, B, C, D]

Strain gauge or air plethysmography has been utilized to compare the limbs of patients with KTS and normal controls. The limbs of patients with KTS are characterized by complex reflux patterns, severe valvular incompetence, calf muscle pump impairment, and venous hypertension.7 [Q6: A] [Q7: C]

Treatment

Absolute indications for treatment in KTS include hemorrhage, infections, acute thromboembolism or refractory venous ulcers. Relative indications include pain, functional impairment, swelling due to chronic venous insufficiency, limb asymmetry or major cosmetic reasons. [Q4: A, B, C, D]

The management is mostly conservative. The mainstay has been compression therapy in the form of elastic garments, non-elasticbandages,and intermittentpneumatic compression. For venous swelling and chronic lymphedema physical therapy using massage treatmentandphysicaldecongestivetherapyhasbeenusedwithgoodsuccess.Thepsychological impact caused by a visible deformity of KTS should not be underestimated. Participation of patients and families in support groups is strongly encouraged.8

Intervention is reserved for selectively symptomatic patients with KTS. A careful evaluationmustprecedeanyintervention.Theextentofmalformationsandpatencyofthedeep system must be assessed. High ligation of the incompetent marginal vein, invagination stripping of long superficial veins and ambulatory phlebectomy through stab wounds are the most commonly used techniques, although endovenous thermal ablation is gaining popularity and can be used in patients who do not have the lateral vein immediately under the skin. Tumescent anesthesia can be used to carefully separate the distance between the skin and the treated vein. [Q2: A, B, C, D]

Lumbar sympathectomy is helpful for occasional severe hyperhidrosis in these patients. The placement of a temporary IVC filter is indicated in patients with a history of pulmonary thromboembolism.

The use of subfascial endoscopic perforator surgery in patients with large incompetent perforating veins and venous ulcers has been useful and some patients benefit from deep venous reconstructions. Limb exsanguination with Esmarque bandage and tourniquet use help to reduce intraoperative blood loss during varicose vein avulsion or SEPS.9

Endovenous therapies have included sclerotherapy and embolotherapy with alcohol, sodium tetradecyl sulfate, and polidocanol. Serial sclerotherapy with alcohol has excellent results in 75–90% of patients with low-flow malformations according to Burrows.10 However, caution should be used in malformations close to peripheral nerves. Foam sclerotherapy with Polidocanol or Sodium Tetradecyl sulfate is being used with success with increasing frequency. 11, 12 [Q3: A, B, C, D]