How Do Perforators Contribute to Varicose Veins?

In addition to saphenofemoral reflux and valve incompetence causing symptomatic venous reflux disease, there are several sites along the greater saphenous vein and lesser saphenous vein where there is potential for branch varicosities and communication with the deep veins of the lower extremities. These include the perforator veins. Perforator veins allow communication between the superficial venous system and deep venous system of the legs. Superficial veins include the great saphenous vein and its branches and the lesser or short saphenous vein and its branches. The deep veins of the legs include the common femoral vein, superficial femoral vein, popliteal vein, tibial vein and peroneal veins, among others. Notice that the superficial femoral vein is NOT a superficial vein because of the word femoral, as all femoral veins are deep veins!

So what does the "perforator" terminology mean? It means that the vessel "perforates" the aponeurosis of the muscle, giving it the name.  The aponeurosis is fascial tissue that invests or envelops muscle groups and binds these muscle groups to other muscle groups or to bone.

According to Dr. Alberto Caggiati (Rome, Italy), perforator veins were not identified nor described by the 'fathers of vascular anatomy and physiology' in the 16th and 17th centuries. Perforator veins were first reported in the Anatomische Tafeln zur Beforderung der Kenntniss des menschichen Korpers (Weimar, 1794-1803), the main work of the German anatomist, Justus Christian Von Loder (1753-1832). 

The superficial veins communicate with the deep veins via perforator veins. If you imagine the two legs of the letter "H" , the perforator is the connection between the two legs of the letter "H".

There are valves within these perforator veins which can also become incompetent and cause branch vein varicosities throughout the lower extremities - at the level of the thighs, knees, lower legs, ankles and feet.

Perforator veins typically have one to three valves. These are bicuspid valves. that is with two valve cusps. This is unlike the tricuspid aortic heart valve (3 cusps, looking like the 'Mercedes Benz' insignia). These bicuspid valves of the perforator veins are oriented to allow blood to go in one direction, from the superficial veins to the deep veins. The unidirectional blood flow in these perforator veins is also maintained by the oblique course of the perforator veins through the muscle and aponeurosis (see above for definitions). As shown in the cartoon below (taken from Jean Francois Uhl, MD) that perforator veins are direct (with an oblique course) or indirect, i.e. through an arborizing network of veins. The latter gives an added degree of complexity to an already complex network of veins that result in perforator based venous reflux disease.

The average number of perforator veins per extremity is highly variable and reported in the literature to be as many as 155!  Obviously, not all of these are clinically important, but some can cause significant morbidity to the patient. They are thought to play a fundamental role in the development of varicose veins in the lower extremties.

A recently published study from Zagreb, Croatia (Croat med J 2005; vol 46: page 245-251) showed that deteriorating venous insufficiency of the great saphenous vein correlates with the number of incompetent perforator veins per leg as well as the diameter of the perforator veins.  This implies that the presence of perforator venous reflux represents a significant factor in the development of venous reflux disease in the great saphenous vein. Other conclusions also derived from this seminal study are that with the deterioration of CEAP grade, a scoring system for venous disease, there is an increased capacity for blood volume be expelled down a pressure gradient through both dilated low-resistance incompetent perforators and the incompetent greater saphenous vein. As such, if surgery is limited to the great saphenous system alone, surgery would be insufficient. Perforator surgery should be added when they have obvious perforator venous reflux disease.

Why is perforator surgery important? It has been estimated that in patients who develop chronic venous insufficiency, 4% will progress to develop venous stasis ulcers. That is a high number, signifying that 1 in 25 people who have chronic venous insufficiency will develop these venous stasis ulcers.

As well, a study published in the European Journal of Vascular and Endovascular Surgery (volume 21: page 458-460) demonstrated that patients with recurrent varicose veins have both a higher prevalence and a greater number of incompetent perforating veins than patients with primary varicose veins. As such, the importance of addressing and treating perforator venous reflux disease cannot be underscored.

Treatable superficial venous reflux disease is associated wtih perforator venous reflux disease in approximately 77% of patients with venous stasis ulcers and 57% of patients with trophic changes in the legs. The conclusion from this data is that patients with venous stasis ulcers and trophic changes with combined superficial venous reflux disease and perforator venous reflux disease benefit from treatment of perforator veins.

The distribution of perforator veins increases in density and one approaches the ankle - they occur in a ratio of 8:1, with 8 times more perforator veins in the lower leg, ankle and foot than in the thigh.  More important that the sheer number of these perforator veins is the number of incompetent perforator veins .  When they are incompetent, perforator veins reach diameters of 5 mm or more and can have large volume flow, feeding an array of varicose veins above the fascial layer of the muscle.

The gaiter areas are the areas where skin changes and venous stasis ulcers are most likely to occur - these areas are where the most prominent perforator veins are likely to be found. perforator vein incompetence in these gaiter areas have been shown to increase ambulatory venous pressures above 100 mm Hg (venous hypertension), a phenomenon which has also been referred to "ankle blow-out" syndrome in the gaiter areas. The combination of incompetent perforator veins and resultant venous hypertension over time causes damage to capillaries in the skin and nd subcutaneous capillaries, allowing protein rich fluid and red blood cells to escape into the subcutaneous tissue around the ankle. The effect is that the subcutaneous tissue becomes fibrotic and skin pigmentation results from hemosiderin deposition. 

The clinically important perforator veins are in the thigh (Dodd's and along Hunter's canal), calf (soleus and gastrocnemius types), medial leg below knee (Boyd's), lateral (outer) leg (peroneal) and Cockett's. The Cockett's type is the most recognized and occurs within 20 cm of the ankle. The tenet of the constancy of Cockett's perforating vessels does not hold against anatomical studies. They perforate the fascia at various levels as their relationship to Linton's line also vary. They occur within a "lane" of 3 cm along the line previously described by Linton. the first set occurs within 6-10 cm of the ankle; another set of Cockett's perforators occur at 13.5 cm to 15 cm of the ankle; a third set of Cockett's perforators occur from 18 cm to 20 cm of the ankle; the fourth and final set of Cockett's perforators occurs between 24 and 25 cm of the ankle along Linton's "lane". An experienced phlebologist can locate these important perforators and deal with them in a manner to heal venous stasis ulcers and also to treat symptomatic varicosities arising from these refluxing perforator veins.

image taken from medcyclopedia.com on January 11, 2009 (see above)

image of the named veins of the legs, on the left is the anterior aspect of the thighs and legs; the right image is the posterior aspect of the thigh and leg - taken from alaskaveinclinic.com on November 14, 2009 (image changed on this date from prior image in January 2009).

image of marked Cockett's perforator veins for surgical ligation taken from circulationforum.com on January 11, 2009 (see above)

There are also recognized perforaor veins of the foot (medial and anterior and lateral) that can cause significant morbidity when they are incompetent. Peroneal perforator veins are also the 'lateral calf perforators' and are found 5-7 cm (Bassi's veins) and 12-14 cm from the lateral ankle. The peroneal perforators connect the lesser saphenous veins with peroneal veins. 

image taken from phlebologia.com on January 11, 2009

So, how does one get varicose veins after the VNUS Closure procedure? This is a very good question and as the carton image below shows, perforator veins below the ablation segment of the great saphenous vein using VNUS Closure contribute connections to the superficial system of veins and thus give rise to surface varicosities that become inflamed. Clinically, patients present with phlebitis and all of the symptoms associated with inflamed cords of varicose veins: aching, pain, heaviness, tiredness, fatigue, itching, burning, cramping, throbbing, restless legs and swelling (see image below):

image taken from dssurgery.com on November 14, 2009 (image changed on this date from prior image)

In the past, surgery designed to divide the perforating veins, such as Cockett and Linton procedures, were associated with considerable morbidity. The recently developed technique of subfascial endoscopic perforator surgery (SEPS) has allowed perforating veins to be divided effectively but with considerable incisions and down time. As importantly, utilization of minimally invasive techniques that have been developed by Dr. Karamanoukian using expertise he has gained as a cardiac surgeon have revolutionized these techniques into smaller incisions that allow optimal wound healing with minimal morbidity.

There is hope! New technology using radiofrequency ablation allows for obliteration of these perforators under local anesthesia in an ambulatory office setting. New VNUS catheters allow for obliteration of these perforators in the mid calf or thigh. These ablative technologies are used selectively at the Vein Treatment Center to achieve the desired effect in healing venous stasis ulcers and treat recalcitrant varicosities that are not responsive to microphlebectomy or VNUS Closure.

Patients with venous ulcers in the legs may well have perforator reflux and can be screened by clinical examination at the time of consultation using the Brodey-Trendelenberg test and the Bracey variation of this test. They are confirmed by the presence of fascial defects on examination and verified by an ultrasound and duplex venous study. We have clinical expertise at the Vein Treatment Center to diagnose and treat perforator veins and reflux originating from perforator veins. Minimally invasive techniques can accomplish ligation of these perforators to help heal stasis ulcers and get you back to your routine.

The surgeons at the Vein Treatment Center have the technology and equipment to diagnose and treat perforator reflux disease. To schedule an ultrasound screening examination, contact us at (716) 839-3638.

For more information about varicose veins, spider veins, venous reflux and treatment options such as the closure procedure or guided sclero, contact Dr. Karamanoukian at the Vein Treatment Center, a National Center of Excellence for Vein Disorders by email or by phone at (716) 839-3638.