Introduction
Introduction
What are varicose veins?
The text book definition of varicose veins is that they are tortuous, dilated, superficial veins. This just means that they are lumpy visible veins in the leg.
What do they look like?
Varicose veins might be blue or purple in colour and appear lumpy or bulging veins in the leg. Varicose veins are actually relatively common in the adult population. The problem with varicose veins occurs if they cause symptoms. The symptoms or problems can include pain on standing or sitting, skin changes, ulceration.
What is the normal system of veins in the leg?
Each leg has two systems of veins, the deep veins which run up the leg in the muscles and the superficial veins which run under the skin in the fat between the skin and the muscles. The two systems are joined at various locations. The normal direction of blood flow is from superficial to deep and from deep out of the leg back to the heart.
The deep veins accompany the arteries in the leg. The superficial veins join together into two main trunks. These trunks are the Saphenous veins - there are two. One is called the Long (sometimes called Great) Saphenous vein and the Short Saphenous Vein.
The long saphenous vein runs up the inside of the leg from the inside of the ankle to the groin. At the groin it dives deep and joins the deep veins at the Sapheno-femoral junction.
The Short saphenous vein run from behind the calf where the achilles tendon area is to behind the knee joint. Here is dives deep into the muscle layers and joins the deep veins at the Sapheno-popliteal junction.
How does the venous (vein) system normally work?
The venous system's job is to take blood from the leg and send it back to the heart. The blood in the veins needs to be pushed along. This is done by the muscles of the calf squeezing the veins which run along in them every time the muscles contract.
The blood is normally prevented from returning back down the leg in the wrong direction by a system of valves. These valves allow blood to flow in the correct direction, but prevent blood from flowing in the reverse direction under the force of gravity.
Lack of proper function of the calf muscle pump or lack of proper function of the valves will lead to problems in the venous system.
What types of visible veins are there in the leg?
1) Truncal veins
These are the Long of Short Saphenous veins or major tributaries. These are usually not seen as they are slightly deeper in the layer of fat under the skin. They can be seen if there is very little subcutaneous fat in a very thin person.
2) Reticular veins
Dilated tortuous subcutaneous veins which are not the main Long or Short Saphenous veins. These are feeder veins which drain into the truncal veins (Long/ Short Saphenous veins) or directly into the deep veins via perforating branches.
3) Telangiectasia
Intra-dermal venules (<1mm) . These are also known as spider veins, star bursts, thread veins, matted veins). Telangiectasia or spider veins exist in the skin itself. They do not cause problems in themselves but may well exist in a leg together with reticular or truncal veins.
What is venous insufficiency?
Venous insufficiency is where the normal functioning of the venous system breaks down. We talked about how valves function in the veins to prevent blood from refluxing in the reverse direction. If these valves become faulty then the blood refluxes in the reverse direction under the force of gravity - incompetent veins. As valves are not functioning, the pressure of the blood in the veins increases. This is called venous hypertension.
The increased pressure (venous hypertension) in refluxing veins causes fluid to leak out the veins into the spaces between the surrounding cells. This causes swelling - called oedema.
Cells can also leak out of the veins under the higher pressure. These cells break down in the spaces between the surrounding cells and causes pigmentation of the skin as well as inflammation. The inflammation can cause itching and damage to the skin -called lipodermatosclerosis and also venous eczema.
Can varicose veins be normal?
Yes, for sure! Visible varicose veins in themselves do not mean that you have a problem. If however you have visible varicose veins and venous insufficiency and symptoms or skin changes then you may need to consider treatment.
Aetiology / causes
We cannot say with any certainly what has caused varicose veins in an individual person. However, certain associations are apparent. Varicose veins do certainly seem to run in families, you're more likely to have them if you parents or siblings have them. Varicose veins are more common in women after pregnancy. Our group performed a study called a meta-analysis which reported on this finding (1).
What does venous skin disease look like?
These complications of venous insufficiency are described in the following sections. However, it may be helpful to share some relevant picture.
Differential diagnosis
It is possible to confuse the leg swelling associated with varicose veins and venous insufficiency with other causes of leg swelling including heart failure, lymphoedema and lipodema (see related topic on leg swelling).
Venous eczema can be confused with eczema or inflammation of the skin for any other reason.
Venous insufficiency and the symptoms of venous insufficiency can be confused with the cosmetic appearance of varicosities or reticular veins and thread veins.
Diagnostic approach
Symptom history and medical examination
The diagnosis of venous insufficiency begins with the symptoms you are experiencing. If the symptoms fit with symptomatic varicose veins then further consideration is warranted.
On examination of the legs, there may be visible varicose veins or the venous skin changes described in this topic.
Previously other traditional clinical tests for sites of reflux Tourniquet and Trendelenberg’s tests) were found to be unreliable (2)
Hand held Doppler test
If further investigation is needed, then the hand held doppler test can be done. This helps by establishing if reflux exists at the sapheno-femoral or sapheno-popliteal junctions.
An early study evaluated hand held continuous wave Doppler assessment with Duplex assessment in assessment of primary varicose veins. They reported an accuracy for the hand held Doppler of 73% at the sapheno-femoral junction (SFJ), 77% at the sapheno-popliteal junction (SPJ) and 51% for thigh perforators. Thus, with the hand held Doppler alone, 24% of sites of reflux would be missed (3.
Duplex ultrasound scanning
More detailed mapping of the pathways of reflux is done by Duplex Ultrasound scanning. Here a practitioner scans the veins of the legs while the patient is standing up. Brisk calf compressions are done to push blood up the leg (simulating calf muscle pump action). The practitioner 'listens' for a signal indicating the blood is refluxing in the reverse direction. Refluxing blood in turn suggests that the valves are malfunctioning.
Duplex scanning includes B mode scanning, Colour Doppler and Spectral Doppler testing. The B mode appearance of a Long Saphenous Vein is shown below in cross section. The vein is the black circle in the upper middle part of the display.
Colour Doppler Scanning helps identify veins and arteries as the moving blood shows up as a colour code on the screen. A Colour Doppler image of a perforating vein is show below.
Spectral Doppler scanning allows us to measure accurately the degree of reflux in veins. A typical readout of a refluxing vein is shown below. The negative deflection in the centre of the screen is. blood moving in the upward direction in response to compression of the calf. The prolonged upwards deflection in the second half of the screen is blood refluxing in the reverse direction under the force of gravity. This indicates that the valves are faulty.
A small case control study demonstrated that following release of calf compression, retrograde flow of >0.5 seconds was likely to be pathological (4). A similar study using pneumatic calf compression which looked at many more vein segments concluded that for the sapheno-popliteal junction a cut off value of >1 second should be used, >0.5 seconds should be used for the superficial and deep calf veins and >0.35 seconds used for the perforating veins (5).
Thus reflux in veins should be considered is the reflux time is over 0.5 seconds, 2 seconds can be considered prominent reflux.
Epidemiology
The famous Framingham study found that the 2-year incidence of varicose veins was 39.4/1000 for men and 51.9/1000 for women (6).
Edinburgh study of people aged 18 to 64 y found prevalence of trunk varices to be 40% in men and 32% in women. Over 80 % had had reticular varicosities or telangiectasia. (7)
