Portal hemodynamics in chronic portal-systemic encephalopathy

International Nuclear Information System (INIS)

Takashi, Motohide; Igarashi, Masahiko; Hino, Shinichi; Takayasu, Kenichi; Goto, Nobuaki; Musha, Hirotaka; Ohnishi, Kunihiko; Okuda, Kunio

1985-01-01

A portal hemodynamic study was made in 7 consecutive patients with chronic portal-systemic encephalopathy by percutaneous transhepatic catheterization of the portal vein and injecting contrast medium into the superior mesenteric vein or by superior mesenteric arterial portography in comparison with patients without encephalopathy studied by percutaneous catheterization of these veins. It is suggested that chronic portal-systemic encephalopathy is a result of a large collateral route shunting a large proportion of the superior mesenteric venous blood into systemic circulation, and that development of such collaterals precludes formation of large esophageal varices. (Auth.)

[To evaluate the role of OLT on splenomegaly of portal hypertension by the radiological changes of splenic morphology and collaterals].

Science.gov (United States)

Liang, Ying-ying; Wang, Jin; Shan, Hong; Yan, Rong-hua; Hu, Bing; Jiang, Zai-bo; He, Bing-jun; Liu, Jing-jing; Ren, Ling-lan; Shao, Shuo

2012-11-20

To explore the effect of orthotopic liver transplantation (OLT) on portal hypertension by observing the radiological changes of splenic volume and collaterals before and after OLT. In our hospital 56 patients performing OLT due to cirrhosis, portal hypertension and splenomegaly were classified into five groups according to their following-up time: A (≤3 months), B (>3-6 months), C (>6-12 months), D (>12-24 months), and E (>24 months). Twenty health people were chose as control group (F). The splenic width, thickness, length, volume, diameter of portal and splenic vein and collaterals were measured and observed in every patient of six groups before and after OLT respectively. After OLT, the splenic volume decreased by 25.4%, 27.8%, 21.9%, 25.2%, 27.7% in five groups respectively, which was still larger than the normal group (POLT. The opened umbilical vein disappeared and the retroperitoneal varices persisted in five cases after OLT. Splenomegaly and opened collaterals can be relieved by OLT effectively. The splenic volume didn't change obviously until it decreased by 25% in the three months after OLT. Gastroesophageal varices can be removed in most of patients after OLT. The splenomegaly could last paralled with the splenic vein and retroperitoneal varices after OLT. After OLT, correct disposal of splenic and collateral changes could improve the success rate and the long-term treatment effect of OLT.

Portal Vein Stenting for Portal Biliopathy with Jaundice

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Hyun, Dongho, E-mail: mesentery@naver.com; Park, Kwang Bo, E-mail: kbjh.park@samsung.com [Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center (Korea, Republic of); Lim, Seong Joo [Konyang University, Department of Radiology, College of Medicine, Konyang University Hospital (Korea, Republic of); Hwang, Jin Ho [Hallym University Sacred Heart Hospital, Department of Radiology (Korea, Republic of); Sinn, Dong Hyun [Sungkyunkwan University School of Medicine, Department of Medicine, Samsung Medical Center (Korea, Republic of)

2016-04-15

Portal biliopathy refers to obstruction of the bile duct by dilated peri- or para-ductal collateral channels following the main portal vein occlusion from various causes. Surgical shunt operation or endoscopic treatment has been reported. Herein, we report a case of portal biliopathy that was successfully treated by interventional portal vein recanalization.

Portosystemic collateral circulation in the falciform ligament: evaluation with three dimensional dynamic contrast enhanced MR angiography in patients with portal hypertension

International Nuclear Information System (INIS)

Wu Zhuo; Liang Biling; Li Yong; Zhong Jinglian; Ye Ruixin; Zhang Rong

2009-01-01

Objective: The purpose of our study was to investigate three dimensional dynamic contrast enhanced MR angiography(3D DCE MRA) in the detection of portosystemic collateral circulation in the falciform ligament in patients with portal hypertension. Methods: From April 2003 to July 2008, 53 portal hypertension patients with varices in the falciform ligament were evaluated with 3D DCE MRA. Two radiologists independently assessed the number, diameter, location and drainages of the portosystemic collateral circulation in the falciform ligament according to the information on the 3D DCE MRA. Results: The veins in the falciform ligament were classified into the superior and inferior groups, and both groups arise from the left trunk of the portal vein. In our study, the number of varices detected on 3D DCE MRA images varied from 1 to 3, and the diameters of these vessels varied from 0.4 to 2.6 cm. The inferior group consisted of paraumbilical/umbilical veins (47 cases), which flowed toward umbilicus and then drained upwards (n=16) including deep superior epigastric veins (n=7), superficial superior epigastric veins (n=9), downwards (n=40) including deep inferior epigastric veins (n=7), superficial inferior epigastric veins (n=33), or upwards and downwards at the same time (n=9). The superior group of vessels in the falciform ligament were directly anastomosed with the internal thoracic vessels (n=6). Conclusion: In patients with portal hypertension, 3D DCE MRA can optimally demonstrate the portosystemic collateral circulation in the falciform ligament, which includes the superior and inferior drainage groups. (authors)

Computed tomographic diagnosis for hepatofugal collaterals in portal hypertension. Comparative study of CT with percutaneous transhepatic portography

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Iida, Akihiko; Sano, Akira; Imanaka, Kazufumi; Nishizawa, Sadahiko; Sasai, Keisuke

1984-08-01

This paper deals with the diagnostic capability of CT scan for hepatofugal collaterals in 22 patients with portal hypertension. The patients studied were those who underwent percutaneous transhepatic portography (PTP) and CT scan within a short period. Each collateral vein demonstrated by PTP was classified into three grades according to its caliber (d): (1) Grade I, d<5mm, (2) Grade II, 5mmcollaterals on the CT images was analyzed comparatively. Most collaterals in Grade I failed to demonstrate on CT images, while Grade II and III well coincided with CT images, at the rate of 64% and 100% respectively. CT features of these vascular structures showed multiformity: rounded, ovoid comma-shaped, tubular or beaded, etc. To get an accurate diagnosis, each image must be analyzed together with the adjacent upper and lower ones on the fully-performed contrast enhancement technique. Image deterioration of CT was concerned with Partial Volume Phenomenon for small vessels, and motion artifacts produced by intestinal peristalses, cardiac beats and occasionally by difficulty of breath holding. In spite of such diagnostic Iimitation, CT scan provides much qualified images than conventional angiographic procedures in evaluating hepatofugal collaterals.

Doppler US evaluation of the hypertensive portal system

International Nuclear Information System (INIS)

Needleman, L.; Kurtz, A.B.; Bezzi, M.; Rifkin, M.D.; Pasto, M.E.; Pennell, R.G.; Baltarowich, O.H.; Goldberg, B.B.

1986-01-01

In patients with known portal hypertension, pulsed Doppler US was used for qualitative and directional evaluation of flow in the portal venous system and collateral vessels. Most patients had normal hepatopetal flow. Doppler US revealed the following abnormal blood flow patterns: hepatofugal portal flow, bidirectional portal flow, intrahepatic portal shunting, flow in portasystemic collaterals, and hepatic vein obstruction. Doppler US can provide important clinical information in the evaluation of portal hypertension

Radioisotopic splenoportography in pediatric patients with portal hypertension

International Nuclear Information System (INIS)

Ohshima, Koji; Miyamoto, Kazutoshi; Yokoyama, Yasuhiro; Kubo, Yoshihiko; Samejima, Natsuki

1990-01-01

Radioisotopic splenoportography (RI-splenoportography) was performed in 11 children (6 patients with biliary atresia, 3 with extrahepatic portal obstruction, 1 with congenital hepatic fibrosis and 1 with pediatric liver cirrhosis). Collateral pathways were found in 9 patients by RI-imaging, of whom 6 patients had ascending pathways alone, 1 had both ascending and descending pathways, and 2 had only descending pathways. Esophageal varices were found endoscopically in all 7 patients with ascending collateral pathways, but were not found in 2 patients with the descending collateral pathways alone or in 2 patients without collateral pathway images. Endoscopic injection sclerotherapy (EST) was performed in one patient with biliary atresia who had had episodes of rupture of esophageal varices. Ascending collateral pathways were recognized by RI-splenoportography before EST, but they disappeared completely after three sessions of EST. In two patients with extrahepatic portal obstruction and a patient with congenital hepatic fibrosis who underwent meso-caval shunt operations, shunt patency and disappearance of ascending collateral pathways were proved clearly by RI-splenoportography after the operations. RI-splenoportography is very useful for investigation of portal venous collateral circulation in portal hypertension or for confirming patency of portosystemic shunts. (author)

Intrahepatic Left to Right Portoportal Venous Collateral Vascular Formation in Patients Undergoing Right Portal Vein Ligation

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Lienden, K. P. van, E-mail: k.p.vanlienden@amc.uva.nl [Academic Medical Center, University of Amsterdam, Department of Interventional Radiology (Netherlands); Hoekstra, L. T. [Academic Medical Center, University of Amsterdam, Department of Surgery (Netherlands); Bennink, R. J. [Academic Medical Center, University of Amsterdam, Department of Nuclear Medicine (Netherlands); Gulik, T. M. van [Academic Medical Center, University of Amsterdam, Department of Surgery (Netherlands)

2013-12-15

Purpose: We investigated intrahepatic vascular changes in patients undergoing right portal vein ligation (PVL) or portal vein embolization (PVE) in conjunction with the ensuing hypertrophic response and function of the left liver lobe. Methods: Between December 2008 and October 2011, 7 patients underwent right PVL and 14 patients PVE. Computed tomographic (CT) volumetry to assess future remnant liver (FRL) and functional hepatobiliary scintigraphy were performed in all patients before and 3 weeks after portal vein occlusion. In 18 patients an intraoperative portography was performed to assess perfusion through the occluded portal branches. Results: In all patients after initially successful PVL, reperfused portal veins were observed on CT scan 3 weeks after portal occlusion. This was confirmed in all cases during intraoperative portography. Intrahepatic portoportal collaterals were identified in all patients in the PVL group and in one patient in the PVE group. In all other PVE patients, complete occlusion of the embolized portal branches was observed on CT scan and on intraoperative portography. The median increase of FRL volume after PVE was 41.6 % (range 10-305 %), and after PVL was only 8.1 % (range 0-102 %) (p = 0.179). There were no differences in FRL function between both groups. Conclusion: Preoperative PVE and PVL are both methods to induce hypertrophy of the FRL in anticipation of major liver resection. Compared to PVE, PVL seems less efficient in inducing hypertrophy of the nonoccluded left lobe. This could be caused by the formation of intrahepatic portoportal neocollateral vessels, through which the ligated portal branches are reperfused within 3 weeks.

Radioisotopic splenoportography in patients with portal hypertension

International Nuclear Information System (INIS)

Samejima, Natsuki; Ikeda, Koichiro; Yokoyama, Yasuhiro; Hirata, Satoru

1989-01-01

Radio-isotopic splenoportography was performed by injecting 99m TcO 4 - into the spleens of 46 patients with portal hypertension and 14 patients with various disorders not having portal hypertension. No collateral circulation was demonstrated in the 14 patients without portal hypertension whereas some RI-images of portosystemic collaterals were found in 40 (87.0 per cent) of the 46 patients with portal hypertension. Collaterals were divided into an ascending group and a descending group, the appearance rate of ascending collaterals being 80.4 per cent and that of descending collaterals, 41.3 per cent. There were 3 image patterns in the ascending group, namely, an AZ-pattern in which the azygos vein was demonstrated; a SC-pattern in which the RI-bolus ascended along the esophagus to the neck and the subclavian vein; and an EG-pattern which showed stagnation of the RI-bolus in the esophagogastric region. There were 4 patterns in the descending group, namely; a pattern of gastro-renal caval shunt (GR-pattern); reverse flow patterns into the umbilical or paraumbilical veins (UV-pattern); into the superior mesenteric vein (SMV-pattern); and into the inferior mesenteric vein (IMV-pattern). The appearance of the EG-pattern was seen most frequently (74.4 per cent). The usefulness of this method for surveying the collateral circulation in portal hypertension, estimating the risk of esophageal variceal bleeding and evaluating its treatments, was suggested by the results of this study. (author)

[Predictive value of ultrasonography in portal hypertension].

Science.gov (United States)

Moreno, E; Torres, P; Trejo, C; Barra Ostoni, V; Ortega, C; Römer, H

1991-01-01

Portal hypertension is a common pathology in childhood and one of its most common causes is cavernomatosis of the portal vein. This obstruction causes hemodynamic changes which lead to splenomegaly and collateral circulation. Esophageal varices are one of the most important sequelae, which endanger the patient's life because of a bleeding tendency. Ecosonography helps to detect the thickening of the lesser omentum vis a vis the aortic diameter, caused by the collateral circulation. We studied 15 children presenting with portal hypertension resulting from portal vein cavernomatosis; we performed an upper GI endoscopy and abdominal ecosonography. The endoscopy revealed grade II esophageal varices in 20% of cases, the remaining 80% had grade III and grade IV. Ecosonography revealed an increased lesser omentum/aorta ratio in children with portal hypertension, compared to controls (p portal hypertension.

The portal vein in children: radiological review of congenital anomalies and acquired abnormalities

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Corness, Jonathan A.G.; McHugh, Kieran; Roebuck, Derek J. [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Taylor, Andrew M. [Institute of Child Health, Cardiothoracic Unit, London (United Kingdom)

2006-02-01

A variety of portal vein anomalies that occur in children can be identified by US, CT, MRI and portal venography. Although these abnormalities can also occur in adults, there are certain pathological processes and aberrations within the portal system that are specific to children. Knowledge of the embryology and anatomy of the portal vein is of benefit in the understanding of these anomalies. Identifying deviations from normal portal architecture is important in the work-up for surgery such as liver transplantation, and prior to interventional procedures such as stent placement or embolization. The aim of this paper is to summarize the various types of congenital and acquired portal vein abnormalities that occur in children, describe their radiological features and provide images to demonstrate the differences from normal portal venous anatomy. (orig.)

The portal vein in children: radiological review of congenital anomalies and acquired abnormalities

International Nuclear Information System (INIS)

Corness, Jonathan A.G.; McHugh, Kieran; Roebuck, Derek J.; Taylor, Andrew M.

2006-01-01

A variety of portal vein anomalies that occur in children can be identified by US, CT, MRI and portal venography. Although these abnormalities can also occur in adults, there are certain pathological processes and aberrations within the portal system that are specific to children. Knowledge of the embryology and anatomy of the portal vein is of benefit in the understanding of these anomalies. Identifying deviations from normal portal architecture is important in the work-up for surgery such as liver transplantation, and prior to interventional procedures such as stent placement or embolization. The aim of this paper is to summarize the various types of congenital and acquired portal vein abnormalities that occur in children, describe their radiological features and provide images to demonstrate the differences from normal portal venous anatomy. (orig.)

Extrahepatic angiogenesis hinders recovery of portal hypertension and collaterals in rats with cirrhosis resolution.

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Hsu, Shao-Jung; Tsai, Ming-Hung; Chang, Ching-Chih; Hsieh, Yu-Hsin; Huang, Hui-Chun; Lee, Fa-Yauh; Chuang, Chiao-Ling; Hou, Ming-Chih; Lee, Shou-Dong

2018-03-30

Liver cirrhosis is characterized by portal hypertension. However, the alteration of portal hypertension-related derangements during cirrhosis resolution is not well known. The present study aimed to establish animal models with cirrhosis resolution and to investigate the relevant changes during this process. Male Sprague-Dawley rats were applied. In reverse thioacetamide (rTAA) model, rats were randomly allocated into four groups with control, thioacetamide (TAA) cirrhosis and rTAA groups that discontinued TAA for 4 or 8 weeks after cirrhosis induction. In reverse bile duct ligation (rBDL) model, rats received choledochoduodenal shunt surgery upon the establishment of cirrhosis and 4, 8, or 16 weeks were allowed after the surgery. At the end, portal hypertension-related parameters were evaluated. Cirrhosis resolution was observed in rTAA groups. Portal pressure (PP) decreased after cirrhosis resolution but remained higher than control group (control, TAA, rTAA4, rTAA8 (mmHg): 5.4 ± 0.3, 12.9 ± 0.3, 8.6 ± 0.4, 7.6 ± 0.6). Further survey found the increased splanchnic blood flow did not reduce during cirrhosis resolution. The extrahepatic pathological angiogenesis was not ameliorated (% of mesenteric window area: 1.2 ± 0.3, 7.3 ± 1.1, 8.3 ± 1.0, 11.3 ± 2.7). In collateral system, the shunting degree reduced while the vessels structure remained. The vascular contractility of all systems and nitric oxide (NO) production were normalized. In rBDL series, PP decreased in rBDL16 groups but the extrahepatic angiogenesis persisted. In conclusion, cirrhosis resolution attenuates but not completely normalizes portal hypertension because of persistently high splanchnic inflow and angiogenesis. In clinical setting, vascular complications such as varices could persist after cirrhosis resolution and further investigation to define the follow-up and treatment strategies is anticipated. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical

An analysis of splenoportographic findings in portal hypertension

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Jung, Eun Mi; Moon, Sook Ran; Kim, Han Suk [National Medical Center, Seoul (Korea, Republic of); Park, Soo Soung [College of Medicine, Chung Ang University, Seoul (Korea, Republic of)

1983-12-15

Splenoportography has been proved as a useful method for the evaluation of circulatory disturbances in portal hypertension. Authors analyzed the various aspects of these disturbance on splenoportography in 22 cases that was performed under the clinical suspicion of portal hypertension during recent 6 years, from May, 1976 to July 1982 at the Department of Radiology, National Medical Center. The results were as follows: 1. Liver cirrhosis was the most frequent cause of intrahepatic obstruction type in portal hypertension (86%). 2. The portal pressure was more than 400 mmH{sub 2}0 in 67% of the cases (range; 300-540 mmH{sub 2}0). 3. In the majority of the cases, the higher the portal pressure was, the more dilated splenic and portal veins were. The diameter of portal vein was more than 15 mm in 79%, more than 21 mm in 47% of the cases (range; 10-26 mm). The diameter of splenic vein was more than 15 mm in 48% of the cases (range; 7-23 mm). Especially the diameter of splenic vein was larger than that of portal vein in 20% of the cases. 4. There was no definite correlation between the development of collateral circulation and the diameter of splenic and portal veins. 5. The filling of collateral circulation was definite sign of portal hypertension, though not regular. In portal hypertension, the collateral circulation was formed via coronary vein (91%), short gastric vein (64%), inferior mesenteric vein (36%). 6. Splenic-hilum time was delayed in 64% of the cases. Intrahepatic portal vein emptying time was more than 6 seconds in all the cases. 7. Most of the cases (91%) could be diagnosed as portal hypertension with vasculogram and hepatogram.

An analysis of splenoportographic findings in portal hypertension

International Nuclear Information System (INIS)

Jung, Eun Mi; Moon, Sook Ran; Kim, Han Suk; Park, Soo Soung

1983-01-01

Splenoportography has been proved as a useful method for the evaluation of circulatory disturbances in portal hypertension. Authors analyzed the various aspects of these disturbance on splenoportography in 22 cases that was performed under the clinical suspicion of portal hypertension during recent 6 years, from May, 1976 to July 1982 at the Department of Radiology, National Medical Center. The results were as follows: 1. Liver cirrhosis was the most frequent cause of intrahepatic obstruction type in portal hypertension (86%). 2. The portal pressure was more than 400 mmH 2 0 in 67% of the cases (range; 300-540 mmH 2 0). 3. In the majority of the cases, the higher the portal pressure was, the more dilated splenic and portal veins were. The diameter of portal vein was more than 15 mm in 79%, more than 21 mm in 47% of the cases (range; 10-26 mm). The diameter of splenic vein was more than 15 mm in 48% of the cases (range; 7-23 mm). Especially the diameter of splenic vein was larger than that of portal vein in 20% of the cases. 4. There was no definite correlation between the development of collateral circulation and the diameter of splenic and portal veins. 5. The filling of collateral circulation was definite sign of portal hypertension, though not regular. In portal hypertension, the collateral circulation was formed via coronary vein (91%), short gastric vein (64%), inferior mesenteric vein (36%). 6. Splenic-hilum time was delayed in 64% of the cases. Intrahepatic portal vein emptying time was more than 6 seconds in all the cases. 7. Most of the cases (91%) could be diagnosed as portal hypertension with vasculogram and hepatogram

Detection of cavernous transformation of the portal vein by contrast-enhanced ultrasound.

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Hwang, Misun; Thimm, Matthew A; Guerrerio, Anthony L

2018-06-01

Cavernous transformation of the portal vein can be missed on color Doppler exam or arterial phase cross-sectional imaging due to their slow flow and delayed enhancement. Contrast-enhanced ultrasound (CEUS) offers many advantages over other imaging techniques and can be used to successfully detect cavernous transformations of the portal vein. A 10-month-old female was followed for repeat episodes of hematemesis. Computed tomography angiography (CTA) and magnetic resonance arteriogram (MRA) and portal venography were performed. Color Doppler exam of the portal vein was performed followed by administration of Lumason, a microbubble US contrast agent. Magnetic resonance arteriogram, CTA, and color Doppler exam at the time of initial presentation was unremarkable without obvious vascular malformation within the limits of motion degraded exam. At 8-month follow-up, esophagogastroduodenoscopy revealed a vascular malformation in the distal esophagus which was sclerosed. At 6 month after sclerosis of the lesion, portal venography revealed occlusion of the portal vein with extensive collateralization. Color Doppler revealed subtle hyperarterialization and periportal collaterals. CEUS following color Doppler exam demonstrated extensive enhancement of periportal collaterals. Repeat color Doppler after contrast administration demonstrated extensive Doppler signal in the collateral vessels, suggestive of cavernous transformation. We describe a case of cavernous transformation of the portal vein missed on initial color Doppler, CTA and MRA, but detected with contrast-enhanced ultrasound technique.

Embolization of nonvariceal portosystemic collaterals in transjugular intrahepatic portosystemic shunts

International Nuclear Information System (INIS)

Bilbao, Jose Ignacio; Arias, Mercedes; Longo, Jesus Maria; Alejandre, Pedro Luis; Betes, Maria Teresa; Elizalde, Arlette Maria

1997-01-01

Percutaneous embolization of large portosystemic collaterals was performed in three patients following placement of a transjugular intrahepatic portosystemic shunt in order to improve hepatopetal portal flow. Improved hepatic portal perfusion was achieved in these cases, thereby theoretically reducing the risk of chronic hepatic encephalopathy

Diagnosis of hepatic encephalopathy with magentic resonance imaging; With special reference to portal system encephalopathy

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Inoue, Etsuo; Narumi, Yoshifumi; Kadota, Tsuyoshi; Fujita, Makoto; Kuriyama, Keiko; Kuroda, Chikazumi (Osaka Prefectural Center for Adult Diseases (Japan))

1993-01-01

Cranial magnetic resonance (MR) images were examined in 16 patients with liver cirrhosis. The findings of MR imaging were correlated with portal-systemic collateral vessel shown on angiograms. In 9 of 16 patients, basal ganglia was hyperintense compared with white matter on T1-weighted images. These 9 patients had portal-systemic collateral vessel 10 mm or more in diameter that was suppied by superior mesenteric vein (SMV), and 4 of the 9 patients had portal-systemic encephalopathy on angiograms. In the remaining 7 patients, no hyperintense lesions were seen in basal ganglia relative to white matter on T1-weighted images; angiography revealed that 2 patients had portal-systemic collateral vessel that was supplied by SMV but was 5 mm or less in diameter, 3 had bood supplies from splenic vein, and 2 had no collateral vessel. There was no change in signal intensity on T2-weighted images. In conclusion, a large portal-systemic collateral vessel supplied by SMV may be shown as a high intensity lesion in basal ganglia, thus making it possible to diagnose hepatic encephalopathy even if there was no psychoneurologic symptoms or signs. (N.K.).

Evaluation of portal hypertension by MR portography

International Nuclear Information System (INIS)

Nagaoka, Shirou; Hagiwara, Masaru; Imanisi, Yosimasa

1997-01-01

Seventy-eight examinations of MR portography were totally performed in 24 controls and 33 patients with esophageal varices. Portal vein, SMV, hepatic vein, and IVC were entirely depicted in 21, 24, 22, and 24, respectively, of the 24 controls. As to intrahepatic upward branches of portal vein in the right lobe of the liver, the 4th branch was at least depicted in all of the 24. Although the portal vein trunk and SMV were entirely depicted in all of the 8 patients without treatment and liver dysfunction of Child A, there was no depiction of them in 1 of the 8 patients with liver dysfunction of Child B, and 1 of 5 patients with liver dysfunction of Child C. The 4th upward branch of portal vein in the right lobe of the liver was depicted in none of the 33 patients. Besides, none of the intrahepatic portal branches were depicted in 1 of 8 patients without treatment and liver dysfunction of Child B, and 1 of the 5 patients without treatment and liver dysfunction of Child C. There was a significant difference of depicted terminal upward branch of portal vein between the controls and patients without any treatment. In the patients without any significant difference of depicted terminal upward branch of portal vein was also present between Child's classification A and Child's classification B and C. Gastric coronary vein varices were detected by MR portography is 18 of 19 patients without treatment on the esophageal varices, and paraesophageal/esophageal varices were also depicted by MR portography in 13 of the 19. The collaterals were depicted by MR portography in all of the 6 patients with recurrent collaterals after Hassab's operation or splenectomy. MR portography was able to depict flow in trunk branches and collaterals of the portal vein system in a physiological state. (K.H.)

Evaluation of portal hypertension by MR portography

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Nagaoka, Shirou; Hagiwara, Masaru; Imanisi, Yosimasa [St. Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

1997-02-01

Seventy-eight examinations of MR portography were totally performed in 24 controls and 33 patients with esophageal varices. Portal vein, SMV, hepatic vein, and IVC were entirely depicted in 21, 24, 22, and 24, respectively, of the 24 controls. As to intrahepatic upward branches of portal vein in the right lobe of the liver, the 4th branch was at least depicted in all of the 24. Although the portal vein trunk and SMV were entirely depicted in all of the 8 patients without treatment and liver dysfunction of Child A, there was no depiction of them in 1 of the 8 patients with liver dysfunction of Child B, and 1 of 5 patients with liver dysfunction of Child C. The 4th upward branch of portal vein in the right lobe of the liver was depicted in none of the 33 patients. Besides, none of the intrahepatic portal branches were depicted in 1 of 8 patients without treatment and liver dysfunction of Child B, and 1 of the 5 patients without treatment and liver dysfunction of Child C. There was a significant difference of depicted terminal upward branch of portal vein between the controls and patients without any treatment. In the patients without any significant difference of depicted terminal upward branch of portal vein was also present between Child`s classification A and Child`s classification B and C. Gastric coronary vein varices were detected by MR portography is 18 of 19 patients without treatment on the esophageal varices, and paraesophageal/esophageal varices were also depicted by MR portography in 13 of the 19. The collaterals were depicted by MR portography in all of the 6 patients with recurrent collaterals after Hassab`s operation or splenectomy. MR portography was able to depict flow in trunk branches and collaterals of the portal vein system in a physiological state. (K.H.)

Hepatic angiography: Portal hypertension

International Nuclear Information System (INIS)

Oliver, T.W. Jr.; Sones, P.J. Jr.

1985-01-01

Portal hypertension is usually a manifestation of underlying hepatic parenchymal disease, although it may be secondary to portal or hepatic venous thrombosis and rarely to hyperdynamic portal states. Portal hypertension may present as encephalopathy, ascites, jaundice, hepatic failure, or catastrophic upper gastrointestinal hemorrhage. Radiologic investigation should include indirect or direct measurements of portal pressure, assessment of portal venous perfusion, visualization of collaterals, and demonstration of arterial and venous anatomy for potential shunt procedure. Following survival of initial variceal bleeding, the most effective procedure to prevent recurrent hemorrhage is a shunt to decompress the varices. The decision whether to intervene medically or surgically during the acute hemorrhagic episode as well as the type of shunt used to prevent future hemorrhage is the subject of continuing controversy

Endothelial dysfunction in the regulation of portal hypertension

Science.gov (United States)

Iwakiri, Yasuko

2013-01-01

Portal hypertension is caused by an increased intrahepatic resistance, a major consequence of cirrhosis. Endothelial dysfunction in liver sinusoidal endothelial cells (LSECs) decreases the production of vasodilators, such as nitric oxide (NO) and favors vasoconstriction. This contributes to an increased vascular resistance in the intrahepatic/sinusoidal microcirculation. Portal hypertension, once developed, causes endothelial cell (EC) dysfunction in the extrahepatic, i.e. splanchnic and systemic, circulation. Unlike LSEC dysfunction, EC dysfunction in the splanchnic and systemic circulation overproduces vasodilator molecules, leading to arterial vasodilatation. In addition, portal hypertension leads to the formation of portosystemic collateral vessels. Both arterial vasodilatation and portosystemic collateral vessel formation exacerbate portal hypertension by increasing the blood flow through the portal vein. Pathologic consequences, such as esophageal varices and ascites, result. While the sequence of pathological vascular events in cirrhosis and portal hypertension have been elucidated, the underlying cellular and molecular mechanisms causing EC dysfunctions are not yet fully understood. This review article summarizes the current cellular and molecular studies on EC dysfunctions found during the development of cirrhosis and portal hypertension with a focus on intra- and extrahepatic circulation. The article ends by discussing future directions of study for EC dysfunctions. PMID:21745318

Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy - Case report.

Science.gov (United States)

Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B

2014-12-01

62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.

The evaluation of three-dimensional dynamic contrast enhanced MR angiography in portal hypertension

International Nuclear Information System (INIS)

Wu Zhuo; Liang Biling; Liu Qingyu; Zhong Jinglian; Ye Ruixin; Ling Yunbiao; Ou Qingjia

2006-01-01

Objective: To evaluate the techniques of three-dimensional dynamic contrast enhanced MR angiography (3D DCE MRA)with normative timing of sequences, enhancive 3D slab thickness and subtraction in portosystemic collaterals. Methods: Before April 2003, 12 patients were performed with 75-90 mm of 3D slab thickness and 3-5 repeated sequences estimated by breath, after April 2003, 18 patients were performed with 150-180 mm of 3D slab thickness and 5 normative repeated sequences respectively at 0, 20, 40, 60 and 90 s. After subtracting selective arterial phase images from subsequent portal venous phase images, two radiologists assessed visualization of portal collaterals independently with a four - point scale for ranking of image quality in maximum intensity projection (MIP) images with and without subtraction. Results: Average scores for image quality in visualization of the portal vein with subtraction were significantly depressed compared with the scores without subtraction (2.53±0.49 versus 2.74±0.31, P<0.05). However, subtraction three dimension-maximum intensity projection (3D-MIP) gave superior visualization of portal collaterals compared with non-subtraction 3D-MIP(2.58±0.30 versus 1.63±0.50). A statistically significant difference (P<0.01) was found between the two groups of esophageal varices. Most of portosystemic shunts demonstrated in the same time as the portal vein at about 20s, but some of collaterals demonstrated in delay time. Conclusion: Subtraction 3D-MIP demonstrates portosystemic collaterals more clearly than non-subtraction; normative timing of sequences ensure against omitting varices displayed late, 3 D slab thickness provides details about paraumbilical vein and retroperitoneal collaterals. (authors)

Multidetector Computed Tomography Assessment in Biliary Atresia for the Diagnosis of Portosystemic Collaterals before Liver Transplant

International Nuclear Information System (INIS)

Cadavid A, Lina; Barber, Ignasi; Bueno, Javier

2011-01-01

Introduction: Chronic liver disease increases portal vein pressure and modifies splanchnic circulation. This is particularly significant in infants with biliary atresia. Large collaterals steal portal flow and increase the risk of post transplant portal vein thrombosis. Objective: to describe different types of portosystemic collaterals prior to liver transplantation with low-dose multidetector CT (MDCT) in patients with biliary atresia. Material and methods: 13 patients with severe liver dysfunction due to biliary atresia underwent low-dose 64-MDCT before liver transplantation (effective tube current ranged from 20 to 120 mAs according to weight, with a kilo voltage of 80-120 for all CT). Hepatic arterial and portal venous phases were performed after IV contrast administration [1.5-2 ml/kg]. The mean age of the study group was1 year (range, 4 months to 3.6 years). Two radiologists reviewed the CT images to determine the grade and types of the portosystemic collaterals. Results: A total of 16 CT scans were obtained.the most common portosystemic collaterals found were esophageal (11), gastric submucosal (8), gastric adventitial (7, splenic (7), hemorrhoidal (10), mesenteric [dilated or tortuous branches of the inferior mesenteric vein (8)], retroperitoneal varices [gastro renal shunt (10), splenorenal shunt (4)] and dilated or tortuous left gastric vein (13). Conclusion: MDCT provides important information on venous system patency, presence of varices, and location of venous shunts in pediatric patients with biliary atresia going to liver transplant. in addition, it is critical to detect collaterals that are not evident on ultrasound in order to avoid the steal phenomenon that may lead to portal vein thrombosis and graft failure.

Quality study of portal images acquired by computed radiography and screen-film system under megavoltage ray

International Nuclear Information System (INIS)

Cao Guoquan; Jin Xiance; Wu Shixiu; Xie Congying; Zhang Li; Yu Jianyi; Li Yueqing

2007-01-01

Objective: To evaluate the quality of the portal images acquired by computed radiography (CR) system and conventional screen-film system, respectively. Methods: Imaging plates (IP) and X-ray films ora home-devised lead phantom with a leakage of 6.45% were acquired, and modulation transfer function (MTF) curves of the both images were measured using edge method. Portal images of 40 nasopharyngeal cancer patients were acquired by IP and screen-film system respectively. Two doctors with similar experience evaluated the damage degree of petrosal bone, the receiver operating characteristic (ROC) curve of CR images and general images were drawn according to two doctors evaluation results. Results: The identification frequency of CR system and screen-film system were 1.159 and 0.806 Lp/mm respectively. For doctor one, the area under ROC curve of CR images and general images were 0.802 and 0.742 respectively. For doctor two, the area under ROC curve of CR images and general images were 0.751 and 0.600 respectively. The MTF curve and ROC curve of CR are both better than those of screen-film system. Conclusion: The image quality of CR portal imaging is much better than that of screen-film system. The utility of CR in linear accelerator for portal imaging is promising in clinic. (authors)

Pathophysiology of Portal Hypertension and Its Clinical Links

Science.gov (United States)

Seo, Yeon Seok; Shah, Vijay H

2011-01-01

Portal hypertension is a major cause of morbidity and mortality in patients with liver cirrhosis. Intrahepatic vascular resistance due to architectural distortion and intrahepatic vasoconstriction, increased portal blood flow due to splanchnic vasodilatation, and development of collateral circulation have been considered as major factors for the development of portal hypertension. Recently, sinusoidal remodeling and angiogenesis have been focused as potential etiologic factors and various researchers have tried to improve portal hypertension by modulating these new targets. This article reviews potential new treatments in the context of portal hypertension pathophysiology concepts. PMID:25755320

Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

Science.gov (United States)

Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B.

2014-01-01

62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. Conclusion The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival. PMID:25568802

7 CFR 1779.90 - Disposition of acquired property.

Science.gov (United States)

2010-01-01

... Disposition of acquired property. (a) General. When the lender acquires title to the collateral and the final... 7 Agriculture 12 2010-01-01 2010-01-01 false Disposition of acquired property. 1779.90 Section... develop a plan to fully protect the collateral, and the lender must dispose of the collateral without...

[Portal thrombosis, common bile duct varices and cholestasis].

Science.gov (United States)

Agüera Arroyo, B; Pérez Durán, M A; Montero Alvarez, J L; Navarro Jarabo, J M; Calero Ayala, B; Miño Fugarolas, G

1996-03-01

A case of cholestasis in a young patient with portal cavernomatosis is reported. This clinical picture is very infrequent and appears as a consequence of extrinsic compression on the common bile duct due to which the derivative venous collaterals. There does not appear to be any relationship between the intensity of the morphologic alteration of the biliary tract and the level of portal hypertension and the degree of extrahepatic obstruction. Diagnosis was fundamentally achieved by arteriography and retrograde cholangiography with differential diagnosis with the previously mentioned diseases being required. Chronic cholestasis advises derivative surgery in which difficulties may be found due to the presence of thick collaterals in the hepatic pedicle as occurred in this patient.

Visualization of portal venous system by single photon emission CT

Energy Technology Data Exchange (ETDEWEB)

Kashiwagi, T; Ikawa, T; Azuma, M; Matsuda, H; Yoshioka, H; Mitsutani, N; Koizumi, T

1987-03-01

Single photon emission CT (SPECT) was performed for the intra-abdominal blood pool with /sup 99m/Tc autologous red blood cells (RBC) in 15 patients with liver cirrhosis. Twenty mCi of /sup 99m/Tc-RBC labeled by in vivo technique were administered intravenously and tomographic imaging of the intra-abdominal vascular blood pool was performed as follows. For each subject, 64 views were obtained over 360 deg of elliptic rotation at 30 seconds per view using a high resolution low energy parallel-hole collimator. Portal vein and portosystemic collaterals were clearly observed in coronal images. In 12 of 15 patients, portal vein was delineated. Portosystemic collaterals such as coronary vein, splenorenal shunt and umbilical vein were also shown in 12 patients. These images were consistent with images obtained by scintiphotosplenoportography or arterial portography. Therefore, it is considered that SPECT study for the intra-abdominal blood pool is clinically very useful for the diagnosis of abnormality of portal venous system in portal hypertension.

The fatal risk in hepatic artery embolization for hemostasis after pancreatic and hepatic surgery: importance of collateral arterial pathways.

Science.gov (United States)

Sato, Akihiro; Yamada, Takayuki; Takase, Kei; Matsuhashi, Toshio; Higano, Shuichi; Kaneda, Tomohiro; Egawa, Shinichi; Takeda, Kazunori; Ishibashi, Tadashi; Takahashi, Shoki

2011-03-01

To assess retrospectively the cause of hepatic failure related to hepatic arterial embolization (HAE) for hemostasis after pancreaticoduodenectomy or hepatic lobectomy. Between June 1993 and March 2006, Twenty HAEs in 17 patients (15 men, two women; mean age, 64 years) were performed. Angiographic findings, including portal vein stenosis, collateral arterial pathways after HAE, and the difference of embolic materials, were recorded. The morbidity (hepatic failure and abscess) and mortality were detailed according to collateral arterial pathways, portal vein stenosis, and embolic material used. Bleeding was controlled in all patients, although two patients required repeat embolization. Hepatic failure (n = 8) and abscess (n = 2) arose in nine of 20 HAEs. Death occurred after six of eight HAEs complicated by hepatic failure. The morbidity and mortality rates of HAE were 45% and 30%, respectively. Hepatic complication was eight times more likely to occur (P = .005) in cases with no hepatic collaterals involving hepatic, replaced, or accessory hepatic arteries. Death was observed only in the cases without hepatic collaterals (P = .011). The correlation between the embolization outcome and the presence of portal vein stenosis or the difference of embolic materials was not significant (P > .61). HAE can be used to successfully control bleeding secondary to hepatic arterial rupture. In the absence of hepatic collaterals, collateral circulation distal to the occlusion from nonhepatic sources may be inadequate and lead to hepatic failure after HAE. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

7 CFR 3575.90 - Disposition of acquired property.

Science.gov (United States)

2010-01-01

... property. (a) General. When the lender acquires title to the collateral and the final loss claim is not... 7 Agriculture 15 2010-01-01 2010-01-01 false Disposition of acquired property. 3575.90 Section... protect the collateral, and the lender must dispose of the collateral without delay. (b) Re-title...

Arachidonic acid metabolites and endothelial dysfunction of portal hypertension.

Science.gov (United States)

Sacerdoti, David; Pesce, Paola; Di Pascoli, Marco; Brocco, Silvia; Cecchetto, Lara; Bolognesi, Massimo

2015-07-01

Increased resistance to portal flow and increased portal inflow due to mesenteric vasodilatation represent the main factors causing portal hypertension in cirrhosis. Endothelial cell dysfunction, defined as an imbalance between the synthesis, release, and effect of endothelial mediators of vascular tone, inflammation, thrombosis, and angiogenesis, plays a major role in the increase of resistance in portal circulation, in the decrease in the mesenteric one, in the development of collateral circulation. Reduced response to vasodilators in liver sinusoids and increased response in the mesenteric arterioles, and, viceversa, increased response to vasoconstrictors in the portal-sinusoidal circulation and decreased response in the mesenteric arterioles are also relevant to the pathophysiology of portal hypertension. Arachidonic acid (AA) metabolites through the three pathways, cyclooxygenase (COX), lipoxygenase, and cytochrome P450 monooxygenase and epoxygenase, are involved in endothelial dysfunction of portal hypertension. Increased thromboxane-A2 production by liver sinusoidal endothelial cells (LSECs) via increased COX-1 activity/expression, increased leukotriens, increased epoxyeicosatrienoic acids (EETs) (dilators of the peripheral arterial circulation, but vasoconstrictors of the portal-sinusoidal circulation), represent a major component in the increased portal resistance, in the decreased portal response to vasodilators and in the hyper-response to vasoconstrictors. Increased prostacyclin (PGI2) via COX-1 and COX-2 overexpression, and increased EETs/heme-oxygenase-1/K channels/gap junctions (endothelial derived hyperpolarizing factor system) play a major role in mesenteric vasodilatation, hyporeactivity to vasoconstrictors, and hyper-response to vasodilators. EETs, mediators of liver regeneration after hepatectomy and of angiogenesis, may play a role in the development of regenerative nodules and collateral circulation, through stimulation of vascular endothelial

Idiopathic noncirrhotic portal hypertension: current perspectives.

Science.gov (United States)

Riggio, Oliviero; Gioia, Stefania; Pentassuglio, Ilaria; Nicoletti, Valeria; Valente, Michele; d'Amati, Giulia

2016-01-01

The term idiopathic noncirrhotic portal hypertension (INCPH) has been recently proposed to replace terms, such as hepatoportal sclerosis, idiopathic portal hypertension, incomplete septal cirrhosis, and nodular regenerative hyperplasia, used to describe patients with a hepatic presinusoidal cause of portal hypertension of unknown etiology, characterized by features of portal hypertension (esophageal varices, nonmalignant ascites, porto-venous collaterals), splenomegaly, patent portal, and hepatic veins and no clinical and histological signs of cirrhosis. Physicians should learn to look for this condition in a number of clinical settings, including cryptogenic cirrhosis, a disease known to be associated with INCPH, drug administration, and even chronic alterations in liver function tests. Once INCPH is clinically suspected, liver histology becomes mandatory for the correct diagnosis. However, pathologists should be familiar with the histological features of INCPH, especially in cases in which histology is not only requested to exclude liver cirrhosis.

Computed tomographic manifestations of abdominal and pelvic venous collaterals

International Nuclear Information System (INIS)

Pagani, J.J.; Thomas, J.L.; Bernardino, M.E.

1982-01-01

Obstruction of blood flow through the inferior vena cava and portal vein may produce venous collaterals. These include the paravertebral venous system and its communications with the ascending lumbar veins and azygous/hemiazygous system; gonadal, periureteric, and other retroperitoneal veins; abdominal wall veins; hemorrhoidal venous plexus; and the portal venous system. The anatomic location of these vessels is discussed. Computed tomography demonstrates them as round or tubular structures that are isodens when compared with other venous structures following contrast material administration. Techniques of examination and methods of differentiation of these vascular structures from other abnormalities, especially lymphadenopathy, are discussed

A novel canine model of portal vein stenosis plus thioacetamide administration-induced cirrhotic portal hypertension with hypersplenism.

Science.gov (United States)

Lin, Dexin; Wu, Xianbin; Ji, Xiaoke; Zhang, Qiyu; Lin, YuanWei; Chen, WeiJian; Jin, Wangxun; Deng, Liming; Chen, Yunzhi; Chen, Bicheng; Li, Jianmin

2012-01-01

Current large animal models that could closely resemble the typical features of cirrhotic portal hypertension in human have not been well established. Thus, we aimed to develop and describe a reliable and reproducible canine cirrhosis model of portal hypertension. A total of 30 mongrel dogs were randomly divided into four groups: 1 (control; n = 5), 2 (portal vein stenosis [PVS]; n = 5], 3 (thioacetamide [TAA]; n = 5), and 4 (PVS plus TAA; n = 15). After 4-months modeling period, liver and spleen CT perfusion, abdominal CT scans, portal hemodynamics, gastroscopy, hepatic function, blood routine, the bone marrow, liver, and spleen histology were studied. The animals in group 2 (PVS) developed extrahepatic portosystemic collateral circulation, particularly esophageal varices, without hepatic cirrhosis and portal hypertension. Animals from group 3 (TAA) presented mild cirrhosis and portal hypertension without significant symptoms of esophageal varices and hypersplenism. In contrast, animals from group 4 (PVS + TAA) showed well-developed micronodular and macronodular cirrhosis, associated with significant portal hypertension and hypersplenism. The combination of PVS and TAA represents a novel, reliable, and reproducible canine cirrhosis model of portal hypertension, which is associated with the typical characteristics of portal hypertension, including hypersplenism.

Outcome of the Pediatric Patients with Portal Cavernoma: The Retrospective Study for 10 Years Focusing on Recurrent Variceal Bleeding

Directory of Open Access Journals (Sweden)

Hongjie Guo

2016-01-01

Full Text Available Background. Portal cavernoma (PC is the most critical condition with risk or variceal hemorrhage in pediatric patients. We retrospectively investigated the patients with PC focusing on the predictors for recurrent variceal bleeding. Methods. Between July 2003 and June 2013, we retrospectively enrolled all consecutive patients admitted to our department with a diagnosis of PC without abdominal malignancy or liver cirrhosis. The primary endpoint of this observational study was recurrent variceal bleeding. Independent predictors of recurrent variceal bleeding were identified using the logistic regression model. Results. A total of 157 patients were enrolled in the study. During the follow-up period, 24 patients exhibited onset of recurrent variceal bleeding. Acute variceal bleeding was subjected to conservative symptomatic treatment and emergency endoscopic sclerotherapy. Surgical procedure selection was based on the severity of vascular dilation and collateral circulation. Multivariate logistic regression analysis demonstrated that the presence of ascites, collateral circulation, and portal venous pressure were independent prognostic factors of recurrent variceal bleeding for patients with portal cavernoma. Conclusions. The presence of ascites, collateral circulation, and portal venous pressure evaluation are important and could predict the postsurgical recurrent variceal bleeding in patients with portal cavernoma.

Case of idiopathic portalhypertension. Comparison of pre- and post-operative CT scan findings of collateral circulation

Energy Technology Data Exchange (ETDEWEB)

Serizawa, K; Yajima, Y; Onodera, H; Hirata, T; Sugawara, H [Tohoku Univ., Sendai (Japan). School of Medicine

1982-02-01

A 40-year-old man was referred to our clinic for esophageal varices. Histological examination of the liver biopsy samples revealed no sign of liver cirrhosis. Celiac angiography and ultrasound showed no obstruction of portal vein. A diagnosis of idiopathic portalhypertension was established. Splenomegaly and collateral circulation from spleen to left retroperitoneum were shown on CT scan and confirmed by surgical operation. CT scan following operation showed no collateral circulation.

Pattern of Venous Collateral Development after Splenic Vein Occlusion in an Extended Whipple Procedure (Whipple at the Splenic Artery) and Long-Term Results.

Science.gov (United States)

Rosado, Ismael Dominguez; Bhalla, Sanjeev; Sanchez, Luis A; Fields, Ryan C; Hawkins, William G; Strasberg, Steven M

2017-03-01

Extended Whipple procedures may require division of the splenic vein (SV). Controversy exists regarding the risk of sequelae of sinistral portal hypertension when the SV is ligated without reimplantation. The aim of this study was to identify postoperative venous collateral patterns and sequelae of SV ligation, as well as long-term results in an extended Whipple procedure. Patients who had an extended Whipple procedure (Whipple at the Splenic Artery or WATSA) were entered in an institutional database. Evaluation of the venous collaterals was performed at least 5 months postoperatively by imaging. Spleen size and platelet counts were measured before and after operation. Fifteen patients were entered from 2009 to 2014. SV was not reconstructed and the IMV-SV junction was always resected. Two collateral routes developed. An inferior route was present 14/15 patients. It connected the residual SV to the SMV via intermediate collateral veins in the omentum and along the colon. A superior route, present in 10/15 patients connected the residual SV to the portal vein via gastric, perigastric, and coronary veins. Gastrointestinal bleeding did not occur. Mean platelet count and spleen size were not affected significantly. Procedures were long, but few severe complications developed. In 12 patients with adenocarcinoma, the median survival has not been reached. Patients who have SV ligation in an extended Whipple are protected against sequelae of sinestral portal hypertension by inferior collateral routes. The omentum and marginal veins of the colon are key links in this pathway.

Gallbladder varices in extrahepatic portal venous obstruction: demonstration by intravenous

International Nuclear Information System (INIS)

Gulati, M.

2002-01-01

Full text: We performed a prospective study to determine frequency of presence of gallbladder varices (GBV) by intravenous CT portography (CTP) in patients with extrahepatic portal venous obstruction (EHPVO). 90 patients (age range: 2-55 years) with EHPVO (initially diagnosed on abdominal sonography) underwent CTP using a subsecond helical CT scanner. Axial overlapping sections of 2mm were obtained with collimation 3mm and table speed 4.5mm/sec (pitch 1.5). Presence and patterns of GBV were studied. CTP demonstrated GBV in 54 (60%) of 90 patients.GBV were said to be present when one or more of the following findings were seen: diffuse wall enhancement (26/90), pinpoint areas of enhancement in GB wall (33/90), obvious large collaterals in GB wall (8/90) and pericholecystic collaterals (49/90). Presence of GBV did not correlate with the site and extent of EHPVO. Contiguous intrahepatic collaterals extending from GB bed to intrahepatic portal vein branches were seen in 41 of 54 (76%) of patients with GBV, suggesting the role of GBV serving as bridging portoportal collaterals. Hepatic perfusion defects were seen in 5/54 patients with GBV and were not seen in remaining 36/90 patients of EHPVO. GB calculi were seen in only 4/54 cases with GBV (as determined on sonography) suggesting no increase in risk for cholelithiasis. GBV commonly develop as bridging collaterals in patients with EHPVO. CTP is very useful in detecting these varices and planning biliary surgery, given the frequency of iatrogenic surgical bleeding in these patients. Copyright (2002) Blackwell Science Pty Ltd

Transjugular intrahepatic portosystemic shunt in patients with active variceal bleeding due to portal hypertension and portal vein thrombosis

International Nuclear Information System (INIS)

Shin, Hyun Woong; Ryeom, Hun Kyu; Lee, Sang Kwon; Lee, Jong Min; Kim, Young Sun; Suh, Kyung Jin; Kim, Tae Hun; Kim, Yong Joo

1997-01-01

To evaluate the feasibility and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) in patients with active variceal bleeding due to liver cirrhosis and pre-existing portal vein thrombosis. Of a total of 123 patients who underwent TIPS, 14 patients with intractable variceal bleeding due to portal hypertension and portal vein thrombosis were included in this study. Noncavernomatous portal vein occlusion was seen in eight patients, and complete portal vein occlusion with cavernomatous trans-formation in six. For all patients, the methods used for TIPS placement were the same as those used in patients with patents portal veins. In seven of eight patients with noncavernomatous occlusion, right hepatic vein-right portal vein shunting was performed; in one with knoncavernomatous occlusion, a shunt was created between the right hepatic and left portal vein. In five of six patients with cavernomatous occlusion, the right hepatic and main portal vein were connected via a collateral vein. The procedures were technically successful in all except one patient. Immediate hemostatis was achieved after all technically successful procedures, and no significant complications were encountered. Minor complications were noted in six patients (three biliary tree punctures, one transperitoneal puncture, one splenic vein perforation, one hepatic subcapsular hematoma). TIPS is a technically feasible and hemodynamically effective procedure, even in patients with active variceal bleeding due to cirrhosis and complete portal vein occlusion

X-ray examination of the portal hypertension by means of indirect arterial portography

Energy Technology Data Exchange (ETDEWEB)

Vadon, G; Engloner, L; Kupcsulik, P; Konya, A [Semmelweis Orvostudomanyi Egyetem, Budapest (Hungary). Radiologiai Klinika; Semmelweis Orvostudomanyi Egyetem, Budapest (Hungary). 2. Sebeszeti Klinika)

1982-01-01

The blood flow in the portal system, its collaterals and the presence of any thrombus was examined by serial radiograms taken in the venous phase after catheterization of the a. coeliaca, linealis or mesenterica superior. In 127 out of 131 cases the examination was successful and gave valuable information. The method is recommended as a first investigation in cases of suspected portal hypertension.

Bilateral varicoceles as an indicator of underlying portal-hypertension

African Journals Online (AJOL)

A. Adam

2016-08-01

Aug 1, 2016 ... compression from the conglomerate of collateral veins (Fig. 2). Our index patient defaulted from follow up, further investigations and refused further treatment. Discussion. Patients with underlying portal hypertension and a porto-systemic shunt rarely present with a right-sided or bilateral varicocele. A.

Personalization Methods for Internet Portals

OpenAIRE

Barbara Dębska; Agnieszka Kubacka

2012-01-01

The article presents methods of acquiring and gathering data about users of internet portals, with particular emphasis on educational portals. Definitions, aims and tasks related to the process of personalization of e-learning portals are thoroughly discussed. So are knowledge acquisition techniques applied in personalization, especially artificial intelligence methods.

Evaluation of the portal venous system using MR angiography in patients with severe liver dysfunction

International Nuclear Information System (INIS)

Fukatsu, Hiroshi; Ando, Yoko; Yamakawa, Koji; Ishigaki, Takeo

1994-01-01

Fifteen patients of chronic liver dysfunction were examined with 2D TOF MR angiography to assess the portal venous system condition. All of the collateral pathways except esophageal varices were clearly demonstrated in all cases, portal vein thromboses were accurately diagnosed in two cases. Portal vein visualization index were determined as follows: good delineation of the main portal vein only; good delineation of the first tributaries of the intrahepatic portal vein; good delineation of the second or further tributaries. This index showed good correlation with the clinical stage proposed by Japan liver cancer study group. These results suggested that MR angiography has a potential for the evaluation of the portal system in patients with severe liver dysfunction. (author)

Computed tomographic characteristics of collateral venous pathways in dogs with caudal vena cava obstruction.

Science.gov (United States)

Specchi, Swan; d'Anjou, Marc-André; Carmel, Eric Norman; Bertolini, Giovanna

2014-01-01

Collateral venous pathways develop in dogs with obstruction or increased blood flow resistance at any level of the caudal vena cava in order to maintain venous drainage to the right atrium. The purpose of this retrospective study was to describe the sites, causes of obstruction, and configurations of venous collateral pathways for a group of dogs with caudal vena cava obstruction. Computed tomography databases from two veterinary hospitals were searched for dogs with a diagnosis of caudal vena cava obstruction and multidetector row computed tomographic angiographic (CTA) scans that included the entire caudal vena cava. Images for each included dog were retrieved and collateral venous pathways were characterized using image postprocessing and a classification system previously reported for humans. A total of nine dogs met inclusion criteria and four major collateral venous pathways were identified: deep (n = 2), portal (n = 2), intermediate (n = 7), and superficial (n = 5). More than one collateral venous pathway was present in 5 dogs. An alternative pathway consisting of renal subcapsular collateral veins, arising mainly from the caudal pole of both kidneys, was found in three dogs. In conclusion, findings indicated that collateral venous pathway patterns similar to those described in humans are also present in dogs with caudal vena cava obstruction. These collateral pathways need to be distinguished from other vascular anomalies in dogs. Postprocessing of multidetector-row CTA images allowed delineation of the course of these complicated venous pathways and may be a helpful adjunct for treatment planning in future cases. © 2014 American College of Veterinary Radiology.

Arteriomesentericography in patients with extrahepatic forms of portal hypertension

International Nuclear Information System (INIS)

Semenov, V.S.; Gotman, L.N.

1980-01-01

The reverse contrast examination of the system, carried out by means of superior arteriomesentericography, is the optimal method for diagnosing pathological changes in the portal channel of splenectomized patients with the syndrome of the extrahepatic form of portal hypertension. The selective catheterization of the superior mesenteric artery was made in 36 patients with the prerenal block of the portal system. In all cases the venous phase of portography was obtained, which served as a basis for selecting the amount of surgical intervention in these patients. Depending on the level of the block of the portal channel, the patients fell into 3 groups. The characteristic X-ray appearance of portal hypertension, manifested mainly by the presence of portoportal and portocaval collaterals, is described for each group. The thrombosis of the main vessels of the loose type of their structure excludes the possibility of portocaval anastomosis, while in the presence of the pronounced surgical trunk of the superior mesenteric vein vascular shunting may be recommended. Portal hypertension, in contrast to the normal state, requires prolonged contrast examination of the venous phase due to a slower portorenal blood flow

Perivesical varices and portal hypertension: imaging study

International Nuclear Information System (INIS)

Mallorquin Jimenez, F.; Medina Benitez, A.; Lopez Machado, E.; Pardo Moreno, M.D.; Garrido Moreno, C.; Pastor Rull, J.

1995-01-01

Nine patients with portal hypertension syndrome and Perivesical varices are studied retrospectively by means of imaging techniques including ultrasound, duplex Doppler, color Doppler, CT and angiography. All the patients presented portal thrombosis and thickening of the bladder wall. These collaterals either represent a shunting of hepato pedal flow or correspond to blood stasis associated with said syndrome. Ultrasound, whether involving duplex Doppler or color Doppler techniques, is highly useful to detect the presence of Perivesical varices which appear as tubular or rounded hypo echogenic areas in the bladder wall. Given the association of this entity with bladder wall thickening, it should be taken into account in any clinical situation involving said change, especially in patients with portal hypertension; moreover knowledge of its presence is of great importance when the possibility of creating shunts by means of interventional or surgical vascular procedures or other types of abdominal procedures are being considered because of the risk of bleeding. (Author)

Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

Directory of Open Access Journals (Sweden)

Jianlin Tang

2014-12-01

Conclusion: The lessons we learned are (1 Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2 Synthetic graft is an alternative for internal jugular vein graft. (3 Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4 It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.

Computer tomographic findings in portal hypertension due to cirrhosis of the liver. Pt. 1

International Nuclear Information System (INIS)

Koester, O.; Kunz, R.; Fischer, P.; Lackner, K.; Koischwitz, D.; Bonn Univ.

1983-01-01

The CT findings in 80 patients with confirmed portal hypertension due to intrahepatic block were analysed retrospectively. The findings included ascites, hypo-dense areas in the liver, nodular or irregular liver contour, the inability of define intrahepatic portal vessels with narrow window settings, the so-called ''kissing'' sign and evidence of hepato-fugal collaterals and thickning of the wall of the oesophagus. Electronic measurements of various organs (liver, spleen) and vessel diameters (portal vein, superior mesenteric vein) provide parameters which permit classification of patients into the cirrhotic group, as compared with a control group. The statistical significance of this classification was checked by the Kolmogoroff-Smirnoff test. (orig.)

Computer tomographic findings in portal hypertension due to cirrhosis of the liver. Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Koester, O; Kunz, R; Fischer, P; Lackner, K; Koischwitz, D

1983-06-01

The CT findings in 80 patients with confirmed portal hypertension due to intrahepatic block were analysed retrospectively. The findings included ascites, hypo-dense areas in the liver, nodular or irregular liver contour, the inability of define intrahepatic portal vessels with narrow window settings, the so-called ''kissing'' sign and evidence of hepato-fugal collaterals and thickening of the wall of the oesophagus. Electronic measurements of various organs (liver, spleen) and vessel diameters (portal vein, superior mesenteric vein) provide parameters which permit classification of patients into the cirrhotic group, as compared with a control group. The statistical significance of this classification was checked by the Kolmogoroff-Smirnoff test.

The Collateral Trap

OpenAIRE

Frédéric Boissay; Russell Cooper

2014-01-01

Active wholesale financial markets help reallocate deposits across heterogeneous banks. Because of incentive problems these flows are constrained and collateral is needed. The composition of collateral matters. The use of inside assets (loans) creates a “collateral pyramid” in that cash flows from one loan can be pledged to secure another. Through collateral pyramids the financial sector creates safe assets, but at the cost of exposing the economy to systemic panics. Outside collateral (treas...

The keys to successful TIPS in patients with portal vein thrombosis and cavernous transformation.

Science.gov (United States)

Lombardo, S; Espejo, J J; Pérez-Montilla, M E; Zurera, L J; González-Galilea, Á

Portal vein thrombosis is a common complication in patients with cirrhosis. Anticoagulation involves a high risk of bleeding secondary to portal hypertension, so placing transjugular intrahepatic portosystemic shunts (TIPS) has become an alternative treatment for portal vein thrombosis. Three strategies for TIPS placement have been reported: 1) portal recanalization and conventional implantation of the TIPS through the jugular vein; 2) portal recanalization through percutaneous transhepatic/transsplenic) access; and (3) insertion of the TIPS between the suprahepatic vein and a periportal collateral vessel without portal recanalization. We describe different materials that can be used as fluoroscopic targets for the TIPS needle and for portal recanalization. This article aims to show the success of TIPS implantation using different combinations of the techniques listed above, which is a good treatment alternative in these patients whose clinical condition makes them difficult to manage, and to show that portal vein thrombosis/cavernous transformation should not be considered a contraindication for TIPS. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Loan collaterals and collateral substitutes in rural finance: a review ...

African Journals Online (AJOL)

Loan collaterals and collateral substitutes in rural finance: a review. ... have difficulties in obtaining loans from banks and other financial institutions because ... The limited availability of conventional collaterals in rural financial markets has led ...

Portal venous perfusion steal causing graft dysfunction after orthotopic liver transplantation: serial imaging findings in a successfully treated patient

Energy Technology Data Exchange (ETDEWEB)

Lee, Min Su; Chung, Yong Eun; Choi, Jin Young; Park, Mi Suk; Lim, Joon Seok; Kim, Myeong Jin; Kim, Hon Soul [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Sang Kyun [Dept. of Pathology, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2016-01-15

A 53-year-old male with hepatocellular carcinoma underwent orthotopic liver transplantation. Preoperative computed tomography revealed main portal vein luminal narrowing by flat thrombi and the development of cavernous transformation. On post-transplantation day 1, thrombotic portal venous occlusion occurred, and emergency thrombectomy was performed. Subsequent Doppler ultrasonography and contrast-enhanced ultrasonography confirmed the restoration of normal portal venous flow. The next day, however, decreased portal venous velocity was observed via Doppler ultrasonography, and serum liver enzymes and bilirubin levels remained persistently elevated. Direct portography identified massive perfusion steal through prominent splenorenal collateral veins. Stent insertion and balloon angioplasty of the portal vein were performed, and subsequent Doppler ultrasonography demonstrated normalized portal flow parameters. Afterwards, the serum liver enzymes and bilirubin levels rapidly normalized.

The relationship of CT signs of portal hypertension and histopathologic stage of chronic hepatic fibrosis and cirrhosis

International Nuclear Information System (INIS)

Ding Ke; Huang Zhongkui; Long Liling; Lin Shengcai; Li Chunlan; Jiang Jianning

2008-01-01

Objective: To investigate the relationship between CT signs of portal hypertension and histopathologic stage of chronic hepatic fibrosis and cirrhosis. Methods: Tri-stage enhance volume CT scan of upper abdomen was performed in 84 participants, including 48 patients with hepatic fibrosis confirmed by liver pathologic biopsy which divided into S1 (12/48), S2(14/48), S3 (9/48) and S4 (13/48) , 16 patients with typical cirrhosis, and 20 healthy subjects as a control group. Measured the caliber of left and right branch of portal vein, MPV, SV and SMV at MIP images respectively, observed the collateral circulation, ascites and the size of spleen and then studied comparatively these measured parameters of different histopathologic stage. One-Way ANOVA was performed in the comparison of the vascular diameter of portal system and the size of spleen (SNK was used in the comparison between the groups). χ 2 test of R x C table was performed in the comparison of ascites and collateral circulation among groups, and the vessel of portal system which has the greatest impact on the pathological staging of hepatic fibrosis was investigated with Logistic regression analysis. Results: The caliber of left branch of portal vein, right branch of portal vein, MPV, SV and SMV were (0.98±0.11), (1.00±0.12), (1.33±0.11), (0.75±0.10), (1.07±0.12) cm respectively, the size of spleen was (128.55±30.56) cm 3 , and collateral circulation and ascites were not found in control group. SV enlarged gradually in test groups and showed S1 (0.86±0.12) cm, S2(0.96±0.11) cm, S3(1.07±0.08) cm, S4(1.09±0.10) cm, typical cirrhosis (1.18±0.19) cm respectively. The difference between each group of S1 to typical cirrhosis and control group was significant, and the same result was seen among S3 to S4, cirrhosis and S1 to S2. Logistic regression analysis showed that the standardized regression coefficient of SV was maximum (2.719) and had statistical significance (P <0.01). The incidence of collateral

Computed tomographic and ultrasonographic diagnosis of portal vein tumor thrombus in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Mori, H; Futagawa, S; Hayashi, K; Amagasaki, Y; Ochi, M [Nagasaki Univ. (Japan). School of Medicine

1982-04-01

Nine cases of hepatocellular carcinoma which have invaded the intra- and extrahepatic portal vein were evaluated by computed tomography (CT) and ultrasonography (US). The outstanding CT and sonographic features of the portal vein tumor thrombus were described. In CT, contrast opacification of normal portal vein and its major tributaries were not observed, and they were replaced by a soft tissue density mass representing the tumor thrombus. The thrombus measured 35 - 45 Hounsfield units (HU) in precontrast scans and 60 - 80 HU in postcontrast scans. The portal vein tumor thrombus showed a branched pattern of low density in porta hepatis and intrahepatic region due to differences in attenuation coefficients of the thrombus and adjacent noncancerous hepatic parenchyma on postcontrast scans. In ultrasound study, tumor thrombus was recognized as an echogenic solid mass in the porta hepatis obliterating the normal portal venous structures, or as an intraluminal solid mass in the dilated portal vein and its branches. Numerous collateral venous channels surrounding the thrombosed portal vein were also demonstrated on both CT and US. Particular emphasis was placed on the clinical implications of these non-invasive detection of the portal vein tumor thrombosis in patients with hepatocellular carcinoma.

Effects of exercise training on coronary collateralization and control of collateral resistance

Science.gov (United States)

Parker, Janet L.

2011-01-01

Coronary collateral vessels serve as a natural protective mechanism to provide coronary flow to ischemic myocardium secondary to critical coronary artery stenosis. The innate collateral circulation of the normal human heart is typically minimal and considerable variability occurs in extent of collateralization in coronary artery disease patients. A well-developed collateral circulation has been documented to exert protective effects upon myocardial perfusion, contractile function, infarct size, and electrocardiographic abnormalities. Thus therapeutic augmentation of collateral vessel development and/or functional adaptations in collateral and collateral-dependent arteries to reduce resistance into the ischemic myocardium represent a desirable goal in the management of coronary artery disease. Tremendous evidence has provided documentation for the therapeutic benefits of exercise training programs in patients with coronary artery disease (and collateralization); mechanisms that underlie these benefits are numerous and multifaceted, and currently under investigation in multiple laboratories worldwide. The role of enhanced collateralization as a major beneficial contributor has not been fully resolved. This topical review highlights literature that examines the effects of exercise training on collateralization in the diseased heart, as well as effects of exercise training on vascular endothelial and smooth muscle control of regional coronary tone in the collateralized heart. Future directions for research in this area involve further delineation of cellular/molecular mechanisms involved in effects of exercise training on collateralized myocardium, as well as development of novel therapies based on emerging concepts regarding exercise training and coronary artery disease. PMID:21565987

Trans-anastomotic porto-portal varices in patients with gastrointestinal haemorrhage

International Nuclear Information System (INIS)

Mitchell, A.W.M.; Jackson, J.E.

2000-01-01

AIM: Porto-portal varices are commonly seen in patients with segmental extra-hepatic portal hypertension and develop to provide a collateral circulation around an area of portal venous obstruction. It is not well recognized that such communications may also develop across surgical anastomoses and be the source of gastrointestinal haemorrhage. The possible mode of development of such communications has not been previously discussed. MATERIALS AND METHODS: Over a 3-year period between 1995 and 1998, porto-portal varices were demonstrated across surgical anastomoses in four patients who were referred for the investigation of acute (two), acute-on-chronic (one) and chronic gastrointestinal bleeding (one). Their medical notes and the findings at angiography were reviewed. RESULTS: Three patients had segmental portal hypertension due to extra-hepatic portal vein (one) or superior mesenteric vein (two) stenosis/occlusion. One patient had mild portal hypertension due to hepatic fibrosis secondary to congenital biliary atresia. At angiography all patients were shown to have varices crossing previous surgical anastomoses. These varices were presumed to be the cause of bleeding in three of the four patients; the site of bleeding in the fourth individual was not determined. CONCLUSIONS: Trans-anastomotic porto-portal varices are rare. They develop in the presence of extra-hepatic portal hypertension and presumably arise within peri-anastomotic inflammatory tissue. Such varices may be difficult to manage and their prognosis is poor when bleeding occurs. Mitchell, A.W.M., Jackson, J.E. (2000)

Superior vena cava syndrome associated with right-to left shunt through systemic-to-pulmonary venous collaterals

International Nuclear Information System (INIS)

Juan, Yu Hsiang; Saboo, Sachin S.; Anand, Vishal; Chatzizisis, Yiannis S.; Steigner, Michael L.; Lin, Yu Ching

2014-01-01

Superior vena cava (SVC) obstruction is associated with the gradual development of venous collaterals. We present a rare form of systemic-to-pulmonary subpleural collateral pathway that developed in the bridging subpleural pulmonary veins in a 54-year-old woman with complete SVC obstruction. This uncommon collateral pathway represents a rare form of acquired right-to-left shunt due to previous pleural adhesions with an increased risk of stroke due to right-to-left venous shunting, which requires lifelong anticoagulation.

The Changing Collateral Space

OpenAIRE

Manmohan Singh

2013-01-01

This paper highlights the changing collateral landscape and how it may shape the global demand/supply for collateral. We first identify the key collateral pools (relative to the “old” collateral space) and associated collateral velocities. Post-Lehman and continuing into the European crisis, some aspects of unconventional monetary policies pursued by central banks are significantly altering the collateral space. Moreover, regulatory demands stemming from Basel III, Dodd Frank, EMIR etc., new ...

Portal circulation following the Warren procedure. Long-term follow-up by computed tomography

Energy Technology Data Exchange (ETDEWEB)

Gostner, P; Fugazzola, C; Martin, F; Marzoli, G P

1986-06-01

Computed tomography with contrast injection was carried out in 18 patients who had undergone a Warren procedure for portal hypertension due to cirrhosis of the liver more than five years previously. The results show that it is not possible to drain only a part of the venous portal territory. The portal circulation does not consist of two portions, with different pressure relationships. Pressure difference across the splenorenal anastomosis is greater than that into the mediastinal veins. Postoperative development of a hepatofugal circulation continues for a long period and is not confined to the early phase only. This phenomenon is, however, not uniform. In particular, there are variations in the extent of the collateral circulation and in the maintenance of liver blood flow.

Determinants of leptomeningeal collateral flow in stroke patients with a middle cerebral artery occlusion

International Nuclear Information System (INIS)

Seeters, Tom van; Velthuis, Birgitta K.; Biessels, Geert Jan; Kappelle, L.J.; Graaf, Yolanda van der

2016-01-01

Poor leptomeningeal collateral flow is related to worse clinical outcome in acute ischemic stroke, but the factors that determine leptomeningeal collateral patency are largely unknown. We explored the determinants of leptomeningeal collateral flow and assessed their effect on the relation between leptomeningeal collateral flow and clinical outcome. We included 484 patients from the Dutch acute stroke study (DUST) with a middle cerebral artery (MCA) occlusion. The determinants of poor leptomeningeal collateral flow (≤50 % collateral filling) were identified with logistic regression. We calculated the relative risk (RR) of poor leptomeningeal collateral flow in relation to poor clinical outcome (90-day modified Rankin Scale 3-6) using Poisson regression and assessed whether the determinants of leptomeningeal collateral flow affected this relation. Leptomeningeal collateral flow was poor in 142 patients (29 %). In multivariable analyses, higher admission glucose level (odds ratio (OR) 1.1 per mmol/L increase (95 % CI 1.0-1.2)), a proximal MCA occlusion (OR 1.9 (95 % CI 1.3-3.0)), and an incomplete posterior circle of Willis (OR 1.7 (95 % CI 1.1-2.6)) were independently related to poor leptomeningeal collateral flow. Poor leptomeningeal collateral flow was related to poor clinical outcome (unadjusted RR 1.7 (95 % CI 1.4-2.0)), and this relation was not affected by the determinants of leptomeningeal collateral flow. Our study shows that admission glucose level, a proximal MCA occlusion, and an incomplete ipsilateral posterior circle of Willis are determinants of leptomeningeal collateral flow that represent a combination of congenital, acquired, and acute factors. After adjustment for these determinants, leptomeningeal collateral flow remains related to clinical outcome. (orig.)

Determinants of leptomeningeal collateral flow in stroke patients with a middle cerebral artery occlusion

Energy Technology Data Exchange (ETDEWEB)

Seeters, Tom van; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Biessels, Geert Jan; Kappelle, L.J. [University Medical Center Utrecht, Department of Neurology, Brain Center Rudolf Magnus, Utrecht (Netherlands); Graaf, Yolanda van der [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Collaboration: on behalf of the Dutch acute stroke study (DUST) investigators

2016-10-15

Poor leptomeningeal collateral flow is related to worse clinical outcome in acute ischemic stroke, but the factors that determine leptomeningeal collateral patency are largely unknown. We explored the determinants of leptomeningeal collateral flow and assessed their effect on the relation between leptomeningeal collateral flow and clinical outcome. We included 484 patients from the Dutch acute stroke study (DUST) with a middle cerebral artery (MCA) occlusion. The determinants of poor leptomeningeal collateral flow (≤50 % collateral filling) were identified with logistic regression. We calculated the relative risk (RR) of poor leptomeningeal collateral flow in relation to poor clinical outcome (90-day modified Rankin Scale 3-6) using Poisson regression and assessed whether the determinants of leptomeningeal collateral flow affected this relation. Leptomeningeal collateral flow was poor in 142 patients (29 %). In multivariable analyses, higher admission glucose level (odds ratio (OR) 1.1 per mmol/L increase (95 % CI 1.0-1.2)), a proximal MCA occlusion (OR 1.9 (95 % CI 1.3-3.0)), and an incomplete posterior circle of Willis (OR 1.7 (95 % CI 1.1-2.6)) were independently related to poor leptomeningeal collateral flow. Poor leptomeningeal collateral flow was related to poor clinical outcome (unadjusted RR 1.7 (95 % CI 1.4-2.0)), and this relation was not affected by the determinants of leptomeningeal collateral flow. Our study shows that admission glucose level, a proximal MCA occlusion, and an incomplete ipsilateral posterior circle of Willis are determinants of leptomeningeal collateral flow that represent a combination of congenital, acquired, and acute factors. After adjustment for these determinants, leptomeningeal collateral flow remains related to clinical outcome. (orig.)

Stroke etiology and collaterals: atheroembolic strokes have greater collateral recruitment than cardioembolic strokes.

Science.gov (United States)

Rebello, L C; Bouslama, M; Haussen, D C; Grossberg, J A; Dehkharghani, S; Anderson, A; Belagaje, S R; Bianchi, N A; Grigoryan, M; Frankel, M R; Nogueira, R G

2017-06-01

Chronic hypoperfusion from athero-stenotic lesions is thought to lead to better collateral recruitment compared to cardioembolic strokes. It was sought to compare collateral flow in stroke patients with atrial fibrillation (AF) versus stroke patients with cervical atherosclerotic steno-occlusive disease (CASOD). This was a retrospective review of a prospectively collected endovascular database. Patients with (i) anterior circulation large vessel occlusion stroke, (ii) pre-treatment computed tomography angiography (CTA) and (iii) intracranial embolism from AF or CASOD were included. CTA collateral patterns were evaluated and categorized into two groups: absent/poor collaterals (CTA collateral score 0-1) versus moderate/good collaterals (CTA collateral score 2-4). CT perfusion was also utilized for baseline core volume and evaluation of infarct growth. A total of 122 patients fitted the inclusion criteria, of whom 88 (72%) had AF and 34 (27%) CASOD. Patients with AF were older (P Collateral scores were lower in the AF group (P = 0.01) with patients having poor collaterals in 28% of cases versus 9% in the CASOD group (P = 0.03). Mortality rates (20% vs. 0%; P = 0.02) were higher in the AF patients whilst rates of any parenchymal hemorrhage (6% vs. 26%; P collaterals (odds ratio 4.70; 95% confidence interval 1.17-18.79; P = 0.03). Atheroembolic strokes seem to be associated with better collateral flow compared to cardioembolic strokes. This may in part explain the worse outcomes of AF-related stroke. © 2017 EAN.

Gallblader varices in children with portal cavernoma: duplex-Doppler and color Doppler ultrasound studies

International Nuclear Information System (INIS)

Muro, D.; Sanguesa, C.; Lopez, A.

1998-01-01

To determine the prevalence of varices in the gallbladder wall, observed by duplex-Doppler and color Doppler ultrasound, in children with cavernoma of the portal vein. Nineteen patients with portal hypertension were studied prospectively by duplex-Doppler and color Doppler ultrasound: 12 of the patients had developed a cavernoma of the portal vein. The presence of peri vesicular varices was assessed in the group of patients with portal cavernoma. Duplex-Doppler and color Doppler ultrasound disclosed the presence of varices in gallbladder wall in nine of the 12 patients (75%). The varices appeared as anechoic and serpiginous areas, and Doppler ultrasound revealed slowed venous flow. However, the three patients in whom gallbldder varices were not detected presented collateral gastric ciculation and spontaneous splenorenal shunt. Gallbladder varices are common in children with portal vein cavernoma; they present hepatopetal flow. Their developments is not related to the size of the portal cavernoma, the presence of spontaneous portosystemic shunts, or endoscopic obliteration of gastric and esophageal varices. The detection of gallbladder varices in patients with portal hypertension who are to undergo biliary surgery is highly important for the surgeon, helping to avoid perioperative complications. (Author) 15 refs

Contemporary concepts of the medical therapy of portal hypertension under liver cirrhosis.

Science.gov (United States)

Garbuzenko, Dmitry Victorovich

2015-05-28

Severe complications of liver cirrhosis are mostly related to portal hypertension. At the base of the pathogenesis of portal hypertension is the increase in hepatic vascular resistance to portal blood flow with subsequent development of hyperdynamic circulation, which, despite of the formation of collateral circulation, promotes progression of portal hypertension. An important role in its pathogenesis is played by the rearrangement of vascular bed and angiogenesis. As a result, strategic directions of the therapy of portal hypertension under liver cirrhosis include selectively decreasing hepatic vascular resistance with preserving or increasing portal blood flow, and correcting hyperdynamic circulation and pathological angiogenesis, while striving to reduce the hepatic venous pressure gradient to less than 12 mmHg or 20% of the baseline. Over the last years, substantial progress in understanding the pathophysiological mechanisms of hemodynamic disorders under liver cirrhosis has resulted in the development of new drugs for their correction. Although the majority of them have so far been investigated only in animal experiments, as well as at the molecular and cellular level, it might be expected that the introduction of the new methods in clinical practice will increase the efficacy of the conservative approach to the prophylaxis and treatment of portal hypertension complications. The purpose of the review is to describe the known methods of portal hypertension pharmacotherapy and discuss the drugs that may affect the basic pathogenetic mechanisms of its development.

Laparoscopic splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension

Science.gov (United States)

Zhan, Xiao-Li; Ji, Yun; Wang, Yue-Dong

2014-01-01

Since the first laparoscopic splenectomy (LS) was reported in 1991, LS has become the gold standard for the removal of normal to moderately enlarged spleens in benign conditions. Compared with open splenectomy, fewer postsurgical complications and better postoperative recovery have been observed, but LS is contraindicated for hypersplenism secondary to liver cirrhosis in many institutions owing to technical difficulties associated with splenomegaly, well-developed collateral circulation, and increased risk of bleeding. With the improvements of laparoscopic technique, the concept is changing. This article aims to give an overview of the latest development in laparoscopic splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension. Despite a lack of randomized controlled trial, the publications obtained have shown that with meticulous surgical techniques and advanced instruments, LS is a technically feasible, safe, and effective procedure for hypersplenism secondary to cirrhosis and portal hypertension and contributes to decreased blood loss, shorter hospital stay, and less impairment of liver function. It is recommended that the dilated short gastric vessels and other enlarged collateral circulation surrounding the spleen be divided with the LigaSure vessel sealing equipment, and the splenic artery and vein be transected en bloc with the application of the endovascular stapler. To support the clinical evidence, further randomized controlled trials about this topic are necessary. PMID:24914339

Splenic radionuclide angiography in the portal hypertension assessment

International Nuclear Information System (INIS)

Artiko, V.; Kostic, K.; Perisic-Savic, M.; Janosevic, S.; Obradovic, V.

2004-01-01

The aim of this study is the presentation of the hepatic and splenic radionuclide angiograms (SRA) in various portal blood flow disturbances, as well as an analysis of the splenic arterio-venous ratio (SAVR) results, obtained as a slope ratio between inflow, arterial and the outflow, venous phases on the splenic TA curve. Splenic radionuclide angiography was performed after bolus injection of 740 MBq of 99m-Tc-pertechnetate, using ROTA scintillation camera (Siemens) and MicroDelta computer'. Four types of the SRA were established: a) very acute descendent slope (DS) in the controls; b) less acute DS in the patients with LC; c) horisontal venous phase caused by impaired outflow to the portal vein in LC with expressed portal hypertension, collateral circulation and LCEV; d) ascending outflow phase, characterizing the splenic and/or portal venous thrombosis. SAVR values were increased in liver cirrhosis (LC) with esophageal vahces (LCEV, n=10) (6.1 +/- 3.4) in comparison to the controls (n=10)(3.7 +/- 1.3)(U=25, p 0.05). However, in another two patients with LC and in 8 with LCEV it was not possible to access SAVR because of the appearance of the horisontal or rising venous phase on the splenic TA curve, instead of descendent. SRA and increased SAVR values reflect various blood flow alterations in the portal system and give additional data to the more accurate interpretation of the results obtained by hepatic radionuclide angiography. (authors)

Evaluation of usefulness of portal image using Electronic Portal Imaging Device (EPID) in the patients who received pelvic radiation therapy

International Nuclear Information System (INIS)

Kim, Woo Chul; Kim, Heon Jong; Park, Seong Young; Cho, Young Kap; Loh, John J. K.; Park, Won; Suh, Chang Ok; Kim, Gwi Eon

1998-01-01

To evaluate the usefulness of electronic portal imaging device through objective compare of the images acquired using an EPID and a conventional port film. From Apr. to Oct. 1997, a total of 150 sets of images from 20 patients who received radiation therapy in the pelvis area were evaluated in the Inha University Hospital and Severance Hospital. A dual image recording technique was devised to obtain both electronic portal images and port film images simultaneously with one treatment course. We did not perform double exposure. Five to ten images were acquired from each patient. All images were acquired from posteroanterior (PA) view except images from two patients. A dose rate of 100-300 MU/min and a 10-MV X-ray beam were used and 2-10 MUs were required to produce a verification image during treatment. Kodak diagnostic film with metal/film imaging cassette which was located on the top of the EPID detector was used for the port film. The source to detector distance was 140 cm. Eight anatomical landmarks (pelvic brim, sacrum, acetabulum, iliopectineal line, symphysis, ischium, obturator foramen, sacroiliac joint) were assessed. Four radiation oncologist joined to evaluate each image. The individual landmarks in the port film or in the EPID were rated-very clear (1), clear (2), visible (3), notclear (4), not visible (5). Using an video camera based EPID system, there was no difference of image quality between no enhanced EPID images and port film images. However, when we provided some change with window level for the portal image, the visibility of the sacrum and obturator foramen was improved in the portal images than in the port film images. All anatomical landmarks were more visible in the portal images than in the port film when we applied the CLAHE mode enhancement. The images acquired using an matrix ion chamber type EPID were also improved image quality after window level adjustment. The quality of image acquired using an electronic portal imaging device was

Axonal collateral-collateral transport of tract tracers in brain neurons: false anterograde labelling and useful tool.

Science.gov (United States)

Chen, S; Aston-Jones, G

1998-02-01

It is well established that some neuroanatomical tracers may be taken up by local axonal terminals and transported to distant axonal collaterals (e.g., transganglionic transport in dorsal root ganglion cells). However, such collateral-collateral transport of tracers has not been systematically examined in the central nervous system. We addressed this issue with four neuronal tracers--biocytin, biotinylated dextran amine, cholera toxin B subunit, and Phaseolus vulgaris-leucoagglutinin--in the cerebellar cortex. Labelling of distant axonal collaterals in the cerebellar cortex (indication of collateral-collateral transport) was seen after focal iontophoretic microinjections of each of the four tracers. However, collateral-collateral transport properties differed among these tracers. Injection of biocytin or Phaseolus vulgaris-leucoagglutinin in the cerebellar cortex yielded distant collateral labelling only in parallel fibres. In contrast, injection of biotinylated dextran amine or cholera toxin B subunit produced distant collateral labelling of climbing fibres and mossy fibres, as well as parallel fibres. The present study is the first systematic examination of collateral-collateral transport following injection of anterograde tracers in brain. Such collateral-collateral transport may produce false-positive conclusions regarding neural connections when using these tracers for anterograde transport. However, this property may also be used as a tool to determine areas that are innervated by common distant afferents. In addition, these results may indicate a novel mode of chemical communication in the nervous system.

Discounting with Imperfect Collateral

OpenAIRE

Lou, Wujiang

2017-01-01

Cash collateral is perfect in that it provides simultaneous counterparty credit risk protection and derivatives funding. Securities are imperfect collateral, because of collateral segregation or differences in CSA haircuts and repo haircuts. Moreover, the collateral rate term structure is not observable in the repo market, for derivatives netting sets are perpetual while repo tenors are typically in months. This article synthesizes these effects into a derivative financing rate that replaces ...

Using collateral to secure loans

OpenAIRE

Yaron Leitner

2006-01-01

In “Using Collateral to Secure Loans,” Yaron Leitner asks: Why is collateral used to secure some loans, but not others? And why does collateral potentially involve more risk? He considers these questions, looking at some of the explanations for using collateral, focusing on its benefits and drawbacks.

7 CFR 1980.331 - Collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Collateral. 1980.331 Section 1980.331 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.331 Collateral. (a) General. The entire loan must... borrower. (c) All collateral must secure the entire loan. The Lender will not take separate collateral...

Portal hypertension in schistosomiasis: pathophysiology and treatment

Directory of Open Access Journals (Sweden)

Luiz Caetano da Silva

1992-01-01

Full Text Available In heavily infected young patients, there is a "non-congestive" phase of the disease with splenomegaly which can improve after chemoterapy. A strong correlation between hepatosplenic form and worm burden in young patients has been repeatedly shown. The pattern of vascular intrhepatic lesions seems to depend on two mechanisms: (a egg embolization, with a partial blocking of the portal vasculature; (b the appearance of small portal collaterals along the intrahepatic portal sistem. The role played by hepatitis B virus (HBV and C virus infections in the pathogenesis of liver lesions is variably considered. Selective arteriography shows a reduced diameter of hepatic artery with thin and arched branches outlining vascular gaps. A rich arterial network , as described in autopsy cases, is usually not seen in vivo, except after splenectomy or shunt surgery. An augmented hepatic arterial flow was demonstrated in infected animals. These facts suggest that the poor intrahepatic arterial vascularization demonstrated by selective arteriography in humans is due to a "functional deviation"of arterial blood to the splenic territory. The best results obtained in treatment of portal hypertension were: esophagogastric desvascularization and splenectomy (EGDS, although risk of rebleeding persists; classical (proximal splenorenal shunt (SRS should be abandoned; distal splenorenal shunt may complicate with hepatic encephalopaty, although later and in a lower percentage than in SRS. Propranolol is currently under investigation. In our Department, schistosomotic patients with esophageal varices bleeding are treated by EGDS and, if rebleeding occurs, by sclerosis of the varices.

Retrograde approach for the recanalization of coronary chronic total occlusion: collateral selection and collateral related complication.

Science.gov (United States)

Ma, Jian-Ying; Qian, Ju-Ying; Ge, Lei; Fan, Bing; Wang, Qi-Bing; Yan, Yan; Zhang, Feng; Yao, Kang; Huang, Dong; Ge, Jun-Bo

2013-03-01

The retrograde approach through collaterals has been applied in the treatment of chronic total occlusion (CTO) lesions during percutaneous recanalization of coronary arteries. This study was to investigate the success rate of recanalization and collateral related complications in patients when using the retrograde approach. Eighty-four cases subjected to retrograde approach identified from July 2005 to July 2012 were included in this study. Patient characteristics, procedural outcomes and in-hospital clinical events were evaluated. Mean age of the patient was (59.6 ± 11.2) years old and 91.7% were men. The target CTO lesions were distributed among the left anterior descending artery in 45 cases (53.5%), left circumflex artery in one case (1.2%), right coronary artery in 34 cases (40.5%), and left main in four cases (4.8%). The overall success rate of recanalization was 79.8%. The septal collateral was three times more frequently used for retrograde access than the epicardial collateral, 68/84 (81%) vs. 16/84 (19%). Successful wire passage through the collateral channel was achieved in 58 (72.6%) patients. The success rate of recanalization was 93.1% (54/58) in patients with and 50% (13/26) in patients without successful retrograde wire passage of the collateral channel (P collaterals was achieved in 49 of 68 septal collaterals (72.1%) and in 9 of 16 epicardial collaterals (56.3%) (P = NS). There was no significant difference between the septal collateral group and the epicardial group in the success rate of recanalization after retrograde wire crossing the collaterals (91.8% vs. 100%, P > 0.05). CART or reverse CART technique was used in 15 patients, and 14 patients (93.3%) were recanalized successfully. Collateral related perforation occurred in three (18.8%) cases with the epicardial collateral as the first choice (compared with the septal collateral group (0), P collaterals. The retrograde approach is an effective technique to recanalize CTO lesions, the septal

Evaluation of portal hypertension in cirrhotic patients using color duplex-doppler ultrasound. Preliminary study; Evaluacion de la hipertension portal del cirrotico mediante ultrasonografia duplex-Doppler color. Estudio prliminar

Energy Technology Data Exchange (ETDEWEB)

Varas, M J; Torres, G; Sanllely, H [Unidad de Ecografias, Consorcio del Hospital de la Cruz Roja, L` Hospitalet de Llobregat, Barcelona (Spain)

1996-09-01

The objective was to compare data obtained by color duplex-Doppler ultrasound (mean velocity, flow and portal vein congestion index) in patients with chronic diffuse liver disease with and without portal hypertension (PH) (demonstrated endoscopically) with that of a healthy control group. Over a two-year period, 50 studies were performed in 10 healthy subjects (control group) with a mean age of 36 years and in 40 chronic liver disease patients (study group with a mean age of 58 years), most of whom presented alcoholic liver cirrhosis and belonged to Child-Pugh class B. They were subdivided according to endoscopic study into patients without (group 1) and with (group 2) portal hypertension. There were statistically significant differences in the diameters of splenic vein, spleen, portal vein and in the portal Vm, which decreased as the Child-Pugh score rose. When the patients without (group 1) and with (group 2) endoscopic evidence of PH (esophageal varices)were analyzed and compared, the two groups presented no statistically significant differences with respect to portal Vm, blood flow out of the liver, presence of collateral vessels, or the portal vein congestion index; the latter was significantly different in both the study group as a whole and in the patients with PH when compared with the control group. Given that this report is based on a pilot study which requires a larger sample number, we are unable to arrive at definitive conclusions. (Author) 18 refs.

The usefulness and the limitation of MR angiography for the evaluation of colateral veins in portal hypertension

International Nuclear Information System (INIS)

Komazaki, Toshio

1994-01-01

The usefulness and the limitation of magnetic resonance angiography (MRA) for the assessment of the portal vein and its branches, i.e., the collateral veins of portal hypertensive patients, were studied. In a total of 22 patients with portal hypertension, both MRA and percutaneous transhepatic portography (PTP) were done at the same time. MRA and PTP images were read at random by three observers. The discriminative scores, decided from the grades of clearness of images, were calculated for six portal venous vessels. The discrimination of the portal vein, splenic vein, paraumbilical vein and gastrorenal shunt was easy on condition that they were clearly visualized by PTP. Thus the accuracy of MRA, which was calculated by comparing it with PTP, the gold standard, was high and above 95%. Regarding the left gastric vein and short gastric vein, the accuracy of MRA were lower than the former four vessels but were still above 80%. MRA, the noninvasive method, seems useful for the first choice to see the total image of portal venous system. (author)

Protection of estrogen in portal hypertension gastropathy: an experimental model

Directory of Open Access Journals (Sweden)

Maria Isabel Morgan-Martins

2011-09-01

Full Text Available CONTEXT: Portal hypertension is a complication secondary to cirrhosis that is characterized by increased blood flow and/or vascular resistance in the portal system, causing the appearance of a hyperdynamic collateral circulation. Partial portal vein ligation is an experimental model used in rats to study the pathophysiological mechanisms involved in pre-hepatic portal hypertension. Estrogen E2 is an antioxidant molecule with various physiological actions. OBJECTIVES: To evaluate the antioxidant activity of endogenous estrogen in an experimental model of partial portal vein ligation by comparing intact with castrated rats. METHODS: Twenty Wistar rats, weighing on average 250 g were used and divided into four groups: sham-operated (SO; intact (I with partial portal vein ligation (I + PPVL, castrated (C and castrated with partial ligation of the vein (C + PPVL. Day 1: castration or sham-operation; day 7, PPVL surgery; on day 15 post-PPVL, portal pressure in the mesenteric vein of rats was measured on polygraph Letica. Lipid peroxidation in the stomach was assessed using the technique of thiobarbituric acid reactive substances and activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase. Statistical analysis was done with ANOVA - Student-Newman-Keuls (mean ± SE, and P<0.05 was considered as significant. RESULTS: Portal pressure was significantly increased in C + PPVL as compared to the other groups. There was no significant difference in the group of intact rats. TBARS showed significant damage in C and C + PPVL in relation to others. Antioxidant enzymes were significantly increased in the castrated rats with subsequent PPVL as compared to the other groups. CONCLUSION: We suggest that estrogen E2 plays a protective role in intact compared with castrated rats because it presents hydrophenolic radicals in its molecule, thus acting as an antioxidant in this experimental model.

Protection of estrogen in portal hypertension gastropathy: an experimental model.

Science.gov (United States)

Morgan-Martins, Maria Isabel; Jacques, Simone Iahnig; Hartmann, Renata Minuzzo; Marques, Camila Moraes; Marroni, Cláudio Augusto; Marroni, Norma Possa

2011-01-01

Portal hypertension is a complication secondary to cirrhosis that is characterized by increased blood flow and/or vascular resistance in the portal system, causing the appearance of a hyperdynamic collateral circulation. Partial portal vein ligation is an experimental model used in rats to study the pathophysiological mechanisms involved in pre-hepatic portal hypertension. Estrogen E2 is an antioxidant molecule with various physiological actions. To evaluate the antioxidant activity of endogenous estrogen in an experimental model of partial portal vein ligation by comparing intact with castrated rats. Twenty Wistar rats, weighing on average 250 g were used and divided into four groups: sham-operated (SO); intact (I) with partial portal vein ligation (I + PPVL), castrated (C) and castrated with partial ligation of the vein (C + PPVL). Day 1: castration or sham-operation; day 7, PPVL surgery; on day 15 post-PPVL, portal pressure in the mesenteric vein of rats was measured on polygraph Letica. Lipid peroxidation in the stomach was assessed using the technique of thiobarbituric acid reactive substances and activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase. Statistical analysis was done with ANOVA - Student-Newman-Keuls (mean ± SE), and P<0.05 was considered as significant. Portal pressure was significantly increased in C + PPVL as compared to the other groups. There was no significant difference in the group of intact rats. TBARS showed significant damage in C and C + PPVL in relation to others. Antioxidant enzymes were significantly increased in the castrated rats with subsequent PPVL as compared to the other groups. We suggest that estrogen E2 plays a protective role in intact compared with castrated rats because it presents hydrophenolic radicals in its molecule, thus acting as an antioxidant in this experimental model.

The Short-Term Effects of Balloon-Occluded Retrograde Transvenous Obliteration, for Treating Gastric Variceal Bleeding, on Portal Hypertensive Changes: a CT Evaluation

International Nuclear Information System (INIS)

Cho, Sung Ki; Shin, Sung Wook; Yoo, Eun Young; Do, Young Soo; Park, Kwang Bo; Choo, Sung Wook; Choo, In Wook; Han, Heon

2007-01-01

We wanted to evaluate the short-term effects of balloon-occluded retrograde transvenous obliteration (BRTO) for treating gastric variceal bleeding, in terms of the portal hypertensive changes, by comparing CT scans. We enrolled 27 patients who underwent BRTO for gastric variceal bleeding and they had CT scans performed just before and after BRTO. The pre- and post-procedural CT scans were retrospectively compared by two radiologists working in consensus to evaluate the short-term effects of BRTO on the subsequent portal hypertensive changes, including ascites, splenomegaly, portosystemic collaterals (other than gastrorenal shunt), the gall bladder (GB) edema and the intestinal wall edema. Statistical differences were analyzed using the Wilcoxon signed rank test and the paired t-test. Following BRTO, ascites developed or was aggravated in 22 (82%) of 27 patients and it was improved in two patients; the median spleen volumes increased from 438.2 cm 3 to 580.8 cm 3 , and based on a 15% volume change cutoff value, splenic enlargement occurred in 15 (56%) of the 27 patients. The development of new collaterals or worsening of existing collaterals was not observed in any patient. GB wall edema developed or was aggravated in four of 23 patients and this disappeared or improved in five; intestinal wall edema developed or was aggravated in nine of 27 patients, and this disappeared or improved in five. Statistically, we found significant differences for ascites and the splenic volumes before and after BRTO (p = 0.001 and p < 0.001, respectively). Some portal hypertensive changes, including ascites and splenomegaly, can be aggravated shortly after BRTO

Dynamic CT and MRA findings of a case of portopulmonary venous anastomosis (PPVA) in a patient with portal hypertension: a case report and review of the literature

International Nuclear Information System (INIS)

Ko, Jeong Min; Ahn, Myeong Im; Han, Dae Hee; Jung, Jung Im; Park, Seog Hee

2011-01-01

Portopulmonary venous anastomosis (PPVA), which has been rarely reported in conventional CT and MR studies, is an unusual collateral pathway in patients with portal hypertension. It has clinical implications related to right-to-left shunt that are different from the clinical implications related to other more usual portosystemic shunts in portal hypertensive patients. Here, we report the dynamic CT and MRA findings of a case of PPVA in a patient with portal hypertension, directly demonstrating the shunt flow from the paraesophageal varix to the left atrium via the right inferior pulmonary vein

Dynamic CT and MRA findings of a case of portopulmonary venous anastomosis (PPVA) in a patient with portal hypertension: a case report and review of the literature

Energy Technology Data Exchange (ETDEWEB)

Ko, Jeong Min; Ahn, Myeong Im; Han, Dae Hee; Jung, Jung Im; Park, Seog Hee (Dept. of Radiology, Seoul St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of)), email: ami@catholic.ac.kr

2011-06-15

Portopulmonary venous anastomosis (PPVA), which has been rarely reported in conventional CT and MR studies, is an unusual collateral pathway in patients with portal hypertension. It has clinical implications related to right-to-left shunt that are different from the clinical implications related to other more usual portosystemic shunts in portal hypertensive patients. Here, we report the dynamic CT and MRA findings of a case of PPVA in a patient with portal hypertension, directly demonstrating the shunt flow from the paraesophageal varix to the left atrium via the right inferior pulmonary vein

Very Early Presentation of Extrahepatic Portal Vein Obstruction Causing Portal Hypertension in an Infant: Uncertainties in the Management and Therapeutic Limitations

Directory of Open Access Journals (Sweden)

Parisá Khodayar-Pardo

2016-07-01

Full Text Available Extrahepatic portal vein obstruction, although rare in children, is a significant cause of portal hypertension (PHT leading to life-threatening gastrointestinal bleeding in the pediatric age group. PHT may also lead to other complications such as hyperesplenism, cholangyopathy, ascites, and even hepatopulmonary syndrome and portopulmonary hypertension that may require organ transplantation. Herein we report the case of an asymptomatic 11-month-old infant wherein a hepatomegaly and cavernous transformation of the portal vein was detected by liver ultrasound. Neither signs of thrombosis in arteriovenous system, nor affectation of biliary tract were identified in the magnetic resonance imaging study. A significant enlargement of the caudate lobe of the liver was reported. No risk factors were detected. The differential diagnosis performed was extensive. Inherited thrombophilia and storage disorders were especially considered. Liver biopsy was normal. Upper gastrointestinal esophagogastroduodenoscopy detected two small varicose cords on the distal third of the esophagus. Finding a cavernous transformation of the portal vein with evidence of collateral circulation in such an early age is a challenging condition for professionals, since PHT may lead to severe complications during childhood and can compromise growth and development. Evidence-based guidelines for the management of PHT in adults have been published. However, follow-up and treatment of pediatric patients have not yet been standardized. Moreover, management of PHT in infants faces particular difficulties such as technical restrictions that could hinder their treatment.

24 CFR 330.10 - Eligible collateral.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Eligible collateral. 330.10 Section... SECURITIES § 330.10 Eligible collateral. The Association, in its discretion, shall determine what collateral is eligible for inclusion in the Multiclass Securities program. Eligible collateral may include GNMA...

On line portal imaging

International Nuclear Information System (INIS)

Munro, Peter

1997-01-01

difficulties, many image registration techniques such as interactive techniques, landmark-based techniques, contrast-based techniques, and hybrid techniques have been developed to detect errors in patient positioning. The advantages and disadvantages of these various techniques will be discussed. Clinical use of portal imaging systems has included the use of static localisation and verification images, the use of 'movie' sequences (sequences of images acquired during one irradiation) and the use of 'time-lapse' sequences of images acquired during consecutive treatments, which demonstrate the variability in patient set-up over a full course of therapy. Possibly the most contentious issue is how to best make use of the information provided the portal images. Philosophies have ranged between intervening in every treatment, to intervening only occasionally, or to identifying patients who would benefit from smaller treatment margins and modifying the treatment plan part way through the course of treatment. The different approaches and the technological developments needed for some of the approaches will be discussed. CONCLUSIONS: While great improvements in portal imaging technology have been made, in the future more effort will be directed towards improving image quality, and integrating and automating the various steps in the image registration process. Most effort needs to be aimed at reducing the time required to measure the geometric discrepancies in the portal images and to intervene in the treatment. Only when portal imaging can be used for immediate feedback about patient positioning can it make a difference in the accuracy of radiation treatments

7 CFR 1779.48 - Collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false Collateral. 1779.48 Section 1779.48 Agriculture... (CONTINUED) WATER AND WASTE DISPOSAL PROGRAMS GUARANTEED LOANS § 1779.48 Collateral. (a) Lender responsibility. The lender is responsible for obtaining and maintaining proper and adequate collateral to protect...

Therapeutic effects of percutaneous transhepatic variceal embolization combined with partial splenic embolization for portal hypertention

International Nuclear Information System (INIS)

Hua Yingxue; Yan Zhiping; Cheng Yongde; Qiao Delin; Zhou Bing; Chen Shiwei; Li Yong

2007-01-01

Objective: To evaluate the efficiency of percutaneous transhepatic variceal embolization (PTVE) combined with patial splenic embolization (PES)for portal hypertension. Methods: 30 patients with critical portal hypertension were divided randomly into two groups, 15 patients of A group underwent PSE PTVE combined with PSE and 15 of B group underwent PES only. The changes of collateral circulation of the two groups were compared via color Doppler ultrasonography pre-and postoperatively. Results: The hypersplenism was well controlled in both groups after PTVE and PSE. The varices of A group were embolized completely, the flow rate and velocity of portal blood stream were significantly reduced (P<0.05). In addition, the flow rate and velocity together with inner diameter of the azygous vein decreased (P<0.01), but no change shown on portal vein diameter, only with decrease of blood flow and velocity postoperatively were shown in the two groups (P<0.05). During 13-16 months follow-up, gastroesophageal variceal bleeding appeared in 2 patients and formation of portal thrombi in 1 patients of B group. There was no gastroesophageal variceal bleeding in A group but 2 patients appeared portal hypertensive gastroenteropathy (PHG)under endoscopic confirmations. Conclusion: PTVE combined PSE is very efficient for gastroesophageal variceal bleeding and hypersplenism due to portal hypertension, especially for patients with poor hepatic function, possessing simple, economic, less invasive properties and deserving to be recommended. (authors)

Heart/liver ratios and portal vein pressure used in early cirrhosis diagnosis

International Nuclear Information System (INIS)

He Jingxiang; Li Wenfan; Liu Chun; Yang Peng; Chen Ming; Wang Hong

2001-01-01

Objective: To find a method which not only can comprehensively evaluate the rise of portal pressure, opening and establishment of portal collateral circulation, portal-systemic shunting, and liver and spleen functions in cirrhosis, but also aid the differential diagnosis of early and established cirrhosis. Methods: Heart/liver count (H/L) ratios were obtained at different times after per-rectal administration of 99m Tc-MIBI. Portal venous pressures at different times were calculated using a previously documented formula. The relationship between portal venous pressure and cirrhosis, including its pathological process, was then evaluated. Results: There was obvious discrepancy (t=2.810; p<0.05) in 90-150 minutes portal venous pressures between normal and late hepatitis groups; there was also obvious difference (t=2.348, p<0.05) in portal venous pressures between the cirrhosis group and other groups. The portal venous pressure of early cirrhosis group was also significantly different (t=2.167, p<0.05) from other groups and it was situated between those of normal, and hepatitis and cirrhosis groups. There was obvious diversity (t=2.287, p<0.05) in Child-Pugh classification levels in the late imaging phase. There was positive correlation between calculated portal venous pressure and H/L ratio (r=0.487, p<0.01). Conclusion: Using temporal portal venous recirculation imaging, an early H/L ratio of ≥0.65 and formula-calculated portal venous pressure of ≥1.9 kPa or a portal-systemic venous pressure difference of ≥1.5 kPa indicate cirrhosis; H/L ratio between 0.32 and 0.64 or portal venous pressure between 1.03 to 1.89 kPa suggest early cirrhosis. Our study showed that H/L ratios at specific times and computed portal vein pressure might be important in the diagnosis of hepatitis, impaired hepatic function caused by cirrhosis, portal-systemic shunting, and portal venous recirculation. It is a simple, sensitive, reliable, and non-invasive method, which can be helpful in

Standardization of MIP technique in three-dimensional CT portography: usefulness in evaluation of portosystemic collaterals in cirrhotic patients

International Nuclear Information System (INIS)

Kim, Jong Gi; Kim, Yong; Kim, Chang Won; Lee, Jun Woo; Lee, Suk Hong

2003-01-01

To assess the usefulness of three-dimensional CT portography using a standardized maximum intensity projection (MIP) technique for the evaluation of portosystemic collaterals in cirrhotic patients. In 25 cirrhotic patients with portosystemic collaterals, three-phase CT using a multide-tector-row helical CT scanner was performed to evaluate liver disease. Late arterial-phase images were transferred to an Advantage Windows 3.1 workstation (Gener Electric). Axial images were reconstructed by means of three-dimensional CT portography, using both a standardized and a non-standardized MIP technique, and the respective reconstruction times were determined. Three-dimensional CT portography with the standardized technique involved eight planes, namely the spleno-portal confluence axis (coronal, lordotic coronal, lordotic coronal RAO 30 .deg. C, and lordotic coronal LAO 30 .deg. C), the left renal vein axis (lordotic coronal), and axial MIP images (lower esophagus level, gastric fundus level and splenic hilum). The eight MIP images obtained in each case were interpreted by two radiologists, who reached a consensus in their evaluation. The portosystemic collaterals evaluated were as follows: left gastric vein dilatation; esophageal, paraesophageal, gastric, and splenic varix; paraumbilical vein dilatation; gastro-renal, spleno-renal, and gastro-spleno-renal shunt; mesenteric, retroperitoneal, and omental collaterals. The average reconstruction time using the non-standardized MIP technique was 11 minutes 23 seconds, and with the standardized technique, the time was 6 minutes 5 seconds. Three-dimensional CT portography with the standardized technique demonstrated left gastric vein dilatation (n=25), esophageal varix (n=18), paraesophageal varix (n=13), gastric varix (n=4), splenic varix (n=4), paraumbilical vein dilatation (n=4), gastro-renal shunt (n=3), spleno-renal shunt (n=3), and gastro-spleno-renal shunt (n=1). Using three-dimensional CT protography and the non

On line portal imaging

International Nuclear Information System (INIS)

Munro, Peter

1996-01-01

is finding a common frame of reference for the simulator and portal images, since the location of the radiation field within the pixel matrix may differ for the two images. This problem is compounded by the fact that the commercially available EPIDs have mechanical slop and do not deploy to exactly the same position repeatedly. As a result, a common frame of reference has to be established before the anatomic structures in the images can be registered - generally by registering radiation field edges identified in the simulator and portal images. In addition, distortions in patient geometry or rotations out of the image plane can confound the image registration techniques. Despite the difficulties, many image registration techniques such as interactive techniques, landmark-based techniques, contrast-based techniques, and hybrid techniques have been developed to detect errors in patient positioning. The advantages and disadvantages of these various techniques will be discussed. Clinical use of portal imaging systems has included the use of static localisation and verification images, the use of 'movie' sequences (sequences of images acquired during one irradiation) and the use of 'time-lapse' sequences of images acquired during consecutive treatments, which demonstrate the variability in patient set-up over a full course of therapy. Possibly the most contentious issue is how to best make use of the information provided the portal images. Philosophies have ranged between intervening in every treatment, to intervening only occasionally, or to identifying patients who would benefit from smaller treatment margins and modifying the treatment plan part way through the course of treatment. Conclusions: While great improvements in portal imaging technology have been made, in the future more effort will to be directed towards improving image quality, and integrating and automating the various steps in the image registration process. In addition, other uses for portal imaging

13 CFR 120.934 - Collateral.

Science.gov (United States)

2010-01-01

... Loan Program (504) 504 Loans and Debentures § 120.934 Collateral. The CDC usually takes a second lien position on the Project Property to secure the 504 loan. Sometimes additional collateral is required. (In... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Collateral. 120.934 Section 120...

An automated portal verification system for the tangential breast portal field

International Nuclear Information System (INIS)

Yin, F.-F.; Lai, W.; Chen, C. W.; Nelson, D. F.

1995-01-01

Purpose/Objective: In order to ensure the treatment is delivered as planned, a portal image is acquired in the accelerator and is compared to the reference image. At present, this comparison is performed by radiation oncologists based on the manually-identified features, which is both time-consuming and potentially error-prone. With the introduction of various electronic portal imaging devices, real-time patient positioning correction is becoming clinically feasible to replace time-delayed analysis using films. However, this procedure requires present of radiation oncologists during patient treatment which is not cost-effective and practically not realistic. Therefore, the efficiency and quality of radiation therapy could be substantially improved if this procedure can be automated. The purpose of this study is to develop a fully computerized verification system for the radiation therapy of breast cancer for which a similar treatment setup is generally employed. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature correlation between reference and portal images, and quantitative evaluation of patient setup. In this study, a matrix liquid ion-chamber EPID was used to acquire digital portal images which is directly attached to Varian CL2100C accelerator. For effective use of computation memory, the 12-bit gray levels in original portal images were quantized to form a range of 8-bit gray levels. A typical breast portal image includes three important components: breast and lung tissues in the treatment field, air space within the treatment field, and non-irradiated region. A hierarchical region processing technique was developed to separate these regions sequentially. The inherent hierarchical features were formulated based on different radiation attenuation for different regions as: treatment field edge -- breast skin line -- chest wall. Initially, a combination of a Canny edge detector and a constrained

Reexamining the empirical relation between loan risk and collateral: The roles of collateral characteristics and types

OpenAIRE

Berger, Allen N.; Frame, Scott; Ioannidou, Vasso

2011-01-01

This paper offers a possible explanation for the conflicting empirical results in the literature concerning the relation between loan risk and collateral. Specifically, we posit that different economic characteristics or types of collateral pledges may be associated with the empirical dominance of the four different risk-collateral channels implied by economic theory. For our sample, collateral overall is associated with lower loan risk premiums and a higher probability of ex post loan nonper...

The dynamics of the coronary collateral circulation.

Science.gov (United States)

Zimarino, Marco; D'Andreamatteo, Mariangela; Waksman, Ron; Epstein, Stephen E; De Caterina, Raffaele

2014-04-01

Coronary collaterals are present at birth, with wide interindividual variation in their functional capacity. These vessels protect jeopardized myocardium, and the number of collaterals and the extent of their coverage are associated with improved survival in patients with coronary heart disease. The collateral circulation is not a permanent set of structures, but undergoes dynamic changes with important consequences for cardioprotection. If a severe atherosclerotic lesion develops in an artery supplying tissue downstream of a total occlusion through collateral blood flow, pressure gradients across the collateral bed change. The result is that some of the collateral flow previously supplying the perfusion territory of the totally occluded artery is redirected to the perfusion territory of the donor artery, thus producing a 'collateral steal'. The collateral circulation can regress once antegrade flow in the main dependent artery is re-established, as occurs following the recanalization of a chronic total occlusion. The clinical benefits of coronary revascularization must be cautiously weighed against the risk of reducing the protective support derived from coronary collaterals. Consequently, pharmacological, gene-based, and cell-based therapeutic attempts have been made to enhance collateral function. Although such approaches have so far yielded no, or modest, beneficial results, the rapidly accruing data on coronary collateral circulation will hopefully lead to new effective therapeutic strategies.

12 CFR 950.7 - Collateral.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral. 950.7 Section 950.7 Banks and... Advances to Members § 950.7 Collateral. (a) Eligible security for advances to all members. At the time of... interest in collateral that meets the requirements of one or more of the following categories: (1) Mortgage...

Ulnar Collateral Ligament Injuries of the Thumb

Science.gov (United States)

McKeon, Kathleen E.; Gelberman, Richard H.; Calfee, Ryan P.

2013-01-01

Background: The clinical diagnosis of thumb ulnar collateral ligament disruption has been based on joint angulation during valgus stress testing. This report describes a definitive method of distinguishing between complete and partial ulnar collateral ligament injuries by quantifying translation of the proximal phalanx on the metacarpal head during valgus stress testing. Methods: Sixty-two cadaveric thumbs underwent standardized valgus stress testing under fluoroscopy with the ulnar collateral ligament intact, following an isolated release of the proper ulnar collateral ligament, and following a combined release of both the proper and the accessory ulnar collateral ligament (complete ulnar collateral ligament release). Following complete ulnar collateral ligament release, the final thirty-seven thumbs were also analyzed after the application of a valgus force sufficient to cause 45° of valgus angulation at the metacarpophalangeal joint to model more severe soft-tissue injury. Two independent reviewers measured coronal plane joint angulation (in degrees), ulnar joint line gap formation (in millimeters), and radial translation of the proximal phalanx on the metacarpal head (in millimeters) on digital fluoroscopic images that had been randomized. Results: Coronal angulation across the stressed metacarpophalangeal joint progressively increased through the stages of the testing protocol: ulnar collateral ligament intact (average [and standard deviation], 20° ± 8.1°), release of the proper ulnar collateral ligament (average, 23° ± 8.3°), and complete ulnar collateral ligament release (average, 30° ± 8.9°) (p collateral ligament release (5.7 ± 1.5 mm), to that following complete ulnar collateral ligament release (7.2 ± 1.5 mm) (p collateral ligament (1.6 ± 0.8 mm vs. 1.5 ± 0.9 mm in the intact state). There was a significant increase in translation following release of the complete ulnar collateral ligament complex (3.0 ± 0.9 mm; p collateral ligament

Lateral collateral ligament (image)

Science.gov (United States)

The lateral collateral ligament connects the end of the femur (thigh) to the top of the fibula (the thin bone that runs next to the shin bone). The lateral collateral ligament provides stability against varus stress. Varus stress ...

Perivesical varices and portal hypertension: imaging study; Varices perivesiculares e hipertension postal. Estudio por imagen

Energy Technology Data Exchange (ETDEWEB)

Mallorquin Jimenez, F; Medina Benitez, A; Lopez Machado, E; Pardo Moreno, M D; Garrido Moreno, C; Pastor Rull, J [Servicio de Radiodiagnostico, Hospital General de Especialidades Virgen de la Nieve, Granada (Spain)

1995-07-01

Nine patients with portal hypertension syndrome and Perivesical varices are studied retrospectively by means of imaging techniques including ultrasound, duplex Doppler, color Doppler, CT and angiography. All the patients presented portal thrombosis and thickening of the bladder wall. These collaterals either represent a shunting of hepato pedal flow or correspond to blood stasis associated with said syndrome. Ultrasound, whether involving duplex Doppler or color Doppler techniques, is highly useful to detect the presence of Perivesical varices which appear as tubular or rounded hypo echogenic areas in the bladder wall. Given the association of this entity with bladder wall thickening, it should be taken into account in any clinical situation involving said change, especially in patients with portal hypertension; moreover knowledge of its presence is of great importance when the possibility of creating shunts by means of interventional or surgical vascular procedures or other types of abdominal procedures are being considered because of the risk of bleeding. (Author)

12 CFR 950.10 - Collateral valuation; appraisals.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral valuation; appraisals. 950.10...-BALANCE SHEET ITEMS ADVANCES Advances to Members § 950.10 Collateral valuation; appraisals. (a) Collateral valuation. Each Bank shall determine the value of collateral securing the Bank's advances in accordance with...

12 CFR 615.5060 - Special collateral requirement.

Science.gov (United States)

2010-01-01

... AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Collateral § 615.5060 Special collateral... be withdrawn from collateral upon the expiration of 1 year from the date of the loan closing, unless... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Special collateral requirement. 615.5060...

A Framework for Collateral Risk Control Determination

OpenAIRE

Didier Cossin; Zhijiang Huang; Daniel Aunon-Nerin; Fer nando González

2002-01-01

This paper derives a general framework for collateral risk control determination in repurchase transactions or repos. The objective is to treat consistently heterogeneous collateral so that the collateral taker has a similar risk exposure whatever the collateral pledged. The framework measures the level of risk with the probability of incurring a loss higher than a pre-specified level given two well-known parameters used to manage the intrinsic risk of collateral: marking to market and haircu...

27 CFR 17.104 - Deposit of collateral.

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2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Deposit of collateral. 17... PRODUCTS Bonds and Consents of Sureties § 17.104 Deposit of collateral. Except as otherwise provided by law... as collateral security in lieu of bonds obtained from surety companies. Deposit of collateral...

7 CFR 4287.113 - Release of collateral.

Science.gov (United States)

2010-01-01

... Loans § 4287.113 Release of collateral. (a) All releases of collateral with a value exceeding $100,000... loan. The Agency may, at its discretion, require an appraisal of the remaining collateral in cases... (a) of this section, lenders may, over the life of the loan, release collateral (other than personal...

The Future of Collateral Artery Research

Science.gov (United States)

Hakimzadeh, Nazanin; Verberne, Hein J.; Siebes, Maria; Piek, Jan J.

2014-01-01

In the event of obstructive coronary artery disease, collateral arteries have been deemed an alternative blood source to preserve myocardial tissue perfusion and function. Monocytes play an important role in modulating this process, by local secretion of growth factors and extracellular matrix degrading enzymes. Extensive efforts have focused on developing compounds for augmenting the growth of collateral vessels (arteriogenesis). Nonetheless, clinical trials investigating the therapeutic potential of these compounds resulted in disappointing outcomes. Previous studies focused on developing compounds that stimulated collateral vessel growth by enhancing monocyte survival and activity. The limited success of these compounds in clinical studies, led to a paradigm shift in arteriogenesis research. Recent studies have shown genetic heterogeneity between CAD patients with sufficient and insufficient collateral vessels. The genetic predispositions in patients with poorly developed collateral vessels include overexpression of arteriogenesis inhibiting signaling pathways. New directions of arteriogenesis research focus on attempting to block such inhibitory pathways to ultimately promote arteriogenesis. Methods to detect collateral vessel growth are also critical in realizing the therapeutic potential of newly developed compounds. Traditional invasive measurements of intracoronary derived collateral flow index remain the gold standard in quantifying functional capacity of collateral vessels. However, advancements made in hybrid diagnostic imaging modalities will also prove to be advantageous in detecting the effects of pro-arteriogenic compounds. PMID:23638829

29 CFR 20.32 - Liquidation of collateral.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Liquidation of collateral. 20.32 Section 20.32 Labor Office... collateral. An agency holding security or collateral which may be liquidated and the proceeds applied on... demand, unless the cost of disposing of the collateral will be disproportionate to its value or special...

25 CFR 502.5 - Collateral agreement.

Science.gov (United States)

2010-04-01

... 25 Indians 2 2010-04-01 2010-04-01 false Collateral agreement. 502.5 Section 502.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.5 Collateral agreement. Collateral agreement means any contract, whether or not in writing...

30 CFR 800.21 - Collateral bonds.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Collateral bonds. 800.21 Section 800.21 Mineral... FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral bonds. (a) Collateral bonds, except for letters of credit, cash accounts, and real property, shall be...

Effects on growth after hypertension portal induced in young rats Efeitos da hipertensão portal sobre o crescimento de ratos jovens

Directory of Open Access Journals (Sweden)

Luiz Eduardo Correia Miranda

2004-03-01

Full Text Available BACKGROUND: Physical growth retardation in children with hypertension portal was observed regardless of schistosomiasis. It has been suggested that the shunt of portal blood through portosystemic collateral vessels would result in metabolic consequences that would lead to the physical growth deficit observed. AIM: Study the effects of hypertension portal in the growth of young rats. METHODS: The growth of 20 young rats, divided in the groups hypertension portal, n = 10, 103 3.7 g and sham operation n = 10, 102.6 ± 3.4 g was evaluated throughout 5 weeks and the following parameters were under observation: quality of diet offered, diet ingestion, weight increase and urinary creatinine within 24 hours. At the end of the experiment, blood was taken for biochemical tests, prothrombin time and hematocrit and hypertension portal was measured. RESULTS/CONCLUSIONS: Rats with hypertension portal induced at early stages of their lives present growth delay in the first week after surgery recovering their growth rhythm in the next weeks, catching up with the sham animals. Differences related to urinary creatinine excretion, biochemical tests and hematocrit were not observed. Such results are evidence against the hypothesis that the hypertension portal induced in early stages of rats lives would cause delay in their growth.RACIONAL: Atraso no crescimento foi observado em crianças com hipertensão portal independentemente da presença de esquistossomose. Sugeriu-se que o desvio de sangue pelas colaterais portossistêmicas justificaria os achados clínicos encontrados. OBJETIVO: Estudar os efeitos da hipertensão portal no crescimento de ratos jovens. MÉTODOS: O crescimento de 20 ratos divididos nos grupos hipertensão portal n = 10, 103 ± 3,7 g e grupo-controle, n = 10, 102,6 ± 3,4 g foi avaliado durante 5 semanas. Foram considerados a qualidade da dieta oferecida, a ingestão da dieta, o ritmo de crescimento ganho de peso, a excreção de creatinina urin

Sex Differences in the Cerebral Collateral Circulation.

Science.gov (United States)

Faber, James E; Moore, Scott M; Lucitti, Jennifer L; Aghajanian, Amir; Zhang, Hua

2017-06-01

Premenopausal women and intact female rodents sustain smaller cerebral infarctions than males. Several sex-dependent differences have been identified as potential contributors, but many questions remain unanswered. Mice exhibit wide variation in native collateral number and diameter (collateral extent) that is dependent on differences in genetic background, aging, and other comorbidities and that contributes to their also-wide differences in infarct volume. Likewise, variation in infarct volume correlates with differences in collateral-dependent blood flow in patients with acute ischemic stroke. We examined whether extent of pial collateral arterioles and posterior communicating collateral arteries (PComAs) differ depending on sex in young, aged, obese, hypertensive, and genetically different mice. We combined new data with meta-analysis of our previously published data. Females of C57BL/6J (B6) and BALB/cByJ (BC) strains sustained smaller infarctions than males after permanent MCA occlusion. This protection was unchanged in BC mice after introgression of the B6 allele of Dce1, the major genetic determinant of variation in pial collaterals among mouse strains. Consistent with this, collateral extent in these and other strains did not differ with sex. Extent of PComAs and primary cerebral arteries also did not vary with sex. No dimorphism was evident for loss of pial collateral number and/or diameter (collateral rarefaction) caused by aging, obesity, and hypertension, nor for collateral remodeling after pMCAO. However, rarefaction was greater in females with long-standing hypertension. We conclude that smaller infarct volume in female mice is not due to greater collateral extent, greater remodeling, or less rarefaction caused by aging, obesity, or hypertension.

28 CFR 94.25 - Collateral sources.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Collateral sources. 94.25 Section 94.25... Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of expenses... collateral source in connection with the same act of international terrorism. In cases in which a claimant...

12 CFR 615.5050 - Collateral requirements.

Science.gov (United States)

2010-01-01

... provided in this paragraph, the collateral value of notes and other obligations representing loans made... allowance for loan losses (except as provided for in § 615.5090). (2) The collateral value of loans in... loans, judgments, and contracts adjusted for any allowance for losses. (3) The collateral value of loans...

Research advances in computed tomography and magnetic resonance imaging findings of cirrhotic portal hypertension

Directory of Open Access Journals (Sweden)

YAN Fuhua

2016-06-01

Full Text Available Portal hypertension is the most common complication of liver cirrhosis. Noninvasive radiological examinations have important values in evaluating liver parenchyma, collateral circulation, and esophagogastric variceal bleeding in liver cirrhosis. Computed tomography (CT and magnetic resonance imaging (MRI can reflect the changes in liver morphology, the density and signals of liver parenchyma, and hemodynamics and have important values in disease diagnosis and prognostic evaluation. CT and functional MRI, such as perfusion-weighted imaging, MR elastography, and MR diffusion-weighted imaging, can provide quantitative information and can be applied in the diagnosis of hepatic fibrosis and early-stage liver cirrhosis in clinical practice. CT angiography and MR angiography, especially unenhanced MR angiography, can show the condition of the branches of portal vein, which helps to evaluate the risk of esophagogastric variceal bleeding and detect the markers for early warning. A combination of CT and MRI and evaluation of their potential in clinical application can give full play to the role of radiological examinations in the diagnosis, evaluation, and prognostic analysis of cirrhotic portal hypertension.

Military Robotics and Collateral Damage

National Research Council Canada - National Science Library

Kott, Robert Douglass ;Alexander

2004-01-01

.... Such concepts raise important questions in terms of their impact on collateral damage. In a broader context, western warfare in general places a continuously growing emphasis on issues of collateral damage...

Effects of raloxifene on portal hypertension and hepatic encephalopathy in cirrhotic rats.

Science.gov (United States)

Chang, Ching-Chih; Lee, Wen-Shin; Chuang, Chiao-Lin; Hsin, I-Fang; Hsu, Shao-Jung; Chang, Ting; Huang, Hui-Chun; Lee, Fa-Yauh; Lee, Shou-Dong

2017-05-05

Raloxifene, a selective estrogen receptor modulator, has been used extensively for osteoporosis. In addition to the effect of osteoporosis treatment, emerging evidences show that raloxifene affects the vascular function in different tissues. Cirrhosis is characterized with portal hypertension and complicated with hepatic encephalopathy. Portal hypertension affects portal-systemic shunt which leads to hepatic encephalopathy that the vascular modulation might influence severity of hepatic encephalopathy. Herein, we evaluated the impact of raloxifene on bile duct ligation (BDL)-induced cirrhotic rats. The female Sprague-Dawley rats received BDL plus ovariectomy or sham-operation. Four weeks later, rats were divided into 2 subgroups respectively to receive of raloxifene (10mg/kg/day) or saline (vehicle) for 14 days. On the 43th day, motor activities and hemodynamic parameters were measured. Hepatic and vascular mRNA and protein expressions were determined. The histopathological change of liver was examined. We found that the liver biochemistry, ammonia level and motor activity were similar between cirrhotic rats with or without raloxifene administration. The hemodynamic parameters were not significantly different except that raloxifene reduced portal venous inflow. Raloxifene exacerbated hepatic fibrosis and up-regulated hepatic endothelin-1 and cyclooxygenase 2 protein expressions. In addition, raloxifene modulated the mRNA expressions of endothelial nitric oxide synthase, cyclooxygenase and endothelin-1 in the superior mesenteric artery and collateral vessel. In conclusion, raloxifene aggravates hepatic fibrosis and decreases portal venous inflow in cirrhotic rats without adversely affecting portal hypertension and hepatic encephalopathy. The modulation of hepatic and vascular endothelin-1, endothelial nitric oxide synthase and cyclooxygenase expressions may play a role in the mechanism. Copyright © 2017 Elsevier B.V. All rights reserved.

On line portal imaging

International Nuclear Information System (INIS)

Munro, Peter

1995-01-01

structures on a digitized simulator film. Once the anatomic structures have been registered, any discrepancies in the position of the patient can be identified. However, the task is not nearly as straight-forward as it sounds. One problem is finding a common frame of reference for the simulator and portal images, since the location of the radiation field within the pixel matrix may differ for the two images. This problem is compounded by the fact that the commercially available EPIDs have mechanical slop and do not deploy to exactly the same position repeatedly. As a result, a common frame of reference has to be established before the anatomic structures in the images can be registered - generally by registering radiation field edges identified in the simulator and portal images. In addition, distortions in patient geometry or rotations out of the image plane can confound the image registration techniques. Despite the difficulties, many image registration techniques such as interactive techniques, landmark-based techniques, contrast-based techniques, and hybrid techniques have been developed to detect errors in patient positioning. The advantages and disadvantages of these various techniques will be discussed. Clinical use of portal imaging systems has included the use of static localisation and verification images, the use of 'movie' sequences (sequences of images acquired during one irradiation) and the use of 'time-lapse' sequences of images acquired during consecutive treatments, which demonstrate the variability in patient set-up over a full course of therapy. Possibly the most contentious issue is how to best make use of the information provided the portal images. Philosophies have ranged between intervening in every treatment, to intervening only occasionally, or to identifying patients who would benefit from smaller treatment margins and modifying the treatment plan part way through the course of treatment. While great improvements in portal imaging technology have

Understanding Collateral Evolution in Linux Device Drivers

DEFF Research Database (Denmark)

Padioleau, Yoann; Lawall, Julia Laetitia; Muller, Gilles

2006-01-01

no tools to help in this process, collateral evolution is thus time consuming and error prone.In this paper, we present a qualitative and quantitative assessment of collateral evolution in Linux device driver code. We provide a taxonomy of evolutions and collateral evolutions, and use an automated patch......-analysis tool that we have developed to measure the number of evolutions and collateral evolutions that affect device drivers between Linux versions 2.2 and 2.6. In particular, we find that from one version of Linux to the next, collateral evolutions can account for up to 35% of the lines modified in such code....

Portographic Evaluation for Recurrent Esophagogastric Varices Following Devascularization Surgery

International Nuclear Information System (INIS)

Hsieh, J.-S.; Huang, C.-J.; Wang, J.-Y.; Huang, T.-J.

1996-01-01

Purpose: To investigate, by transhepatic portography, the changes in portosystemic collaterals and recurrent esophagogastric varices after devascularization surgery. Methods: Thirty-five patients, who had undergone devascularization surgery 2 - 8 years previously, underwent follow-up portography and the collaterals and drainage routes were compared with preoperative portography results. Results: Newly formed collaterals were present in 30 of 35 patients and the origins and drainage routes differed from preoperative ones. Most common were new collaterals arising from the junction of the portal and superior mesenteric veins; the next most frequent arose from a main portal branch, the portal trunk, or the superior mesenteric vein. New collaterals with recurrent varices were seen in 20 patients and without varices in 10; 5 patients had no collaterals or varices.Conclusion: Since the development of new collaterals is common in portal hypertensive patients following devascularization surgery, regular follow-up for recurrent varices is necessary

Reexamining the empirical relation between loan risk and collateral:the roles of collateral liquidity and types

OpenAIRE

Berger, Allen N.; Frame, W. Scott; Ioannidou, Vasso

2016-01-01

This paper offers a possible explanation for the conflicting results in the literature concerning the empirical relation between collateral and loan risk. We posit that differences in collateral characteristics, such as liquidity, may be associated with the empirical dominance of different risk-collateral relations implied by economic theory. Using credit registry data and a novel identification strategy to control for borrower and lender selection effects allows us to differentiate between t...

How Collateral Laws Shape Lending and Sectoral Activity

OpenAIRE

Calomiris, Charles W.; Larrain, Mauricio; Liberti, José; Sturgess, Jason

2015-01-01

This paper investigates the effect of cross-country differences in collateral laws regarding movable assets on lending and sectoral allocation of resources. Using micro-level loan data for a sample of emerging market countries we show that loan-to-values of loans collateralized with movable assets are on average 21 percentage points higher in countries with strong-collateral laws relative to immovable assets. Further, stronger collateral laws tilt collateral composition away from immovable to...

Change in the collateral and accessory collateral ligament lengths of the proximal interphalangeal joint using cadaveric model three-dimensional laser scanning.

Science.gov (United States)

Sandhu, S S; Dreckmann, S; Binhammer, P A

2016-05-01

The purpose of this study was to assess the lengths of the index and middle finger proximal interphalangeal joint ligaments and determine the relative changes in the collateral and accessory collateral ligament lengths at 0°, 45° and 90° flexion. We generated three-dimensional scans of 16 finger (eight index and eight middle) proximal interphalangeal joints to assess relative changes in ligament length. Significant changes were found between 45°-90° and 0°-90° for the ulnar collateral ligament of the index finger and both collateral ligaments of the middle finger between 45°-90° and 0°-90°. No significant changes in length were found for the radial collateral ligament of the index finger or the accessory collateral ligaments of the index and middle fingers. Overall, it was found that the collateral ligament length changed significantly, but there was no significant change in the accessory collateral ligaments. Therapeutic IV. © The Author(s) 2015.

27 CFR 24.159 - Release of collateral security.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Release of collateral... § 24.159 Release of collateral security. Collateral security pledged and deposited will be released only in accordance with the provisions of 31 CFR part 225. The collateral security will not be released...

Abnormal splenic artery diameter/hepatic artery diameter ratio in cirrhosis-induced portal hypertension

Science.gov (United States)

Zeng, Dao-Bing; Dai, Chuan-Zhou; Lu, Shi-Chun; He, Ning; Wang, Wei; Li, Hong-Jun

2013-01-01

AIM: To determine an optimal cutoff value for abnormal splenic artery diameter/proper hepatic artery diameter (S/P) ratio in cirrhosis-induced portal hypertension. METHODS: Patients with cirrhosis and portal hypertension (n = 770) and healthy volunteers (n = 31) underwent volumetric computed tomography three-dimensional vascular reconstruction to measure the internal diameters of the splenic artery and proper hepatic artery to calculate the S/P ratio. The cutoff value for abnormal S/P ratio was determined using receiver operating characteristic curve analysis, and the prevalence of abnormal S/P ratio and associations between abnormal S/P ratio and major complications of portal hypertension were studied using logistic regression. RESULTS: The receiver operating characteristic analysis showed that the cutoff points for abnormal splenic artery internal diameter and S/P ratio were > 5.19 mm and > 1.40, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value were 74.2%, 45.2%, 97.1%, and 6.6%, respectively. The prevalence of an abnormal S/P ratio in the patients with cirrhosis and portal hypertension was 83.4%. Patients with a higher S/P ratio had a lower risk of developing ascites [odds ratio (OR) = 0.708, 95%CI: 0.508-0.986, P = 0.041] and a higher risk of developing esophageal and gastric varices (OR = 1.483, 95%CI: 1.010-2.175, P = 0.044) and forming collateral circulation (OR = 1.518, 95%CI: 1.033-2.230, P = 0.034). After splenectomy, the portal venous pressure and maximum and mean portal venous flow velocities were reduced, while the flow rate and maximum and minimum flow velocities of the hepatic artery were increased (P portal hypertension, and it can be used as an important marker of splanchnic hemodynamic disturbances. PMID:23483462

Cardiovascular risk factors and collateral artery formation.

Science.gov (United States)

de Groot, D; Pasterkamp, G; Hoefer, I E

2009-12-01

Arterial lumen narrowing and vascular occlusion is the actual cause of morbidity and mortality in atherosclerotic disease. Collateral artery formation (arteriogenesis) refers to an active remodelling of non-functional vascular anastomoses to functional collateral arteries, capable to bypass the site of obstruction and preserve the tissue that is jeopardized by ischaemia. Hemodynamic forces such as shear stress and wall stress play a pivotal role in collateral artery formation, accompanied by the expression of various cytokines and invasion of circulating leucocytes. Arteriogenesis hence represents an important compensatory mechanism for atherosclerotic vessel occlusion. As arteriogenesis mostly occurs when lumen narrowing by atherosclerotic plaques takes place, presence of cardiovascular risk factors (e.g. hypertension, hypercholesterolaemia and diabetes) is highly likely. Risk factors for atherosclerotic disease affect collateral artery growth directly and indirectly by altering hemodynamic forces or influencing cellular function and proliferation. Adequate collateralization varies significantly among atherosclerotic patients, some profit from the presence of extensive collateral networks, whereas others do not. Cardiovascular risk factors could increase the risk of adverse cardiovascular events in certain patients because of the reduced protection through an alternative vascular network. Likewise, drugs primarily thought to control cardiovascular risk factors might contribute or counteract collateral artery growth. This review summarizes current knowledge on the influence of cardiovascular risk factors and the effects of cardiovascular medication on the development of collateral vessels in experimental and clinical studies.

22 CFR 213.17 - Liquidation of collateral.

Science.gov (United States)

2010-04-01

... Liquidation of collateral. Where the CFO holds a security instrument with a power of sale or has physical possession of collateral, he may liquidate the security or collateral and apply the proceeds to the overdue... circumstances require judicial foreclosure. However, collection from other businesses, including liquidation of...

7 CFR 3.15 - Liquidation of collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Liquidation of collateral. 3.15 Section 3.15... and Compromise of Claims § 3.15 Liquidation of collateral. (a) In accordance with applicable statutes and regulations, agencies may liquidate security or collateral through a sale or a nonjudicial...

40 CFR 13.16 - Liquidation of collateral.

Science.gov (United States)

2010-07-01

... STANDARDS Collection § 13.16 Liquidation of collateral. Where the Administrator holds a security instrument with a power of sale or has physical possession of collateral, he may liquidate the security or... businesses, including liquidation of security or collateral, is not a prerequisite to requiring payment by a...

[Collateral score based on CT perfusion can predict the prognosis of patients with anterior circulation ischemic stroke after thrombectomy].

Science.gov (United States)

Wang, Qingsong; Zhang, Sheng; Zhang, Meixia; Chen, Zhicai; Lou, Min

2017-07-25

To evaluate the value of collateral score based on CT perfusion (CTP-CS) in predicting the clinical outcome of patients with anterior circulation ischemic stroke after thrombectomy. Clinical data of acute ischemic stroke patients with anterior artery occlusion undergoing endovascular treatment in the Second Affiliated Hospital, Zhejiang University School of Medicine during October 2013 and October 2016 were retrospectively reviewed. Collateral scores were assessed based on CTP and digital subtraction angiography (DSA) images, respectively. And DSA-CS or CTP-CS 3-4 was defined as good collateral vessels. Good clinical outcome was defined as a modified Rankin Scale (mRS) ≤ 2 at 3 months after stroke. The binary logistic regression model was used to analyze the correlation between the collateral score and clinical outcome, and the receiver operating characteristic (ROC) curve was used to analyze the value of DSA-CS and CTP-CS in predicting the clinical outcome. Among 40 patients, 33 (82.5%) acquired recanalization and 16 (40.0%) got good outcome. Compared with poor outcome group, the collateral score (all P collateral vessels were higher in good outcome group (all P collateral vessels were independent factor of good outcome (CTP-CS: OR =48.404, 95% CI :1.373-1706.585, P Collateral scores based on CTP and DSA had good consistency ( κ =0.697, P <0.01), and ROC curve showed that the predictive value of CTP-CS and DSA-CS were comparable (both AUC=0.726, 95% CI :0.559-0.893, P <0.05). CTP-CS can predict the clinical outcome of patients with anterior circulation ischemic stroke after thrombectomy.

32 CFR 536.51 - Collateral source rule.

Science.gov (United States)

2010-07-01

... 32 National Defense 3 2010-07-01 2010-07-01 true Collateral source rule. 536.51 Section 536.51... AGAINST THE UNITED STATES Investigation and Processing of Claims § 536.51 Collateral source rule. Where permitted by applicable state or maritime law, damages recovered from collateral sources are payable under...

10 CFR 1015.210 - Liquidation of collateral.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Liquidation of collateral. 1015.210 Section 1015.210... for the Administrative Collection of Claims § 1015.210 Liquidation of collateral. (a) DOE may liquidate security or collateral through the exercise of a power of sale in the security instrument or a...

Multiple coil closure of isolated aortopulmonary collateral

Directory of Open Access Journals (Sweden)

Padhi Sumanta

2010-01-01

Full Text Available A 7-month-old girl was diagnosed to have large aortopulmonary collateral during evaluation for congestive heart failure. There was no other evidence of cardiopulmonary disease. The collateral was successfully closed with multiple coils delivered sequentially. We describe the issues associated during closure of the aortopulmonary collateral in this case. To the best of our knowledge, this is the first reported case of large aortopulmonary collateral presenting with heart failure in an otherwise structurally normal heart that was closed successfully with multiple coils delivered sequentially.

Imaging findings of pulmonary vascular disorders in portal hypertension

International Nuclear Information System (INIS)

Nagasawa, Kenichi; Takahashi, Koji; Furuse, Makoto

2004-01-01

The purpose of this study was to demonstrate and compare the imaging findings of hepatopulmonary syndrome and portopulmonary hypertension. We retrospectively reviewed the imaging findings of five patients with hepatopulmonary syndrome and four patients with portopulmonary hypertension. We evaluated chest radiographs, chest and abdominal computed tomography (CT) scans, 99m Tc-macroaggregated albumin (MAA) lung perfusion scans, and pulmonary angiograms. In patients with hepatopulmonary syndrome, the presence of peripheral pulmonary vascular dilatation was detected by chest radiograph, chest CT scan, and pulmonary angiogram, especially the basilar segment. 99m Tc-MAA lung perfusion scan showed extrapulmonary tracer distribution (brain, thyroid, and kidney), which revealed pulmonary right-left shunting. In patients with portopulmonary hypertension, chest radiographs and chest CT scans showed the classic findings of primary pulmonary hypertension. In patients with both disorders, extrahepatic features of portal hypertension including ascites, splenomegaly, and portosystemic collateral vessels were seen on abdominal CT. In conclusion, chest radiographs and CT in hepatopulmonary syndrome usually showed peripheral pulmonary vascular dilatation, whereas those in portopulmonary hypertension showed central pulmonary artery dilatation. The extrahepatic features of portal hypertension might be helpful for the diagnosis of both disorders. (author)

27 CFR 17.114 - Release of collateral.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Release of collateral. 17... PRODUCTS Bonds and Consents of Sureties Termination of Bonds § 17.114 Release of collateral. The release of collateral security pledged and deposited to satisfy the bond requirement of this part is governed by the...

26 CFR 403.29 - Deposit of collateral.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Deposit of collateral. 403.29 Section 403.29... ADMINISTRATION DISPOSITION OF SEIZED PERSONAL PROPERTY Seizures and Forfeitures § 403.29 Deposit of collateral... principal by the United States, may be pledged and deposited by claimants as collateral security in lieu of...

27 CFR 72.25 - Deposit of collateral.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Deposit of collateral. 72... Seizures and Forfeitures § 72.25 Deposit of collateral. (a) Bonds or notes of the United States, or other... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in...

Reexamining the Empirical Relation between Loan Risk and Collateral : The Role of the Economic Characteristics of Collateral

OpenAIRE

Berger, A.N.; Frame, W.S.; Ioannidou, V.

2012-01-01

Abstract: This paper offers a possible explanation for the conflicting results in the literature concerning the empirical relation between collateral and loan risk. We posit that certain economic characteristics of collateral may be associated with the empirical dominance of different risk-collateral channels implied by economic theory, namely the “lender selection,” “borrower selection,” “risk-shifting,” and “loss mitigation” channels. Each of these four channels has different predictions re...

The collateral circulation of the heart

Science.gov (United States)

2013-01-01

The coronary arteries have been regarded as end arteries for decades. However, there are functionally relevant anastomotic vessels, known as collateral arteries, which interconnect epicardial coronary arteries. These vessels provide an alternative source of blood supply to the myocardium in cases of occlusive coronary artery disease. The relevance of these collateral arteries is a matter of ongoing debate, but increasing evidence indicates a relevant protective role in patients with coronary artery disease. The collateral circulation can be assessed by different methods; the gold standard involves intracoronary pressure measurements. While the first clinical trials to therapeutically induce growth of collateral arteries have been unavailing, recent pilot studies using external counterpulsation or growth factors such as granulocyte colony stimulating factor (G-CSF) have shown promising results. PMID:23735225

13 CFR 120.343 - Collateral.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Collateral. 120.343 Section 120.343 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Export Working Capital Program (ewcp) § 120.343 Collateral. A Borrower must give SBA a first security...

Collateral in Loan Classification and Provisioning

OpenAIRE

In W Song

2002-01-01

Adequate loan classification practices are an essential part of a sound and effective credit risk-management process in a bank. Failure to identify deterioration in credit quality in a timely manner can aggravate and prolong the problem. Two key issues arise with regard to the use of collateral in the context of loan classification and provisioning. In particular, the questions arise whether collateral should be taken into account in classifying a collateralized loan, and whether it should be...

46 CFR 308.509 - Collateral deposit fund.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Collateral deposit fund. 308.509 Section 308.509... Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a) Requirements. An assured electing to use a cash collateral deposit fund pursuant to § 308.507 shall comply with...

Radionuclide identification algorithm for organic scintillator-based radiation portal monitor

Energy Technology Data Exchange (ETDEWEB)

Paff, Marc Gerrit, E-mail: mpaff@umich.edu; Di Fulvio, Angela; Clarke, Shaun D.; Pozzi, Sara A.

2017-03-21

We have developed an algorithm for on-the-fly radionuclide identification for radiation portal monitors using organic scintillation detectors. The algorithm was demonstrated on experimental data acquired with our pedestrian portal monitor on moving special nuclear material and industrial sources at a purpose-built radiation portal monitor testing facility. The experimental data also included common medical isotopes. The algorithm takes the power spectral density of the cumulative distribution function of the measured pulse height distributions and matches these to reference spectra using a spectral angle mapper. F-score analysis showed that the new algorithm exhibited significant performance improvements over previously implemented radionuclide identification algorithms for organic scintillators. Reliable on-the-fly radionuclide identification would help portal monitor operators more effectively screen out the hundreds of thousands of nuisance alarms they encounter annually due to recent nuclear-medicine patients and cargo containing naturally occurring radioactive material. Portal monitor operators could instead focus on the rare but potentially high impact incidents of nuclear and radiological material smuggling detection for which portal monitors are intended.

Radionuclide identification algorithm for organic scintillator-based radiation portal monitor

Science.gov (United States)

Paff, Marc Gerrit; Di Fulvio, Angela; Clarke, Shaun D.; Pozzi, Sara A.

2017-03-01

We have developed an algorithm for on-the-fly radionuclide identification for radiation portal monitors using organic scintillation detectors. The algorithm was demonstrated on experimental data acquired with our pedestrian portal monitor on moving special nuclear material and industrial sources at a purpose-built radiation portal monitor testing facility. The experimental data also included common medical isotopes. The algorithm takes the power spectral density of the cumulative distribution function of the measured pulse height distributions and matches these to reference spectra using a spectral angle mapper. F-score analysis showed that the new algorithm exhibited significant performance improvements over previously implemented radionuclide identification algorithms for organic scintillators. Reliable on-the-fly radionuclide identification would help portal monitor operators more effectively screen out the hundreds of thousands of nuisance alarms they encounter annually due to recent nuclear-medicine patients and cargo containing naturally occurring radioactive material. Portal monitor operators could instead focus on the rare but potentially high impact incidents of nuclear and radiological material smuggling detection for which portal monitors are intended.

12 CFR 263.17 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding... Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral attack is brought in... shall be excused based on the pendency before any court of any interlocutory appeal or collateral attack. ...

12 CFR 1780.16 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding... Rules § 1780.16 Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral... subpart shall be excused based on the pendency before any court of any interlocutory appeal or collateral...

12 CFR 509.17 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding....17 Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral attack is... shall be excused based on the pendency before any court of any interlocutory appeal or collateral attack. ...

Collateral and its Substitutes in Emerging Markets' Lending

OpenAIRE

Lukas Menkhoff; Doris Neuberger; Ornsiri Rungruxsirivorn

2011-01-01

Due to opaque information and weak enforcement in emerging loan markets, the need for collateral is high, whereas borrowers lack adequate assets to pledge as collateral. How is this puzzle solved? We find for a representative sample from Northeast Thailand that indeed most loans do not include any tangible assets as collateral. Instead, lenders enforce collateral-free loans through third-party guarantees and relationship lending, but also through modifying loan terms, such as reducing loan si...

Lateral collateral ligament of the elbow joint

DEFF Research Database (Denmark)

Olsen, Bo Sanderhoff; Vaesel, M T; Søjbjerg, Jens Ole

1996-01-01

The structure and kinematics of the lateral collateral ligament of the elbow joint were investigated in 10 cadaveric specimens. The lateral collateral ligament was observed to be a distinct part of the lateral collateral ligament complex. It contains posterior fibers that pass through the annular....... Division of the posterolateral capsule caused no further laxity. Cutting the lateral collateral ligament induced a maximum laxity of 11.8 degrees at 110 degrees of flexion in forced varus and a maximum laxity of 20.6 degrees at 110 degrees of flexion in forced external rotation. The corresponding maximal...... posterior radial head translation was observed at 80 degrees to 100 degrees of flexion and was 5.7 mm in forced varus and 8.1 mm in forced external rotation. This study suggests the lateral collateral ligament to be an important stabilizer of the humeroulnar joint and the radial head in forced varus...

Moral hazard in the credit market when the collateral value is stochastic

OpenAIRE

Niinimäki, Juha-Pekka

2010-01-01

This theoretical paper explores the effects of costly and non-costly collateral on moral hazard, when collateral value may fluctuate. Given that all collateral is costly, stochastic collateral will entail the same positive incentive effects as nonstochastic collateral, provided the variation in collateral value is modest. If it is large, the incentive effects are smaller under stochastic collateral. With non-costly collateral, stochastic collateral entails positive incentive effects or no eff...

The human coronary collateral circulation: development and clinical importance.

Science.gov (United States)

Seiler, Christian; Stoller, Michael; Pitt, Bertram; Meier, Pascal

2013-09-01

Coronary collaterals are an alternative source of blood supply to myocardium jeopardized by ischaemia. In comparison with other species, the human coronary collateral circulation is very well developed. Among individuals without coronary artery disease (CAD), there are preformed collateral arteries preventing myocardial ischaemia during a brief vascular occlusion in 20-25%. Determinants of such anastomoses are low heart rate and the absence of systemic arterial hypertension. In patients with CAD, collateral arteries preventing myocardial ischaemia during a brief occlusion are present in every third individual. Collateral flow sufficient to prevent myocardial ischaemia during coronary occlusion amounts to one-fifth to one-fourth the normal flow through the open vessel. Myocardial infarct size, the most important prognostic determinant after such an event, is the product of coronary artery occlusion time, area at risk for infarction, and the inverse of collateral supply. Well-developed coronary collateral arteries in patients with CAD mitigate myocardial infarcts and improve survival. Approximately one-fifth of patients with CAD cannot be revascularized by percutaneous coronary intervention or coronary artery bypass grafting. Therapeutic promotion of collateral growth is a valuable treatment strategy in those patients. It should aim at growth of large conductive collateral arteries (arteriogenesis). Potential arteriogenic approaches include the treatment with granulocyte colony-stimulating factor, physical exercise training, and external counterpulsation.

ASH External Web Portal (External Portal) -

Data.gov (United States)

Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

41 CFR 105-55.014 - Liquidation of collateral.

Science.gov (United States)

2010-07-01

... collateral. 105-55.014 Section 105-55.014 Public Contracts and Property Management Federal Property... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.014 Liquidation of collateral. (a) The General Services Administration (GSA) will liquidate security or collateral through the exercise of a...

48 CFR 48.104-3 - Sharing collateral savings.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Sharing collateral savings... CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a) The Government shares collateral savings with the contractor, unless the head of the contracting activity has...

48 CFR 2448.104-3 - Sharing collateral savings.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Sharing collateral savings... DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of the HCA to determine that the cost of calculating and tracking collateral savings will exceed the...

Collateral circulations in inferior vena cava obstruction

International Nuclear Information System (INIS)

Lee, Jong Beum; Park, Jae Hyung; Han, Man Chung; Park, Soo Soung

1985-01-01

Obstruction of the inferior vena cava (IVC) is an uncommon condition, and the collateral pathway varies according to the level, extent, duration and the cause of obstruction. Membranous obstruction of IVC in its hepatic portion might be one of the principle cause among Korean, though not reported till now. Analytical study was performed in 26 cases of IVC obstruction with various cause. 1. The level of the obstruction showed relatively even distribution as follows, upper caval in 11 cases, middle caval in 6 cases and infrarenal in 9 cases. 2. The main cause of upper caval obstruction was membranous obstruction. 3. As a whole, the main collateral pathway was the central route (22 cases: 85%). 4. Characteristic collateral pathway unique to upper caval obstruction was transhepatic venous collateral, developed between the obstructed segment and unobstructed segment of IVC. 5. Scalloping of left cardiac border produced by pericardiophrenic venous collateral was characteristic simple chest x-ray finding in IVC obstruction

The specialized portals in the knowledge transfer systems: the ionizing radiation portal http://www.ionizantes.ciemat.es/

International Nuclear Information System (INIS)

Arboli, M. Marco; Hernanz, Oscar; Couchoud Gregory, Milagros

2008-01-01

Full text: This paper shows the new infrastructure to disseminate RP knowledge and information developed by the community involved in radiation uses. The www.ionizantes.ciemat.es portal has been implemented by CIEMAT and CINDOC- CSIC with the support of the national and international organizations related to the radiation applications. The design and structure of the databases was developed by CIEMAT and CINDOC-CSIC using the experience acquired by both organizations in the knowledge transfer. The initiative aims to establish collaboration with the sector involved in the most important applications of the ionizing radiation uses. The goal is to share resources establishing a new system of information between the experts, researchers and public. The portal also brings the dialogue to the entire sector and provides details of the relevant research projects. The main specific objectives of this portal are: a) To inform about the new projects developed; b) To download publications, reports and papers; c) to learn more about ionizing radiation; d) To promote collaborative knowledge transfer. The portal shows particular relevance to representative international and national organizations, the private sector and the local community relevant organizations. Results: The resources include in the database of the portal are: the agenda, documents, research calls, legislation, research projects, most important journals and summaries, patents and other available tools. The information is presented in a categorized and classified structure. This virtual community offers better knowledge transfer. It also optimizes the communication and research dissemination to the society. (author)

Portal venous stent placement for treatment of portal hypertension caused by benign main portal vein stenosis.

Science.gov (United States)

Shan, Hong; Xiao, Xiang-Sheng; Huang, Ming-Sheng; Ouyang, Qiang; Jiang, Zai-Bo

2005-06-07

To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. Portal vein stents were implanted in six patients with benign main portal vein stenosis (inflammatory stenosis in three cases, postprocedure of liver transplantation in another three cases). Changes in portal vein pressure, portal vein patency, relative clinical symptoms, complications, and survival were evaluated. Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in six patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3+/-4.7) cm H(2)O to (18.0+/-1.9) cm H(2)O. The portal blood flow restored and the symptoms caused by portal hypertension were eliminated. There were no severe procedure-related complications. The patients were followed up for 1-48 mo. The portal vein remained patent during follow-up. All patients survived except for one patient who died of other complications of liver transplantation. Percutaneous portal vein stent placement for the treatment of portal hypertension caused by benign main portal vein stenosis is safe and effective.

Reexamining the Empirical Relation between Loan Risk and Collateral : The Role of the Economic Characteristics of Collateral

NARCIS (Netherlands)

Berger, A.N.; Frame, W.S.; Ioannidou, V.

2012-01-01

Abstract: This paper offers a possible explanation for the conflicting results in the literature concerning the empirical relation between collateral and loan risk. We posit that certain economic characteristics of collateral may be associated with the empirical dominance of different

Collateral Circulation in Chronic Total Occlusions - An Interventional Perspective

Science.gov (United States)

Choo, Gim-Hooi

2015-01-01

Human coronary collaterals are inter-coronary communications that are believed to be present from birth. In the presence of chronic total occlusions, recruitment of flow via these collateral anastomoses to the arterial segment distal to occlusion provide an alternative source of blood flow to the myocardial segment at risk. This mitigates the ischemic injury. Clinical outcome of coronary occlusion ie. severity of myocardial infarction/ischemia, impairment of cardiac function and possibly survival depends not only on the acuity of the occlusion, extent of jeopardized myocardium, duration of ischemia but also to the adequacy of collateral circulation. Adequacy of collateral circulation can be assessed by various methods. These coronary collateral channels have been used successfully as a retrograde access route for percutaneous recanalization of chronic total occlusions. Factors that promote angiogenesis and further collateral remodeling ie. arteriogenesis have been identified. Promotion of collateral growth as a therapeutic target in patients with no suitable revascularization option is an exciting proposal.

Collateral Circulation in Chronic Total Occlusions - an interventional perspective.

Science.gov (United States)

Choo, Gim-Hooi

2015-09-09

Human coronary collaterals are inter-coronary communications that are believed to be present from birth. In the presence of chronic total occlusions, recruitment of flow via these collateral anastomoses to the arterial segment distal to occlusion provide an alternative source of blood flow to the myocardial segment at risk. This mitigates the ischemic injury. Clinical outcome of coronary occlusion ie. severity of myocardial infarction/ischemia, impairment of cardiac function and possibly survival depends not only on the acuity of the occlusion, extent of jeopardized myocardium, duration of ischemia but also to the adequacy of collateral circulation. Adequacy of collateral circulation can be assessed by various methods. These coronary collateral channels have been used successfully as a retrograde access route for percutaneous recanalization of chronic total occlusions. Factors that promote angiogenesis and further collateral remodeling ie. arteriogenesis have been identified. Promotion of collateral growth as a therapeutic target in patients with no suitable revascularization option is an exciting proposal.

Medial collateral ligament healing one year after a concurrent medial collateral ligament and anterior cruciate ligament injury: an interdisciplinary study in rabbits.

Science.gov (United States)

Yamaji, T; Levine, R E; Woo, S L; Niyibizi, C; Kavalkovich, K W; Weaver-Green, C M

1996-03-01

The optimal treatment for concurrent injuries to the medial collateral and anterior cruciate ligaments has not been determined, despite numerous clinical and laboratory studies. The objective of this study was to examine the effect of surgical repair of the medial collateral ligament on its biomechanical and biochemical properties 52 weeks after such injuries. In the left knee of 12 skeletally mature New Zealand White rabbits, the medial collateral ligament was torn and the anterior cruciate ligament was transected and then reconstructed. This is an experimental model previously developed in our laboratory. In six rabbits, the torn ends of the medial collateral ligament were repaired, and in the remaining six rabbits, the ligament was not repaired. Fifty-two weeks after injury, we examined varus-valgus and anterior-posterior knee stability; structural properties of the femur-medial collateral ligament-tibia complex; and mechanical properties, collagen content, and mature collagen crosslinking of the medial collateral ligament. We could not detect significant differences between repair and nonrepair groups for any biomechanical or biochemical property. Our data support clinical findings that when the medial collateral and anterior cruciate ligaments are injured concurrently and the anterior cruciate ligament is reconstructed, conservative treatment of the ruptured medial collateral ligament can result in successful healing.

24 CFR 1005.107 - What is eligible collateral?

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false What is eligible collateral? 1005... URBAN DEVELOPMENT LOAN GUARANTEES FOR INDIAN HOUSING § 1005.107 What is eligible collateral? (a) In general. A loan guaranteed under section 184 may be secured by any collateral authorized under and not...

Pleiotrophin levels are associated with improved coronary collateral circulation.

Science.gov (United States)

Türker Duyuler, Pinar; Duyuler, Serkan; Gök, Murat; Kundi, Harun; Topçuoğlu, Canan; Güray, Ümit

2018-01-01

Elucidation of the underlying mechanisms of angiogenesis and arteriogenesis in coronary collateral formation is necessary for new therapies. Pleiotrophin is a secreted multifunctional cytokine and associated with the formation of functional cardiovascular neovascularization in a series of experimental animal models. We aimed to evaluate the serum levels of pleiotrophin in patients with chronic total coronary artery occlusion and poor or good collateral development. We included 88 consecutive patients (mean age of the entire population: 63.7±12.1 years, 68 male patients) with stable angina pectoris who underwent coronary angiography and had chronic total occlusion in at least one major coronary artery. Collateral grading was performed according to the Rentrop classification. After grading, patients were divided into poor collateral circulation (Rentrop grade 0 and 1) and good collateral circulation (Rentrop grades 2 and 3) groups. Serum pleiotrophin levels were measured using a commercial human ELISA kit. Fifty-eight patients had good and 30 patients had poor coronary collaterals. The good collateral group had higher serum pleiotrophin levels than the poor collateral group (690.1±187.9 vs. 415.3±165.9 ng/ml, Pcollateral development (odds ratio: 1.007; confidence interval: 1.003-1.012; P=0.002). This study showed that increased serum pleiotrophin levels are associated with better developed coronary collateral circulation. Further studies are needed to better understand the relationship.

45 CFR 160.532 - Collateral estoppel.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Collateral estoppel. 160.532 Section 160.532 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES ADMINISTRATIVE DATA STANDARDS AND RELATED REQUIREMENTS GENERAL ADMINISTRATIVE REQUIREMENTS Procedures for Hearings § 160.532 Collateral estoppel. When a...

Collaterals 2016: Translating the collaterome around the globe.

Science.gov (United States)

Liebeskind, David S; Woolf, Graham W; Shuaib, Ashfaq

2017-06-01

Collaterals 2016 (third International Symposium on Collaterals to the Brain) was a multidisciplinary scientific conference focused on collateral circulation in acute ischemic stroke. Decisive challenges include generalizability of optimal triage and selection paradigms based on collateral status for definitive treatment of acute ischemic stroke, rapid dissemination of expert methods, and the urgent need to leverage networking opportunities for stroke science related to the hemodynamics of collaterals. The collaterome, or individual capacity to offset ischemia in the brain, and determination of a favorable collateral profile have become pivotal factors in consideration of the precision medicine of stroke decision-making. The conference convened over 50 invited faculty from around the world to connect on-site participants at a state-of-the-art facility with remote audiences in more than 22 countries and regions. The 2½-day program was structured into 40-min sessions devoted to key issues in translating the collaterome in acute stroke therapy across the globe. This unique forum of expertise emphasized the timely impact of collaterals on a monumental scale, encouraging maximal participation, rapid diffusion and added value of a diverse networking resource. The meeting format established a model geographical framework and innovative videoconferencing platform for future scientific conferences.

Transmission portal in vivo dosimetry by means of the Monte Carlo method and the mathematical programming language MATLAB

International Nuclear Information System (INIS)

BadraouiCuprova, K.

2014-01-01

Modern radiotherapy has increased demand for dose delivery verification. In this paper transmission portal dosimetry was considered. Portal detectors are a promising tool for 2D dosimetric verification and they are nowadays one of the most widely investigated topics. In this study an Electronic Portal Imaging Device (EPID) was positioned below the patient and the transmission images were captured during the irradiation. The principle of this verification consists of comparison of the acquired images with images predicted on the basis of the entrance fluence map and the tissue distribution in the patient. Such verification is not performed at any radiotherapy department in the Czech Republic. There is no system available for the prediction of transmission portal images. Even worldwide, there is still a lack of commercially available solutions. The aim of this paper is to present a new method of prediction of transmission portal images by means of the Monte Carlo (MC) method and the mathematical programming language MATLAB. The MC code EGSnrc (Electron Gamma Shower) was used. The validity of the presented method was verified by comparison of the predicted images with the acquired ones. The acquisition of EPID images was performed at the Hospital Na Bulovce. Three different validation tests were performed. In the first case, the EPID was irradiated by regular and irregular fields while there was nothing present in the beam path. In the second case, a water-equivalent phantom was added to the EPID and was irradiated by a number of irregular fields. In the third case, a real patient was present in the beam path and the EPID images were acquired during the patient's treatment. The patient was irradiated by 8 treatment fields and the portal images were acquired during 5 treatment fractions. All of the acquired images were compared with the MC predicted ones by gamma analysis with gamma criteria of 3%, 3 mm. The average gamma values were 0.31-0.4, 0.34-0.4 and 0.35-0.61 in

42 CFR 402.15 - Collateral estoppel.

Science.gov (United States)

2010-10-01

... 42 Public Health 2 2010-10-01 2010-10-01 false Collateral estoppel. 402.15 Section 402.15 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS General Provisions § 402.15 Collateral estoppel...

20 CFR 498.114 - Collateral estoppel.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Collateral estoppel. 498.114 Section 498.114 Employees' Benefits SOCIAL SECURITY ADMINISTRATION CIVIL MONETARY PENALTIES, ASSESSMENTS AND RECOMMENDED EXCLUSIONS § 498.114 Collateral estoppel. In a proceeding under section 1129 of the Social Security Act that...

Real-time Cherenkov emission portal imaging during CyberKnife® radiotherapy

International Nuclear Information System (INIS)

Roussakis, Yiannis; Mason, Suzannah; Dehghani, Hamid; Zhang, Rongxiao; Heyes, Geoff; Webster, Gareth; Green, Stuart; Pogue, Brian

2015-01-01

The feasibility of real-time portal imaging during radiation therapy, through the Cherenkov emission (CE) effect is investigated via a medical linear accelerator (CyberKnife ® ) irradiating a partially-filled water tank with a 60 mm circular beam. A graticule of lead/plywood and a number of tissue equivalent materials were alternatively placed at the beam entrance face while the induced CE at the exit face was imaged using a gated electron-multiplying-intensified-charged-coupled device (emICCD) for both stationary and dynamic scenarios. This was replicated on an Elekta Synergy ® linear accelerator with portal images acquired using the iViewGT ™ system. Profiles across the acquired portal images were analysed to reveal the potential resolution and contrast limits of this novel CE based portal imaging technique and compared against the current standard. The CE resolution study revealed that using the lead/plywood graticule, separations down to 3.4  ±  0.5 mm can be resolved. A 28 mm thick tissue-equivalent rod with electron density of 1.69 relative to water demonstrated a CE contrast of 15% through air and 14% through water sections, as compared to a corresponding contrast of 19% and 12% using the iViewGT ™ system. For dynamic scenarios, video rate imaging with 30 frames per second was achieved. It is demonstrated that CE-based portal imaging is feasible to identify both stationary and dynamic objects within a CyberKnife ® radiotherapy treatment field. (note)

Dynamics of the Collateral Encyclopedia

DEFF Research Database (Denmark)

Thellefsen, Torkild Leo; Sørensen, Bent; Thellefsen, Martin Muderspach

2015-01-01

Both Umberto Eco and Charles S. Peirce have been concerned with the notion of background knowledge. Eco refers to background knowledge as the encyclopedia; Peirce’s term of reference is collateral experience. The aim of this article is to investigate the degree to which these two concepts...... are comparable. We focus on one major metaphysical issue, viz. the fact that Eco defines collateral experience, which is the first step in any process of cognition, as private, whereas Peirce, as a realist, would never accept the concept of private thoughts, feelings, etc. We suggest that freeing collateral...... experience from its nominalistic nomenclature makes possible a comparison and synthesis of Eco’s and Peirce’s conceptions when seen from the perspectives of their cognitive type, nuclear type, and molar content....

Coronary collateral vessels in patients with previous myocardial infarction

International Nuclear Information System (INIS)

Nakatsuka, M.; Matsuda, Y.; Ozaki, M.

1987-01-01

To assess the degree of collateral vessels after myocardial infarction, coronary angiograms, left ventriculograms, and exercise thallium-201 myocardial scintigrams of 36 patients with previous myocardial infarction were reviewed. All 36 patients had total occlusion of infarct-related coronary artery and no more than 70% stenosis in other coronary arteries. In 19 of 36 patients with transient reduction of thallium-201 uptake in the infarcted area during exercise (Group A), good collaterals were observed in 10 patients, intermediate collaterals in 7 patients, and poor collaterals in 2 patients. In 17 of 36 patients without transient reduction of thallium-201 uptake in the infarcted area during exercise (Group B), good collaterals were seen in 2 patients, intermediate collaterals in 7 patients, and poor collaterals in 8 patients (p less than 0.025). Left ventricular contractions in the infarcted area were normal or hypokinetic in 10 patients and akinetic or dyskinetic in 9 patients in Group A. In Group B, 1 patient had hypokinetic contraction and 16 patients had akinetic or dyskinetic contraction (p less than 0.005). Thus, patients with transient reduction of thallium-201 uptake in the infarcted area during exercise had well developed collaterals and preserved left ventricular contraction, compared to those in patients without transient reduction of thallium-201 uptake in the infarcted area during exercise. These results suggest that the presence of viable myocardium in the infarcted area might be related to the degree of collateral vessels

42 CFR 3.532 - Collateral estoppel.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Collateral estoppel. 3.532 Section 3.532 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS PATIENT SAFETY ORGANIZATIONS AND PATIENT SAFETY WORK PRODUCT Enforcement Program § 3.532 Collateral estoppel. When a final...

42 CFR 1003.114 - Collateral estoppel.

Science.gov (United States)

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Collateral estoppel. 1003.114 Section 1003.114 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OIG AUTHORITIES CIVIL MONEY PENALTIES, ASSESSMENTS AND EXCLUSIONS § 1003.114 Collateral estoppel. (a) Where a...

Concurrent Hepatic Artery and Portal Vein Thrombosis after Orthotopic Liver Transplantation with Preserved Allografts

Directory of Open Access Journals (Sweden)

Arshad Khan

2014-01-01

Full Text Available In contrast to early HAT, late HAT has an insidious clinical presentation. Nevertheless, biliary and vascular reconstructions in this late setting are unlikely to improve outcome. Patent portal flow makes an important contribution to the viability of liver in case of late HAT while the allograft reconstitutes intrahepatic arterial flow through neovascularization. Concurrent HAT with PVT without immediate graft necrosis is extremely rare, and allograft and patient survival are seemingly impossible without retransplantation. In fact, hepatopetal arterial and portal venous neovascularization are known albeit obscure phenomena that can preserve posttransplant hepatic function under the extenuating circumstances of complete interruption of blood flow to the graft. We describe two such cases that developed combined HAT and PVT more than six months after OLT with perfect preservation of graft function. The survival of allografts in our cases was due to extensive hepatopetal arterial and portal venous collateralization. Simultaneous HAT and PVT after OLT are rare events and almost uniformly fatal, if they occur early. Due to paucity of such cases, however, underlying mechanisms and etiology remain elusive, and despite radiological diagnosis of these complications, there is no way to predict these events in the wake of stable graft function.

Internal Carotid Artery Stenosis and Collateral Recruitment in Stroke Patients.

Science.gov (United States)

Dankbaar, Jan W; Kerckhoffs, Kelly G P; Horsch, Alexander D; van der Schaaf, Irene C; Kappelle, L Jaap; Velthuis, Birgitta K

2017-04-24

Leptomeningeal collaterals improve outcome in stroke patients. There is great individual variability in their extent. Internal carotid artery (ICA) stenosis may lead to more extensive recruitment of leptomeningeal collaterals. The purpose of this study was to evaluate the association of pre-existing ICA stenosis with leptomeningeal collateral filling visualized with computed tomography perfusion (CTP). From a prospective acute ischemic stroke cohort, patients were included with an M1 middle cerebral artery (MCA) occlusion and absent ipsilateral, extracranial ICA occlusion. ICA stenosis was determined on admission CT angiography (CTA). Leptomeningeal collaterals were graded as good (>50%) or poor (≤50%) collateral filling in the affected MCA territory on CTP-derived vessel images of the admission scan. The association between ipsilateral ICA stenosis ≥70% and extent of collateral filling was analyzed using logistic regression. In a multivariable analysis the odds ratio (OR) of ICA stenosis ≥70% was adjusted for complete circle of Willis, gender and age. We included 188 patients in our analyses, 50 (26.6%) patients were classified as having poor collateral filling and 138 (73.4%) as good. Of the patients 4 with poor collateral filling had an ICA stenosis ≥70% and 14 with good collateral filling. Unadjusted and adjusted ORs of ICA stenosis ≥70% for good collateral filling were 1.30 (0.41-4.15) and 2.67 (0.81-8.77), respectively. Patients with poor collateral filling had a significantly worse outcome (90-day modified Rankin scale 3-6; 80% versus 52%, p = 0.001). No association was found between pre-existing ICA stenosis and extent of CTP derived collateral filling in patients with an M1 occlusion.

: acquired resistance in mice by implantation of young irradiated worms into the portal system

Directory of Open Access Journals (Sweden)

Paulo Marcos Z. Coelho

1989-02-01

Full Text Available In two distinct experiments, immature S. mansoni worms (LE strain, Belo Horizonte, Brazil, aged 20 days, obtained from the portal system of white outbred mice, were irradiated with 14 and 4 Krad, respectively. Afterwards, the worms were directly inoculated into the portal vein of normal mice. Inoculation was performed with 20 irradiated worms per animal. Fifty days after inoculation, the mice that received 4 and 14 Krad-irradiated worms and their respective controls were infected with S. mansoni cercariae (LE strain, by transcutaneous route. Twenty days after this challenge infection, the animals were sacrificed and perfused for mature irradiated (90-day-old and immature (20-day-old worm counts. Analysis of the results showed that statistically significant protection against cercariae occurred in both groups with irradiated worms.

Splenophrenic portosystemic shunt in dogs with and without portal ...

African Journals Online (AJOL)

The possible existence of the same pattern of porto-caval connection in dogs having a single congenital portosystemic shunt (CPSS) and in dogs having multiple acquired portosystemic shunt (MAPSS) secondary to portal hypertension (PH) was evaluated. Retrospective evaluation of all CT examinations of patients having ...

Blood pressure and collateral circulation in acute ischemic stroke.

Science.gov (United States)

Wufuer, A; Mijiti, P; Abudusalamu, R; Dengfeng, H; Jian, C; Jianhua, M; Xiaoning, Z

2018-03-20

This study aimed to evaluate the effect of different blood pressure (BP) parameters on the collateral circulation in a retrospective cohort of patients with acute ischemic stroke and ipsilateral internal carotid artery (ICA) occlusion. The degree of intracranial collaterals was graded according to the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) Collateral Flow Grading System. At 12-72 h after stroke onset, six BP measurements were obtained in 124 patients with ICA occlusion. Baseline clinical and imaging characteristics were collected. Group comparisons were performed, and the collateral score (CS) was assessed and entered into a logistic regression analysis. In all, 80 (64.5%) patients displayed good collateral filling (CS ≥ 2). Good intracranial collaterals were more frequently associated with the development of collaterals in the anterior communicating artery, posterior communicating artery, and leptomeningeal artery. The systolic blood pressure (SBP; p = 0.018), diastolic blood pressure (DBP; p = 0.013), and mean arterial pressure (MAP; p = 0.016) were significantly associated with good CS. Median CS was highest when SBP was 120-130 mm Hg (p = 0.034). Logistic regression analysis showed that hypertension (p = 0.026, OR: 0.380, 95% CI: 0.163-0.890) was a significant predictor of poor CS. The development of collateral circulation in patients with acute ischemic stroke with ICA occlusion may be influenced by BP. A moderately decreased SBP is associated with good integrity of the collateral circulation in patients with acute ischemic stroke with occlusion of the ICA.

Oncogenomic portals for the visualization and analysis of genome-wide cancer data.

Science.gov (United States)

Klonowska, Katarzyna; Czubak, Karol; Wojciechowska, Marzena; Handschuh, Luiza; Zmienko, Agnieszka; Figlerowicz, Marek; Dams-Kozlowska, Hanna; Kozlowski, Piotr

2016-01-05

Somatically acquired genomic alterations that drive oncogenic cellular processes are of great scientific and clinical interest. Since the initiation of large-scale cancer genomic projects (e.g., the Cancer Genome Project, The Cancer Genome Atlas, and the International Cancer Genome Consortium cancer genome projects), a number of web-based portals have been created to facilitate access to multidimensional oncogenomic data and assist with the interpretation of the data. The portals provide the visualization of small-size mutations, copy number variations, methylation, and gene/protein expression data that can be correlated with the available clinical, epidemiological, and molecular features. Additionally, the portals enable to analyze the gathered data with the use of various user-friendly statistical tools. Herein, we present a highly illustrated review of seven portals, i.e., Tumorscape, UCSC Cancer Genomics Browser, ICGC Data Portal, COSMIC, cBioPortal, IntOGen, and BioProfiling.de. All of the selected portals are user-friendly and can be exploited by scientists from different cancer-associated fields, including those without bioinformatics background. It is expected that the use of the portals will contribute to a better understanding of cancer molecular etiology and will ultimately accelerate the translation of genomic knowledge into clinical practice.

Transarterial chemoembolization through collateral vessels in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Kim, Ji Hye; Han, Joon Koo; Chung, Jin Wook; Park, Jae Hyung; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1993-11-15

We performed 70 procedures of transarterial chemoembolization (TAE) through extrahepatic collateral vessels (n=27) or parasitic feeders (n=18) in 45 hepatocellular carcinoma patients. The collaterals developed after interruption of the hepatic artery due to repeated TAE (n=17), surgical ligation (n=7)and primary celiac occlusion (n=3). Radiologic findings suggest the existence of parasitic or collateral supply for hepatocellular carcinoma were 1) a focal defect of Lipiodol retention on CT or plain film after TAE via the hepatic artery, 2) dilated and tortuous vessels around the mass on angiography, 3) persistent elevation of the level of serum alpha-fetoprotein or continuous clinical symptoms in spite of sufficient devascularization of the tumor via the hepatic artery, and 4) radiological findings of direct invasion into adjacent organ. The sites of the catheter placement were the inferior phrenic artery(n=19), omental branches(n=16), periportal collaterals (n=6), pancreaticodenal arcade (n=3), gastroduodenal artery(n=3), internal mammary artery (n=2), intercosal artery (n=2), lateral thoracic artery (n=1), bronchial artery (n=1), and colic branches (n=1). Masses feeded by the inferior phrenic and chest wall collaterals were usually located at the dome area of the liver, and the omental and gastroduodenal collaterals developed in the masses located at the inferior tip of the liver. After TAE via collateral vessels, 37 patients underwent follow-up study. In 18 cases(48%), the tumor favorably responded to TAE. Specific complications of collateral TAE were epigastric soreness (n=10), severe shoulder pain (n=4), and embolization of the spinal artery during embolization through the intercostal artery (n=1). In conclusion, various extrahepatic collateals are important alternative or addition routes for effective chemoembolization in patients with advanced hepatoma, and early recognition of the parasitic supply and the effort to perform TAE via collaterals is very

Transarterial chemoembolization through collateral vessels in hepatocellular carcinoma

International Nuclear Information System (INIS)

Kim, Ji Hye; Han, Joon Koo; Chung, Jin Wook; Park, Jae Hyung; Han, Man Chung

1993-01-01

We performed 70 procedures of transarterial chemoembolization (TAE) through extrahepatic collateral vessels (n=27) or parasitic feeders (n=18) in 45 hepatocellular carcinoma patients. The collaterals developed after interruption of the hepatic artery due to repeated TAE (n=17), surgical ligation (n=7)and primary celiac occlusion (n=3). Radiologic findings suggest the existence of parasitic or collateral supply for hepatocellular carcinoma were 1) a focal defect of Lipiodol retention on CT or plain film after TAE via the hepatic artery, 2) dilated and tortuous vessels around the mass on angiography, 3) persistent elevation of the level of serum alpha-fetoprotein or continuous clinical symptoms in spite of sufficient devascularization of the tumor via the hepatic artery, and 4) radiological findings of direct invasion into adjacent organ. The sites of the catheter placement were the inferior phrenic artery(n=19), omental branches(n=16), periportal collaterals (n=6), pancreaticodenal arcade (n=3), gastroduodenal artery(n=3), internal mammary artery (n=2), intercosal artery (n=2), lateral thoracic artery (n=1), bronchial artery (n=1), and colic branches (n=1). Masses feeded by the inferior phrenic and chest wall collaterals were usually located at the dome area of the liver, and the omental and gastroduodenal collaterals developed in the masses located at the inferior tip of the liver. After TAE via collateral vessels, 37 patients underwent follow-up study. In 18 cases(48%), the tumor favorably responded to TAE. Specific complications of collateral TAE were epigastric soreness (n=10), severe shoulder pain (n=4), and embolization of the spinal artery during embolization through the intercostal artery (n=1). In conclusion, various extrahepatic collateals are important alternative or addition routes for effective chemoembolization in patients with advanced hepatoma, and early recognition of the parasitic supply and the effort to perform TAE via collaterals is very

Zinc release from Schaffer collaterals and its significance.

Science.gov (United States)

Takeda, Atsushi; Nakajima, Satoko; Fuke, Sayuri; Sakurada, Naomi; Minami, Akira; Oku, Naoto

2006-02-15

On the basis of the evidence that approximately 45% of Schaffer collateral boutons are zinc-positive, zinc release from Schaffer collaterals and its action were examined in hippocampal slices. When zinc release from Schaffer collaterals was examined using ZnAF-2, a membrane-impermeable zinc indicator, ZnAF-2 signal in the stratum radiatum of the CA1 was increased by tetanic stimuli at 100 Hz for 1s, suggesting that zinc is released from Schaffer collaterals in a calcium- and impulse-dependent manner. An in vivo microdialysis experiment indicated that the perfusion with 10 microM zinc significantly decreases extracellular glutamate concentration in the CA1. When tetanic stimuli at 100 Hz for 5s were delivered to the dentate granule cells, the increase in calcium signal in the stratum radiatum of the CA1, as well as in the stratum lucidum of the CA3, was attenuated by addition of 10 microM zinc, while enhanced by addition of 1mM CaEDTA, a membrane-impermeable zinc chelator. The increase in calcium signal in the CA1, in which Schaffer collateral synapses exist, during delivery of tetanic stimuli at 100 Hz for 1s to the Schaffer collateral-commissural pathway was also significantly enhanced by addition of 1mM CaEDTA. These results suggest that zinc released from Schaffer collaterals suppressively modulates presynaptic and postsynaptic calcium signaling in the CA1, followed by the suppression of glutamate release.

Coronary collateral circulation during exercise assessed with stress Tl-201 SPECT

International Nuclear Information System (INIS)

Tanaka, Takeshi; Aizawa, Tadanori

1995-01-01

Stree Tl-201 single photon emission computed tomography (SPECT) was undertaken in 25 patients with complete occlusion of the left anterior descending artery in which the major collateral circulation was septal segment supplied by the right posterior descending artery with no significant occlusion. The ratio of blood flow in ischemic area to that in normal area was quantitatively determined on Tl-201 images, and the degree of ischemia was expressed by Tl uptake ratio. Ischemia was found in 22 of the 25 patients. Of the 22 patients, 9 showed Tl uptake ratio of less than 50%. Tl uptake ratio in the inferior segment was 76.8±10.3%. In 11 patients, it was less than 75%. Redistribution images were acquired in 19 patients. Changes in Tl uptake ratio on the 90 degrees projection of the septum were less than 20%, with a lowest value of 59.1±11.3% in 14 patients; and these were 20% or more, with a lowest value of 45.2±11.1% in 8 patients. When coronary collateral circulation is not supplied by exercise, septal perfusion may be decreased. In cases of complete occlusion of the anteiror descending artery, ischemia may not uniform over the whole ischemic area and may be noticeable around the anterior descending artery. In cases of lesions in the anteior descending artery, however, collateral circulation supplied by the right coronary artery may occur by exercise when ischemia in the anterior segment was severer than in the septal segment. (N.K.)

12 CFR 308.17 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding... PRACTICE RULES OF PRACTICE AND PROCEDURE Uniform Rules of Practice and Procedure § 308.17 Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral attack is brought in any...

12 CFR 19.17 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding... OF PRACTICE AND PROCEDURE Uniform Rules of Practice and Procedure § 19.17 Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral attack is brought in any court concerning all...

Radiologic analysis of the medical collateral ligament rupture

International Nuclear Information System (INIS)

Cho, Chung Che; Lee, Chang Jun; Kim, Kun Sang; Park, Soo Soung

1979-01-01

The medical collateral ligament rupture is the most common injury involving the knee joint ligaments. The ruptured medical collateral ligaments of 73 cases with clinical and surgical confirmations were radiologically analyzed. The results were obtained as follows: 1. The most risky age for tearing of the medical collateral ligament was third to fifth decades (50 cases of male and 23 of females). 2. The most common cause of the medical collateral ligament rupture was traffic accident (82.2%). 3. The mean distance of medial knee joint space was 7.9 ± 2.0 mm on the normal side and 13.7 ± 4.2 mm on the affected side. 4. The mean degree of knee joint space was 10.1 ± 2.5 on the normal side and 14.7 ± 3.8 on the affected side. 5. The fibula was the bone fractured most frequently in association with the medial collateral ligament rupture (30.6%).

Diagnosis of hepatic encephalopathy with magentic resonance imaging

International Nuclear Information System (INIS)

Inoue, Etsuo; Narumi, Yoshifumi; Kadota, Tsuyoshi; Fujita, Makoto; Kuriyama, Keiko; Kuroda, Chikazumi

1993-01-01

Cranial magnetic resonance (MR) images were examined in 16 patients with liver cirrhosis. The findings of MR imaging were correlated with portal-systemic collateral vessel shown on angiograms. In 9 of 16 patients, basal ganglia was hyperintense compared with white matter on T1-weighted images. These 9 patients had portal-systemic collateral vessel 10 mm or more in diameter that was suppied by superior mesenteric vein (SMV), and 4 of the 9 patients had portal-systemic encephalopathy on angiograms. In the remaining 7 patients, no hyperintense lesions were seen in basal ganglia relative to white matter on T1-weighted images; angiography revealed that 2 patients had portal-systemic collateral vessel that was supplied by SMV but was 5 mm or less in diameter, 3 had bood supplies from splenic vein, and 2 had no collateral vessel. There was no change in signal intensity on T2-weighted images. In conclusion, a large portal-systemic collateral vessel supplied by SMV may be shown as a high intensity lesion in basal ganglia, thus making it possible to diagnose hepatic encephalopathy even if there was no psychoneurologic symptoms or signs. (N.K.)

Toxic shock syndrome due to community-acquired methicillin-resistant Staphylococcus aureus infection: Two case reports and a literature review in Japan.

Science.gov (United States)

Sada, Ryuichi; Fukuda, Saori; Ishimaru, Hiroyasu

2017-01-01

Community-acquired methicillin-resistant Staphylococcus aureus has been spreading worldwide, including in Japan. However, few cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus have been reported in Japan. We report 2 cases, in middle-aged women, of toxic shock syndrome due to Community-acquired methicillin-resistant Staphylococcus aureus via a vaginal portal of entry. The first patient had used a tampon and the second patient had vaginitis due to a cleft narrowing associated with vulvar lichen sclerosus. Both patients were admitted to our hospital with septic shock and severe acute kidney injury and subsequently recovered with appropriate antibiotic treatment. In our review of the literature, 8 cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus were reported in Japan. In these 8 cases, the main portals of entry were the skin and respiratory tract; however, the portal of entry of Community-acquired methicillin-resistant Staphylococcus aureus from a vaginal lesion has not been reported in Japan previously.

12 CFR 747.17 - Collateral attacks on adjudicatory proceeding.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding... INVESTIGATIONS Uniform Rules of Practice and Procedure § 747.17 Collateral attacks on adjudicatory proceeding. If an interlocutory appeal or collateral attack is brought in any court concerning all or any part of an...

Masculinity discourse on media text: A critical review about news about violence on online news portals

Directory of Open Access Journals (Sweden)

Daniel Susilo

2017-12-01

Full Text Available Media as a medium plays a significant role in strengthening gender concept in society. Female’s sexualities are viewed as an object of judgement for the media. For the sake of men readers’ satisfaction, media justifies itself in its attempts to exploit women sexuality. Masculine’s way of thinking has been perpetuated in reports about women. Masculine men are considered empowering female’s bodies. Violence acts are considered as the form of masculine domination over feminine beings. This research aims to dismantle how media construct their texts on masculine discourses on online news portals. Online news portals are required to be swift in uploading news and using their acquired resources; thus, they perpetuate this masculine discourse. Critical discourse analysis of Van Dick was employed to unravel masculine discourse structures on media texts at the largest news portals in Indonesia, Alexa.com; and Tribunnews.com; which belong to a corporate media, Kompas Gramedia. The findings of this research state that online news portals and their acquired resources strengthen violence labelling as a part of masculine domination over feminine beings.

Evaluation of the Knowledge Management Mechanisms of Brazilian Northeast Universities Hospital Portals

Directory of Open Access Journals (Sweden)

Helio Roberto Hekis

2013-12-01

Full Text Available Hospital portals that manage health related data are becoming increasingly popular since they play an important role to provide, acquire and exchange information to its users. This study aims to verify how the hospital portals are contributing to the expansion of users knowledge by the analysis of interactive features associated with three mechanisms of knowledge management: Knowledge Access (KA; Knowledge Creation (KC; and Knowledge Transfer (KT. The study is exploratory, descriptive and qualitative, classified as a survey, and involves the standardization of data collection instruments (questionnaires and interviews applied directly to people of a particular population to evaluate the knowledge management the portals present on the university hospitals from northeastern of Brazil. The results indicated that the proceeds of access to knowledge (AK prevailed over other confirming the results found on the Asians and Americans hospital portals. 

Documenting and automating collateral evolutions in Linux device drivers

DEFF Research Database (Denmark)

Padioleau, Yoann; Hansen, René Rydhof; Lawall, Julia

2008-01-01

. Manually performing such collateral evolutions is time-consuming and unreliable, and has lead to errors when modifications have not been done consistently. In this paper, we present an automatic program transformation tool, Coccinelle, for documenting and automating device driver collateral evolutions...... programmer. We have evaluated our approach on 62 representative collateral evolutions that were previously performed manually in Linux 2.5 and 2.6. On a test suite of over 5800 relevant driver files, the semantic patches for these collateral evolutions update over 93% of the files completely...

Portal Vein Thrombosis

Directory of Open Access Journals (Sweden)

Hakan Demirci

2016-01-01

Full Text Available Portal vein thrombosis is an important cause of presinusoidal portal hypertension. Portal vein thrombosis commonly occurs in patient with cirrhosis, malignancy and prothrombotic states. Patients with acute portal vein thrombosis have immediate onset. Patients with chronic portal vein thrombosis have developed portal hypertension and cavernous portal transformation. Portal vein thrombosis is diagnosed with doppler ultrasound, computed tomography and magnetic resonance imaging. Therapy with low molecular weight heparin achieves recanalization in more than half of acute cases.

Noninvasive assessment of coronary collaterals in man by PET perfusion imaging

International Nuclear Information System (INIS)

Demer, L.L.; Gould, K.L.; Goldstein, R.A.; Kirkeeide, R.L.

1990-01-01

At present, coronary collateralization cannot be identified or assessed noninvasively in patients. In animal studies, coronary collaterals are associated with coronary steal, defined as a regional fall in perfusion during coronary arteriolar vasodilation. To determine the effect of coronary arteriolar vasodilation on collateral bed perfusion in man, myocardial perfusion imaging was performed before and after pharmacologic coronary vasodilation in patients with coronary artery disease (CAD). Regional myocardial activity of 82 Rb or 13 N ammonia was measured by positron emission tomography (PET) at rest and with intravenous dipyridamole/handgrip stress in 28 patients with angiographic collaterals and in 25 control patients with similar CAD severity by quantitative arteriography. Regional myocardial activity decreased after dipyridamole, indicating coronary steal, in 25 of 28 patients with angiographic collaterals and in only 4 of 25 control patients without angiographic collaterals. These findings suggest that developed collaterals are associated with myocardial steal in patients with CAD, allowing potential use of PET for non-invasive identification of coronary collateralization

Collateral Function in Patients with Coronary Occlusion Evaluated by 201Thallium Scintigraphy

Directory of Open Access Journals (Sweden)

Aida Hasanović

2008-11-01

Full Text Available The present study evaluated the impact of the angiographically documented collaterals on regional myocardial perfusion measured by 201thallium scintigraphy in patients with a chronic total occlusion.The study included 60 patients with chronic total occlusion who underwent rest-stress myocardial perfusion scintigraphy and coronary angiography. All patients had angiographic evidence of coronary collaterals. Patients were divided into two groups: group one had well-developed coronary collateral vessels (n=35 and group II had poor coronary collateral development (n=25.Patients with chronic total occlusion had severe and extensive stress-induced myocardial perfusion defects regardless of the grade of angiographic coronary collaterals. The perfusion defects in the group with good collaterals were predominantly reversible, suggesting that coronary collaterals preserved myocardial viability in the regions subtended by a total coronary occlusion. A significant correlation between good collaterals with complete protection and poor collaterals with no protection was noted.Our results demonstrate a protective effect of collaterals on myocardial perfusion during coronary occlusion. The effective angiographic collaterals may prevent resting regional wall motion abnormalities but do not appear to protect against stress-induced perfusion defect.

Screening in the credit market when the collateral value is stochastic

OpenAIRE

Niinimäki, Juha-Pekka

2009-01-01

This theoretical paper explores screening with loan collateral when both the collateral value and the probability of project success fluctuate. Some model versions challenge the classic findings of Bester (1985) by showing that high-risk borrowers may in such case be more willing to pledge collateral than low-risk borrowers. Abundant collateral then would not signal low risk. The results may help explain the mixed empirical findings on the role of collateral. The paper also extends the analys...

Collateral Intimate Partner Homicide

Directory of Open Access Journals (Sweden)

Emily Meyer

2013-04-01

Full Text Available Collateral intimate partner homicide (CIPH is an underinvestigated genre of intimate partner violence (IPV where an individual(s connected to the IPV victim is murdered. We conducted a content analysis of a statewide database of CIPH newspaper articles (1990-2007. Out of 111 collateral murder victims, there were 84 IPV female focal victims and 84 male perpetrators. The most frequently reported CIPH decedent was the focal victim’s new partner (30%; 45% of focal victims were themselves killed. News reports framed CIPH as the unexpected result of interpersonal conflict, despite evidence of a systematic pattern of coercion and violence that capitulated in murder.

Detection of human collateral circulation by vasodilation-thallium-201 tomography

International Nuclear Information System (INIS)

Nienaber, C.A.; Salge, D.; Spielmann, R.P.; Montz, R.; Bleifeld, W.

1990-01-01

Coronary arteriolar vasodilation may provoke redistribution of flow to collateral-dependent jeopardized myocardium. To assess the physiologic significance of collaterals, 80 consecutive post-infarction patients (age 58 +/- 8 years) underwent vasodilation-redistribution thallium-201 tomographic imaging after administration of 0.56 mg of intravenous dipyridamole/kg body weight. Circumferential profile analysis of thallium-201 uptake and redistribution in representative left ventricular tomograms provided quantitative assessment of transient and fixed defects and separation between periinfarctional and distant inducible hypoperfusion. Tomographic perfusion data were correlated to wall motion and collateral circulation between distinct anatomic perfusion territories. Patients were grouped according to presence (59%) or absence (41%) of angiographically visible collateral channels to jeopardized myocardium. In the presence of collaterals, distant reversible defects were larger than in absence of collaterals (p less than 0.05); the extent of combined periinfarctional and distant redistribution was also larger in collateralized patients (p less than 0.025), whereas the size of the persistent perfusion defect was similar in both groups. By prospective analysis the tomographic perfusion pattern of combined periinfarctional and distant redistribution revealed a sensitivity of 85% and a specificity of 78% for the detection of significant collateral circulation in this group of patients. Thus, using the exhausted flow reserve as a diagnostic tool, vasodilation-thallium-201 tomography has the potential to identify and quantitate collateralized myocardium in post-infarction patients and may guide diagnostic and therapeutic decision-making

Effect of nitroglycerin on myocardial collateral conductance in awake dogs

International Nuclear Information System (INIS)

Brazzamano, S.; Rembert, J.C.; Greenfield, J.C. Jr.

1988-01-01

Conductance of the coronary collateral circulation during the course of two abrupt circumflex coronary occlusions was measured in awake dogs ∼ 2 wk after collateral vessels were stimulated to develop. The pressure gradient from the central aorta to the distal circumflex coronary artery was measured, and myocardial blood flow was determined by 9-μm radioactive microspheres at 30 s and 4 min after coronary occlusions. Collateral conductance was calculated as mean collateral blood flow divided by the mean aorta-coronary pressure gradient. Before nitroglycerin, collateral conductance increased in all eight dogs from 30 s to 4 min. After nitroglycerin administration, the conductance at 30 s increased from the prenitroglycerin control value to 0.014 ± 0.012 ml·min -1 ·g -1 ·mmHg -1 . The mean change in conductance from 30 s to 4 min postnitroglycerin was significantly less than during prenitroglycerin. These data indicate that an increase in conductance during coronary occlusion occurs even in the immature collateral circulation. This effect presumably takes place in the arterial smooth muscle at the origin of the collateral vasculature

13 CFR 120.1850 - Will the Collateral be held by SBA?

Science.gov (United States)

2010-01-01

... Loan Program) § 120.1850 Will the Collateral be held by SBA? Yes, SBA or its expressly authorized agent... all Collateral for SISMBD Loans in a custodial account. Certificates held as Collateral must be in... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Will the Collateral be held by SBA...

Obliterative portal venopathy without portal hypertension: an underestimated condition.

Science.gov (United States)

Guido, Maria; Sarcognato, Samantha; Sonzogni, Aurelio; Lucà, Maria Grazia; Senzolo, Marco; Fagiuoli, Stefano; Ferrarese, Alberto; Pizzi, Marco; Giacomelli, Luciano; Colloredo, Guido

2016-03-01

Obliterative portal venopathy without portal hypertension has been described by a single study in a limited number of patients, thus very little is known about this clinical condition. This study aimed to investigate the prevalence of obliterative portal venopathy and its clinical-pathological correlations in patients with cryptogenic chronic liver test abnormalities without clinical signs of portal hypertension. We analysed 482 liver biopsies from adults with non-cirrhotic cryptogenic chronic liver disorders and without any clinical signs of portal hypertension, consecutively enrolled in a 5-year period. Twenty cases of idiopathic non-cirrhotic portal hypertension diagnosed in the same period, were included for comparison. Histological findings were matched with clinical and laboratory features. Obliterative portal venopathy was identified in 94 (19.5%) of 482 subjects and in all 20 cases of idiopathic non-cirrhotic portal hypertension: both groups shared the entire spectrum of histological changes described in the latter condition. The prevalence of incomplete fibrous septa and nodular regenerative hyperplasia was higher in the biopsies of idiopathic non-cirrhotic portal hypertension (P = 0.006 and P = 0.002), a possible hint of a more advanced stage of the disease. The two groups also shared several clinical laboratory features, including a similar liver function test profile, concomitant prothrombotic conditions and extrahepatic autoimmune disorders. Obliterative portal venopathy occurs in a substantial proportion of patients with unexplained chronic abnormal liver function tests without portal hypertension. The clinical-pathological profile of these subjects suggests that they may be in an early (non-symptomatic) stage of idiopathic non-cirrhotic portal hypertension. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Coronary Collateral Growth—Back to the Future

Science.gov (United States)

Chilian, William M.; Penn, Marc S.; Pung, Yuh Fen; Dong, Feng; Mayorga, Maritza; Ohanyan, Vahagn; Logan, Suzanna; Yin, Liya

2012-01-01

The coronary collateral circulation is critically important as an adaptation of the heart to prevent the damage from ischemic insults. In their native state, collaterals in the heart would be classified as part of the microcirculation, existing as arterial-arterial anastomotic connections in the range of 30 to 100 μM in diameter. However, these vessels also show a propensity to remodel into components of the macrocirculation and can become arteries larger than a 1000 μM in diameter. This process of outward remodelling is critically important in the adaptation of the heart to ischemia because the resistance to blood flow is inversely related to the fourth power of the diameter of the vessel. Thus, an expansion of a vessel from 100 to 1000 μM would reduce resistance (in this part of the circuit) to a negligible amount and enable delivery of flow to the region at risk. Our goal in this review is to highlight the voids in understanding this adaptation to ischemia—the growth of the coronary collateral circulation. In doing so we discuss the controversies and unknown aspects of the causal factors that stimulate growth of the collateral circulation, the role of genetics, and the role of endogenous stem and progenitor cells in the context of the normal, physiological situation and under more pathological conditions of ischemic heart disease or with some of the underlying risk factors, e.g., diabetes. The major conclusion of this review is that there are many gaps in our knowledge of coronary collateral growth and this knowledge is critical before the potential of stimulating collateralization in the hearts of patients can be realized. PMID:22210280

10 CFR 609.15 - Default, demand, payment, and collateral liquidation.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Default, demand, payment, and collateral liquidation. 609... PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.15 Default, demand, payment, and collateral liquidation... Guaranteed Obligation. Such assignment shall include all related liens, security, and collateral rights to...

Status of systemic to pulmonary arterial collateral flow after the fontan procedure.

Science.gov (United States)

Whitehead, Kevin K; Harris, Matthew A; Glatz, Andrew C; Gillespie, Matthew J; DiMaria, Michael V; Harrison, Neil E; Dori, Yoav; Keller, Marc S; Rome, Jonathan J; Fogel, Mark A

2015-06-15

The investigators recently validated a method of quantifying systemic-to-pulmonary arterial collateral flow using phase-contrast magnetic resonance imaging velocity mapping. Cross-sectional data suggest decreased collateral flow in patients with total cavopulmonary connections (TCPCs) compared with those with superior cavopulmonary connections (SCPCs). However, no studies have examined serial changes in collateral flow from SCPCs to TCPCs in the same patients. The aim of this study was to examine differences in collateral flow between patients with SCPCs and those with TCPCs. Collateral flow was quantified by 2 independent measures from 250 single-ventricle studies in 219 different patients (115 SCPC and 135 TCPC studies, 31 patients with both) and 18 controls, during routine studies using through-plane phase-contrast magnetic resonance imaging. Collateral flow was indexed to body surface area, aortic flow, and pulmonary venous flow. Regardless of indexing method, SCPC patients had significantly higher collateral flow than TCPC patients (1.64 ± 0.8 vs 1.03 ± 0.8 L/min/m(2), p <0.001). In 31 patients who underwent serial examinations, collateral flow as a fraction of aortic flow increased early after TCPC completion. In TCPC patients, indexed collateral flow demonstrated a significant negative correlation with time from TCPC. In conclusion, SCPC and TCPC patients demonstrate substantial collateral flow, with SCPC patients having higher collateral flow than TCPC patients overall. On the basis of the paired subset analysis, collateral flow does not decrease in the short term after TCPC completion and trends toward an increase. In the long term, however, collateral flow decreases over time after TCPC completion. Copyright © 2015 Elsevier Inc. All rights reserved.

The cumulative verification image analysis tool for offline evaluation of portal images

International Nuclear Information System (INIS)

Wong, John; Yan Di; Michalski, Jeff; Graham, Mary; Halverson, Karen; Harms, William; Purdy, James

1995-01-01

Purpose: Daily portal images acquired using electronic portal imaging devices contain important information about the setup variation of the individual patient. The data can be used to evaluate the treatment and to derive correction for the individual patient. The large volume of images also require software tools for efficient analysis. This article describes the approach of cumulative verification image analysis (CVIA) specifically designed as an offline tool to extract quantitative information from daily portal images. Methods and Materials: The user interface, image and graphics display, and algorithms of the CVIA tool have been implemented in ANSCI C using the X Window graphics standards. The tool consists of three major components: (a) definition of treatment geometry and anatomical information; (b) registration of portal images with a reference image to determine setup variation; and (c) quantitative analysis of all setup variation measurements. The CVIA tool is not automated. User interaction is required and preferred. Successful alignment of anatomies on portal images at present remains mostly dependent on clinical judgment. Predefined templates of block shapes and anatomies are used for image registration to enhance efficiency, taking advantage of the fact that much of the tool's operation is repeated in the analysis of daily portal images. Results: The CVIA tool is portable and has been implemented on workstations with different operating systems. Analysis of 20 sequential daily portal images can be completed in less than 1 h. The temporal information is used to characterize setup variation in terms of its systematic, random and time-dependent components. The cumulative information is used to derive block overlap isofrequency distributions (BOIDs), which quantify the effective coverage of the prescribed treatment area throughout the course of treatment. Finally, a set of software utilities is available to facilitate feedback of the information for

7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Warehouse-stored marketing assistance loan collateral... Marketing Assistance Loans § 1421.106 Warehouse-stored marketing assistance loan collateral. (a) A commodity may be pledged as collateral for a warehouse-stored marketing assistance loan in the quantity...

12 CFR 614.4250 - Collateral evaluation standards.

Science.gov (United States)

2010-01-01

..., personal, or intangible property is taken as security for a loan or is the subject of a lease, an evaluation of such property shall be performed in accordance with § 614.4260 and the institutions' policies and procedures. Such a collateral evaluation shall be identified as either a collateral valuation or a...

Radioisotopic flow scanning for portal blood flow and portal hypertension

International Nuclear Information System (INIS)

Hesdorffer, C.S.; Bezwoda, W.R.; Danilewitz, M.D.; Esser, J.D.; Tobias, M.

1987-01-01

The use of a simple, noninvasive, isotope scanning technique for the determination of relative portal blood flow and detection of portal hypertension is described. Using this technique the presence of portal hypertension was demonstrated in seven of nine patients known to have elevated portal venous pressure. By contrast, esophageal varices were demonstrated in only five of these patients, illustrating the potential value of the method. Furthermore, this technique has been adapted to the study of portal blood flow in patients with myeloproliferative disorders with splenomegaly but without disturbances in hepatic architecture. Results demonstrate that the high relative splenic flow resulting from the presence of splenomegaly may in turn be associated with elevated relative portal blood flow and portal hypertension. The theoretic reasons for the development of flow-related portal hypertension and its relationship to splenic blood flow are discussed

Patient portal readiness among postpartum patients in a safety net setting.

Science.gov (United States)

Wieland, Daryl; Gibeau, Anne; Dewey, Caitlin; Roshto, Melanie; Frankel, Hilary

2017-07-05

Maternity patients interact with the healthcare system over an approximately ten-month interval, requiring multiple visits, acquiring pregnancy-specific education, and sharing health information among providers. Many features of a web-based patient portal could help pregnant women manage their interactions with the healthcare system; however, it is unclear whether pregnant women in safety-net settings have the resources, skills or interest required for portal adoption. In this study of postpartum patients in a safety net hospital, we aimed to: (1) determine if patients have the technical resources and skills to access a portal, (2) gain insight into their interest in health information, and (3) identify the perceived utility of portal features and potential barriers to adoption. We developed a structured questionnaire to collect demographics from postpartum patients and measure use of technology and the internet, self-reported literacy, interest in health information, awareness of portal functions, and perceived barriers to use. The questionnaire was administered in person to women in an inpatient setting. Of the 100 participants surveyed, 95% reported routine internet use and 56% used it to search for health information. Most participants had never heard of a patient portal, yet 92% believed that the portal functions were important. The two most appealing functions were to check results and manage appointments. Most participants in this study have the required resources such as a device and familiarity with the internet to access a patient portal including an interest in interacting with a healthcare institution via electronic means. Pregnancy is a critical episode of care where active engagement with the healthcare system can influence outcomes. Healthcare systems and portal developers should consider ways to tailor a portal to address the specific health needs of a maternity population including those in a safety net setting.

Recurrent recessive mutation in deoxyguanosine kinase causes idiopathic noncirrhotic portal hypertension.

Science.gov (United States)

Vilarinho, Sílvia; Sari, Sinan; Yilmaz, Güldal; Stiegler, Amy L; Boggon, Titus J; Jain, Dhanpat; Akyol, Gulen; Dalgic, Buket; Günel, Murat; Lifton, Richard P

2016-06-01

Despite advances in the diagnosis and management of idiopathic noncirrhotic portal hypertension, its pathogenesis remains elusive. Insight may be gained from study of early-onset familial idiopathic noncirrhotic portal hypertension, in which Mendelian mutations may account for disease. We performed exome sequencing of eight subjects from six kindreds with onset of portal hypertension of indeterminate etiology during infancy or childhood. Three subjects from two consanguineous families shared the identical rare homozygous p.N46S mutation in DGUOK, a deoxyguanosine kinase required for mitochondrial DNA replication; haplotype sharing demonstrated that the mutation in the two families was inherited from a remote common ancestor. All three affected subjects had stable portal hypertension with noncirrhotic liver disease for 6-16 years of follow-up. This mutation impairs adenosine triphosphate binding and reduces catalytic activity. Loss-of-function mutations in DGUOK have previously been implicated in cirrhosis and liver failure but not in isolated portal hypertension. Interestingly, treatment of patients with human immunodeficiency viral infection with the nucleoside analogue didanosine is known to cause portal hypertension in a subset of patients and lowers deoxyguanosine kinase levels in vitro; the current findings implicate these effects on deoxyguanosine kinase in the causal mechanism. Our findings provide new insight into the mechanisms mediating inherited and acquired noncirrhotic portal hypertension, expand the phenotypic spectrum of DGUOK deficiency, and provide a new genetic test for a specific cause of idiopathic noncirrhotic portal hypertension. (Hepatology 2016;63:1977-1986). © 2016 by the American Association for the Study of Liver Diseases.

7 CFR 1980.444 - Appraisal of property serving as collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Appraisal of property serving as collateral. 1980.444... Program § 1980.444 Appraisal of property serving as collateral. (a) Appraisal reports prepared by independent qualified fee appraisers will be required on all property that will serve as collateral. In the...

12 CFR 615.5090 - Reduction in carrying value of collateral.

Science.gov (United States)

2010-01-01

... FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Collateral § 615.5090 Reduction in carrying value of collateral. When the bank or Farm Credit Administration determines that a loan did not... withdrawn from collateral until the cause of ineligibility is remedied. When a loan has been classified as a...

Exercise promotes collateral artery growth mediated by monocytic nitric oxide.

Science.gov (United States)

Schirmer, Stephan H; Millenaar, Dominic N; Werner, Christian; Schuh, Lisa; Degen, Achim; Bettink, Stephanie I; Lipp, Peter; van Rooijen, Nico; Meyer, Tim; Böhm, Michael; Laufs, Ulrich

2015-08-01

Collateral artery growth (arteriogenesis) is an important adaptive response to hampered arterial perfusion. It is unknown whether preventive physical exercise before limb ischemia can improve arteriogenesis and modulate mononuclear cell function. This study aimed at investigating the effects of endurance exercise before arterial occlusion on MNC function and collateral artery growth. After 3 weeks of voluntary treadmill exercise, ligation of the right femoral artery was performed in mice. Hindlimb perfusion immediately after surgery did not differ from sedentary mice. However, previous exercise improved perfusion restoration ≤7 days after femoral artery ligation, also when exercise was stopped at ligation. This was accompanied by an accumulation of peri-collateral macrophages and increased expression of endothelial nitric oxide synthase and inducible nitric oxide synthase (iNOS) in hindlimb collateral and in MNC of blood and spleen. Systemic monocyte and macrophage depletion by liposomal clodronate but not splenectomy attenuated exercise-induced perfusion restoration, collateral artery growth, peri-collateral macrophage accumulation, and upregulation of iNOS. iNOS-deficient mice did not show exercise-induced perfusion restoration. Transplantation of bone marrow-derived MNC from iNOS-deficient mice into wild-type animals inhibited exercise-induced collateral artery growth. In contrast to sedentary controls, thrice weekly aerobic exercise training for 6 months in humans increased peripheral blood MNC iNOS expression. Circulating mononuclear cell-derived inducible nitric oxide is an important mediator of exercise-induced collateral artery growth. © 2015 American Heart Association, Inc.

CT imaging of collaterals in stenoses of large mediastinal veins

International Nuclear Information System (INIS)

Goerich, J.; Flentje, M.; Gueckel, F.; Beyer-Enke, S.A.; Kaick, G. van; Heidelberg Univ.

1988-01-01

Scans of angio-computed tomography (CT) of 53 patients suffering from mediastinal space-occupying growths were reviewed: 16 patients showed stenosis of mediastinal veins with demonstration of subcutaneous venous channels, 17 showed an obstruction without collateral pathways and 20 patients had normal mediastinal vessels. Two thirds of the cases with external vein compression were caused by bronchogenic carcinoma. The degree of obstruction in patients showing collateral circulation was between 70 and 100 percent and significantly greater than in patients without collaterals (40%). The most important collaterals bypassing the upper mediastinal veins are discussed. (orig.) [de

Collateral vessels in moyamoya disease : comparison of MR and MRA with conventional angiography

International Nuclear Information System (INIS)

Shim, Joo Eun; Yoon, Dae Young; Yi, Jeong Geun; Kim, Ho Chul; Choi, Chul Sun; Bae, Sang Hoon

1998-01-01

To determine the value of magnetic resonance imaging (MR) and magnetic resonance angiography (MRA) in assessing collateral vessels of moyamoya disease. Twenty-four patients with moyamoya disease who underwent MR, 3D TOF MRA, and conventional angiography participated in this study. Two radiologists working independently and with no knowledge of the angiographic findings, interpreted the MR and MRA images. To determine the presence of parenchymal and leptomeningeal collaterals (48 hemispheres) and transdural collaterals (38 hemispheres in 19 patients were depicted by angiography of the external carotid), the findings were compared with those of angiography. Parenchymal, leptomeningeal, and transdural collaterals were depicted by conventional angiography in 34 (71%), 32 (67%), and 11 (29%) hemispheres respectively. The sensitivity and specificity of MR/MRA for collateral vessels were 79.1/88.1 % for parenchymal collaterals, 72.1/88.1 % for leptomeningeal collaterals, and 0.1/18.1 % for transdural collaterals, respectively. Respective sensitivity and specificity of MR/MRA were 88.94/94.1% for leptomeningeal collaterals, and 18.93/55.1 % for transdural collaterals, when the prominent posterior cerebral and external carotid artery were regarded as secondary signs of leptomeningeal and transdural collateral vessels. In moyamoya disease, MR and MRA are useful imaging modalities for the assessment of collateral vessels. The prominent posterior cerebral artery and external carotid artery can be useful secondary signs of leptomeningeal and transdural collateral vessels. (author). 18 refs., 2 figs

Portal Hypertension

Science.gov (United States)

... Overview of Gallbladder Cancer Additional Content Medical News Portal Hypertension By Steven K. Herrine, MD, Professor of Medicine, ... Liver Hepatic Encephalopathy Jaundice in Adults Liver Failure Portal Hypertension Portal hypertension is abnormally high blood pressure in ...

10 CFR 611.111 - Default, demand, payment, and collateral liquidation.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Default, demand, payment, and collateral liquidation. 611... collateral liquidation. (a) In the event that the Borrower has defaulted in the making of required payments.... Attorney General, may seek to foreclose on the collateral assets and/or take such other legal action as...

Atraumatic medial collateral ligament oedema in medial compartment knee osteoarthritis

International Nuclear Information System (INIS)

Bergin, D.; Keogh, C.; O'Connell, M.; Zoga, A.; Rowe, D.; Shah, B.; Eustace, S.

2002-01-01

Objective: To describe and determine the prevalence of atraumatic medial collateral oedema identified in patients with medial compartment osteoarthritis. Design and patients: Sixty patients, 30 patients with medial compartment knee osteoarthritis (Kellgren and Lawrence grade 2 to 4) and 30 age-matched patients with atraumatic knee pain without osteoarthritis, referred for MR imaging over a 2 year period were included in the study. In each case, severity of osteoarthritis was recorded on radiographs and correlated with the presence or absence of medial collateral ligament oedema at MR imaging. Results: Medial collateral oedema was identified in 27 of the 30 patients with osteoarthritis, of whom 14 had grade 1 oedema and 13 had grade 2 oedema compared with the presence of medial collateral ligament oedema (grade 1) in only two of the 30 control patients without osteoarthritis (P<<0.0001). Conclusion: Medial collateral oedema is common in patients with osteoarthritis in the absence of trauma. When identified, medial collateral ligament oedema should be considered to be a feature of osteoarthritis and should not be incorrectly attributed to an acute traumatic injury. (orig.)

Measuring the quality of eligible collateral

OpenAIRE

Lehmbecker, Philipp; Missong, Martin

2008-01-01

Recently, the U. S. subprime crisis has shown that a weak collateralization of credits may have massive economic implications, entailing severe perturbations of the international financial system. We focus on central bank lending and try to pin down the quantitative impact of the collateralization of central banks' credits. A questionnaire on national monetary frameworks was used to collect data from central banks. Drawing on these data we derive an index of the quality of eligible assets mea...

48 CFR 32.304-6 - Other collateral security.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Other collateral security. 32.304-6 Section 32.304-6 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... collateral security. The following are examples of other forms of security that, although seldom invoked...

Collateral circulation alters downstream hemodynamic stress caused by intracranial atherosclerotic stenosis.

Science.gov (United States)

Liu, Xin; Dornbos, David; Pu, Yuehua; Leng, Xinyi; Song, Ligang; Jia, Baixue; Pan, Yuesong; Wang, David; Miao, Zhongrong; Wang, Yilong; Liu, Liping; Wang, Yongjun

2017-06-01

Fractional flow reserve (FFR) accurately predicts the degree of stenosis and is now widely used to identify clinically significant severe coronary artery lesions. In the current study, we utilized a similar indicator, fractional flow (FF), to determine the hemodynamic impact of symptomatic intracranial atherosclerotic stenosis (ICAS) and to assess the correlation of FF with the severity of stenosis and collateral circulation. Patients with symptomatic ICAS (70-99% stenosis) confirmed on digital subtraction angiography (DSA) were consecutively recruited. FF was obtained during DSA examination with the use of pressure sensors and was measured as a ratio, comparing measurements distal to an ICAS lesion (Pd) and within the aorta (Pa). The degree of leptomeningeal collateralization was graded from zero (absent) to four (complete compensatory). The correlation between FF, anatomical stenosis, and collateral status was then analyzed. Twenty-five patients with a mean age of 55.6 years were analyzed. The median percentage of stenosis and median FF were 82.3 and 0.68%, respectively. Eleven patients were found to have poor collateralization (grade 0-2), and fourteen patients were identified with good collateral circulation (grade 3-4). Overall, the hemodynamic impact of an atherosclerotic lesions worsened (decreased FF) as the percentage of stenosis increased, although this did not reach statistical significance (r = -0.398, p = 0.06). However, the status of collateralization significantly altered this correlation, worsening the hemodynamic impact in patients with poor collateral circulation (r = -0.677, p = 0.032). There was no difference in patients with good collateral circulation (r = -0.279, p = 0.356). An anatomically severe (70-99%) symptomatic ICAS lesion may generate significant hemodynamic stress downstream as assessed by the indicator FF, particularly in patients with poor collateral circulation. Further, good collateralization may mitigate this

Association between neutrophil/lymphocyte ratio and coronary collateral circulation

Directory of Open Access Journals (Sweden)

Mustafa Oylumlu

2012-03-01

Full Text Available Objectives: To investigate relation between neutrophil/lymphocyte ratio and coronary collateral flow.Material and methods: Eighty-two patients admittedDicle University Medical Faculty Hospital Cardiology Departmentwith diagnosis of coronary artery disease anddetected significant stenosis or occlusion at least one ofthe coronary arteries, were included to study. Age, sex,presence of diabetes mellitus and hypertension, acute/stable coronary disease, body mass index, neutrophil/lymphocyte ratio, white blood count, Rentrop scores andnumber of diseased vessel were recorded.Results: Well-developed coronary collateral circulationwas found in 33 of the patients. Forty-nine patients hadpoor coronary collateral circulation. Mean age, sex, bodymass index, presence of diabetes mellitus and hypertensionwere similar in two groups. Mean neutrophil/lymphocyteratio was lower in well-developed coronary collateralcirculation group than poor coronary collateral circulationgroup, but there was no significant differences (2.78 vs2.89, p=0.12.Conclusions: There was no association between neutron/hil lymphocyte ratio and coronary collateral circulationaccording to our data. J Clin Exp Invest 2012; 3(1:29-32

[Synopsis about the hypothesis of "information channel" of channel-collateral system].

Science.gov (United States)

Chang, Xi-Lang

2008-10-01

The author of the present paper founded a theorem about the "incompleteness of single channel structure" (nerve, blood vessel, lymphatic, interspace, aperture, etc.) through quantitative and qualitative analysis about the economic information channel in the human body, which eliminates the probability of single channel structure in the information channel of channel (meridian)-collateral system. After comprehensive analysis on the current researches, the author puts forward a neodoxy, i.e., the body "information channel" structure of the channel-collateral system, mainly follows the distribution regularity of systemic statistics, and is not a single specific entity; various layers of the information channel in the main stems of the channel-collaterals are composed of optimized structure tissues. Hence, the structure of this information channel of channel-collateral system is an overall-optimized, sequential and compatible systemic structure. From this neodoxy, the author brings forward a working principle of channel-collaterals, which is supported theoretically by bio-auxology. The longitudinal distribution of the main stems of meridian-collaterals is considered to result from that in the process of the animal evolution, in the animals moving forward, the microscopic complicated movement of intracorporeal information and energy molecules is related to the forward macroscopic and non-uniform movement of organism in trans-measure. Its impulse and kinetic momentum forms a main vector in the longitudinal direction of the body (the direction of the main stem of channel-collaterals). In order to adapt to and utilize natural regularities, the main stems of the channel-collaterals gradually differentiate and evolve in the living organism, forming a whole system. The "hypothesis of biological origin of channel-collateral system" and "that of information channel of the channel-collaterals in the body" constitute a relatively complete theoretical system framework.

Collateral and debt maturity choice: A signaling model

NARCIS (Netherlands)

Lensink, B.W.; Pham, 27735

2005-01-01

This paper derives optimal loan policies under asymmetric information where banks offer loan contracts of long and short duration, backed or unbacked with collateral. The main novelty of the paper is that it analyzes a setting in which high quality firms use collateral as a complementary device

Negative modulation of presynaptic activity by zinc released from Schaffer collaterals.

Science.gov (United States)

Takeda, Atsushi; Fuke, Sayuri; Tsutsumi, Wataru; Oku, Naoto

2007-12-01

The role of zinc in excitation of Schaffer collateral-CA1 pyramidal cell synapses is poorly understood. Schaffer collaterals stained with ZnAF-2 or ZnAF-2DA, a membrane-impermeable or a membrane-permeable zinc indicator, respectively, were treated by tetanic stimulation (200 Hz, 1 sec). Extracellular and intracellular ZnAF-2 signals were increased in the stratum radiatum of the CA1, in which Schaffer collateral synapses exist. Both the increases were completely blocked in the presence of 1 mM CaEDAT, a membrane-impermeable zinc chelator, suggesting that 1 mM CaEDTA is effective for chelating zinc released from Schaffer collaterals. The role of Schaffer collateral zinc in presynaptic activity was examined by using FM4-64, a fluorescent indicator for vesicular exocytosis. The decrease in FM4-64 signal during tetanic stimulation (10 Hz, 180 sec) was enhanced in Schaffer collaterals in the presence of 1 mM CaEDTA but suppressed in the presence of 5 microM ZnC1(2), suggesting that zinc released from Schaffer collaterals suppresses presynaptic activity during tetanic stimulation. When Schaffer collateral synapses stained with calcium orange AM, a membrane-permeable calcium indicator, were regionally stimulated with 1 mM glutamate, calcium orange signal was increased in the CA1 pyramidal cell layer. This increase was enhanced in the presence of CaEDTA and attenuated in the presence of zinc. These results suggest that zinc attenuates excitation of Schaffer collateral synapses elicited with glutamate via suppression of presynaptic activity. (c) 2007 Wiley-Liss, Inc.

Pure and diluted contrast medium in the evaluation of portal venous system with digital subtraction angiography

International Nuclear Information System (INIS)

Gattoni, F.; Baldini, V.; Pozzato, C.; Nessi, R.; Raiteri, R.; Uscenghi, C.; Opocher, E.; Santambrogio, R.

1990-01-01

We report the results of intra-arterial digital subtraction angiography (DSA) in 100 patients with portal hypertension. The portal venous system was evaluated; all patients underwent angiography of the celiac and superior mesenteric arteries before surgery. Forty-four of them were also examined after Warren splenorenal shunts. Therefore, a total of 144 exams was evaluated. The authors always employed low-osmolality ionic and non-ionic contrast media (iodine concentration: 300-350 mg/ml). In 70 cases pure contrast medium was injected (20/25 ml): in the extant 74 cases it was diluted with an equal volume of saline solution (osmolality and iodine concentration reduced by 50%). Intra-arterial DSA always visualized portal venous system, collateral circulation, shunt location and postoperative changes. The mayor advantage of intra-arterial DSA is the smaller amount of contrast medium injected, so that local and systemic side effects are rare. According to our experience, it is best to dilute the contrast medium and inject the same amount as in conventional angiography, at the same rate. Other well-known advantages of intra-arterial DSA are quicker execution, less injury to arteries using smaller caliber catheters, and low cost. The major disadvantage of intra-arterial DSA, as it appeared also in our study, is the field size of the intensifier, which in our case was limited to 6-9 inches. This is an insufficient coverage for the whole portal system to be studied, and some contrast medium injections become therefore necessary. An average of 3 injections were given to each patient. This problem reduces the advantage of less contrast medium per injection. At any rate, even though intra-arterial DSA exhibits this limitation, it can nevertheless yield important information in the pre- and postoperative evaluation of patients with portal hypertension

Idiopathic portal hypertension

International Nuclear Information System (INIS)

Han, Tae Kyun; Ryu, Dae Sik; Kim, Heung Chul; Hur, Hun; Eom, Kyeung Tae; Namkung, Sook; Park, Man Soo; Hwang, Woo Chul; Lee, Kwan Seop

1996-01-01

To describe the radiologic findings of idiopathic portal hypertension and to find the points of differentiation between idiopathic portal hypertension and liver cirrhosis. Four portograms in five patients who for four years had suffered from pathologically confirmed idiopathic portal hypertension were retrospectively analyzed and compared with a portogram obtained from a control subject with liver cirrhosis. Portographic finding s of idiopathic portal hypertension were paucity of medium-sized portal branches, irregular and obtuse-angled division of peripheral branches, abrupt interruption and an avascular area beneath the liver margin. A portogram of idiopathic portal hypertension may be useful in differentiation this and liver cirrhosis

[Mesenteric-cava shunt's results with autologous jugular vein graft in children with pre-sinusoidal portal hypertension].

Science.gov (United States)

Leal, N; López Santamaría, M; Gámez, M; Murcia, J; Andolfi, G; Berrocal, T; Frauca, E; Jara, P; Tovar, J

2002-07-01

Presinusoidal portal hypertension (PPH) in children evaluates without functional hepatic damage, and with the time, trends to compensate through the creation of spontaneous portosystemic shunts. Nevertheless, some patients suffer episodes of gastrointestinal bleeding (GIB) that because of its frequency or severity, force to propose the change of surgical treatment. To evaluate the results of the mesocaval shunt (MCS) with autologous jugular vein in children with PPH. Among the 32 children with PPH treated in our Hospital in the last 7 years, 10 had episodes of GIB that forced to perform a surgical shunt. The types of shunt were distal splenorenal in 3 patients and mesocaval in 7. These 7 cases are the material of this study. The origin of the PPH was a cavernomatosis transformation of the portal vein in 6 cases and a congenital hepatic fibrosis in 1. Before the surgery the average number of episodes of GIB was 9 (range 2-15); all the patients needed transfusion of blood products and variceal sclerosis. In 2 cases a tamponade with the Sengtaken balloon was required and 5 patients were treated with somatostatin and propranolol. The Doppler ultrasounds revealed and intense hepatofugal collateral circulation in all the cases. The initial flow through the shunt was adequate in all the patients except one who required a percutaneous balloon dilatation. Only this patient has suffered an episode of GIB. The hyperesplenism signs disappeared or improved in all the seven cases and the collateral circulation was significantly reduced. The pressure in the splenic territory decreased around 50% in the 4 patients that was measured. There were no cases of encephalopasty and only one child with congenital hepatic fibrosis shows signs of mild hepatic disfunction. The medium follow up post-shunt is 32 months (range 8 m-6 years). The MCS prevents the GIB in the PPH not responsive to the conservative treatment; its effectiveness is related with an adequate permeability though the graft

Leptomeningeal collateral status predicts outcome after middle cerebral artery occlusion.

Science.gov (United States)

Madelung, C F; Ovesen, C; Trampedach, C; Christensen, A; Havsteen, I; Hansen, C K; Christensen, H

2018-01-01

Perfusion through leptomeningeal collateral vessels is a likely pivotal factor in the outcome of stroke patients. We aimed to investigate the effect of collateral status on outcome in a cohort of unselected, consecutive stroke patients with middle cerebral artery occlusion undergoing reperfusion therapy. This retrospectively planned analysis was passed on prospectively collected data from 187 consecutive patients with middle cerebral artery occlusion admitted within 4.5 hours to one center and treated with intravenous thrombolysis alone (N = 126), mechanical thrombectomy alone (N = 5), or both (N = 56) from May 2009 to April 2014. Non-contrast CT (NCCT) and computed tomography angiography (CTA) were provided on admission and NCCT repeated at 24 hours. Collateral status was assessed based on the initial CTA. Hemorrhagic transformation was evaluated on the 24-hour NCCT and according to European Cooperative Acute Stroke Study (ECASS) criteria. Modified Rankin Scale score was assessed at 90 days, and mortality at 1 year. At 90 days, median (IQR) modified Rankin Scale score in patients with poor collateral status was 4 (3-6) compared to 2 (1-4) in patients with good collateral status (P collateral status were less likely to achieve a good 90-day outcome (modified Rankin Scale score 0-2) (Adjusted odds ratio 0.27, 95% CI: 0.09-0.86). During the first year, 40.9% of patients with poor collateral status died vs 18.2% of the remaining population (P = .001). Leptomeningeal collateral status predicts functional outcome, mortality, and hemorrhagic transformation following middle cerebral artery occlusion. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Coronary collateralization shows sex and racial-ethnic differences in obstructive artery disease patients.

Directory of Open Access Journals (Sweden)

Zhi Liu

Full Text Available Coronary collateral circulation protects cardiac tissues from myocardial infarction damage and decreases sudden cardiac death. So far, it is unclear how coronary collateralization varies by race-ethnicity groups and by sex.We assessed 868 patients with obstructive CAD. Patients were assessed for collateral grades based on Rentrop grading system, as well as other covariates. DNA samples were genotyped using the Affymetrix 6.0 genotyping array. To evaluate genetic contributions to collaterals, we performed admixture mapping using logistic regression with estimated local and global ancestry.Overall, 53% of participants had collaterals. We found difference between sex and racial-ethnic groups. Men had higher rates of collaterals than women (P-value = 0.000175. White Hispanics/Latinos showed overall higher rates of collaterals than African Americans and non-Hispanic Whites (59%, 50% and 48%, respectively, P-value = 0.017, and especially higher rates in grade 1 and grade 3 collateralization than the other two populations (P-value = 0.0257. Admixture mapping showed Native American ancestry was associated with the presence of collaterals at a region on chromosome 17 (chr17:35,243,142-41,251,931, β = 0.55, P-value = 0.000127. African ancestry also showed association with collaterals at a different region on chromosome 17 (chr17: 32,266,966-34,463,323, β = 0.38, P-value = 0.00072.In our study, collateralization showed sex and racial-ethnic differences in obstructive CAD patients. We identified two regions on chromosome 17 that were likely to harbor genetic variations that influenced collateralization.

Electronic portal imaging devices

International Nuclear Information System (INIS)

Lief, Eugene

2008-01-01

The topics discussed include, among others, the following: Role of portal imaging; Port films vs. EPID; Image guidance: Elekta volume view; Delivery verification; Automation tasks of portal imaging; Types of portal imaging (Fluorescent screen, mirror, and CCD camera-based imaging; Liquid ion chamber imaging; Amorpho-silicon portal imagers; Fluoroscopic portal imaging; Kodak CR reader; and Other types of portal imaging devices); QA of EPID; and Portal dosimetry (P.A.)

Acute development of collateral circulation and therapeutic prospects in ischemic stroke

Directory of Open Access Journals (Sweden)

Eri Iwasawa

2016-01-01

Full Text Available In acute ischemic stroke, collateral circulation plays an important role in maintaining blood flow to the tissue that is at risk of progressing into ischemia, and in increasing the successful recanalization rate without hemorrhagic transformation. We have reported that well-developed collateral circulation is associated with smaller infarct volume and better long-term neurological outcome, and it disappears promptly once the effective recanalization is achieved. Contrary to the belief that collateral vessels develop over time in chronic stenotic condition, there exists a phenomenon that collateral circulation develops immediately in acute stenosis or occlusion of the arteries and it seems to be triggered by fluid shear stress, which occurs between the territories of stenotic/occluded arteries and those fed by surrounding intact arteries. We believe that this acute development of collateral circulation is a target of novel therapeutics in ischemic stroke and refer our recent attempt in enhancing collateral circulation by modulating sphingosine-1-phosphate receptor 1, which is a known shear-stress mechanosensing protein.

Acute development of collateral circulation and therapeutic prospects in ischemic stroke.

Science.gov (United States)

Iwasawa, Eri; Ichijo, Masahiko; Ishibashi, Satoru; Yokota, Takanori

2016-03-01

In acute ischemic stroke, collateral circulation plays an important role in maintaining blood flow to the tissue that is at risk of progressing into ischemia, and in increasing the successful recanalization rate without hemorrhagic transformation. We have reported that well-developed collateral circulation is associated with smaller infarct volume and better long-term neurological outcome, and it disappears promptly once the effective recanalization is achieved. Contrary to the belief that collateral vessels develop over time in chronic stenotic condition, there exists a phenomenon that collateral circulation develops immediately in acute stenosis or occlusion of the arteries and it seems to be triggered by fluid shear stress, which occurs between the territories of stenotic/occluded arteries and those fed by surrounding intact arteries. We believe that this acute development of collateral circulation is a target of novel therapeutics in ischemic stroke and refer our recent attempt in enhancing collateral circulation by modulating sphingosine-1-phosphate receptor 1, which is a known shear-stress mechanosensing protein.

Acute development of collateral circulation and therapeutic prospects in ischemic stroke

Institute of Scientific and Technical Information of China (English)

Eri Iwasawa; Masahiko Ichijo; Satoru Ishibashi; Takanori Yokota

2016-01-01

In acute ischemic stroke, collateral circulation plays an important role in maintaining blood lfow to the tissue that is at risk of progressing into ischemia, and in increasing the successful recanalization rate with-out hemorrhagic transformation. We have reported that well-developed collateral circulation is associated with smaller infarct volume and better long-term neurological outcome, and it disappears promptly once the effective recanalization is achieved. Contrary to the belief that collateral vessels develop over time in chronic stenotic condition, there exists a phenomenon that collateral circulation develops immediately in acute stenosis or occlusion of the arteries and it seems to be triggered by lfuid shear stress, which occurs be-tween the territories of stenotic/occluded arteries and those fed by surrounding intact arteries. We believe that this acute development of collateral circulation is a target of novel therapeutics in ischemic stroke and refer our recent attempt in enhancing collateral circulation by modulating sphingosine-1-phosphate recep-tor 1, which is a known shear-stress mechanosensing protein.

The utility of collateral student drinking reports: Evidence from a biomarker study.

Science.gov (United States)

Fendrich, Michael; Fuhrmann, Daniel; Berger, Lisa; Plate, Charles; Lewis, Douglas; Jones, Joseph

2015-11-01

Researchers have increasingly used collateral informants to validate the reports provided by primary research subjects. We assessed the utility of collateral informants for college students in a study that incorporates biomarkers to validate student reports of recent drinking behavior. Students from a Midwestern university were randomly selected for a study in which they provided 90-day Timeline Followback data, hair and fingernail specimens for ethylglucuronide (EtG) testing, and information about collateral (friends or peers) informants who were familiar with their drinking behavior. We compared summary measures of recent drinking to collateral informant reports for the subset of 72 students who were selected to participate in the collateral validation process who had complete measures. Kappa, weighted kappa, and McNemar tests were performed to evaluate levels of agreement. We compared levels of use indicated by each informant within the context of EtG findings. We also compared respondent and collateral reports with respect to heavy drinking directly to EtG test results. There was considerable overlap between the reports provided by the student participants and their collateral informants. Within the context of EtG-informed analyses, collaterals rarely provided new information about heavy use beyond that provided by the study subjects. Collateral informants have limited utility in non-clinical studies of heavy drinking in randomly selected college students. Copyright © 2015. Published by Elsevier Ltd.

27 CFR 25.105 - Release of collateral security.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Release of collateral security. 25.105 Section 25.105 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE... of Bonds Or Consents of Surety § 25.105 Release of collateral security. Bonds, notes, and other...

12 CFR 615.5335 - Bank net collateral ratio.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Bank net collateral ratio. 615.5335 Section 615.5335 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Surplus and Collateral Requirements § 615.5335 Bank net...

10 CFR 609.16 - Perfection of liens and preservation of collateral.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 609.16... THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.16 Perfection of liens and preservation of collateral. (a... to perfect and maintain liens, as applicable, on assets which are pledged as collateral for the...

10 CFR 611.108 - Perfection of liens and preservation of collateral.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 611... of collateral. (a) The Agreement and other documents related thereto shall provide that: (1) DOE and... necessary to perfect and maintain liens, as applicable, on assets which are pledged as collateral for the...

Collateral veins in inferior caval vein occlusion demonstrated via CT

International Nuclear Information System (INIS)

Lien, H.H.; Lund, G.

1983-01-01

CT-scans of 12 patients with tumour-induced occlusion of the inferior vena cava were studied with regard to collateral veins. A comparison was performed with findings at phlebography in 10 patients and at autopsy in 2. The site and appearance of the main collateral pathway are presented. A close study of vascular structures renders useful information on collateral circulation in occlusion of the inferior vena cava. (orig.)

The cerebral collateral circulation: Relevance to pathophysiology and treatment of stroke.

Science.gov (United States)

Ginsberg, Myron D

2017-08-09

The brain's collateral circulation consists of arterial anastomotic channels capable of providing nutrient perfusion to brain regions whose normal sources of flow have become compromised, as occurs in acute ischemic stroke. Modern CT-based neuroimaging is capable of providing detailed information as to collateral extent and sufficiency and is complemented by magnetic resonance-based methods. In the present era of standard-of-care IV thrombolysis for acute ischemic stroke, and following the recent therapeutic successes of randomized clinical trials of acute endovascular intervention, the sufficiency of the collateral circulation has been convincingly established as a key factor influencing the likelihood of successful reperfusion and favorable clinical outcome. This article reviews the features of the brain's collateral circulation; methods for its evaluation in the acute clinical setting; the relevance of collateral circulation to prognosis in acute ischemic stroke; the specific insights into the collateral circulation learned from recent trials of endovascular intervention; and the major influence of genetic factors. Finally, we emphasize the need to develop therapeutic approaches to augment collateral perfusion as an adjunctive strategy to be employed along with, or prior to, thrombolysis and endovascular interventions, and we highlight the possible potential of inhaled nitric oxide, albumin, and other approaches. Copyright © 2017 Elsevier Ltd. All rights reserved.

29 CFR 785.24 - Principles noted in Portal-to-Portal Bulletin.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Principles noted in Portal-to-Portal Bulletin. 785.24 Section 785.24 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR... of Principles Preparatory and Concluding Activities § 785.24 Principles noted in Portal-to-Portal...

Collateral pathways in lumbar epidural venography

International Nuclear Information System (INIS)

Thijssen, H.O.M.; Ike, B.W.; Chevrot, A.; Bijlsma, R.

1982-01-01

Opacification of collateral pathways other than the central channels is very rare in lumbar epidural venography. Two cases of opacification of the inferior mesenteric vein following extravasation of contrast medium at the tip of the lateral sacral vein catheter are reported. One case is presented in which filling of normal parametrial venous plexuses and the left ovarian vein occurred as a consequence of incompetent or absent valves in the internal iliac vein. The literature containing comparable collateral flow patterns in disease is reviewed. The significance of the phlebographic features in our cases is discussed. (orig.)

Leptomeningeal collateral status predicts outcome after middle cerebral artery occlusion

DEFF Research Database (Denmark)

Madelung, Christopher Fugl; Ovesen, C; Trampedach, C

2017-01-01

NCCT and according to European Cooperative Acute Stroke Study (ECASS) criteria. Modified Rankin Scale score was assessed at 90 days, and mortality at 1 year. RESULTS: At 90 days, median (IQR) modified Rankin Scale score in patients with poor collateral status was 4 (3-6) compared to 2 (1-4) in patients...... population (P = .001). CONCLUSIONS: Leptomeningeal collateral status predicts functional outcome, mortality, and hemorrhagic transformation following middle cerebral artery occlusion.......OBJECTIVES: Perfusion through leptomeningeal collateral vessels is a likely pivotal factor in the outcome of stroke patients. We aimed to investigate the effect of collateral status on outcome in a cohort of unselected, consecutive stroke patients with middle cerebral artery occlusion undergoing...

Focal spot motion of linear accelerators and its effect on portal image analysis

International Nuclear Information System (INIS)

Sonke, Jan-Jakob; Brand, Bob; Herk, Marcel van

2003-01-01

The focal spot of a linear accelerator is often considered to have a fully stable position. In practice, however, the beam control loop of a linear accelerator needs to stabilize after the beam is turned on. As a result, some motion of the focal spot might occur during the start-up phase of irradiation. When acquiring portal images, this motion will affect the projected position of anatomy and field edges, especially when low exposures are used. In this paper, the motion of the focal spot and the effect of this motion on portal image analysis are quantified. A slightly tilted narrow slit phantom was placed at the isocenter of several linear accelerators and images were acquired (3.5 frames per second) by means of an amorphous silicon flat panel imager positioned ∼0.7 m below the isocenter. The motion of the focal spot was determined by converting the tilted slit images to subpixel accurate line spread functions. The error in portal image analysis due to focal spot motion was estimated by a subtraction of the relative displacement of the projected slit from the relative displacement of the field edges. It was found that the motion of the focal spot depends on the control system and design of the accelerator. The shift of the focal spot at the start of irradiation ranges between 0.05-0.7 mm in the gun-target (GT) direction. In the left-right (AB) direction the shift is generally smaller. The resulting error in portal image analysis due to focal spot motion ranges between 0.05-1.1 mm for a dose corresponding to two monitor units (MUs). For 20 MUs, the effect of the focal spot motion reduces to 0.01-0.3 mm. The error in portal image analysis due to focal spot motion can be reduced by reducing the applied dose rate

Alternative Evolutionary Paths to Bacterial Antibiotic Resistance Cause Distinct Collateral Effects.

Science.gov (United States)

Barbosa, Camilo; Trebosc, Vincent; Kemmer, Christian; Rosenstiel, Philip; Beardmore, Robert; Schulenburg, Hinrich; Jansen, Gunther

2017-09-01

When bacteria evolve resistance against a particular antibiotic, they may simultaneously gain increased sensitivity against a second one. Such collateral sensitivity may be exploited to develop novel, sustainable antibiotic treatment strategies aimed at containing the current, dramatic spread of drug resistance. To date, the presence and molecular basis of collateral sensitivity has only been studied in few bacterial species and is unknown for opportunistic human pathogens such as Pseudomonas aeruginosa. In the present study, we assessed patterns of collateral effects by experimentally evolving 160 independent populations of P. aeruginosa to high levels of resistance against eight commonly used antibiotics. The bacteria evolved resistance rapidly and expressed both collateral sensitivity and cross-resistance. The pattern of such collateral effects differed to those previously reported for other bacterial species, suggesting interspecific differences in the underlying evolutionary trade-offs. Intriguingly, we also identified contrasting patterns of collateral sensitivity and cross-resistance among the replicate populations adapted to the same drug. Whole-genome sequencing of 81 independently evolved populations revealed distinct evolutionary paths of resistance to the selective drug, which determined whether bacteria became cross-resistant or collaterally sensitive towards others. Based on genomic and functional genetic analysis, we demonstrate that collateral sensitivity can result from resistance mutations in regulatory genes such as nalC or mexZ, which mediate aminoglycoside sensitivity in β-lactam-adapted populations, or the two-component regulatory system gene pmrB, which enhances penicillin sensitivity in gentamicin-resistant populations. Our findings highlight substantial variation in the evolved collateral effects among replicates, which in turn determine their potential in antibiotic therapy. © The Author 2017. Published by Oxford University Press on

12 CFR 908.32 - Collateral attacks on proceedings under this part.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral attacks on proceedings under this... Rules § 908.32 Collateral attacks on proceedings under this part. If a respondent files in any court a collateral attack that purports to challenge all or any portion of a proceeding under this part, the hearing...

Portal hypertensiv gastropati

DEFF Research Database (Denmark)

Brinch, K; Møller, S; Henriksen, Jens Henrik Sahl

1995-01-01

Portal hypertensive gastropathy (PHG) as defined by congestive changes in the gastric mucosa owing to increased portal pressure, was first described about ten years ago. Whereas definition and grading of severity are still under debate, there is general agreement that PHG is a new clinical entity....... PHG is present in 50-80% of patients with liver cirrhosis. PHG is a major cause of upper gastrointestinal bleeding in patients with portal hypertension (25-90% depending on severity). Presence of portal hypertension is a prerequisite for the development of PHG, and reduction of portal pressure...

Indians' Problems in Acquiring Development Capital. Four Corners Agriculture and Forestry Development Study. Special Report No. 11.

Science.gov (United States)

Fuller, Stephen W.

The difficulty with which American Indians acquire equity capital and an examination of selected Federal programs which make this type of credit available to this minority group are discussed in this report. Specifically, collateral, fractional heirship, ownership of chattels, managerial training, repayment, and servicing of loans are discussed as…

Use of collateral sensitivity networks to design drug cycling protocols that avoid resistance development

DEFF Research Database (Denmark)

Imamovic, Lejla; Sommer, Morten

2013-01-01

collateral sensitivity and resistance profiles, revealing a complex collateral sensitivity network. On the basis of these data, we propose a new treatment framework-collateral sensitivity cycling-in which drugs with compatible collateral sensitivity profiles are used sequentially to treat infection...... pathogens. These results provide proof of principle for collateral sensitivity cycling as a sustainable treatment paradigm that may be generally applicable to infectious diseases and cancer....

Efficacy of collateral types used by financial intermediaries in KwaZulu-Natal

OpenAIRE

Kuhn, M.E.; Darroch, Mark A.G.; Ortmann, Gerald F.

1997-01-01

Collateral is an important incentive device used by lenders to encourage loan repayment. However, collateral must have secure and transferable title, it must be marketable, have low lender liquidation costs and lenders must be able to attach the collateral. Study results for rural and micro-enterprise finance institutions in KwaZulu-Natal showed that assets such as vehicles and equipment were not effective as collateral due to high costs in attaching the asset. Cessions on crops were often co...

Nox2 and p47phox modulate compensatory growth of primary collateral arteries

Science.gov (United States)

DiStasi, Matthew R.; Unthank, Joseph L.

2014-01-01

The role of NADPH oxidase (Nox) in both the promotion and impairment of compensatory collateral growth remains controversial because the specific Nox and reactive oxygen species involved are unclear. The aim of this study was to identify the primary Nox and reactive oxygen species associated with early stage compensatory collateral growth in young, healthy animals. Ligation of the feed arteries that form primary collateral pathways in rat mesentery and mouse hindlimb was used to assess the role of Nox during collateral growth. Changes in mesenteric collateral artery Nox mRNA expression determined by real-time PCR at 1, 3, and 7 days relative to same-animal control arteries suggested a role for Nox subunits Nox2 and p47phox. Administration of apocynin or Nox2ds-tat suppressed collateral growth in both rat and mouse models, suggesting the Nox2/p47phox interaction was involved. Functional significance of p47phox expression was assessed by evaluation of collateral growth in rats administered p47phox small interfering RNA and in p47phox−/− mice. Diameter measurements of collateral mesenteric and gracilis arteries at 7 and 14 days, respectively, indicated no significant collateral growth compared with control rats or C57BL/6 mice. Chronic polyethylene glycol-conjugated catalase administration significantly suppressed collateral development in rats and mice, implying a requirement for H2O2. Taken together, these results suggest that Nox2, modulated at least in part by p47phox, mediates early stage compensatory collateral development via a process dependent upon peroxide generation. These results have important implications for the use of antioxidants and the development of therapies for peripheral arterial disease. PMID:24633549

The Relation between Collateral Circulation and 99mTc-MIBI Heart SPECT

International Nuclear Information System (INIS)

Kim, Jae Man; Na, Deug Young; Park, Eun Kyung

1994-01-01

The coronary collateral vessels have revealed their significance in terms of reduction of infarct size, preservation left ventricular function, and prevention of left ventricular aneurysm in patients with myocardial infarction. The purpose of this study were to evaluated the relation between collateral circulation and 99m Tc-MIBI Heart SPECT in patient with acute myocardial infarction and their clinical significance. The fifty six MI patients with antegrade TIMI perfusion grade 0 and 1 were studied. The patients were classified into two groups; Group I included 30 patients with grade 2, 3 Collateral flow. Group II included 26 patients with grade 0, 1 Collateral flow. Collateral filling were graded from 0 to 3; 0- none, 1- Filling of side branch only, 2- Partial filling of the epicardial segment, 3- Complete filling of epicardial segment. Clinical variables, left ventricular function, 99m Tc-MIBI Heart SPECT were analyzed with angiographic finding. Results were following: 1) Collateral visualization was found to be greater in patient with involvement of right coronary artery (RCA). The collateral development site of infarct related artery was RCA 15 cases, left anterior descending artery (LAD) 10 cases, left circumflex artery (LCX) 5 cases, and the collateral circulation from LAD to RCA was 13 cases (40.6%). 2) There was a tendency to be decreased in peak CK activity with group I . 3) The presence of good collateral channels was more frequently 99m Tc-MIBI reversible perfusion defect (83.4% vs 15.3%, p 99m Tc-MlBI reversible perfusion defect.

47 CFR 1.1907 - Return of property or collateral.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Return of property or collateral. 1.1907 Section 1.1907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Collection of Claims Owed the United States General Provisions § 1.1907 Return of property or collateral...

Rare Disease Video Portal

OpenAIRE

Sánchez Bocanegra, Carlos Luis

2011-01-01

Rare Disease Video Portal (RD Video) is a portal web where contains videos from Youtube including all details from 12 channels of Youtube. Rare Disease Video Portal (RD Video) es un portal web que contiene los vídeos de Youtube incluyendo todos los detalles de 12 canales de Youtube. Rare Disease Video Portal (RD Video) és un portal web que conté els vídeos de Youtube i que inclou tots els detalls de 12 Canals de Youtube.

Aging causes collateral rarefaction and increased severity of ischemic injury in multiple tissues

Science.gov (United States)

Faber, James E.; Zhang, Hua; Lassance-Soares, Roberta M.; Prabhakar, Pranay; Najafi, Amir H.; Burnett, Mary Susan; Epstein, Stephen E.

2011-01-01

Objective Aging is a major risk factor for increased ischemic tissue injury. Whether collateral rarefaction and impaired remodeling contribute to this is unknown. We quantified the number and diameter of native collaterals, and their remodeling in 3-, 16-, 24-, and 31-months-old mice. Methods and Results Aging caused an “age-dose-dependent” greater drop in perfusion immediately after femoral artery ligation, followed by a diminished recovery of flow and increase in tissue injury. These effects were associated with a decline in collateral number, diameter and remodeling. Angiogenesis was also impaired. Mechanistically, these changes were not accompanied by reduced recruitment of T-cells or macrophages to remodeling collaterals. However, eNOS signaling was dysfunctional, as indicated by increased protein nitrosylation and less phosphorylated eNOS and VASP in collateral wall cells. The cerebral circulation exhibited a similar age-dose-dependent loss of collateral number and diameter and increased tortuosity, resulting in an increase in collateral resistance and infarct volume (e.g., 6- and 3-fold, respectively, in 24-months-old mice) after artery occlusion. This was not associated with rarefaction of similarly-sized arterioles. Collateral remodeling was also reduced. Conclusions Our findings demonstrate that aging causes rarefaction and insufficiency of the collateral circulation in multiple tissues, resulting in more severe ischemic tissue injury. PMID:21617137

Historical aspects and relevance of the human coronary collateral circulation.

Science.gov (United States)

Seiler, Christian; Meier, Pascal

2014-02-01

In 1669, anastomoses between the right and left coronary artery were first documented by Richard Lower of Amsterdam. Using post-mortem imaging, a debate followed on the existence of structural inter-coronary anastomoses, which was not resolved before the first half of the 20 ieth century in case of the presence of coronary artery disease (CAD), and not before the early 1960 ies in case of the normal human coronary circulation by William Fulton. Functional coronary collateral measurements during coronary interventions were first performed only in the 1970 ies, respectively in the early 1980 ies. In humans, the existence of functional coronary collaterals in the absence of CAD has not been documented before 2003. Though the coronary collateral circulation has been recognized as an alternative source of blood supply to ischemic myocardium, its prognostic significance for the CAD population as a whole has been controversial until recently. The debate was due to different populations examined (acute versus chronic CAD, varying severity of CAD), to variable definitions of the term "prognosis", to insufficient statistical power of the investigation with rare occurrence of prognostic endpoints, to short duration of follow-up and to blunt instruments employed for collateral assessment. Individually, it has been acknowledged that a well functioning collateral supply to a myocardial area at risk for necrosis reduces infarct size, preserves ventricular function, prevents ventricular remodelling and aneurysm formation. Collectively, evidence has accumulated only recently that an extensive coronary collateral circulation is a beneficial prognosticator quoad vitam. In a recent meta-analysis on the topic, the risk ratio to die from any cause for high vs low or absent collateralization in patients with subacute myocardial infarction was 0.53 (95% confidence interval 0.15-1.92; p=0.335), and for patients with acute myocardial infarction, it was 0.63 (95% confidence interval 0

The association between circulating endothelial progenitor cells and coronary collateral formation.

Science.gov (United States)

Tokgözoğlu, Lale; Yorgun, Hikmet; Gürses, Kadri Murat; Canpolat, Uğur; Ateş, Ahmet Hakan; Tülümen, Erol; Kaya, Ergün Barış; Aytemir, Kudret; Kabakçı, Giray; Tuncer, Murat; Oto, Ali

2011-12-01

We investigated the relationship between coronary collateral formation and circulating endothelial progenitor cells (EPC) in patients undergoing coronary angiography. Circulating CD133(+)/34(+) and CD34(+)/KDR(+) EPCs were determined in 68 patients (normal coronary vessels in 24 patients and coronary artery disease (CAD) in 44 patients) (age: 58.7 ± 10.1, 64.7% male). Circulating EPCs were higher among patients with normal coronary vessels compared to patients with CAD for CD133(+)/34(+) (p collateral formation (p collateral formation after adjustment for other cardiovascular risk factors and extent of CAD (p = 0.037). In patients with severe coronary stenosis, those with increased circulating EPCs had better collateral formation compared to those with lower EPC counts. Our findings implicate that in addition to presence of critical stenosis, intact response of bone marrow is necessary for collateral formation in CAD. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Tissue-engineered collateral ligament composite allografts for scapholunate ligament reconstruction: an experimental study.

Science.gov (United States)

Endress, Ryan; Woon, Colin Y L; Farnebo, Simon J; Behn, Anthony; Bronstein, Joel; Pham, Hung; Yan, Xinrui; Gambhir, Sanjiv S; Chang, James

2012-08-01

In patients with chronic scapholunate (SL) dissociation or dynamic instability, ligament repair is often not possible, and surgical reconstruction is indicated. The ideal graft ligament would recreate both anatomical and biomechanical properties of the dorsal scapholunate ligament (dorsal SLIL). The finger proximal interphalangeal joint (PIP joint) collateral ligament could possibly be a substitute ligament. We harvested human PIP joint collateral ligaments and SL ligaments from 15 cadaveric limbs. We recorded ligament length, width, and thickness, and measured the biomechanical properties (ultimate load, stiffness, and displacement to failure) of native dorsal SLIL, untreated collateral ligaments, decellularized collateral ligaments, and SL repairs with bone-collateral ligament-bone composite collateral ligament grafts. As proof of concept, we then reseeded decellularized bone-collateral ligament-bone composite grafts with green fluorescent protein-labeled adipo-derived mesenchymal stem cells and evaluated them histologically. There was no difference in ultimate load, stiffness, and displacement to failure among native dorsal SLIL, untreated and decellularized collateral ligaments, and SL repairs with tissue-engineered collateral ligament grafts. With pair-matched untreated and decellularized scaffolds, there was no difference in ultimate load or stiffness. However, decellularized ligaments revealed lower displacement to failure compared with untreated ligaments. There was no difference in displacement between decellularized ligaments and native dorsal SLIL. We successfully decellularized grafts with recently described techniques, and they could be similarly reseeded. Proximal interphalangeal joint collateral ligament-based bone-collateral ligament-bone composite allografts had biomechanical properties similar to those of native dorsal SLIL. Decellularization did not adversely affect material properties. These tissue-engineered grafts may offer surgeons another

Collateral flow predicts outcome after basilar artery occlusion : The posterior circulation collateral score

NARCIS (Netherlands)

van der Hoeven, Erik J R J; McVerry, Ferghal; Vos, Jan Albert; Algra, Ale; Puetz, Volker; Kappelle, L. Jaap; Schonewille, Wouter J.

2016-01-01

BACKGROUND AND AIM: Our aim was to assess the prognostic value of a semiquantitative computed tomography angiography-based grading system, for the prediction of outcome in patients with acute basilar artery occlusion, based on the presence of potential collateral pathways on computed tomography

Non-bronchial collateral supply from the left gastric artery in massive haemoptysis

International Nuclear Information System (INIS)

Sellars, N.; Belli, A.M.

2001-01-01

Two patients presented with recurrent, massive haemoptysis. Arteriography, including thoracoabdominal aortograms, revealed in both cases large non-bronchial collaterals arising from the left gastric artery. In the first case the non-bronchial collateral supplied the upper left lobe and in the second case it supplied the middle right lobe. Percutaneous embolisation of bronchial and non-bronchial collateral branches has become an accepted procedure in controlling massive or recurrent haemoptysis. Accurate identification of the non-bronchial collateral arterial feeders is essential for successful embolotherapy. (orig.)

13 CFR 120.395 - What is SBA's collateral position?

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...

Basic dose response of fluorescent screen-based portal imaging device

International Nuclear Information System (INIS)

Yeo, In Hwan; Yonannes, Yonas; Zhu, Yunping

1999-01-01

The purpose of this study is to investigate fundamental aspects of the dose response of fluorescent screen-based electronic portal imaging devices (EPIDs). We acquired scanned signal across portal planes as we varied the radiation that entered the EPID by changing the thickness and anatomy of the phantom as well as the air gap between the phantom and the EPID. In addition, we simulated the relative contribution of the scintillation light signal in the EPID system. We have shown that the dose profile across portal planes is a function of the air gap and phantom thickness. We have also found that depending on the density change within the phantom geometry, errors associated with dose response based on the EPID scan can be as high as 7%. We also found that scintillation light scattering within the EPID system is an important source of error. This study revealed and demonstrated fundamental characteristics of dose response of EPID, as relative to that of ion chambers. This study showed that EPID based on fluorescent screen cannot be an accurate dosimetry system

Coronary Collateral Growth—Back to the Future

OpenAIRE

Chilian, William M.; Penn, Marc S.; Pung, Yuh Fen; Dong, Feng; Mayorga, Maritza; Ohanyan, Vahagn; Logan, Suzanna; Yin, Liya

2011-01-01

The coronary collateral circulation is critically important as an adaptation of the heart to prevent the damage from ischemic insults. In their native state, collaterals in the heart would be classified as part of the microcirculation, existing as arterial-arterial anastomotic connections in the range of 30 to 100 μM in diameter. However, these vessels also show a propensity to remodel into components of the macrocirculation and can become arteries larger than a 1000 μM in diameter. This proc...

Treatment of portal hypertension caused by benign main portal vein stenosis with endovascular stent

International Nuclear Information System (INIS)

Huang Mingsheng; Shan Hong; Jiang Zaibo; Guan Shouhai; Zhu Kangshun; Li Zhengran; Zhou Yubin; He Bingjun

2004-01-01

Objective: To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. Methods: Portal vein stents were implanted in 6 patients with benign main portal vein stenosis (inflammatory stenosis in 3 cases, postprocedure of liver transplantation in another 3 cases). The change of portal vein pressure, the patency of portal vein, relative clinical symptoms, complications, and survival were evaluated. Results: Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in all 6 patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3 ± 4.7) cm H 2 O (1 cm H 2 O=0.098 kPa) to (18.0 ± 1.9) cm H 2 O (P<0.001). The portal blood flow was restored, and the symptoms caused by portal hypertension were eliminated. There was no severe procedure-related complication. Follow-up time was from 5 to 36 months. The portal vein remained patent during the follow-up. All patients survived except one patient who died of other complications of liver transplantation. Conclusion: Percutaneous portal vein stent placement for the treatment of the benign main portal vein stenosis is safe and effective. (authors)

Coronary collateral circulation: clinical significance and influence on survival in patients with coronary artery occlusion

DEFF Research Database (Denmark)

Hansen, J F

1989-01-01

In a consecutive series of 96 patients with coronary artery occlusion, 67 had good and 29 had no or poor collateral circulation. Patients with good collaterals had the severest degree of coronary artery disease. Good collaterals are associated with a higher incidence of angina pectoris and normal...... electrocardiogram and with lower incidence of Q-waves, positive exercise tests, heart failure, previous myocardial infarction, and dyskinesia at ventriculography. Survival rates after 10 years were (1) 51.5% with good and 34.5% with poor collaterals (p less than 0.1), (2) 59.4% with angina pectoris and good...... collaterals and 41.2% with angina pectoris and poor collaterals (p less than 0.05), (3) 64.8% without and 24.4% with heart failure and good collaterals (p less than 0.001), and (4) 58.3% without and 16.1% with heart failure and poor collaterals (p less than 0.01). Good collaterals protect the myocardium...

Time-resolved assessment of collateral flow using 4D CT angiography in large-vessel occlusion stroke

International Nuclear Information System (INIS)

Froelich, Andreas M.J.; Wolff, Sarah Lena; Psychogios, Marios N.; Schramm, Ramona; Knauth, Michael; Schramm, Peter; Klotz, Ernst; Wasser, Katrin

2014-01-01

In acute stroke patients with large vessel occlusion, collateral blood flow affects tissue fate and patient outcome. The visibility of collaterals on computed tomography angiography (CTA) strongly depends on the acquisition phase, but the optimal time point for collateral imaging is unknown. We analysed collaterals in a time-resolved fashion using four-dimensional (4D) CTA in 82 endovascularly treated stroke patients, aiming to determine which acquisition phase best depicts collaterals and predicts outcome. Early, peak and late phases as well as temporally fused maximum intensity projections (tMIP) were graded using a semiquantitative regional leptomeningeal collateral score, compared with conventional single-phase CTA and correlated with functional outcome. The total extent of collateral flow was best visualised on tMIP. Collateral scores were significantly lower on early and peak phase as well as on single-phase CTA. Collateral grade was associated with favourable functional outcome and the strength of this relationship increased from earlier to later phases, with collaterals on tMIP showing the strongest correlation with outcome. Temporally fused tMIP images provide the best depiction of collateral flow. Our findings suggest that the total extent of collateral flow, rather than the velocity of collateral filling, best predicts clinical outcome. (orig.)

Congenital absence of infrarenal IVC and iliac venous system : Unusual collateral Pathways

International Nuclear Information System (INIS)

Lee, Jin Joo; Lee, Byung Hee; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil

1994-01-01

We present a case with congenital absence of the infrarenal portion of inferior vena cava and iliac venous system, showing unusual venous collaterals including the left ovarian venous collateral via parametrial venous complex, and a mesenteric-periureteric venous connection. The venous collateral pathways were demonstrated by computed tomography and venography

Impact of collateral circulation on early outcome and risk of hemorrhagic complications after systemic thrombolysis.

Science.gov (United States)

Brunner, Freimuth; Tomandl, Bernd; Hanken, Katrin; Hildebrandt, Helmut; Kastrup, Andreas

2014-12-01

In stroke patients, collateral flow can rapidly be assessed on computed tomography angiography (CTA). In this study, the impact of baseline collaterals on early outcome and risk of symptomatic intracerebral hemorrhages after systemic thrombolysis in patients with proximal arterial occlusions within the anterior circulation were analyzed. Collateralization scores were determined on the CT angiography source images (0 = absent; 1 ≤ 50%, 2 > 50% but collateral filling) of patients with distal intracranial carotid artery and/or M1 segment occlusions treated from 2008 to December 2011. A collateral score of 0 to 1 was designated as poor and 2 to 3 as good collateral vessel status. Outcome variables included in hospital mortality, favorable outcome at discharge (modified Rankin score ≤ 2), and rates of symptomatic intracerebral hemorrhage based on the European-Australasian Acute Stroke Study II definition. Among 246 subjects (mean age of 74 years; median National Institutes of Health Stroke Scale N at admission 14), 205 patients (83%) had good collaterals, whereas 41 patients (17%) had poor collaterals, respectively. Patients with poor collaterals had significantly higher rates of in-hospital mortality (41% vs. 12%, P collaterals. The grade of collateralization was independently associated with in-hospital mortality (P collaterals have a poor early functional outcome and high rates of symptomatic intracerebral hemorrhage after systemic thrombolysis. Since similar findings have also been reported after endovascular therapy, strategies to improve collateral blood flow should be assessed in this patient population. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.

Iron oxide contrast media improve MR-imaging of the portal venous system -an experimental study

International Nuclear Information System (INIS)

Boeck, J.C.; Knollmann, F.D.; Teltenkoetter, S.; Wlodarcyk, W.; Muehler, A.; Felix, R.

1997-01-01

Purpose: The aim was to demonstrate that intravenous superparamagnetic iron oxide contrast agents improve the delineation of the portal venous system. Material and methods: The portal venous system of 8 minipigs was demonstrated by a FLASH 2-D MRA-sequence. Scans were acquired before and after intravenous administration of 10 and 20 μmol/kg of a superparamagnetic iron oxide contrast agent (SHU 555 A). Signal intensities were measured in the portal vein and hepatic parenchym and contrast-to-noise ratios were calculated. Results: Following a cumulative dose of 10 μmol iron oxide, hepatic parenchymal signal intensity decreased to 67±6%, following 20 μmol to 29±4%, and following 40 μmol to 13±2% of control (p [de

Noncirrhotic portal hypertension.

Science.gov (United States)

Da, Ben L; Koh, Christopher; Heller, Theo

2018-05-01

Noncirrhotic portal hypertension represents a heterogeneous group of liver disorders that is characterized by portal hypertension in the absence of cirrhosis. The purpose of this review is to serve as a guide on how to approach a patient with noncirrhotic portal hypertension with a focus on recent developments. Recent studies pertaining to noncirrhotic portal hypertension have investigated aetiological causes, mechanisms of disease, noninvasive diagnostic modalities, clinical characteristics in the paediatric population and novel treatment targets. Noncirrhotic portal hypertension is an underappreciated clinical entity that can be difficult to diagnosis without a healthy suspicion. Diagnosis then relies on a comprehensive understanding of the causes and clinical manifestations of this disease, as well as a careful interpretation of the liver biopsy. Noninvasive approaches to diagnosis may play a significant role moving forward in this disease. Treatment in NCPH remains largely targeted at the individual sequalae of portal hypertension.

Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease.

Science.gov (United States)

Hartkamp, Nolan S; Petersen, Esben T; Chappell, Michael A; Okell, Thomas W; Uyttenboogaart, Maarten; Zeebregts, Clark J; Bokkers, Reinoud Ph

2017-01-01

Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.

Ketanserin effect on limb perfusion and arterial collaterals

International Nuclear Information System (INIS)

Grassi, C.J.; Janicek, M.; Hollenberg, N.K.; Meyerovitz, M.F.; Harrington, D.P.

1987-01-01

Arterial collateral flow and major vessel patency are important in patients with intermittent claudication. Activity of serotonin released from platelets has been demonstrated experimentally, and serotonin antagonists have been investigated in treadmill testing. Ketanserin, a serotonin (5-HT/sup 2/) antagonist, was investigated in 20 patients with intermittent claudication to assess its effect on collaterals. Blood-pressure ratio (thigh/arm), mercury-strain gauge plethysmography, Doppler pressures, and repeat arteriography were performed. Ketanserin (3-30 μg/kg IA) increased collateral vessel size on angiography in 12 patients (60%) and increased blood-flow ratio and plethysmogrpahy pressures on average. These observations, confirming clinical studies that some patients show a dramatic response and others do not, might prove useful in identifying patients who will respond to ketanserin for occlusive vascular disease

De-novo Collateral Formation Following Acute Myocardial Infarction: Dependence on CCR2+ Bone Marrow Cells

Science.gov (United States)

Zhang, Hua; Faber, James E

2015-01-01

Wide variation exists in the extent (number and diameter) of native pre-existing collaterals in tissues of different strains of mice, with supportive indirect evidence recently appearing for humans. This variation is a major determinant of the wide variation in severity of tissue injury in occlusive vascular disease. Whether such genetic-dependent variation also exists in the heart is unknown because no model exists for study of mouse coronary collaterals. Also owing to methodological limitations, it is not known if ischemia can induce new coronary collaterals to form (“neo-collaterals”) versus remodeling of pre-existing ones. The present study sought to develop a model to study coronary collaterals in mice, determine whether neo-collateral formation occurs, and investigate the responsible mechanisms. Four strains with known rank-ordered differences in collateral extent in brain and skeletal muscle were studied: C57BLKS>C57BL/6>A/J>BALB/c. Unexpectedly, these and 5 additional strains lacked native coronary collaterals. However after ligation, neo-collaterals formed rapidly within 1-to-2 days, reaching their maximum extent in ≤ 7 days. Rank-order for neo-collateral formation differed from the above: C57BL/6>BALB/c>C57BLKS>A/J. Collateral network conductance, infarct volume−1, and contractile function followed this same rank-order. Neo-collateral formation and collateral conductance were reduced and infarct volume increased in MCP1−/− and CCR2−/− mice. Bone-marrow transplant rescued collateral formation in CCR2−/− mice. Involvement of fractalkine→CX3CR1 signaling and endothelial cell proliferation were also identified. This study introduces a model for investigating the coronary collateral circulation in mice, demonstrates that neocollaterals form rapidly after coronary occlusion, and finds that MCP→CCR2-mediated recruitment of myeloid cells is required for this process. PMID:26254180

Validation of quality control tests of a multi leaf collimator using electronic portal image devices and commercial software; Validacion de unas pruebas de control de calidad del colimador multilamina utilizando dispositivos electronicos de imagen portal y una aplicacion comercial

Energy Technology Data Exchange (ETDEWEB)

Latorre-Musoll, A.; Jornet Sala, N.; Carrasco de Fez, P.; Edualdo Puell, T.; Ruiz Martinez, A.; Ribas Morales, M.

2013-07-01

We describe a daily quality control procedure of the multi leaf collimator (MLC) based on electronic portal image devices and commercial software. We designed tests that compare portal images of a set of static and dynamic MLC configurations to a set of reference images using commercial portal dosimetry software. Reference images were acquired using the same set of MLC configurations after the calibration of the MLC. To assess the sensitivity to detect MLC under performances, we modified the MLC configurations by inserting a range of leaf position and speed errors. Distance measurements on portal images correlated with leaf position errors down to 0.1 mm in static MLC configurations. Dose differences between portal images correlated both with speed errors down to 0.5% of the nominal leaf velocities and with leaf position errors down to 0.1 mm in dynamic MLC configurations. The proposed quality control procedure can assess static and dynamic MLC configurations with high sensitivity and reliability. (Author)

Associations Between Collateral Status and Thrombus Characteristics and Their Impact in Anterior Circulation Stroke.

Science.gov (United States)

Alves, Heitor C; Treurniet, Kilian M; Dutra, Bruna G; Jansen, Ivo G H; Boers, Anna M M; Santos, Emilie M M; Berkhemer, Olvert A; Dippel, Diederik W J; van der Lugt, Aad; van Zwam, Wim H; van Oostenbrugge, Robert J; Lingsma, Hester F; Roos, Yvo B W E M; Yoo, Albert J; Marquering, Henk A; Majoie, Charles B L M

2018-02-01

Thrombus characteristics and collateral score are associated with functional outcome in patients with acute ischemic stroke. It has been suggested that they affect each other. The aim of this study is to evaluate the association between clot burden score, thrombus perviousness, and collateral score and to determine whether collateral score influences the association of thrombus characteristics with functional outcome. Patients with baseline thin-slice noncontrast computed tomography and computed tomographic angiography images from the MR CLEAN trial (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands) were included (n=195). Collateral score and clot burden scores were determined on baseline computed tomographic angiography. Thrombus attenuation increase was determined by comparing thrombus density on noncontrast computed tomography and computed tomographic angiography using a semiautomated method. The association of collateral score with clot burden score and thrombus attenuation increase was evaluated with linear regression. Mediation and effect modification analyses were used to assess the influence of collateral score on the association of clot burden score and thrombus attenuation increase with functional outcome. A higher clot burden score (B=0.063; 95% confidence interval, 0.008-0.118) and a higher thrombus attenuation increase (B=0.014; 95% confidence interval, 0.003-0.026) were associated with higher collateral score. Collateral score mediated the association of clot burden score with functional outcome. The association between thrombus attenuation increase and functional outcome was modified by the collateral score, and this association was stronger in patients with moderate and good collaterals. Patients with lower thrombus burden and higher thrombus perviousness scores had higher collateral score. The positive effect of thrombus perviousness on clinical outcome was only present in patients with

Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease

DEFF Research Database (Denmark)

Hartkamp, Nolan S; Petersen, Esben T; Chappell, Michael A

2018-01-01

Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment...... is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial....... In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment....

Huge Varicose Inferior Mesenteric Vein: an Unanticipated 99mTc-labeled Red Blood Cell Scintigraphy Finding

International Nuclear Information System (INIS)

Hoseinzadeh, Samaneh; Shafiei, Babak; Salehian, Mohamadtaghi; Neshandar Asli, Isa; Ghodoosi, Iraj

2010-01-01

Ectopic varices (EcV) are enlarged portosystemic venous collaterals, which usually develop secondary to portal hypertension (PHT). Mesocaval collateral vessels are unusual pathways to decompress the portal system. Here we report the case of a huge varicose inferior mesenteric vein (IMV) that drained into peri rectal collateral veins, demonstrated by 99m Tc-labeled red blood cell (RBC) scintigraphy performed for lower gastrointestinal (GI) bleeding in a 14-year-old girl. This case illustrates the crucial role of 99m Tc-labeled RBC scintigraphy for the diagnosis of rare ectopic lower GI varices.

Huge Varicose Inferior Mesenteric Vein: an Unanticipated {sup 99m}Tc-labeled Red Blood Cell Scintigraphy Finding

Energy Technology Data Exchange (ETDEWEB)

Hoseinzadeh, Samaneh; Shafiei, Babak; Salehian, Mohamadtaghi; Neshandar Asli, Isa; Ghodoosi, Iraj [Shaheed Beheshti Medical University, Tehran (Iran, Islamic Republic of)

2010-09-15

Ectopic varices (EcV) are enlarged portosystemic venous collaterals, which usually develop secondary to portal hypertension (PHT). Mesocaval collateral vessels are unusual pathways to decompress the portal system. Here we report the case of a huge varicose inferior mesenteric vein (IMV) that drained into peri rectal collateral veins, demonstrated by {sup 99m}Tc-labeled red blood cell (RBC) scintigraphy performed for lower gastrointestinal (GI) bleeding in a 14-year-old girl. This case illustrates the crucial role of {sup 99m}Tc-labeled RBC scintigraphy for the diagnosis of rare ectopic lower GI varices.

Relationship Between Collateral Status, Contrast Transit, and Contrast Density in Acute Ischemic Stroke.

Science.gov (United States)

Kawano, Hiroyuki; Bivard, Andrew; Lin, Longting; Spratt, Neil J; Miteff, Ferdinand; Parsons, Mark W; Levi, Christopher R

2016-03-01

Collateral circulation is recognized to influence the life expectancy of the ischemic penumbra in acute ischemic stroke. The best method to quantify collateral status on acute imaging is uncertain. We aimed to determine the relationship between visual collateral status, quantitative collateral assessments, baseline computed tomographic perfusion measures, and tissue outcomes on follow-up imaging. Sixty-six consecutive patients with acute ischemic stroke clinically eligible for recanalization therapy and with M1 or M2 middle cerebral artery occlusion were evaluated. We compared the visual collateral scoring with measures of contrast peak time delay and contrast peak density. We also compared these measures for their ability to predict perfusion lesion and infarct core volumes, final infarct, and infarct growth. Shorter contrast peak time delay (P=0.041) and higher contrast peak density (P=0.002) were associated with good collateral status. Shorter contrast peak time delay correlated with higher contrast peak density (β=-4.413; P=0.037). In logistic regression analysis after adjustment for age, sex, onset-computed tomographic time, and occlusion site, higher contrast peak density was independently associated with good collateral status (P=0.009). Multiple regression analysis showed that higher contrast peak density was an independent predictor of smaller perfusion lesion volume (P=0.029), smaller ischemic core volume (P=0.044), smaller follow-up infarct volume (P=0.005), and smaller infarct growth volume (P=0.010). Visual collateral status, contrast peak density, and contrast peak time delay were inter-related, and good collateral status was strongly associated with contrast peak density. Contrast peak density in collateral vessel may be an important factor in tissue fate in acute ischemic stroke. © 2016 American Heart Association, Inc.

Coronary collaterals and risk for restenosis after percutaneous coronary interventions: a meta-analysis

Directory of Open Access Journals (Sweden)

Meier Pascal

2012-06-01

Full Text Available Abstract Background The benefit of the coronary collateral circulation (natural bypass network on survival is well established. However, data derived from smaller studies indicates that coronary collaterals may increase the risk for restenosis after percutaneous coronary interventions. The purpose of this systematic review and meta-analysis of observational studies was to explore the impact of the collateral circulation on the risk for restenosis. Methods We searched the MEDLINE, EMBASE and ISI Web of Science databases (2001 to 15 July 2011. Random effects models were used to calculate summary risk ratios (RR for restenosis. The primary endpoint was angiographic restenosis > 50%. Results A total of 7 studies enrolling 1,425 subjects were integrated in this analysis. On average across studies, the presence of a good collateralization was predictive for restenosis (risk ratio (RR 1.40 (95% CI 1.09 to 1.80; P = 0.009. This risk ratio was consistent in the subgroup analyses where collateralization was assessed with intracoronary pressure measurements (RR 1.37 (95% CI 1.03 to 1.83; P = 0.038 versus visual assessment (RR 1.41 (95% CI 1.00 to 1.99; P = 0.049. For the subgroup of patients with stable coronary artery disease (CAD, the RR for restenosis with 'good collaterals' was 1.64 (95% CI 1.14 to 2.35 compared to 'poor collaterals' (P = 0.008. For patients with acute myocardial infarction, however, the RR for restenosis with 'good collateralization' was only 1.23 (95% CI 0.89 to 1.69; P = 0.212. Conclusions The risk of restenosis after percutaneous coronary intervention (PCI is increased in patients with good coronary collateralization. Assessment of the coronary collateral circulation before PCI may be useful for risk stratification and for the choice of antiproliferative measures (drug-eluting stent instead bare-metal stent, cilostazol.

The feasible study of vasodilators in portal vein targeting infusion for treating portal hypertension

International Nuclear Information System (INIS)

Wu Hanping; Liang Huiming; Zheng Chuansheng; Feng Gansheng

2002-01-01

Objective: To find out the ideal portal vein tar getting injection routes for portal hypertension treatment. Methods: 28 cirrhotic rat models with portal hypertension induced by CCl 4 were divided into 4 groups: inferior caval vein injection group, portal vein injection group, hepatic artery injection group, spleen injection group. The changes in portal vein pressure (PVP), inferior caval vein pressure (ICVP), mean artery pressure (MAP) and heart rate (HR) were monitored before and after prazosin injection. Results: After intra-portal, intra-hepatic arterial or spleen injection of prazosin, larger decrease in PVP and lesser effects on MAP than intravenous injection had been induced. The effect on HR showed no difference among these four groups. Conclusions: Hepatic artery and spleen prazosin administration have the same advantages on treatment of portal hypertension as those of intra-portal infusion, that is the greater decrease on portal vein pressure, the lesser effects on systemic hemodynamics. Vasodilation drugs for hepatic artery infusion through percutaneous port catheter system by hepatic artery implantation would be an ideal method for portal hypertension treatment

Light scattering changes follow evoked potentials from hippocampal Schaeffer collateral stimulation

DEFF Research Database (Denmark)

Rector, D M; Poe, G R; Kristensen, Morten Pilgaard

1997-01-01

, concurrently with larger population postsynaptic potentials. Optical signals occurred over a time course similar to that for electrical signals and increased with larger stimulation amplitude to a maximum, then decreased with further increases in stimulation current. Camera images revealed a topographic......We assessed relationships of evoked electrical and light scattering changes from cat dorsal hippocampus following Schaeffer collateral stimulation. Under anesthesia, eight stimulating electrodes were placed in the left hippocampal CA field and an optic probe, coupled to a photodiode or a charge....... Electrode recordings and photodiode output were simultaneously acquired at 2.4 kHz during single biphasic pulse stimuli 0.5 ms in duration with 0.1-Hz intervals. Camera images were digitized at 100 Hz. An average of 150 responses was calculated for each of six stimulating current levels. Stimuli elicited...

On the Possible Interaction Mechanism between Collateral Vessels and Restenosis

NARCIS (Netherlands)

Zun, P.S.; Hoekstra, A.G.

2015-01-01

Several clinical studies and their meta-analysis suggest that developed collateral vessels in the heart correlate to an increased risk of in-stent restenosis. The possible physiological interaction between the collateral development and in-stent restenosis is investigated in this study. Based on

Pricing a Collateralized Derivative Trade with a Funding Value Adjustment

Directory of Open Access Journals (Sweden)

Chadd B. Hunzinger

2015-01-01

Full Text Available The 2008 credit crisis changed the manner in which derivative trades are conducted. One of these changes is the posting of collateral in a trade to mitigate the counterparty credit risk. Another is the realization that banks are not risk-free and, as a result, cannot borrow at the risk-free rate any longer. The latter led banks to introduced the controversial adjustment to derivative prices, known as a funding value adjustment (FVA, which is interlinked with the posting of collateral. In this paper, we extend the Cox, Ross and Rubinstein (CRR discrete-time model to include collateral and FVA. We prove that this derived model is a discrete analogue of Piterbarg’s partial differential equation (PDE, which describes the price of a collateralized derivative. The fact that the two models coincide is also verified by numerical implementation of the results that we obtain.

Portal vein thrombosis.

Science.gov (United States)

Chawla, Yogesh K; Bodh, Vijay

2015-03-01

Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion.

Trombosis portal y mesentérica asociada al déficit de la proteína S Portal and mesenteric thrombosis associated with protein S deficiency

Directory of Open Access Journals (Sweden)

J. A. Chirinos Vega

2008-02-01

gastrointestinal bleeding. She reported mild, diffuse abdominal pain in the last 2 weeks. Endoscopy revealed ruptured esophageal varices. Doppler ultrasonography and CT demonstrated a heterogeneous liver, splenomegaly and ascites, and complete non-occlusive PT involving the hilum and portal branches, as well as the superior mesenteric vein, with portosystemic collaterals. At this point a complete study for cirrhosis etiologies was negative, including a liver biopsy that showed nonspecific architectural changes secondary to diminished blood flow, which suggested non-cirrhotic portal hypertension. The search for hypercoagulability states determined a deficiency of S protein, with total pS = 107% and free pS = 56%. The patient was started on anticoagulant treatment and no other thrombotic events occurred. Discussion: PT usually manifests without specific symptoms. The most common presentation is upper gastrointestinal bleeding, as occurred in our patient. Liver cirrhosis is one of the most frequent cause of PT. Up to 65% of these patients present an associated prothrombotic state, including protein S deficiency. Our case reminds us of the importance of a systematic search for hipercoagulability syndromes in patients with TP, even when the etiology can be conferred to liver cirrhosis.

Collateral flow after extracorporeal membrane oxygenation

International Nuclear Information System (INIS)

Smith, A.S.; Wiznitzer, M.; Haacke, E.M.

1990-01-01

MR angiography was used to evaluate collateral flow after extracorporal membrane oxygenation (ECMO) in patients with permanent ligation of the right common carotid artery (RCCA). One year after ECMO, MR angiography of the cerebral circulation was performed in 11 survivors and MR angiography of the neck in seven. The diameters of the left common carotid (LCCA) and vertebral (Vert) arteries in the neck and of the basilar (Bas) and internal carotid arteries in the head were measured. Ratios of the artery diameters were compared with those of seven children (aged 6 months - 17 years) who had normal MR angiographic and brain MR imaging studies. Compared with carotid artery diameter, the ECMO population had proportionately larger vertebral (RVert/LCCA, -0.82 ± 0.12 vs 0.56 ± 0.20 [<.02], LVert/LCCA, -0.86 ± 0.15 vs 0.67 ± 0.05 [P < .02] and basilar artery diameters (LICA/Bas, -0.91 ± 0.15 vs 1.49 ± 0.48 [p < .003]) than did control subjects. Ratios in five children with enlarged RPComA after ECMO were not significantly different from those in controls. The RICA was present and smaller than the LICA in the ECMO population, but not in control subjects (RICA/LICA, -0.75 ± 0.06 vs 0.91 ± 0.23 [p < .05]). Increased vertebral and basilar artery flow is a response to RCCA ligation in the neonate and is independent of RPComA collateral flow. This suggests the presence of more extensive parenchymal collaterals from posterior cerebral arteries, from the vertebrobasilar circulation to the external carotid artery or other collaterals. Consequently, later abnormalities of vertebrobasilar flow might adversely affect right hemispheric function in this children

Injuries to the Collateral Ligaments of the Metacarpophalangeal Joint of the Thumb, Including Simultaneous Combined Thumb Ulnar and Radial Collateral Ligament Injuries, in National Football League Athletes.

Science.gov (United States)

Werner, Brian C; Belkin, Nicole S; Kennelly, Steve; Weiss, Leigh; Barnes, Ronnie P; Rodeo, Scott A; Warren, Russell F; Hotchkiss, Robert N

2017-01-01

Thumb collateral ligament injuries occur frequently in the National Football League (NFL). In the general population or in recreational athletes, pure metacarpophalangeal (MCP) abduction or adduction mechanisms yield isolated ulnar collateral ligament (UCL) and radial collateral ligament (RCL) tears, respectively, while NFL athletes may sustain combined mechanism injury patterns. To evaluate the incidence of simultaneous combined thumb UCL and RCL tears among all thumb MCP collateral ligament injuries in NFL athletes on a single team. Case series; Level of evidence, 4. A retrospective review of all thumb injuries on a single NFL team from 1991 to 2014 was performed. All players with a thumb MCP collateral ligament injury were included. Collateral ligament injuries were confirmed by review of both physical examination findings and magnetic resonance imaging. Player demographics, surgical details, and return-to-play data were obtained from the team electronic medical record and surgeons' records. A total of 36 thumbs in 32 NFL players were included in the study, yielding an incidence of 1.6 thumb MCP collateral ligament injuries per year on a single NFL team. Of these, 9 thumbs (25%) had a simultaneous combined UCL and RCL tear injury pattern confirmed on both physical examination and MRI. The remaining 27 thumbs (75%) were isolated UCL injuries. All combined UCL/RCL injuries required surgery due to dysfunction from instability; 63.0% of isolated UCL injuries required surgical repair ( P = .032) due to continued pain and dysfunction from instability. Repair, when required, was delayed until the end of the season. All players with combined UCL/RCL injuries and isolated UCL injuries returned to play professional football the following season. Simultaneous combined thumb UCL and RCL tear is a previously undescribed injury pattern that occurred in 25% of thumb MCP collateral ligament injuries on a single NFL team over a 23-year period. All players with combined thumb UCL

Collateral Informant Assessment in Alcohol Use Research Involving College Students

Science.gov (United States)

Hagman, Brett T.; Cohn, Amy M.; Noel, Nora E.; Clifford, Patrick R.

2010-01-01

Objective: This study examined the associations between college students' self-reported alcohol use and corresponding collateral reports and identified factors that influence agreement between both sets of reports. Participants/Methods: Subject-collateral pairs (N = 300) were recruited from undergraduate psychology courses. Results: Data yielded…

Value of Quantitative Collateral Scoring on CT Angiography in Patients with Acute Ischemic Stroke.

Science.gov (United States)

Boers, A M M; Sales Barros, R; Jansen, I G H; Berkhemer, O A; Beenen, L F M; Menon, B K; Dippel, D W J; van der Lugt, A; van Zwam, W H; Roos, Y B W E M; van Oostenbrugge, R J; Slump, C H; Majoie, C B L M; Marquering, H A

2018-06-01

Many studies have emphasized the relevance of collateral flow in patients presenting with acute ischemic stroke. Our aim was to evaluate the relationship of the quantitative collateral score on baseline CTA with the outcome of patients with acute ischemic stroke and test whether the timing of the CTA acquisition influences this relationship. From the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) data base, all baseline thin-slice CTA images of patients with acute ischemic stroke with intracranial large-vessel occlusion were retrospectively collected. The quantitative collateral score was calculated as the ratio of the vascular appearance of both hemispheres and was compared with the visual collateral score. Primary outcomes were 90-day mRS score and follow-up infarct volume. The relation with outcome and the association with treatment effect were estimated. The influence of the CTA acquisition phase on the relation of collateral scores with outcome was determined. A total of 442 patients were included. The quantitative collateral score strongly correlated with the visual collateral score (ρ = 0.75) and was an independent predictor of mRS (adjusted odds ratio = 0.81; 95% CI, .77-.86) and follow-up infarct volume (exponent β = 0.88; P quantitative collateral score showed areas under the curve of 0.71 and 0.69 for predicting functional independence (mRS 0-2) and follow-up infarct volume of >90 mL, respectively. We found significant interaction of the quantitative collateral score with the endovascular therapy effect in unadjusted analysis on the full ordinal mRS scale ( P = .048) and on functional independence ( P = .049). Modification of the quantitative collateral score by acquisition phase on outcome was significant (mRS: P = .004; follow-up infarct volume: P quantitative collateral scoring in patients with acute ischemic stroke is a reliable and user-independent measure of the collateral

Sonographic findings in the Cruveilhier-von Baumgarten syndrome

Energy Technology Data Exchange (ETDEWEB)

Pirschel, J

1982-07-01

Portal hypertension is the most common complication of cirrhosis of the liver and leads to a reversal of blood flow and re-opening of pre-formed portal-systemic collaterals. Amongst a variety of possible hepato-fugal collaterals, the Cruveilhier-von Baumgarten syndrome, consisting of the reopening of umbilical veins, is a rare variant. It has been possible to demonstrate this clearly by sonography in 18 patients.

Collateral veins in left renal vein stenosis demonstrated via CT

Energy Technology Data Exchange (ETDEWEB)

Lien, H.H.; Lund, G.; Talle, K.

1983-02-01

Twelve patients with left renal vein stenosis from tumor compression were studied with CT. All had distended collateral veins in the perirenal space which either formed a radiating or a cobweb pattern or appeared as marked longitudinal veins. Inferior phrenic vein branches were seen in seven patients and were considerably enlarged in two. Other major veins possibly taking part in collateral circulation could not be recognized due to obliteration of fat planes. The renal fascia was thickened in eleven patients, probably due to edema. A close study of the perirenal space with CT may give valuable information about collateral development.

Collateral veins in left renal vein stenosis demonstrated via CT

International Nuclear Information System (INIS)

Lien, H.H.; Lund, G.; Talle, K.

1983-01-01

Twelve patients with left renal vein stenosis from tumor compression were studied with CT. All had distended collateral veins in the perirenal space which either formed a radiating or a cobweb pattern or appeared as marked longitudinal veins. Inferior phrenic vein branches were seen in seven patients and were considerably enlarged in two. Other major veins possibly taking part in collateral circulation could not be recognized due to obliteration of fat planes. The renal fascia was thickened in eleven patients, probably due to edema. A close study of the perirenal space with CT may give valuable information about collateral development. (orig.)

Significance of collateral vessels on the prediction of superior vena cava syndrome on CT

International Nuclear Information System (INIS)

Kim, Hyun Sook; Kim, Hyung Jin; Lee, Hyeng Gon; Ahn, In Oak; Chung, Sung Hoon

1993-01-01

Although visible collateral vessels on computed tomography (CT) has been considered as an important finding in superior vena cava (SVC) syndrome, there is no systematical analysis concerning correlation between the CT evidence of collateral vessels and clinical evidence of SVC syndrome. The purpose of this study is to evaluate how accurately we predict the clinical presence of SVC syndrome by the collateral vessels in patients with apparent SVC obstruction in CT. Forty seven patients having a CT evidence of obstruction or compression of SVC and/or its major tributaries were included in this study. Lung cancer was the most common underlying disease (n=40). The enhanced CT scans were obtained through either arm vein using a combined bolus and drip-infusion technique. Analyzing the CT scans, we particularly paid attention to the site and pattern of venous compromise, presence of collateral vessels, and if present, their location, without knowing whether symptoms and sign were present or nor, and then compared them with clinical data by a thorough review of charts, To verify the frequency of visible collateral vessels in normal subjects, we also evaluated the CT scans of 50 patients without mediastinal disease and clinical SVC syndrome as a control group. On CT, collateral vessels were found in 24 patients, among whom three patient had a single collateral and 21 patients had two or more collateral channels. There were two false positive cases, in which clinically overt SVC syndrome appeared 10 days and three months after CT examination respectively, and one false negative case. The presence of collateral vessels on CT, respectively, and one false negative case. The presence of collateral vessels on CT, regardless of the number and location of collateral vessels and pattern of venous obstruction, was a good clue for predicting the presence of clinical SVC syndrome with the sensitivity and the specificity of 95.7% and 91.7%, respectively. In control group, collateral

Collateral and SME financing in Bangladesh: An analysis across bank size and bank ownership types

OpenAIRE

Rahman, Ashiqur; Rahman, Mosiqure Twyeafur; Ključnikov, Aleksandr

2016-01-01

We examine the issue of pledging collateral and its effect on access to credit, interest rates and credit risk of SMEs financing in Bangladesh with respect to bank size. We also examine the collateral classification (fixed assets collateral, personal guarantee and third-party guarantee) by bank ownership types to find what types of collateral are preferred by public, private and foreign banks in Bangladesh for lending to firms. In addition to that, we examine whether collateral requirements a...

Collateral status affects the onset-to-reperfusion time window for good outcome.

Science.gov (United States)

Kim, Byung Moon; Baek, Jang-Hyun; Heo, Ji Hoe; Nam, Hyo Suk; Kim, Young Dae; Yoo, Joonsang; Kim, Dong Joon; Jeon, Pyoung; Baik, Seung Kug; Suh, Sang Hyun; Lee, Kyung Yol; Kwak, Hyo Sung; Roh, Hong Gee; Lee, Young-Jun; Kim, Sang Heum; Ryu, Chang-Woo; Ihn, Yon-Kwon; Kim, Byungjoon; Jeon, Hong Jun; Kim, Jin Woo; Byun, Jun Soo; Suh, Sangil; Park, Jeong Jin; Lee, Woong Jae; Roh, Jieun; Shin, Byoung-Soo; Bang, Oh Young

2018-03-08

To characterise the time window in which endovascular thrombectomy (EVT) is associated with good outcome, and to test the differential relationship between functional outcome and onset-to-reperfusion time (ORT), depending on collateral status. This was a retrospective analysis of clinical and imaging data of 554 consecutive patients, who had recanalisation success by EVT for anterior circulation large artery occlusion, from the prospectively maintained registries of 16 comprehensive stroke centres between September 2010 and December 2015. The patients were dichotomised into good and poor collateral groups, based on CT angiography. We tested whether the likelihood of good outcome (modified Rankin Scale, 0-2) by ORT was different between two groups. ORT was 298 min±113 min (range, 81-665 min), and 84.5% of patients had good collaterals. Age, diabetes mellitus, previous infarction, National Institutes of Health Stroke Scale, good collaterals (OR 40.766; 95% CI 10.668 to 155.78; pcollateral group (OR 0.305 for every 30 min; 95% CI 0.113 to 0.822) than in good collateral group (OR 0.926 for every 30 min; 95% CI 0.875 to 0.980). Earlier successful recanalisation was strongly associated with good outcome in poor collateral group; however, this association was weak during the tested time window in good collateral group. This suggests that the ORT window for good outcome can be adjusted according to collateral status. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Macronodular hepatic tuberculosis associated with portal vein thrombosis and portal hypertension

International Nuclear Information System (INIS)

Venkatesh, S.K.; Tan, L.K.A.; Siew, E.P.Y.; Putti, T.C.

2005-01-01

Tuberculosis (TB) of the liver is usually associated with miliary spread. Macronodular TB of the liver is rare. A case of macronodular TB of the liver in a 31-year-old woman causing portal vein thrombosis and portal hypertension is presented. Ultrasound and CT appearances are described. There was coexistent ileo-caecal TB with extensive mesenteric and retroperitoneal lymphadenopathy. Macronodular TB should be considered in the differential diagnosis when a patient presents with multiple calcified masses in the liver with portal vein thrombosis and portal hypertension. Copyright (2005) Blackwell Science Pty Ltd

Usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis

International Nuclear Information System (INIS)

Tsukune, Yoshihiko

1984-01-01

This study assesses the usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis. Seventy-eight patients with liver cirrhosis underwent both CT and angiography. Comparison was made between CT and angiography on eleven types of collaterals, and many of them were demonstrated on CT scans better than angio. Especially, esophageal varices, paraesophageal varices, umbilical pathway and caput medusa were diagnostic on CT scans. Gastrorenal collaterals, splenorenal collaterals, retroperitoneal pathway are also well demonstrated. Dilatation of azygos systems and small veins in the liver surface are only observed on CT scans. However, coronary varices and short gastric varices are well diagnostic in angiography. But considering all types of collaterals, it was stressed that angiography can be eliminated by CT in evaluation of collaterals in liver cirrhosis. (author)

Retrospective analysis of intravertebral collateral enhancement in patients with central venous obstruction

International Nuclear Information System (INIS)

Simeone, F.J.; Chang, Connie Y.; Huang, Ambrose J.; Kattapuram, Susan V.; Bredella, Miriam A.; Torriani, Martin; Bennett, Debbie L.

2016-01-01

To compare prevalence and patterns of intravertebral collateral enhancement in patients with and without central venous obstruction (CVO). Chest CTs performed between 1/1/2000 and 12/15/2012 with reports containing terms indicating CVO were identified. All contrast enhanced CTs were examined for the presence of CVO and collateral venous pathways. If intravertebral collateral enhancement was present, the pattern was recorded as nodular, linear, or both. In 209 suspected cases of CVO, 53 (25 %) were confirmed with obstruction and 156 (75 %) were without obstruction. In patients with CVO, 47 % (25/53) demonstrated collateral venous flow through an intravertebral marrow pathway compared to 5 % (8/156) of patients without CVO (P < 0.0001). The most common level of enhancement was the upper thoracic spine, involving only the vertebral body. Nodular, linear, and combined nodular-linear enhancement patterns were seen with similar frequency. Nodular intravertebral collateral enhancement was mistaken for sclerotic metastases in 33 % (3/9) of cases. Intravertebral collateral enhancement was seen in almost half the patients with CVO and when nodular enhancement is present, it is important to differentiate between metastatic lesions and enhancement related to CVO. (orig.)

Retrospective analysis of intravertebral collateral enhancement in patients with central venous obstruction

Energy Technology Data Exchange (ETDEWEB)

Simeone, F.J.; Chang, Connie Y.; Huang, Ambrose J.; Kattapuram, Susan V.; Bredella, Miriam A.; Torriani, Martin [Massachusetts General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Boston, MA (United States); Bennett, Debbie L. [Saint Louis University School of Medicine, Department of Radiology, Saint Louis, MO (United States)

2016-02-15

To compare prevalence and patterns of intravertebral collateral enhancement in patients with and without central venous obstruction (CVO). Chest CTs performed between 1/1/2000 and 12/15/2012 with reports containing terms indicating CVO were identified. All contrast enhanced CTs were examined for the presence of CVO and collateral venous pathways. If intravertebral collateral enhancement was present, the pattern was recorded as nodular, linear, or both. In 209 suspected cases of CVO, 53 (25 %) were confirmed with obstruction and 156 (75 %) were without obstruction. In patients with CVO, 47 % (25/53) demonstrated collateral venous flow through an intravertebral marrow pathway compared to 5 % (8/156) of patients without CVO (P < 0.0001). The most common level of enhancement was the upper thoracic spine, involving only the vertebral body. Nodular, linear, and combined nodular-linear enhancement patterns were seen with similar frequency. Nodular intravertebral collateral enhancement was mistaken for sclerotic metastases in 33 % (3/9) of cases. Intravertebral collateral enhancement was seen in almost half the patients with CVO and when nodular enhancement is present, it is important to differentiate between metastatic lesions and enhancement related to CVO. (orig.)

Cognitive assessment of older adults in general practice: the collateral history.

Science.gov (United States)

Dyer, Adam H; Foley, Tony; O'Shea, Brendan; Kennelly, Sean P

2017-12-02

The collateral (or informant) history is a key component in the assessment of older adults presenting with a memory problem or concern over cognition. Despite this, it rarely features in medical literature and academic curricula. Its role in general practice has never been assessed. The aim of this study is to assess the role of the collateral history in the investigation of cognitive impairment in general practice. An online survey distributed to three nationally representative cohorts of GPs in Ireland (n = 692). Ninety-five (14%; 52.2% male) responded. Nearly all (87%; 83/95) indicate that it is most often a family member who brings possible cognitive impairment to the attention of their GP. The vast majority obtain a collateral history in > 90% of cases (72.6%; 69/95) and rate it very useful in their clinical assessment of cognition. GPs report the collateral history as readily available and rarely refused, with the general practice environment well-suited to obtaining collateral histories. A small minority routinely use the GPCOG informant section (3.2%; 3/95). Nearly all (92.6%; 88/95) report having received no training in obtaining collateral histories with most (79%; 75/95) welcoming of further training in this area. Despite recognition of the utility and importance of the collateral history, the vast majority of GPs report having never received training in obtaining one and do not use structured tools to guide their interview. Further emphasis on the informant history as a distinct clinical entity on medical curricula and increasing emphasis on the availability of structured informant tools are warranted.

Collateral blood flow in different cerebrovascular hierarchy provides endogenous protection in cerebral ischemia.

Science.gov (United States)

Luo, Chuanming; Liang, Fengyin; Ren, Huixia; Yao, Xiaoli; Liu, Qiang; Li, Mingyue; Qin, Dajiang; Yuan, Ti-Fei; Pei, Zhong; Su, Huanxing

2017-11-01

Collateral blood flow as vascular adaptions to focal cerebral ischemia is well recognized. However, few studies directly investigate the dynamics of collateral vessel recruitment in vivo and little is known about the effect of collateral blood flow in different cerebrovascular hierarchy on the neuropathology after focal ischemic stroke. Here, we report that collateral blood flow is critically involved in blood vessel compensations following regional ischemia. We occluded a pial arteriole using femtosecond laser ablating under the intact thinned skull and documented the changes of collateral flow around the surface communication network and between the surface communication network and subsurface microcirculation network using in vivo two photon microscopy imaging. Occlusion of the pial arteriole apparently increased the diameter and collateral blood flow of its leptomeningeal anastomoses, which significantly reduced the cortical infarction size. This result suggests that the collateral flow via surface communicating network connected with leptomeningeal anastomoses could greatly impact on the extent of infarction. We then further occluded the target pial arteriole and all of its leptomeningeal anastomoses. Notably, this type of occlusion led to reversals of blood flow in the penetrating arterioles mainly proximal to the occluded pial arteriole in a direction from the subsurface microcirculation network to surface arterioles. Interesting, the cell death in the area of ischemic penumbra was accelerated when we performed occlusion to cease the reversed blood flow in those penetrating arterioles, suggesting that the collateral blood flow from subsurface microcirculation network exerts protective roles in delaying cell death in the ischemic penumbra. In conclusion, we provide the first experimental evidence that collateral blood vessels at different cerebrovascular hierarchy are endogenously compensatory mechanisms in brain ischemia. © 2016 International Society of

Development of a computerized portal verification scheme for pelvic treatment fields

International Nuclear Information System (INIS)

Nie, K.; Yin, F.-F.; Gao, Q.; Brasacchio, R.

1996-01-01

Purpose/Objective: At present, treatment verification between portal and reference images is performed based on manually-identified features by radiation oncologist, which is both time-consuming and potentially error-prone. There is a demand for the computerized verification procedure in clinical application. The purpose of this study is to develop a computerized portal verification scheme for pelvic treatment fields. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature matching between reference and portal images and quantitative evaluation of patient setup. Electronic portal images with a matrix size of 256 x 256 and 12 bit gray levels were acquired using a liquid matrix electronic portal imaging device. Simulation images were acquired by digitizing simulation films using a TV camera into images with 256 x 256 matrix and 8 bit gray levels. Initially a Canny edge detector is applied to identify the field edges and an elliptic Fourier transformation is used to correlate the size and shape information between the reference and portal field edges. Several measures can be calculated using the transformation coefficients to describe the field shape, size and orientation. The quantitative information regarding to the relative shifts, rotation and magnification factor between portal and reference field edges can then be determined based on these measures. Next the pelvic brim, which is typically used as the landmark for radiation treatment verification, is identified by a pyramid searching process with double snakes defined from initial global area to final local area. A snake is an active model and energy-minimizing spline guided by external constraint forces and influenced by image forces that pull it toward features such as lines and edges. The search range is limited to the region between two snakes. Sobel edge detector and wavelet transformation approach are used to generate a serial image forces at

Fundamental factors influencing portal image quality

International Nuclear Information System (INIS)

Jaffray, D.A.

1995-01-01

It has been recognized that improved methods of verifying radiation field placement in external beam radiotherapy are required in order to make frequent checks of field placement feasible. As a result, a large number of electronic portal imaging systems have been developed as possible replacements for film. These developments have produced digital systems with faster acquisition and improved display contrast, however, the quality of the images acquired with such systems is still disappointing. This presentation examines many of the fundamental factors which limit the quality of radiographs obtained with a megavoltage radiotherapy beam. The size and shape of the radiation sources (focal and extra-focal) in radiotherapy machines and their influence on the spatial resolution of portal images are examined. Monte Carlo simulations of x-ray interactions within the patient determined that a significant fraction of the x-ray scatter generated in the patient is due to bremsstrahlung and positron annihilation. Depending on the detector, the scatter signal can reduce the differential signal-to-noise by 20%. Furthermore, a Monte Carlo study of the interaction of x-rays within typical fluoroscopic imaging detectors (metal plate/phosphor screen) demonstrates the degrading effect of energy absorption noise on the detective quantum efficiency of fluoroscopic based imaging systems. Finally, the spatial frequency content in the x-ray shadowgram is demonstrated to change with x-ray energy, resulting in images that appear to have reduced spatial resolution at megavoltage energies. The relative magnitude of each of these factors will be presented and recommendations for the next generation of portal imaging systems will be made

Noncirrotisk intrahepatisk portal hypertension

DEFF Research Database (Denmark)

Dam Fialla, Annette; Havelund, Troels

2007-01-01

Non-cirrhotic intrahepatic portal hypertension is characterized by portal hypertension in the absence of liver cirrhosis or portal vein thrombosis. The disease is common in the East and rarely seen in the West. Two cases with oesophageal varices are described. The histopathology is heterogeneous...... but includes vascular lesions and portal fibrosis. Patient management follows the current recommendations for variceal bleeding....

The medial collateral ligament of the elbow joint

DEFF Research Database (Denmark)

Floris, S; Olsen, Bo Sanderhoff; Dalstra, Michel

1998-01-01

Eighteen osteoligamentous elbow joint specimens were included in a study of the medial collateral ligament complex (MCL). The morphologic characteristics of the MCL were examined, and three-dimensional kinematic measurements were taken after selective ligament dissections were performed. On morph......Eighteen osteoligamentous elbow joint specimens were included in a study of the medial collateral ligament complex (MCL). The morphologic characteristics of the MCL were examined, and three-dimensional kinematic measurements were taken after selective ligament dissections were performed...

Effective collateral circulation may indicate improved perfusion territory restoration after carotid endarterectomy.

Science.gov (United States)

Lin, Tianye; Lai, Zhichao; Lv, Yuelei; Qu, Jianxun; Zuo, Zhentao; You, Hui; Wu, Bing; Hou, Bo; Liu, Changwei; Feng, Feng

2018-02-01

To investigate the relationship between the level of collateral circulation and perfusion territory normalisation after carotid endarterectomy (CEA). This study enrolled 22 patients with severe carotid stenosis that underwent CEA and 54 volunteers without significant carotid stenosis. All patients were scanned with ASL and t-ASL within 1 month before and 1 week after CEA. Collateral circulation was assessed on preoperative ASL images based on the presence of ATA. The postoperative flow territories were considered as back to normal if they conformed to the perfusion territory map in a healthy population. Neuropsychological tests were performed on patients before and within 7 days after surgery. ATA-based collateral score assessed on preoperative ASL was significantly higher in the flow territory normalisation group (n=11, 50 %) after CEA (P mean differences+2SD among control (MMSE=1.35, MOCA=1.02)]. This study demonstrated that effective collateral flow in carotid stenosis patients was associated with normalisation of t-ASL perfusion territory after CEA. The perfusion territory normalisation group tends to have more cognitive improvement after CEA. • Evaluation of collaterals before CEA is helpful for avoiding ischaemia during clamping. • There was good agreement on ATA-based ASL collateral grading. • Perfusion territories in carotid stenosis patients are altered. • Patients have better collateral circulation with perfusion territory back to normal. • MMSE and MOCA test scores improved more in the territory normalisation group.

De-novo collateral formation following acute myocardial infarction: Dependence on CCR2⁺ bone marrow cells.

Science.gov (United States)

Zhang, Hua; Faber, James E

2015-10-01

Wide variation exists in the extent (number and diameter) of native pre-existing collaterals in tissues of different strains of mice, with supportive indirect evidence recently appearing for humans. This variation is a major determinant of the wide variation in severity of tissue injury in occlusive vascular disease. Whether such genetic-dependent variation also exists in the heart is unknown because no model exists for study of mouse coronary collaterals. Also owing to methodological limitations, it is not known if ischemia can induce new coronary collaterals to form ("neo-collaterals") versus remodeling of pre-existing ones. The present study sought to develop a model to study coronary collaterals in mice, determine whether neo-collateral formation occurs, and investigate the responsible mechanisms. Four strains with known rank-ordered differences in collateral extent in brain and skeletal muscle were studied: C57BLKS>C57BL/6>A/J>BALB/c. Unexpectedly, these and 5 additional strains lacked native coronary collaterals. However after ligation, neo-collaterals formed rapidly within 1-to-2 days, reaching their maximum extent in ≤7 days. Rank-order for neo-collateral formation differed from the above: C57BL/6>BALB/c>C57BLKS>A/J. Collateral network conductance, infarct volume(-1), and contractile function followed this same rank-order. Neo-collateral formation and collateral conductance were reduced and infarct volume increased in MCP1(-/-) and CCR2(-/-) mice. Bone-marrow transplant rescued collateral formation in CCR2(-/-) mice. Involvement of fractalkine➔CX3CR1 signaling and endothelial cell proliferation were also identified. This study introduces a model for investigating the coronary collateral circulation in mice, demonstrates that neo-collaterals form rapidly after coronary occlusion, and finds that MCP➔CCR2-mediated recruitment of myeloid cells is required for this process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Collateralized debt obligations (CDOs

Directory of Open Access Journals (Sweden)

Dragosavac Miloš

2012-01-01

Full Text Available Collateralized debt obligations (CDOs were issued in 1987 by bankers at Drexel Burnham Lambert Inc. A decade later, CDOs became the leading power on the credit derivative markets, on which the value of derivative assets was derived from the value of other assets. However, unlike options and credit swamps, CDOs are not real, which means that they are constructed, and sometimes even the construction of their construction. CDOs were made to satisfy different types of investors, at one end, there is low-risk with low-income, and at the other, high-risk with high-income. By 2007, following the bubble burst on the US real estate market, losses on the CDO market started to expand. By 2008, the crisis on the CDO market turned into what we call today 'the global financial crisis.' CDOs are 'in the heart' of the crisis, and even wider. Our attempt is to reveal the mechanism of collateralized debt obligations (CDOs and the way in which CDOs expanded the negative effects of the present global financial crisis.

75 FR 64710 - Public Roundtable on Individual Customer Collateral Protection

Science.gov (United States)

2010-10-20

... related to individual customer collateral protection in the context of the CFTC's rulemaking efforts... customer collateral protection in the context of the Act, may do so via: paper submission to David Stawick... be in English or be accompanied by an English translation. All submissions provided to the CFTC in...

46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Collateral deposit fund, letter of transmittal, Form MA... Collateral deposit fund, letter of transmittal, Form MA-302. The standard form of letter of transmittal for use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency or...

Mobile Portal Implementation Strategy

DEFF Research Database (Denmark)

Gao, Ping; Damsgaard, Jan

2005-01-01

Mobile portal plays an important role in mobile commerce market. Current literature focuses on static analysis on the value chain of mobile portals. This article provides a dynamic perspective on mobile portal strategy. Drawing upon network economics, we describe mobile portal implementation...... as a fourphase process. In different phase, a portal provider has various challenges to overcome and adopt diverse strategies, and correspondingly the regulator has different foci. The conceptual framework proposed in this article offers a basis for further analyses on the market dynamics of mobile commerce......, and can be generalized to studying other networked technologies...

Monocytic microRNA profile associated with coronary collateral artery function in chronic total occlusion patients.

Science.gov (United States)

Hakimzadeh, Nazanin; Elias, Joëlle; Wijntjens, Gilbert W M; Theunissen, Ruud; van Weert, Angela; Smulders, Martijn W; van den Akker, Nynke; Moerland, Perry D; Verberne, Hein J; Hoebers, Loes P; Henriques, Jose P S; van der Laan, Anja M; Ilhan, Mustafa; Post, Mark; Bekkers, Sebastiaan C A M; Piek, Jan J

2017-05-08

An expansive collateral artery network is correlated with improved survival in case of adverse cardiac episodes. We aimed to identify cellular microRNAs (miRNA; miR) important for collateral artery growth. Chronic total occlusion (CTO) patients (n = 26) were dichotomized using pressure-derived collateral flow index (CFI p ) measurements; high collateral capacity (CFI p  > 0.39; n = 14) and low collateral (CFI p  collateral capacity patients. Validation by real-time polymerase chain reaction demonstrated significantly decreased expression of miR339-5p in all stimulated monocyte phenotypes of low collateral capacity patients. MiR339-5p showed significant correlation with CFI p values in stimulated monocytes. Ingenuity pathway analysis of predicted gene targets of miR339-5p and differential gene expression data from high versus low CFI p patients (n = 20), revealed significant association with STAT3 pathway, and also suggested a possible regulatory role for this signaling pathway. These results identify a novel association between miR339-5p and coronary collateral function. Future work examining modulation of miR339-5p and downstream effects on the STAT3 pathway and subsequent collateral vessel growth are warranted.

Roadside Tracker Portal-less Portal Monitor

Energy Technology Data Exchange (ETDEWEB)

Ziock, Klaus-Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cheriyadat, Anil M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bradley, Eric Craig [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cunningham, Mark F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fabris, Lorenzo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goddard, Jr, James Samuel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hornback, Donald Eric [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Karnowski, Thomas Paul [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kerekes, Ryan A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Newby, Jason [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2013-07-01

This report documents the full development cycle of the Roadside Tracker (RST) Portal-less Portal monitor (Fig. 1) funded by DHS DNDO. The project started with development of a proof-of-feasibility proto-type, proceeded through design and construction of a proof-of-concept (POC) prototype, a test-and-evaluation phase, participation in a Limited Use Exercise that included the Standoff Radiation Detections Systems developed under an Advanced Technology Demonstration and concluded with participation in a Characterization Study conducted by DNDO.

Determinants of leptomeningeal collateral flow in stroke patients with a middle cerebral artery occlusion

NARCIS (Netherlands)

van Seeters, Tom; Biessels, Geert Jan; Kappelle, L. Jaap; van der Graaf, Yolanda; Velthuis, Birgitta K.

2016-01-01

INTRODUCTION: Poor leptomeningeal collateral flow is related to worse clinical outcome in acute ischemic stroke, but the factors that determine leptomeningeal collateral patency are largely unknown. We explored the determinants of leptomeningeal collateral flow and assessed their effect on the

Radiology of liver circulation

International Nuclear Information System (INIS)

Hermine, C.L.

1985-01-01

This book proposes that careful evaluation of the arterioportogram is the cornerstone in assessing portal flow obstruction, being the most consistent of all observations including liver histology, portal venous pressure, size and number of portosystemic collaterals, and wedged hepatic venous pressure. Very brief chapters cover normal hepatic circulation and angiographic methods. Contrast volumes and flow rates for celiac, hepatic, and superior mesenteric injection are given, with the timing for venous phase radiographs. In the main body of the text, portal obstruction is divided very simply into presinusoidal (all proximal causes) and postsinusoidal (all distal causes, including Budd-Chiari). Changes are discussed regarding the splenic artery and spleen; hepatic artery and its branches; portal flow rate and direction; and arterioportal shunting and portosystemic collateral circulation in minimal, moderate, severe, and very severe portal obstruction and in recognizable entities such as prehepatic portal and hepatic venous obstructions. The major emphasis in this section is the recognition and understanding of flow changes by which level and severity of obstruction are assessed (not simply the anatomy of portosystemic collateral venous flow). Excellent final chapters discuss the question of portal hypertension without obstruction, and the contribution of arterioportography to the treatment of portal hypertension, again with an emphasis on hemodynamics before and after shunt surgery. There is a fascinating final chapter on segmental intrahepatic obstruction without portal hypertension that explains much of the unusual contrast enhancement sometimes seen in CT scanning of hepatic mass lesions

12 CFR 725.19 - Collateral requirements.

Science.gov (United States)

2010-01-01

... CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.19 Collateral requirements. (a) Each... applicable Facility advance or Agent loan, or by guarantee of the National Credit Union Share Insurance Fund...

Sonographic findings in the Cruveilhier-von Baumgarten syndrome

International Nuclear Information System (INIS)

Pirschel, J.

1982-01-01

Portal hypertension is the most common complication of cirrhosis of the liver and leads to a reversal of blood flow and re-opening of pre-formed portal-systemic collaterals. Amongst a variety of possible hepato-fugal collaterals, the Cruveilhier-von Baumgarten syndrome, consisting of the reopening of umbilical veins, is a rare variant. It has been possible to demonstrate this clearly by sonography in 18 patients. (orig.) [de

13 CFR 123.513 - Does SBA require collateral on its Military Reservist EIDL?

Science.gov (United States)

2010-01-01

..., or both. SBA will not decline a loan if you do not have a particular amount of collateral so long as SBA is reasonably sure that you can repay the loan. If you refuse to pledge the available collateral... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Does SBA require collateral on its...

Determining the optimal portal blood volume in a shunt before surgery in extrahepatic portal hypertension

Directory of Open Access Journals (Sweden)

Yurchuk Vladimir A

2016-04-01

Full Text Available The aim of the study: To determine the necessary shunt diameter and assess the optimal portal blood volume in a shunt in children with extrahepatic portal hypertension before the portosystemic shunt surgery. Changes in the liver hemodynamics were studied in 81 children aged from 4 to 7 years with extrahepatic portal hypertension. We established that it is necessary to calculate the shunt diameter and the blood volume in a shunt in patients with extrahepatic portal hypertension before the portosystemic shunt surgery. It allows us to preserve the hepatic portal blood flow and effectively decrease the pressure in the portal system. Portosystemic shunt surgery in patients with extrahepatic portal hypertension performed in accordance with the individualized shunt volume significantly decreases portal pressure, preserves stable hepatic hemodynamics and prevents gastro-esophageal hemorrhage.

CT findings of portal vein aneurysm

International Nuclear Information System (INIS)

Yang, Dal Mo; Chang, Mi Son; Yoon, Myung Hwan; Kim, Hak Soo; Kim, Hyung Sik; Chung, Hyo Sun; Chung, Jin Woo

1999-01-01

To describe the CT findings of portal vein aneurysm in eight patients. All patients included in this study (two men and six women) underwent CT examinations between October 1996 and June1998. Of these eight, three were suffering from hepatic disease and portal hypertension. We determined the location, shape, size, and characteristics of the lesions, and the presence or absence of portal vein anomaly. Seven patients had intrahepatic portal vein aneurysm (at the umbilical portion of the left portal vein in five patients, between the transverse and umbilical portion of the left portal vein in one, and at the bifurcation of the anterior and posterior branch of the right portal vein in one), while extrahepatic portal vein aneurysm, at the confluence of the superior mesenteric and splenic vein was found in only one. Lesions were cyst-shaped in seven cases and saccular in one, and showed well-circumscribed, markedly enhanced mass, which communicated with the portal vein and/or gives off major branches. Portal vein anomaly, in which the right anterior segmental portal vein originated from the umbilical portion of the left portal vein, was seen in three patients. In all three, intrahepatic portal vein aneurysm was present at the umbilical portion of the left portal vein, and in one, the umbilical protion of the left portal vein was located to the right of the Cantlic line. CT examination can help reveal portal vein aneurysm by detecting a well-circumscribed, markedly enhanced mass which communicates with the portal vein and/or gives off major branches

Pediatric portal hypertension

Science.gov (United States)

Vogel, Clarissa Barbon

2017-01-01

Abstract: Pediatric portal hypertension management is a team approach between the patient, the patient's family, the primary caregiver, and specialty providers. Evidence-based practice guidelines have not been established in pediatrics. This article serves as a review for the primary care NP in the management of pediatric portal hypertension, discussing the etiology, pathophysiology, and clinical presentation of pediatric portal hypertension, diagnostic tests, and treatment and management options. PMID:28406835

Assessment of the significance of coronary collateral vessel by using thallium-201 myocardial imaging

International Nuclear Information System (INIS)

Kanoh, Yasushi; Shiotani, Hideyuki; Fukuzaki, Hisashi; Maeda, Kazumi.

1988-01-01

For functional assessment of coronary collateral vessels, twenty-three patients with effort angina pectoris who had total coronary obstruction were studied. The patients were divided depending on the degree of development of collateral vessels into two groups, i.e. good collateral group I (n = 13) and poor collateral group II (n = 10). Thallium-201 scan was performed immediately (Ex-1 image), 20 minutes (Ex-2 image) after exercise and after nitroglycerin administration (NTG image) respectively. In all images, the relative percent activity of thallium-201 in the collateral-dependent ischemic area to the normal myocardium were calculated and were compaired between two groups. Relative percent activities in group I and II were as follows : Ex-1 image ; 75.8 ± 3.5 % vs. 77.2 ± 2.9 % (NS), Ex-2 images ; 85.3 ± 4.5 % vs. 79.3 ± 3.9 % (p < 0.005), NTG image ; 97.3 ± 3.1 % vs. 96.4 ± 5.2 % (NS). From these results, it was elucidated that good collateral induced early partial redistribution in its perfusion area, suggesting that good collateral circulation may provide rapid recovery from myocardial ischemia. (author)

Measuring the collateral network pressure to minimize paraplegia risk in thoracoabdominal aneurysm resection.

Science.gov (United States)

Etz, Christian D; Zoli, Stefano; Bischoff, Moritz S; Bodian, Carol; Di Luozzo, Gabriele; Griepp, Randall B

2010-12-01

To minimize paraplegia during thoracoabdominal aortic aneurysm repair, the concept of the collateral network was developed. That is, spinal cord perfusion is provided by an interconnecting complex of vessels in the intraspinal, paraspinous, and epidural space and in the paravertebral muscles, including intercostal and lumbar segmental as well as subclavian and hypogastric arteries. Collateral network pressure was measured with a catheter in the distal end of a ligated segmental artery in pigs and human beings. In the pig, collateral network pressure was 75% of the simultaneous mean aortic pressure. With complete segmental arterial ligation, it fell to 27% of baseline, recovering to 40% at 24 hours and 90% at 120 hours. Spinal cord injury occurred in approximately 50% of animals. When all segmental arteries were taken in 2 stages a week apart, collateral network pressure fell only to 50% to 70% of baseline, and spinal cord injury was rare. In human beings, baseline collateral network pressure also was 75% of mean aortic pressure, fell in proportion to the number of segmental arteries ligated, and began recovery within 24 hours. Collateral network pressure was lower with nonpulsatile distal bypass than with pulsatile perfusion. After subtraction of a measure of spinal cord outflow pressure (cerebrospinal fluid pressure or central venous pressure), collateral network pressure provides a clinically useful estimate of spinal cord perfusion pressure. Copyright © 2010. Published by Mosby, Inc.

Predicting Collateral Status With Magnetic Resonance Perfusion Parameters: Probabilistic Approach With a Tmax-Derived Prediction Model.

Science.gov (United States)

Lee, Mi Ji; Son, Jeong Pyo; Kim, Suk Jae; Ryoo, Sookyung; Woo, Sook-Young; Cha, Jihoon; Kim, Gyeong-Moon; Chung, Chin-Sang; Lee, Kwang Ho; Bang, Oh Young

2015-10-01

Good collateral flow is an important predictor for favorable responses to recanalization therapy and successful outcomes after acute ischemic stroke. Magnetic resonance perfusion-weighted imaging (MRP) is widely used in patients with stroke. However, it is unclear whether the perfusion parameters and thresholds would predict collateral status. The present study evaluated the relationship between hypoperfusion severity and collateral status to develop a predictive model for good collaterals using MRP parameters. Patients who were eligible for recanalization therapy that underwent both serial diffusion-weighted imaging and serial MRP were enrolled into the study. A collateral flow map derived from MRP source data was generated through automatic postprocessing. Hypoperfusion severity, presented as proportions of every 2-s Tmax strata to the entire hypoperfusion volume (Tmax≥2 s), was compared between patients with good and poor collaterals. Prediction models for good collaterals were developed with each Tmax strata proportion and cerebral blood volumes. Among 66 patients, 53 showed good collaterals based on MRP-based collateral grading. Although no difference was noted in delays within 16 s, more severe Tmax delays (Tmax16-18 s, Tmax18-22 s, Tmax22-24 s, and Tmax>24 s) were associated with poor collaterals. The probability equation model using Tmax strata proportion demonstrated high predictive power in a receiver operating characteristic analysis (area under the curve=0.9303; 95% confidence interval, 0.8682-0.9924). The probability score was negatively correlated with the volume of infarct growth (P=0.030). Collateral status is associated with more severe Tmax delays than previously defined. The present Tmax severity-weighted model can determine good collaterals and subsequent infarct growth. © 2015 American Heart Association, Inc.

COLLATERAL IN SMES’ LENDING: BANKS’ REQUIREMENTS VS CUSTOMERS’ EXPECTATIONS

OpenAIRE

Daniel BADULESCU

2011-01-01

SMEs’ support and importance in developing economies should not be only declarative. Searching for funding, managers encounter various obstacles arising from information asymmetry, lack of experience, severe market conditions, and insufficient or unsatisfactory collaterals for banks (OECD 2006; Badulescu and Badulescu 2010; OECD 2000 and 2004; Lin and Sun 2006; Toivanen and Cresy, 2000). The collateral issue is extensively discussed in literature – preventing moral hazard, the alignment the i...

In vivo metacarpophalanageal joint collateral ligament length changes during flexion.

Science.gov (United States)

Sun, Y C; Sheng, X M; Chen, J; Qian, Z W

2017-07-01

We investigated the in vivo length changes of the collateral ligaments of metacarpophalangeal joint during flexion. We obtained computed tomography scans of index, middle, ring and little fingers at 0°, 30°, 60° and 90° of joint flexion from six hands of six healthy adult volunteers. Three of them had their dominant right hand studied, and the other three had their non-dominant left hand studied. We measured and analysed the radial and ulnar collateral ligaments of each metacarpophalangeal joint from the reconstructed images. We found that the dorsal and middle portions of the both radial and ulnar collateral ligament lengthened progressively during digital flexion and reached the maximum at 90° flexion. The length of the volar portion increased from 0° to 30° flexion and then decreased from 30° to 60° flexion, reaching the minimum at 90°. In conclusion, three portions of collateral ligaments on both sides of the metacarpophalangeal joint have variable length changes during flexion, which act to stabilize the joint through its flexion arc.

Redistribution of thallium-201 into right ventricle through collateral circulation

International Nuclear Information System (INIS)

Kataoka, Hajime; Ohkubo, Toshitaka; Takaoka, Shigeru; Ohshige, Tamao; Miyahara, Kenkichi.

1984-01-01

The cases of reversible right ventricular ischemia, which demonstrated redistribution of thallium (Tl)-201 into the right ventricular free wall (RVFW) through collateral channels, were reported. Two cases with complete obstruction in the proximal right coronary artery accompanied by collateral channels (left coronary artery to distal right coronary artery) underwent submaximal exercise stress Tl-201 myocardial imaging. Although the RVFW was not visualized on immediate myocardial images in one or both of the 30 0 and 60 0 left anterior oblique views in each case, three-hour delayed myocardial images showed redistribution of Tl-201 into the RVFW. It was concluded that collateral circulation affects the occurrence of redistribution of Tl-201 into the RVFW. (author)

Treatment of hepatic neoplasm through extrahepatic collaterals

Energy Technology Data Exchange (ETDEWEB)

Soo, C.S.; Chuang, V.P.; Wallace, S.; Charnsangavej, C.; Carrasco, H.

1983-04-01

Twenty-nine patients with hepatic artery occlusion were treated with additional hepatic infusion or embolization through extrahepatic collaterals. Seventeen courses of hepatic infusion were performed in 13 patients through the inferior pancreaticoduodenal artery, left gastric artery, or right gastric artery. Twenty-five hepatic embolization procedures were performed in 16 patients through the right and left phrenic arteries, left and right gastric arteries, pancreaticoduodenal artery, gastroduodenal artery, or omentoepiploic artery. In one patient gastric ulcers developed following left gastric artery infusion. No complication related to the embolization procedure was observed in the embolization group. The extrahepatic collaterals are important alternative routes for continuous transcatheter management of hepatic neoplasms following hepatic artery occlusion.

Treatment of hepatic neoplasm through extrahepatic collaterals

International Nuclear Information System (INIS)

Soo, C.S.; Chuang, V.P.; Wallace, S.; Charnsangavej, C.; Carrasco, H.

1983-01-01

Twenty-nine patients with hepatic artery occlusion were treated with additional hepatic infusion or embolization through extrahepatic collaterals. Seventeen courses of hepatic infusion were performed in 13 patients through the inferior pancreaticoduodenal artery, left gastric artery, or right gastric artery. Twenty-five hepatic embolization procedures were performed in 16 patients through the right and left phrenic arteries, left and right gastric arteries, pancreaticoduodenal artery, gastroduodenal artery, or omentoepiploic artery. In one patient gastric ulcers developed following left gastric artery infusion. No complication related to the embolization procedure was observed in the embolization group. The extrahepatic collaterals are important alternative routes for continuous transcatheter management of hepatic neoplasms following hepatic artery occlusion

A novel flow-based parameter of collateral function assessed by intracoronary thermodilution.

Science.gov (United States)

Lindner, Markus; Felix, Stephan B; Empen, Klaus; Reffelmann, Thorsten

2014-04-01

Currently, many methods for quantitation of coronary collateral function are based on intracoronary pressure measurements distal of an occluded balloon, which do not fully account for the dynamic nature of collateral flow. Therefore, a flow-based parameter of coronary collateral function based upon principles of thermodilution was evaluated. In 26 patients with a high-grade coronary artery stenosis, intracoronary hemodynamics were analyzed by the RadiAnalyzer system (St Jude Medical), including fractional flow reserve (FFR), index of microcirculatory resistance (IMR), and the pressure-based collateral flow index (CFI) during balloon occlusion and hyperemia (intravenous adenosine). Moreover, immediately after an intracoronary bolus of room-temperature saline, the balloon was occluded and the intracoronary temperature distal to the balloon was analyzed over time. The slope of the temperature-time curve was calculated after logarithmic transformation as an index of collateral blood flow (CBFI). The coefficient of variation between two measurements of CBFI amounted to 11 ± 2%. In patients with CFI ≥0.25, CBFI amounted to 0.55 ± 0.09, whereas in those with CFI function, and should be evaluated in further studies.

A Case of Left Renal Vein Ligation in a Patient with Solitary Left Kidney Undergoing Liver Transplantation to Control Splenorenal Shunt and Improve Portal Venous Flow.

Science.gov (United States)

Martino, Rodrigo B; Júnior, Eserval Rocha; Manuel, Valdano; Rocha-Santos, Vinicius; D'Albuquerque, Luis Augusto C; Andraus, Wellington

2017-10-11

BACKGROUND Adequate portal venous flow is required for successful liver transplantation. Reduced venous flow and blood flow 'steal' by collateral vessels are a concern, and when there is a prominent splenorenal shunt present, ligation of the left renal vein has been recommended to improve portal venous blood flow. CASE REPORT A 51-year-old man who had undergone right nephrectomy in childhood required liver transplantation for liver cirrhosis and hepatocellular carcinoma due to hepatitis C virus (HCV) infection. The patient had no other comorbidity and no history of hepatorenal syndrome. At transplantation surgery, portal venous flow was poor and did not improve with ligation of shunt veins, but ligation of the left renal vein improved portal venous flow. On the first and fifth postoperative days, the patient was treated with basiliximab, a chimeric monoclonal antibody to the IL-2 receptor, and methylprednisolone. The calcineurin inhibitor, tacrolimus, was introduced on the fifth postoperative day. On the sixteenth postoperative day, renal color Doppler ultrasound showed normal left renal parenchyma; hepatic Doppler ultrasound showed good portal vein flow and preserved hepatic parenchyma in the liver transplant. CONCLUSIONS This case report has shown that in a patient with a single left kidney, left renal vein ligation is feasible and safe in a patient with no other risk factors for renal impairment following liver transplantation. Modification of postoperative immunosuppression to avoid calcineurin inhibitors in the very early postoperative phase may be important in promoting good recovery of renal function and to avoid the need for postoperative renal dialysis.

Decreased perfusion in myocardial region of normal donor artery secondary to collateral development

International Nuclear Information System (INIS)

Koga, Y.; Takahashi, M.; Kojima, A.; Takaki, Y.; Tomiguchi, S.; Hirota, Y.; Kugiyama, K.; Yasue, H.; Hayasaki, K.; Kumamoto Saiseikai Hospital

1992-01-01

Thirty-one patients suffering from single vessel exertional angina with collaterals (Group A) were evaluated by stress 201 Tl myocardial emission CT (Tl-SPECT) with 16 controls of severely stenotic single vessel exertional angina without collaterals (Group B). Group A included 21 patients (68%) who showed an extensive perfusion defect in double artery myocardial regions, including the normal donor artery myocardial region (DMR). However, there were no such cases in Group B, giving a significant difference between these 2 groups (p < 0.001). Four patients in Group A, having a perfusion defect both in DMR and in the collateral dependent myocardial region (CMR) underwent a successful percutaneous transluminal coronary angioplasty (PTCA) with disappearance of collaterals. Tl-SPECT findings after PTCA showed no perfusion defect either in CMR or in DMR. This has been explained on the basis that the coronary collaterals stole blood and produced perfusion defect in DMR. (orig.)

Collateral Consequences and Effectiveness of Sex Offender Registration and Notification: Law Enforcement Perspectives.

Science.gov (United States)

Cubellis, Michelle A; Walfield, Scott M; Harris, Andrew J

2018-03-01

A growing body of research has examined the collateral effects of sex offender registration and notification (SORN), particularly those related to offenders' social and economic reintegration into society. Although studies have examined public, offender, treatment provider, and other criminal justice perspectives on SORN's collateral impacts, few have elicited the views of law enforcement (LE) professionals who have contact with registered offenders. This study presents results from a mixed method study examining LE perspectives on collateral consequences and effectiveness of SORN. Results indicate that, although overall LE concern regarding collateral impacts is limited, those who are most engaged in SORN-related duties are significantly more likely to indicate such concern, and also more likely to believe that SORN was an effective public safety tool. Importantly, respondents in states with larger registries expressed greater concern over collateral consequences, and less belief in SORN's public safety efficacy. Implications for policy and practice are discussed.

Impact of Admission Blood Glucose on Coronary Collateral Flow in Patients with ST-Elevation Myocardial Infarction.

Science.gov (United States)

Kurmus, Ozge; Aslan, Turgay; Ekici, Berkay; Baglan Uzunget, Sezen; Karaarslan, Sukru; Tanindi, Asli; Erkan, Aycan Fahri; Akgul Ercan, Ebru; Kervancıoglu, Celal

2018-01-01

In patients with acute myocardial infarction, glucose metabolism is altered and acute hyperglycemia on admission is common regardless of diabetes status. The development of coronary collateral is heterogeneous among individuals with coronary artery disease. In this study, we aimed to investigate whether glucose value on admission is associated with collateral flow in ST-elevation myocardial infarction (STEMI) patients. We retrospectively evaluated 190 consecutive patients with a diagnosis of first STEMI within 12 hours of onset of chest pain. Coronary collateral development was graded according to Rentrop classification. Rentrop 0-1 was graded as poor collateral development, and Rentrop 2-3 was graded as good collateral development. Admission glucose was measured and compared between two groups. Mean admission glucose level was 173.0 ± 80.1 mg/dl in study population. Forty-five (23.7%) patients had good collateral development, and 145 (76.3%) patients had poor collateral development. There were no statistically significant differences in demographic characteristics between two groups. Three-vessel disease was more common in patients with good collateral development ( p =0.026). Mean admission glucose level was higher in patients with poor collateral than good collateral (180.6 ± 84.9 mg/dl versus 148.7 ± 56.6 mg/dl, resp., p =0.008). In univariate analysis, higher admission glucose was associated with poor collateral development, but multivariate logistic regression analysis revealed a borderline result (odds ratio 0.994, 95% CI 0.989-1.000, p =0.049). Our results suggest that elevated glucose on admission may have a role in the attenuation of coronary collateral blood flow in acute myocardial infarction. Further studies are needed to validate our results.

Índice de congestão portal e a ocorrência de trombose portal pós-dape Portal congestion and thrombosis after EDS

Directory of Open Access Journals (Sweden)

Fabio Gonçalves Ferreira

2005-08-01

Full Text Available OBJETIVO: Comparar os dados obtidos pela ultra-sonografia com doppler no pré-operatório de esquistossomóticos submetidos à desconexão ázigo-portal com esplenectomia (DAPE, calculando o índice de congestão portal, e sua correlação com a trombose portal no pós-operatório. MÉTODOS: Foram estudados 65 pacientes submetidos à DAPE por hipertensão portal esquistossomótica com antecedente de hemorragia digestiva, divididos em dois grupos: Grupo A (28 pacientes que não desenvolveram trombose portal pós-operatória e Grupo B (37 pacientes com trombose portal no pós-operatório. Analisaram-se através de ultra-sonografia com doppler no pré-operatório os seguintes parâmetros da veia porta: diâmetro, área, velocidade média de fluxo do sangue, fluxo de sangue, e estabeleceu-se o índice de congestão portal. RESULTADOS: O diâmetro, área e o fluxo da veia porta foram maiores no grupo B (média de 1,52 cm; 1,77 cm² e 2533,12 ml/min em relação ao grupo A (média de 1,33 cm; 1,44 cm² e 1609,03 ml/min com p = 0,03; 0,03 e 0,04 respectivamente. O índice de congestão portal não foi estatisticamente significativo na comparação dos dois grupos (p = 0,07. CONCLUSÃO: O índice de congestão portal obtido no pré-operatório através da ultra-sonografia com doppler não se mostrou preditivo de trombose portal no pós-operatório dos doentes estudados.BACKGROUND: The study compared the preoperative portal vein congestion index estimated by Doppler ultrasound and the postoperative portal vein thrombosis of patients submitted to esophagogastric devascularization and splenectomy (EDS. METHODS: 65 patients with portal hypertension due to schistosomiasis and previous gastrointestinal bleeding submitted to EDS were divided into two groups: GROUP A (28 patients without postoperative portal vein thrombosis and GROUP B (37 patients with postoperative portal vein thrombosis. The following parameters of preoperative Doppler ultrasound of the

Characterizing the angiogenic activity of patients with single ventricle physiology and aortopulmonary collateral vessels.

Science.gov (United States)

Sandeep, Nefthi; Uchida, Yutaka; Ratnayaka, Kanishka; McCarter, Robert; Hanumanthaiah, Sridhar; Bangoura, Aminata; Zhao, Zhen; Oliver-Danna, Jacqueline; Leatherbury, Linda; Kanter, Joshua; Mukouyama, Yoh-Suke

2016-04-01

Patients with single ventricle congenital heart disease often form aortopulmonary collateral vessels via an unclear mechanism. To gain insights into the pathogenesis of aortopulmonary collateral vessels, we correlated angiogenic factor levels with in vitro activity and angiographic aortopulmonary collateral assessment and examined whether patients with single ventricle physiology have increased angiogenic factors that can stimulate endothelial cell sprouting in vitro. In patients with single ventricle physiology (n = 27) and biventricular acyanotic control patients (n = 21), hypoxia-inducible angiogenic factor levels were measured in femoral venous and arterial plasma at cardiac catheterization. To assess plasma angiogenic activity, we used a 3-dimensional in vitro cell sprouting assay that recapitulates angiogenic sprouting. Aortopulmonary collateral angiograms were graded using a 4-point scale. Compared with controls, patients with single ventricle physiology had increased vascular endothelial growth factor (artery: 58.7 ± 1.2 pg/mL vs 35.3 ± 1.1 pg/mL, P collateral severity. We are the first to correlate plasma angiogenic factor levels with angiography and in vitro angiogenic activity in patients with single ventricle disease with aortopulmonary collaterals. Patients with single ventricle disease have increased stromal-derived factor 1-alpha and soluble fms-like tyrosine kinase-1, and their roles in aortopulmonary collateral formation require further investigation. Plasma factors and angiogenic activity correlate poorly with aortopulmonary collateral severity in patients with single ventricles, suggesting complex mechanisms of angiogenesis. Published by Elsevier Inc.

Prediction of infarction and reperfusion in stroke by flow- and volume-weighted collateral signal in MR angiography.

Science.gov (United States)

Ernst, M; Forkert, N D; Brehmer, L; Thomalla, G; Siemonsen, S; Fiehler, J; Kemmling, A

2015-02-01

In proximal anterior circulation occlusive strokes, collateral flow is essential for good outcome. Collateralized vessel intensity in TOF- and contrast-enhanced MRA is variable due to different acquisition methods. Our purpose was to quantify collateral supply by using flow-weighted signal in TOF-MRA and blood volume-weighted signal in contrast-enhanced MRA to determine each predictive contribution to tissue infarction and reperfusion. Consecutively (2009-2013), 44 stroke patients with acute proximal anterior circulation occlusion met the inclusion criteria with TOF- and contrast-enhanced MRA and penumbral imaging. Collateralized vessels in the ischemic hemisphere were assessed by TOF- and contrast-enhanced MRA using 2 methods: 1) visual 3-point collateral scoring, and 2) collateral signal quantification by an arterial atlas-based collateral index. Collateral measures were tested by receiver operating characteristic curve and logistic regression against 2 imaging end points of tissue-outcome: final infarct volume and percentage of penumbra saved. Visual collateral scores on contrast-enhanced MRA but not TOF were significantly higher in patients with good outcome. Visual collateral scoring on contrast-enhanced MRA was the best rater-based discriminator for final infarct volume 50% (area under the curve, 0.67; P = .04). Atlas-based collateral index of contrast-enhanced MRA was the overall best independent discriminator for final infarct volume of collateral index combining the signal of TOF- and contrast-enhanced MRA was the overall best discriminator for effective reperfusion (percentage of penumbra saved >50%; area under the curve, 0.89; P collateral assessment, TOF- and contrast-enhanced MRA both contain predictive signal information for penumbral reperfusion. This could improve risk stratification in further studies. © 2015 by American Journal of Neuroradiology.

Biology of portal hypertension.

Science.gov (United States)

McConnell, Matthew; Iwakiri, Yasuko

2018-02-01

Portal hypertension develops as a result of increased intrahepatic vascular resistance often caused by chronic liver disease that leads to structural distortion by fibrosis, microvascular thrombosis, dysfunction of liver sinusoidal endothelial cells (LSECs), and hepatic stellate cell (HSC) activation. While the basic mechanisms of LSEC and HSC dysregulation have been extensively studied, the role of microvascular thrombosis and platelet function in the pathogenesis of portal hypertension remains to be clearly characterized. As a secondary event, portal hypertension results in splanchnic and systemic arterial vasodilation, leading to the development of a hyperdynamic circulatory syndrome and subsequently to clinically devastating complications including gastroesophageal varices and variceal hemorrhage, hepatic encephalopathy from the formation of portosystemic shunts, ascites, and renal failure due to the hepatorenal syndrome. This review article discusses: (1) mechanisms of sinusoidal portal hypertension, focusing on HSC and LSEC biology, pathological angiogenesis, and the role of microvascular thrombosis and platelets, (2) the mesenteric vasculature in portal hypertension, and (3) future directions for vascular biology research in portal hypertension.

Extrahepatic portal hypertension in childhood

International Nuclear Information System (INIS)

Takehara, Hiroo; Komi, Nobuhiko; Goh, Masahiro; Yoshida, Sadahiro; Kameoka, Kazuhiro; Hino, Masao; Sui, Osamu

1986-01-01

Four pediatric patients with extrahepatic portal hypertension had undergone portography and computerized radionuclide angiography in order to examine shape of portal system and to evaluate hepatic blood flow before and aftersurgical treatment. In all patients, cavernous transformation of portal system was demonstrated by portography, and in one of them spontaneous splenorenal shunt occurred. In 3 of them, who underwent esophageal transsection combined with paraesophagogastric devascularization and splenectomy, so-called direct operation, increase of portal blood flow was revealed by computerized radionuclide angiography. It is suggested that direct operation increasing portal blood flow after surgery is effective in treating extrahepatic portal hypertension in childhood. (author)

Cardiovascular risk factors cause premature rarefaction of the collateral circulation and greater ischemic tissue injury.

Science.gov (United States)

Moore, Scott M; Zhang, Hua; Maeda, Nobuyo; Doerschuk, Claire M; Faber, James E

2015-07-01

Collaterals lessen tissue injury in occlusive disease. However, aging causes progressive decline in their number and smaller diameters in those that remain (collateral rarefaction), beginning at 16 months of age in mice (i.e., middle age), and worse ischemic injury-effects that are accelerated in even 3-month-old eNOS(-/-) mice. These findings have found indirect support in recent human studies. We sought to determine whether other cardiovascular risk factors (CVRFs) associated with endothelial dysfunction cause collateral rarefaction, investigate possible mechanisms, and test strategies for prevention. Mice with nine different models of CVRFs of 4-12 months of age were assessed for number and diameter of native collaterals in skeletal muscle and brain and for collateral-dependent perfusion and ischemic injury after arterial occlusion. Hypertension caused collateral rarefaction whose severity increased with duration and level of hypertension, accompanied by greater hindlimb ischemia and cerebral infarct volume. Chronic treatment of wild-type mice with L-N (G)-nitro-arginine methylester caused similar rarefaction and worse ischemic injury which were not prevented by lowering arterial pressure with hydralazine. Metabolic syndrome, hypercholesterolemia, diabetes mellitus, and obesity also caused collateral rarefaction. Neither chronic statin treatment nor exercise training lessened hypertension-induced rarefaction. Chronic CVRF presence caused collateral rarefaction and worse ischemic injury, even at relatively young ages. Rarefaction was associated with increased proliferation rate of collateral endothelial cells, effects that may promote accelerated endothelial cell senescence.

Functional significance of coronary collateral circulation during dynamic exercise evaluated by thallium-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Wainwright, R.J.; Maisey, M.N.; Edwards, A.C.; Sowton, E.

1980-01-01

Sixty-five patients with angiographically documented coronary artery disease were investigated by thallium-201 ( 201 Tl) scintigraphy to determine the role of the collateral circulation during dynamic exercise. Fifty-three patients had complete proximal occlusion of at least one major coronary artery. One patient had total occlusion of all three major coronary arteries. Sixty-four collateral channels were identified, graded, and compared with corresponding regions of the myocardial scintigram. Tracer uptake was also graded and classified as various degrees of protection from ischaemia. A significant correlation between good collaterals with complete protection and poor or absent collaterals with no protection was noted. Seventeen patients (20 occluded vessels) had total coronary occlusion without myocardial infarction. Collaterals conferred protection in 9/15 occlusions whereas no protection was seen in five occlusions without collaterals. There was no difference in the protective role of homocoronary and heterocoronary collateral vessels. Hypertrophy of the first septal left anterior descending perforator conferred significant protection from ischaemia in contrast to bridging collaterals and ghosting. During exercise the right coronary bed is preferentially protected from ischaemia, in contrast to the left anterior descending territory. This probably reflects the direction of a transmural flow gradient between left and right ventricles during exercise. (author)

Collateral findings during computed tomography scan for atrial fibrillation ablation: Let's take a look around.

Science.gov (United States)

Perna, Francesco; Casella, Michela; Narducci, Maria Lucia; Dello Russo, Antonio; Bencardino, Gianluigi; Pontone, Gianluca; Pelargonio, Gemma; Andreini, Daniele; Vitulano, Nicola; Pizzamiglio, Francesca; Conte, Edoardo; Crea, Filippo; Tondo, Claudio

2016-04-26

The growing number of atrial fibrillation catheter ablation procedures warranted the development of advanced cardiac mapping techniques, such as image integration between electroanatomical map and cardiac computed tomography. While scanning the chest before catheter ablation, it is frequent to detect cardiac and extracardiac collateral findings. Most collateral findings are promptly recognized as benign and do not require further attention. However, sometimes clinically relevant collateral findings are detected, which often warrant extra diagnostic examinations or even invasive procedure, and sometimes need to be followed-up over time. Even though reporting and further investigating collateral findings has not shown a clear survival benefit, almost all the working groups providing data on collateral findings reported some collateral findings eventually coming out to be malignancies, sometimes at an early stage. Therefore, there is currently no clear agreement about the right strategy to be followed.

Usability of Discovery Portals

NARCIS (Netherlands)

Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.

2013-01-01

As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals

Clinical, angiographic and hemodynamic predictors of recruitable collateral flow assessed during balloon angioplasty coronary occlusion

NARCIS (Netherlands)

Piek, J. J.; van Liebergen, R. A.; Koch, K. T.; Peters, R. J.; David, G. K.

1997-01-01

We sought to determine the predictive value of factors influencing coronary collateral vascular responses in humans. There is limited information on the factors responsible for coronary collateral vascular development, despite the protective effect of collateral vessels in ischemic syndromes.

12 CFR 221.7 - Supplement: Maximum loan value of margin stock and other collateral.

Science.gov (United States)

2010-01-01

... value of margin stock and other collateral. (a) Maximum loan value of margin stock. The maximum loan... nonmargin stock and all other collateral. The maximum loan value of nonmargin stock and all other collateral... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Supplement: Maximum loan value of margin stock...

Collateralization, Bank Loan Rates and Monitoring : Evidence from a Natural Experiment

NARCIS (Netherlands)

Cerqueiro, G.M.; Ongena, S.; Roszbach, K.

2011-01-01

Collateral is one of the most important features of a debt contract. A substantial theoretical literature motivates the use of collateral as a means to alleviate ex-ante and ex-post information asymmetries between borrowers and lenders and the incidence of credit rationing. Through its seniority

Association between portal vein pressure drop gradient after transjugular intrahepatic portosystemic shunt and clinical prognosis

Directory of Open Access Journals (Sweden)

XU Zhengguo

2016-12-01

.e., a 36%-40% reduction in portal vein pressure. The results of splenic venography performed immediately after surgery showed that varicose veins almost disappeared and that there were no collateral varices. Gastroscopy was performed again within 1 month after surgery and 5 patients had no significant changes in esophageal varices. The other patients were followed up for 2 years, and the severity of esophageal and gastric varices gradually changed from severe varices with red color sign to moderate and mild varices and even disappeared. The proportion of patients with mild and disappeared varices increased from 22% on day 3 after surgery to 52% in the second year after surgery. No patients experienced rebleeding within 1 month after surgery. Six patients each experienced rebleeding at 2, 6, 10, 14, 16, and 24 months after surgery, and in one patient, duodenal bulbar ulcer and bleeding was not excluded; the other 5 patients experienced gastric variceal bleeding again, with a median portal vein pressure of 36.46 mmHg before surgery and 24.8 mmHg after surgery, with a 32% reduction in portal vein pressure. ConclusionTIPS has a good clinical effect in hemostasis and prevention of rebleeding in patients with cirrhotic portal hypertension and can control the portal vein pressure below 21.21±2.90 mmHg, and the degree of reduction in portal vein pressure is below 36%-40%. It can reduce the incidence of postoperative rebleeding and avoid the development of hepatic encephalopathy. TIPS can cause liver impairment within a short period of time after surgery, and liver function can return to normal within 1-6 months after surgery, but splenic function does not recover significantly.

The Knowledge Portal

Data.gov (United States)

Office of Personnel Management — Information on various courses, as well as personal data of employees and training records from The Knowledge Portal (TKP), a web-based training portal used for the...

Kinematics of partial and total ruptures of the medial collateral ligament of the elbow

DEFF Research Database (Denmark)

Eygendaal, D; Olsen, Bo Sanderhoff; Jensen, Steen Lund

2000-01-01

In this study the kinematics of partial and total ruptures of the medial collateral ligament of the elbow are investigated. After selective transection of the medial collateral ligament of 8 osteoligamentous intact elbow preparations was performed, 3-dimensional measurements of angular displacement......, increase in medial joint opening, and translation of the radial head were examined during application of relevant stress. Increase in joint opening was significant only after complete transection of the anterior part of the medial collateral ligament was performed. The joint opening was detected during...... valgus and internal rotatory stress only. After partial transection of the anterior bundle of the medial collateral ligament was performed, there was an elbow laxity to valgus and internal rotatory force, which became significant after transection of 100% of the anterior bundle of the medial collateral...

Portals people, processes, technology

CERN Document Server

Cox, Andrew

2006-01-01

First applied to internet gateways such as Yahoo, the concept of the ""portal"" has evolved in a number of directions. How can information services best take advantage of internet portals to improve access to resources? This collection seeks answers to such questions, providing an overview of how portals are being used.

Independent predictors of retrograde failure in CTO-PCI after successful collateral channel crossing.

Science.gov (United States)

Suzuki, Yoriyasu; Muto, Makoto; Yamane, Masahisa; Muramatsu, Toshiya; Okamura, Atsunori; Igarashi, Yasumi; Fujita, Tsutomu; Nakamura, Shigeru; Oida, Akitsugu; Tsuchikane, Etsuo

2017-07-01

To evaluate factors for predicting retrograde CTO-PCI failure after successful collateral channel crossing. Successful guidewire/catheter collateral channel crossing is important for the retrograde approach in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). A total of 5984 CTO-PCI procedures performed in 45 centers in Japan from 2009 to 2012 were studied. The retrograde approach was used in 1656 CTO-PCIs (27.7%). We investigated these retrograde procedures to evaluate factors for predicting retrograde CTO-PCI failure even after successful collateral channel crossing. Successful guidewire/catheter collateral crossing was achieved in 77.1% (n = 1,276) of 1656 retrograde CTO-PCI procedures. Retrograde procedural success after successful collateral crossing was achieved in 89.4% (n = 1,141). Univariate analysis showed that the predictors for retrograde CTO-PCI failure were in-stent occlusion (OR = 1.9829, 95%CI = 1.1783 - 3.3370 P = 0.0088), calcified lesions (OR = 1.9233, 95%CI = 1.2463 - 2.9679, P = 0.0027), and lesion tortuosity (OR = 1.5244, 95%CI = 1.0618 - 2.1883, P = 0.0216). On multivariate analysis, lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing (OR = 1.3472, 95%CI = 1.0614 - 1.7169, P = 0.0141). The success rate of retrograde CTO-PCI following successful guidewire/catheter collateral channel crossing was high in this registry. Lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing. Devices and techniques to overcome complex CTO lesion morphology, such as lesion calcification, are required to further improve the retrograde CTO-PCI success rate. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Wall shear stress in portal vein of cirrhotic patients with portal hypertension.

Science.gov (United States)

Wei, Wei; Pu, Yan-Song; Wang, Xin-Kai; Jiang, An; Zhou, Rui; Li, Yu; Zhang, Qiu-Juan; Wei, Ya-Juan; Chen, Bin; Li, Zong-Fang

2017-05-14

To investigate wall shear stress (WSS) magnitude and distribution in cirrhotic patients with portal hypertension using computational fluid dynamics. Idealized portal vein (PV) system models were reconstructed with different angles of the PV-splenic vein (SV) and superior mesenteric vein (SMV)-SV. Patient-specific models were created according to enhanced computed tomography images. WSS was simulated by using a finite-element analyzer, regarding the blood as a Newtonian fluid and the vessel as a rigid wall. Analysis was carried out to compare the WSS in the portal hypertension group with that in healthy controls. For the idealized models, WSS in the portal hypertension group (0-10 dyn/cm 2 ) was significantly lower than that in the healthy controls (10-20 dyn/cm 2 ), and low WSS area (0-1 dyn/cm 2 ) only occurred in the left wall of the PV in the portal hypertension group. Different angles of PV-SV and SMV-SV had different effects on the magnitude and distribution of WSS, and low WSS area often occurred in smaller PV-SV angle and larger SMV-SV angle. In the patient-specific models, WSS in the cirrhotic patients with portal hypertension (10.13 ± 1.34 dyn/cm 2 ) was also significantly lower than that in the healthy controls ( P portal hypertension, the low WSS area extended to wider levels and the magnitude of WSS reached lower levels, thereby being more prone to disturbed flow occurrence. Cirrhotic patients with portal hypertension show dramatic hemodynamic changes with lower WSS and greater potential for disturbed flow, representing a possible causative factor of PV thrombosis.

Regional blood flows by the microsphere method: reproducibility in portal hypertensive rats and influence of a portal vein catheter

International Nuclear Information System (INIS)

Hadengue, A.; Lee, S.S.; Koshy, A.; Girod, C.; Lebrec, D.

1988-01-01

To determine the reproducibility of splanchnic blood flow measurements by the microsphere method in rats with portal hypertension and the effects of laparotomy with portal vein cannulation, eight groups of 10 rats were studied. Microspheres were labelled with 113 Sn or 141 Ce. Laparotomy with portal cannulation had no significant effect in sham-operated rats. In awake portal hypertensive rats, cardiac output and splanchnic blood flow were lower in portal vein cannulated rats compared with those of non-cannulated animals. In anesthetized portal hypertensive rats blood flows were unaffected by portal cannulation, but arterial pressure and heart rate were elevated. Anesthesia also decreased portal pressure in portal hypertensive rats. We conclude that the microsphere method remains reproducible in portal hypertensive rat models. Laparotomy with portal cannulation can alter systemic and splanchnic hemodynamics in portal hypertensive rats; these effects can also be changed during pentobarbital anesthesia. Regional blood flow measurements in portal hypertensive rats should be performed in animals without portal cannulation and preferably in the awake state

7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

Science.gov (United States)

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a loan...

Applications of portals in the energetic sector; Aplicaciones de portales en el sector energetico

Energy Technology Data Exchange (ETDEWEB)

Santos Dominguez, Martin; Arroyo Figueroa, Gustavo [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

2000-07-01

An operative portal joins the applications, contents and services of the company in a single page of Intranet such way that promises to change deeply the information technology in the next years. The corporative portals will change what people visualize in the screen of their computer at the beginning of every working day. Unlike seeing the network (Web) only with pages of language of hypertext bearing (HTML), the corporative portal acts as a gate between Internet and the private networks. This article presents a general vision of the benefits of the corporative portals, the existing technologies and the potential markets. [Spanish] Un portal operativo une las aplicaciones, contenidos y servicios de la empresa en una sola pagina de Intranet, de tal forma que promete cambiar, profundamente la tecnologia de la informacion en los proximos anos. Los portales corporativos cambiaran lo que la gente visualiza en la pantalla de su computadora al comienzo de cada dia de trabajo. A diferencia de ver la red (Web) solo con paginas de lenguaje de marcacion de hipertexto (HTML), el portal corporativo actua como compuerta entre Internet y las redes privadas. Este articulo presenta una vision general de los beneficios de los portales corporativos, las tecnologias y los mercados potenciales existentes.

31 CFR 363.176 - May a converted savings bond be pledged or used as collateral?

Science.gov (United States)

2010-07-01

... pledged or used as collateral? 363.176 Section 363.176 Money and Finance: Treasury Regulations Relating to... a converted savings bond be pledged or used as collateral? A converted savings bond may not be pledged or used as collateral for the performance of an obligation. ...

[Regional liver circulation and the scintigraphic representation of the portal circulation with 133Xe].

Science.gov (United States)

Kroiss, A

1984-01-01

Regional hepatic blood flow has been determined by 4 methods with the aid of the 133Xe washout technique: scintisplenoportography (direct application of 133Xe into the spleen by means of a thin needle); arterial method (133Xe is injected into the A. hepatica by means of a catheter); retrograde-venous method (133Xe administered by an occluding hepatic vein catheter); percutaneous intrahepatic method (133Xe administered directly into the parenchyma by means of a Chiba needle). Ad 1.: Scintisplenoportography (SSP) was executed with 97 patients: 8 patients with a healthy liver presented a hepatic blood flow of 103.37 +/- 11.5 ml/100 g/min. 4 patients with a chronic hepatitis showed a hepatic blood flow of 105.67 +/- 10.2 ml/100 g/min. In 38 patients with compensated cirrhosis, hepatic blood flow was determined with 58.15 +/- 11.5 ml/100 g/min and 19 patients with decompensated cirrhosis showed a blood flow of 34.54 +/- 7.2 ml/100 g/min. Of the 19 patients, who did not present any liver image, 2 patients suffered from a prehepatic block, 1 patient (female) from a posthepatic block, the rest were decompensated cirrhoses. In 5 patients suffering from steatosis only collateral circulation was determined and in 4 patients the spleen could not be punctured. In the patients with compensated and decompensated cirrhosis of the liver, hepatic blood flow differentiated significantly (p less than 0.001) from patients with healthy livers and chronic hepatitis. In the patients with bioptically assured steatosis only the washout constant was determined. Reproducibility of this method was tested in 4 patients and no statistical difference of hepatic blood flow values could be found and the correlation coefficient amounted to 0.9856. The advantage of SSP lies in the possibility of recording the portal vein circulation: cranial collaterals were found in 33 patients, 2 patients had caudal collaterals exclusively and 29 patients cranial and caudal collaterals. 33 cirrhosis patients

Differential impact of diabetes mellitus type II and arterial hypertension on collateral artery growth and concomitant macrophage accumulation.

Science.gov (United States)

Ito, Wulf D; Lund, Natalie; Sager, Hendrik; Becker, Wiebke; Wenzel, Ulrich

2015-01-01

Diabetes mellitus type II and arterial hypertension are major risk factors for peripheral arterial disease and have been considered to reduce collateral growth (arteriogenesis). Collateral growth proceeds through different stages. Vascular proliferation and macrophage accumulation are hallmarks of early collateral growth. We here compare the impact of arterial hypertension and diabetes mellitus type II on collateral proliferation (Brdu incorporation) and macrophage accumulation (ED 2 staining) as well as collateral vessel function (collateral conductance) in a rat model of peripheral vascular disease (femoral artery occlusion), diabetes mellitus type II (Zucker fatty diabetic rats and Zucker lean rat controls) and arterial hypertension (induced via clip placement around the right renal arteriy). We furthermore tested the impact of monocyte chemoattractant protein-1 (MCP‑1) on collateral proliferation and macrophage accumulation in these models Diabetic animals showed reduced vascular proliferation and macrophage accumulation, which however did not translate into a change of collateral conductance. Hypertensive animals on the contrary had reduced collateral conductances without altered macrophage accumulation and only a marginal reduction in collateral proliferation. Infusion of MCP‑1 only enhanced vascular proliferation in diabetic animals. These findings illustrate that impaired monocyte/macrophage recruitment is responsible for reduced collateral growth under diabetic conditions but not in arterial hypertension suggesting that diabetes mellitus in particular affects early stages of collateral growth whereas hypertension has its impact on later remodeling stages. Successful pro-arteriogenic treatment strategies in a patient population that presents with diabetes mellitus and arterial hypertension need to address different stages of collateral growth and thus different molecular and cellular targets simultaneously.

Effects of glucose ingestion on hepatic hemodynamics in patients with liver disease by per-rectal portal scintigraphy using 99mTcO4- (direct intramural administration of radioisotope method)

International Nuclear Information System (INIS)

Tetsuka, Isando; Ohe, Takashi; Harada, Takashi

1992-01-01

Effect of glucose (225 ml, 300 kcal) ingestion on hepatic hemodynamics was studied in ten patients with liver cirrhosis and eight patients with non cirrhotic liver disease by per-rectal portal scintigraphy using 99m TcO 4 - (direct intramural administration of radioisotope method). Initial portal blood flow index (IP) and collateral index (CI) were calculated from the time activity curve of heart and liver. The value of IP was not significantly changed between before and after glucose ingestion in cases of liver cirrhosis (before: 0.0160±0.0016, after: 0.0204±0.0106). In cases of non cirrhotic liver disease, the value of IP was significantly increased after glucose ingestion (before: 0.0381±0.0145, after: 0.0544±0.0194, p<0.02). These findings suggested increase in portal blood flow via inferior mesenteric vein to the cardiac blood flow. The value of CI before glucose ingestion was significantly increased in cases of liver cirrhosis (0.751±0.156) compared with that in cases of non cirrhotic liver disease (0.517±0.122), but no significant difference in values after glucose ingestion was found between these two groups. (author)

[As cardioprotective and angiogenic biomarker, can ghrelin predict coronary collateral development and severity of coronary atherosclerosis?

Science.gov (United States)

Akboğa, Mehmet Kadri; Taçoy, Gülten; Yılmaz Demirtaş, Canan; Türkoğlu, Sedat; Boyacı, Bülent; Çengel, Atiye

2017-06-01

Ghrelin exerts protective effects on cardiovascular system by inhibiting progression of atherosclerosis, supression of vascular inflammation, and stimulating angiogenesis. Thus, the aim of this study was to investigate the effect of serum ghrelin on coronary collateral development and SYNTAX score in patients with severe coronary artery disease. Total of 91 patients who had ≥90% stenosis in at least one major coronary artery were prospectively included in this cross-sectional, observational study. Collateral degree was graded according to Rentrop-Cohen classification. Patients with grade 2 or 3 collateral degree were allocated to Good Collateral Group and patients with grade 0 or 1 collateral degree were included in Poor Collateral Group. Ghrelin and vascular endothelial growth factor A (VEGF-A) levels were measured using radioimmunoassay and ELISA kits. Serum ghrelin and VEGF-A levels were significantly higher in Good Collateral Group. Furthermore, ghrelin level showed significant inverse correlation with SYNTAX score (r=0.348; p=0.001). In multivariable regression analysis, ghrelin (Odds ratio, 1.013; 95% confidence interval, 1.011-1.017; p=0.013), VEGF-A, fasting plasma glucose and presence of chronic total occlusion were independent predictors of good collateral development. In receiver operating characteristic curve analysis, ghrelin value cut-off point of ≥781 pg/mL predicted good collateral development with sensitivity of 73.1% and specificity of 67.7%. Findings suggested that ghrelin has antioxidant and antiinflammatory properties that protect endothelial functions and also stimulate angiogenesis, which results in development of good coronary collateral and inhibition of progression of coronary atherosclerosis.

Significance of collateral circulation on peri-infarct zone: assessment with stress thallium-201 scintigraphy

International Nuclear Information System (INIS)

Imamura, T.; Araki, H.; Fukuyama, T.; Maruoka, Y.; Ootsubo, H.; Nakamura, M.; Koiwaya, Y.; Tanaka, K.

1986-01-01

To evaluate the significance of collateral circulation on peri-infarct zone, stress myocardial scintigraphy and contrast left ventriculography (LVG) were performed in 38 patients with recent myocardial infarction (MI). All patients had at least one completely occluded coronary artery corresponding to the infarct area. In patients with good collaterals, stress induced transient enlargement of the perfusion defect, however, in those with poor or no collaterals the enlargement did not occur (p less than 0.05). Wall motion abnormality on LVG was significantly milder in the former patients than in the latter (p less than 0.001). Transient enlargement of the perfusion defect after stress and milder left ventricular asynergy were more frequently observed in patients with anterior MI and good collaterals. These observations indicate that good collaterals may keep some myocardium in the peri-infarct zone viable

Impact of Collateral Status on Successful Revascularization in Endovascular Treatment: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Leng, Xinyi; Fang, Hui; Leung, Thomas W H; Mao, Chen; Xu, Yuming; Miao, Zhongrong; Liu, Liping; Wong, K S Lawrence; Liebeskind, David S

2016-01-01

Pre-treatment collateral status may be associated with the rates of successful revascularization in acute ischemic stroke patients receiving endovascular treatment (EVT). We conducted a systematic review and meta-analysis to synthesize relevant evidence currently available. Relevant full-text articles published in English since January 1, 2000, reporting associations between collateral status and successful reperfusion and/or recanalization in acute ischemic stroke patients receiving EVT in cohort or case-control studies, or randomized clinical trials, were retrieved through search of PubMed. Study selection, data extraction and study quality assessment were carried out by 2 investigators. Risk ratios (RR) were pooled for good vs. poor collaterals for the outcomes of successful reperfusion and recanalization, based on random-effects models. Subgroup analyses were conducted to explore for potential factors that might interfere with the effects of pre-treatment collateral status on reperfusion by EVT. In total, 27 studies (2,366 subjects) were included in qualitative analysis, among which 24 studies (2,239 subjects) were quantitatively analyzed. Overall, good pre-treatment collaterals significantly increased the rate of both successful reperfusion (RR 1.28, 95% CI 1.17-1.40; p collaterals. Subgroup analyses revealed that the effects of collateral status on successful reperfusion by EVT might be different between populations with different ethnicities. Good pre-treatment collaterals may enhance the rates of successful reperfusion and recanalization in EVT for acute ischemic stroke. This may partly explain the favorable effects of good pre-treatment collaterals on clinical outcomes of stroke patients receiving EVT. Thus, it would be valuable to assess the collateral status prior to EVT in acute ischemic stroke. But studies are needed to further verify if the positive effects of good collaterals on revascularization by EVT are restricted to certain subgroups of patients

Collateral Determinats In Bank Risk Mananagement: The Regional Case

Directory of Open Access Journals (Sweden)

A. M. Karminsky

2018-01-01

Full Text Available Regional banks are struggling with significant obstacles in the modern Russian economy. Among them are strong competition with major big banks, strong resource restrictions, tightening the Bank of Russia’s requirements, and quite rapid expansion of financial technologies. Thus, the reduction of regional banks occurs, that produces both a negative impact on the development of small and medium enterprises (SMEs and challenges for balanced competition on the Russian market. Basically, these banks provide the settlement of region’s social and economic problems while maintaining local companies and enterprises. Collateral, as a source for losses covering, became the essential element of credit risk management in banks. Providing lenders to implement such instruments, it helps to reduce bank losses under borrower’s default. The purpose of the article relates to revealing of collateral determinants with higher impact on bank risk with the application of empirical methods (including regional level. This study is based on linear regression models evaluated by the least square method. Private data of secured small and medium business loans is used. This article presents LTV (loan-to-value as a major collateral determinant. The empirical evidence of interlinkage between collateral requirements, by the means of LTV, and risk premium is provided for loan portfolio of Russian regional banks. The hypothesis that LTV conversely correlates with risk premium is statistically proved.

Coronary collateral circulation and its effect on myocardial infarction

International Nuclear Information System (INIS)

Fukuyama, Takaya; Ashihara, Toshiaki; Ogata, Ikuo

1995-01-01

The purpose of this study was to examine the influence of coronary collateral circulation, which grows after acute myocardial infarction (MI), on infarct size and prognosis. Study subjects were 47 patients who had arteriographic evidence of 99-100% constricture of the infarct-related artery approximately one month after the onset of the first MI. Coronary collateral circulation was analyzed by a four-point scoring (grade 0-3). Furthermore, the patients underwent thallium-201 myocardial imaging one month and two years after the onset to evaluate infarct size. Infarct size was analyzed using extent score (ES) and severity score (SS). ES tended to be decreased during chronic MI stage. Coronary collateral circulation was judged as grade 1 (n=9), grade 2 (n=12), and grade 3 (n=26). There was no difference in infarct size among the three groups. In groups of grades 1 and 2, there was no difference in ES and SS between acute and chronic MI stages. In the group of grade 3, however, ES decreased from 41% to 27% and SS decreased from 68% to 38%, showing remarkable decrease during chronic MI stage. Although coronary collateral circulation one month after the onset is not always responsible for infarct size during acute MI stage, it is considered rsponsible for inhibiting the remodeling of infarction through the long term process. (N.K.)

Embolization for Thoracic Duct Collateral Leakage in High-Output Chylothorax After Thoracic Surgery

International Nuclear Information System (INIS)

Kariya, Shuji; Nakatani, Miyuki; Yoshida, Rie; Ueno, Yutaka; Komemushi, Atsushi; Tanigawa, Noboru

2017-01-01

PurposeThis study was designed to investigate thoracic duct collateral leakage and the supply route of lymphatic fluid by lymphangiography and transcatheter thoracic ductography and to evaluate the results of embolization for thoracic duct collateral leakage performed to cut off this supply route.MethodsData were retrospectively collected from five patients who underwent embolization for thoracic duct collateral leakage in persistent high-output chylothorax after thoracic surgery. Extravasation of lipiodol at the ruptured thoracic duct collaterals was confirmed in all patients on lymphangiography. Transcatheter thoracic ductography was used to identify extravasation of iodinated contrast agent and to identify communication between the thoracic duct and leakage site. Thoracic duct embolization (TDE) was performed using the percutaneous transabdominal approach to cut off the supply route using N-butyl cyanoacrylate (NBCA) mixed with lipiodol (1:5–1:20).ResultsClinical success (drainage volume ≤10 mL/kg/day within 7 days after TDE) was achieved in all patients. The collateral routes developed as consequence of surgical thoracic duct ligation. In three patients, NBCA-Lipiodol reached the leakage site through direct communication between the thoracic duct and the ruptured lymphatic duct. In the other two patients, direct communication and extravasation was not detected on thoracic ductography, and NBCA-Lipiodol did not reach the leakage site. However, NBCA-Lipiodol did reach the cisterna chyli, lumbar trunks, and some collateral routes via the cisterna chyli or lumbar lymphatics. As a result, leakage was stopped.ConclusionsTDE was effective for the management of leakage of the collaterals in high-output chylothorax after thoracic surgery.

Embolization for Thoracic Duct Collateral Leakage in High-Output Chylothorax After Thoracic Surgery

Energy Technology Data Exchange (ETDEWEB)

Kariya, Shuji, E-mail: kariyas@hirakata.kmu.ac.jp; Nakatani, Miyuki, E-mail: nakatanm@hirakata.kmu.ac.jp; Yoshida, Rie, E-mail: yagir@hirakata.kmu.ac.jp; Ueno, Yutaka, E-mail: uenoyut@hirakata.kmu.ac.jp; Komemushi, Atsushi, E-mail: komemush@takii.kmu.ac.jp; Tanigawa, Noboru, E-mail: tanigano@hirakata.kmu.ac.jp [Kansai Medical University, Department of Radiology (Japan)

2017-01-15

PurposeThis study was designed to investigate thoracic duct collateral leakage and the supply route of lymphatic fluid by lymphangiography and transcatheter thoracic ductography and to evaluate the results of embolization for thoracic duct collateral leakage performed to cut off this supply route.MethodsData were retrospectively collected from five patients who underwent embolization for thoracic duct collateral leakage in persistent high-output chylothorax after thoracic surgery. Extravasation of lipiodol at the ruptured thoracic duct collaterals was confirmed in all patients on lymphangiography. Transcatheter thoracic ductography was used to identify extravasation of iodinated contrast agent and to identify communication between the thoracic duct and leakage site. Thoracic duct embolization (TDE) was performed using the percutaneous transabdominal approach to cut off the supply route using N-butyl cyanoacrylate (NBCA) mixed with lipiodol (1:5–1:20).ResultsClinical success (drainage volume ≤10 mL/kg/day within 7 days after TDE) was achieved in all patients. The collateral routes developed as consequence of surgical thoracic duct ligation. In three patients, NBCA-Lipiodol reached the leakage site through direct communication between the thoracic duct and the ruptured lymphatic duct. In the other two patients, direct communication and extravasation was not detected on thoracic ductography, and NBCA-Lipiodol did not reach the leakage site. However, NBCA-Lipiodol did reach the cisterna chyli, lumbar trunks, and some collateral routes via the cisterna chyli or lumbar lymphatics. As a result, leakage was stopped.ConclusionsTDE was effective for the management of leakage of the collaterals in high-output chylothorax after thoracic surgery.

Hyperintense vessels on FLAIR: A useful non-invasive method for assessing intracerebral collaterals

International Nuclear Information System (INIS)

Liu Wenhua; Xu Gelin; Yue Xuanye; Wang Xiaoliang; Ma Minmin; Zhang Renliang; Wang Handong; Zhou Changsheng; Liu Xinfeng

2011-01-01

Objective: This study was aimed to evaluate relationship between hyperintense vessels (HV) on fluid-attenuated inversion recovery (FLAIR) and artery steno-occlusion related intracerebral collaterals. Materials and methods: A total of 233 patients with 260 atherosclerotic lesions in the M1 segment of the middle cerebral artery (MCA) were examined with FLAIR and digital subtraction angiography (DSA). HV were graded as 0, 1, 2 and 3 by its distributions in the MCA territory. Grade 0 indicated no HV; Grade 1 indicated the HV limited in Sylvian fissure; Grade 2 indicated the HV limited in Sylvian fissure and the temporal-occipital junction; Grade 3 indicated the HV extended to frontal-parietal lobes. Collateral blood flows were classified by DSA results. The relationship between HV grades and patterns of collateral flows was analyzed. Results: HV were observed in 76 out of 260 hemispheres. For patients with Grade 1 HV, most of their collateral flows (80.8%) were antegrade; for patients with Grade 2, the retrograde leptomeningeal flows were commonly manifested as anterior cerebral artery to MCA (75%); for patients with Grade 3 HV, most of the retrograde leptomeningeal flows were manifested as posterior cerebral artery to MCA (81.8%). As the grade HV increased, the frequency of retrograde leptomeningeal collateral from ACA to MCA decreased (100% to 75% and to 18.2%), and increased (0% to 25% and to 81.8%) for the retrograde leptomeningeal collateral via PCA to MCA (P < 0.001). Conclusions: The HV could assess non-invasively intracerebral collaterals in patients with steno-occlusive lesions of M1 segment of MCA.

From EGEE Operations Portal towards EGI Operations Portal

Science.gov (United States)

Cordier, Hélène; L'Orphelin, Cyril; Reynaud, Sylvain; Lequeux, Olivier; Loikkanen, Sinikka; Veyre, Pierre

Grid operators in EGEE have been using a dedicated dashboard as their central operational tool, stable and scalable for the last 5 years despite continuous upgrade from specifications by users, monitoring tools or data providers. In EGEE-III, recent regionalisation of operations led the Operations Portal developers to conceive a standalone instance of this tool. We will see how the dashboard reorganization paved the way for the re-engineering of the portal itself. The outcome is an easily deployable package customized with relevant information sources and specific decentralized operational requirements. This package is composed of a generic and scalable data access mechanism, Lavoisier; a renowned php framework for configuration flexibility, Symfony and a MySQL database. VO life cycle and operational information, EGEE broadcast and Downtime notifications are next for the major reorganization until all other key features of the Operations Portal are migrated to the framework. Features specifications will be sketched at the same time to adapt to EGI requirements and to upgrade. Future work on feature regionalisation, on new advanced features or strategy planning will be tracked in EGI- Inspire through the Operations Tools Advisory Group, OTAG, where all users, customers and third parties of the Operations Portal are represented from January 2010.

Cerebral collateral therapeutics in acute ischemic stroke: A randomized preclinical trial of four modulation strategies.

Science.gov (United States)

Beretta, Simone; Versace, Alessandro; Carone, Davide; Riva, Matteo; Dell'Era, Valentina; Cuccione, Elisa; Cai, Ruiyao; Monza, Laura; Pirovano, Silvia; Padovano, Giada; Stiro, Fabio; Presotto, Luca; Paternò, Giovanni; Rossi, Emanuela; Giussani, Carlo; Sganzerla, Erik P; Ferrarese, Carlo

2017-10-01

Cerebral collaterals are dynamically recruited after arterial occlusion and highly affect tissue outcome in acute ischemic stroke. We investigated the efficacy and safety of four pathophysiologically distinct strategies for acute modulation of collateral flow (collateral therapeutics) in the rat stroke model of transient middle cerebral artery (MCA) occlusion. A composed randomization design was used to assign rats (n = 118) to receive phenylephrine (induced hypertension), polygeline (intravascular volume load), acetazolamide (cerebral arteriolar vasodilation), head down tilt (HDT) 15° (cerebral blood flow diversion), or no treatment, starting 30 min after MCA occlusion. Compared to untreated animals, treatment with collateral therapeutics was associated with lower infarct volumes (62% relative mean difference; 51.57 mm 3 absolute mean difference; p Collateral therapeutics acutely increased cerebral perfusion in the medial (+40.8%; p collaterals is feasible and provides a tissue-saving effect in the hyperacute phase of ischemic stroke prior to recanalization therapy.

The effect of partial portal decompression on portal blood flow and effective hepatic blood flow in man: a prospective study.

Science.gov (United States)

Rosemurgy, A S; McAllister, E W; Godellas, C V; Goode, S E; Albrink, M H; Fabri, P J

1995-12-01

With the advent of transjugular intrahepatic porta-systemic stent shunt and the wider application of the surgically placed small diameter prosthetic H-graft portacaval shunt (HGPCS), partial portal decompression in the treatment of portal hypertension has received increased attention. The clinical results supporting the use of partial portal decompression are its low incidence of variceal rehemorrhage due to decreased portal pressures and its low rate of hepatic failure, possibly due to maintenance of blood flow to the liver. Surprisingly, nothing is known about changes in portal hemodynamics and effective hepatic blood flow following partial portal decompression. To prospectively evaluate changes in portal hemodynamics and effective hepatic blood flow brought about by partial portal decompression, the following were determined in seven patients undergoing HGPCS: intraoperative pre- and postshunt portal vein pressures and portal vein-inferior vena cava pressure gradients, intraoperative pre- and postshunt portal vein flow, and pre- and postoperative effective hepatic blood flow. With HGPCS, portal vein pressures and portal vein-inferior vena cava pressure gradients decreased significantly, although portal pressures remained above normal. In contrast to the significant decreases in portal pressures, portal vein blood flow and effective hepatic blood flow do not decrease significantly. Changes in portal vein pressures and portal vein-inferior vena cava pressure gradients are great when compared to changes in portal vein flow and effective hepatic blood flow. Reduction of portal hypertension with concomitant maintenance of hepatic blood flow may explain why hepatic dysfunction is avoided following partial portal decompression.

31 CFR 363.58 - May book-entry savings bonds be pledged or used as collateral?

Science.gov (United States)

2010-07-01

... pledged or used as collateral? 363.58 Section 363.58 Money and Finance: Treasury Regulations Relating to...Direct General § 363.58 May book-entry savings bonds be pledged or used as collateral? Bonds may not be pledged or used as collateral for the performance of an obligation. ...

Collateral flow as causative of good outcomes in endovascular stroke therapy.

Science.gov (United States)

Sheth, Sunil A; Sanossian, Nerses; Hao, Qing; Starkman, Sidney; Ali, Latisha K; Kim, Doojin; Gonzalez, Nestor R; Tateshima, Satoshi; Jahan, Reza; Duckwiler, Gary R; Saver, Jeffrey L; Vinuela, Fernando; Liebeskind, David S

2016-01-01

Endovascular reperfusion techniques are a promising intervention for acute ischemic stroke (AIS). Prior studies have identified markers of initial injury (arrival NIH stroke scale (NIHSS) or infarct volume) as predictive of outcome after these procedures. We sought to define the role of collateral flow at the time of presentation in determining the extent of initial ischemic injury and its influence on final outcome. Demographic, clinical, laboratory, and radiographic data were prospectively collected on a consecutive cohort of patients who received endovascular therapy for acute cerebral ischemia at a single tertiary referral center from September 2004 to August 2010. Higher collateral grade as assessed by the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grading scheme on angiography at the time of presentation was associated with improved reperfusion rates after endovascular intervention, decreased post-procedural hemorrhage, smaller infarcts on presentation and discharge, as well as improved neurological function on arrival to the hospital, discharge, and 90 days later. Patients matched by vessel occlusion, age, and time of onset demonstrated smaller strokes on presentation and better functional and radiographic outcome if found to have superior collateral flow. In multivariate analysis, lower collateral grade independently predicted higher NIHSS on arrival. Improved collateral flow in patients with AIS undergoing endovascular therapy was associated with improved radiographic and clinical outcomes. Independent of age, vessel occlusion and time, in patients with comparable ischemic burdens, changes in collateral grade alone led to significant differences in initial stroke severity as well as ultimate clinical outcome. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

The significance of collateral vessels, as seen on chest CT, in predicting SVC obstruction

International Nuclear Information System (INIS)

Yeouk, Young Soo; Kim, Sung Jin; Bae, Il Hun; Kim, Jae Youn; Hwang, Seung Min; Han, Gi Seok; Park, Kil Sun; Kim, Dae Young

1998-01-01

To evaluate the significance of collateral veins, as seen on chest CT, in the diagnosis of superior vena cava obstruction. We retrospectively the records of 81 patients in whom collateral veins were seen on chest CT. On spiral CT(n=49), contrast material was infused via power injector, and on conventional CT(n=32), 50 ml bolus infusion was followed by 50 ml drip infusion. Obstruction of the SVC was evaluated on chest CT; if, however, evaluation of the SVC of its major tributaries was difficult, as in five cases, the patient underwent SVC phlebography. Collateral vessels were assigned to one of ten categories. On conventional CT, the jugular venous arch in the only collateral vessel to predict SVC obstruction; on spiral CT, however, collateral vessels are not helpful in the diagnosis of SVC obstruction, but are a nonspecific finding. (author). 12 refs., 2 tab., 2 figs

The effects of medial ulnar collateral ligament reconstruction on Major League pitching performance.

Science.gov (United States)

Keller, Robert A; Steffes, Matthew J; Zhuo, David; Bey, Michael J; Moutzouros, Vasilios

2014-11-01

Medial ulnar collateral ligament (MUCL) reconstruction is commonly performed on Major League Baseball (MLB) pitchers. Previous studies have reported that most pitchers return to presurgical statistical performance levels after MUCL reconstruction. Pitching performance data--specifically, earned run average (ERA), walks and hits per inning pitched (WHIP), winning percentage, and innings pitched--were acquired for 168 MLB pitchers who had undergone MUCL reconstruction. These data were averaged over the 3 years before surgery and the 3 years after surgery and also acquired from 178 age-matched, uninjured MLB pitchers. Of the pitchers who had MUCL reconstruction surgery, 87% returned to MLB pitching. However, compared with presurgical data, pitching performance declined in terms of ERA (P = .001), WHIP (P = .011), and innings pitched (P = .026). Pitching performance also declined in the season before the surgery compared with previous years (ERA, P = .014; WHIP, P = .036; innings pitched, P risk factor for requiring surgery. In addition, there is an increased risk of MUCL reconstruction for pitchers who enter the major leagues at a younger age. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Magnetic Resonance Imaging of a Liver Hydatid Cyst Invading the Portal Vein and Causing Portal Cavernomatosis.

Science.gov (United States)

Herek, Duygu; Sungurtekin, Ugur

2015-01-01

Hepatic hydatid cysts rarely invade portal veins causing portal cavernomatosis as a secondary complication. We report the case of a patient with direct invasion of the right portal vein by hydatid cysts causing portal cavernomatosis diagnosed via magnetic resonance imaging (MRI). The presented case highlights the useful application of MRI with T2-weighted images and gadolinium-enhanced T1-weighted images in the diagnosis of hepatic hydatid lesions presenting with a rare complication of portal cavernomatosis.

31 CFR 363.146 - May a certificate of indebtedness be pledged or used as collateral?

Science.gov (United States)

2010-07-01

... pledged or used as collateral? 363.146 Section 363.146 Money and Finance: Treasury Regulations Relating to... certificate of indebtedness be pledged or used as collateral? A certificate of indebtedness may not be pledged or used as collateral for the performance of an obligation. [69 FR 50309, Aug. 16, 2004. Redesignated...

Influence of risk area size and location on native collateral resistance and ischemic zone perfusion

International Nuclear Information System (INIS)

Gumm, D.C.; Cooper, S.M.; Thompson, S.B.; Marcus, M.L.; Harrison, D.C.

1988-01-01

To examine the effect of risk area size on collateral resistance and ichemic region perfusion, the authors produced different sized risk areas by occluding either the left anterior descending (LAD) or the circumflex (Cx) coronary artery at different sites. The most proximal occlusion of the LAD and Cx produced risk areas of 43 ± 5 and 36 ± 2% of left ventricular (LV) mass, respectively, whereas distal LAD and Cx occlusions produced risk areas of 13 ± 2 and 17 ± 2% of LV weight, respectively. Although total collateral flow was highest to the largest risk areas, collateral flow per 100 g of ischemic myocardium was 80% higher to the small LAD risk area compared with the large LAD risk area and 43% higher to the small Cx risk area compared with the large Cx risk area. Collateral resistance, calculated from the transcollateral pressure and perfusion per 100 g of myocardium was significantly lower in the small risk areas than in the large ones. They examined the effect of risk area location on collateral perfusion and resistance. These experiments show that collateral resistance is influenced both by ischemic region size and location. Small risk areas receive more collateral flow per mass of tissue than large risk areas, and apical risk areas receive greater quantities of collateral flow than those located at the base. These data may explain why small risk areas often do not develop infarction after coronary occlusion

Impaired Leptomeningeal Collateral Flow Contributes to the Poor Outcome following Experimental Stroke in the Type 2 Diabetic Mice

Science.gov (United States)

Akamatsu, Yosuke; Nishijima, Yasuo; Lee, Chih Cheng; Yang, Shih Yen; Shi, Lei; An, Lin; Wang, Ruikang K.; Tominaga, Teiji

2015-01-01

Collateral status is an independent predictor of stroke outcome. However, the spatiotemporal manner in which collateral flow maintains cerebral perfusion during cerebral ischemia is poorly understood. Diabetes exacerbates ischemic brain damage, although the impact of diabetes on collateral dynamics remains to be established. Using Doppler optical coherent tomography, a robust recruitment of leptomeningeal collateral flow was detected immediately after middle cerebral artery (MCA) occlusion in C57BL/6 mice, and it continued to grow over the course of 1 week. In contrast, an impairment of collateral recruitment was evident in the Type 2 diabetic db/db mice, which coincided with a worse stroke outcome compared with their normoglycemic counterpart db/+, despite their equally well-collateralized leptomeningeal anastomoses. Similar to the wild-type mice, both db/+ and db/db mice underwent collateral growth 7 d after MCA stroke, although db/db mice still exhibited significantly reduced retrograde flow into the MCA territory chronically. Acutely induced hyperglycemia in the db/+ mice did not impair collateral flow after stroke, suggesting that the state of hyperglycemia alone was not sufficient to impact collateral flow. Human albumin was efficacious in improving collateral flow and outcome after stroke in the db/db mice, enabling perfusion to proximal MCA territory that was usually not reached by retrograde flow from anterior cerebral artery without treatment. Our results suggest that the impaired collateral status contributes to the exacerbated ischemic injury in mice with Type 2 diabetes, and modulation of collateral flow has beneficial effects on stroke outcome among these subjects. PMID:25740515

Colangiopatía portal: complicación poco frecuente de la hipertensión portal

OpenAIRE

Veloso, Victoria; Servente, Liliana; Hernández, Nelia

2017-01-01

Resumen: Se describe el caso clínico de una mujer de 62 años en la que se diagnostica una estenosis del colédoco en el contexto de hipertensión portal prehepática (cavernomatosis portal). Abstract: We report the case of a 62 years old woman with a choledochal stricture and chronic obstruction of the portal vein (portal cavernomatosis). Resumo: Relatamos o caso de uma mulher de 62 anos com diagnóstico de estenose do colédoco no contexto da hipertensão portal pré-hepática (cavernomat...

Insights into coronary collateral formation from a novel porcine semiacute infarction model.

Science.gov (United States)

Krackhardt, Florian; Harnoss, Jonathan M; Waliszewski, Matthias W; Ritter, Zully; Granzow, Susanne; Felsenberg, Dieter; Neumann, Konrad; Lerman, Lilian O; Hillmeister, Philipp; Gebker, Rolf; Paetsch, Ingo; Riediger, Fabian; Bramlage, Peter; Buschmann, Ivo R

2018-03-01

For patients with severe ischemic heart disease, complete revascularization by a percutaneous coronary intervention or coronary artery bypass grafting is often not achieved and may still cause residual angina. In case of progressive coronary artery occlusions, therapeutic arteriogenesis constitutes a promising strategy for increasing blood supply to the ischemic myocardium. Whether the formation of collaterals in the hypofused myocardium is angiogenetic in nature or based on preformed coronary artery anastomoses remains debatable. The objectives of this research were (i) the development of an appropriate research methodology to study a humanoid animal semiacute infarction model with low mortality and (ii) to answer the question of whether collateral revascularization follows a pre-existing 'blueprint'. A porcine model was chosen in which a step-wise vessel occlusion was performed by implantation of a copper stent into the distal left anterior descending artery. Vessel occlusion and collateral development were confirmed in vivo every 14 days up to day 56 by repeated coronary angiography and myocardial perfusion measurement using cardiac MRI. After the completion of the in-vivo imaging studies, animals were euthanized and collateral growth was evaluated using microcomputer tomography. Our porcine model of semiacute noninvasive coronary artery occlusion confirmed the existence of preformed coronary anastomoses and the proliferation of functional vessels in hypoperfused myocardium. Repetitive intra-animal MRIs showed the functional impact of these growing collaterals. The confirmation of preformed coronary anastomoses during the process of collateralization (natural bypasses) offers a preclinical avenue to carry out arteriogenetic pharmaceutical research in patients with ischemic heart disease.

The XCAT Science Portal

Directory of Open Access Journals (Sweden)

Sriram Krishnan

2002-01-01

Full Text Available This paper describes the design and prototype implementation of the XCAT Grid Science Portal. The portal lets grid application programmers script complex distributed computations and package these applications with simple interfaces for others to use. Each application is packaged as a notebook which consists of web pages and editable parameterized scripts. The portal is a workstation-based specialized personal web server, capable of executing the application scripts and launching remote grid applications for the user. The portal server can receive event streams published by the application and grid resource information published by Network Weather Service (NWS [35] or Autopilot [16] sensors. Notebooks can be published and stored in web based archives for others to retrieve and modify. The XCAT Grid Science Portal has been tested with various applications, including the distributed simulation of chemical processes in semiconductor manufacturing and collaboratory support for X-ray crystallographers.

The future of collateral artery research

NARCIS (Netherlands)

Hakimzadeh, Nazanin; Verberne, Hein J.; Siebes, Maria; Piek, Jan J.

2014-01-01

In the event of obstructive coronary artery disease, collateral arteries have been deemed an alternative blood source to preserve myocardial tissue perfusion and function. Monocytes play an important role in modulating this process, by local secretion of growth factors and extracellular matrix

28 CFR 104.47 - Collateral sources.

Science.gov (United States)

2010-07-01

... determining the appropriate collateral source offset for future benefit payments, the Special Master may employ an appropriate methodology for determining the present value of such future benefits. In... compensation, including life insurance, pension funds, death benefits programs, and payments by Federal, State...

Resiliency and collateral learning in science in some students of cree ancestry

Science.gov (United States)

Sutherland, Dawn

2005-07-01

In the context of schooling, resiliency refers to the ability to thrive academically despite adverse circumstances. In this study the relationship between academic resilience and student's collateral learning is explored in 20 students of Cree ancestry. The individual resilience of each student was examined by identifying protective factors for school leaving within the microsystem of each student's ecological framework. Student responses to questions related to motivation and engagement were ranked. In addition, students' perception of the influence of family and peers on individual attributes toward schooling was ranked.To gain insight into the collateral learning aspects of science learning in Cree students, the participants in this study were asked to reflect on their learning strategies through the use of critical incidents. The relationship between collateral learning and resiliency was also explored.This study found that students possessing a greater number of protective factors were more likely to learn science in a way described by Jegede's collateral learning theory. Responses to critical incidents indicate some Cree students hold at least two sources of knowledge to explain some science concepts and therefore may adopt a collateral learning strategy. The importance these students place on earned or experiential knowledge is evident in the interviews. Some suggestions for classroom instruction are offered in conclusion.

Anatomy of the Portal Vein Bifurcation: Implication for Transjugular Intrahepatic Portal Systemic Shunts

International Nuclear Information System (INIS)

Kwok, Philip Chong-hei; Ng, Wai Fu; Lam, Christine Suk-yee; Tsui, Polly Po; Faruqi, Asma

2003-01-01

Purpose: The relationship of the portalvein bifurcation to the liver capsule in Asians, which is an important landmark for transjugular intrahepatic portosystemic shunt, has not previously been described. Methods: The anatomy of the portal vein bifurcation was studied in 70 adult Chinese cadavers; it was characterized as intrahepatic or extrahepatic. The length of the exposed portion of the right and left portal veins was measured when the bifurcation was extrahepatic. Results: The portal vein bifurcation was intrahepatic in 37 cadavers (53%) and extrahepatic in 33 cadavers (47%). The mean length of the right and left extrahepatic portal veins was 0.96 cm and 0.85 cm respectively.Both were less than or equal to 2 cm in 94% of the cadavers with extrahepatic bifurcation. There was no correlation between the presence of cirrhosis and the location of the portal vein bifurcation(p 1.0). There was no statistically significant difference in liver mass in cadavers with either extrahepatic or intrahepatic bifurcation (p =0.40). Conclusions: These findings suggest that fortransjugular intrahepatic portosystemic shunt placement, a portal vein puncture 2 cm from the bifurcation will be safe in most cases

The application of TIPSS in portal vein cancerous thrombosis complicated with portal hypertension

International Nuclear Information System (INIS)

Jiang Zaibo; Shan Hong; Guan Shouhai; Zhu Kangshun; Huang Mingsheng; Li Zhengran; Zhu Wenke; Liu Lang; Guo Tiansheng

2002-01-01

Objective: To discuss the technical skills and the contraindication of trans-jugular intrahepatic portosystemic shunt stent (TIPSS) in portal vein cancerous thrombosis (PVCT) complicated with portal hypertension. Methods: There were 16 cases of PVCT with portal hypertension, and average age of 53.6 yr. There were 9 cases with complete occlusion of portal vein trunk and 7 cases with incomplete thrombosis. There were 5 cases with cavernous transformation of the portal vein (CTPV). 1 case of simple upper gastro-intestinal tract (GIT) massive bleeding, 4 with refractory ascites and 11 with upper GIT massive bleeding and refractory ascites. Results: The procedure of TIPS was successful in 11 cases, the successful rate reached about 68.8%. The mean portal vein pressure was reduced from 4.9 kPa to 2.4 kPa with average 2. 5 kPa reduction. Ascites decreased, bleeding stopped and the clinical symptoms disappeared. The average survival period was 136 days. The procedure failed in 5 cases. Conclusions: TIPSS is an effective method to control the bleeding and ascites caused by PVCT. The PV cavernous transformation was the contraindication of TIPSS

Leptomeningeal collateralization in acute ischemic stroke: Impact on prominent cortical veins in susceptibility-weighted imaging

International Nuclear Information System (INIS)

Verma, Rajeev K.; Hsieh, Kety; Gratz, Pascal P.; Schankath, Adrian C.; Mordasini, Pasquale; Zubler, Christoph; Kellner-Weldon, Frauke; Jung, Simon; Schroth, Gerhard; Gralla, Jan; El-Koussy, Marwan

2014-01-01

Background: The extent of hypoperfusion is an important prognostic factor in acute ischemic stroke. Previous studies have postulated that the extent of prominent cortical veins (PCV) on susceptibility-weighted imaging (SWI) reflects the extent of hypoperfusion. Our aim was to investigate, whether there is an association between PCV and the grade of leptomeningeal arterial collateralization in acute ischemic stroke. In addition, we analyzed the correlation between SWI and perfusion-MRI findings. Methods: 33 patients with acute ischemic stroke due to a thromboembolic M1-segment occlusion underwent MRI followed by digital subtraction angiography (DSA) and were subdivided into two groups with very good to good and moderate to no leptomeningeal collaterals according to the DSA. The extent of PCV on SWI, diffusion restriction (DR) on diffusion-weighted imaging (DWI) and prolonged mean transit time (MTT) on perfusion-imaging were graded according to the Alberta Stroke Program Early CT Score (ASPECTS). The National Institutes of Health Stroke Scale (NIHSS) scores at admission and the time between symptom onset and MRI were documented. Results: 20 patients showed very good to good and 13 patients poor to no collateralization. PCV-ASPECTS was significantly higher for cases with good leptomeningeal collaterals versus those with poor leptomeningeal collaterals (mean 4.1 versus 2.69; p = 0.039). MTT-ASPECTS was significantly lower than PCV-ASPECTS in all 33 patients (mean 1.0 versus 3.5; p < 0.00). Conclusions: In our small study the grade of leptomeningeal collateralization correlates with the extent of PCV in SWI in acute ischemic stroke, due to the deoxyhemoglobin to oxyhemoglobin ratio. Consequently, extensive PCV correlate with poor leptomeningeal collateralization while less pronounced PCV correlate with good leptomeningeal collateralization. Further SWI is a very helpful tool in detecting tissue at risk but cannot replace PWI since MTT detects significantly more ill

A protective role of early collateral blood flow in patients with ST-segment elevation myocardial infarction.

Science.gov (United States)

Kim, Eun Kyoung; Choi, Jin-Ho; Song, Young Bin; Hahn, Joo-Yong; Chang, Sung-A; Park, Sung-Ji; Lee, Sang-Chol; Choi, Seung-Hyuk; Choe, Yeon Hyeon; Park, Seung Woo; Gwon, Hyeon-Cheol

2016-01-01

Conflict persists regarding whether the presence of early collateral blood flow to the infarct-related artery has an effective role in reducing infarct size and improving myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI). We sought to investigate the impact of the collateral circulation on myocardial salvage and infarct size in STEMI patients. In 306 patients who were diagnosed with STEMI and underwent cardiac magnetic resonance within 1 week after revascularization, initial collateral flow to the infarct-related artery was assessed by coronary angiography. Using cardiac magnetic resonance imaging, myocardial infarct size and salvage were measured. Among 247 patients with preprocedural Thrombolysis in Myocardial Infarction flow 0/1, 54 (22%) patients had good collaterals (Rentrop grade ≥ 2, Collateral Connection Score ≥ 2). Infarct size and area at risk were significantly smaller in patients with good collaterals than those with poor collaterals (infarct size: 17.1 ± 10.1 %LV vs 21.8 ± 10.5 %LV, P = .003, area at risk: 33.8 ± 16.8 %LV vs 38.8 ± 15.5 %LV, P = .039). There was a significant difference of myocardial salvage index between 2 groups (50.9% ± 15.0% vs 43.8% ± 18.5%, P = .005). Poor collateralization was an independent predictor for large infarct size (odd ratio 2.48 [1.28-4.80], P = .007). In patients with STEMI, the presence of well-developed collaterals to occluded coronary artery from the noninfarct vessel and its extent were independently associated with reduced infarct burden and improved myocardial salvage. Our results help explain why MI patients with well-developed collateralization have reduced mortality and morbidity. Copyright © 2015 Elsevier Inc. All rights reserved.

The NOAO NVO Portal

Science.gov (United States)

Miller, C. J.; Gasson, D.; Fuentes, E.

2007-10-01

The NOAO NVO Portal is a web application for one-stop discovery, analysis, and access to VO-compliant imaging data and services. The current release allows for GUI-based discovery of nearly a half million images from archives such as the NOAO Science Archive, the Hubble Space Telescope WFPC2 and ACS instruments, XMM-Newton, Chandra, and ESO's INT Wide-Field Survey, among others. The NOAO Portal allows users to view image metadata, footprint wire-frames, FITS image previews, and provides one-click access to science quality imaging data throughout the entire sky via the Firefox web browser (i.e., no applet or code to download). Users can stage images from multiple archives at the NOAO NVO Portal for quick and easy bulk downloads. The NOAO NVO Portal also provides simplified and direct access to VO analysis services, such as the WESIX catalog generation service. We highlight the features of the NOAO NVO Portal (http://nvo.noao.edu).

Innate collateral segments are predominantly present in the subendocardium without preferential connectivity within the left ventricular wall

Science.gov (United States)

van Horssen, Pepijn; Siebes, Maria; Spaan, Jos A E; Hoefer, Imo E; van den Wijngaard, Jeroen P H M

2014-01-01

Functional collateral vessels often stem from outward remodelling of pre-existing connections between perfusion territories. Knowledge of the distribution and morphology of innate collateral connections may help in identifying myocardial areas with protection against risk for ischaemia. The coronary network of six healthy canine hearts was investigated with an imaging cryomicrotome. Innate collateral connections ranged from 286 to 1015 μm in diameter. Left ventricular collateral density (number per gram of tissue) was about five in the subendocardium vs. 2.5 in the mid-myocardium (P collateral connections were oriented parallel to the long axis of the heart. For the major coronary arteries, five times more intracoronary than intercoronary connections were found, while their median diameter and interquartile range were not significantly different, at 96.1 (16.9) vs. 94.7 (18.9) μm. Collateral vessels connecting crowns from sister branches from a stem are denoted intercrown connections and those within crowns intracrown connections. The number of intercrown connections was related to the mean tissue weight of the crowns (y = 0.73x − 0.33, r2 = 0.85, P collateral diameter and length were independent of the tissue volumes bridged. We conclude that connectivity and morphology of the innate collateral network are distributed with no preference for intra-or intercrown connections, independent of stem diameter, including epicardial arteries. This renders all sites of the myocardium equally protected in case of coronary artery disease. The orientation of subendocardial collateral vessels indicates the longitudinal direction of subendocardial collateral flow. PMID:24366260

Innate collateral segments are predominantly present in the subendocardium without preferential connectivity within the left ventricular wall.

Science.gov (United States)

van Horssen, Pepijn; Siebes, Maria; Spaan, Jos A E; Hoefer, Imo E; van den Wijngaard, Jeroen P H M

2014-03-01

Functional collateral vessels often stem from outward remodelling of pre-existing connections between perfusion territories. Knowledge of the distribution and morphology of innate collateral connections may help in identifying myocardial areas with protection against risk for ischaemia. The coronary network of six healthy canine hearts was investigated with an imaging cryomicrotome. Innate collateral connections ranged from 286 to 1015 μm in diameter. Left ventricular collateral density (number per gram of tissue) was about five in the subendocardium vs. 2.5 in the mid-myocardium (P collateral connections were oriented parallel to the long axis of the heart. For the major coronary arteries, five times more intracoronary than intercoronary connections were found, while their median diameter and interquartile range were not significantly different, at 96.1 (16.9) vs. 94.7 (18.9) μm. Collateral vessels connecting crowns from sister branches from a stem are denoted intercrown connections and those within crowns intracrown connections. The number of intercrown connections was related to the mean tissue weight of the crowns (y = 0.73x - 0.33, r2 = 0.85, P collateral diameter and length were independent of the tissue volumes bridged. We conclude that connectivity and morphology of the innate collateral network are distributed with no preference for intra- or intercrown connections, independent of stem diameter, including epicardial arteries. This renders all sites of the myocardium equally protected in case of coronary artery disease. The orientation of subendocardial collateral vessels indicates the longitudinal direction of subendocardial collateral flow.

Why is coronary collateral growth impaired in type II diabetes and the metabolic syndrome?

Science.gov (United States)

Rocic, Petra

2012-01-01

Type II diabetes and the metabolic syndrome are strong predictors of severity of occlusive coronary disease and poorer outcomes of coronary revascularization therapies. Coronary collateral growth can provide an alternative or accessory pathway of revascularization. However, collateral growth is impaired in type II diabetes and the metabolic syndrome. Although many factors necessary for collateral growth are known and many interventions have shown promising results in animal studies, not a single attempt to induce coronary collateral growth in human clinical trials has led to satisfactory results. Accordingly, the first part of this review outlines the known deleterious effects of diabetes and the metabolic syndrome on factors necessary for collateral growth, including pro-angiogenic growth factors, endothelial function, the redox state of the coronary circulation, intracellular signaling, leukocytes and bone marrow-derived progenitors cells. The second section highlights the gaps in our current knowledge of how these factors interact with the radically altered environment of the coronary circulation in diabetes and the metabolic syndrome. The interplay between these pathologies and inadequately explored areas related to the temporal regulation of collateral remodeling and the roles of the extracellular matrix, vascular cell phenotype and pro-inflammatory cytokines are emphasized with implications to development of efficient therapies. PMID:22342811

An elevated level of BNP in plasma is related to the development of good collateral circulation in coronary artery disease.

Science.gov (United States)

Xi, Wei-Wei; Cheng, Gang; Lv, Shumin; Gao, Qinqin; Bu, Gang; Zhou, Ying; Xu, Geng

2011-12-01

B-type natriuretic peptide (BNP) was recently demonstrated to be a potential stimulator of angiogenesis and arteriogenesis. The correlation between BNP level and collateral formation in patients with coronary artery disease (CAD) has not been reported. The study included 311 consecutive patients who underwent coronary angiography were divided into three groups according to coronary angiography and collateral formation: normal group (100 patients with normal coronary angiographic findings); poor collateral group (116 patients with at least one coronary stenosis of ≥75% without visible collateral circulation); and good collateral group (95 patients with at least one coronary stenosis of ≥75% with well-developed collateral circulation). Collateral score was analyzed using the Cohen-Rentrop classification. Plasma BNP levels were 45.77 ± 4.66 pg/ml, 116.40 ± 28.15 pg/ml, and 254.20 ± 42.85 pg/ml for patients in normal, poor collateral, and good collateral groups, respectively. Plasma BNP levels in the latter were significantly higher than in the normal group (p collateral group (p collateral group and poor collateral group when compared with left ventricular ejection fraction (LVEF), left ventricular dimensions at end diastole (LVEDd), age, severity of angiographic disease, and other cardiovascular risk factors. After adjustment in the multiple ordinal logistic regression model, plasma BNP levels showed a strong independent association with collateral Cohen-Rentrop score (χ(2 )= 5.636, OR = 1.002, 95% CI 1.000-1.004, p = 0.018). An elevated level of BNP in plasma is independently associated with collateral development; patients with good collaterals tend to have a higher BNP level.

CT portography by multidetector helical CT. Comparison of three rendering models

International Nuclear Information System (INIS)

Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki

2002-01-01

The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

CT portography by multidetector helical CT. Comparison of three rendering models

Energy Technology Data Exchange (ETDEWEB)

Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki [Kumamoto Univ. (Japan). School of Medicine

2002-12-01

The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

Collateral Ligament Knee Injuries in Pediatric and Adolescent Athletes.

Science.gov (United States)

Kramer, Dennis E; Miller, Patricia E; Berrahou, Iman K; Yen, Yi-Meng; Heyworth, Benton E

2017-12-08

The majority of research on medial (MCL) and lateral (LCL) collateral ligament injuries has focused on adults and combined collateral/cruciate injuries. The purpose of this study was to determine characteristics associated with isolated collateral ligament injuries in adolescents, and assess timing for return to sports. Electronic medical records were queried to identify patients aged below 17 years who sustained a magnetic resonance imaging-confirmed isolated MCL or LCL injury over an 8-year period. Retrospective review then documented patient and injury characteristics and clinical course. General linear modeling was used to analyze risk factors for prolonged return to sports, continued pain or reinjury. Fifty-one knees (33 in males, 65%), mean age 13.8 years (range, 5 to 17), were identified, of which 40 (78%) had MCL injuries. Over half (29, 57%) of knees had an open distal femoral physis including all 5 bony avulsion injuries. Eleven (22%) had LCL injuries of which 3 (6%) had concurrent posterolateral corner injuries. Forty-two (82%) knees had injuries that occurred during sports. Eleven knees (28%) with MCL tears had a simultaneous patellar instability episode. Knee injuries that occurred during sports had 37% shorter recovery time (P=0.02). Eight knees (16%) experienced a reinjury and 12 (24%) were followed over an extended period of time for various knee issues. Football injuries were more likely to be grade 3 (P=0.03), and football and soccer accounted for all grade III injuries. The mean return to sports was 2.2 months, with grade III cases returning at 2.4 months, and 95% of cases within 4 months. Isolated collateral ligament injuries are rare in adolescent athletes. MCL injuries, one-quarter of which occurred in conjunction with patellar instability events, were 4 times more common than LCL injuries, one quarter of which have other posterolateral corner structures involved. Grade III injuries represent 20% to 25% of collateral ligament injuries and

Tl myocardial SPECT demonstrates importance of collateral circulation in patients with myocardial infarction

International Nuclear Information System (INIS)

Hattori, Fukunori

1997-01-01

The influence of collateral circulation on the preservation of myocardial viability and the efficacy of drug therapy and PTCA were evaluated by exercise 201 Tl myocardial SPECT before and after treatment. Thirty-five patients with a history of myocardial infarction resulting from total or subtotal obstruction of the responsible coronary artery were divided into four groups, according to the method of the treatment and the degree of collateral blood flow. Patients in groups A and B received drug therapy and displayed developed and undeveloped collateral circulation, respectively. Groups C and D received PTCA and displayed developed and undeveloped collateral circulation, respectively. Tl myocardial SPECT was performed before treatment to record the extent of redistribution to the occluded region, the degree of myocardial viability and the nature and extent of the ischemic lesion. In group A, myocardial perfusion improved, although redistribution remained in all cases, while in group B, 4 of 7 cases improved after drug therapy. In group C, myocardial perfusion improved in all cases, and redistribution disappeared in 7 of 12 cases. 5 of 6 cases improved in group D after PTCA. After drug therapy, the %Tl uptake in the infarcted region improved significantly in initial and delayed images of patients in group A. The differences in initial and delayed images in group B before and after drug therapy were not significant. In contrast, groups C and D both registered significant improvement in initial and delayed images after PTCA. The washout rate improved significantly in groups A, C and D after their respective treatments. These results suggest that developed collateral circulation helps to preserve myocardial viability in cases of myocardial infarction. Myocardial perfusion improved after drug therapy in cases with developed collateral circulation, and in patients with developed and undeveloped collateral circulation receiving PTCA. (K.H.)

31 CFR 202.6 - Collateral security.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collateral security. 202.6 Section 202.6 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE DEPOSITARIES AND FINANCIAL AGENTS OF THE FEDERAL...

12 CFR 614.4240 - Collateral definitions.

Science.gov (United States)

2010-01-01

... following definitions shall apply: (a) Abundance of caution, when used to describe decisions to require... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact... normal consideration for the property sold unaffected by special or creative financing or sales...

Toxic shock syndrome due to community-acquired methicillin-resistant Staphylococcus aureus infection: Two case reports and a literature review in Japan

OpenAIRE

Sada, Ryuichi; Fukuda, Saori; Ishimaru, Hiroyasu

2017-01-01

Community-acquired methicillin-resistant Staphylococcus aureus has been spreading worldwide, including in Japan. However, few cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus have been reported in Japan. We report 2 cases, in middle-aged women, of toxic shock syndrome due to Community-acquired methicillin-resistant Staphylococcus aureus via a vaginal portal of entry. The first patient had used a tampon and the second patient had vaginitis ...

Decision-making models in the analysis of portal films: a clinical pilot study

International Nuclear Information System (INIS)

See, A.; Johansen, J.; Hamilton, C.; Bydder, S.A.; Hawkins, J.; Roff, M.; Denham, J.; Kron, T.

2000-01-01

Portal films continue to play an important role in the verification of radiotherapy treatment. There is still some discussion, however, as to what action should be taken after a port film has shown a radiation field deviation from the prescribed volume. It was the aim of the present pilot study to investigate the performance of three decision-making models ('Amsterdam', 'Quebec' and 'Newcastle') and an expert panel basing their decision on intuition rather than formal rules after portal film acquisition in a clinical setting. Portal films were acquired on every day during the first week of treatment for five head and neck and five prostate cancer patients (diagnostic phase). If required, the field position was modified according to our normal practice following the recommendation of the expert panel. In order to analyse the results of the models, however, additional port films were taken in the following 3 treatment weeks with the patient moved as required by the different models (intervention phase). The portal films were taken over 4 consecutive days, positioning the patient according to each of the different models on one day each. None of the models diagnosed a field misplacement in the head and neck patients, while the 'Amsterdam' and 'Quebec' models predicted a move in one prostate patient. The 'Newcastle' model, which is based on Hotelling's T 2 statistic, proved to be more sensitive and diagnosed a systematic displacement for three prostate patients. The intervention phase confirmed the diagnosis of the model, even if the three portal films taken with the patient position adjusted as required by the model proved to be insufficient to demonstrate an improvement. The 'Newcastle' model does not rely on assumptions about the random movement of patients and requires five portal films before a decision can be reached. This approach lends itself well to incorporation into electronic portal imaging 'packages', where repeated image acquisitions present no logistical

Breast varices: imaging findings of an unusual presentation of collateral pathways in superior vena caval syndrome

International Nuclear Information System (INIS)

Oezdemir, Ayseguel; Ilgit, Erhan T.; Konus, Oeznur L.; Cetin, Meltem; Oezsunar, Yelda

2000-01-01

Imaging findings are presented of an unusual pathway of collateral circulation consisting of bilateral and diffuse dilated breast veins from a patient with long standing superior vena caval syndrome. The main importance of this case is the extent of the collateral development through the breast veins, serving as the major pathway of collateral circulation. Identification of this unusual collateral development, which resembles breast varices, was performed with contrast-enhanced chest CT scans, digital subtraction venography, color Doppler ultrasonography, and mammographic studies. Collateral development was secondary to a long segment idiopathic venous occlusion involving bilateral subclavian and brachiocephalic veins as well as vena cava superior. We conclude that dilated breast veins when detected on any imaging modality should raise the suspicion of central venous obstruction

Influence of oxidative stress on the development of collateral circulation in total coronary occlusions.

Science.gov (United States)

Demirbag, Recep; Gur, Mustafa; Yilmaz, Remzi; Kunt, Alper Sami; Erel, Ozcan; Andac, M Halit

2007-03-02

The purpose of this study was to investigate whether the levels of total antioxidant capacity (TAC), total peroxide and oxidative stress index (OSI) are associated with the development of collaterals in total coronary occlusions. Our study group contained 176 consecutive men patients with single-vessel TCO, 94 of whom had poorly developed coronary collateral, while 82 had well-developed coronary collateral. TAC and total peroxide concentration were measured of plasma. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress. The values of total peroxide and OSI in the Group I were significantly lower than that in Group II (ptotal peroxide and OSI levels (ptotal peroxide and OSI were independent predictors of collaterals score (p=0.006 and ptotal coronary occlusion patients.

Sonographic detection of portal venous gas

International Nuclear Information System (INIS)

Lee, Wang Yul; Lee, S. K.; Cho, O. K.

1989-01-01

Portal venous gas suggests underlying bowel disease such as strangulating intestinal obstruction and its demonstration carries with it an important implications with respect to patient management. Radiography has been the gold standard for the detection of portal venous gas. We have experienced two cases of portal venous gas diagnosed by ultrasound. Sonographic findings were floating echoes in the main portal vein and highly echogenic linear or patchy echoes within the hepatic parenchyma. Simple abdominal films of those cases failed to demonstrate gas in the portal venous system

Usability of Discovery Portals

OpenAIRE

Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.

2013-01-01

As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals are not spatial data experts but professionals with limited spatial knowledge, and a focus outside the spatial domain. An exploratory usability experiment was carried out in which three discovery p...

Severe Degeneration of the Medial Collateral Ligament in Hallux Valgus: A Histopathologic Study in 12 Consecutive Patients

Science.gov (United States)

Prasitdumrong, Ittipol; Rungprai, Chamnanni; Reeboonlarb, Nitit; Poonpracha, Tara; Phisitkul, Phinit

2013-01-01

Objective To determine the degree and location of degenerative changes of the medial collateral ligament of the first metatarsophalangeal joint, using the lateral collateral ligament as a control, in patients undergoing hallux valgus correction. Materials and Methods A strip of medial and lateral collateral ligaments were biopsied from 12 consecutive patients (age 45 ± 4.8 years) with symptomatic hallux valgus. A blinded analysis of histopathology was performed by an experienced pathologist. Results The medial collateral ligament was significantly more degenerated compared to the lateral collateral ligament (x2 = 23.41, DF = 2, p hallux valgus correction. The Authors received no financial support for this study. PMID:24027461

Selective cyclooxygenase-1 inhibition improves collateral vascular reactivity in biliary cirrhotic rats

Directory of Open Access Journals (Sweden)

Ching-Chih Chang

2013-10-01

Conclusion: There was no significant hemodynamic change and renal toxicity after acute administration of COX inhibitor in the FBDL-induced cirrhotic rats. Preincubation of selective COX-1, but not COX-2, inhibitor could enhance collateral vascular response to AVP, indicating that COX-1 plays a major role in the collateral vascular reactivity.

Duplex sonography in portal hypertension

International Nuclear Information System (INIS)

Kwon, Hyuk Po; Jang, J. C.; Park, B. H.

1990-01-01

We measure the diameter and blood velocity of the portal vein in 50 patients with cirrhosis of the liver and 40 healthy subjects, and calculated cross sectional area, mean blood flow velocity, blood flow volume and congestion index. In patients with cirrhosis of the liver, the cross sectional area of the portal vein was significantly increased: the mean blood flow volume was significantly reduced; the blood flow volume was significantly increased; the congestion index of the portal vein was significantly increased. Duples sonography may play an important role in the diagnosis of portal hypertension

Percutaneous transhepatic portal vein stenting in a patient with benign non-transplant postoperative portal vein stenosis: A case report

OpenAIRE

Madhusudhan, KS; Agrawal, Nikhil; Srivastava, Deep N; Pal, Sujoy; Gupta, Arun K

2013-01-01

Extrahepatic portal vein stenosis is caused by a variety of benign and malignant diseases and results in development of symptoms due to portal hypertension. Benign post-surgical adhesions causing portal vein stenosis in non-transplant population is an uncommon etiology of portal hypertension. Endovascular treatment of such patients with angioplasty and stenting is uncommonly reported in literature. We report a case of portal hypertension caused by benign postoperative portal vein fibrosis, su...

Quantitative vs. subjective portal verification using digital portal images.

Science.gov (United States)

Bissett, R; Leszczynski, K; Loose, S; Boyko, S; Dunscombe, P

1996-01-15

Off-line, computer-aided prescription (simulator) and treatment (portal) image registration using chamfer matching has been implemented on PC based viewing station. The purposes of this study were (a) to evaluate the performance of interactive anatomy and field edge extraction and subsequent registration, and (b) to compare observer's perceptions of field accuracy with measured discrepancies following anatomical registration. Prescription-treatment image pairs for 48 different patients were examined in this study. Digital prescription images were produced with the aid of a television camera and a digital frame grabber, while the treatment images were obtained directly from an on-line portal imaging system. To facilitate perception of low contrast anatomical detail, on-line portal images were enhanced with selective adaptive histogram equalization prior to extraction of anatomical edges. Following interactive extraction of anatomical and field border information by an experienced observer, the identified anatomy was registered using chamfer matching. The degree of conformity between the prescription and treatment fields was quantified using several parameters, which included relative prescription field coverage and overcoverage, as well as the translational and rotational displacements as measured by chamfer matching applied to the boundaries of the two fields. These quantitative measures were compared with subjective evaluations made by four radiation oncologists. All the images in this series that included a range of the most commonly seen treatment sites were registered and the conformity parameters were found. The mean treatment/prescription field coverage and overcoverage were approximately 95 and 7%, respectively before registration. The mean translational displacement in the transverse and cranio-caudal directions were 2.9 and 3.4 mm, respectively. The mean rotational displacement was approximately 2 degrees. For all four oncologists, the portals classified

Stimulation of collateral artery growth: travelling further down the road to clinical application

NARCIS (Netherlands)

Schirmer, S. H.; van Nooijen, F. C.; Piek, J. J.; van Royen, N.

2009-01-01

Collateral artery growth is a potent natural defence mechanism to prevent death and myocardial infarction in occlusive artery disease. Given the high prevalence of arterial obstructive disease, a therapeutic compound stimulating collateral vessel growth could have a major impact on morbidity and

SU-F-T-262: Commissioning Varian Portal Dosimetry for EPID-Based Patient Specific QA in a Non-Aria Environment

Energy Technology Data Exchange (ETDEWEB)

Schmidt, M; Knutson, N [Rhode Island Hospital, Providence RI (United States); University of Rhode Island, Kingston, RI (United States); University of Massachusetts Lowell, Lowell, MA (United States); Herrington, J [University of Rhode Island, Kingston, RI (United States); Price, M [Rhode Island Hospital, Providence RI (United States); University of Rhode Island, Kingston, RI (United States); Alpert Medical School of Brown University, Providence, RI (United States)

2016-06-15

Purpose: Development of an in-house program facilitates a workflow that allows Electronic Portal Imaging Device (EPID) patient specific quality assurance (QA) measurements to be acquired and analyzed in the Portal Dosimetry Application (Varian Medical Systems, Palo Alto, CA) using a non-Aria Record and Verify (R&V) system (MOSAIQ, Elekta, Crawley, UK) to deliver beams in standard clinical treatment mode. Methods: Initial calibration of an in-house software tool includes characterization of EPID dosimetry parameters by importing DICOM images of varying delivered MUs to determine linear mapping factors in order to convert image pixel values to Varian-defined Calibrated Units (CU). Using this information, the Portal Dose Image Prediction (PDIP) algorithm was commissioned by converting images of various field sizes to output factors using the Eclipse Scripting Application Programming Interface (ESAPI) and converting a delivered configuration fluence to absolute dose units. To verify the algorithm configuration, an integrated image was acquired, exported directly from the R&V client, automatically converted to a compatible, calibrated dosimetric image, and compared to a PDIP calculated image using Varian’s Portal Dosimetry Application. Results: For two C-Series and one TrueBeam Varian linear accelerators, gamma comparisons (global 3% / 3mm) of PDIP algorithm predicted dosimetric images and images converted via the inhouse system demonstrated agreement for ≥99% of all pixels, exceeding vendor-recommended commissioning guidelines. Conclusion: Combinations of a programmatic image conversion tool and ESAPI allow for an efficient and accurate method of patient IMRT QA incorporating a 3rd party R&V system.

Strategi Branding Portal Online Www.tripriau.com Dalam Membangun Brand Awareness Sebagai Portal Online Pariwisata Provinsi Riau

OpenAIRE

Rahmadhani, Yuri; Lubis, Evawani Elysa

2017-01-01

Online portal www.tripriau.com online portal is one of the online portal in Riau Province that has its own uniqueness. These portals contain local content and the potential of tourism in the province of Riau. Since its establishment, www.tripriau.com do branding strategy in order to build brand awareness or trust the reader to be known as a tourism-themed online portal. As the selection of brand name Trip Riau, Riau Guide My tagline, as well as the implementation of travel instagram photo con...

The Sydney West Knowledge Portal: Evaluating the Growth of a Knowledge Portal to Support Translational Research.