Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “VEINS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMedDate not supplied

Morphological alterations of non-varicose and varicose veins. (A morphological contribution to the discussion on pathogenesis of varicose veins).

Venous valves do not play a role in pathogenesis of primary varicose veins. Their number remains constant during life time. In varicose veins their insufficiency is secondary. Intimal fibrosis is no prerequisite for the development of varicose veins. It is a frequent finding in non-varicose veins of all age groups. Fibrosis of media and adventitia is no early morphological alteration in varicose veins. Fibrotic replacement of smooth muscles represents a late stage of varicosis. Degenerative lesions of deep leg veins are rare even at old age. The deep veins are not influenced by sclerotic lesions of the adjacent arteries. Preexisting intimal fibrosis in autogenous graft veins may be one of several factors which induce an overshooting intimal proliferation. Degenerative alterations (fibrotic lesions of the wall layers, insufficiency of the valves) are secondary phenomena in pathogenesis of varicose veins which follow a functional deficiency of the smooth musculature.

Adolescent↗
PubMed1991

Rat femoral vein-to-vein grafts as a microvascular practice model: factors that influence patency.

The rat femoral vein has become a standard model for microvascular anastomosis practice as well as for research investigations into various manipulative influences upon venous patency. Although vein grafts to the rat artery are the focus of many experimental studies, few reports have investigated vein-to-vein grafts. This study examines the short-term patency (1-3 days) of vein grafts interpositioned to the rat femoral vein. Several factors are studied for their ability to alter the patency rate. The results indicate that patency is difficult to achieve following the creation of a second serial anastomosis (construction of a vein-to-vein graft). Systemic heparin consistently improves patency rates, and trends toward increased patency are seen for reduction in longitudinal tension of the repaired vessel. It is also implied that a deeper understanding of venous hemodynamics and thrombotic events may lead to improved methodologies in the clinical applications of microvenous repairs. These results indicate that rat vein-to-vein grafts may provide a challenging microvascular training model, while introducing the novice microsurgeon to some of the complicating factors encountered with microvascular grafting.

Anastomosis, Surgical↗
PubMedDate not supplied

Aneurysms of the portal vein and superior mesenteric vein.

Only scattered reports of portal vein and superior mesenteric vein aneurysms appear in the literature. Case reports of three patients with portal vein and superior mesenteric vein aneurysms diagnosed by computed tomography (CT) and gray-scale, color Doppler, and duplex Doppler sonography are presented. In one case, an isolated portal vein aneurysm was demonstrated. In the second case, an aneurysm of the portal vein and superior mesenteric vein resulting in biliary ductal dilatation was observed. In the third case, an isolated superior mesenteric vein aneurysm was found. None of the patients had a history or clinical evidence of underlying liver disease, pancreatitis, or other disease states that would predispose them to the development of aneurysms. The clinical presentations, possible etiologies, and imaging features of portal vein and superior mesenteric vein aneurysms are reviewed. The value of CT and sonography in the detection and characterization of these rare aneurysms is discussed.

Adult↗
PubMed2003

Facial vein draining into external jugular vein in humans: its variations, phylogenetic retention and clinical relevance.

The superficial veins, especially the external jugular vein (EJV), are increasingly being utilized for cannulation to conduct diagnostic procedures or intravenous therapies. Ultrasound-guided venipuncture is a viable possibility in cases of variations in the patterns of superficial veins, and their knowledge is also important for surgeons doing reconstructive surgery. This study was done on 89 dissected adult cadavers (178 sides) and variations in patterns of termination of the facial vein (FV) into the EJV were studied. The FV in 16 sides (9%) was found to drain into the EJV, in two main patterns: type I and type II. Type I had the FV draining into the EJV with varying degrees of obliquity in a Y-shaped (6 cases, 37.5%), U-shaped (3 cases, 18.7%), tuning-fork-shaped (2 cases, 12.5%) or N-shaped (1 case, 6.2%) pattern. Type II showed an inverted A-shaped pattern (2 cases, 12.5%) or a stepladder-shaped pattern (2 cases, 12.5%) depending on the presence of one or more connecting conduits between the FV and EJV respectively. In Macaca mulatta(rhesus monkey) a pair of vertically disposed, subcutaneous veins placed nearly side by side and of equal caliber were seen on each side of the neck. The lateral vein was the EJV while the medial one took the course of the FV in the upper oblique segment and ran parallel to the EJV in the lower segment over the sternocleidomastoid, with one or two transverse communications. The anomalous patterns found in our study could be explained in terms of the regression and retention of various parts of the veins found in the rhesus monkey, or the drainage pattern found in horse, ox and dog, where the vein from the face drain into the external jugular vein, the internal jugular vein being either absent or a small vessel accompanying the carotid artery.

Adult↗
PubMed1995

Differences in the effects of ketanserin and GR127935 on 5-HT-receptor mediated responses in rabbit saphenous vein and guinea-pig jugular vein.

Ketanserin has higher affinity for 5-HT1D alpha receptors compared to 5-HT1D beta receptors, whereas, GR127935 (N-[4-methoxy-3-(4-methyl-1-piperazinyl)phenyl]-2(methyl-4(-(5-methyl- 1,2,4-oxadiazol-3-yl)[1,1-biphenyl]-4-carboxamide), a novel and selective 5-HT1D receptor antagonist, has higher affinity for 5-HT1D beta receptors compared to 5-HT1D alpha receptors. In the present study, we compared the effects of ketanserin and GR127935 on sumatriptan-induced responses of rabbit saphenous vein and guinea-pig jugular vein. In rabbit saphenous vein, contractile responses elicited by sumatriptan were antagonised by ketanserin (pA2 = 6.76) and GR127935 (apparent pA2 = 9.4). In guinea-pig jugular vein, concentration-dependent relaxations evoked by sumatriptan were antagonised by ketanserin and GR127935 (apparent pA2 = 5.9 and 10, respectively). Ketanserin but not GR127935, inhibited Ca(2+)-induced contraction of depolarised strips of guinea-pig ileum longitudinal muscle/myenteric plexus, however, in rabbit saphenous vein and guinea-pig jugular vein, 5-HT receptor mediated responses were insensitive to nifedipine (Ca2+ channel blocker), eliminating the possibility that the inhibitory effects of ketanserin and GR127935 were due to the blockade of voltage-operated Ca2+ channels. Thus, antagonism by ketanserin and GR127935 confirms the presence of 5-HT1D receptors in rabbit saphenous vein and guinea-pig jugular vein. The differential effects of ketanserin and GR127935 on responses elicited by sumatriptan in rabbit saphenous vein and guinea-pig jugular vein may reflect either species differences in 5-HT1D receptors or the involvement of 5-HT1D alpha and 5-HT1D beta receptor subtypes.

Animals↗
PubMed2005

Valsalva and gravitational variability of the internal jugular vein and common femoral vein: ultrasound assessment.

PURPOSE: Central venous cannulation via the common femoral vein is an important starting point for many interventions. The purpose of this study was to determine the optimum conditions for cannulation of the femoral vein and to compare these with the relative changes in the internal jugular vein. METHODS: High-resolution 2D ultrasound was utilised to determine variability of the calibre of the femoral and internal jugular veins in 10 healthy subjects. Venous diameter was assessed during the Valsalva manoeuvre and in different degrees of the Trendelenburg position. RESULTS: The Valsalva manoeuvre significantly increased the size of the femoral and internal jugular veins. There was a relatively greater increase in femoral vein diameter when compared with the internal jugular vein of 40 and 29%, respectively. Changes in body inclination (Trendelenburg position) did not significantly alter the luminal diameter of the femoral vein. However, it significantly increased internal jugular vein diameter. CONCLUSIONS: Femoral vein cannulation is augmented by the Valsalva manoeuvre but not significantly altered by the gravitational position of the subject.

Adult↗
PubMed1999

Diameter-reflux relationship in perforating veins of patients with varicose veins.

PURPOSE: Treatment of chronic venous valvular insufficiency requires understanding of the hemodynamics of perforating veins. To preserve normal veins or veins that can function normally once primary sources of valvular insufficiency are removed, a better understanding of the diameter-reflux relationship is desirable. We measured reflux and diameters in 500 perforating veins of patients with varicose veins (C(2)E(P)A(SP)P(R)). METHODS: Color flow duplex ultrasonography scanning was performed with the patient standing. Perforating veins were mapped medially in the thigh and medially, laterally, and posteriorly in the calf. Reflux was defined as reverse flow that lasted longer than 0.5 seconds. Diameters were measured on B-mode transverse projections at the crossing of the fascia. Competent versus incompetent vein diameters were compared by means of Student t test, one-way analysis of variance, and Bonferroni t test. RESULTS: Diameters of competent and incompetent perforators averaged 2.5 +/- 0.9 mm (n = 17) and 4.7 +/- 1.9 mm (n = 17) at the medial thigh (P <.0002), 2.2 +/- 0.8 mm (n = 179) and 3.7 +/- 1.0 mm (n = 210) at the medial calf (P <.0001), 2.2 +/- 0.6 mm (n = 13) and 3.5 +/- 0.8 mm (n = 37) at the posterior calf (P <. 0001), and 2.1 +/- 0.8 mm (n = 9) and 3.3 +/- 0.7 mm (n = 18) at the lateral calf (P <.003), respectively. Perforating vein diameters of 3.5 mm or larger in the calf and thigh were associated with reflux in more than 90% of the cases. CONCLUSION: An enlargement in the diameter of the perforating veins of 1 to 1.5 mm in the calf or 2 mm in the thigh of patients with varicose veins could be the difference between normal flow and reflux. Further studies are needed to confirm if elimination of reflux in patients with primary varicosity will transform incompetent perforators to competent ones.

Female↗
PubMed1990

Long saphenous vein saving surgery for varicose veins. A long-term follow-up.

The autologous saphenous vein is widely recognised as the graft material of choice in infra-inguinal arterial reconstructions. This study was undertaken to evaluate the long-term results of long saphenous vein saving surgery compared with standard stripping. Forty-two patients with varicose veins were randomly allocated to treatment, either with standard stripping of the long saphenous vein or high ligation. In both groups, local varicosities were avulsed and insufficient perforators ligated, on the basis of physical examination and phlebography. Follow-up was performed 52 +/- 5 months postoperatively. The recurrence rate was 12 and 11% in the stripping and the high ligation group respectively. At follow-up, the venous return time was increased significantly in both groups (P greater than 0.001). Vein mapping by means of high-resolution, real-time ultrasound at follow-up showed that 78% of the preserved saphenous veins were suitable for use as arterial conduits. These results suggest that removal of the long saphenous vein per se is of no therapeutic value if insufficient perforators have been ligated. It is possible to perform elective vein surgery for varicose veins with good results and preserve the long saphenous vein, which in turn can be used for future arterial reconstruction in most cases.

Adult↗
PubMed1996

Neovascularisation is the principal cause of varicose vein recurrence: results of a randomised trial of stripping the long saphenous vein.

OBJECTIVES: To determine whether routine stripping of the long saphenous vein reduces recurrence after varicose vein surgery. DESIGN: Randomised controlled trial. All operations done by a consultant vascular surgeon. Two year follow-up. MATERIALS AND METHODS: One hundred patients with primary long saphenous varicose veins (133 legs) were randomised. Two year follow-up in 81 patients (113 legs) with questionnaire, clinical examination and Duplex scanning. RESULTS: Some 89% remained satisfied with the results of their surgery, though 35% had recurrent veins on clinical examination. Recurrence was reduced from 43 to 25% in patients who had their long saphenous vein stripped (p = 0.04, chi 2). Neovascularisation (serpentine tributaries arising from the ligated saphenofemoral junction) was detected in 52% of limbs and was the commonest cause of recurrence. Most tributaries were less than 3 mm in diameter and only caused recurrence if the long saphenous vein or a major thigh vein was intact. Twelve patients had tributaries greater than 3 mm diameter and all had recurrent varicose veins. CONCLUSIONS: Recurrence is common after varicose vein surgery and in this study was caused principally by neovascularisation at the ligated saphenofemoral junction. Clinical recurrence is reduced by routine stripping of the long saphenous vein.

Adult↗
PubMedDate not supplied

Errors in the differential diagnosis of incompetence of the popliteal vein and short saphenous vein by Doppler ultrasound.

Doppler Ultrasound is now routinely used to demonstrate valvular reflux in the venous system. Incompetence detected at the back of the knee is located either in the short saphenous vein or in the popliteal vein. Whether the incompetence is in the deep or superficial venous system can be differentiated by digital compression over the short saphenous vein in the upper calf; if reflux is abolished then the incompetence is assumed to be in the superficial vein but if it is not prevented it must be in the popliteal vein. Sometimes the reflux is not controlled when the deep system is normal. This has been shown to be due to variations in the anatomy of the short saphenous vein and especially the pattern of its termination. Examples with venography are given, showing that in the presence of incompetence at the sapheno-popliteal junction there may be no reflux in the short saphenous vein; instead the proximal tributaries are involved and reflux in these veins is not controlled by pressure over the short saphenous vein. This explains the false positive diagnosis of valvular incompetence in the popliteal vein.

Adult↗
PubMed1986

Alternative autogenous vein grafts to the inadequate saphenous vein.

Autogenous veins other than single-length greater saphenous vein were used in 150 operations to revascularize the extremities of 138 patients; three operations were for upper extremity ischemia and four were lower extremity reconstructions with lesser saphenous vein grafts. The remaining 143 bypasses were performed to revascularize lower extremities in 131 patients. Arm vein grafts were used in 102 operations, and 14 different combinations of vein segments were used to construct 41 totally autogenous composite vein grafts. Tissue necrosis or rest pain was the indication for 70% of arm vein bypasses; 52% of these grafts extended to an infrapopliteal artery. The 1-, 3-, and 5-year patency rates were 82%, 69%, and 60%, resulting in limb salvage rates of 93%, 91%, and 81%, respectively. Composite autogenous vein grafts resulted in a 1-year limb salvage rate of 79% in a select group of elderly patients with advanced arterial disease, poor runoff, and profound ischemia. Limb salvage was the indication for 93% of these operations; tissue necrosis was present in 71% while 80% required infrapopliteal reconstructions--37% to a peroneal artery and 29% to the ankle or foot. Successful limb salvage has been accomplished with alternative autogenous veins when the greater saphenous vein is missing or inadequate, dramatically reducing the use of prosthetic conduits in our practice.

Aged↗
PubMed2004

Delayed portal vein thrombosis after experimental radiofrequency ablation near the main portal vein.

BACKGROUND: Portal venous blood flow may protect adjacent tumour cells from thermal destruction with radiofrequency ablation (RFA). This study aimed to investigate the local effect of RFA on the main portal vein branch, and the completeness of cellular ablation in its vicinity, with or without a Pringle manoeuvre using a porcine model. METHODS: This was an in vivo study on 23 domestic pigs. RFA using a cooled-tip electrode was performed 5 mm from the left main portal vein branch under ultrasonographic guidance for 12 min with (n = 10) or without (n = 10) a Pringle manoeuvre. Ten pigs were killed 4 h after the procedure to study the early effects of RFA and ten others were killed 1 week later to determine any delayed effect. As a control, sham operations with a Pringle manoeuvre for 12 min were performed on three pigs. The flow velocity changes of portal vein and hepatic artery were measured using Doppler ultrasonography, and the completeness of cellular ablation around the portal vein was assessed qualitatively by histochemical staining and quantitatively by measuring intracellular levels of adenosine 5'-triphosphate (ATP). RESULTS: In the absence of the Pringle manoeuvre, there was no significant change in mean(s.d.) portal vein flow velocity before RFA (20.0(3.5) cm/s) and at 4 h (18.5(2.5) cm/s) (P = 0.210) and 1 week (19.5(2.2) cm/s) (P = 0.500) after the procedure. Gross and histological examination of the portal vein branches showed no damage without the Pringle manoeuvre. In all pigs that underwent RFA with a Pringle manoeuvre, the portal vein was occluded 1 week after the operation; histological examination of the affected portal vein showed severe thermal injury and associated venous thrombosis. The local effect of RFA on the hepatic artery was similar. With intact portal blood flow during RFA, complete ablation of liver tissue around the pedicle was demonstrated by histochemical staining and measurement of the intracellular ATP concentration. CONCLUSION: RFA was safe when applied close to the main portal vein branch without a Pringle manoeuvre, with complete cellular destruction. Use of the Pringle manoeuvre resulted in delayed portal vein and hepatic artery thrombosis and injury to the hepatic artery and bile duct.

Animals↗
PubMed1994

Systemic hypertension and hypercholesterolemia in vein grafts: effects on the function and morphology of experimental vein grafts.

Hypertension and hypercholesterolemia are known risk factors for the development of atherosclerosis and are considered to influence the development of vein graft intimal hyperplasia. This study examines the effect of hypertension (two-kidney, one-clip model for 8 weeks) and hypercholesterolemia (1% cholesterol diet for 8 weeks) individually and in combination on the formation of intimal hyperplasia and the vasomotor function of vein grafts. Forty New Zealand White rabbits underwent a carotid vein bypass graft. Ten were controls, 10 were hypertensive, 10 were hypercholesterolemic, and 10 had both hypertension and hypercholesterolemia. Hypertension and/or hypercholesterolemia were present for 4 weeks prior to and for 4 weeks after surgery. All vein grafts were harvested at 4 weeks postoperatively for histology (n = 6) or contractility studies (n = 4). Compared to controls, hypercholesterolemia increased intimal but not medial thicknesses of the vein grafts and enhanced smooth muscle cell contractility. Hypertension did not increase vein graft intimal or medial thicknesses but did augment vein graft contractility compared to controls. Hypertension with hypercholesterolemia increased intimal and medial thicknesses and enhanced vasoreactivity in vein grafts. The results show that hypertension influences the vasoreactivity but not the development of intimal hyperplasia in vein grafts. When hypertension is combined with hypercholesterolemia, there is both an increase in the medial thickness and an attenuation of vasomotor function compared to hypercholesterolemia alone, although there is no further increase in intimal hyperplasia formation. Therefore, this study suggests that the combination of both atherogenic risk factors does not act synergistically in promoting either the formation of intimal hyperplasia or vasomotor dysfunction in vein grafts.

Animals↗
PubMed1984

Sonography of caudal hepatic veins in children. Incidence, importance and relation to cranial hepatic veins.

In 200 unselected upper abdominal sonographies in children the hepatic venous anatomy was examined with special reference to caudal hepatic veins. In 42% of patients caudal hepatic veins could be demonstrated sonographically, while large caudal hepatic veins could be shown in 12.5% of patients. The large caudal hepatic veins always drained from the posterior-inferior or posterior-lateral parts of the liver complementing the right (cranial) hepatic vein. When the size of the right cranial hepatic vein was small the caudal hepatic vein(s) were large. Sonographic demonstration of a small right hepatic vein is a useful indicator of large caudal hepatic veins, and the relative sizes of the cranial and caudal veins are inversely proportional.

Adolescent↗
PubMed2002

Risk indicators for varicose veins in forty- to sixty-year-olds in the Tampere varicose vein study.

The objectives of the study were to discover the main determinants for the prevalence of varicose veins in a general population, and to assess the possibilities for prevention of this common surgical disease. Varicose veins were evaluated in three defined cohorts of 3284 men and 3590 women aged 40, 50, and 60 years by using a validated questionnaire. The response rate was 75% among men and 86% among women, and varicose veins were determined by self-assessment. Increasing age, female sex, childbirths, standing posture at work, higher weight or height, and positive family history were significantly associated with varicose veins in a univariate analysis. These factors were further taken into a multivariate logistic regression analysis, and female gender (adjusted odds ratio, OR 2.2), increasing age (OR 2.2-2.8), a reported positive family history for varicose veins (OR 4.9), increasing number of births (OR 1.2-2.8), standing posture at work (OR 1.6), and higher weight (OR 1.2) and height (OR 1.4) were found to independent and significant risk indicators of varicose veins. Increasing age, positive family history of varicose veins, and child-births in women were the most important factors in terms of population etiologic fractions. Familial predisposition and pregnancy-related factors bear important associations with varicose veins. Thus prevention of varicose veins appears to be difficult. Varicose veins are nonlethal and, therefore, higher age is related to higher prevalence.

Adult↗
PubMed2004

Pancreaticoduodenectomy with en bloc portal vein resection for pancreatic carcinoma with suspected portal vein involvement.

Pancreaticoduodenectomy combined with portal vein resection is increasingly accepted as a viable treatment option for pancreatic carcinoma with suspected involvement of the portal vein.However, its clinical benefit remains controversial. This study evaluated the outcomes of pancreaticoduodenectomy with portal vein resection for pancreatic carcinoma in a group of Chinese patients operated on by a specialized team in a center with a low case volume of pancreatic cancer. The perioperative and long-term outcomes of 12 patients with portal vein resection for suspected involvement of the portal vein and 38 patients who underwent pancreaticoduodenectomy without portal vein resection during the same period were compared. In the former group, eight patients underwent segmental resection, and four patients underwent wedge resection of the portal vein. There were no significant differences in operative blood loss (median 0.8 vs. 0.8 liter, p = 0.313), hospital mortality (0% vs. 2.6%, p = 1.000), or operative morbidity (41.7% vs. 42.1%, p = 0.979) between the two groups. Patients who required portal vein resection had higher frequencies of microscopic lymphatic permeation (58.3% vs. 18.4%, p = 0.023) and vascular invasion (50.0% vs. 15.8%, p = 0.025). Long-term survival was comparable between patients with portal vein resection and those without it (median 19.5 vs. 20.7 months,p = 0.769). These findings suggest that pancreaticoduodenectomy combined with portal vein resection can be performed safely by a specialized team in a center with a low case volume of pancreatic carcinoma and that it may offer survival benefit in patients with suspected portal vein involvement.

Adenocarcinoma↗
PubMed1987

The healing characteristics of autogenous saphenous vein used in the reconstruction of previously implanted arterial saphenous vein grafts.

Aortocoronary saphenous vein grafts with early isolated stenoses pose the technical problem of how to deal with these grafts at reoperation. The advisability of using a portion of old graft when reconstructing these grafts was examined. An experimental model was devised in which the anatomical and pathological interfaces between fresh vein and previously inserted vein were studied. Superficial femoral artery from the thigh of 15 dogs was replaced by reversed autogenous saphenous vein. Four months later, the animals were divided into two groups. Group 1 consisted of 8 animals that underwent transection and reimplantation of the middle 4 cm of the vein graft in exactly the same position in which it had been. In Group 2, the 7 animals had the middle 4 cm of the graft replaced with newly harvested reversed saphenous vein. Six months after initial vein graft implantation, the animals were studied. No critical stenoses were seen in the grafts. Pathological study of Group 1 grafts revealed fibrous graft disease of uniform severity throughout the graft, thereby demonstrating that new anastomoses in an old graft do not affect graft disease. Group 2 grafts revealed that the severity of disease in the new interposed segment of the vein graft was less than in the old retained portions of the graft. No untoward reaction causing acceleration of graft disease occurred between old and new vein. Operations using undiseased portions of old vein grafts should be considered a viable option in repeat coronary revascularization for early stenoses.

Animals↗
PubMed1998

Reticular veins, incompetent reticular veins, and their relationship to telangiectases.

BACKGROUND: The pathological role that reticular veins, or their incompetent variants, play in the development and progression of telangiectases has been a subject of debate. The implications of their treatment on the disappearance of telangiectases has been a source of confusion. OBJECTIVE: This article explores the anatomical and functional relationship of reticular veins with telangiectases. The evidence for any pathological role that reticular veins, or their incompetent counterparts, play in the appearance of telangiectases is examined. METHODS: Medical literature on reticular veins of the lower extremity was reviewed. The consequences of their treatment on existing contiguous telangiectases and on the development of new telangiectases is discussed. RESULTS: Telangiectases occur both in the absence and presence of incompetent reticular veins. Incompetent reticular veins often exist without any associated telangiectases present. However, when telangiectases and reticular veins, or their incompetent counterparts, appear in close proximity, their intraluminal channels are, almost invariably, in direct communication. CONCLUSIONS: A causal role for reticular veins, or their incompetent counterparts, in the development or progression of telangiectases has not been established. Furthermore, the successful eradication of telangiectases does not depend on the prior or simultaneous eradication of any reticular veins with which they may communicate. Failure to eradicate telangiectases is not due to the persistence of the reticular veins but to inadequate treatment of the telangiectases.

Humans↗