Dynamic pressure in the superficial and deep crural veins in uncomplicated varicosity without incompetence of communicant veins

Synchronous phlebotonometry was performed on 30 lower extremities in 27 patients. Various pressure dynamics was observed in the proximal and distal segments of profound veins. Dynamic phlebohypertension was found not only in superficial but also in deep-seated veins. The escape of superficial veins resulted in normalization of pressure in both systems. The more intensive muscle contractions under conditions of normal blood circulation the greater a reduction of pressure phases in the crural vein distal segment this factor may be used as a test for estimation of the vein-muscle pump function.     

Flow in pulmonary veins

Pulmonary venous flow can be evaluated by means of pulsed Doppler echocardiography during a transthoracic or transesophageal echocardiography examination. In most cases a three-peak spectral curve with highest positive wave during ventricular systole, a lower positive wave during ventricular diastole and a small negative wave during the left atrial contraction are recorded. Multiple factors affect the systolic and diastolic components of pulmonary venous flow. Pulmonary venous flow measurement may prove to be an important tool in routine judgment of diastolic left ventricular and atrial function. With regard to clinical importance, the pulmonary venous flow is a useful parameter for left atrial pressure quantification and for differential diagnosis of restrictive cardiomyopathy and constrictive pericarditis.     

Anatomic arrangement of the hepatic veins in the goat

In gross anatomic and angiographic examinations of the hepatic veins of 15 goats, the following were seen: (i) The middle hepatic vein was formed by the contribution of two main branches, one branch coming from the quadrate lobe and the other branch from the right lobe. (ii) There were two right hepatic veins, one of them running along the caudate process and the other formed by branches coming from the dorsal part of the right lobe. (iii) The entrance of the middle hepatic vein, as well as the entrance of the left hepatic vein into the caudal vena cava were partly covered by valvelike membranous flaps.     

Sclerosis in varicose veins

The authors report their experience in the sclerotherapy of varicose veins. They have used the technique of French school: with the patient half sitting, direct puncture not far from the gulf of saphena without tourniquet, on a weekly basis.     

Spontaneous pulsation of the retinal veins

The classical theory of spontaneous pulsation of the retinal veins is that during systole intraocular pressure exceeds venous pressure, causing the veins to collapse. We show that this theory is internally inconsistent and not in accord with experimental data. It is inconsistent in assuming both (a) that oscillations of intraocular pressure (IOP) occur because the veins cannot immediately discharge the systolic arterial inflow and (b) that retinal venous pressure (RVP) can fluctuate independently of IOP during the cardiac cycle. It is not in accord with experimental data, which shows that RVP always exceeds IOP and that fluctuations in the latter are instantly transmitted to the former. We present an alternative theory that does not have these problems. We assume the following. (1) Inflow to the retinal venous tree from the capillaries is constant, the pulsatile arterial flow having been completely damped by the arterioles and capillaries. (2) Outflow from the central retinal vein (CRV) varies during the cardiac cycle because oscillations of IOP, transmitted to the intraocular CRV, are of greater amplitude than oscillations in cerebrospinal fluid pressure, transmitted to the extraocular CRV. By showing that the radial blood flow distending the veins obeys a diffusion equation and by employing an "equivalent cylinder" analysis of the branched venous tree to simplify the boundary conditions, we demonstrate that, with the above assumptions and the additional assumption of low amplitude of radial flow, the CRV will pulsate, and the pulsations will remain confined to a small segment near the exit point. The proposed theory can explain disappearance of pulsation with intracranial hypertension, intensification of pulsation in glaucoma, and variability in the linear extent and amplitude of pulsation among normal individuals. The theory may also be applied to other venous pulsations, such as the respiratory pulsation of the terminal portions of large veins entering the thorax or the cardiac cycle pulsation of the superior vena cava.     

Superficial veins of the lower limbs

This study, limited to the superficial veins of 123 limbs (108 normal and 15 suffering from frank varicose disease) and only vessels with a caliber of at least 2 mm, reveals a certain degree of constancy of anatomical pattern. The initial network is defined embryologically and subsequent haemodynamic phenomena model the final veins. In particular, the topography of the main perforating veins is relatively fixed. Due to their double antihypertensive valve and aspirating pump function while walking, these vessels drain into saphenous veins. They are beneficial when they return reflux into the deep vessels. Conversely, perforator incompetence contaminates the superficial network in the case of deep reflux. The perforating vessels also have a relatively fixed position in relation to other structures: the main saphenous collateral veins, their duplicated branches, their communicating veins and the main valves. This results in large junctions typically associating a saphenous valve, one or several collateral veins, one or several communicating veins, and one or several perforating veins. Typical examples are the garter junction for the long saphenous vein, and the junction of the tip of the calf for the short saphenous vein. Other haemodynamic levels are situated at various sites, particularly in the leg, reflecting the existence, in some cases, of symmetrical "mirror", medial and lateral perforating veins. Morphological analysis of 15 limbs with obvious varicose veins of the trunk of the long saphenous vein defined the routes of transmission of reflux to the leg. Finally, the authors present several technical considerations which they hope will be useful for Doppler operators and surgeons.     

Ultrasonography of veins

PURPOSE: The high incidence of acute and chronic diseases of the venous system requires the application of reliable, non-invasive, low-cost methods in diagnosis and follow-up after therapy. MATERIAL AND METHODS: Current technology, principles of examination, and results of ultrasonography of the peripheral venous systems are reviewed. RESULTS: Since the mid 1980s, compression ultrasonography (US) has been introduced in the diagnosis of deep venous thrombosis. Doppler-US methods reach the hallmarks of venous imaging, particularly since the advent of color duplex US. In thrombosis, postthrombotic syndrome, and primary varicosis, color duplex US increasingly replaces the "gold standard" of phlebography as the imaging method of choice. Venous diseases of the neck, and of the upper and lower extremities are reliably recognized by color duplex US. New areas of application of Doppler and duplex-US include examinations of the venous system in patients in intensive care units, evaluation of transplanted organs, and the demonstration of blood flow in hemodialysis shunts. CONCLUSIONS: Color duplex US is useful in most imaging investigations of the peripheral veins. In view of cost development in the medical imaging sector, however, in which ultrasonography takes a major part, critical indication for the application of Doppler- and duplex-US in the diagnosis and follow-up of venous disease is out most importance.     

Doppler ultrasound of blood flow in the hepatic veins

The blood flow in the hepatic veins can normally be studied easily by Doppler ultrasound. The pattern of blood flow in normal individuals is described, and its relation to the cardiac cycle and changing pressure in the right atrium. The blood flow shows variations in healthy persons, and may change in cases of heart disease and hepatic disease. Conditions such as atrial fibrillation, tricuspid regurgitation, abnormal relaxation, restrictive cardiomyopathy, constrictive pericarditis and cardiac tamponade are reflected in the hepatic veins, and the pattern of blood flow may help in diagnosis, and in grading the pathology. In cirrhosis and portal hypertension the heart-synchronous variation in velocity is reduced. This is due to increased resistance to blood flow across the liver and the pressure gradient becoming larger than the variations in pressure in the right atrium.     

Recurrent varicose veins in the groin after surgery

Bloom syndrome (BLM) is a genetic disorder associated with predisposition to cancer and chromosome instability. However, the most readily recognized clinical feature of the syndrome is growth retardation. Introduction of the previously cloned BLM gene into BLM cells yielded correction of the chromosome instability and slow growth phenotypes. Additionally, asynchronous cultures of complemented clones revealed a lower percentage of cells in S-phase than uncomplemented BLM cells. These results support the notion that BLM is a defect in which short stature, chromosome instability and cancer predisposition are all associated with an error in DNA replication.     

Chloroquine-induced venodilation in human hand veins

OBJECTIVE: Hypotension induced by parenteral administration of chloroquine is a common and serious adverse effect of this drug. Our aim was to investigate whether chloroquine produces venodilation in vivo and to explore the underlying mechanisms. METHODS: Vascular effects of chloroquine were studied in healthy volunteers with use of the dorsal hand vein technique at the Geriatric Research Education and Clinical Center, Veterans Affairs Palo Alto Health Care System. We studied 22 healthy volunteers (19 men and three women). Venous responsiveness was determined with the dorsal hand vein technique, which measures the diameter of the vein. RESULTS: Chloroquine was found to produce a dose-dependent relaxation of hand veins preconstricted with the alpha 1-receptor selective agonist phenylephrine. The venodilatory response to chloroquine ranged from 15% +/- 19% at an infusion rate of 0.75 microgram/min to 61% +/- 24% at 48 microgram/min. Venodilation was attenuated by the nitric-oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) so that the dose of chloroquine required to produce 20% venodilation was increased from 3.7 micrograms/min to 15 micrograms/min (p < 0.01). In the presence of a combination of histamine receptor antagonists, there was also a diminution of the vasodilatory response to chloroquine from 72% +/- 5% to 44% +/- 5% at the infusion rate of 96 micrograms/min. The response was further reduced to 33% +/- 7% by the coinfusion of H1-/H2-receptor antagonists with L-NMMA. CONCLUSION: Chloroquine produces venodilation at infusion rates that achieve local concentrations likely similar to those observed systemically after clinically relevant intravenous doses. The date also suggest a role for nitric oxide and histamine release in mediating this response.     

Thrombosis of the intraorbital veins and cavernous sinus

Eight cases with phlebographic appearances consistent with aseptic thrombosis of the cavernous sinus or of the posterior part of the superior ophthalmic vein are presented. The clinical course is briefly described and the phlebographic findings and possible differential diagnoses discussed. Even if recent methods may obviate the need for phlebography in the demonstration of orbital tumors in certain cases, the possibility of intraorbital or cavernous sinus thrombosis constitutes an important indication for phlebography.     

Investigations on the pathogenesis of primary varicose veins

The data from the clinical course and epidemiology of primary varicose veins of lower limb suggest that sex hormones can directly influence the development of the disease through their intracellular receptor localised in cells of venous wall. The purpose of this study was to determine the stereometric differences in the structure of healthy and varicose veins of lower limb and to determine the presence and localisation of oestrogen and progesterone receptors in the cells of vein. The segments of greater saphenous vein obtained from the 8 women operated for varicose vein were used for the study. The segments of the greater saphenous vein obtained from 8 women that underwent femoro-popliteal venous bypass procedure were used as control group. The vein samples for stereometric analysis were preserved in Buin's solution, embedded in paraffin and then evaluated with automatic analyser MagiCal. To determine the presence of oestrogen and progesterone receptors the immunohistochemic analysis LAB with monoclonal antibodies produced by DAKO was used. The decreased smooth muscle fraction in venous wall, thickening of adventitia, the change of the smooth muscle cells to stroma cells ratio in the muscular layer of venous wall and change of muscular layer to adventitia ratio were observed in varicose veins in comparison with control group. The oestrogen receptors were found in the nuclei of the smooth muscle cells and endothelium. The progesterone receptors were localised in nuclei of smooth muscle cells and cells of subendothelial layer. It seems that quantitative analysis of sex hormones receptor in the venous wall could be useful in the determination of patients with increased risk of the development of primary varicose veins.