By hemodynamic monitoring of liver transplantation with Color Doppler ultrasound, we observed the hemodynamic changes pre- and post-operatively and the patency of the anastomotic vessels, to detect or exclude the presence of complications, then assess the prognosis. We measured the hepatic blood flow after orthotopic liver transplantation in recent 6 cases, and observed the patency of anastomostic vessels and the hemodynamic improvement of the portal vein and hepatic arteries. The abnormal liquid and solid echoes were not found around the transplantated liver in all 6 cases. The echoes of hepatic parenchyma and tububes were normal. The direction and speed of blood flow were also normal. Five of anastomoses of portal vein in 6 cases were patent. The rest one was a little stenosed, and the speed of local blood flow was a little faster. There were 11 patent ones and 1 mildly stenosed in the 12 anastomoses of inferior venae cavae. The speed index(SI) and resistance index(RI) of hepatic arterial blood flow distal to the anastomoses were all normal. Liver transplantation is the redical therapying of portal hypertension, and the color Doppler ultrasound is the best non-invasived method for monitoring the hemodynamic changes of transplantated liver.
Adult ; Female ; Humans ; Liver ; diagnostic imaging ; physiology ; Liver Circulation ; Liver Transplantation ; diagnostic imaging ; Male ; Middle Aged ; Monitoring, Physiologic ; Ultrasonography, Doppler, Color ; Vascular Patency

OBJECTIVETo compare the grafts' blood flow after on-pump and off-pump coronary artery bypass graftings.

METHODSFive hundred and forty-seven cases were studied, including four hundred and three cases undergoing off-pump coronary artery bypass (OPCAB, off-pump group) and one hundred and forty-four cases undergoing on-pump coronary artery bypass (CCABG, on-pump group). In all cases left internal mammary artery (LIMA) was routinely anastomosed to left anterior descending artery (LAD), and saphenous vein (SV) to the other target vessels in sequential mode when there were more than two anastomoses. After all anastomoses were completed and hemodynamic status was stable, transit time flow-meter was utilized to measure and record the grafts' flow wave, pulsatility index (PI), value of mean flow, diastolic and systolic peak flow, vascular resistance, insufficiency ratio and mean blood pressure.

RESULTSPI, insufficiency ratio and diastolic peak flow of LIMA in off-pump group were 2.7 +/- 1.8, (2.2 +/- 4.3)%, (46.8 +/- 2.7) ml/min respectively; those in on-pump group were 2.8 +/- 2.0, (3.4 +/- 3.1)% and (52.8 +/- 3.7) ml/min respectively. And those of SV in off-pump group were 2.8 +/- 0.1, (1.8 +/- 0.3)% and (85.8 +/- 3.2) ml/min respectively and those in on-pump group were 2.6 +/- 0.2, (1.3 +/- 0.2)% and (93.9 +/- 5.6) ml/min respectively. For both LIMA and SV grafts' blood flow there was no significant difference in PI, insufficiency ratio, diastolic peak flow and mean blood pressure in both groups (P > 0.05). The mean flow and systolic peak flow in off-pump group were significantly less than those in on-pump, while the vascular resistance in off-pump group was significantly greater than that in on-pump group (P < 0.01).

CONCLUSIONThere is no significant difference in grafts' patency between OPCAB and CCABG.

Adult ; Aged ; Aged, 80 and over ; Coronary Artery Bypass ; Coronary Artery Bypass, Off-Pump ; Female ; Humans ; Male ; Mammary Arteries ; physiology ; transplantation ; Middle Aged ; Monitoring, Intraoperative ; Regional Blood Flow ; Saphenous Vein ; physiology ; transplantation ; Vascular Patency ; Vascular Resistance

OBJECTIVE: Evaluating the function of the internal jugular vein after selective neck dissection on patients affected by squamous cell carcinoma of the head and neck by color Doppler ultrasonography. METHOD: Forty patients (76 internal jugular veins) who had undergone bilateral selective neck dissection(36 patients) or unilateral selective neck dissection (4 patients) were collected and divided into 2 groups depending on operation area. Group A consisted of 39 internal jugular veins (IJVs) which dissected level II, III and group B included 37 IJVs which disseted level II - IVor II - V spring the IJV. All patients underwent Doppler ultrasonography before and after selective neck dissection at the 1st and 3rd postoperative months. The following measurements were assessed in each test: presence of thrombosis, expiratory jugular flow, expiratory caliber, area both during expiratory and Valsalva maneuver, expiratory flow speed, Valsalva flow speed. All data were statistically analyzed in two groups by comparisons of preoperative conditions and postoperative conditions. RESULT: (1) None of the 76 internal jugular veins showed thrombosis before or after selective neck dissection. (2) Patency rate at the 1st and 3rd postoperative months were respectively 85.5% and 96.1%. Patency rate of the internal jugular vein in two groups showed no significant changes at the 1st and 3rd postoperative months (P > 0.05). (3) In group A, Valsalva flow speed showed no significant changes at the 1st postoperative months (P > 0.05), compared with preoperative; The remainings showed significant difference. Expiratory calibe, area during Valsalva maneuve, expiratory flow speed and Valsalva flow speed had significant difference at the 3rd postoperative months (P < 0.05), compared with preoperative. In group B, Valsalva flow speed showed no significant changes at the 1st postoperative months (P > 0.05), compared with preoperative; The remainings showed significant difference. Expiratory jugular flow had no significant difference at the 3rd postoperative months (P > 0.05), compared with preoperative; The remainings showed significant difference. All parameters at the 3rd postoperative months had significant difference compared with 1st postoperative months between these two groups, excepting expiratory flow speed. (4) Differences of the operation area had no significant impact on indications of the internal jugular vein (P > 0.05). CONCLUSION (1) None of the internal jugular veins showed thrombosis after selective neck dissection. The results indicate that thrombosis of the internal jugular veins can be avoided though careful operation, proper operative skill, appropriate management postoperation. (2) Although most of the parameters changed at early stage after selective neck dissection, many of them improved at the 3rd postoperative months, and expiratory jugular flow recovered to the normal range. The results indicate that the internal jugular veins can basically maintain its normal function at long time postoperation.
Carcinoma, Squamous Cell ; surgery ; Head and Neck Neoplasms ; surgery ; Humans ; Jugular Veins ; diagnostic imaging ; physiology ; Neck Dissection ; adverse effects ; Postoperative Period ; Regional Blood Flow ; physiology ; Ultrasonography, Doppler ; Vascular Patency ; Venous Thrombosis ; prevention & control

OBJECTIVETo observe the histopathological changes of a novel small-caliber vascular graft after implantation in canine theca interna under scanning electron microscope.

METHODA 3 cm segment of the vascular graft (diameter of 4 mm) was implanted in an end-to-end fashion to bridge the severed carotid artery in 19 healthy dogs. Color Doppler sonography was performed 2 weeks after the operation to observe the patency rate of artificial blood vessel. At 1, 8, 12 and 24 week postimplantation, the arteries (4, 4, 6 and 5, respectively) were collected for optical and scanning electron microscopies after angiography to observe the patency of the arteries.

RESULTSOf the total of 19 arteries, occlusion occurred in 1 at 12 weeks and 1 at 24 weeks. Optical and electron microscopies showed that 1 week after implantation, slight fibroplasias and formation of red thrombus could be seen at the vascular anastomosis without endothelial cell lining. At 8 weeks, the host tissue grew into the lumen of the graft through the pores to form uniform neointima consisting of plenty of collagen fibers, but still without endothelial cells. At 12 weeks, discontinuous endothelial cells were seen to grow on the surface of the neointima. In the middle segment of the vascular graft, immature endothelial cells were found to grow in clusters. The structure of the neointima was loose in comparison with that at the anastomosis, with occasional inflammation cells. Twenty-four weeks after grafting, endothelial cells grew over the entire inner wall of the patent graft, and the surface of the neointima at the anastomosis was lined with continuous endothelial cells.

CONCLUSIONThe vascular graft can be useful for reconstruction of canine carotid artery defect and achieves good endothelialization 24 weeks after implantation.

Animals ; Blood Vessel Prosthesis ; Blood Vessel Prosthesis Implantation ; methods ; Carotid Arteries ; diagnostic imaging ; physiology ; surgery ; Collagen ; metabolism ; Dogs ; Endothelial Cells ; cytology ; metabolism ; ultrastructure ; Microscopy, Electron, Scanning ; Models, Animal ; Time Factors ; Tunica Intima ; cytology ; metabolism ; ultrastructure ; Ultrasonography, Doppler, Color ; Vascular Patency

Aged ; Atherosclerosis ; Case-Control Studies ; Coronary Artery Bypass ; methods ; Coronary Artery Disease ; surgery ; Female ; Hemodynamics ; physiology ; Humans ; Male ; Mammary Arteries ; physiology ; transplantation ; Middle Aged ; Pulsatile Flow ; Radial Artery ; physiology ; transplantation ; Rheology ; Saphenous Vein ; physiology ; transplantation ; Shear Strength ; Stress, Mechanical ; Vascular Patency ; physiology

OBJECTIVE: This study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency. MATERIALS AND METHODS: Between May 2005 and June 2014, after stent placement for the treatment of IVCS with acute ilio-femoral deep vein thrombosis, follow-up CT venography was performed in 48 patients (35 women, 13 men; age range 23-87 years; median age 56 years). Using follow-up CT venography, the degree of the stent compression was calculated and used to divide patients into two groups. Possible factors associated with stent compression and patency were evaluated. The cumulative degree of stent compression and patency rate were analyzed. RESULTS: All of the stents used were laser-cut nitinol stents. The proportion of limbs showing significant stent compression was 33%. Fifty-six percent of limbs in the significant stent compression group developed stent occlusion. On the other hand, only 9% of limbs in the insignificant stent compression group developed stent occlusion. Significant stent compression was inversely correlated with stent patency (p < 0.001). The median patency period evaluated with Kaplan-Meier analysis was 20.0 months for patients with significant stent compression. Other factors including gender, age, and type of stent were not correlated with stent patency. Significant stent compression occurred most frequently (87.5%) at the upper end of the stent (ilio-caval junction). CONCLUSION: Significant compression of nitinol stents placed in IVCS highly affects stent patency. Therefore, in order to prevent stent compression in IVCS, nitinol stents with higher radial resistive force may be required.
Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Iliac Vein/pathology/*radiography ; Kaplan-Meier Estimate ; Male ; May-Thurner Syndrome/*diagnosis/radiography/*therapy ; Middle Aged ; Phlebography ; Retrospective Studies ; Stents/adverse effects ; Tomography, X-Ray Computed ; Treatment Outcome ; Vascular Patency/*physiology ; Venous Thrombosis/radiography/*therapy ; Young Adult