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Artery Flow (artery + flow)
Kinds of Artery Flow Selected AbstractsRecovery of Reversed Basilar Artery Flow as Seen by Transcranial Sonography and MRA Source Images for Vertebral DissectionJOURNAL OF NEUROIMAGING, Issue 4 2008Sung Ik Lee MD ABSTRACT The dissection of the intracranial vertebral artery (VAD) is a common cause of young age brain stem stroke. VAD can be detected by conventional angiography, but there is yet no agreement on the most effective tool to use for the detection of VAD. Here, we report a patient with VAD, who was diagnosed with an intimal flap within the left vertebral artery by the magnetic resonance angiography (MRA) source images. Transcranial Doppler (TCD) showed a reversed flow in the basilar artery. After 4 months, TCD and transcranial color-coded Doppler (TCCD) confirmed a normal anterograde flow of the vertebro-basilar arteries. [source] Effect of Hepatic Artery Flow on Bile Secretory Function After Cold IschemiaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2003David P. Foley These studies evaluated the influence of hepatic arterial flow on biliary secretion after cold ischemia. Preparation of livers for transplantation or hepatic support impairs biliary secretion. The earliest indication of cold preservation injury during reperfusion is circulatory function. Arterial flow at this time may be critical for bile secretion. Porcine livers were isolated, maintained at 4° for 2 h and connected in an extracorporeal circuit to an anesthetized normal pig. The extracorporeal livers were perfused either by both the hepatic artery and portal vein (dual) or by the portal vein alone (single). Incremental doses of sodium taurocholate were infused into the portal vein of both the dual and single perfused livers, and the bile secretion was compared. Most endogenous bile acids are lost during hepatic isolation. After supplementation, the biliary secretion of phosphatidyl choline and cholesterol was significantly better in the dual than single vessel-perfused livers; however, no difference was seen in bilirubin output. Single perfused livers were completely unable to increase biliary cholesterol in response to bile acid. The dependence of bile cholesterol secretion on arterial flow indicates the importance of this flow to the detoxification of compounds dependent on phosphatidyl choline transport during early transplantation. [source] Doppler studies of the ovarian venous blood flow in the diagnosis of adnexal torsionJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2009Khatib Nizar MD Abstract Purpose. To evaluate the role of ovarian Doppler studies in diagnosing adnexal torsion. Methods. We included in that study all patients who had an adnexal mass with clinical symptoms of intermittent lower abdominal pain and were hospitalized for at least 48 hours of observation. Our protocol included: measurements of the size of the adnexal mass, presence or absence of ovarian edema, presence or absence of adnexal vascularity, presence or absence of ovarian artery flow, presence or absence of ovarian venous flow, pattern of ovarian venous flow. The ovarian artery and vein were sampled just above and lateral to the adnexa. Sensitivity, specificity, and positive and negative predictive values in the diagnosis of adnexal torsion were calculated for each of the gray-scale and Doppler sonographic (US) findings. Results. One hundred and ninety-nine patients presented with adnexal mass and intermittent lower abdominal pain. Sensitivity and specificity of tissue edema, absence of intra-ovarian vascularity, absence of arterial flow, and absence or abnormal venous flow in the diagnosis of adnexal torsion were: 21% and 100%, 52% and 91%, 76% and 99%, and 100% and 97%, respectively. All patients with adnexal torsion had absent flow or abnormal flow pattern in the ovarian vein. In 13 patients, the only abnormality was absent or abnormal ovarian venous flow with normal gray-scale US appearance and normal arterial blood flow. Of these 13 patients, 8 (62%) had adnexal torsion or subtorsion. Conclusion. Abnormal ovarian venous flow may be the only abnormal US sign observed during the early stage of adnexal torsion. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2009 [source] Hepatic arterial flow becomes the primary supply of sinusoids following partial portal vein ligation in ratsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2006Yukihiro Yokoyama Abstract Background and Aim:, Partial portal vein ligation (PPVL) is a commonly used procedure to induce prehepatic portal hypertension in animal models. The aim of this study was to test the hypothesis that the hepatic arterial flow becomes the primary source feeding the sinusoids in the liver after PPVL. Methods:, Sprague,Dawley rats underwent either sham operation or partial portal vein ligation (PPVL). The number of vessels in the liver at 2 weeks postoperatively was determined by factor VIII immunolocalization and the gene expression of angiogenic factors was assessed by RT-PCR. The total hepatic arterial supply to the liver was measured using the fluorescent microsphere injection technique. To further test the hypothesis, two additional groups of rats underwent hepatic artery ligation (HAL) or PPVL plus HAL (PPHAL). The integrity of hepatic microcirculation was then evaluated in all four groups by intravital microscopy. Results:, At 2 weeks after operation, the number of vessels detected by factor VIII staining was significantly higher in PPVL compared to sham. Densitometric analysis of RT-PCR bands revealed a significant increase of vascular endothelial growth factor gene expression in PPVL compared to sham. Arterial flow to the liver measured by fluorescent microspheres was increased by 190% in PPVL compared to sham. When all four groups were compared, no prominent histological abnormality was observed in sham, HAL, and PPVL groups; however, PPHAL livers showed focal necrosis and inflammatory cell infiltration around the portal triads. Additionally, only the PPHAL livers showed a decreased sinusoidal diameter and significantly lower perfusion index (PPHAL 42.9 ± 6.1; sham 85.7 ± 7.0, PPVL 80.2 ± 6.5, HAL 70.9 ± 4.5). Conclusions:, These results suggest that the hepatic artery flow becomes the primary source for the blood supply of sinusoids and the compensatory change in the hepatic arterial system plays a critical role in maintaining microcirculatory perfusion following the restriction of the portal vein flow by PPVL. [source] Chronological analysis of physiological T2* signal change in the cerebrum during breath holdingJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2001Kazuyoshi Nakada MD Abstract The purpose of this study was to examine which physiological factors affect cerebral T2* signal intensity (SI) during breath holding (BH) (apnea after inspiration and breathing after expiration) in normal volunteers. We examined SI changes caused by anoxic gas inhalation, by respiratory movements, and by BH. High-speed echo planar images (EPI) showed changes in SI that could be divided into five phases. Reports indicate that SI changes induced by BH are due to the effects on the magnetic susceptibility of deoxygenated hemoglobin (deoxyhemoglobin (dHb)) and to hypercapnia, but these reports could not fully explain the observed five phases. In addition to deoxyhemoglobin susceptibility and hypercapnia, we found that respiratory movements play a third critical role in modifying SI by affecting blood flow into the region of interest (ROI), as judged from right carotid artery flow. Consequently, we propose that the physiological SI changes induced by BH are derived from blood oxygenation, hypercapnia, and respiratory movements. J. Magn. Reson. Imaging 2001;13:344,351. © 2001 Wiley-Liss, Inc. [source] Adenosine restores the hepatic artery buffer response and improves survival in a porcine model of small-for-size syndrome,LIVER TRANSPLANTATION, Issue 11 2009Dympna M. Kelly The aim of the study is to define the role of the HABR in the pathophysiology of the SFS liver graft and to demonstrate that restoration of hepatic artery flow (HAF) has a significant impact on outcome and improves survival. Nine pigs received partial liver allografts of 60% liver volume, Group 1; 8 animals received 20% LV grafts, Group 2; 9 animals received 20% LV grafts with adenosine infusion, Group 3. HAF and portal vein flow (PVF) were recorded at 10 min, 60 min and 90 min post reperfusion, on POD 3 and POD 7 in Group 1, and daily in Group 2 and 3 up to POD 14. Baseline HAF and PVF (ml/100g/min) were 29 ± 12 (mean ± SD) and 74 ± 8 respectively, with 28% of total liver blood flow (TLBF) from the HA and 72% from the PV. PVF peaked at 10 mins in all groups, increasing by a factor of 3.8 in the 20% group compared to an increase of 1.9 in the 60% group. By POD 7-14 PVF rates approached baseline values in all groups. The HABR was intact immediately following reperfusion in all groups with a reciprocal decrease in HAF corresponding to the peak PVF at 10 min. However in the 20% group HAF decreased to 12 ± 8 ml/100 g/min at 90 min and remained low out to POD 7-14 despite restoration of normal PVF rates. Histopathology confirmed evidence of HA vasospasm and its consequences, cholestasis, centrilobular necrosis and biliary ischemia in Group 2. HA infusion of adenosine significantly improved HAF (p < .0001), reversed pathological changes and significantly improved survival (p = .05). An impaired HABR is important in the pathophysiology of the SFSS. Reversal of the vasospasm significantly improves outcome. Liver Transpl 15:1448,1457, 2009. © 2009 AASLD. [source] Rat liver transplantation for total vascular reconstruction, using a suture methodMICROSURGERY, Issue 5 2003Seiichiro Inoue M.D. We developed a novel protocol for rat orthotopic liver transplantation (OLT), using a suture method to establish hepatic artery flow. After determining that early inferior vena cava (IVC) unclamping maintained better circulation compared with the portal vein (PV) using porto-systemic shunted recipients, we developed a rat OLT model with total vascular reconstruction using a suture method. After connecting the suprahepatic IVC, the infrahepatic IVC was anastomosed, using a running suture method. IVC circulation was established immediately. The PV was anastomosed without intestinal congestion, using porto-systemic shunted recipients. The aortic conduit, including the donor celiac and hepatic artery, was anastomosed to the recipient abdominal aorta end-to-side. Eight of 11 OLT cases (72.7%) survived indefinitely. Biliary connection was achieved using a one-stent method. Three cases died 3,5 days postoperatively. Hepatic angiography showed good patency. The graft liver was histologically normal in long-surviving rats. © 2003 Wiley-Liss, Inc. MICROSURGERY 23:470,475 2003 [source] Routine assessment of coeliac axis and renal artery flow is not feasible with transoesophageal echocardiographyANAESTHESIA, Issue 1 2009C. F. Royse No abstract is available for this article. [source] The iliac bifurcation device for endovascular iliac aneurysm repair: indications, deployment options and results at 1-year follow-up of 25 casesANZ JOURNAL OF SURGERY, Issue 11 2009Ravi L. Huilgol Abstract Background:, The iliac bifurcation device (William A Cook Australia, Brisbane, QLD, Australia) is a new endovascular device for iliac aneurysm repair. We review the indications for use, device characteristics, deployment options and the results of our case series. Methods:, The most common indication for deployment is endovascular aortic aneurysm repair (EVAR) with common iliac aneurysm repair. The standard deployment sequence can be adapted to increase the utility of the device. Data were collected prospectively. Follow-up was performed with plain X-ray, ultrasound and computed tomography (CT) scan. Results:, Between 2004 and 2007, 25 patients had their common iliac artery aneurysm repaired using the iliac bifurcation device. There were 23 male and 2 female patients. Median age was 75 years (range 60,85). The median follow-up was 12 months (range 1,38). Twenty-one procedures were combined with EVAR. The median abdominal aortic aneurysm diameter was 60 mm (range 31,97), and the median common iliac artery aneurysm diameter was 37 mm (range 24,71). Technical success was achieved in 100% of cases. There were no acute branch vessel occlusions. There was one early type I endoleak (4%). There was one death (4%) in the 30-day period post-procedure. There was one late type I endoleak (4%). Conclusions:, The iliac bifurcation device achieves endovascular common iliac artery aneurysm repair with preservation of internal iliac artery flow. There are multiple different applications of the device and complementary deployment techniques. High rates of technical success and low rates of branch vessel occlusion are possible. [source] Prospective analysis of carotid artery flow in breast cancer patients treated with supraclavicular irradiation 8 or more years previously,CANCER, Issue 2 2008No increase in ipsilateral carotid stenosis after radiation noted Abstract BACKGROUND. To the authors' knowledge, the effects of supraclavicular fossa radiation on the carotid artery are not well described. In the current study, the authors performed a prospective study to examine the long-term risk of carotid artery stenosis after supraclavicular irradiation for breast cancer. METHODS. A total of 46 breast cancer patients who were treated with adjuvant radiation to the supraclavicular fossa with >8 years of follow-up underwent bilateral Doppler imaging of the carotid artery. Two independent cardiologists interpreted each ultrasound study with no knowledge of which side was treated. RESULTS. The median follow-up from the date of diagnosis was 14.6 years and the mean patient age at the time of ultrasound was 55 years. The median prescribed dose to the supraclavicular fossa was 50 grays. Four patients were found to have clinically relevant, asymptomatic carotid stenosis, for which a cardiology referral was necessary. Only 1 of these 4 patients had stenosis involving the irradiated carotid artery only; 1 patient had bilateral stenosis and 2 patients had only contralateral stenosis. There was no difference noted with regard to isolated ipsilateral versus contralateral medial intimal thickening of the carotid artery (5 patients vs 6 patients, respectively). Furthermore, there were no differences noted with regard to ipsilateral versus contralateral peak systolic flow in the internal (83.5 vs 85.6 cm/seconds; P = .522 by the Student t test and P = .871 by the signed rank test) or common (74.4 vs 77.0 cm/seconds; P = .462 by the Student t test and P = .246 by the signed rank test) carotid artery. CONCLUSIONS. In this prospective study of breast cancer patients with long follow-up, there was no evidence of late, clinically relevant stenosis, increased intimal thickening, or increased peak systolic carotid artery flow secondary to supraclavicular irradiation. Cancer 2008. © 2007 American Cancer Society. [source] Supraorbital cutaneous blood flow rate during carotid endarterectomyCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 6 2006Jens D. Hove Summary Background:, The supraorbital skin region is supplied by the supraorbital artery, which is a branch of the internal carotid artery. The supraorbital cutaneous blood flow rate may therefore be influenced by changes in the internal carotid artery flow during carotid endarterectomy. Methods:, The supraorbital cutaneous blood flow rate was measured by the application of heat to the skin and following the subsequent dissipation of the heat in seven patients undergoing carotid endarterectomy. At the same time, the oxygenation in the right and left frontal region was monitored by near-infrared spectroscopy (NIRS). Results:, During cross-clamping of the carotid artery, the ipsilateral NIRS-determined frontal oxygenation tended to decrease [67 ± 13% to 61 ± 11% (P = 0·06); contralateral 68 ± 11% to 66 ± 8%] as did the supraorbital cutaneous blood flow rate from 56 ± 23 to 44 ± 7 ml 100 g,1 min,1. With the opening of the external carotid artery, the NIRS-determined frontal oxygenation reversed to 66 ± 8% (P<0·05) on the ipsilateral side, with no significant change on the contralateral side and the supraorbital cutaneous blood flow rate increased to 53 ± 11 (P<0·05). Opening of the internal carotid artery did not significantly affect the NIRS (67 ± 8% and 69 ± 9%; ipsilateral, contralateral), but the supraorbital cutaneous blood flow rate increased to 88 ± 10 ml 100 g,1 min,1 (P<0·001). Conclusion:, Cross-clamping of the internal carotid artery affects the supraorbital cutaneous blood flow rate as well as the frontal lobe oxygenation. [source] | |||||||||||||||||||