Reconstruction of the portal and hepatic veins using venous grafts customized from the bilateral gonadal veins

Background  

Surgical resection for pancreatic and hepatic cancer sometimes involves combined resection and reconstruction of the major veins using venous grafts. Autologous venous grafts made from the bilateral gonadal veins (BGVs) have never been utilized or discussed.     

The effect of pregnancy on the lower-limb venous system of women with varicose veins.

OBJECTIVES: to assess the effect of pregnancy on the lower-limb venous system of women with varicose veins. Design a longitudinal prospective study of 11 pregnant women, with varicose vein disease. METHODS: eleven pregnant women with varicose veins were recruited as part of a larger study. Veins were assessed in both lower limbs using colour-flow duplex scanning at a 75 degrees head-up tilt. The diameter and velocity and duration of reflux were measured in each vein at 12, 20, 26, 34, 38 weeks gestation and 6 weeks postpartum. RESULTS: eleven women had reflux and varicose veins demonstrated at first scan. All veins dilated with increasing gestation. This was maximal in the superficial system, reaching significance (p相似文献   

Definition of venous reflux in lower-extremity veins

PURPOSE: This prospective study was designed to determine the upper limits of normal for duration and maximum velocity of retrograde flow (RF) in lower extremity veins. METHODS: Eighty limbs in 40 healthy subjects and 60 limbs in 45 patients with chronic venous disease were examined with duplex scanning in the standing and supine positions. Each limb was assessed for reflux at 16 venous sites, including the common femoral, deep femoral, and proximal and distal femoral veins; proximal and distal popliteal veins; gastrocnemial vein; anterior and posterior tibial veins; peroneal vein; greater saphenous vein, at the saphenofemoral junction, thigh, upper calf, and lower calf; and lesser saphenous vein, at the saphenopopliteal junction and mid-calf. Perforator veins along the course of these veins were also assessed. In the healthy volunteers, 1553 vein segments were assessed, including 480 superficial vein segments, 800 deep vein segments, and 273 perforator vein segments; and in the patients, 1272 vein segments were assessed, including 360 superficial vein segments, 600 deep vein segments, and 312 perforator vein segments. Detection and measurement of reflux were performed at duplex scanning. Standard pneumatic cuff compression pressure was used to elicit reflux. Duration of RF and peak vein velocity were measured immediately after release of compression. RESULTS: Duration of RF in the superficial veins ranged from 0 to 2400 ms (mean, 210 ms), and was less than 500 ms in 96.7% of these veins. In the perforator veins, regardless of location, outward flow ranged from 0 to 760 ms (mean, 170 ms), and was less than 350 ms in 97% of these veins. In the deep veins, RF ranged from 0 to 2600 ms. Mean RF in the deep femoral veins and calf veins was 190 ms, and was less than 500 ms in 97.6% of these veins. In the femoropopliteal veins, mean RF was 390 ms, and ranged from 510 to 2600 ms in 21 of 400 segments; however, RF was less than 990 ms in 99% of these veins. Duration of RF was significantly longer in all three veins systems in patients (P <.0001 for all comparisons). With a cutoff value of more than 1000 ms rather than more than 500 ms, prevalence of abnormal RF in the femoropopliteal veins was significantly reduced, from 29% to 18% (P =.002). Thirty-seven vein segments (2.4%) had RF greater than 500 ms in the supine position, compared with less than 500 ms in 22 of these vein segments (59%) in the standing position. Of the 48 vein segments (3.1%) with RF greater than 500 ms in the standing position, RF was less than 500 ms in 6 of these vein segments (13%) in the supine position. Similar observations were noted in patient veins. There was no association between RF and peak vein velocity. Peak vein velocity had no significance in determining reflux. CONCLUSIONS: The cutoff value for reflux in the superficial and deep calf veins is greater than 500 ms. However, the reflux cutoff value for the femoropopliteal veins should be greater than 1000 ms. Outward flow in the perforating veins should be considered abnormal at greater than 350 ms. Reflux testing should be performed with the patient standing.     

Role of venous elasticity in the development of varicose veins

A reduction in the 'elasticity' of the venous system has been proposed as a precursor of venous insufficiency, but the concept remains controversial. This study was designed to develop a method of assessing venous elasticity, and to use this method to investigate the aetiology of varicose veins. Simultaneous measurements of calf volume (determined using strain gauge plethysmography) and venous pressure (obtained via a dorsal foot vein) were made during venous occlusion plethysmography. The elastic modulus, K, defined as stress/strain when the veins are full, was calculated from the pressure/volume relationship. The elastic modulus was determined in 19 normal legs, 33 legs with superficial venous insufficiency, 16 legs with deep venous insufficiency, and 18 legs of a high risk group of volunteers or patients without varicose veins but with a strong history of factors associated with their development. The results showed a clear difference in elasticity between normal limbs and limbs with varicose veins, and also between normal limbs and high risk limbs. These results support the hypothesis that reduced elasticity has a role in the development of varicose veins and precedes the onset of valvular incompetence.     

Predictors of hepatic venous trunk invasion and prognostic factors in patients with hepatocellular carcinomas that had come into contact with the trunk of major hepatic veins

PURPOSE: In this study, we tried to identify the preoperative predictors of hepatic venous trunk invasion and the prognostic factors in patients with hepatocellular carcinoma (HCC) that had come into contact with the trunk of a major hepatic vein over a distance of 1.0 cm or more. METHODS: Forty patients who had such HCCs resected were entered into this study and predictors of hepatic venous trunk invasion and prognostic factors were evaluated by univariate and multivariate analyses. RESULTS AND CONCLUSIONS: A combined resection of the HCC and the venous trunk was performed in 29 patients. Hepatic venous trunk invasion was observed in 12 patients, including 2 with inferior vena cava tumor thrombus. A stepwise logistic regression analysis indicated that tumors larger than or equal to 7 cm in diameter and tumors showing a poorly differentiated histological grade were independent predictors of hepatic venous trunk invasion. The survival of patients without venous trunk invasion was significantly better than that for patients with venous trunk invasion (P = 0.048). A univariate analysis revealed that Child-Pugh classification B (P = 0.002), a high des-gamma-carboxy prothrombin concentration (> or =400 mAU/ml, P = 0.023), a large HCC (> or =5.0 cm in diameter, P = 0.002), the presence of portal vein invasion (P < 0.001), the presence of venous trunk invasion (P = 0.048), the presence of intrahepatic metastasis (P < 0.001), and poorly differentiated HCC (P = 0.006) correlated with a worse overall survival after hepatic resection. In a multivariate analysis, however, only the presence of intrahepatic metastasis (P = 0.037, relative risk 8.25) was an independent predictor of poor overall survival. CONCLUSIONS: Large tumors (> or =7 cm in diameter) and poorly differentiated HCCs were more likely to be associated with hepatic venous trunk invasion and intrahepatic metastasis was an independent prognostic factor in patients with HCC that had come into contact with the trunk of a major hepatic vein.     

Results and significance of colour duplex assessment of the deep venous system in recurrent varicose veins.

OBJECTIVES: To establish the status of the deep veins in patients presenting with recurrent varicose veins and the effect on treatment decisions. DESIGN: Retrospective clinical series. MATERIALS AND METHODS: Duplex examination of 570 consecutive patients (843 limbs) presenting with recurrent varicose veins (CEAP C2-4). RESULTS: Approximately one third of these patients (34.8%:294 limbs) had no deep venous abnormality; 173 limbs with superficial vein abnormalities only had great and/or small saphenous junction incompetence, the remaining 121 legs had abnormal perforating or communicating veins. Deep venous abnormalities were found in 549 limbs with evidence of persisting deep venous obstruction in only 20. Deep venous incompetence was found in 529 limbs (62.7% of all legs). However three segment incompetence (common femoral, femoral and popliteal veins) was found in only 181 legs (21.4%), two segment incompetence in 137 (16.2%) and one segment incompetence in 211 (25%). CONCLUSIONS: Deep vein incompetence is common in patients with recurrent varicose veins. Deep venous obstruction is an infrequent finding but total deep venous reflux (three segment incompetence) affects just under one quarter of all limbs with recurrent varicose veins. Ablation or surgery of varicose veins in this group may be less effective. Patients should be advised of the implications of this finding.     

Extraparenchymal control of hepatic veins during mesohepatectomy

BACKGROUND: Bleeding is the most relevant operative risk during mesohepatectomy because of the wideness of the resection surfaces and the exposure of main intrahepatic vascular structures. Preliminary extraparenchymal exposure of the main hepatic veins, with the possibility of clamping them in association with the Pringle maneuver, and the maintenance of a low central venous pressure during mesohepatectomy, can contribute to substantially reducing operative bleeding. STUDY DESIGN: We report the results obtained in 18 mesohepatectomies, performed for liver metastases (13 patients) and for hepatocellular carcinoma (5 patients). Liver resection was performed without preliminary exposure of the main hepatic veins in nine patients (group A) and with preliminary looping of the main hepatic veins in nine patients (group B), without complications related to the maneuver. RESULTS: Intermittent pedicle clamping was used in all patients; in six patients in group B (66.7%), clamping of the main hepatic veins was also performed (mean duration, 37 minutes; range 16 to 68 minutes). Intraoperative blood transfusions were needed in 5 patients (5 of 18, 27.8%): 4 belonged to group A (44.4%) and 1 to group B (11.1%). Mortality was nil and morbidity was 33.3%, involving four patients in group A and two in group B (none related to the exposure, looping, and clamping of the main hepatic veins). CONCLUSIONS: Preliminary control of the main hepatic veins is a safe maneuver. During mesohepatectomy, clamping of these veins, associated with pedicle clamping, is effective in reducing operative bleeding. In our patients, this resulted in a low blood transfusion rate, similar to that of classic major hepatectomies, despite the higher complexity of mesohepatectomy.     

Hepatic trauma involving the hepatic veins and vena cava

The control of massive haemorrhage in major hepatic injury with caval damage is extremely difficult. Our experience with 5 such patients is reported. The management and operative techniques involved are discussed. In 3 patients control was obtained and repair effected without recourse to internal caval shunting. One of these patients survived in spite of extensive injuries.