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Looking at the bibliography of the venous sole of the foot (Lejars), the authors point out the opposite convictions concerning this structure. For some ones, it doesn't exist, but fort the others, it is a very important network of tiny veins, such as it was described by Lejars himself. However, all this studies, are made upon cadavers, injected or not, and must be compared with results from living people by the mean of angiography, non invasive Vascular Assessment, or RMN, which take in account vasomotricity.

The development of new direct methods for treatment of deep venous insufficiency requires improvement of the ultrasonographic investigation of valve function. The combination of imaging and pulsed Doppler provides more accurate diagnoses and can be used to establish deep venous hemodynamic cartography. Four essential rules must then be followed: an examination in standing position, proximal decompression tests, examination by one third segments and by thirds of each segment, analysis of the forgotten veins of the leg (soleus, gemellar) and thigh (profunda femoris, quadriceps, posterior ischiatic anastomotic flow) and of the deep muscular anastomoses. The hemodynamic direction of each feature of the venous map is then noted. This investigation enables the following in the context of disease: the diagnosis of deep venous pain affecting an apparently non-varicose area; precise monitoring of the post-thrombotic status of a deep vein, avoiding diagnostic errors related to a painful repermeation syndrome; preselection of cases of deep venous insufficiency suitable for anatomical surgical treatment or a hemodynamic technique (CHIVP) as indicated by the deep hemodynamic cartography which this investigation makes possible.

Plethysmographic techniques based on the variation of a parameter linked to venous stasis, have permitted an approach to venous hemodynamics. The use of a new technique of air-plethysmography, which cold be quantified in volume variation, and permitting to study the progression of the venous stasis from a static as well as a dynamic standpoint, enable us to better assess the overall venous function. The first results obtained in healthy patients, are presented and the advantages of this new technique are discussed.

We are far from being thoroughly acquainted with lympho-venous pathology, despite minute research in this field. The only physiological lympho-venous communications are macroscopic. The existence of microscopic communications has been proved in animals, but it seems that anastomoses become pathologically normal whenever the lymph flow is at all checked. It should be particularly noted that the vasculo-tissular equilibrium is precariously dependent on the physiological condition. The slightest disturbance can upset this balance, resulting in the formation of lympho-venous anastomoses, which attempt to set up a balance difficult to maintain.

A study of 190 female patients was carried out at the level of the solar ring, the crural arch, the left ilio-caval junction and the vena cava ring of the diaphragm, in order to determine whether these represent, per se, critical areas, which may cause compression and hinder the venous return as a result of the narrowing and the poor distention of their structures. Sonotomography alone or associated with the pulsed Doppler were selected for this study. The action of the various components (bone, muscle, tendon, vessels and nodes) on the venous system is each region, was analyzed. The overall results have demonstrated two types of compression: a) intermittent, b) permanent. The former is considered as a hemokinetic mechanism, especially at the level of the solar arch and the vena cava ring of the diaphragm. They represent a major element of the pump and the vis-a front respectively. The permanent compression was considered as pathological, and could be related to a venous displacement occurring as an adaptation mechanism to the extrinsic compression. The data obtained in all four regions, have demonstrated that their various components are in a precarious balance, but they do not constitute a true obstacle to the venous return, even if in some postures or respiratory movements they may cause an intermittent venous compression.

Pelvic veins and lower extremities veins form a functional unit resulting in the interaction of their pathology. The intrapelvic venous system consists of two independent networks, under physiological conditions: the parietal and the visceral networks. The main collectors are the internal iliac veins, the ovarian superior rectal veins. The original venous plexi, located in the sub-peritoneal pelvic connective tissue, remain open because of the adhesion of their wall to the parietal pelvic fascia. The parietal venous network, abundant and supplied with valves, includes the retro-public and sacral plexi. The usual venous drainage is encouraged by abundant anastomoses, the decrease or even the absence of valves and the abdominal pressure. When this pressure increases, especially during walking, this encourages pelvic drainage. Occasional venous drainage is observed in case of obstruction of the usual collectors. Anatomical obstacles to the drainage, besides thrombosis and tumors, are essentially: compression of the left common iliac vein by the right common iliac artery, and direct compression of the inferior vena cava by the uterus during pregnancy which compresses it against the spine. It is responsible for gravidic postural shock, and an increased abdominal pressure, exceeding 20 mmHg. The main supply pathways are the ovarian veins and the vertebral plexi. This large, low-pressure avalvular plexus may function easily in both directions caudo-cranial and cranio-caudal. The relationship of this plexus with the roots of the sciatic nerve explain certain sciaticas during pregnancy. Dilatation of the ovarian veins during pregnancy cause a so called syndrome of the ovarian vein. Various venous compressions during pregnancy are responsible for some hematurias, increased collateral abdominal circulation, and turgescent haemorrhoids and vulvar varicose veins.

The venous system becomes deformed and distended under the effect of neighboring tissues and hydrostatic pressure. It is thus under a constant threat of stasis. While lying-down at rest, the venous blood is propulsed by means of the pressure gradient maintained by the vis a tergo and the vis a fronte, modulated by the parietal tonus. While standing and stationary, decompensation occurs despite the bulbar reflexes, despite lymphatic resorption and despite the counter-pressure of the perivenous tissues. However, muscular activity and especially walking at a steady pace, restores the resorption of the interstitial liquids, tanks particularly to the musculovascular synergy or the peripheral heart.

The direction of venous return was monitored continuously by the Doppler method at 4 MHz, in order to study the effects of posture and certain kinesitherapeutic maneuvers on venous return in the foot of young, healthy and trained adults (kinesitherapy monitors, yoga assistants). It was noted that: the acceleration of venous return in the foot was expiratory in the recumbent position and inspiratory in the standing position; dorsiflexion (leg on foot or toes on heel) caused a more pronounced spurt phenomenon than plantar flexion; massage repeated at high frequency is less beneficial for venous return than slower massage, which allows better adaptation of venous compliance.

Muscular exercise leads to increased arterial output and is accompanied by capillary vasodilatation. Under these conditions the return circulation must adapt in order to fulfill its role of drainage. Primarily this is brought about by changing the properties of the vein walls: at the level of the venule there is a reduction in smooth muscle tone while at the level of the collecting veins there is an increase in vein wall elasticity. Secondly there is co-ordination of the muscle pump effect such that it matches the exerted effort. A special mode of flow results: at the level of the deep veins the flow becomes pulsatile. If the degree of muscular activity is prolonged and intesnse this "arterialisation" may reach the superficial veins. These adaptations require a venous system which is in perfect condition with regard to its ability to respond properly to the demands placed upon it.

Since chronic venous insufficiency is a constitutional disorder, the principles of healthy living can be of major importance in its prevention and treatment. Among these, the influence of physical activities has attracted the attention of the author, who has attempted to analyze the mechanisms of each sport in order to study its effects on the peripheral vessels. As a result of long terme comparative studies, he has been able to classify the various sports into two categories, the sports which are beneficial and those which are harmful in subjects with vulnerable veins. Into the first category come those activities which assist the physiological mechanisms assuring the return of venous blood, in particular walking, swimming, cycling and gymnastics. Into the second category come sports which involve risks of constriction, trauma, and jolting of the vertebral column (skating, rugby, tennis, etc.), as well as all competitive sports because of the risks of thromboses, often unrecognized, and of excessive efforts which strain the valvular mechanism.

Venous physiology is generally neglected and badly studied. Knowledge of it is nevertheless essential in pathological cases such as venous incompetence and its treatment. It is this which is principally responsible for cardio-vascular adaptation after positional changes. Mercury gauge venous occlusion plethysmography has contributed certain progress. Postural mercury gauge plethysmography without venous occlusion answers the chief physiological preoccupations. No artefact impedes the physiology. The positional adaptation is tested. A DV/DP diagram is established and compared in normal subjects and patients with venous incompetence. A complementary procedure for a microcirculatory study is proposed: the measurement of cutaneous flux using laser Doppler or photoplethysmography and a study of the permeability of the capillary walls using fluorescein videodensitometry. This veritable testing stand of the venous system can serve as reference for procedures of therapeutic tests for all medication for venous tropism (vasotonics, vasodilators of venous location) or in studies on spatial medicine.

While phlebological problems have up to the present time excited relatively little interest in sports medicine, a more careful study does show the importance of phlebology. The present study seeks to emphasise this importance, presenting both the physiological aspects and the traumatological problems affecting the venous system in the athlete. In practice, a fundamental question arises, namely the necessity to determine once and for all whether the venous swelling so often observed in the athlete is or is not a prepathological state. At the present time, the great differences in the various statistics must certainly be due to different interpretations given to the situation.

Plethysmography using the mercury gauge was applied to measure the changes of volume in the calf caused by venous congestion at varying pressures, achieved using an inflated pneumatic band round the thigh. By analysing the deposit graphs, it is possible to calculate a value for the circulatory resistance of the venous system. The significance of this parameter, notably for the diagnosis of venous thrombosis, is explained.

Following a nosological discussion of the varicose vein, its histological, biochemical and immunological elements are detailed. The hydraulic conditions are described, and attention is drawn to the microvasculartissue consequences of the stasis, the degree of constraint exercised by the interstitial tissue, and the role played by the intricate "micro fiber" network of the microcirculation: only a part of the capillaries reconnect with the veinlet of the same circulatory unit, the others having to flow toward the veinlet of other units and only one initial lymphatic vein contributing to the evacuation of 3 to 4 veinlets. The slightest hydraulic imbalance due to the stasis, sets of a whole series of chain reactions that can rapidly become harmful, with chronic veinous deficiency setting in.

Return circulation is studied by describing observed flow solutions: --The direction of the flow is orthograde from the periphery to the right heart, but there ar some inversions. --This permanent flow allows numerous transitory interruptions. --This is a modulated flow, becoming oscillatory in the central veins, and therefore "non-stationary". --Its condition is not exactly laminar. Finally, the venous circulation could be called a "slow-speed system".