Extrapolation of vertical target motion through a brief visual occlusion.

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Zago, Myrka; Iosa, Marco; Maffei, Vincenzo; Lacquaniti, Francesco

2010-03-01

It is known that arbitrary target accelerations along the horizontal generally are extrapolated much less accurately than target speed through a visual occlusion. The extent to which vertical accelerations can be extrapolated through an occlusion is much less understood. Here, we presented a virtual target rapidly descending on a blank screen with different motion laws. The target accelerated under gravity (1g), decelerated under reversed gravity (-1g), or moved at constant speed (0g). Probability of each type of acceleration differed across experiments: one acceleration at a time, or two to three different accelerations randomly intermingled could be presented. After a given viewing period, the target disappeared for a brief, variable period until arrival (occluded trials) or it remained visible throughout (visible trials). Subjects were asked to press a button when the target arrived at destination. We found that, in visible trials, the average performance with 1g targets could be better or worse than that with 0g targets depending on the acceleration probability, and both were always superior to the performance with -1g targets. By contrast, the average performance with 1g targets was always superior to that with 0g and -1g targets in occluded trials. Moreover, the response times of 1g trials tended to approach the ideal value with practice in occluded protocols. To gain insight into the mechanisms of extrapolation, we modeled the response timing based on different types of threshold models. We found that occlusion was accompanied by an adaptation of model parameters (threshold time and central processing time) in a direction that suggests a strategy oriented to the interception of 1g targets at the expense of the interception of the other types of tested targets. We argue that the prediction of occluded vertical motion may incorporate an expectation of gravity effects.

Deep venous thrombophlebitis following aortoiliac reconstructive surgery

International Nuclear Information System (INIS)

Reilly, M.K.; McCabe, C.J.; Abbott, W.M.; Brewster, D.C.; Moncure, A.C.; Reidy, N.C.; Darling, R.C.

1982-01-01

One hundred patients undergoing elective aortic surgery were scanned prospectively for development of deep venous thrombosis (DVT). The incidence of DVT in this population was 13%. Eleven patients showed only calf vein thrombosis on venography, whereas two had occlusive iliofemoral thrombus. The correlation between venous Doppler ultrasound and venography was 80%. More importantly, Doppler examination correctly identified both patients with occlusive thrombus. Fibrinogen scanning was associated with a false-positive rate of 31%. Only one patient suffered a nonfatal pulmonary embolus. Fibrinogen scanning has an unacceptably high false-positive rate; however, Doppler ultrasound will identify significant occlusive thrombus without a high false-positive rate. The low incidence of pulmonary emboli does not warrant such definitive measures as prophylactic vena caval interruption

Imaging Characteristics of Venous Parenchymal Abnormalities.

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Arnoux, Audrey; Triquenot-Bagan, Aude; Andriuta, Daniela; Wallon, David; Guegan-Massardier, Evelyne; Leclercq, Claire; Martinaud, Olivier; Castier-Amouyel, Mélody; Godefroy, Olivier; Bugnicourt, Jean-Marc

2017-12-01

There are few published data on the patterns of parenchymal imaging abnormalities in a context of cerebral venous thrombosis (CVT). The objectives of the present study were to describe the patterns of parenchymal lesions associated with CVT and to determine the lesion sites. We included 44 consecutively hospitalized patients with CVT and parenchymal lesions on magnetic resonance imaging. The diagnosis of CVT had been confirmed by magnetic resonance imaging/magnetic resonance venography. Magnetic resonance imaging patterns for CVT were retrospectively analyzed with regard to the lesion's type, shape, and site. The most frequent stroke subtype was hemorrhagic ischemia (in 56.8% of cases), followed by intracerebral hematoma (in 22.72% of cases) and nonhemorrhagic ischemia (in 20.45% of cases). Although there were no significant differences between these 3 groups with regard to the clinical and radiological characteristics, we observed a nonsignificant trend ( P =0.08) toward a shorter time interval between hospital admission and magnetic resonance imaging for nonhemorrhagic stroke. The CVT parenchymal abnormalities were centered on 6 main foci and were related to the site of venous occlusion: (1) the inferior parietal lobule (n=20; 44.5%), associated mainly with occlusion of the transverse sinus (n=10) or pure cortical veins (n=10); (2) the inferior and posterior temporal regions (n=10; 22.75%), associated mainly with occlusion of the transverse sinus (n=9); (3) the parasagittal frontal region (n=6; 13.6%), associated mainly with occlusion of the superior sagittal sinus (n=4) or the transverse sinus (n=4); (4) the thalamus (n=5; 11.3%) associated with occlusion of the straight sinus (n=5); (5) the cerebellar hemisphere (n=2; 4.5%), associated in both cases with occlusion of the transverse sinus; and (6) the deep hemispheric regions (n=3; 6.8%), associated with occlusion of the superior sagittal sinus in all cases. Parenchymal lesions caused by CVT display specific

Catheter Occlusion in Home Infusion: The Influence of Needleless Connector Design on Central Catheter Occlusion.

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Williams, Ann

Thrombotic catheter occlusion is a common complication associated with central venous catheters (CVCs). A wide variety of needleless connectors that differ greatly in design and function are available for use with CVCs; however, there are a limited number of studies comparing the catheter occlusion rate associated with differently designed needleless connectors. This retrospective observational study compared occlusion rates associated with a split-septum neutral-displacement needleless connector versus those of a solid-surface neutral-reflux needleless connector in patients undergoing home infusion therapy. The neutral-reflux needleless connector was associated with a significant reduction in occlusion rate and thrombolytic use versus the neutral-displacement needleless connector.

Altered Venous Function during Long-Duration Spaceflights

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Jacques-Olivier Fortrat

2017-09-01

Full Text Available Aims: Venous adaptation to microgravity, associated with cardiovascular deconditioning, may contribute to orthostatic intolerance following spaceflight. The aim of this study was to analyze the main parameters of venous hemodynamics with long-duration spaceflight.Methods: Venous plethysmography was performed on 24 cosmonauts before, during, and after spaceflights aboard the International Space Station. Venous plethysmography assessed venous filling and emptying functions as well as microvascular filtration, in response to different levels of venous occlusion pressure. Calf volume was assessed using calf circumference measurements.Results: Calf volume decreased during spaceflight from 2.3 ± 0.3 to 1.7 ± 0.2 L (p < 0.001, and recovered after it (2.3 ± 0.3 L. Venous compliance, determined as the relationship between occlusion pressure and the change in venous volume, increased during spaceflight from 0.090 ± 0.005 to 0.120 ± 0.007 (p < 0.01 and recovered 8 days after landing (0.071 ± 0.005, arbitrary units. The index of venous emptying rate decreased during spaceflight from −0.004 ± 0.022 to −0.212 ± 0.033 (p < 0.001, arbitrary units. The index of vascular microfiltration increased during spaceflight from 6.1 ± 1.8 to 10.6 ± 7.9 (p < 0.05, arbitrary units.Conclusion: This study demonstrated that overall venous function is changed during spaceflight. In future, venous function should be considered when developing countermeasures to prevent cardiovascular deconditioning and orthostatic intolerance with long-duration spaceflight.

Incidence of Central Vein Stenosis and Occlusion Following Upper Extremity PICC and Port Placement

International Nuclear Information System (INIS)

Gonsalves, Carin F.; Eschelman, David J.; Sullivan, Kevin L.; DuBois, Nancy; Bonn, Joseph

2003-01-01

The purpose of this study was to determine the incidence of central vein stenosis and occlusion following upper extremity placement of peripherally inserted central venous catheters(PICCs) and venous ports. One hundred fifty-four patients who underwent venography of the ipsilateral central veins prior to initial and subsequent venous access device insertion were retrospectively identified. All follow-up venograms were interpreted at the time of catheter placement by one interventional radiologist over a 5-year period and compared to the findings on initial venography. For patients with central vein abnormalities, hospital and home infusion service records and radiology reports were reviewed to determine catheter dwelltime and potential alternative etiologies of central vein stenosis or occlusion. The effect of catheter caliber and dwell time on development of central vein abnormalities was evaluated. Venography performed prior to initial catheter placement showed that 150 patients had normal central veins. Three patients had central vein stenosis, and one had central vein occlusion. Subsequent venograms (n = 154)at the time of additional venous access device placement demonstrated 8 patients with occlusions and 10 with stenoses. Three of the 18 patients with abnormal follow-up venograms were found to have potential alternative causes of central vein abnormalities. Excluding these 3 patients and the 4 patients with abnormal initial venograms, a 7% incidence of central vein stenosis or occlusion was found in patients with prior indwelling catheters and normal initial venograms. Catheter caliber showed no effect on the subsequent development of central vein abnormalities. Patients who developed new or worsened central vein stenosis or occlusion had significantly (p =0.03) longer catheter dwell times than patients without central vein abnormalities. New central vein stenosis or occlusion occurred in 7% of patients following upper arm placement of venous access devices

Efficacy and safety of using L-cysteine as a catheter-clearing agent for nonthrombotic occlusions of central venous catheters in children.

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Pai, Vinita B; Plogsted, Steven

2014-10-01

Critically ill pediatric patients, especially in the intensive care unit, receive multiple medications and have a higher risk of central venous catheter (CVC) occlusion. If an occlusion occurs immediately after the administration of multiple medications or incompatible medications, either an acidic solution such as 0.1 N hydrochloric acid (HCl) or a basic solution of 1 mEq/mL sodium bicarbonate or 0.1 N sodium hydroxide can be used. However, compounding and storing of 0.1 N HCl has become more complex due to USP guidelines for sterile compounding, and an alternative is needed. We report a series of cases in which L-cysteine was used instead of HCl to clear CVCs occluded due to administration of multiple medications. L-cysteine is a commercially available, sterile solution with a pH of 1–2.5. CVC occlusion was resolved in 10 of the 16 episodes in 13 patients. Two of the 16 occlusions were phenytoin related and would not have responded. An L-cysteine dose of 50 mg was used during 10 of the 16 episodes, 100 mg during 5 episodes, and 25 mg during 1 episode. A correlation between catheter clearance and dose was not observed. Occlusion resolution due to L-cysteine was not correlated to the prior use of tissue plasminogen activator. Metabolic acidosis, adverse effects, or damage to the catheters due to L-cysteine were not observed. On the basis of this limited experience, we propose L-cysteine as an effective alternative to 0.1 N HCl for clearing CVC occlusions caused by drugs with an acidic pKa.

[Complications associated to central venous catheters in hematology patients].

Science.gov (United States)

García-Gabás, Carmen; Castillo-Ayala, Ana; Hinojo-Marín, Begoña; Muriel-Abajo, M Ángeles; Gómez-Gutiérrez, Isabel; de Mena-Arenas, Ana M; Rodríguez-Gonzalo, Ana; Chao-Lozano, Cristina; García-Menéndez, Carmen; Madroñero-Agreda, M Antonia

2015-01-01

To discover the incidence of central venous catheters (tunnelled, subcutaneous and PICC) in patients with onco-hematological conditions, hospitalized in the Hematology or Transplantations of Hematopoietic Stem Cells Units, in two tertiary care hospitals. A cross-sectional, descriptive study form was developed in order to gather sociodemographic, clinical data as well as complications and follow-up of the care protocol. Each catheter was assigned a correlative identification number. Information was collected on 366 catheters: 185 in the University Hospital Ramón y Cajal (HURYC), 80 tunnelled, 40 subcutaneous venous access and 65 PICC, and 181 in the University Hospital Gregorio Marañón (HUGM), 101 tunnelled and 80 subcutaneous venous access. Major complications in the tunnellized were infections (13.7% in HURYC vs. 6.8% in HUGM - p<0.001) and occlusions (at least once in 3.8% vs. 21.8%). In subcutaneous venous access, infections were confirmed in 5% in HURYC vs. 1.2% in HUGM. There were occlusions at least once in 10% in HUGM and no other significant complications were detected. Regarding PICC, information was only collected in HURYC, where complications were phlebitis 10.8%, thrombosis 7.7%, confirmed or suspected infection 4.6%, occlusion at least once 7.7%. Differences between hospitals with regard to major complications, infection and occlusion may be related to different care protocol. We need to stress the high incidence of phlebitis and thrombosis in PICC catheters, compared with data of lower incidence of other papers. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Thrombin Avtivable Fibrinolysis Inhibitor in Venous and Arterial Thrombosis

NARCIS (Netherlands)

E.L.E. de Bruijne

2011-01-01

textabstractVenous and arterial thromboses are major causes of morbidity and mortality. Venous thrombosis is the result of pathological occlusive clot formation in the veins. It occurs mainly in the deep veins of the leg (deep vein thrombosis), from which parts of the clot frequently embolize to the

Veno-occlusive disease of the colon - CT findings

International Nuclear Information System (INIS)

Rademaker, J.

1998-01-01

Venous occlusion is a rare cause of ischemic bowel disease and is usually brought about by thrombosis that may occur as a complication of systemic disorders like systemic lupus erythematosus, Behcet disease or Churg-Strauss syndrome. This report describes a patient with veno-occlusive disease of the colon caused by lymphocytic phlebitis. Typical CT findings included homogeneous bowel wall thickening and vascular engorgement. (orig.) (orig.)

Veno-occlusive disease of the colon - CT findings

Energy Technology Data Exchange (ETDEWEB)

Rademaker, J [Department of Radiology I, Medical School Hannover (Germany)

1998-10-01

Venous occlusion is a rare cause of ischemic bowel disease and is usually brought about by thrombosis that may occur as a complication of systemic disorders like systemic lupus erythematosus, Behcet disease or Churg-Strauss syndrome. This report describes a patient with veno-occlusive disease of the colon caused by lymphocytic phlebitis. Typical CT findings included homogeneous bowel wall thickening and vascular engorgement. (orig.) (orig.) With 1 fig., 4 refs.

Complications of central venous stenosis due to permanent central venous catheters in children on hemodialysis.

Science.gov (United States)

Rinat, Choni; Ben-Shalom, Efrat; Becker-Cohen, Rachel; Feinstein, Sofia; Frishberg, Yaacov

2014-11-01

Central venous catheters are frequently used as access for hemodialysis (HD) in children. One of the known complications is central venous stenosis. Although this complication is not rare, it is often asymptomatic and therefore unacknowledged. Superior vena cava (SVC) stenosis is obviously suspected in the presence of upper body edema, but several other signs and symptoms are often unrecognized as being part of this syndrome. We describe four patients with various manifestations of central venous stenosis and SVC syndrome. These sometimes life- or organ-threatening conditions include obstructive sleep apnea, unresolving stridor, increased intracranial pressure, increased intraocular pressure, right-sided pleural effusion, protein-losing enteropathy and lymphadenopathy. The temporal relationship of these complications associated with the use of central venous catheters and documentation of venous stenosis, together with their resolution after alleviation of high venous pressure, points to a causal role. We suggest pathophysiological mechanisms for the formation of each of these complications. In patients with occlusion of the SVC, various unexpected clinical entities can be caused by high central venous pressure. As often the etiology is not obvious, a high index of suspicion is needed as in some cases prompt alleviation of the high pressure is mandatory.

Case report: Unilateral conduction hearing loss due to central venous occlusion.

Science.gov (United States)

Ribeiro, Phillip; Patel, Swetal; Qazi, Rizwan A

2016-05-07

Central venous stenosis is a well-known complication in patients with vascular access for hemodialysis. We report two cases involving patients on hemodialysis with arteriovenous fistulas who developed reversible unilateral conductive hearing loss secondary to critical stenosis of central veins draining the arteriovenous dialysis access. A proposed mechanism for the patients' reversible unilateral hearing loss is pterygoid venous plexus congestion leading to decreased Eustachian tube patency. Endovascular therapy was conducted to treat the stenosis and the hearing loss of both patients was returned to near normal after successful central venous angioplasty.

Bilateral retinal vein occlusion and rubeosis irides: lessons to learn.

Science.gov (United States)

Md Noh, Umi Kalthum; Ahem, Amin; Mustapha, Mushawiahti

2013-01-01

Uncontrolled hypertension is well- known to give rise to systemic complications involving multiple central organs. Artherosclerosis leads to damage of the retinal vessels wall, contributing to venous stasis, thrombosis and finally, occlusion. Retinal vein occlusions compromise vision through development of ischaemic maculopathy, macular oedema, and rubeotic glaucoma. Laser photocoagulation remains the definitive treatment for ischaemic vein occlusion with secondary neovascularization. Timely treatment with anti- vascular endothelial growth factor prevents development of rubeotic glaucoma. We hereby report an unusual case of bilateral retinal vein occlusion complicated by rubeosis irides, which was successfully managed to improve vision and prevent rubeotic glaucoma.

Computationally Efficient Automatic Coast Mode Target Tracking Based on Occlusion Awareness in Infrared Images.

Science.gov (United States)

Kim, Sohyun; Jang, Gwang-Il; Kim, Sungho; Kim, Junmo

2018-03-27

This paper proposes the automatic coast mode tracking of centroid trackers for infrared images to overcome the target occlusion status. The centroid tracking method, using only the brightness information of an image, is still widely used in infrared imaging tracking systems because it is difficult to extract meaningful features from infrared images. However, centroid trackers are likely to lose the track because they are highly vulnerable to screened status by the clutter or background. Coast mode, one of the tracking modes, maintains the servo slew rate with the tracking rate right before the loss of track. The proposed automatic coast mode tracking method makes decisions regarding entering coast mode by the prediction of target occlusion and tries to re-lock the target and resume the tracking after blind time. This algorithm comprises three steps. The first step is the prediction process of the occlusion by checking both matters which have target-likelihood brightness and which may screen the target despite different brightness. The second step is the process making inertial tracking commands to the servo. The last step is the process of re-locking a target based on the target modeling of histogram ratio. The effectiveness of the proposed algorithm is addressed by presenting experimental results based on computer simulation with various test imagery sequences compared to published tracking algorithms. The proposed algorithm is tested under a real environment with a naval electro-optical tracking system (EOTS) and airborne EO/IR system.

Computationally Efficient Automatic Coast Mode Target Tracking Based on Occlusion Awareness in Infrared Images

Directory of Open Access Journals (Sweden)

Sohyun Kim

2018-03-01

Full Text Available This paper proposes the automatic coast mode tracking of centroid trackers for infrared images to overcome the target occlusion status. The centroid tracking method, using only the brightness information of an image, is still widely used in infrared imaging tracking systems because it is difficult to extract meaningful features from infrared images. However, centroid trackers are likely to lose the track because they are highly vulnerable to screened status by the clutter or background. Coast mode, one of the tracking modes, maintains the servo slew rate with the tracking rate right before the loss of track. The proposed automatic coast mode tracking method makes decisions regarding entering coast mode by the prediction of target occlusion and tries to re-lock the target and resume the tracking after blind time. This algorithm comprises three steps. The first step is the prediction process of the occlusion by checking both matters which have target-likelihood brightness and which may screen the target despite different brightness. The second step is the process making inertial tracking commands to the servo. The last step is the process of re-locking a target based on the target modeling of histogram ratio. The effectiveness of the proposed algorithm is addressed by presenting experimental results based on computer simulation with various test imagery sequences compared to published tracking algorithms. The proposed algorithm is tested under a real environment with a naval electro-optical tracking system (EOTS and airborne EO/IR system.

Novel experience of laser-assisted 'inside-out' central venous access in a patient with bilateral subclavian vein occlusion requiring pacemaker implantation.

Science.gov (United States)

Aye, Thandar; Phan, Thanh Trung; Muir, Douglas Findlay; Linker, Nicholas John; Hartley, Richard; Turley, Andrew John

2017-10-01

This new laser facilitated 'inside-out' technique was used for transvenous pacemaker insertion in a pacemaker-dependent patient with bilateral subclavian occlusion and a failed epicardial system who is not suitable for a transfemoral approach. Procedure was undertaken under general anaesthesia with venous access obtained from right femoral vein and left axillary vein. 7F multipurpose catheter was used to enter proximal edge of the occluded segment of subclavian vein via femoral approach, which then supported stiff angioplasty wires and microcatheters to tunnel into the body of occlusion. When encountered with impenetrable resistance, 1.4 mm Excimer laser helped delivery of a Pilot 200 wire, which then progressed towards the distal edge of occlusion. Serial balloon dilatations allowed wire tracked into subintimal plane, advanced towards left clavicle using knuckle wire technique, which was then externalized with blunt dissection from infraclavicular pocket area. It was later changed to Amplatz superstiff wire exiting from both ends to form a rail, which ultimately allowed passage of pacing leads after serial balloon dilatation from clavicular end. Our hybrid 'inside-out' technique permitted transvenous pacemaker insertion without complication and this is, to our knowledge, the first case using laser in this context. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Severe Juxtahepatic Venous Injury: Survival after Prolonged Hepatic Vascular Isolation Without Shunting

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J. E. J. Krige

1990-01-01

Full Text Available Survival following major juxtahepatic venous injury is rare in blunt liver trauma despite the use of intracaval shunting. Prolonged liver arterial inflow control, total hepatic venous isolation and lobectomy without shunting was used in a patient to repair a combined vena caval and hepatic venous injury after blunt liver injury. An extended period of normothermic hepatic ischemia was tolerated. Early recognition of retrohepatic venous injury and temporary liver packing to control bleeding and correct hypovolemia are essential before caval occlusion. Hepatic vascular isolation without shunting is an effective simple alternative technique allowing major venous repair in complex liver trauma.

Advantages and disadvantages of peripherally inserted central venous catheters (PICC) compared to other central venous lines: a systematic review of the literature.

Science.gov (United States)

Johansson, Eva; Hammarskjöld, Fredrik; Lundberg, Dag; Arnlind, Marianne Heibert

2013-06-01

The use of central venous lines carries a significant risk for serious complications and high economic costs. Lately, the peripherally inserted central venous catheter (PICC) has gained in popularity due to presumed advantages over other central venous lines. The aim of this systematic literature review was to identify scientific evidence justifying the use of PICC. The literature review was performed according to the principles of Cochrane Collaboration. The electronic literature search included common databases up to March 2011. Only those studies rated as high or moderate quality were used for grading of evidence and conclusions. The search resulted in 827 abstracts, 48 articles were read in full text, and 11 met the inclusion criteria. None of the articles was classified as high quality and two had moderate quality. The results of these two studies indicate that PICC increases the risk for deep venous thrombosis (DVT), but decreases the risk for catheter occlusion. The quality of scientific evidence behind these conclusions, however, was limited. Due to the lack of studies with sufficiently high quality, questions such as early complications, patient satisfaction and costs could not be answered. We conclude that although PICCs are frequently used in oncology, scientific evidence supporting any advantage or disadvantage of PICC when comparing PICC with traditional central venous lines is limited, apart from a tendency towards increased risk for DVT and a decreased risk for catheter occlusion with PICC.

Outflow occlusion for circulatory arrest in dogs "Outfow occlusion" para parada circulatória em cães

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James N.B.M. de Andrade

2009-02-01

Full Text Available The purpose of this study was to evaluate the possibility of producing circulatory arrest by occlusion of the pulmonary trunk as an alternative to the venous inflow occlusion through the left hemithorax. Eight healthy mongrel dogs were divided in two groups. Group I underwent 4 minutes of outflow occlusion and Group II was submitted to 8 minutes of circulatory arrest. Outflow occlusion was performed through left thoracotomy and pericardiotomy by passing a Rumel tourniquet around the pulmonary trunk. Physical examination, electrocardiography, echocardiography, blood gas analyses, hemodynamic, and oxygen transport variables were obtained before and after the procedure. The dogs from Group I did not have any clinical, electrocardiographic, echocardiographic, or hemo-dynamic abnormalities after anesthetic recover. In the Group II, only one dog survived, which had no clinical, electrocardiographic, or echocardiographic abnormalities. In this last dog, just after releasing the occlusion, it was detected increases in the following parameters: heart rate (HR, systolic, diastolic and mean arterial blood pressure (SAP; DAP; MAP, pulmonary artery pressure (PAP, pulmonary wedge pressure (PWP, central venous pressure (CVP, cardiac output (CO, systolic index (SI, cardiac index (CI, left and right ventricular stroke work (LVSW; RVSW, oxygen delivery index (DO2, oxygen consumption index (VO2, and oxygen extraction (O2 ext. Moreover, the oxygen content of arterial and mixed venous blood (CaO2; CvO2, and the arterial and mixed venous partial pressure of oxygen (PaO2; PvO2 were decreased 5 minutes after circulatory arrest. Outflow occlusion is a feasible surgical procedure for period of 4 minutes of circulatory arrest.O objetivo deste estudo foi avaliar a possibilidade de se produzir uma parada circulatória pela oclusão do tronco pulmonar, como alternativa ao "inflow occlusion", pelo hemitórax esquerdo. Oito cães sem raça definida foram divididos em dois

MRI and CT in cerebral venous thrombosis

International Nuclear Information System (INIS)

Surur, Alberto; Marangoni, Alberto; Devallis, Juan P.; Galvez, Vasco; Marchegiani, Silvio; Galletti, Cayetano; Martin, Juan J.

2004-01-01

Purpose: The veno-occlusive encephalic disease is a neurologic disorder of difficult clinic diagnostic almost always. This clinic situation presents a high morbi-mortality range without an early and precise diagnostic. With the use of Helical Computed Tomography (HCT) and Angio Magnetic Resonance Image (AMRI) the diagnosis has became more effective in the encephalic venous thrombosis. Methods: Fourteen patients with clinical suspicion on encephalic venous thrombosis using non-invasive techniques as HCT and AMRI were studied. Results: In all these cases we were able to arrive at the exact etiologic diagnostic using these techniques associated to the clinics findings, without needing the use of another invasive method like Angiography. Conclusion: The results were satisfactory for definitive diagnosis, without Angiography. When a patient has a high suspicion of veno-occlusive disease the neuro radiologic examination in the urgency is a very important fact and using HCT and AMRI as the first examinations techniques it is possible to obtain good results without most aggressive techniques. (author)

Clinical significance of balloon dilatation angiography during cerebral venous sinus stenosis stenting

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Xiang-yu CAO

2016-12-01

Full Text Available Objective To explore the clinical significance of balloon dilatation angiography during cerebral venous sinus stenosis stenting to predict the reflux of perforator veins after operation. Methods A total of 93 patients (including 51 with cerebral venous sinus stenosis and intracranial hypertension and 42 with intractable pulsatile tinnitus caused by cerebral venous sinus stenosis who were treated by stent implantation were analyzed retrospectively. Among those patients, the diameter of transverse and sigmoid sinuses of 63 cases were measured based on angiography, and stent was selected according to the measurement result. The other 30 cases were given angiography on ipsilateral carotid artery or vertebral artery when the balloon was dilated in the venous sinus to confirm the reflux of perforator veins. If the venous reflux decreased in the angiography, stent with diameter 1-2 mm less than that of venous sinus could be selected.  Results The success rate of stenting was 100% (93/93. In 63 cases, 45 cases were planted 9 mm × 40 mm stents, 15 were planted 8 mm × 40 mm stents, 3 were planted 7 mm × 40 mm stents. The average diameter of stents was (8.67 ± 0.68 mm. There were 11 cases (17.46% with slow perforator venous reflux after operation. In the other 30 cases, 3 cases were planted 8 mm × 40 mm stents, 11 were planted 7 mm × 40 mm stents, and 16 were planted 6 mm × 40 mm stents. The average diameter of stents was (7.57 ± 0.67 mm. There was only one case (3.33% with slow perforator venous reflux after operation. The difference of stent diameter between 2 groups was statistically significant (t = 15.632, P = 0.001. The occurrence rate of perforator vein occlusion after operation between 2 groups was significantly different (adjusted χ 2 = 60.065, P = 0.001.  Conclusions Perforator vein occlusion after cerebral venous sinus stenting is common complication. Balloon dilatation angiography could predict the possibility of perforator vein

Endovascular management of deep venous thrombotic diseases of the lower extremity

International Nuclear Information System (INIS)

Roh, Byung Suk

2004-01-01

Pulmonary embolism and venous ischemia are acute complications of deep vein thrombosis (DVT) of the lower extremities. Delayed complications include a spectrum of debilitating symptoms referred to as postthrombotic syndrome (PST). Because the early symptoms and patient signs are nonspecific for DVT, careful history taking and radiological evaluation of the extent and migration of thrombus should be used to establish an objective diagnosis and the need for treatment. Anticoagulation therapy is recognized as the mainstay treatment in acute DVT. However, there are few data to suggest any major beneficial effect of the early clearing of massive DVT and PTS. Endovascular, catheter-directed, thrombolysis techniques, used alone or in combination with mechanical thrombectomy devices, have been proven to be highly effective in clearing acute DVT, which may allow the preservation of venous valve function and the prevention of subsequent venous occlusive disease. Definitive management of the underlying anatomic occlusive abnormalities should also be undertaken

Endovascular management of deep venous thrombotic diseases of the lower extremity

Energy Technology Data Exchange (ETDEWEB)

Roh, Byung Suk [School of Medicine, Wonkwang Univ., Iksan (Korea, Republic of)

2004-07-01

Pulmonary embolism and venous ischemia are acute complications of deep vein thrombosis (DVT) of the lower extremities. Delayed complications include a spectrum of debilitating symptoms referred to as postthrombotic syndrome (PST). Because the early symptoms and patient signs are nonspecific for DVT, careful history taking and radiological evaluation of the extent and migration of thrombus should be used to establish an objective diagnosis and the need for treatment. Anticoagulation therapy is recognized as the mainstay treatment in acute DVT. However, there are few data to suggest any major beneficial effect of the early clearing of massive DVT and PTS. Endovascular, catheter-directed, thrombolysis techniques, used alone or in combination with mechanical thrombectomy devices, have been proven to be highly effective in clearing acute DVT, which may allow the preservation of venous valve function and the prevention of subsequent venous occlusive disease. Definitive management of the underlying anatomic occlusive abnormalities should also be undertaken.

Hepatic veno-occlusive disease associated with comfrey ingestion.

Science.gov (United States)

Yeong, M L; Swinburn, B; Kennedy, M; Nicholson, G

1990-01-01

A 23 year old man presented with hepatic veno-occlusive disease and severe portal hypertension and subsequently died from liver failure. Light microscopy and hepatic angiography showed occlusion of sublobular veins and small venous radicles of the liver, associated with widespread haemorrhagic necrosis of hepatocytes. The patient had been on a predominantly vegetarian diet and, prior to his illness, took comfrey leaves which are known to contain hepatotoxic pyrrolizidine alkaloids. Comfrey is widely used as a herbal remedy, but so far has only been implicated in two other documented cases of human hepatic veno-occlusive disease. A possible causal association of comfrey and this patient's veno-occlusive disease is suggested by the temporal relationship of the ingestion of comfrey to his presentation, the histological changes in the liver and the exclusion of other known causes of the disease.

Pretreatment with remifentanil, fentanyl, or lidocaine to prevent withdrawal after rocuronium using venous occlusion technique in children and adolescents: a prospective randomized placebo-controlled double-blind study.

Science.gov (United States)

Abu-Halaweh, S A; Aloweidi, A K; Qudaisat, I Y; Al-Hussami, M O; Al Zaben, K R; Abu-Halaweh, A S

2014-12-01

Pain caused by intravenous injection of the muscle relaxant rocuronium bromide is common in children and adolescents. The cause of this unwanted effect is still unclear, and different pretreatment drugs have been administered in attempts to alleviate this side effect, with varying degrees of success. This study used a 60-s venous occlusion technique to evaluate the effectiveness of pretreatment with lidocaine, fentanyl, or remifentanil in preventing pain-induced withdrawal caused by intravenous injection of rocuronium bromide during the induction of general anesthesia. One hundred and one child and adolescent patients, ASA Ι-II, requiring various surgical procedures under general anesthesia with muscle relaxation and mechanical ventilation, were enrolled. Patients were allocated randomly using computer-generated randomization into one of four pretreatment groups: a remifentanil group (1 µg/kg, n = 25), fentanyl group (1 µg/kg, n = 26), lidocaine 1% group (0.5 mg/kg, n = 25), and normal saline group (n = 25). Drug doses were prepared in normal saline to a total volume of 5 ml. Venous occlusion was applied 10 cm above the venous access site. Pretreatment drugs were injected and retained for 60 s at the site of injection by an anesthetist blinded to group allocation. After release of the tourniquet, rocuronium (0.5 mg/kg) was then injected over 5 s, and withdrawal was recorded by another anesthetist blinded to group allocation. Descriptive statistics, analysis of variance, and a chi-squared test were used to statistically analyze the results as appropriate. Compared to normal saline, all other pretreatment groups scored a significantly lower mean of withdrawal response (P rocuronium injection. Remifentanil was superior to fentanyl in suppressing the withdrawal response caused by rocuronium injection (P rocuronium injection in children and adolescents. Lidocaine was superior to remifentanil which, in turn, was more effective than fentanyl.

Central venous obstruction in the thorax

International Nuclear Information System (INIS)

Collin, G.; Jones, R.G.; Willis, A.P.

2015-01-01

Central venous stenosis and occlusion can occur secondary to a spectrum of conditions ranging from aggressive malignancy to benign extrinsic anatomical compression in otherwise healthy individuals. Irrespective of aetiology, significant morbidity in the acute setting and long term can occur unless prompt accurate diagnosis and appropriate management is initiated, the radiologist being central to both. The present review will provide radiologists with a thorough illustration and explanation of the range of central venous conditions in the thorax (including deep vein thrombosis, thoracic outlet syndrome, haemodialysis, and malignancy related causes), the salient imaging findings and interventional management using case examples from the authors' practice. - Highlights: • We show a range of causes of central venous disease in the thorax. • We provide information about different imaging and management strategies. • We show several cases with successes and complications of endovascular management

Mesenteric vascular occlusion: Comparison of ancillary CT findings between arterial and venous occlusions and independent CT findings suggesting life-threatening events

International Nuclear Information System (INIS)

Wong, Yon Cheong; Wu, Cheng Hsien; Wang, Li Jen; Chen, Huan Wu; Lin, Being Chuan; Huang, Chen Chih

2013-01-01

To compare the ancillary CT findings between superior mesenteric artery thromboembolism (SMAT) and superior mesenteric vein thrombosis (SMVT), and to determine the independent CT findings of life-threatening mesenteric occlusion. Our study was approved by the institution review board. We included 43 patients (21 SMAT and 22 SMVT between 1999 and 2008) of their median age of 60.0 years, and retrospectively analyzed their CT scans. Medical records were reviewed for demographics, management, surgical pathology diagnosis, and outcome. We compared CT findings between SMAT and SMVT groups. Multivariate analysis was conducted to determine the independent CT findings of life-threatening mesenteric occlusion. Of 43 patients, 24 had life-threatening mesenteric occlusion. Death related to mesenteric occlusion was 32.6%. A thick bowel wall (p < 0.001), mesenteric edema (p < 0.001), and ascites (p = 0.009) were more frequently associated with SMVT, whereas diminished bowel enhancement (p = 0.003) and paralytic ileus (p = 0.039) were more frequent in SMAT. Diminished bowel enhancement (OR = 20; p = 0.007) and paralytic ileus (OR = 16; p = 0.033) were independent findings suggesting life-threatening mesenteric occlusion. The ancillary CT findings occur with different frequencies in SMAT and SMVT. However, the independent findings indicating life-threatening mesenteric occlusion are diminished bowel wall enhancement and paralytic ileus.

Venous leg ulcers

Science.gov (United States)

2008-01-01

Introduction Leg ulcers usually occur secondary to venous reflux or obstruction, but 20% of people with leg ulcers have arterial disease, with or without venous disorders. Between 1.5 and 3.0/1000 people have active leg ulcers. Prevalence increases with age to about 20/1000 in people aged over 80 years. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of standard treatments, adjuvant treatments, and organisational interventions for venous leg ulcers? What are the effects of interventions to prevent recurrence of venous leg ulcers? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 80 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression bandages and stockings, cultured allogenic (single or bilayer) skin replacement, debriding agents, dressings (cellulose, collagen, film, foam, hyaluronic acid-derived, semi-occlusive alginate), hydrocolloid (occlusive) dressings in the presence of compression, intermittent pneumatic compression, intravenous prostaglandin E1, larval therapy, laser treatment (low-level), leg ulcer clinics, multilayer elastic system, multilayer elastomeric (or non-elastomeric) high-compression regimens or bandages, oral treatments (aspirin, flavonoids, pentoxifylline, rutosides, stanozolol, sulodexide, thromboxane alpha2 antagonists, zinc), peri

The role of "rescue saccades" in tracking objects through occlusions.

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Zelinsky, Gregory J; Todor, Andrei

2010-12-29

We hypothesize that our ability to track objects through occlusions is mediated by timely assistance from gaze in the form of "rescue saccades"-eye movements to tracked objects that are in danger of being lost due to impending occlusion. Observers tracked 2-4 target sharks (out of 9) for 20 s as they swam through a rendered 3D underwater scene. Targets were either allowed to enter into occlusions (occlusion trials) or not (no occlusion trials). Tracking accuracy with 2-3 targets was ≥ 92% regardless of target occlusion but dropped to 74% on occlusion trials with four targets (no occlusion trials remained accurate; 83%). This pattern was mirrored in the frequency of rescue saccades. Rescue saccades accompanied approximatlely 50% of the Track 2-3 target occlusions, but only 34% of the Track 4 occlusions. Their frequency also decreased with increasing distance between a target and the nearest other object, suggesting that it is the potential for target confusion that summons a rescue saccade, not occlusion itself. These findings provide evidence for a tracking system that monitors for events that might cause track loss (e.g., occlusions) and requests help from the oculomotor system to resolve these momentary crises. As the number of crises increase with the number of targets, some requests for help go unsatisfied, resulting in degraded tracking.

Transposition of cephalic vein to rescue hemodialysis access arteriovenous fistula and treat symptomatic central venous obstruction

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Felipe Jose Skupien

2014-03-01

Full Text Available It is known that stenosis or central venous obstruction affects 20 to 50% of patients who undergo placement of catheters in central veins. For patients who are given hemodialysis via upper limbs, this problem causes debilitating symptoms and increases the risk of loss of hemodialysis access. We report an atypical case of treatment of a dialysis patient with multiple comorbidities, severe swelling and pain in the right upper limb (RUL, few alternative sites for hemodialysis vascular access, a functioning brachiobasilic fistula in the RUL and severe venous hypertension in the same limb, secondary to central vein occlusion of the internal jugular vein and right brachiocephalic trunk. The alternative surgical treatment chosen was to transpose the RUL cephalic vein, forming a venous necklace at the anterior cervical region, bypassing the site of venous occlusion. In order to achieve this, we dissected the cephalic vein in the right arm to its junction with the axillary vein, devalved the cephalic vein and anastomosed it to the contralateral external jugular vein, providing venous drainage to the RUL, alleviating symptoms of venous hypertension and preserving function of the brachiobasilic fistula.

Pattern of venous collateral development after splenic vein occlusion in an extended Whipple procedure : comparison with collateral vein pattern in cases of sinistral portal hypertension.

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Strasberg, Steven M; Bhalla, Sanjeev; Sanchez, Luis A; Linehan, David C

2011-11-01

The risks of developing sinistral portal hypertension as a result of occlusion of the splenic vein close to its termination during a Whipple procedure are unclear. Our purpose was to compare the pattern of venous collateral development after splenic vein ligation in an extended Whipple procedure with the pattern of collateral development in cases of sinistral portal hypertension. Five patients underwent an extended Whipple procedure in which the splenic vein was divided and not reconstructed. Six to eight months later detailed mapping of venous return from the spleen was determined by contrast-enhanced multidetector computed tomography or in one case by 3D contrast-enhanced MRI. Spleen size and length of residual patent splenic vein were also measured. The literature on sinistral portal hypertension was evaluated to ascertain whether the venous collateral pattern in cases of left-sided portal hypertension was similar to the pattern that developed when the splenic vein was ligated at its termination in the Whipple procedure. A length of splenic vein remained patent in all five patients, measuring 4.5 to 11.5 cm from the spleen. Splenomegaly did not develop. Blood returned from the spleen by multiple collaterals including collaterals in the omentum and mesocolon. These types of collaterals do not develop in sinistral portal hypertension, nor is residual patent splenic vein seen. Ligation of the splenic vein close to its termination in five patients resulted in a pattern of venous return different from patients that have developed left-sided portal hypertension.

Sodium-hydrogen exchange in erythrocytes of patients with acute deep venous thromboses.

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Polykarpov, S A; Orlov, S N

1992-05-15

The rate of delta microH(+)-induced Na/H-exchange in erythrocytes of patients with occlusive and with floating types of acute deep venous thromboses, and in control volunteers, was estimated. In patients with occlusive thrombi Na/H-exchange was revealed to be fourfold higher in comparison with patients with floating thrombi and with controls, while no difference was observed between the two latter groups.

Celiac artery stenosis/occlusion treated by interventional radiology

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Ikeda, Osamu; Tamura, Yoshitaka; Nakasone, Yutaka; Yamashita, Yasuyuki

2009-01-01

Severe stenosis/occlusion of the proximal celiac trunk due to median arcuate ligament compression (MALC), arteriosclerosis, pancreatitis, tumor invasion, and celiac axis agenesis has been reported. However, clinically significant ischemic bowel disease attributable to celiac axis stenosis/occlusion appears to be rare because the superior mesenteric artery (SMA) provides for rich collateral circulation. In patients with celiac axis stenosis/occlusion, the most important and frequently encountered collateral vessels from the SMA are the pancreaticoduodenal arcades. Patients with celiac artery stenosis/occlusion are treated by interventional radiology (IR) via dilation of the pancreaticoduodenal arcade. In patients with dilation of the pancreaticoduodenal arcade on SMA angiograms, IR through this artery may be successful. Here we provide several tips on surmounting these difficulties in IR including transcatheter arterial chemoembolization for hepatocellular carcinoma, an implantable port system for hepatic arterial infusion chemotherapy to treat metastatic liver tumors, coil embolization of pancreaticoduodenal artery aneurysms, and arterial stimulation test with venous sampling for insulinomas.

Celiac artery stenosis/occlusion treated by interventional radiology

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Ikeda, Osamu [Department of Diagnostic Radiology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences, 1-1-1, Honjo Kumamoto 860-8505 (Japan)], E-mail: osamu-3643ik@do9.enjoy.ne.jp; Tamura, Yoshitaka; Nakasone, Yutaka; Yamashita, Yasuyuki [Department of Diagnostic Radiology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences, 1-1-1, Honjo Kumamoto 860-8505 (Japan)

2009-08-15

Severe stenosis/occlusion of the proximal celiac trunk due to median arcuate ligament compression (MALC), arteriosclerosis, pancreatitis, tumor invasion, and celiac axis agenesis has been reported. However, clinically significant ischemic bowel disease attributable to celiac axis stenosis/occlusion appears to be rare because the superior mesenteric artery (SMA) provides for rich collateral circulation. In patients with celiac axis stenosis/occlusion, the most important and frequently encountered collateral vessels from the SMA are the pancreaticoduodenal arcades. Patients with celiac artery stenosis/occlusion are treated by interventional radiology (IR) via dilation of the pancreaticoduodenal arcade. In patients with dilation of the pancreaticoduodenal arcade on SMA angiograms, IR through this artery may be successful. Here we provide several tips on surmounting these difficulties in IR including transcatheter arterial chemoembolization for hepatocellular carcinoma, an implantable port system for hepatic arterial infusion chemotherapy to treat metastatic liver tumors, coil embolization of pancreaticoduodenal artery aneurysms, and arterial stimulation test with venous sampling for insulinomas.

Pulmonary veno-occlusive disease Report of case and revision of the literature

International Nuclear Information System (INIS)

Jimenez Q, Andres; Palacios, Diana; Camacho D, Fidel

2008-01-01

The real incidence of veno-occlusive pulmonary disease (VOPD) is unknown because it is largely under diagnosed or is not classified as primary pulmonary hypertension, being in fact a variant of the primary disease, primarily affecting post-capillary pulmonary vasculature. It is also known as isolated pulmonary venous sclerosis, obstructive disease of the pulmonary veins or primary pulmonary hypertension of the venous type. VOPD is the result of multiple aggressors associated to a great variety of risk factors. The diagnosis of the disease requires clinical, radiological and pathological features. Vasodilators, immunosuppressants, anticoagulation and oxygen have been proposed as treatments with a poor prognosis, and with reported survival limited by the scarce reporting of cases. We report a case of veno-occlusive pulmonary disease which was diagnosed in this institution.

Hypoplastic left heart syndrome and pulmonary veno-occlusive disease in an infant.

Science.gov (United States)

D'Souza, Marise; Vergales, Jeffrey; Jayakumar, K Anitha

2013-01-01

This report describes an infant with heterotaxy syndrome and severe hypoplasia of the left heart who presented with profound cyanosis at birth despite a large patent ductus arteriosus. Pulmonary venous return was difficult to demonstrate by echocardiography. Angiography showed total anomalous pulmonary venous return via a plexus that drained through the paravertebral veins and bilateral superior vena cavae. Autopsy confirmed these findings, and histopathology demonstrated severe occlusive changes within the pulmonary veins.

Central venous obstruction in hemodialysis patients: the usefulness of percutaneous treatment

International Nuclear Information System (INIS)

Kim, Cheol Young; Goo, Dong Erk; Kim, Dae Ho; Hong, Hyun Suk; Lee, Hae Kyoung; Choi, Duk Lin; Yang, Sung Boo; Moon, Chul

2002-01-01

To analyse the effectiveness of percutaneous treatment of central venous obstruction in patients undergoing hemodialysis. In 100 patients, 107 central venous strictures (56 subclavian (occlusion:21, stenosis:35) and 51 innominate (occlusion:23,stenosis:28)) were assessed, and 170 percutaneous angioplasty procedures were performed. Balloon dilation of the venous lumen was the preferred mode, but if dilation was incomplete we inserted a stent at the site of the stricture. Technical success, procedural complications and the long-term patency rate were evaluated, and the patency difference according to location and degree of stricture, the existence of DM, and any history of central catheter insertion was also determined. We inserted 52 stents in 170 procedures, in 157 (92.4%) of which initial technical success was achieved. Stent migration occurred in two cases and balloon rupture in three. The 6- and 12-month primary patency rates were 46.2% and 24.1%, respectively, and the mean patency rate was 8.5 months. The 1-, 2-and 3-year accumulative patency rates were 59.8%, 47.5% and 35.7%, respectively, and the mean patency rate was 23.5 months. Other than in the history of central catheter insertion, there were no statistically significant differences in patency rates (p=0.0128). In hemodialysis patients with a central venous stricture, percutaneous angioplasty is a safe and useful procedure, but to maintain long-term central venous patency, repeated interventions are required

Significance of venous anastomosis in fingertip replantation.

Science.gov (United States)

Hattori, Yasunori; Doi, Kazuteru; Ikeda, Keisuke; Abe, Yukio; Dhawan, Vikas

2003-03-01

Adequate venous outflow is the most important factor for successful fingertip replantation. The authors have attempted venous anastomosis in all cases of fingertip replantation to overcome postoperative congestion. In this article, the significance of venous repair for fingertip replantation is described from the authors' results of 64 complete fingertip amputations in 55 consecutive patients, which were replanted from January of 1996 to June of 2001. The overall survival rate was 86 percent. Of the 44 replantations in zone I, 37 survived, and the success rate was 84 percent. Of the 20 replantations in zone II, 18 survived, and the success rate was 90 percent. Venous anastomosis was attempted in all cases, but it was possible in 39 zone I and in all zone II replantations. For arterial repair, vein grafts were necessary in 17 of the 44 zone I and in one of the 20 zone II replantations; for venous repair, they were necessary in six zone I replantations and one zone II replantation. Postoperative vascular complications occurred in 15 replantations. There were five cases of arterial thrombosis and 10 cases of venous congestion. Venous congestion occurred in nine zone I and one zone II replantations. In five of these 10 replantations, venous anastomosis was not possible. In another five replantations, venous outflow was established at the time of surgery, but occlusion occurred subsequently. Except for the five failures resulting from arterial thrombosis, successful venous repair was possible in 49 of 59 replantations (83 percent). Despite the demand for skillful microsurgical technique and longer operation time, the authors' results using venous anastomosis in successful fingertip replantations are encouraging. By performing venous anastomosis, external bleeding can be avoided and a higher survival rate can be achieved. Venous anastomosis for fingertip replantation is a reliable and worthwhile procedure.

Life-threatening Cerebral Edema Caused by Acute Occlusion of a Superior Vena Cava Stent

International Nuclear Information System (INIS)

Sofue, Keitaro; Takeuchi, Yoshito; Arai, Yasuaki; Sugimura, Kazuro

2013-01-01

A71-year-old man with advanced lung cancer developed a life-threatening cerebral edema caused by the acute occlusion of a superior vena cava (SVC) stent and was successfully treated by an additional stent placement. Although stent occlusion is a common early complication, no life-threatening situations have been reported until now. Our experience highlights the fact that acute stent occlusion can potentially lead to the complete venous shutdown of the SVC, resulting in life-threatening cerebral edema, after SVC stent placement. Immediate diagnosis and countermeasures are required.

[Digital blood flow measurement by venous occlusion plethysmography in Raynaud's phenomenon. Value of the rewarming test].

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Cristol, R; Debray, J

1986-01-01

The fingertip blood flow measured by mercury strain gauge plethysmography with venous occlusion, at 22 degrees C room temperature, had significantly lower mean values in 190 patients with Raynaud's phenomenon (55 men aged 49 yrs +/- 16, 135 women aged 48 yrs +/- 16) than in 40 age and sex matched controls: 18 ml/100 ml/minute +/- 14.6 versus 35 ml/100 ml/minute +/- 15 at level p less than 0.01. The mean fingertip blood flow was significantly lower (p less than 0.01) in 31 cases of scleroderma and 32 cases of pulpar necrosis (respectively 13 ml +/- 13 and 11 ml +/- 8) than in 55 cases of primary Raynaud's disease (no detectable etiology and normal capillaroscopy 5 years after onset) or in 34 cases of mild Raynaud's phenomenon (respectively 21.6 +/- 16 and 24.4 +/- 18). A warming test (both hands in water at 45 degrees C during 3 minutes) was performed in 50 cases with low basal fingertip blood flow. It induced a "normalized" flow in 22 cases (mostly primary or mild Raynaud), a partly improved flow in 20 cases (mostly secondary Raynaud) and no improvement in 8 cases (scleroderma). The warming test appears to be clinically useful to assess the vasospasm and the vasodilating capabilities.

Blood flow vs. venous pressure effects on filtration coefficient in oleic acid-injured lung.

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Anglade, D; Corboz, M; Menaouar, A; Parker, J C; Sanou, S; Bayat, S; Benchetrit, G; Grimbert, F A

1998-03-01

On the basis of changes in capillary filtration coefficient (Kfc) in 24 rabbit lungs, we determined whether elevations in pulmonary venous pressure (Ppv) or blood flow (BF) produced differences in filtration surface area in oleic acid-injured (OA) or control (Con) lungs. Lungs were cyclically ventilated and perfused under zone 3 conditions by using blood and 5% albumin with no pharmacological modulation of vascular tone. Pulmonary arterial, venous, and capillary pressures were measured by using arterial, venous, and double occlusion. Before and during each Kfc-measurement maneuver, microvascular/total vascular compliance was measured by using venous occlusion. Kfc was measured before and 30 min after injury, by using a Ppv elevation of 7 cmH2O or a BF elevation from 1 to 2 l . min-1 . 100 g-1 to obtain a similar double occlusion pressure. Pulmonary arterial pressure increased more with BF than with Ppv in both Con and OA lungs [29 +/- 2 vs. 19 +/- 0.7 (means +/- SE) cmH2O; P Kfc (200 +/- 40 vs. 83 +/- 14%, respectively; P < 0.01) and microvascular/total vascular compliance ratio (86 +/- 4 vs. 68 +/- 5%, respectively; P < 0.01) increased more with BF than with Ppv. In conclusion, for a given OA-induced increase in hydraulic conductivity, BF elevation increased filtration surface area more than did Ppv elevation. The steep pulmonary pressure profile induced by increased BF could result in the recruitment of injured capillaries and could also shift downstream the compression point of blind (zone 1) and open injured vessels (zone 2).

Central venous catheters: detection of catheter complications and therapeutical options

International Nuclear Information System (INIS)

Gebauer, B.; Beck, A.; Wagner, H.J.; Vivantes-Kliniken, Hellersdorf und Prenzlauer Berg

2008-01-01

For modern medicine central venous catheters play an important role for diagnostic and therapeutic options. Catheter implantation, complication detection and therapy of catheter complications are an increasing demand for the radiologist. The review article provides an overview of different catheter types, their indications, advantages and disadvantages. Catheter malpositions are usually detectable in conventional X-ray. Most malpositions are correctable using interventional-radiological techniques. In addition therapeutical options for thrombotic complications (venous thrombosis, catheter occlusion, fibrin sheath) are discussed. In case of an infectious catheter complication, usually a catheter extraction and re-implantation is necessary

Multicenter study in monitoring central venous catheters complications in hematologic patiennts

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Carmen García Gabás

2013-05-01

Full Text Available Most hematological patients suffer a significant venous damage related to different administrated intravenous therapy, being necessary to place central venous catheters (CVC. CVC is associated with various complications. The most common catheter-related complications are occlusion and infection. To avoid such of them, the development of protocols for insertion and care are needed, as well as recording and following up complications. To this end, we propose a cross-sectional carried out during 13 months whose main goal is to know the incidence of CVC- related complications (mainly occlusion and infection in hematological patients.Population included all the =14 ages patients admitted to different hematological units at Ramon y Cajal and Gregorio Marañón hospitals in Madrid and who signed informed consent. Socio-demographic, clinical characteristics and complications were entered into a log which included a pursuit of care protocol.

Venous intravasation: a potential pitfall of confirmatory hysterosalpingogram following essure hysteroscopic sterilization.

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Chang, Michael C; Shim, John J

2012-09-01

Indications for hysterosalpingography (HSG) include evaluation of infertility, spontaneous abortions, postoperative evaluation of tubal ligation, pre-myomectomy evaluation, and more recently, evaluation of tubal occlusion after placement of the Essure Permanent Birth Control System. Here we report a case of venous intravasation during a routine post-Essure HSG, a phenomenon in which contrast transits from the uterine cavity, through the myometrium, and directly into draining pelvic veins. Venous intravasation is a potential pitfall in interpretation of HSGs.

Central Venous Disease in Hemodialysis Patients: An Update

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Modabber, Milad, E-mail: mmodabber@gmail.com [McMaster University, Michael G. DeGroote School of Medicine (Canada); Kundu, Sanjoy [Scarborough Hospital and Scarborough Vascular Ultrasound, The Vein Institute of Toronto (Canada)

2013-08-01

Central venous occlusive disease (CVD) is a common concern among the hemodialysis patient population, with the potential to cause significant morbidity. Endovascular management of CVD, comprising percutaneous balloon angioplasty and bare-metal stenting, has been established as a safe alternative to open surgical treatment. However, these available treatments have poor long-term patency, requiring close surveillance and multiple repeat interventions. Recently, covered stents have been proposed and their efficacy assessed for the treatment of recalcitrant central venous stenosis and obstruction. Moreover, newly proposed algorithms for the surgical management of CVD warrant consideration. Here, we seek to provide an updated review of the current literature on the various treatment modalities for CVD.

Central venous recanalization in patients with short gut syndrome: restoration of candidacy for intestinal and multivisceral transplantation.

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Lang, Elvira V; Reyes, Jorge; Faintuch, Salomao; Smith, Amy; Abu-Elmagd, Kareem

2005-09-01

To assess feasibility and success of venous recanalization in patients with short gut syndrome who have lost their traditional central venous access and required intestinal or multivisceral transplantation. Twelve patients between the ages of 7 and 55 years with short gut syndrome and long-standing total parenteral nutrition (TPN) dependency and/or hypercoagulability were treated. All had extensive chronic central venous occlusions and survival was dependent on restoration of access and planned transplantation. Central venous recanalizations were obtained via sharp needle recanalization techniques, venous reconstructions with stents, and/or extraanatomic access to the central venous system for placement of central venous tunneled catheters. Central venous access was restored in all patients without operative-related mortality. Three major hemodynamic perioperative technical complications were recorded and successfully treated. There were three self-limited early infectious complications. With a mean follow-up of 22 months, eight of the 12 patients were alive with successful small bowel or multivisceral transplantation; six of those became independent of TPN. The remaining four patients died of complications related to TPN (n = 3) or transplantation (n = 1). With a mean follow-up of 20 months, all but two of the recanalized venous accesses were maintained, for a success rate of 83%. Recanalizations of extensive chronic vein occlusions are feasible but associated with high risk. The technique is life-saving for TPN-dependent patients and can restore candidacy for intestinal and multivisceral transplantation. This approach is likely to be increasingly requested because of the current clinical availability of the transplant procedure.

Effect of PEEP, blood volume, and inspiratory hold maneuvers on venous return.

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Berger, David; Moller, Per W; Weber, Alberto; Bloch, Andreas; Bloechlinger, Stefan; Haenggi, Matthias; Sondergaard, Soren; Jakob, Stephan M; Magder, Sheldon; Takala, Jukka

2016-09-01

According to Guyton's model of circulation, mean systemic filling pressure (MSFP), right atrial pressure (RAP), and resistance to venous return (RVR) determine venous return. MSFP has been estimated from inspiratory hold-induced changes in RAP and blood flow. We studied the effect of positive end-expiratory pressure (PEEP) and blood volume on venous return and MSFP in pigs. MSFP was measured by balloon occlusion of the right atrium (MSFPRAO), and the MSFP obtained via extrapolation of pressure-flow relationships with airway occlusion (MSFPinsp_hold) was extrapolated from RAP/pulmonary artery flow (QPA) relationships during inspiratory holds at PEEP 5 and 10 cmH2O, after bleeding, and in hypervolemia. MSFPRAO increased with PEEP [PEEP 5, 12.9 (SD 2.5) mmHg; PEEP 10, 14.0 (SD 2.6) mmHg, P = 0.002] without change in QPA [2.75 (SD 0.43) vs. 2.56 (SD 0.45) l/min, P = 0.094]. MSFPRAO decreased after bleeding and increased in hypervolemia [10.8 (SD 2.2) and 16.4 (SD 3.0) mmHg, respectively, P waterfall. Copyright © 2016 the American Physiological Society.

Progression of Diabetic Capillary Occlusion: A Model.

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Xiao Fu

2016-06-01

Full Text Available An explanatory computational model is developed of the contiguous areas of retinal capillary loss which play a large role in diabetic maculapathy and diabetic retinal neovascularization. Strictly random leukocyte mediated capillary occlusion cannot explain the occurrence of large contiguous areas of retinal ischemia. Therefore occlusion of an individual capillary must increase the probability of occlusion of surrounding capillaries. A retinal perifoveal vascular sector as well as a peripheral retinal capillary network and a deleted hexagonal capillary network are modelled using Compucell3D. The perifoveal modelling produces a pattern of spreading capillary loss with associated macular edema. In the peripheral network, spreading ischemia results from the progressive loss of the ladder capillaries which connect peripheral arterioles and venules. System blood flow was elevated in the macular model before a later reduction in flow in cases with progression of capillary occlusions. Simulations differing only in initial vascular network structures but with identical dynamics for oxygen, growth factors and vascular occlusions, replicate key clinical observations of ischemia and macular edema in the posterior pole and ischemia in the retinal periphery. The simulation results also seem consistent with quantitative data on macular blood flow and qualitative data on venous oxygenation. One computational model applied to distinct capillary networks in different retinal regions yielded results comparable to clinical observations in those regions.

Micro Vascular Plug (MVP)-assisted vessel occlusion in neurovascular pathologies: technical results and initial clinical experience.

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Beaty, Narlin B; Jindal, Gaurav; Gandhi, Dheeraj

2015-10-01

Deconstructive approaches may be necessary to treat a variety of neurovascular pathologies. Recently, a new device has become available for endovascular arterial occlusion that may have unique applications in neurovascular disease. The Micro Vascular Plug (MVP, Reverse Medical, Irvine, California, USA) has been designed for vessel occlusion through targeted embolization. To report the results from our initial experience with eight consecutive patients in whom the MVP was used to achieve endovascular occlusion of an artery in the head and neck. Eight consecutive patients treated over a nine-month period were included. The patients' radiographic and electronic medical records were retrospectively reviewed. Specifically demographic information, clinical indication, site of arterial occlusion, size of MVP, time to vessel occlusion, clinical complications, use of other secondary embolic agents, and clinical outcome were recorded. Follow-up information when available is presented. The MVP was used in eight patients for the treatment of neurovascular disease. Indications for treatment included post-traumatic head/neck bleeding (n=3), carotid-cavernous fistula (1), vertebral-vertebral fistula (1), giant fusiform vertebral aneurysm (1), stump-emboli after carotid dissection (1), and iatrogenic vertebral artery penetrating injury (1). One device was used in five patients, two in two patients, and one patient with extensive vertebral-vertebral venous fistula required three plugs to effectively trap the fistula from proximal and distal aspects. Vessel occlusion was obtained in MVP in neurovascular disease. Use of this device may be associated with shorter procedural times and cost savings in comparison with the use of microcoils for vessel occlusion. Our experience shows that MVP can have unique applications in neurovascular pathologies and it complements other occlusive devices. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted

THE AZYGOS VENOUS SYSTEM AND ITS ANATOMICAL VARIATIONS

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Madiki Sudhakara Rao

2016-06-01

Full Text Available AIMS AND OBJECTIVES Azygos veins are important cavocaval and portacaval junctions, which form a collateral circulation in caval vein occlusion and in portal hypertension, cirrhosis of liver. The unpaired azygos venous system consists of azygos vein, hemiazygos vein and accessory azygos vein. This system of veins, along with its mediastinal, bronchial and oesophageal tributaries drains most of the body wall of trunk, namely posterior abdominal and thoracic wall. Anatomical variations of this unpaired azygos venous system are clinically important. AIMS To study and report the occurrence of anatomical variations of the unpaired azygos venous system in the region of East Godavari District, Andhra Pradesh (India. METHODS The present study was carried out in the Department of Anatomy, KIMS & RF, Amalapuram and G.S.L. Medical College, Rajahmundry over a period of 2 years. The present study was conducted on 60 cadavers (irrespective of age and sex. The entire course of the azygos venous system in these 60 cadavers was carefully observed and documented. RESULTS Anatomical variations were present in 16.66% of cases, out of which three distinct types were identified. 6.6% exhibited two separate azygos venous systems with no communications, 5% with communication between the left brachiocephalic vein and the azygos vein and 5% presence of post-aortic venous channels. CONCLUSION Variations of azygos venous system may be wrongly dubbed as aneurysm, lymphadenopathy or other abnormalities while reporting a CT scan of mediastinum. Venous anomalies are also detected only during surgery. The most troublesome intraoperative hazard is haemorrhage, which is mainly of venous origin. To avoid such situations is to have an awareness and knowledge of the expected venous anomalies.

Effect of hepatic venous sphincter contraction on transmission of central venous pressure to lobar and portal pressure.

Science.gov (United States)

Lautt, W W; Legare, D J; Greenway, C V

1987-11-01

In dogs anesthetized with pentobarbital, central vena caval pressure (CVP), portal venous pressure (PVP), and intrahepatic lobar venous pressure (proximal to the hepatic venous sphincters) were measured. The objective was to determine some characteristics of the intrahepatic vascular resistance sites (proximal and distal to the hepatic venous sphincters) including testing predictions made using a recent mathematical model of distensible hepatic venous resistance. The stimulus used was a brief rise in CVP produced by transient occlusion of the thoracic vena cava in control state and when vascular resistance was elevated by infusions of norepinephrine or histamine, or by nerve stimulation. The percent transmission of the downstream pressure rise to upstream sites past areas of vascular resistance was elevated. Even small increments in CVP are partially transmitted upstream. The data are incompatible with the vascular waterfall phenomenon which predicts that venous pressure increments are not transmitted upstream until a critical pressure is overcome and then further increments would be 100% transmitted. The hepatic sphincters show the following characteristics. First, small rises in CVP are transmitted less than large elevations; as the CVP rises, the sphincters passively distend and allow a greater percent transmission upstream, thus a large rise in CVP is more fully transmitted than a small rise in CVP. Second, the amount of pressure transmission upstream is determined by the vascular resistance across which the pressure is transmitted. As nerves, norepinephrine, or histamine cause the hepatic sphincters to contract, the percent transmission becomes less and the distensibility of the sphincters is reduced. Similar characteristics are shown for the "presinusoidal" vascular resistance and the hepatic venous sphincter resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

CT-Guided Superior Vena Cava Puncture: A Solution to Re-Establishing Access in Haemodialysis-Related Central Venous Occlusion Refractory to Conventional Endovascular Techniques

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Khalifa, Mohamed, E-mail: mkhalifa@nhs.net; Patel, Neeral R., E-mail: neeral.patel06@gmail.com; Moser, Steven, E-mail: steven.moser@imperial.nhs.uk [Hammersmith Hospital, Department of Radiology, Imperial College Healthcare NHS Trust (United Kingdom)

2016-04-15

PurposeThe purpose of this technical note is to demonstrate the novel use of CT-guided superior vena cava (SVC) puncture and subsequent tunnelled haemodialysis (HD) line placement in end-stage renal failure (ESRF) patients with central venous obstruction refractory to conventional percutaneous venoplasty (PTV) and wire transgression, thereby allowing resumption of HD.MethodsThree successive ESRF patients underwent CT-guided SVC puncture with subsequent tract recanalisation. Ultrasound-guided puncture of the right internal jugular vein was performed, the needle advanced to the patent SVC under CT guidance, with subsequent insertion of a stabilisation guidewire. Following appropriate tract angioplasty, twin-tunnelled HD catheters were inserted and HD resumed.ResultsNo immediate complications were identified. There was resumption of HD in all three patients with a 100 % success rate. One patient’s HD catheter remained in use for 2 years post-procedure, and another remains functional 1 year to the present day. One patient died 2 weeks after the procedure due to pancreatitis-related abdominal sepsis unrelated to the Tesio lines.ConclusionCT-guided SVC puncture and tunnelled HD line insertion in HD-related central venous occlusion (CVO) refractory to conventional recanalisation options can be performed safely, requires no extra equipment and lies within the skill set and resources of most interventional radiology departments involved in the management of HD patients.

Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

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Arabi, Mohammad, E-mail: marabi2004@hotmail.com; Ahmed, Ishtiaq; Mat’hami, Abdulaziz [Prince Sultan Military Medical City (PSMMC), Division of Endovascular Interventional Radiology, Department of Medical Imaging (Saudi Arabia); Ahmed, Dildar; Aslam, Naveed [Prince Sultan Military Medical City (PSMMC), Department of Nephrology (Saudi Arabia)

2016-06-15

PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

International Nuclear Information System (INIS)

Arabi, Mohammad; Ahmed, Ishtiaq; Mat’hami, Abdulaziz; Ahmed, Dildar; Aslam, Naveed

2016-01-01

PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

Development of a middle cerebral artery occlusion model in the nonhuman primate and a safety study of i.v. infusion of human mesenchymal stem cells.

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Masanori Sasaki

Full Text Available Most experimental stroke research is carried out in rodents, but given differences between rodents and human, nonhuman primate (NHP models may provide a valuable tool to study therapeutic interventions. The authors developed a surgical method for transient occlusion of the M1 branch of middle cerebral artery (MCA in the African green monkey to evaluate safety aspects of intravenous infusion of mesenchymal stem cells (hMSCs derived from human bone marrow.The left Sylvian fissure was exposed by a small fronto-temporal craniotomy. The M1 branch of the MCA was exposed by microsurgical dissection and clipped for 2 to 4 hours. Neurological examinations and magnetic resonance imaging (MRI were carried out at regular post-operative course. hMSCs were infused 1 hour after reperfusion (clip release in the 3-hour occlusion model.During M1 occlusion, two patterns of changes were observed in the lateral hemisphere surface. One pattern (Pattern 1 was darkening of venous blood, small vessel collapse, and blood pooling with no venous return in cortical veins. Animals with these three features had severe and lasting hemiplegia and MRI demonstrated extensive MCA territory infarction. Animals in the second pattern (Pattern 2 displayed darkening of venous blood, small vessel collapse, and reduced but incompletely occluded venous flow and the functional deficit was much less severe and MRI indicated smaller infarction areas in brain. The severe group (Pattern 1 likely had less extensive collateral circulation than the less severe group (Pattern 2 where venous pooling of blood was not observed. The hMSC infused animals showed a trend for greater functional improvement that was not statistically significant in the acute phase and no additive negative effects.These results indicate inter-animal variability of collateral circulation after complete M1 occlusion and that hMSC infusion is safe in the developed NHP stroke model.

Central retinal vein occlusion with cilioretinal infarction from branch flow exclusion and choroidal arterial steal.

Science.gov (United States)

McLeod, David

2009-01-01

The first definitive study of retinal vein occlusion complicated by infarction within the territory of one or more cilioretinal arteries was published in 1976. Many individual cases and further case series have been reported in the interim, but the nature of the interrelationship is still under debate. A review was undertaken of the relevant clinical and fundus fluorescein angiographic characteristics of this combined retinal vascular disorder together with the pathophysiological mechanisms currently presented in the literature to explain their association. Scientific publications up to 2008 were evaluated by one of the authors of the original report. There are broad similarities between publications in their descriptions of the clinical features, but significant differences of detail and interpretation are also evident. Most of the mechanisms so far proposed to account for cilioretinal infarction after central or hemisphere retinal vein occlusion do not withstand critical scrutiny. Two related hypotheses are expounded that appear to satisfactorily elucidate this interrelationship -- branch flow exclusion and branch flow diversion (otherwise termed "choroidal arterial steal"). In eyes with a cilioretinal supply, the probability that cilioretinal infarction will complicate retinal vein occlusion increases with increasing severity of venous obstruction and the more distally the cilioretinal artery arises from the posterior ciliary arterial tree. A distal branch point also facilitates observation of dye front reciprocation within the artery. Indicators of the degree of venous obstruction that may be necessary to instigate cilioretinal infarction include very prolonged dye transit times in the central retinal circulation, exaggerated venous cyanosis and tortuosity, perivenous cotton-wool sentinels, and macular perivenular whitening.

Antiphospholipid Syndrome and Vascular Ischemic (Occlusive) Diseases: An Overview

Science.gov (United States)

2007-01-01

Antiphospholipid syndrome (APS) is primarily considered to be an autoimmune pathological condition that is also referred to as "Hughes syndrome". It is characterized by arterial and/or venous thrombosis and pregnancy pathologies in the presence of anticardiolipin antibodies and/or lupus anticoagulant. APS can occur either as a primary disease or secondary to a connective tissue disorder, most frequently systemic lupus erythematosus (SLE). Damage to the nervous system is one of the most prominent clinical constellations of sequelae in APS and includes (i) arterial/venous thrombotic events, (ii) psychiatric features and (iii) other non-thrombotic neurological syndromes. In this overview we compare the most important vascular ischemic (occlusive) disturbances (VIOD) with neuro-psychiatric symptomatics, together with complete, updated classifications and hypotheses for the etio-pathogenesis of APS with underlying clinical and laboratory criteria for optimal diagnosis and disease management. PMID:18159581

Association between duration of coronary occlusion and high-intensity signal on T1-weighted magnetic resonance imaging among patients with angiographic total occlusion

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Matsumoto, Kenji; Ehara, Shoichi; Hasegawa, Takao; Sakaguchi, Mikumo; Shimada, Kenei [Osaka City University Graduate School of Medicine, Department of Cardiovascular Medicine, Abeno-ku, Osaka (Japan)

2017-09-15

To evaluate the association between duration of the coronary occlusion and high-intensity signal (HIS) on noncontrast T1-weighted imaging using a 1.5-T magnetic resonance imager among patients with angiographic coronary total occlusion. The signal intensity of the coronary target area divided by the signal intensity of the left ventricular muscle near the target area at each site (TMR) was measured. Areas with a TMR >1.0 were defined as HIS. Thirty five lesions from 33 patients were divided into the following three groups: subacute occlusion (up to 3 months; n = 7), short-duration chronic total occlusion (SD-CTO: 3-6 months; n = 9) and long-duration CTO (LD-CTO: ≥6 months; n = 19). All subacute occlusion lesions showed a HIS within the occlusion site. Among patients with CTO, the frequency of a HIS within the occlusion site was significantly higher in SD-CTO than in LD-CTO lesions (p = 0.013). In multivariate analyses, only an occlusion duration of less than 6 months was an independent factor associated with the presence of HIS (odds ratio 7.6, 95% CI 1.1-54.5; p = 0.044). The presence of a HIS in the occlusion site was associated more with SD-CTO than with LD-CTO among patients with CTO. (orig.)

Association between duration of coronary occlusion and high-intensity signal on T1-weighted magnetic resonance imaging among patients with angiographic total occlusion

International Nuclear Information System (INIS)

Matsumoto, Kenji; Ehara, Shoichi; Hasegawa, Takao; Sakaguchi, Mikumo; Shimada, Kenei

2017-01-01

To evaluate the association between duration of the coronary occlusion and high-intensity signal (HIS) on noncontrast T1-weighted imaging using a 1.5-T magnetic resonance imager among patients with angiographic coronary total occlusion. The signal intensity of the coronary target area divided by the signal intensity of the left ventricular muscle near the target area at each site (TMR) was measured. Areas with a TMR >1.0 were defined as HIS. Thirty five lesions from 33 patients were divided into the following three groups: subacute occlusion (up to 3 months; n = 7), short-duration chronic total occlusion (SD-CTO: 3-6 months; n = 9) and long-duration CTO (LD-CTO: ≥6 months; n = 19). All subacute occlusion lesions showed a HIS within the occlusion site. Among patients with CTO, the frequency of a HIS within the occlusion site was significantly higher in SD-CTO than in LD-CTO lesions (p = 0.013). In multivariate analyses, only an occlusion duration of less than 6 months was an independent factor associated with the presence of HIS (odds ratio 7.6, 95% CI 1.1-54.5; p = 0.044). The presence of a HIS in the occlusion site was associated more with SD-CTO than with LD-CTO among patients with CTO. (orig.)

The effect of peripherally inserted central catheter (PICC) valve technology on catheter occlusion rates--the 'ELeCTRiC' study.

Science.gov (United States)

Johnston, Andrew J; Streater, Carmel T; Noorani, Remy; Crofts, Joanne L; Del Mundo, Aldwin B; Parker, Richard A

2012-01-01

Peripherally Inserted Central Catheters (PICCs) are increasingly being used to provide short to medium-term central venous access. The current study was designed to test the hypothesis that PICC valve technology does not influence PICC occlusion rates. Intensive care unit (ICU) patients who required a PICC were randomized to one of three types of dual lumen PICC (open ended non-valved, Groshong valve, PASV valve). PICC occlusions were recorded and managed with a protocol that used urokinase. A total of 102 patients were recruited to the study. The overall risk of occlusion per catheter was 35% (95% CI 26% to 44%). The overall rate of occlusion was 76 occlusions per 1000 catheter days (95% CI 61 to 95). Presence or type of valve did not significantly influence this rate (open-ended non-valved PICC 38% of catheters, 79 occlusions per 1000 catheter days; Groshong 38% of catheters, 60 occlusions per 1000 catheter days; PASV 27% of catheters, 99 occlusions per 1000 catheter days). The dose of urokinase required to treat PICC occlusions did not significantly differ between PICC types. Valved PICCs do not appear to influence PICC occlusion rates.

Venous Intravasation: A Potential Pitfall of Confirmatory Hysterosalpingogram Following Essure Hysteroscopic Sterilization

OpenAIRE

Chang, Michael C.; Shim, John J.

2012-01-01

Indications for hysterosalpingography (HSG) include evaluation of infertility, spontaneous abortions, postoperative evaluation of tubal ligation, pre-myomectomy evaluation, and more recently, evaluation of tubal occlusion after placement of the Essure Permanent Birth Control System. Here we report a case of venous intravasation during a routine post-Essure HSG, a phenomenon in which contrast transits from the uterine cavity, through the myometrium, and directly into draining pelvic veins. Ven...

A pilot study and novel angiographic classification for superior sagittal sinus stenting in patients with non-thrombotic intracranial venous occlusive disease.

Science.gov (United States)

Raper, Daniel M S; Buell, Thomas J; Ding, Dale; Pomeraniec, I Jonathan; Crowley, R Webster; Liu, Kenneth C

2018-01-01

Safety and efficacy of superior sagittal sinus (SSS) stenting for non-thrombotic intracranial venous occlusive disease (VOD) is unknown. The aim of this retrospective cohort study is to evaluate outcomes after SSS stenting. We evaluated an institutional database to identify patients who underwent SSS stenting. Radiographic and clinical outcomes were analyzed and a novel angiographic classification of the SSS was proposed. We identified 19 patients; 42% developed SSS stenosis after transverse sinus stenting. Pre-stent maximum mean venous pressure (MVP) in the SSS of 16.2 mm Hg decreased to 13.1 mm Hg after stenting (p=0.037). Preoperative trans-stenosis pressure gradient of 4.2 mm Hg decreased to 1.5 mm Hg after stenting (pSSS stenosis distal to the stent construct was noted. Improvement in headache, tinnitus, and visual obscurations was reported by 66.7%, 63.6%, and 50% of affected patients, respectively, at mean follow-up of 5.2 months. We divided the SSS into four anatomically equal segments, numbered S1-S4, from the torcula to frontal pole. SSS stenosis typically occurs in the S1 segment, and the anterior extent of SSS stents was deployed at the S1-S2 junction in all but one case. SSS stenting is reasonably safe, may improve clinical symptoms, and significantly reduces maximum MVP and trans-stenosis pressure gradients in patients with VOD with SSS stenosis. The S1 segment is most commonly stenotic, and minimum pressure gradients for symptomatic SSS stenosis may be lower than for transverse or sigmoid stenosis. Additional studies and follow-up are necessary to better elucidate appropriate clinical indications and long-term efficacy of SSS stenting. 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/.

Quantitative estimation of compliance of human systemic veins by occlusion plethysmography with radionuclide

International Nuclear Information System (INIS)

Takatsu, Hisato; Gotoh, Kohshi; Suzuki, Takahiko; Ohsumi, Yukio; Yagi, Yasuo; Tsukamoto, Tatsuo; Terashima, Yasushi; Nagashima, Kenshi; Hirakawa, Senri

1989-01-01

Volume-pressure relationship and compliance of human systemic veins were estimated quantitatively and noninvasively using radionuclide. The effect of nitroglycerin (NTG) on these parameters was examined. Plethysmography with radionuclide (RN) was performed using the occlusion method on the forearm in 56 patients with various cardiac diseases after RN angiocardiography with 99m Tc-RBC. The RN counts-venous pressure curve was constructed from (1) the changes in radioactivity from region of interest on the forearm that were considered to reflect the changes in the blood volume of the forearm, and (2) the changes in the pressure of the forearm vein (fv) due to venous occlusion. The specific compliance of the forearm veins (Csp.fv; (1/V)·(ΔV/ΔP)) was obtained graphically from this curve at each patient's venous pressure (Pv). Csp.fv was 0.044±0.012 mmHg -1 in class I (mean±SD; n=13), 0.033±0.007 mmHg -1 in class II (n=30), and 0.019±0.007 mmHg -1 in class III (n=13), of the previous NYHA classification of work tolerance. There were significant differences in Csp.fv among the three classes. The systemic venous blood volume (Vsv) was determined by subtracting the central blood volume, measured by RN-angiocardiography, from total blood volume, measured by the indicator dilution method utilizing 131 I-human serum albumin. Systemic venous compliance (Csv) was calculated from Csv=Csp.fv·Vsv. The Csv was 127.2±24.8 ml·mmHg -1 (mean±SD) in class I, 101.1±24.1 ml·mmHg -1 in class II and 62.2±28.1 ml·mmHg -1 in class III. There were significant differences in Csv among the three classes. The class I Csv value was calculated to be 127.2±24.8 ml·mmHg -1 and the Csv/body weight was calculated to be 2.3±0.7 ml·mmHg -1 ·kg -1 of body weight. The administration of NTG increased Csv significantly in all cases. (J.P.N.)

Work in progress. Transcatheter thermal venous occlusion: a new technique

International Nuclear Information System (INIS)

Rholl, K.S.; Rysavy, J.A.; Vlodaver, Z.; Cragg, A.H.; Castaneda-Zuniga, W.R.; Amplatz, K.

1982-01-01

Diatrizoate (76%) contrast agent heated to 100 0 C was injected into the veins of dogs and one human volunteer for the nonsurgical occlusion of the vessels. Follow-up venograms and histologic examinations, at intervals varying from one day to four weeks later, revealed thrombosis of the injected veins in all animals. Thrombosis occurred one to five days after injection of contrast agent. The authors conclude that hot contrast medium is a safe and convenient agent for inducing thrombosis. It is much easier to use than mechanical devices, tissue glues, and plastics, which involve complex procedures and specialized equipment. In contrast to other sclerosing agents, hot contrast agent is rapidly converted into a nonsclerosing agent by cooling. The new technique allows a more controlled thremal injury to the vascular wall and is under fluoroscopic control

Lower body positive pressure application with an antigravity suit in acute carotid occlusion.

Science.gov (United States)

Berthet, Karine; Lukaszewicz, Anne Claire; Bousser, Marie-Germaine; Payen, Didier

2010-04-01

The challenge in acute stroke is still to reperfuse as early as possible the ischemic territory. Since fibrinolytic therapies have a limited window with potential risk of bleeding, having a nonpharmacologic mean to recruit vessels in area surrounding necrosis might be useful. We propose here to use antigravity suit inflated at "venous" pressure levels to shift blood towards thoracic and brain territories. We report two cases of spectacular clinical recovery after acute carotid occlusion.

Popliteal Venous Aneurysm: A Rare Cause of Recurrent Pulmonary Emboli and Limb Swelling

International Nuclear Information System (INIS)

Russell, David A.; Robinson, Graham J.; Johnson, Brian F.

2008-01-01

Popliteal venous aneurysm is a rare cause of recurrent pulmonary embolism, although the true incidence of aneurysm is probably underestimated. One-third of patients suffer further embolic events despite therapeutic anticoagulation. We report the case of a 59-year-old male who presented with recurrent PEs over a period of 12 years despite anticoagulation therapy. A thrombophilia screen and abdominal ultrasound were normal at that time. He reattended with recurrent pulmonary emboli, left calf swelling, and a mass in his left popliteal fossa causing limitation of knee movement. Venous duplex and MRI of his popliteal fossa demonstrated a thrombosed true popliteal venous aneurysm with popliteal and superficial femoral vein occlusion. In view of the mass effect we proceeded to surgical excision of his aneurysm after prophylactic placement of an IVC filter. The patient regained normal knee function with intensive inpatient physiotherapy. He has been recommenced on lifelong anticoagulant. The presentation, investigation, and management of the condition are briefly discussed. We suggest that a bilateral lower limb duplex is performed to exclude venous aneurysm in all patients presenting with pulmonary embolism in which an underlying source cannot otherwise be identified and no thrombophilic tendency is detected.

Veno occlusive disease: Update on clinical management

Science.gov (United States)

Senzolo, M; Germani, G; Cholongitas, E; Burra, P; Burroughs, AK

2007-01-01

Hepatic veno-occlusive disease is a clinical syndrome characterized by hepatomegaly, ascites, weight gain and jaundice, due to sinusoidal congestion which can be caused by alkaloid ingestion, but the most frequent cause is haematopoietic stem cell transplantation (STC) and is also seen after solid organ transplantation. The incidence of veno occlusive disease (VOD) after STC ranges from 0 to 70%, but is decreasing. Survival is good when VOD is a mild form, but when it is severe and associated with an increase of hepatic venous pressure gradient > 20 mmHg, and mortality is about 90%. Prevention remains the best therapeutic strategy, by using non-myeloablative conditioning regimens before STC. Prophylactic administration of ursodeoxycholic acid, being an antioxidant and antiapoptotic agent, can have some benefit in reducing overall mortality. Defibrotide, which has pro-fibrinolytic and antithrombotic properties, is the most effective therapy; decompression of the sinusoids by a transjugular intrahepatic portosystemic shunt (TIPS) can be tried, especially to treat VOD after liver transplantation and when multiorgan failure (MOF) is not present. Liver transplantation can be the last option, but can not be considered a standard rescue therapy, because usually the concomitant presence of multiorgan failure contraindicates this procedure. PMID:17663504

The non-target bi-ovarian branches occlusion in fibroids embolization on resumption of menses and ovarian function

International Nuclear Information System (INIS)

Guo Wenbo; Yang Jianyong; Chen Wei; Zhuang Wenquan; Yao Shuzhong

2005-01-01

Objective: To evaluate the effect of the non-target bi-ovarian branches occlusion in fibroids embolization on resumption of menses and ovarian function. Methods: The patients with the non-target bi-ovarian branches occlusion in uterine fibroids embolization (UFE) were classified into two groups, one for lipiodol deposited in bi-ovarian areas (Group A) , another for non lipiodol deposited in ovarian areas or in single ovarian area (Group B of non lipiodol deposited in bi-ovarian areas). The statistical difference between the data of group A and group B were assessed with Fisher test. All UFE were performed with the mixture of lipiodol and pingyangmycin. The serum level of Follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) were measured before UFE and 6 months after UFE. The statistical difference between the data of before and after UFE was assessed with t test. Results: Fifteen patients [age ranged 26-46 years, average (39.00 ± 5.62) years] had been followed up for an average (30.5±6.4) months (range 16-47 months). In 12 of 15, regular menses resumed after an average of (3.0 ±0.3) weeks (range 2-6 weeks). In 3 of 15 (20%), regular menses did not resume. The sexual hormone findings of menopause were found in three cases with amenorrhea after UFE. Amenorrhea was found in three cases with lipiodol deposited in bi-ovarian areas (Group A). Non-amenorrhea was found in the group of non-lipiodol deposited in bi-ovarian areas (Group B). There were significant statistical difference between Group A and Group B (P=0.002 19). Non amenorrhea was found in the patients aged over 45 years old. Three patients were found amenorrhea in the patients aged younger than 45 years old. There were no significant statistical difference between the serum level of FSH, LH and E2 before and 6 months after UFE (P>0.05). Conclusion: The incidence of amenorrhea is very high in the patients with lipiodol deposited in bi-ovarian areas when the bi-ovarian branches of

The modified pulse-spray method using Urokinase in subacute and chronic thrombotic arterial occlusion

International Nuclear Information System (INIS)

Kim, Youn Kil; Hahn, Seong Tae; Baek, Jee Hee; Kim, Choon Yul; Shinn, Kyung Sub

1996-01-01

To evaluate the effectiveness and safety of the modified pulse-spray method using Urokinase(UK) in subacute and chronic thrombotic arterial occlusion. Modified pulse-spray methods using UK were performed in seven patients with subacute (1 week-1month) to chronic (1month-5years) occlusive symptoms such as limb pain, claudication and impotence. Angiographic examination revealed thrombotic occlusion of the aorta, common iliac arteries, brachial arterio-venous hemodialysis graft and femoro-popliteal bypass graft. The patients underwent thrombolysis using modified pulse-spray and additional constant infusion of UK. In the presence of underlying stenosis or organized clots, balloon angioplasty or stent placement was performed. Complete lysis was obtained in five of seven patients. For initial lysis, the mean dose of UK was 420,000 units, and the mean modified pulse-spray time was 50 minutes. Mean total dose of UK and mean total time for complete lysis were 800,000 units and 161 minutes, respectively. Thrombolysis of the femoro-popliteal bypass graft failed due to severe occlusion of the distal anastomosis. Partial lysis was achieved in one patient with aorto-illac occlusion, but further thrombolysis was stopped due to bleeding at the puncture site. The modified pulse-spray method using UK is effective in treating subacute and chronic arterial thrombotic occlusion. It augments the speed, safety and efficacy of thrombolysis. When underlying stenosis or organized clots remain after thrombolysis, ballon angioplasty or stent placement would be helpful

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

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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.

[Complete denture occlusion considered from occlusal contacts during mastication].

Science.gov (United States)

Suzuki, Tetsuya

2004-12-01

Few reports describe the functional superiority of full balanced occlusion to that of lingualized occlusion. Recently, a bilateral balanced scheme has been much more generally applied than a unilateral balanced scheme in lingualized occlusion as well as in full balanced occlusion. Occlusal contacts on the non-chewing side occur earlier than on the chewing side;in the order of second molar, first molar, and then premolars. The contact on the balancing side contributes to the prevention of denture dislocation and guidance from eccentric positions to the centric occlusal position during mastication. Therefore, bilateral balanced occlusion was shown to be effective for denture stability during mastication with complete dentures. Today's typical edentulous patients have greater mean age than in the past, and thus are seen with severe alveolar bone resorption, thin mucosa and sometimes abnormalities of the maxillomandibular relation. Their occlusal positions are often unstable and changeable after insertion of complete dentures. Because lingualized occlusion allows for easier accommodation and correction, lingualized occlusion is more suitable for such cases than full balanced occlusion, which requires a strict occlusal relationship. In light of the standard Japanese diet, there is some doubt about why lingualized occlusion might be suitable for Japanese edentulous patients in terms of the sense of mastication. A method of evaluating the sense of mastication needs to be established.

Catheter-directed thrombolysis of below-knee deep venous thrombosis of the lower extremities

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Roh, Byung Suk; Sohn, Young Jun; Heo, Eun A; Cho, Hyun Sun; Park, Seong Hoon; Lee, Young Hwan [Wonkwang University Hospital, Iksan (Korea, Republic of)

2008-02-15

To evaluate the technical feasibility and clinical efficacy of the use of local thrombolysis for below-knee deep vein thrombosis (DVT). From a population of 41 patients with a lower extremity DVT, the prospective clinical trial included 11 patients (7 female, 4 male, average age 61.4 years) treated with catheter-directed thrombolysis with urokinase for below-knee DVT. After removal of the proximal ilofemoral DVT, additional interventional procedures to remove the residual thrombosis and restore the venous flow from the below-knee vein were performed in cases of continuous occlusion of venous flow from the popliteal and tibial veins. Under ultrasound (US) guidance, catheter-directed thrombolysis with urokinase was performed through the ipsilateral popliteal vein. After administration of oral anticoagulation therapy, CT and venography were performed to identify patency and the presence of a recurrent thrombosis. Successful removal of the thrombus and restoration of venous flow were achieved in all of the patients (100%). Restoration of flow with a residual thrombus occurred in one case. Focal venous stenosis was discovered in four cases. The duration of urokinase infusion was 1-4 days (average 2.36 days), which was considered long. For 15.2 months, the venous lumen of all cases was preserved without a recurrent thrombosis. Catheter-directed thrombolysis is an effective procedure for recanalization of below-knee DVT in patients with a lower extremity DVT.

Catheter-directed thrombolysis of below-knee deep venous thrombosis of the lower extremities

International Nuclear Information System (INIS)

Roh, Byung Suk; Sohn, Young Jun; Heo, Eun A; Cho, Hyun Sun; Park, Seong Hoon; Lee, Young Hwan

2008-01-01

To evaluate the technical feasibility and clinical efficacy of the use of local thrombolysis for below-knee deep vein thrombosis (DVT). From a population of 41 patients with a lower extremity DVT, the prospective clinical trial included 11 patients (7 female, 4 male, average age 61.4 years) treated with catheter-directed thrombolysis with urokinase for below-knee DVT. After removal of the proximal ilofemoral DVT, additional interventional procedures to remove the residual thrombosis and restore the venous flow from the below-knee vein were performed in cases of continuous occlusion of venous flow from the popliteal and tibial veins. Under ultrasound (US) guidance, catheter-directed thrombolysis with urokinase was performed through the ipsilateral popliteal vein. After administration of oral anticoagulation therapy, CT and venography were performed to identify patency and the presence of a recurrent thrombosis. Successful removal of the thrombus and restoration of venous flow were achieved in all of the patients (100%). Restoration of flow with a residual thrombus occurred in one case. Focal venous stenosis was discovered in four cases. The duration of urokinase infusion was 1-4 days (average 2.36 days), which was considered long. For 15.2 months, the venous lumen of all cases was preserved without a recurrent thrombosis. Catheter-directed thrombolysis is an effective procedure for recanalization of below-knee DVT in patients with a lower extremity DVT

Peripheral venous distension elicits a blood pressure raising reflex in young and middle-aged adults.

Science.gov (United States)

Matthews, Evan L; Brian, Michael S; Coyle, Dana E; Edwards, David G; Stocker, Sean D; Wenner, Megan M; Farquhar, William B

2016-06-01

Distension of peripheral veins in humans elicits a pressor and sympathoexcitatory response that is mediated through group III/IV skeletal muscle afferents. There is some evidence that autonomic reflexes mediated by these sensory fibers are blunted with increasing age, yet to date the venous distension reflex has only been studied in young adults. Therefore, we tested the hypothesis that the venous distension reflex would be attenuated in middle-aged compared with young adults. Nineteen young (14 men/5 women, 25 ± 1 yr) and 13 middle-aged (9 men/4 women, 50 ± 2 yr) healthy normotensive participants underwent venous distension via saline infusion through a retrograde intravenous catheter in an antecubital vein during limb occlusion. Beat-by-beat blood pressure, muscle sympathetic nerve activity (MSNA), and model flow-derived cardiac output (Q), and total peripheral resistance (TPR) were recorded throughout the trial. Mean arterial pressure (MAP) increased during the venous distension in both young (baseline 83 ± 2, peak 94 ± 3 mmHg; P blood pressure, MSNA, and TPR were similar between young and middle-aged adults. Additionally, no correlation was found between age and the response to venous distension (all P > 0.05). These findings suggest that peripheral venous distension elicits a pressor and sympathetic response in middle-aged adults similar to the response observed in young adults. Copyright © 2016 the American Physiological Society.

[Relationship between Occlusal Discomfort Syndrome and Occlusal Threshold].

Science.gov (United States)

Munakata, Motohiro; Ono, Yumie; Hayama, Rika; Kataoka, Kanako; Ikuta, Ryuhei; Tamaki, Katsushi

2016-03-01

Occlusal dysesthesia has been defined as persistent uncomfortable feelings of intercuspal position continuing for more than 6 months without evidence of physical occlusal discrepancy. The problem often occurs after occlusal intervention by dental care. Although various dental treatments (e. g. occlusal adjustment, orthodontic treatment and prosthetic reconstruction) are attempted to solve occlusal dysesthesia, they rarely reach a satisfactory result, neither for patients nor dentists. In Japan, these symptoms are defined by the term "Occlusal discomfort syndrome" (ODS). The aim of this study was to investigate the characteristics of ODS with the simple occlusal sensory perceptive and discriminative test. Twenty-one female dental patients with ODS (mean age 55.8 ± 19.2 years) and 21 age- and gender-matched dental patients without ODS (mean age 53.1 ± 16.8 years) participated in the study. Upon grinding occlusal registration foils that were stacked to different thicknesses, participants reported the thicknesses at which they recognized the foils (recognition threshold) and felt discomfort (discomfort threshold). Although there was no significant difference in occlusal recognition thresholds between the two patient groups, the discomfort threshold was significantly smaller in the patients with ODS than in those without ODS. Moreover, the recognition threshold showed an age-dependent increase in patients without ODS, whereas it remained comparable between the younger (patient subgroups with ODS. These results suggest that occlusal discomfort threshold rather than recognition threshold is an issue in ODS. The foil grinding procedure is a simple and useful method to evaluate occlusal perceptive and discriminative abilities in patients with ODS.

One-step reconstruction of the right inferior hepatic veins using auto-venous grafts in living-donor liver transplantation.

Science.gov (United States)

Ikegami, Toru; Shirabe, Ken; Yoshiya, Shohei; Soejima, Yuji; Yoshizumi, Tomoharu; Uchiyama, Hideaki; Toshima, Takeo; Motomura, Takashi; Maehara, Yoshihiko

2013-07-01

Reconstruction of the right inferior hepatic vein (RIHV) presents a major technical challenge in living donor liver transplantation (LDLT) using right lobe grafts. We studied 47 right lobe LDLT grafts with RIHV revascularization, comparing one-step reconstruction, performed post-May 2007 (n = 16), with direct anastomosis, performed pre-May 2007 (n = 31). In the one-step reconstruction technique, the internal jugular vein (n = 6), explanted portal vein (n = 5), inferior vena cava (n = 3), and shunt vessels (n = 2) were used as venous patch grafts for unifying the right hepatic vein, RIHVs, and middle hepatic vein tributaries. By 6 months after LDLT, there was no case of occlusion of the reconstructed RIHVs in the one-step reconstruction group, but a cumulative occlusion rate of 18.2 % in the direct anastomosis group. One-step reconstruction required a longer cold ischemic time (182 ± 40 vs. 115 ± 63, p one-step reconstruction and 83.9 % with direct anastomosis, respectively. One-step reconstruction of the RIHVs using auto-venous grafts is an easy and feasible technique promoting successful right lobe LDLT.

Defining degree of aortic occlusion for partial-REBOA: A computed tomography study on large animals.

Science.gov (United States)

Reva, Viktor A; Matsumura, Yosuke; Samokhvalov, Igor M; Pochtarnik, Alexander A; Zheleznyak, Igor S; Mikhailovskaya, Ekaterina M; Morrison, Jonathan J

2018-04-20

Partial resuscitative endovascular balloon occlusion of the aorta (P-REBOA) is a modified REBOA technique designed to help ameliorate ischemia-reperfusion injury. The balloon is partially deflated, allowing a proportion of aortic flow distal to the balloon. The aim of this study is to use an ovine model of haemorrhagic shock to correlate the degree of occlusion to several hemodynamic indices. Six sheep weighing 35-46 kg underwent a controlled venous haemorrhage inside a CT scanner until the systolic arterial pressure (AP) dropped to fashion (proximal: r 2  = 0.85, p trend (r 2  = 0.90, p < 0.001). The relationship between percentage occlusion and IBP was sigmoid. MAP values became significantly different at 40-49% occlusion and more (p < 0.01). Furthermore, a drop in the distal pulse pressure from 7.0 (5.5-16.5) to 2.0 (1.5-5.0) mmHg was observed at 80% occlusion. All animals had femoral pulse pressure <5 mmHg at 80% of occlusion and more, which also coincided with the observed loss of pulsatility of the femoral wave-form. Serial CT angiography at an ovine model of haemorrhagic shock demonstrates a correlation between the femoral MAP, F/C pressure gradient and degree of zone I P-REBOA during the staged partial aortic occlusion. These parameters should be considered potential parameters to define the degree of P-REBOA during animal research and clinical practice. Copyright © 2018 Elsevier Ltd. All rights reserved.

Oral contraceptive pills: A risk factor for retinal vascular occlusion in in-vitro fertilization patients

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Rohina S Aggarwal

2013-01-01

Full Text Available Retinal vascular occlusion is the most common cause of retinopathy leading to severe visual loss in all age groups. Central retinal vein occlusion (CRVO is usually seen in older age group and is often associated with systemic vascular diseases. Although the exact cause and effect relationship has not been proven, central retinal vein occlusion has been associated with various systemic pathological conditions, hence a direct review of systems toward the various systemic and local factors predisposing the central retinal vein occlusion is advocated. We describe the development of central retinal venous occlusion with associated cystoid macular edema (CME in two healthy infertile women who were recruited for in vitro fertilization cycle for infertility. Predisposing risk factors associated with central retinal vein occlusion are obesity, sedentary life style, smoking, and some systemic diseases such as hyperlipidemia, hypertension, associated autoimmune disorders e.g., antiphospholipid antibody syndrome, lupus, diabetes mellitus, cardiovascular disorders, bleeding or clotting disorders, vasculitis, closed-head trauma, alcohol consumption, primary open-angle glaucoma or angle-closure glaucoma.In our patients, they were ruled out afterdoing allpertaining investigations. The cases were managed with further avoidance of oral contraceptives and intra-vitreal injections of Bevacizumab (Avastin, an anti-vascular endothelial growth factor (anti-VEGF drug and Triamcinolone acetonide (a long acting synthetic steroid. Hence, even if no systemic diseases are detected. Physical examinations are recommended periodically for young women on oral contraceptive pills.

Transcatheter therapy in partially abnormal pulmonary venous return with additional drainage to the left atrium.

Science.gov (United States)

Luciano, Debora; Laux, Daniela; Boudjemline, Younes; Hascoët, Sébastien; Lusson, Jean-René; Sorensen, Clio; Ovaert, Caroline; Kreitmann, Bernard; Van Praagh, Richard; Fraisse, Alain

2013-12-10

A persistent anastomosis between the pulmonary veins that connect with the left atrium and the systemic vein that drains into the right atrium has occasionally been reported. We report characteristics and transcatheter therapy in partially abnormal pulmonary venous return with additional drainage to the left atrium. We retrospectively studied such patients in 5 institutions. Ten patients (6 girls) presented at a median age of 8 (0.1 to 54) years with 2 anatomic types: 8 vertical vein types with drainage of the left upper lobe to the innominate vein via a large vertical vein (left superior cardinal vein) and to the left atrium via the left upper pulmonary vein; and 2 scimitar vein (SV) types with drainage of the right middle and lower pulmonary veins into the inferior vena cava and to the left atrium via an anomalous connecting vein. Associated malformations were aortic coarctation (n=2) and secundum atrial septal defects (n=3). Two patients of the vertical vein type were operated. Transcatheter occlusion of the abnormal pulmonary venous return was performed in 7 cases, associated with occlusion of systemic arterial supply (n=2), secundum atrial septal closure (n=2), left upper pulmonary vein stenosis stenting (n=1), and coarctation stenting (n=1). Including previously published cases, 18 patients (13 vertical veins and 5 scimitar veins) underwent transcatheter repair. Patients over 40 years of age tend to be symptomatic at presentation (p=0.056). In partially abnormal pulmonary venous return with dual drainage, transcatheter therapy can be offered in the majority of patients. © 2013.

Does partial occlusion promote normal binocular function?

Science.gov (United States)

Li, Jingrong; Thompson, Benjamin; Ding, Zhaofeng; Chan, Lily Y L; Chen, Xiang; Yu, Minbin; Deng, Daming; Hess, Robert F

2012-10-03

There is growing evidence that abnormal binocular interactions play a key role in the amblyopia syndrome and represent a viable target for treatment interventions. In this context the use of partial occlusion using optical devices such as Bangerter filters as an alternative to complete occlusion is of particular interest. The aims of this study were to understand why Bangerter filters do not result in improved binocular outcomes compared to complete occlusion, and to compare the effects of Bangerter filters, optical blur and neutral density (ND) filters on normal binocular function. The effects of four strengths of Bangerter filters (0.8, 0.6, 0.4, 0.2) on letter and vernier acuity, contrast sensitivity, stereoacuity, and interocular suppression were measured in 21 observers with normal vision. In a subset of 14 observers, the partial occlusion effects of Bangerter filters, ND filters and plus lenses on stereopsis and interocular suppression were compared. Bangerter filters did not have graded effect on vision and induced significant disruption to binocular function. This disruption was greater than that of monocular defocus but weaker than that of ND filters. The effect of the Bangerter filters on stereopsis was more pronounced than their effect on monocular acuity, and the induced monocular acuity deficits did not predict the induced deficits in stereopsis. Bangerter filters appear to be particularly disruptive to binocular function. Other interventions, such as optical defocus and those employing computer generated dichoptic stimulus presentation, may be more appropriate than partial occlusion for targeting binocular function during amblyopia treatment.

Near-infrared spectroscopy during stagnant ischemia estimates central venous oxygen saturation and mixed venous oxygen saturation discrepancy in patients with severe left heart failure and additional sepsis/septic shock

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Mo?ina, Hugo; Podbregar, Matej

2010-01-01

Introduction Discrepancies of 5-24% between superior vena cava oxygen saturation (ScvO2) and mixed venous oxygen saturation (SvO2) have been reported in patients with severe heart failure. Thenar muscle tissue oxygenation (StO2) measured with near-infrared spectroscopy (NIRS) during arterial occlusion testing decreases slower in sepsis/septic shock patients (lower StO2 deoxygenation rate). The StO2 deoxygenation rate is influenced by dobutamine. The aim of this study was to determine the rela...

Occlusal stability.

Science.gov (United States)

Wiens, Jonathan P; Priebe, Jennifer W

2014-01-01

Occlusion is the foundation for clinical success in fixed, removable, and implant prosthodontic treatment. Understanding those principles is critical when restoring a patient's occlusion. Many philosophies, devices, and theories of occlusion have evolved based on anecdotal clinical observations and applied geometric perceptions. The literature has reported these classic and contemporary occlusal concepts. As evidence-based dentistry emerged, it championed scrutiny of previously held beliefs, resulting in the abandonment of many pragmatic, yet beneficial occlusal procedures. The impetus toward scientific discovery, whereby factual information might be universally applied in dental education and clinical practice, has renewed interest in occlusal studies. Copyright © 2014 Elsevier Inc. All rights reserved.

Portal vein stenting for delayed jejunal varix bleeding associated with portal venous occlusion after hepatoiliary and pancreatic surgery

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Hyun, Dong Ho; Park, Kwang Bo; Cho, Sung Ki; Park, Hong Suk; Shin, Sung Wook; Choo, Sung Wook; Do, Young Soo; Choo, In Wook; Choi, Dong Wook [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2017-09-15

The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method. All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred. Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery.

Portal vein stenting for delayed jejunal varix bleeding associated with portal venous occlusion after hepatoiliary and pancreatic surgery

International Nuclear Information System (INIS)

Hyun, Dong Ho; Park, Kwang Bo; Cho, Sung Ki; Park, Hong Suk; Shin, Sung Wook; Choo, Sung Wook; Do, Young Soo; Choo, In Wook; Choi, Dong Wook

2017-01-01

The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method. All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred. Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery

Continuous Blood Glucose Monitoring May Detect Carotid Occlusion Intolerance during Carotid Artery Stenting.

Science.gov (United States)

Hiramatsu, Ryo; Furuse, Motomasa; Yagi, Ryokichi; Ohmura, Tomohisa; Ohnishi, Hiroyuki; Ikeda, Naokado; Nonoguchi, Naosuke; Kawabata, Shinji; Miyachi, Shigeru; Kuroiwa, Toshihiko

2018-02-05

The frequency of the occurrence of adverse events associated with carotid artery stenting (CAS) is usually low, but serious adverse events such as cerebral hyperperfusion syndrome (CHS) may occur. Real-time monitoring is ideal for the early detection of adverse events during the surgical procedure. This study aimed to evaluate continuous blood glucose (BG) monitoring for the detection of adverse events during CAS. Forty patients undergoing scheduled CAS were prospectively enrolled. An artificial pancreas was used for continuous BG monitoring (once per minute), using venous blood extracted at a rate of 2 mL/hr during CAS. The primary endpoint was a correlation between BG change and adverse events. CAS was discontinued in 1 patient, and BG was not measured in 5 patients (12.5%) because of the inability to extract blood. Among 34 evaluable patients, no patient developed CHS, but 3 patients (9%) experienced carotid occlusion intolerance. During CAS, BG was significantly higher in patients with carotid occlusion intolerance (median: 5 mg/dL) than in patients without carotid occlusion intolerance (median: 0 mg/dL) (P = 0.0221). A cutoff BG value ≥4 mg/dL during CAS showed 50% sensitivity and 100% specificity for the detection of carotid occlusion intolerance. There was no significant correlation between BG change and other adverse events. BG elevation may help detect carotid occlusion intolerance although it is still unknown whether BG monitoring can detect CHS. Further studies should validate that a cutoff BG elevation value of ≥4 mg/dL during CAS indicates carotid occlusion intolerance. Copyright © 2018 Elsevier Inc. All rights reserved.

Handling Occlusions for Robust Augmented Reality Systems

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Maidi Madjid

2010-01-01

Full Text Available Abstract In Augmented Reality applications, the human perception is enhanced with computer-generated graphics. These graphics must be exactly registered to real objects in the scene and this requires an effective Augmented Reality system to track the user's viewpoint. In this paper, a robust tracking algorithm based on coded fiducials is presented. Square targets are identified and pose parameters are computed using a hybrid approach based on a direct method combined with the Kalman filter. An important factor for providing a robust Augmented Reality system is the correct handling of targets occlusions by real scene elements. To overcome tracking failure due to occlusions, we extend our method using an optical flow approach to track visible points and maintain virtual graphics overlaying when targets are not identified. Our proposed real-time algorithm is tested with different camera viewpoints under various image conditions and shows to be accurate and robust.

Case Report of Optic Disc Drusen with Simultaneous Peripapillary Subretinal Hemorrhage and Central Retinal Vein Occlusion

Directory of Open Access Journals (Sweden)

David Zhiwei Law

2014-01-01

Full Text Available A 52-year-old Chinese gentleman presented with right eye floaters and photopsia over one week. His visual acuities were 20/20 bilaterally. Posterior segment examination showed a right eye swollen optic disc and central retinal vein occlusion (CRVO associated with an area of subretinal hemorrhage adjacent to the optic disc. Fundus fluorescein (FA and indocyanine green angiographies (ICGA of the right eye did not demonstrate choroidal neovascularization (CNV, polypoidal choroidal vasculopathy (PCV, or retinal ischemia. Ultrasound B-scan revealed optic disc drusen (ODD. In view of good vision and absence of CNV, he was managed conservatively with spontaneous resolution after two months. Commonly, ODD may directly compress and mechanically rupture subretinal vessels at the optic disc, resulting in peripapillary subretinal hemorrhage, as was likely the case in our patient. Mechanical impairment of peripapillary circulation also results in retinal ischemia and may trigger the development of choroidal neovascularization (CNV and/or polypoidal choroidal vasculopathy (PCV, leading to subretinal haemorrhage. Compromise in central venous outflow with increased retinal central venous pressure from the direct mechanical effects of enlarging ODD results in central retinal vein occlusion (CRVO. Patients with subretinal hemorrhage and CRVO from ODD should be monitored closely for the development of potentially sight-threatening complications.

Self care of patients with chronic venous ulcers in the home environment.

Directory of Open Access Journals (Sweden)

Thiago Gonçalves do Nascimento Piropo

2012-01-01

Full Text Available The venous ulcer is a skin lesion that affects the lower third of the legs. Is associated with chronic venous insufficiency, is the leading cause of ulcers of the lower limbs. Can interfere with the quality of life of patients, because it generates negative repercussions on social and economic sphere. The aim of this study was to identify self-care in the home environment of patients with venous ulcers, to assess the occurrence of alternative therapy use and verifythe involvement of domestic trauma. Methodologically, this study takes a quantitative and qualitative analytical cross-sectional held at the Clinical School of Physiotherapy, State University of Southwest Bahia / UESB / Jequié-BA, from January 2007 to September 2008. Data were collected through a questionnaire and semi-structured interviews. The results showed that 100% of the participants played self care of their injuries, including with respect to occlusion and bandages when needed. However, 6.25% said they had not received adequate information to perform self-care. Concluded that it is necessary to interact and produce a mechanism between education and health assistance for the development of the practice of self-care in family life at home.

Central venous pressure and mean circulatory filling pressure in the dogfish Squalus acanthias: adrenergic control and role of the pericardium.

Science.gov (United States)

Sandblom, Erik; Axelsson, Michael; Farrell, Anthony P

2006-11-01

Subambient central venous pressure (Pven) and modulation of venous return through cardiac suction (vis a fronte) characterizes the venous circulation in sharks. Venous capacitance was estimated in the dogfish Squalus acanthias by measuring the mean circulatory filling pressure (MCFP) during transient occlusion of cardiac outflow. We tested the hypothesis that venous return and cardiac preload can be altered additionally through adrenergic changes of venous capacitance. The experiments involved the surgical opening of the pericardium to place a perivascular occluder around the conus arteriosus. Another control group was identically instrumented, but lacked the occluder, and was subjected to the same pharmacological protocol to evaluate how pericardioectomy affected cardiovascular status. Routine Pven was negative (-0.08+/-0.02 kPa) in control fish but positive (0.09+/-0.01 kPa) in the pericardioectomized group. Injections of 5 microg/kg body mass (Mb) of epinephrine and phenylephrine (100 microg/kg Mb) increased Pven and MCFP, whereas isoproterenol (1 microg/kg Mb) decreased both variables. Thus, constriction and relaxation of the venous vasculature were mediated through the respective stimulation of alpha- and beta-adrenergic receptors. Alpha-adrenergic blockade with prazosin (1 mg/kg Mb) attenuated the responses to phenylephrine and decreased resting Pven in pericardioectomized animals. Our results provide convincing evidence for adrenergic control of the venous vasculature in elasmobranchs, although the pericardium is clearly an important component in the modulation of venous function. Thus active changes in venous capacitance have previously been underestimated as an important means of modulating venous return and cardiac performance in this group.

Venous Access Ports: Indications, Implantation Technique, Follow-Up, and Complications

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Walser, Eric M., E-mail: walser.eric@mayo.edu [Mayo Clinic, Department of Radiology (United States)

2012-08-15

The subcutaneous venous access device (SVAD or 'port') is a critical component in the care of patients with chronic disease. The modern SVAD provides reliable access for blood withdrawal and medication administration with minimal disruption to a patient's lifestyle. Because of improved materials and catheter technology, today's ports are lighter and stronger and capable of high-pressure injections of contrast for cross-sectional imaging. The majority of SVAD placement occurs in interventional radiology departments due to their ability to provide this service at lower costs, lower, complication rates, and greater volumes. Port-insertion techniques vary depending on the operator, but all consist of catheter placement in the central venous circulation followed by subcutaneous pocket creation and port attachment to the catheter with fixation and closure of the pocket. Venous access challenges occasionally occur in patients with central vein occlusions, necessitating catheterization of collateral veins or port placement in alternate locations. Complications of SVADs include those associated with the procedure as well as short- (<30 days) and long-term problems. Procedural and early complications are quite rare due to the near-universal use of real-time ultrasound guidance for vein puncture, but they can include hematoma, catheter malposition, arrhythmias, and pneumothorax. Late problems include both thrombotic complications (native venous or port-catheter thrombosis) and infections (tunnel or pocket infections or catheter-associated bloodstream infections). Most guidelines suggest that 0.3 infections/1000 catheter days is an appropriate upper threshold for the insertion of SVADs.

Balloon occlusion of the internal carotid artery in 40 cases of giant intracavernous aneurysm: Technical aspects, cerebral monitoring, and results

International Nuclear Information System (INIS)

Vazquez Anon, V.; Aymard, A.; Gobin, Y.P.; Casasco, A.; Rueffenacht, D.; Khayata, M.H.; Merland, J.J.; Abizanda, E.; Redondo, A.

1992-01-01

We have studied the results of carotid occlusion in the treatment of giant intracavernous carotid artery (ICA) aneurysms in 40 patients. Clinical, angiographic, Doppler and cerebral blood flow (CBF) criteria for tolerance of occlusion are discussed. The patients had headaches (47.5%), cranial nerve compression (87.5%), decreased visual acuity (20%), ruptured aneurysm (15%) and 5% were asymptomatic. Balloon occlusion tests were performed under light sedation anaesthesia; a successful test required perfect clinical tolerance and adequate angiographic collateral circulation in arterial, parenchymatous, and venous phases. Additional criteria included xenon 133 CBF measurements, and transcranial Doppler sonography of the middle cerebral artery. According to these criteria, 5 patients did not tolerate test occlusion and required an extra-intracranial (EC-IC) bypass. Mean follow-up was 4.7 years. All patients were radiologically cured of their aneurysm, and in 35 the symptoms resolved, although 3 had persistent ocular motor nerve palsies, and in 4 visual defects were unchanged. Complications were 1 permament and 3 transient neurological deficits. Balloon occlusion of the ICA is an effective, reliable form of treatment for intracavernous giant aneurysm and should replace surgical ligation of the cervical carotid artery. With CBF or Doppler monitoring, the risk of neurological deficit is diminished. EC-IC bypass prior to ICA occlusion is indicated if test occlusion is not tolerated. (orig.)

Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy.

Science.gov (United States)

McLeod, David; Beatty, Stephen

2015-11-01

The rationale behind hyperacute fibrinolytic therapy for cerebral and retinal arterial occlusion is to rescue ischaemic cells from irreversible damage through timely restitution of tissue perfusion. In cerebral stroke, an anoxic tissue compartment (the "infarct core") is surrounded by a hypoxic compartment (the "ischaemic penumbra"). The latter comprises electrically-silent neurons that undergo delayed apoptotic cell death within 1-6 h unless salvaged by arterial recanalisation. Establishment of an equivalent hypoxic compartment within the inner retina following central retinal artery occlusion (CRAO) isn't widely acknowledged. During experimental CRAO, electroretinography reveals 3 oxygenation-based tissue compartments (anoxic, hypoxic and normoxic) that contribute 32%, 27% and 41% respectively to the pre-occlusion b-wave amplitude. Thus, once the anoxia survival time (≈2 h) expires, the contribution from the infarcted posterior retina is irreversibly extinguished, but electrical activity continues in the normoxic periphery. Inbetween these compartments, an annular hypoxic zone (the "penumbra obscura") endures in a structurally-intact but functionally-impaired state until retinal reperfusion allows rapid recovery from electrical silence. Clinically, residual circulation of sufficient volume flow rate generates the heterogeneous fundus picture of "partial" CRAO. Persistent retinal venous hypoxaemia signifies maximal extraction of oxygen by an enduring "polar penumbra" that permeates or largely replaces the infarct core. On retinal reperfusion some days later, the retinal venous oxygen saturation reverts to normal and vision improves. Thus, penumbral inner retina, marginally oxygenated by the choroid or by residual circulation, isn't at risk of delayed apoptotic infarction (unlike hypoxic cerebral cortex). Emergency fibrinolytic intervention is inappropriate, therefore, once the duration of CRAO exceeds 2 h. Copyright © 2015 Elsevier Ltd. All rights reserved.

Temporary Arterial Balloon Occlusion as an Adjunct to Yttrium-90 Radioembolization

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Hagspiel, Klaus D., E-mail: kdh2n@virginia.edu [University of Virginia Health System, Department of Radiology and Medical Imaging (United States); Nambiar, Ashwin, E-mail: uvashwin@gmail.com [SUNY Downstate Medical Center, Department of Radiology (United States); Hagspiel, Lauren M., E-mail: lmh4gg@virginia.edu [University of Virginia, College of Arts and Sciences (United States); Ahmad, Ehab Ali, E-mail: ehabradiodiagnosis@yahoo.com [Minia University, Department of Radiology (Egypt); Bozlar, Ugur, E-mail: ubozlar@yahoo.com [Gulhane Military Medical Academy, Department of Radiology (Turkey)

2013-06-15

Purpose. This study was designed to describe the technique of arterial occlusion using a temporary occlusion balloon system as an alternative to coil occlusion during Yttrium-90 radioembolization of hepatic tumors. Methods. Review of charts, angiography, and follow-up imaging studies of consecutive patients undergoing oncological embolization procedures in which a HyperForm system (ev3 Neurovascular, Irvine, CA) was used. Intraprocedural target vessel occlusion and patency of the target vessel on follow-up were recorded. Clinical data and Bremsstrahlung scans were reviewed for evidence of nontarget embolization. Results. Four radioembolization procedures were performed in three patients (all female, age 48-54 (mean 52) years). Five arteries were temporarily occluded (three gastroduodenal arteries, one right gastric artery, and one cystic artery). All radioembolization procedures were successfully completed. Follow-up imaging (either digital subtraction angiography (DSA) or computed tomography angiography (CTA)) was available for all patients between 28-454 (mean 183) days following the procedure, demonstrating all five vessels to be patent. No clinical or imaging evidence for nontarget embolization was found. Conclusions. Temporary balloon occlusion of small and medium-sized arteries during radioembolization allows safe therapy with preserved postprocedural vessel patency on early and midterm follow-up.

Gestational related changes in the deep venous system of the lower limb on light reflection rheography in pregnancy and the puerperium

Energy Technology Data Exchange (ETDEWEB)

Calderwood, C.J. [St John' s Hospital, Livingston and Simpson Centre for Reproductive Health, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom)], E-mail: catherine.calderwood@luht.scot.nhs.uk; Jamieson, R. [Princess Royal Maternity Unit, Glasgow Royal Infirmary, Glasgow (United Kingdom); Greer, I.A. [Hull York Medical School, University of York, York (United Kingdom)

2007-12-15

Objective: To assess whether light reflection rheography testing is affected by the changes that occur in the deep venous system of the lower limb in pregnancy and the puerperium. Methods: Twenty five women with a singleton pregnancy were recruited to undergo duplex Doppler ultrasound examinations of the common femoral vein to measure the vessel diameter and the blood flow velocity. Light reflection rheography testing was subsequently performed and the rate of venous emptying in the lower limb calculated. Serial measurements using both techniques were made at 15, 28, 36 weeks, and term gestation and at 2 days and 6 weeks postpartum. Results: Duplex Doppler ultrasound confirmed that there is progressive dilatation of the deep venous system in pregnancy, which reaches a maximum at term and reverses after delivery. There is an accompanying reduction in blood flow velocity, which reaches a nadir at term and increases after delivery. The rate of venous emptying as measured by light reflection rheography decreases with increasing gestation, but did not fall to a level consistent with venous occlusion by a deep venous thrombosis. Conclusions: Light reflection rheography has been shown to provide reliable results in pregnancy and the puerperium. Therefore, it is a potential tool for screening for deep venous thrombosis in this population.

Gestational related changes in the deep venous system of the lower limb on light reflection rheography in pregnancy and the puerperium

International Nuclear Information System (INIS)

Calderwood, C.J.; Jamieson, R.; Greer, I.A.

2007-01-01

Objective: To assess whether light reflection rheography testing is affected by the changes that occur in the deep venous system of the lower limb in pregnancy and the puerperium. Methods: Twenty five women with a singleton pregnancy were recruited to undergo duplex Doppler ultrasound examinations of the common femoral vein to measure the vessel diameter and the blood flow velocity. Light reflection rheography testing was subsequently performed and the rate of venous emptying in the lower limb calculated. Serial measurements using both techniques were made at 15, 28, 36 weeks, and term gestation and at 2 days and 6 weeks postpartum. Results: Duplex Doppler ultrasound confirmed that there is progressive dilatation of the deep venous system in pregnancy, which reaches a maximum at term and reverses after delivery. There is an accompanying reduction in blood flow velocity, which reaches a nadir at term and increases after delivery. The rate of venous emptying as measured by light reflection rheography decreases with increasing gestation, but did not fall to a level consistent with venous occlusion by a deep venous thrombosis. Conclusions: Light reflection rheography has been shown to provide reliable results in pregnancy and the puerperium. Therefore, it is a potential tool for screening for deep venous thrombosis in this population

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.

Interventional radiologic placement of tunneled central venous catheters : results and complications in 557 cases

Energy Technology Data Exchange (ETDEWEB)

Kim, Chan Kyo; Do, Young Soo; Paik, Chul H. [Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)] (and others)

1999-05-01

To evaluate prospectively the results of interventional radiologic placement of tunneled central venous catheters, and subsequent complications. Between April 1997 and April 1998, a total of 557 tunneled central venous catheters were percutaneously placed in 517 consecutive patients in an interventional radiology suite. The indications were chemotherapy in 533 cases, total parenteral nutrition in 23 and transfusion in one. Complications were evaluated prospectively by means of a chart review, chest radiography, central vein angiography and blood/catheter culture. The technical success rate for tunneled central venous catheter placement was 100% (557/557 cases). The duration of catheter placement ranged from 4 to 356 (mean, 112{+-}4.6) days; Hickman catheters were removed in 252 cases during follow-up. Early complications included 3 cases of pneumothorax(0.5%), 4 cases of local bleeding/hematoma(0.7%), 2 cases of primary malposition(0.4%), and 1 case of catheter leakage(0.2%). Late complications included 42 cases of catheter-related infection(7.5%), 40 cases of venous thrombosis (7.2%), 18 cases of migration (3.2%), 5 cases of catheter / pericatheter of occlusion(0.8%), and 1 case of pseudoaneurysm(0.2%). The infection rate and thrombosis rate per 1000 days were 1.57 and 1.50, respectively. The technical success rate of interventional radiologic placement of tunneled central venous catheters was high. In comparison to conventional surgical placement, it is a more reliable method and leads to fewer complications.

Deep venous thrombosis in the lower extremity: catheter-directed thrombolysis

Energy Technology Data Exchange (ETDEWEB)

Roh, Byung Suk; Kim, En A; Park, Ki Han; Yoon, Kwon Ha; So, Byung Jun; Juhng, Seon Kwan; Won, Jin Jong [School of Medicine, Wonkwang University, Iksan (Korea, Republic of)

2000-09-01

To evaluate the efficacy of catheter-directed thrombolysis in treating symptomatic deep venous thrombosis (DVT) in lower limbs. Twenty-six consecutive patients (16 male and 10 female; mean age, 55 years) with lower extremity DVT underwent thrombolytic therapy. The duration of symptoms was 1-90 (mean, 17) days: 20 days or less in 16 cases (acute DVT) and less than 20 days in ten (chronic DVT). Catheter-directed infusions of urokinase were administered via ipsilateral popliteal veins, and angioplasty or stent placement was performed after the thrombolytic procedure. Oral medication of warfarin continued for six months, and for the evaluation of venous patency, follow-up ultrasonography was performed. The total dose of infused urokinase was 1,750,000-10,000,000 (mean 4,84,000) IU, and the total procedural time was 25-115 (mean, 64) hours. Lysis was complete in 16 cases (62%, all acute DVT), partial in five (19%, chronic DVT), and failed in five (19%, chronic DVT). Eight patients with venous stenosis and two with occlusion were treated by means of angioplasty (n=3D4) or Wallstent placement (n=3D6). Minor bleeding occurred in six cases and major complications in two (one of pulmonary embolism, and one of multiorgan failure). Catheter-directed thrombolysis with urokinase is effective for the treatment of DVT in lower limbs. (author)

Deep venous thrombosis in the lower extremity: catheter-directed thrombolysis

International Nuclear Information System (INIS)

Roh, Byung Suk; Kim, En A; Park, Ki Han; Yoon, Kwon Ha; So, Byung Jun; Juhng, Seon Kwan; Won, Jin Jong

2000-01-01

To evaluate the efficacy of catheter-directed thrombolysis in treating symptomatic deep venous thrombosis (DVT) in lower limbs. Twenty-six consecutive patients (16 male and 10 female; mean age, 55 years) with lower extremity DVT underwent thrombolytic therapy. The duration of symptoms was 1-90 (mean, 17) days: 20 days or less in 16 cases (acute DVT) and less than 20 days in ten (chronic DVT). Catheter-directed infusions of urokinase were administered via ipsilateral popliteal veins, and angioplasty or stent placement was performed after the thrombolytic procedure. Oral medication of warfarin continued for six months, and for the evaluation of venous patency, follow-up ultrasonography was performed. The total dose of infused urokinase was 1,750,000-10,000,000 (mean 4,84,000) IU, and the total procedural time was 25-115 (mean, 64) hours. Lysis was complete in 16 cases (62%, all acute DVT), partial in five (19%, chronic DVT), and failed in five (19%, chronic DVT). Eight patients with venous stenosis and two with occlusion were treated by means of angioplasty (n=3D4) or Wallstent placement (n=3D6). Minor bleeding occurred in six cases and major complications in two (one of pulmonary embolism, and one of multiorgan failure). Catheter-directed thrombolysis with urokinase is effective for the treatment of DVT in lower limbs. (author)

The collateral venous system in late pregnancy: A systematic review of the literature.

Science.gov (United States)

Humphries, Aimee; Stone, Peter; Mirjalili, S Ali

2017-11-01

Recent literature has reported an association between maternal supine sleep position and stillbirth during late pregnancy. In this position the gravid uterus almost completely obstructs the inferior vena cava. A small number of women experience supine hypotension, thought to be due in part to inadequate collateral venous circulation. The aim of this paper is to review the literature describing the anatomy of the collateral venous system and in particular the azygos system, the abdominal portion of which has not been well studied. A systematic review was conducted using the electronic databases: Medline, Embase, Scopus, and Google Scholar. Relevant anatomical and radiological literature concerning the azygos system in particular was reviewed. The search was limited to adult human studies only. The collateral venous system can be divided into superficial, intermediate and deep systems. The azygos system in particular provides immediate collateral venous circulation in the event of acute inferior vena caval obstruction. The abdominal portion of this pathway, including the ascending lumbar vein, has not been well studied and there are certain variations that can render it ineffective. In conclusion, the collateral venous system provides an alternative route for blood to flow back to the systemic circulation when acute occlusion of the inferior vena cava occurs in the supine position during late pregnancy. However, certain anatomical variations can render this pathway ineffective, and this could have implications for the development of supine hypotension and stillbirth in late pregnancy. Clin. Anat. 30:1087-1095, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

CT imaging of hepatic veno-occlusive disease (an analysis 14 cases)

International Nuclear Information System (INIS)

Zhang Guohua; Kong Azhao; Fang Junwei; Chen Yuejing; Zheng Weiliang; Dong Danjun; Zhang Shizheng

2006-01-01

Objective: To probe imaging characteristics of the hepatic veno-occlusive disease (VOD) based on clinical features and abdomen CT findings. Methods: Fourteen patients including 6 male and 8 female aged from 41 to 73 years were enrolled in this study. They all had previous trauma history and notoginseng was given as herbal remedy. Dynamic enhanced CT and color Dopplor ultrasound examinations were routinely used. Two of them received venous angiography and four cases were pathologically proved as VOD after CT guided needle biopsy. Results: Hepatic swelling and ascites were found on plain CT scan. Diffuse patchy areas without enhancement indicative of poorly hepatic perfusion were found. Hepatic veins were compressed and became thin, and inferior vena cava was flat and narrow without distal dilation or collateral circulation. No obstruction of hepatic veins and inferior vena cava was found on ultrasound and venography. Conclusion: Dynamic enhanced CT is highly valuable for early assessing VOD and imaging features of venous hepatic congestion found on CT was strongly suggestive of VOD if there's previous history of treatment of gynura segetum. (authors)

Object tracking by occlusion detection via structured sparse learning

KAUST Repository

Zhang, Tianzhu

2013-06-01

Sparse representation based methods have recently drawn much attention in visual tracking due to good performance against illumination variation and occlusion. They assume the errors caused by image variations can be modeled as pixel-wise sparse. However, in many practical scenarios these errors are not truly pixel-wise sparse but rather sparsely distributed in a structured way. In fact, pixels in error constitute contiguous regions within the object\\'s track. This is the case when significant occlusion occurs. To accommodate for non-sparse occlusion in a given frame, we assume that occlusion detected in previous frames can be propagated to the current one. This propagated information determines which pixels will contribute to the sparse representation of the current track. In other words, pixels that were detected as part of an occlusion in the previous frame will be removed from the target representation process. As such, this paper proposes a novel tracking algorithm that models and detects occlusion through structured sparse learning. We test our tracker on challenging benchmark sequences, such as sports videos, which involve heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that our tracker consistently outperforms the state-of-the-art. © 2013 IEEE.

Patients with restored occlusions. Part III: The effect of occlusal splint therapy and occlusal adjustments on TMJ dysfunction.

Science.gov (United States)

Lederman, K H; Clayton, J A

1983-07-01

An earlier study of 50 patients with occlusions restored by fixed partial dentures indicated a high percent (68%) of TMJ dysfunction. Occlusal interferences can play a significant role in causing TMJ dysfunction. To determine the significance of occlusal interferences, occlusal splints were placed in 10 of these restored patients who had moderate to severe dysfunction. The PRI was used to detect the presence or absence of TMJ dysfunction. The PRI TMJ dysfunction scores were reduced in all 10 patients after use of the occlusal splint. Five of the patients achieved reproducible tracings (no TMJ dysfunction) during the experiment time of 7 months. The occlusion of two patients was adjusted to eliminate the need for the occlusal splint. Patients who wore the splint 24 hours a day showed a significant (0.0004 level) reduction in TMJ dysfunction. Those patients who did not wear the splint regularly or had high levels of stress had PRI scores that varied. This finding indicates that the occlusal splint is not a treatment, as its removal permits reactivation of the occlusal interference. Resolution of dysfunction did not occur until occlusal interferences were removed. The changes in PRI scores to different dysfunction categories (none, slight, moderate, and severe) for the experimental group were significant at the 0.01 level. A control group of five patients had similar pantographic tracings but no other treatment. Their PRI scores varied, but there was no significant change in PRI scores or dysfunction categories. It was concluded that occlusal interferences were active causes of TMJ dysfunction in 10 of 36 patients in a population with restored occlusions.

Novel approach to epicardial pacemaker implantation in patients with limited venous access.

Science.gov (United States)

Costa, Roberto; Scanavacca, Mauricio; da Silva, Kátia Regina; Martinelli Filho, Martino; Carrillo, Roger

2013-11-01

Limited venous access in certain patients increases the procedural risk and complexity of conventional transvenous pacemaker implantation. The purpose of this study was to determine a minimally invasive epicardial approach using pericardial reflections for dual-chamber pacemaker implantation in patients with limited venous access. Between June 2006 and November 2011, 15 patients underwent epicardial pacemaker implantation. Procedures were performed through a minimally invasive subxiphoid approach and pericardial window with subsequent fluoroscopy-assisted lead placement. Mean patient age was 46.4 ± 15.3 years (9 male [(60.0%], 6 female [40.0%]). The new surgical approach was used in patients determined to have limited venous access due to multiple abandoned leads in 5 (33.3%), venous occlusion in 3 (20.0%), intravascular retention of lead fragments from prior extraction in 3 (20.0%), tricuspid valve vegetation currently under treatment in 2 (13.3%), and unrepaired intracardiac defects in 2 (13.3%). All procedures were successful with no perioperative complications or early deaths. Mean operating time for isolated pacemaker implantation was 231.7 ± 33.5 minutes. Lead placement on the superior aspect of right atrium, through the transverse sinus, was possible in 12 patients. In the remaining 3 patients, the atrial lead was implanted on the left atrium through the oblique sinus, the postcaval recess, or the left pulmonary vein recess. None of the patients displayed pacing or sensing dysfunction, and all parameters remained stable throughout the follow-up period of 36.8 ± 25.1 months. Epicardial pacemaker implantation through pericardial reflections is an effective alternative therapy for those patients requiring physiologic pacing in whom venous access is limited. © 2013 Heart Rhythm Society. All rights reserved.

Occlusion detection via structured sparse learning for robust object tracking

KAUST Repository

Zhang, Tianzhu

2014-01-01

Sparse representation based methods have recently drawn much attention in visual tracking due to good performance against illumination variation and occlusion. They assume the errors caused by image variations can be modeled as pixel-wise sparse. However, in many practical scenarios, these errors are not truly pixel-wise sparse but rather sparsely distributed in a structured way. In fact, pixels in error constitute contiguous regions within the object’s track. This is the case when significant occlusion occurs. To accommodate for nonsparse occlusion in a given frame, we assume that occlusion detected in previous frames can be propagated to the current one. This propagated information determines which pixels will contribute to the sparse representation of the current track. In other words, pixels that were detected as part of an occlusion in the previous frame will be removed from the target representation process. As such, this paper proposes a novel tracking algorithm that models and detects occlusion through structured sparse learning. We test our tracker on challenging benchmark sequences, such as sports videos, which involve heavy occlusion, drastic illumination changes, and large pose variations. Extensive experimental results show that our proposed tracker consistently outperforms the state-of-the-art trackers.

Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems.

Science.gov (United States)

Sharif-Kashani, Pooria; Fanney, Douglas; Injev, Val

2014-07-30

Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery.

Proximal Occlusion of Medium-Sized Vessels with the Penumbra Occlusion Device: A Study of Safety and Efficacy

Energy Technology Data Exchange (ETDEWEB)

Jambon, E.; Petitpierre, F. [Pellegrin Hospital, Department of Radiology (France); Brizzi, V.; Dubuisson, V. [Pellegrin Hospital, Department of Surgery (France); Bras, Y. Le; Grenier, N.; Cornelis, F., E-mail: cornelisfrancois@gmail.com [Pellegrin Hospital, Department of Radiology (France)

2017-02-15

PurposeTo retrospectively investigate the safety and efficacy of hybrid proximal coiling of various medium-sized vessels (4 to 8 mm) using the Penumbra Occlusion Device (POD).Materials and MethodsFrom October 2014 to February 2016, 37 proximal embolizations were performed with PODs in 36 patients (mean age: 50.8, range: 10–86; 29 male, 7 female). Vessel occlusions were achieved under fluoroscopic guidance using a 2.7 French microcatheter. Among the 36 vessels targeted, 16 were splenic arteries, 11 renal arteries, 4 mesenteric arteries, 3 arteriovenous fistulae, 1 iliac artery, and 1 gonadal vein. Intermittent follow-up angiography was performed to assess the flow for final occlusion. Outcomes and complications were assessed by clinical and/or imaging follow-up.ResultsTo produce proximal occlusion of the intended vessels, the POD was used alone in 19 embolizations (51.4 %). In 12 procedures (32.4 %), POD was used as a coil constrainer to secure the coil construct. In 6 procedures (16.2 %), additional embolic devices were used to achieve vessel occlusion after initial POD deployment. After a mean follow-up of 3.2 months, no POD migration was observed but two complications occurred (5.4 %): one post embolic syndrome and one extensive infarction with splenic abscess.ConclusionThe POD system allows safe and effective proximal embolization of medium-sized vessels in a variety of clinical settings.

Complex left profunda femoris vein to renal vein bypass for the management of progressive chronic iliofemoral occlusion.

Science.gov (United States)

Anaya-Ayala, Javier E; Adams, Matthew K; Telich-Tarriba, Jose E; Dresser, Kelly L; Ismail, Nyla; Peden, Eric K

2013-01-01

Chronic occlusions of the inferior vena cava (IVC) and iliofemoral veins are long-term sequelae of deep venous thrombosis (DVT) that can lead to postthrombotic syndrome (PTS). Patients may present with a wide spectrum of signs and symptoms, ranging from mild discomfort and swelling to severe venous hypertension and ulcerations. We report a 68-year-old man who had a history of left lower extremity DVT after a laminectomy and who developed PTS with nonhealing ulcers. The patient underwent a cross-pubic femorofemoral venous bypass that failed to improve his clinical status. After unsuccessful endovascular attempts for recanalization of the iliofemoral segment, a profunda femoris to IVC bypass was performed. The symptoms recurred 2 years later. Venography revealed restenosis at the caval anastomosis that did not resolve by endovascular means. A surgical revision was performed, and given the quality of the IVC, a jump bypass was created to the left renal vein. The swelling improved and the ulcers healed completely. Twenty-eight months after the complex reconstructions, he remains ulcer-free with mild edema controlled with stockings. Venous reconstructions remain a viable option for patients with symptomatic and recalcitrant nonmalignant obstruction of the large veins. Copyright © 2013 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

Usefulness of time-resolved projection MRA on evaluation of hemodynamics in cerebral occlusive diseases

International Nuclear Information System (INIS)

Oka, Yoshihisa; Kusunoki, Katsusuke; Nochide, Ichiro; Igase, Keiji; Harada, Hironobu; Sadamoto, Kazuhiko; Nagasawa, Kiyoshi

2001-01-01

The usefulness for evaluation of cerebral hemodynamics using time-resolved projection MRA was studied in normal volunteers and patients of cerebrovascular diseases. Six normal volunteers and ten patients with cerebrovascular occlusive diseases including 6 of IC occlusion and 4 of post EC/IC bypass surgery underwent time-resolved projection MRA on a 1.5 T clinical MRI system. Projection angiograms are acquired with 2D-fast SPGR sequence with a time resolution of approximately one image per second, 40 images being acquired consecutively before and after bolus injection Gd-DTPA. And all images were calculated by complex subtraction from the background mask in a work station. In normal volunteers, the quality of images of time-resolved projection MRA was satisfactory. The arteries from internal carotid artery through M2 segment of middle cerebral artery and all major venous systems were well portrayed. In 4 cases of IC occlusion who were assessed the collateral flow through the anterior communicating artery and posterior communicating artery, there were delayed to demonstrate the ipsilateral MCA. However, in 2 cases of IC occlusion that were assessed the collateral flow through leptomeningeal anastomosis, ipsilateral MCA and collateral circulation were not demonstrated. In all patients of post EC/IC bypass surgery, the patency of EC/IC bypass could be evaluated as properly with time-resolved projection MRA as 3D-TOF MRA. Although the temporal and spatial resolutions are insufficient, time-resolved projection MRA was power-full non-invasive method to evaluate the cerebral hemodynamics vis the basal communicating arteries in IC occlusion and identify the patency of EC/IC bypass. (author)

Comparative study of peripherally inserted central venous catheter and traditional central catheter assisted with X-ray

International Nuclear Information System (INIS)

Yu Jianchun; Wang Xiurong; Jiang Zhuming

1999-01-01

Objective: To study the feasibility, complications, mid- and long-term advantages of peripherally inserted central catheters (PICC) compared with central venous access assisted with X-ray. Methods: From Jan 1997 to Dec 1998, the authors conducted a study in 60 patients with placed PICC lines and 60 patients with central lines. Study variables included tip placement and complication rates. Results: Tere were on significant differences between PICC and CVC in the successful placement 95.0% and 88.3%, t = 1.745, P 0.19; the mean duration 13(6-98) days and 14 (7-104) days, F = 0.049, P = 0.83; the total occlusion rate 6.7% (4/60) and 5.0%(3/60), t = 0.152, P = 0.70. In PICC patients, the occlusion rate was slightly higher in 3 Fr (20-gauge) catheter (3/20, 15.0%) than in 4 Fr(18-gauge) catheters (1/20, 5.0%), t = 1.111, P=0.29. Phlebitis occurred in 5.0% of patients (3/60) and one catheter fracture was happened on the catheter hub junction (1.7%). In 3 catheter tips dislocation cases, the catheter tips were moved to the optional position assisted with X-ray image. In CVC group, pneumothorax happened in 1 case (1.7%). In 4 catheter dislocation cases, the catheters were with drawn. No catheter-related sepsis and hemo-pneumothorax happened in both group patients. Conclusions: Both PICC and CVC can be acceptable in clinical use. PICC assisted with X-ray possesses the advantages of less trauma, accurate localization preventing some possible severe complications of central venous access such as pneumothorax. The new method provides a reliable, effective venous access for mid-and long-term usage in patients receiving a variety of solutions, primarily parenteral alimentation, chemotherapy or antibiotic infusion

Inflammation and peripheral venous disease. The San Diego Population Study.

Science.gov (United States)

Cushman, M; Callas, P W; Allison, M A; Criqui, M H

2014-09-02

The inflammatory response to healing in venous thrombosis might cause vein damage and post-thrombotic syndrome. Inflammation may also be involved in venous insufficiency apart from deep-vein thrombosis. We studied the association of inflammation markers with venous insufficiency in a general population sample. We characterised 2,404 men and women in a general population cohort for peripheral venous disease and its severity using physical exam, symptom assessment, and venous ultrasound. Inflammation markers, C-reactive protein (CRP), fibrinogen, interleukin 1-beta (IL-1-beta), IL-8, IL-10, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, monocyte chemoattractant-1 (MCP-1) and vascular endothelial cell growth factor (VEGF) were compared in 352 case participants with peripheral venous disease and 352 controls with no venous abnormalities frequency matched to cases by age, sex and race. Associations were also evaluated including a subset of 108 cases of severe venous disease, as previously defined. Odds ratios (95% CI), for peripheral venous disease for biomarkers in the top quartile (adjusting for age, race, sex, body mass index and history of venous thrombosis) were 1.8 (1.1-3.0), 1.6 (1.0-2.5) and 1.5 (0.9-2.3) for CRP, fibrinogen and IL-10, respectively. Associations were larger considering cases of severe venous disease, with odds ratios for these three analytes of 2.6 (1.2-5.9), 3.1 (1.3-7.3) and 2.2 (1.1-4.4), and for IL-8: 2.4 (1.1-5.2). There was no association of IL-1-beta, ICAM-1, VCAM-1, E-selectin, MCP-1 or VEGF with overall cases or severe venous disease. In conclusion, a subset of inflammation markers were associated with increased risk of peripheral venous disease, suggesting potential therapeutic targets for treatment.

Rivaroxaban attenuates thrombosis by targeting the NF-κB signaling pathway in a rat model of deep venous thrombus.

Science.gov (United States)

Ma, Junhao; Li, Xinxi; Wang, Yang; Yang, Zhenwei; Luo, Jun

2017-12-01

Anticoagulant therapy is commonly used for the prevention and treatment of patients with deep venous thrombus. Evidence has shown that rivaroxaban is a potential oral anticoagulant drug for the acute treatment of venous thromboembolism. However, the rivaroxaban-mediated molecular mechanism involved in the progression of deep venous thrombosis has not been investigated. In the present study, we investigated the efficacy of rivaroxaban and the underlying signaling pathways in the prevention and treatment of rats with deep venous thrombosis. A rat model with deep vein thrombus formation was established and received treatment with rivaroxaban or PBS as control. The thrombin-activatable fibrinolysis inhibitor (TAFI) and plasminogen activator inhibitor-1 (PAI-1) were analyzed both in vitro and in vivo. The progression of thrombosis and stroke was evaluated after treatment with rivaroxaban or PBS. Nuclear factor-κB (NF-κB) signaling pathway in venous endothelial cells and in the rat model of deep venous thrombus was assessed. The therapeutic effects of rivaroxaban were evaluated as determined by changes in deep venous thrombosis in the rat model. Our results showed that rivaroxaban markedly inhibited TAFI and PAI-1 expression levels, neutrophils, tissue factor, neutrophil extracellular traps (NETs), myeloperoxidase and macrophages in venous endothelial cells and in the rat model of deep venous thrombus. Expression levels of ADP, PAIs, von Willebrand factor (vWF) and thromboxane were downregulated in vein endothelial cells and in serum from the experimental rats. Importantly, the incidences of inferior vena cava filter thrombus were protected by rivaroxaban during heparin-induced thrombolysis deep venous thrombosis in the rat model. We observed that activity of the NF-κB signaling pathway was inhibited by rivaroxaban in vein endothelial cells both in vitro and in vivo. Notably, immunohistology indicated that rivaroxaban attenuated deep venous thrombosis and the

Occluded Brescia-Cimino Hemodialysis Fistulas: Endovascular Treatment with Both Brachial Arterial and Venous Access Using the Pull-Through Technique

International Nuclear Information System (INIS)

Miyayama, Shiro; Matsui, Osamu; Taki, Keiichi; Minami, Tetsuya; Shinmura, Rieko; Ito, Chiharu; Takamatsu, Shigeyuki; Kobayashi, Miki; Ushiogi, Yashuyuki

2005-01-01

We retrospectively evaluated the usefulness of both arterial and venous access with the pull-through technique in endovascular treatment of totally occluded Brescia-Cimino fistulas. We treated 26 patients (17 men, 9 women; age range 43-82 years, mean age 66 years) with occluded Brescia-Cimino fistulas. First, the occluded segment was traversed from the antegrade brachial arterial access using a microcatheter-guidewire system. Second, the vein was retrogradely punctured after confirmation of all diseased segments, and a 0.014- or 0.016-inch guidewire was pulled through the venous access when the occluded segment was long. All interventions including thrombolysis, thromboaspiration, angioplasty, and stent placement were performed via the venous access. The occlusion was successfully crossed via the brachial arterial access in 23 patients (88%). In 2 patients it was done from the venous approach. In the remaining patient it was not possible to traverse the occluded segment. The pull-through technique was successful in all 19 attempts. Clinical success was achieved in 96%, the primary patency rates at 6, 12, and 18 months were 83%, 78%, and 69%, the primary assisted patency rates were 92%, 92%, and 72%, and the secondary patency rates were 92%, 92%, and 92%, respectively. Minor complications in 5 patients included venous perforation in 2 (8%), venous rupture in 1 (4%), and regional hematoma in 2 (8%). Our study suggests that endovascular treatments with both arterial and venous access using the pull-through technique are highly effective in restoring function in totally occluded Brescia-Cimino fistulas

Peripheral Venous Access Ports: Outcomes Analysis in 109 Patients

International Nuclear Information System (INIS)

Bodner, Leonard J.; Nosher, John L.; Patel, Kaushik M.; Siegel, Randall L.; Biswal, Rajiv; Gribbin, Christopher E.; Tokarz, Robert

2000-01-01

(p = 0.6). Aspiration occlusion occurred in 13 patients (11.7%). Intracatheter urokinase was infused in eight of these patients and successfully restored catheter function in all but two instances. These complication rates are comparable to or better than those reported with chest ports.Conclusion: Peripheral ports for long-term central venous access placed by interventional radiologists in the interventional radiology suite are as safe and as effective as chest ports

Parenchymal abnormalities in cerebral venous thrombosis: findings of magnetic resonance imaging and magnetic resonance angiography

International Nuclear Information System (INIS)

Ferreira, Clecia Santos; Pellini, Marcos; Boasquevisque, Edson; Souza, Luis Alberto M. de

2006-01-01

Objective: to determine the frequency and localization of parenchymal abnormalities in cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography as well as their correlation with the territory and affected venous drainage. Materials and methods: retrospective analysis (1996 to 2004) of 21 patients (3 male and 18 female) age range between 3 and 82 years (mean 40 years, median 36 years) with clinical and radiological diagnosis of cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography in 2D PC, 3D PC and contrast-enhanced 3D TOF sequences. The statistical analysis was performed with the qui-square test. Four patients had follow-up exams and three patients underwent digital subtraction angiography. Results: main predisposing factors were: infection, use of oral contraceptives, hormone replacement therapy and collagenosis. Predominant symptoms included: focal deficit, headache, alteration of consciousness level and seizures. Most frequent parenchymal manifestations were: cortical/subcortical edema or infarct, venous congestion and collateral circulation, meningeal enhancement and thalamic and basal ganglia edema or infarct. Occlusion occurred mainly in superior sagittal, left transverse, left sigmoid and straight sinuses. Cavernous sinus and cortical veins thrombosis are uncommon events. Conclusion: cerebral venous thrombosis is an uncommon cause of stroke, with favorable prognosis because of its reversibility. Diagnosis is highly dependent on the radiologist capacity to recognize the presentations of this disease, principally in cases where the diagnosis is suggested by parenchymal abnormalities rather than necessarily by visualization of the thrombus itself. An accurate and rapid diagnosis allows an immediate treatment, reducing the morbidity and mortality rates. (author)

Early Experience with the Amplatzer Vascular Plug II for Occlusive Purposes in Arteriovenous Hemodialysis Access

International Nuclear Information System (INIS)

Powell, Steven; Narlawar, Ranjeet; Odetoyinbo, Tolulola; Littler, Peter; Oweis, Deyana; Sharma, Ajay; Bakran, Ali

2010-01-01

The Amplatzer Vascular Plug Type II (AVP II) has proven effective in the therapeutic embolization of various vascular lesions. It benefits from very rapid occlusion of the target lesion and can be deployed, retrieved, and redeployed if required. There is no literature available on use of the AVP II in the maintenance, closure, and management of complicated arteriovenous access in hemodialysis patients. In this series, we present our clinical experience with the use of the AVP II for embolization of problematic hemodialysis access. The AVP II is a self-expandable Nitinol wire-mesh device. Mounted on a delivery wire it has the capability to be deployed, recaptured, and redeployed. In total seven patients (four males: one diabetic, all nonsmokers), with ages ranging from 44 to 81 years (mean, 63 years), were treated between July 2008 and January 2009. One patient had not started dialysis. The remaining six patients had varied histories, with the time on hemodialysis ranging from 1 to 21 years. Retrospective review of clinical notes revealed patient demographics, type of access, device size, deployment site, and outcomes. Indications for embolization included steal syndrome (one patient), high-flow tributaries (two patients), and limb swelling (four patients). All patients had clinical and sonographical follow-up to 3 months. Surgical ligation had either failed, was considered a contraindication due to concerns regarding wound healing, or was considered difficult due to complex venous anatomy. Only one device was used in each patient, ranging from 6 to 16 mm in diameter. Immediate technical success was seen in 100%. All these patients were followed up clinically in the vascular access radiology clinic at 4 weeks and 3 months. Occlusion of the treated vessel and resolution of symptoms were reconfirmed in 100% of cases at 3 months. It was also noted whether patients were having successful dialysis, if required. There were no complications. Average procedural time was 19

Preferred retinal location induced by macular occlusion in a target recognition task

Science.gov (United States)

Ness, James W.; Zwick, Harry; Molchany, Jerome W.

1996-04-01

Laser-induced central retinal damage not only may diminish visual function, but also may diminish afferent input that provides the ocular motor system with the feedback necessary to move the target to the fovea. Local visual field stabilizations have been used to demonstrate that central artificial occlusions in the normal retina suppress visual function. The purpose of this paper is to evaluate the effect of local field stabilizations on the ocular motor system in a contrast sensitivity task. Five subjects who tested normal in a standard clinical eye exam viewed landolt rings at varying visual angles under three artificial scotoma conditions and a no scotoma condition. The scotoma conditions were a 2 degree(s) and 5 degree(s) stabilized central scotoma and a 2 degree(s) stabilized scotoma positioned 1 degree(s) nasal to the fovea. A Dual Purkinje Eye-Tracker (SRI, version 5) was used to provide eye-position data and to stabilize the artificial scotoma on the retina. The data showed a consistent preference for placing the target in the superior retina under the 2 degree(s) and 5 degree(s) conditions with a strong positive correlation between visual angle and deflection of the eye position into the superior retina. These data suggest that loss of visual function from laser-induced foveal damage may be due in part to a disruption in the ocular motor system. Thus, even if some function remains in the damage site ophthalmoscopically, the ocular motor system may organize around a nonfoveal retinal location, behaviorally suppressing foveal input.

Occlusal risk factors associated with temporomandibular disorders in young adults with normal occlusions.

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Wang, Chen; Yin, Xinmin

2012-10-01

The aim of this study was to characterize occlusal stability in young adults with temporomandibular disorder (TMD). Thirty-one patients (aged 19-31 years) with complete natural dentition and Angle class I occlusion who exhibited TMD were compared with 31 age- and sex-matched healthy control subjects. The occlusal registrations were performed using the T-Scan II occlusal imaging and analysis system. Center of occlusal force, asymmetry index of occlusal force, maximal movement of COF, premature contacts, clusion time, and disclusion time were recorded. Compared with control subjects, TMD subjects had a significantly higher frequency of premature contacts (16/32, 50.0%) and greater bilateral asymmetry in the occlusal force. Furthermore, prolonged clusion time and disclusion time also were observed in TMD subjects. These results suggest that a significant association exists between occlusal stability and TMD in young adults. Copyright © 2012 Elsevier Inc. All rights reserved.

Venous hemodynamic changes in lower limb venous disease

DEFF Research Database (Denmark)

Lee, Byung Boong; Nicolaides, Andrew N; Myers, Kenneth

2016-01-01

). Their aim was to confirm or dispel long-held hemodynamic principles and to provide a comprehensive review of venous hemodynamic concepts underlying the pathophysiology of lower limb venous disorders, their usefulness for investigating patients and the relevant hemodynamic changes associated with various...... forms of treatment. Chapter 1 is devoted to basic hemodynamic concepts and normal venous physiology. Chapter 2 presents the mechanism and magnitude of hemodynamic changes in acute deep vein thrombosis indicating their pathophysiological and clinical significance. Chapter 3 describes the hemodynamic...... changes that occur in different classes of chronic venous disease and their relation to the anatomic extent of disease in the macrocirculation and microcirculation. The next four chapters (Chapters 4-7) describe the hemodynamic changes resulting from treatment by compression using different materials...

Constriction of collateral arteries induced by "head-up tilt" in patients with occlusive arterial disease of the legs

DEFF Research Database (Denmark)

Agerskov, K; Henriksen, O; Tønnesen, K H

1981-01-01

The effect of head-up tilt on leg blood flow and segmental arterial blood pressures was studied in 21 patients with occlusion or severe stenosis of the common or superficial femoral artery. Arterial pressure was measured directly in the brachial artery, common femoral artery and popliteal artery....... Relative change in blood flow in the leg during tilt was estimated by changes in arterio-venous oxygen differences and by the indicator dilution technique in nine patients. Head-up tilt caused a decrease in leg blood flow of 36% corresponding to an increase in total vascular resistance of 57%. Tilt did...... not change the pressure gradient from femoral to popliteal artery in the patients with occlusion of the superficial femoral artery, indicating that the flow resistance offered by the collateral arteries had increased. In a bilateral sympathectomised patient the increase in collateral resistance was almost...

Thromboembolic Risk of Endovascular Intervention for Lower Extremity Deep Venous Thrombosis.

Science.gov (United States)

Lindsey, Philip; Echeverria, Angela; Poi, Mun J; Matos, Jesus; Bechara, Carlos F; Cheung, Mathew; Lin, Peter H

2018-05-01

This study evaluated the risk of thromboembolism during endovascular interventions in patients with symptomatic lower extremity deep vein thrombosis (DVT) METHODS: Clinical records of all patients who underwent endovascular interventions for symptomatic lower extremity DVT from 2001 to 2017 were retrospectively analyzed using a prospectively maintained database. Only patients who received an inferior vena cava (IVC) filter were included in the analysis. Trapped intrafilter thrombus was assessed for procedure-related thromboembolism. Clinical outcomes of thrombus management and thromboembolism risk were analyzed. A total 172 patients (mean age 57.4 years, 98 females) who underwent 174 endovascular DVT interventions were included in the analysis. Treatment strategies included thrombolytic therapy (64%), mechanical thrombectomy (n = 86%), pharmacomechanical thrombolysis (51%), balloon angioplasty (98%), and stent placement (28%). Thrombectomy device used included AngioJet (56%), Trellis (19%), and Aspire (11%). Trapped IVC filter thrombus was identified in 58 patients (38%) based on the IVC venogram. No patient developed clinically evident pulmonary embolism (PE). IVC filter retrieval was performed in 98 patients (56%, mean 11.8 months after implantation). Multivariate analysis showed that iliac vein occlusion (P = 0.04) was predictive for procedure-related thromboembolism. Iliac vein thrombotic occlusion is associated with an increased thromboembolic risk in DVT intervention. Retrievable IVC filter should be considered when performing percutaneous thrombectomy in patients with iliac venous occlusion to prevent PE. Copyright © 2017 Elsevier Inc. All rights reserved.

Microfluidics for investigating vaso-occlusions in sickle cell disease.

Science.gov (United States)

Horton, Renita E

2017-07-01

SCD stems from amutation in the beta globin gene. Upon deoxygenation, hemoglobin polymerizes and triggers RBC remodeling. This phenomenon is central to SCD pathogenesis as individuals suffering from the disease are plagued by painful vaso-occlusive crises episodes. These episodes are the result of a combination of processes including inflammation, thrombosis, and blood cell adhesion to the vascular wall which leads to blockages within the vasculature termed vaso-occlusions. Vaso-occlusive episodes deprive tissues of oxygen and are a major contributor to SCD-related complications; unfortunately, the complex mechanisms that contribute to vaso-occlusions are not well understood. Vaso-occlusions can occur in post-capillary venules; hence, the microvasculature is a prime target for SCD therapies. Traditional in vitro systems poorly recapitulate architectural and dynamic flow properties of in vivo systems. However, microfluidic devices can capture features of the native vasculature such as cellular composition, flow, geometry, and ECM presentation. This review, although not comprehensive, highlights microfluidic approaches that aim to improve our current understanding of the pathophysiological mechanisms surrounding SCD. Microfluidic platforms can aid in identifying factors that may contribute to disease severity and can serve as suitable test beds for novel treatment strategies which may improve patient outcomes. © 2017 John Wiley & Sons Ltd.

Hypoattenuation on CTA images with large vessel occlusion: timing affects conspicuity

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Dave, Prasham [University of Ottawa, MD Program, Faculty of Medicine, Ottawa, ON (Canada); Lum, Cheemun; Thornhill, Rebecca; Chakraborty, Santanu [University of Ottawa, Department of Radiology, Ottawa, ON (Canada); Ottawa Hospital Research Institute, Ottawa, ON (Canada); Dowlatshahi, Dar [Ottawa Hospital Research Institute, Ottawa, ON (Canada); University of Ottawa, Division of Neurology, Department of Medicine, Ottawa, ON (Canada)

2017-05-15

Parenchymal hypoattenuation distal to occlusions on CTA source images (CTASI) is perceived because of the differences in tissue contrast compared to normally perfused tissue. This difference in conspicuity can be measured objectively. We evaluated the effect of contrast timing on the conspicuity of ischemic areas. We collected consecutive patients, retrospectively, between 2012 and 2014 with large vessel occlusions that had dynamic multiphase CT angiography (CTA) and CT perfusion (CTP). We identified areas of low cerebral blood volume on CTP maps and drew the region of interest (ROI) on the corresponding CTASI. A second ROI was placed in an area of normally perfused tissue. We evaluated conspicuity by comparing the absolute and relative change in attenuation between ischemic and normally perfused tissue over seven time points. The median absolute and relative conspicuity was greatest at the peak arterial (8.6 HU (IQR 5.1-13.9); 1.15 (1.09-1.26)), notch (9.4 HU (5.8-14.9); 1.17 (1.10-1.27)), and peak venous phases (7.0 HU (3.1-12.7); 1.13 (1.05-1.23)) compared to other portions of the time-attenuation curve (TAC). There was a significant effect of phase on the TAC for the conspicuity of ischemic vs normally perfused areas (P < 0.00001). The conspicuity of ischemic areas distal to a large artery occlusion in acute stroke is dependent on the phase of contrast arrival with dynamic CTASI and is objectively greatest in the mid-phase of the TAC. (orig.)

Direct venous thrombolysis and venous angioplasty in the upper extremity

International Nuclear Information System (INIS)

Hollmann, J.P.; Guenther, R.W.

1987-01-01

Venous thromboses of stenoses in the upper extremity are often the result of a compression syndrome of the shoulder girdle, the Paget-von Schroetter syndrome, vascular surgery, space-occupying lesions in the mediastinum or the result of catheterisation. Direct venous thrombolysis and venous angioplasty were performed successfully in six patients. (orig.) [de

Analysis of the vertebral venous system in relation to cerebral venous drainage on MR angiography

International Nuclear Information System (INIS)

Baik, Seung Kug; Sohn, Chul Ho; Kim, Gab Chul; Kim, Yong Sun

2004-01-01

In the supine position, cerebral venous drainage occurs primarily through the internal jugular veins, as seen on venous phase cerebral angiography. However, in the erect position, the vertebral venous system represents the major alternative pathway of cerebral venous drainage, while outflow through the internal jugular veins is absent or negligible. The purpose of this study is to evaluate the vertebral venous system and its relationship between the surrounding venous structures using magnetic resonance angiography (MRA) in the case of subjects in the supine position. We retrospectively reviewed the results of 65 patients (M:F = 31: 34, mean age 61.6 years) who underwent multi-phase contrast-enhanced carotid MRA. The imaging studies were performed using a 3.0 T MR unit (TR: 5.2, TE: 1.1, FA: 20, 3.8 thickness, EC: 1). We analyzed the appearance and extent of the vertebral venous system (vertebral venous plexus and vertebral artery venous plexus) and the internal jugular vein on the venous phase images. We also evaluated the main drainage pattern of the cerebral venous drainage and the drainage pattern of the vertebral venous system. The visualized vertebral venous system was defined as either poor, vertebral venous plexus dominant, vertebral artery venous plexus dominant or mixed. In the vertebral venous system, the vertebral artery venous plexus was visualized in 54 cases (83%). The appearance of the visualized vertebral artery venous plexus was symmetrical in 39 cases (72%) and asymmetrical in 15 cases (28%). The extent of the visualized vertebral artery venous plexus was partial in 26 cases (48%) and complete in 28 cases (52%). The vertebral venous plexus was visualized in 62 cases (95%). The appearance of the visualized vertebral artery venous plexus was symmetrical in 43 cases (69%) and asymmetrical in 19 cases (31%). The extent of the visualized vertebral artery venous plexus was partial in 35 cases (56%) and complete in 27 cases (44%). The appearance of the

Evaluation of great saphenous vein occlusion rate and clinical outcome in patients undergoing laser thermal ablation with a 1470-nm bare fiber laser with low linear endovenous energy density

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Walter Junior Boim Araujo

2015-12-01

Full Text Available Abstract Background Water-specific 1470-nm lasers enable vein ablation at lower energy densities and with fewer side effects because they target interstitial water in the vessel wall. Objectives To determine great saphenous vein (GSV occlusion rate after thermal ablation with 1470-nm laser using 7W power and to evaluate clinical outcomes and complications. Method Nineteen patients (31 GSVs underwent thermal ablation. Follow-up duplex scanning, clinical evaluation using the Venous Clinical Severity Score (VCSS, and evaluation of procedure-related complications were performed at 3-5 days after the procedure and at 30 and 180 days. Results Mean patient age was 46 years and 17 of the patients were female (89.47%. Of 31 limbs treated, 2 limbs were clinical class C2, 19 were C3, 9 were C4, and 1 limb was C5 according to the Clinical-Etiology-Anatomy-Pathophysiology (CEAP classification. Mean linear endovenous energy density was 33.53 J/cm. The GSV occlusion rate was 93.5% immediately after treatment, 100% at 3-5 days and 100% at 30 days after treatment and 87.1% 180 days after treatment. There was a significant reduction in VCSS at all time points. Conclusions The data from this study support the possibility that the incidence of complications can be reduced without significantly affecting the clinical outcomes, by using lower energy density. However, this appears to be at the cost of reduced efficacy in terms of GSV occlusion rates.

Optimization of the static occlusion by "occlusal surface settling" in the Cerec 3D software.

Science.gov (United States)

Späth, C; Kordass, B

2006-04-01

The adjustment of the static occlusion can be automated in computer-based systems. The Cerec 3D software makes it possible to take preformed occlusal surfaces from a database and adapt them to the antagonist. In this adaptation (settling), the CAD occlusal surface "settles" as whole or each cusp individually into the occlusal surface of the antagonist until stable occlusion is reached. Two occlusal surface shapes were compared: Vita Physiodens and Lee Culp. An index was formed from the number, quality, and position of the occlusal contacts for 35 model cases (25 molars, 10 premolars). With regard to the settling of the total occlusal surfaces, there were no differences between the two occlusal surface shapes. In "cusp settling" of the molars, Vita Physiodens performed significantly better. In the comparison of the 1st with the 3rd settling process, significant improvements occurred the 3rd time in many cases when settling individual cusps, but in clearly fewer cases in the settling process of the total occlusal surface. The Lee Culp tooth occlusion improved especially after the 3rd settling process of individual cusps. It is therefore expedient to combine both settling versions with one another.

The use of indium-111 labeled platelet scanning for the detection of asymptomatic deep venous thrombosis in a high risk population

International Nuclear Information System (INIS)

Siegel, R.S.; Rae, J.L.; Ryan, N.L.; Edwards, C.; Fortune, W.P.; Lewis, R.J.; Reba, R.C.

1989-01-01

Five hundred indium-111 labeled platelet imaging studies (387 donor and 113 autologous) were performed postoperatively in 473 patients who had undergone total hip replacement, total knee replacement, or internal fixation of a hip fracture to detect occult deep venous thrombosis. All patients had been anticoagulated prophylactically with aspirin, warfarin sodium (Coumadin), or dextran. Thirty-four possible cases of proximal deep venous thrombosis were identified in 28 asymptomatic patients. To verify the scan results, 31 venograms were performed in 25 patients (three refused). In 21 of 31 cases, totally occlusive thrombi were detected; in 5 cases, partially occlusive thrombi were detected; in 5 cases, no thrombus was seen. No patient who had a negative scan nor any patient who had a verified positive scan (and received appropriate heparin therapy) subsequently developed symptoms or signs of pulmonary embolism. One hundred forty-one indium study patients also underwent Doppler ultrasonography/impedance plethysmography (Doppler/IPG) as a comparative non-invasive technique. In 137 cases, the results of the indium study and Doppler/IPG studies were congruent. The indium study had no false negative results that were detected by Doppler/IPG. No patient had any clinically evident toxicity. These results suggest that indium-111 labeled platelet scanning is a safe, noninvasive means for identifying DVT in high risk patients

Endobronchial Occlusion Stent: A Preliminary Experimental Study

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Choi, Yo Won; Jeong, Woo Kyoung; Lee, Seoung Hoon; Heo, Jeong Nam; Jeon, Seok Chol [Hanyang University College of Medicine, Seoul (Korea, Republic of); Ko, Gi Young; Song, Ho Young [University of Ulsan College of Medicine, Ulsan (Korea, Republic of)

2010-04-15

To evaluate the safety and the technical feasibility of the use of an endobronchial occlusion stent and to get preliminary data for the development of the optimal material required for endobronchial occlusions. A commercialized, self-expandable tracheobronchial stent was modified; one half had a polyurethane cover with an occluded end and the other half was uncovered with a flaring configuration. The occluded end was placed such that it would face the distal lung. Under fluoroscopic guidance, seven stents were placed at the lower lobar bronchus in 6 mini-pigs. The bronchial obstruction was examined immediately after stent placement. Chest radiographs were taken at days 1, 7, 14, and 28 after stent placement and the removed airways from two, two, one, and one mini-pigs sacrificed on corresponding days were examined for the maintenance of bronchial obstruction. Stents were successfully placed and induced the immediate bronchial obstruction in all mini-pigs. Five of seven airways with occlusion stents maintained an obstruction until the mini-pigs were sacrificed. Proximal stent migration occurred in two mini-pigs (29%), and pulmonary consolidations were observed distal to four of the stents (57%). The placement of an endobronchial occlusion stent and the obstruction of targeted bronchi seem to be feasible, but an add-on check valve should be considered to prevent stent migration and obstructive pneumonia

Retinal oximetry during treatment of retinal vein occlusion by ranibizumab in patients with high blood pressure and dyslipidemia.

Science.gov (United States)

Keilani, C; Halalchi, A; Wakpi Djeugue, D; Regis, A; Abada, S

2016-12-01

In the present study, we examined retinal vascular oxygen saturation in patients with retinal vein occlusion (RVO), high blood pressure (HBP) and dyslipidemia, before and during intravitreal vascular endothelial growth factor (VEGF) injection (ranibizumab). We retrospectively reviewed the medical records of six patients with visual acuity (VA) reduced by macular edema (ME) secondary to RVO with HBP and dyslipidemia, who underwent intravitreal anti-VEGF injection between October 2014 and February 2015 in the department of ophthalmology of François-Quesnay Hospital at Mantes-la-Jolie (France). The main inclusion criterion was the presence of RVO with ME and decreased VA. The primary endpoint was improvement of retinal venous oxygen saturation in patients with RVO before and 3 months after intravitreal ranibizumab injection. Secondary outcomes were improvement of retinal arterial oxygen saturation, improvement of best-corrected visual acuity (BCVA) on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, regression of ME measured by the central macular thickness (CMT) in nm and studying the correlation between blood pressure (BP) and retinal venous oxygen saturation before and after ranibizumab. Six eyes of six patients were included. Before treatment, the mean (standard deviation [SD]) of the retinal venous saturation (%) was 38.1±14.2. Three months after the injections, the mean (SD) of the retinal venous saturation (%) increased statistically significantly 49.2±11 (P=0.03). In this study, retinal venous oxygen saturation in patients with RVO, HBP and dyslipidemia was partially normalized during intravitreal ranibizumab treatment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Analysis of decrease in lung perfusion blood volume with occlusive and non-occlusive pulmonary embolisms

International Nuclear Information System (INIS)

Ikeda, Yohei; Yoshimura, Norihiko; Hori, Yoshiro; Horii, Yosuke; Ishikawa, Hiroyuki; Yamazaki, Motohiko; Noto, Yoshiyuki; Aoyama, Hidefumi

2014-01-01

Highlights: • The proportion of preserved PE lesions in the non-occlusive group was 76.7% (33/43). • HUs of the iodine map were significantly higher in the non-occlusive group than in the occlusive group. • There was no significant difference in HUs between the non-occlusive and corresponding normal group. - Abstract: Purpose: The aim of this study was to determine if lung perfusion blood volume (lung PBV) with non-occlusive pulmonary embolism (PE) differs quantitatively and visually from that with occlusive PE and to investigate if lung PBV with non-occlusive PE remains the same as that without PE. Materials and methods: Totally, 108 patients suspected of having acute PE underwent pulmonary dual-energy computed tomography angiography (DECTA) between April 2011 and January 2012. Presence of PE on DECTA was evaluated by one radiologist. Two radiologists visually evaluated the PE distribution (segmental or subsegmental) and its nature (occlusive or non-occlusive) on DECTA and classified perfusion in lung PBV as “decreased,” “slightly decreased,” and “preserved”. Two radiologists used a lung PBV application to set a region of interest (ROI) in the center of the lesion and measured HU values of an iodine map. In the same slice as the ROI of the lesion and close to the lesion, another ROI was set in the normal perfusion area without PE, and HUs were measured. The proportion of lesions was compared between the occlusive and non-occlusive groups. HUs were compared among the occlusive, non-occlusive, and corresponding normal groups. Results: Twenty-five patients had 80 segmental or subsegmental lesions. There were 37 and 43 lesions in the occlusive and non-occlusive groups, respectively. The proportion of decreased lesions was 73.0% (27/37) in the occlusive group, while that of preserved lesions in the non-occlusive group was 76.7% (33/43). There was a significant difference in the proportion of lesions (P < 0.001) between the two groups. HUs of the

Venous digital subtraction angiography of the renal arteries in hypertensive patients

International Nuclear Information System (INIS)

Brecht, G.; Harder, T.; Franken, T.

1984-01-01

We carried out 1890 venous digital subtraction angiograms; this included 113 patients with hypertension in order to exclude renal artery stenosis. On four occasions it was used following surgery on a renal artery. Renal artery stenosis or occlusion was demonstrated in twelve patients, and other vascular diseases or anomalies were found in 24. Two abnormal renal arteries were found following renal artery surgery. The results are compared with smaller groups of patients examined by DSA, and with the results of conventional subtraction methods reported in the literature. In only eight patients (6.8%) DSA provided insufficient information and had to be supplemented by aortography. The method has proved to be a valuable and simple screening method for the investigation of hypertension. (orig.) [de

Varicose Veins: Role of Mechanotransduction of Venous Hypertension

Science.gov (United States)

Atta, Hussein M.

2012-01-01

Varicose veins affect approximately one-third of the adult population and result in significant psychological, physical, and financial burden. Nevertheless, the molecular pathogenesis of varicose vein formation remains unidentified. Venous hypertension exerted on veins of the lower extremity is considered the principal factor in varicose vein formation. The role of mechanotransduction of the high venous pressure in the pathogenesis of varicose vein formation has not been adequately investigated despite a good progress in understanding the mechanomolecular mechanisms involved in transduction of high blood pressure in the arterial wall. Understanding the nature of the mechanical forces, the mechanosensors and mechanotransducers in the vein wall, and the downstream signaling pathways will provide new molecular targets for the prevention and treatment of varicose veins. This paper summarized the current understanding of mechano-molecular pathways involved in transduction of hemodynamic forces induced by blood pressure and tries to relate this information to setting of venous hypertension in varicose veins. PMID:22489273

Effect of occlusion amblyopia after prescribed full-time occlusion on long-term visual acuity outcomes.

Science.gov (United States)

Longmuir, Susannah; Pfeifer, Wanda; Scott, William; Olson, Richard

2013-01-01

To investigate the incidence and characteristics of occlusion amblyopia with prescribed full-time patching and determine its effect on long-term visual acuity outcomes. The records of patients younger than 10 years diagnosed as having amblyopia between 1970 and 2000 were retrospectively reviewed. Patients were prescribed full-time occlusion and observed until completion of therapy. Of 597 patients treated for amblyopia by full-time patching, 115 were diagnosed as having occlusion amblyopia (19.3%). Seventy-five percent (86 of 115) developed occlusion amblyopia during the first episode of full-time patching. Occlusion amblyopia occurred more frequently in children prescribed full-time patching at an earlier age (P = .0002), with an odds ratio of 8.56 (95% confidence interval: 2.73, 26.84) in children younger than 36 months and 2.66 (95% confidence interval: 0.96, 7.37) in children between 36 and 59 months old. Seven of the patients with occlusion amblyopia did not reverse fixation and continued to fixate with the initially amblyopic eye after treatment. Final visual acuity in these eyes with occlusion amblyopia was 20/30 or better. After cessation of treatment, the final interocular difference in visual acuity was less in patients with a history of occlusion amblyopia (P = .003). Occlusion amblyopia occurred at all ages, but the incidence decreased with increasing age. Patients who developed occlusion amblyopia with prescribed full-time occlusion had less interocular visual acuity difference than patients who did not, suggesting that development of occlusion amblyopia can indicate the potential for the development of better vision in the originally amblyopic eye. Copyright 2013, SLACK Incorporated.

The lingualized occlusion of complete denture

Institute of Scientific and Technical Information of China (English)

BEN Wei-hong; Eleni Roumanas

2008-01-01

This article reviews the literatures dealing with the lingualized occlusion of complete denture including the origin,development and research. Lingualized occlusion is a valuable concept because many advantages of anatomic and nonanatomic occlusions are retained,satisfactory occlusion is easily obtained,balanced occlusion can be accomplished.

Rivaroxaban attenuates thrombosis by targeting the NF-κB signaling pathway in a rat model of deep venous thrombus

OpenAIRE

Ma, Junhao; Li, Xinxi; Wang, Yang; Yang, Zhenwei; Luo, Jun

2017-01-01

Anticoagulant therapy is commonly used for the prevention and treatment of patients with deep venous thrombus. Evidence has shown that rivaroxaban is a potential oral anticoagulant drug for the acute treatment of venous thromboembolism. However, the rivaroxaban-mediated molecular mechanism involved in the progression of deep venous thrombosis has not been investigated. In the present study, we investigated the efficacy of rivaroxaban and the underlying signaling pathways in the prevention and...

Incidence of upper limb venous thrombosis associated with peripherally inserted central catheters (PICC).

Science.gov (United States)

Abdullah, B J J; Mohammad, N; Sangkar, J V; Abd Aziz, Y F; Gan, G G; Goh, K Y; Benedict, I

2005-07-01

The objective of this study was to prospectively determine the incidence of venous thrombosis (VT) in the upper limbs in patients with peripherally inserted central catheters (PICC). We prospectively investigated the incidence of VT in the upper limbs of 26 patients who had PICC inserted. The inclusion criteria were all patients who had a PICC inserted, whilst the exclusion criterion was the inability to perform a venogram (allergies, previous contrast medium reaction and inability of gaining venous access). Both valved and non-valved catheters were evaluated. Prior to removal of the PICC, an upper limb venogram was performed. The number of segments involved with VT were determined. The duration of central venous catheterization was classified as; less than 6 days, between 6 days and 14 days and more than 14 days. VT was confirmed in 38.5% (10/26) of the patients. The majority 85.7% (12/14) were complete occlusive thrombi and the majority of VT only involved one segment. There was no statistical correlation between the site of insertion of the PICC and the location of VT. Neither was there any observed correlation between the occurrence of VT with the patient's history of hypertension, hypercholesterolaemia, coronary artery disease, diabetes mellitus, cardiac insufficiency, smoking or cancer. There was also no statistical correlation with the size of the catheter. In conclusion, PICCs are associated with a significant risk of upper extremity deep vein thrombosis (UEVT).

Percutaneous subclavian artery stent-graft placement following failed ultrasound guided subclavian venous access

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Szkup Peter

2006-05-01

Full Text Available Abstract Background Ultrasound guidance for central and peripheral venous access has been proven to improve success rates and reduce complications of venous cannulation. Appropriately trained and experienced operators add significantly to diminished patient morbidity related to venous access procedures. We discuss a patient who required an arterial stent-graft to prevent arterial hemorrhage following inadvertent cannulation of the proximal, ventral, right subclavian artery related to unsuccessful ultrasound guided access of the subclavian vein. Case presentation During pre-operative preparation for aortic valve replacement and aorto-coronary bypass surgery an anesthetist attempted ultrasound guided venous access. The ultrasound guided attempt to access the right jugular vein failed and the ultrasound guided attempt at accessing the subclavian vein resulted in inappropriate placement of an 8.5 F sheath in the arterial system. Following angiographic imaging and specialist consultations, an arterial stent-graft was deployed in the right subclavian artery rather than perform an extensive anterior chest wall resection and dissection to extract the arterial sheath. The patient tolerated the procedure, without complication, despite occlusion of the right internal mammary artery and the right vertebral artery. There were no neurologic sequelae. There was no evidence of hemorrhage after subclavian artery sheath extraction and stent-graft implantation. Conclusion The attempted ultrasound guided puncture of the subclavian vein resulted in placement of an 8.5 F subclavian artery catheter. Entry of the catheter into the proximal subclavian artery beneath the medial clavicle, the medial first rib and the manubrium suggests that the operator, most likely, did not directly visualize the puncture needle enter the vessel with the ultrasound. The bones of the anterior chest impede the ultrasound beam and the vessels in this area would not be visible to ultrasound

Venous Ulcers

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Caprini, J.A.; Partsch, H.; Simman, R.

2013-01-01

Venous leg ulcers are the most frequent form of wounds seen in patients. This article presents an overview on some practical aspects concerning diagnosis, differential diagnosis and treatment. Duplex ultrasound investigations are essential to ascertain the diagnosis of the underlying venous pathology and to treat venous refluxes. Differential diagnosis includes mainly other vascular lesions (arterial, microcirculatory causes), hematologic and metabolic diseases, trauma, infection, malignancies. Patients with superficial venous incompetence may benefit from endovenous or surgical reflux abolition diagnosed by Duplex ultrasound. The most important basic component of the management is compression therapy, for which we prefer materials with low elasticity applied with high initial pressure (short-stretch bandages and Velcro-strap devices). Local treatment should be simple, absorbing and not sticky dressings keeping adequate moisture balance after debridement of necrotic tissue and biofilms are preferred. After the ulcer is healed compression therapy should be continued in order to prevent recurrence. PMID:26236636

Full-Thickness Retinochoroidal Incision in the Management of Central Retinal Vein Occlusion

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San-Ni Chen

2015-01-01

Full Text Available Purpose. To evaluate the clinical outcomes in patients with central retinal vein occlusion (CRVO treated with full-thickness retinochoroidal incisions and to compare whether there is difference in treatment response in ischemic and nonischemic CRVO. Methods. Retrospective study of patients of CRVO receiving full-thickness retinochoroidal incisions in Changhua Christian Hospital. Fluorescein angiography (FA, slit-lamp biomicroscopy, indirect funduscopy, best corrected visual acuity, and central macular thickness (CMT measured by optical coherence tomography were performed pre- and postoperatively. Patients were divided into an ischemic and nonischemic group according to the findings of FA. Patients were followed up for at least 1 year. Results. Twenty-eight eyes (14 ischemic and 14 nonischemic CRVO were included. Functional retinochoroidal venous anastomosis (RCVA was achieved in 48 of the 65 retinochoroidal incisions (73.8%. Central macular thickness (CMT and retinal hemorrhage decreased significantly after the surgery. Significant visual gain was observed postoperatively in the nonischemic group, but not in the ischemic group. Postoperative complications included vitreous hemorrhage (17.8%, neovascular glaucoma (7.1%, and preretinal fibrovasular membrane (10.7%, all of which were in the ischemic group. Conclusions. RCVA formation induced by retinochoroidal incisions could improve venous flow, and decrease CMT and retinal hemorrhage. However, only eyes with nonischemic CRVO showed visual improvement.

Occlusal stability in shortened dental arches.

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Witter, D J; Creugers, N H; Kreulen, C M; de Haan, A F

2001-02-01

Shortened dental arches consisting of anterior and premolar teeth have been shown to meet oral functional demands. However, the occlusal stability may be at risk as a result of tooth migration. The aim of this nine-year study was to investigate occlusal stability in shortened dental arches as a function over time. Occlusal stability indicators were: 'interdental spacing', 'occlusal contacts of anterior teeth in Intercuspal Position', 'overbite', 'occlusal tooth wear', and 'alveolar bone support'. Subjects with shortened dental arches (n = 74) were compared with subjects with complete dental arches (controls, n = 72). Repeated-measurement regression analyses were applied to assess age-dependent variables in the controls and to relate the occlusal changes to the period of time since the treatment that led to the shortened dental arches. Compared with complete dental arches, shortened dental arches had similar overbite and occlusal tooth wear. They showed more interdental spacing in the premolar regions, more anterior teeth in occlusal contact, and lower alveolar bone scores. Since the differences remained constant over time, we conclude that shortened dental arches can provide long-term occlusal stability. Occlusal changes were self-limiting, indicating a new occlusal equilibrium.

Evaluation of bone loss due to primary occlusal trauma in two experimental models of occlusal overload

OpenAIRE

LOPES, Ana Cristina Távora de Albuquerque; TÉO, Mirela Anne Quartaroli; CORRÊA, Mônica Grazieli; ISHIKIRIAMA, Bella Luna Colombini; CAMPOS, Mirella Lindoso Gomes

2016-01-01

Abstract Introduction Primary occlusal trauma (OT) is an injury of the periodontium with normal height as a result of occlusal forces which exceed their adaptive capacity. Objective To evaluate, histometrically, the alveolar bone loss in the furcation region of rats experimentally submitted to 2 models of occlusal overload. Material and method 45 animals randomly divided into 3 groups: Occlusal Interference (OI, n = 15) - fixing an orthodontic wire segment on the occlusal surface of the fi...

Medical management of venous ulcers.

Science.gov (United States)

Pascarella, Luigi; Shortell, Cynthia K

2015-03-01

Venous disease is the most common cause of chronic leg ulceration and represents an advanced clinical manifestation of venous insufficiency. Due to their frequency and chronicity, venous ulcers have a high socioeconomic impact, with treatment costs accounting for 1% of the health care budget in Western countries. The evaluation of patients with venous ulcers should include a thorough medical history for prior deep venous thrombosis, assessment for an hypercoagulable state, and a physical examination. Use of the CEAP (clinical, etiology, anatomy, pathophysiology) Classification System and the revised Venous Clinical Severity Scoring System is strongly recommended to characterize disease severity and assess response to treatment. This venous condition requires lifestyle modification, with affected individuals performing daily intervals of leg elevation to control edema; use of elastic compression garments; and moderate physical activity, such as walking wearing below-knee elastic stockings. Meticulous skin care, treatment of dermatitis, and prompt treatment of cellulitis are important aspects of medical management. The pharmacology of chronic venous insufficiency and venous ulcers include essentially two medications: pentoxifylline and phlebotropic agents. The micronized purified flavonoid fraction is an effective adjunct to compression therapy in patients with large, chronic ulceration. Copyright © 2015 Elsevier Inc. All rights reserved.

Diagnosis of venous disorders

International Nuclear Information System (INIS)

Minar, E.

1993-01-01

Limited accuracy in the clinic diagnosis of deep vein thrombosis (VT) makes such diagnostic tests such as duplex sonography or venography necessary. Exact information on the age and extent of the thrombus are necessary for the clinician to optimize the therapeutric management. The correct diagnosis of calf vein thrombosis and of recurrent VT in patients with postphlebitis changes also has implications for treatment. After exclusion of thrombosis, the radiologist should evaluate the leg for other possible causes of symptoms besides VT. Investigation of the venous sytem also has a role in the diagnosis in patients with suspected pulmonary embolism. In patients with chronic venous insuffficiency the deep venous system should assessed for patency and venous valve function. The superficial veins should be differentiated in segments with sufficient or insufficient venous valves, and it is also necessary to look for insufficiency of the perforrating veins. In patients with superficial phlebitis there is risk of propagation into the deep venous system. (orig.) [de

Cerebral venous angiomas

International Nuclear Information System (INIS)

Agnoli, A.L.; Hildebrandt, G.

1985-01-01

Clinical symptoms and radiological signs in 15 patients with cerebral venous malformations are presented and the diagnostic problems discussed. The circulation time in combination with cerebral malformations and angiomas of the scalp are described. CT findings in cases of venous malformations of the brain stem are evaluated. Spot-like enhancement, as well as sharply demarcated round shaped enhancement are characteristic for venous angiomas. Cavernous angiomas usually present as homogenous or inhomogenous round shaped enhanced areas. (Author)

Venous ulcers -- self-care

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... surgery to improve blood flow through your veins. Prevention If you are at risk for venous ulcers, take the steps listed above under Wound Care. ... weight if you are overweight. Manage your blood pressure and cholesterol levels. ... Venous leg ulcers - self-care; Venous insufficiency ulcers - self-care; Stasis ...

Vertebrobasilar Artery Occlusion

Directory of Open Access Journals (Sweden)

Schoen, Jessica

2011-05-01

Full Text Available The presentation of vertebrobasilar artery occlusion varies with the cause of occlusion and location of ischemia. This often results in delay in diagnosis. Areas of the brain supplied by the posterior circulation are difficult to visualize and usually require angiography or magnetic resonance imaging. Intravenous thrombolysis and local-intra arterial thrombolysis are the most common treatment approaches used. Recanalization of the occluded vessel significantly improves morbidity and mortality. Here we present a review of the literature and a case of a patient with altered mental status caused by vertebrobasilar artery occlusion. [West J Emerg Med. 2011;12(2:233-239.

Models of the venous system

DEFF Research Database (Denmark)

Mehlsen, J

2000-01-01

Cardiac output is largely controlled by venous return, the driving force of which is the energy remaining at the postcapillary venous site. This force is influenced by forces acting close to the right atrium, and internally or externally upon the veins along their course. Analogue models of the v......Cardiac output is largely controlled by venous return, the driving force of which is the energy remaining at the postcapillary venous site. This force is influenced by forces acting close to the right atrium, and internally or externally upon the veins along their course. Analogue models...... of the venous system require at least three elements: a resistor, a capacitor and an inductor, with the latter being of more importance in the venous than in the arterial system. Non-linearities must be considered in pressure/flow relations in the small venules, during venous collapse, or low flow conditions...

Use of a Puncture Needle for Recanalization of an Occluded Right Subclavian Vein

International Nuclear Information System (INIS)

Gupta, Himanshu; Murphy, Timothy P.; Soares, Gregory M.

1998-01-01

We report a patient in whom we used a puncture needle to initiate percutaneous recanalization of a chronic occlusion of the junction between the right subclavian vein and the right brachiocephalic vein. Under fluoroscopic guidance, an 18-gauge needle was used to puncture the right subclavian vein. When contrast material injected through the needle confirmed intravascular location, the needle was advanced until it deflected and perforated an occlusion balloon target positioned within the right brachiocephalic vein. This technique may be useful in patients with central venous occlusions that are refractory to traversal using traditional catheter and guidewire techniques

Venous, Arterialized-Venous, or Capillary Glucose Reference Measurements for the Accuracy Assessment of a Continuous Glucose Monitoring System.

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Kropff, Jort; van Steen, Sigrid C; deGraaff, Peter; Chan, Man W; van Amstel, Rombout B E; DeVries, J Hans

2017-11-01

Different reference methods are used for the accuracy assessment of continuous glucose monitoring (CGM) systems. The effect of using venous, arterialized-venous, or capillary reference measurements on CGM accuracy is unclear. We evaluated 21 individuals with type 1 diabetes using a capillary calibrated CGM system. Venous or arterialized-venous reference glucose samples were taken every 15 min at two separate visits and assessed per YSI 2300 STAT Plus. Arterialization was achieved by heated-hand technique. Capillary samples were collected hourly during the venous reference visit. The investigation sequence (venous or arterialized-venous) was randomized. Effectiveness of arterialization was measured by comparing free venous oxygen pressure (PO2) of both visit days. Primary endpoint was the median absolute relative difference (ARD). Median ARD using arterialized-venous reference samples was not different from venous samples (point estimated difference 0.52%, P = 0.181). When comparing the three reference methods, median ARD was also not different over the full glycemic range (venous 9.0% [n = 681], arterialized-venous 8.3% [n = 684], and capillary 8.1% [n = 205], P = 0.216), nor over the separate glucose ranges. Arterialization was successful (PO2 venous 5.4 kPa vs. arterialized-venous 8.9 kPa, P reference measurements did not significantly impact CGM accuracy. Venous reference seems preferable due to its ease of operation.

[Clinical analysis of patients with lower extremity deep venous thrombosis complicated with inferior vena cava thrombus].

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Dong, Dian-ning; Wu, Xue-jun; Zhang, Shi-yi; Zhong, Zhen-yue; Jin, Xing

2013-06-04

To explore the clinical profiles of patients with lower extremity deep venous thrombosis (DVT) complicated with inferior vena cava (IVC) thrombus and summarize their clinical diagnostic and therapeutic experiences. The clinical characteristics, diagnosis and treatment of 20 hospitalized patients with DVT complicated with inferior vena cava thrombus were analyzed retrospectively. All of them were of proximal DVT. There were phlegmasia cerulea dolens (n = 3), pulmonary embolism (n = 3) and completely occlusion of IVC (n = 5). Clinical manifestations were severe. Retrievable inferior vena cava filter (IVCF) was implanted for 17 cases. Catheter-directed thrombolysis (CDT) through ipsilateral popliteal vein was applied for 7 cases and systemic thrombolysis therapy for 8 cases. The effective rate of thrombolysis for fresh IVC thrombus was 100%. Among 5 cases with Cockett Syndrome, 3 cases underwent balloon dilatation angioplasty and endovascular stenting of iliac vein. And 17 IVCFs were retrieved successfully within 3 weeks. IVC thrombus disappeared completely in 15 cases. Systemic or local thrombolysis with protective IVCF is a safe and effective therapy for nonocclusive IVC thrombus in DVT. And CDT is recommended for symptomatic occlusive IVC thrombus.

Higher complication risk of totally implantable venous access port systems in patients with advanced cancer - a single institution retrospective analysis.

Science.gov (United States)

Chang, Yi-Fang; Lo, An-Chi; Tsai, Chung-Hsin; Lee, Pei-Yi; Sun, Shen; Chang, Te-Hsin; Chen, Chien-Chuan; Chang, Yuan-Shin; Chen, Jen-Ruei

2013-02-01

Totally implantable port systems are generally recommended for prolonged central venous access in diverse settings, but their risk of complications remains unclear for patients with advanced cancer. The aim of this study was to assess the risk of port system failure in patients with advanced cancer. We conducted a retrospective cohort study in a comprehensive cancer centre. A detailed chart review was conducted among 566 patients with 573 ports inserted during January-June, 2009 (average 345.3 catheter-days). Cox regression analysis was applied to evaluate factors during insertion and early maintenance that could lead to premature removal of the port systems due to infection or occlusion. Port system-related infection was significantly associated with receiving palliative care immediately after implantation (hazard ratio, HR = 7.3, 95% confidence interval, 95% CI = 1.2-46.0), after adjusting for probable confounders. Primary cancer site also impacted the occurrence of device-related infection. Receiving oncologic/palliative care (HR = 3.0, P = 0.064), advanced cancer stage (HR = 6.5, P = 0.077) and body surface area above 1.71 m(2) (HR = 3.4, P = 0.029) increased the risk of port system occlusion. Our study indicates that totally implantable port systems yield a higher risk of complications in terminally ill patients. Further investigation should be carefully conducted to compare outcomes of various central venous access devices in patients with advanced cancer and to develop preventive strategies against catheter failure.

A Review: Proteomics in Retinal Artery Occlusion, Retinal Vein Occlusion, Diabetic Retinopathy and Acquired Macular Disorders.

Science.gov (United States)

Cehofski, Lasse Jørgensen; Honoré, Bent; Vorum, Henrik

2017-04-28

Retinal artery occlusion (RAO), retinal vein occlusion (RVO), diabetic retinopathy (DR) and age-related macular degeneration (AMD) are frequent ocular diseases with potentially sight-threatening outcomes. In the present review we discuss major findings of proteomic studies of RAO, RVO, DR and AMD, including an overview of ocular proteome changes associated with anti-vascular endothelial growth factor (VEGF) treatments. Despite the severe outcomes of RAO, the proteome of the disease remains largely unstudied. There is also limited knowledge about the proteome of RVO, but proteomic studies suggest that RVO is associated with remodeling of the extracellular matrix and adhesion processes. Proteomic studies of DR have resulted in the identification of potential therapeutic targets such as carbonic anhydrase-I. Proliferative diabetic retinopathy is the most intensively studied stage of DR. Proteomic studies have established VEGF, pigment epithelium-derived factor (PEDF) and complement components as key factors associated with AMD. The aim of this review is to highlight the major milestones in proteomics in RAO, RVO, DR and AMD. Through large-scale protein analyses, proteomics is bringing new important insights into these complex pathological conditions.

Mesenteric vascular occlusion: a new diagnostic method using a radiolabeled monoclonal antibody reactive with platelets

International Nuclear Information System (INIS)

Oster, Z.H.; Som, P.; Zamora, P.O.

1989-01-01

A new method for diagnosing mesenteric vaso-occlusive bowel disease with the use of radioimmunoscintigraphy was developed and tested in experimental models of arterial and venous disease, as well as in a model simulating bowel strangulation. The method involves the use of a monoclonal antibody fragment mixture that binds to platelets. The antibody was labeled with technetium-99m, and imaging was performed with a gamma camera in the planar and single photon emission computed tomography modes. This method allowed visualization of areas of ischemia of 1-6 hours duration in bowel loops in 19 dogs 90-180 minutes after injection of the radiolabeled antibody. No bowel radioactivity accumulation occurred in dogs that underwent the same surgical procedure but were given a nonspecific Tc-99m-labeled antibody or in normal dogs given the specific antibody. It appears that the radiolabeled antibody used, which has higher reactivity with human platelets than with dog platelets, will be a good agent for noninvasive diagnosis of mesenteric vaso-occlusive disease in humans. It may also play a role in the intraoperative determination of the extent and location of ischemic bowel segments

Maximizing mandibular prosthesis stability utilizing linear occlusion, occlusal plane selection, and centric recording.

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Williamson, Richard A; Williamson, Anne E; Bowley, John; Toothaker, Randy

2004-03-01

The stability of mandibular complete dentures may be improved by reducing the transverse forces on the denture base through linear (noninterceptive) occlusion, selecting an occlusal plane that reduces horizontal vectors of force at occlusal contact, and utilizing a central bearing intraoral gothic arch tracing to record jaw relations. This article is intended to acquaint the reader with one technique for providing stable complete denture prostheses using the aforementioned materials, devices, and procedures.

Contralateral Occlusion Test: The effect of external ear canal occlusion on hearing thresholds.

Science.gov (United States)

Reis, Luis Roque; Fernandes, Paulo; Escada, Pedro

Bedside testing with tuning forks may decrease turnaround time and improve decision making for a quick qualitative assessment of hearing loss. The purpose of this study was to quantify the effects of ear canal occlusion on hearing, in order to decide which tuning fork frequency is more appropriate to use for quantifying hearing loss with the Contralateral Occlusion Test. Twenty normal-hearing adults (forty ears) underwent sound field pure tone audiometry with and without ear canal occlusion. Each ear was tested with the standard frequencies. The contralateral ear was suppressed with by masking. Ear occlusion was performed by two examiners. Participants aged between 21 and 30 years (25.6±3.03 years) showed an increase in hearing thresholds with increasing frequencies from 19.94dB (250Hz) to 39.25dB (2000Hz). The threshold difference between occluded and unoccluded conditions was statistically significant and increased from 10.69dB (250Hz) to 32.12dB (2000Hz). There were no statistically significant differences according to gender or between the examiners. The occlusion effect increased the hearing thresholds and became more evident with higher frequencies. The occlusion method as performed demonstrated reproducibility. In the Contralateral Occlusion Test, 256Hz or 512Hz tuning forks should be used for diagnosis of mild hearing loss, and a 2048Hz tuning fork should be used for moderate hearing loss. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Management of Cavoatrial Deep Venous Thrombosis: Incorporating New Strategies

Science.gov (United States)

Zayed, Mohamed A.; De Silva, Gayan S.; Ramaswamy, Raja S.; Sanchez, Luis A.

2017-01-01

Cavoatrial deep venous thrombosis (DVT) is diagnosed with increasing prevalence. It can be managed medically with anticoagulation or with directed interventions aimed to efficiently reduce the thrombus burden within the target venous segment. The type of management chosen depends greatly on the etiology and chronicity of the thrombosis, existing patient comorbidities, and the patient's tolerance to anticoagulants and thrombolytic agents. In addition to traditional percutaneous catheter-based pharmacomechanical thrombolysis, other catheter-based suction thrombectomy techniques have emerged in recent years. Each therapeutic modality requires operator expertise and a coordinated care paradigm to facilitate successful outcomes. Open surgical thrombectomy is alternatively reserved for specific patient conditions, including intolerance of anticoagulation, failed catheter-based interventions, or acute emergencies. PMID:28265127

Computerized occlusal analysis in bruxism

Directory of Open Access Journals (Sweden)

Lazić Vojkan

2006-01-01

Full Text Available Introduction. Sleep bruxism as nocturnal parafunction, also known as tooth grinding, is the most common parasomnia (sleep disorder. Most tooth grinding occurs during rapid eye movement - REM sleep. Sleep bruxism is an oral habit characterized by rhythmic activity of the masticatory muscles (m. masseter that causes forced contact between dental surfaces during sleep. Sleep bruxism has been associated with craniomandibular disorders including temporomandibular joint discomfort, pulpalgia, premature loss of teeth due to excessive attrition and mobility, headache, muscle ache, sleep interruption of an individual and problems with removable and fixed denture. Basically, two groups of etiological factors can be distinguished, viz., peripheral (occlusal factors and central (pathophysiological and psychological factors. The role of occlusion (occlusal discrepancies as the causative factor is not enough mentioned in relation to bruxism. Objective. The main objective of this paper was to evaluate the connection between occlusal factors and nocturnal parafunctional activities (occlusal disharmonies and bruxism. Method. Two groups were formed- experimental of 15 persons with signs and symptoms of nocturnal parafunctional activity of mandible (mean age 26.6 years and control of 42 persons with no signs and symptoms of bruxism (mean age 26.3 yrs.. The computerized occlusal analyses were performed using the T-Scan II system (Tekscan, Boston, USA. 2D occlusograms were analyzed showing the occlusal force, the center of the occlusal force with the trajectory and the number of antagonistic tooth contacts. Results. Statistically significant difference of force distribution was found between the left and the right side of the arch (L%-R% (t=2.773; p<0.02 in the group with bruxism. The difference of the centre of occlusal force - COF trajectory between the experimental and control group was not significant, but the trajectory of COF was longer in the group of

Prophylaxis of Venous Thrombosis.

Science.gov (United States)

Goldhaber, Samuel Z.

2001-06-01

Mechanical measures such as graduated compression stockings and intermittent compression boots are available for venous thrombosis prophylaxis, but compliance may be limited. Plantar venous pneumatic compression devices have attained widespread acceptance by both patients and nurses because of their comfort and compact size, but their track record for efficacy is poor. Inferior vena cava filters prevent pulmonary embolism, but do not halt the thrombotic process or prevent venous thrombosis. Pharmacologic prophylaxis traditionally has relied upon minidose unfractionated heparin; however, re-examination is warranted in the face of increasingly ill and complex patients. My opinion is that small, fixed doses of once-daily low molecular weight heparin will eventually replace minidose unfractionated heparin as the standard pharmacologic prophylaxis regimen for most surgical and medical patients. Prolongation of prophylaxis after hospital discharge should receive increased emphasis. Most patients being transferred to a skilled nursing facility should receive venous thromboembolism prophylaxis. Similarly, most patients undergoing total hip or knee replacement should receive prolonged preventive regimens, with at least 1 month of anticoagulation. Despite advances, certain aspects of venous thrombosis prophylaxis remain problematic. First, a surprisingly high number of hospitalized patients develop venous thrombosis because of failed (rather than omitted) prophylaxis. Second, many patients in intensive care have a combination of peripheral vascular disease and active bleeding (usually gastrointestinal) that precludes mechanical or pharmacologic prophylaxis. Third, neurosurgical patients undergoing craniotomy for brain tumors suffer a high rate of venous thrombosis and major pulmonary embolism despite the routine use of combined mechanical and pharmacologic prophylaxis. My opinion is that these three areas, in addition to the hospital culture of prophylaxis, should receive

Complete resolution of transplantation-associated thrombotic microangiopathy and hepatic veno-occlusive disease by defibrotide and plasma exchange.

Science.gov (United States)

Beşişik, Sevgi Kalayoğlu; Oztürk, Gülistan Bahat; Calişkan, Yaşar; Sargin, Deniz

2005-03-01

Transplantation-associated thrombotic microangiopathy has been associated with significantly reduced survival following allogeneic bone marrow transplantation. We describe here the course of Transplantation-associated thrombotic microangiopathy and hepatic veno-occlusive disease, and response to plasma exchange therapy. A 19-year-old male patient underwent hematopoietic stem cell transplantation (HSCT) from his HLA-matched brother for lymphoblastic lymphoma in the first complete remission. Transplantation-associated thrombotic microangiopathy was diagnosed 17 days after transplantation. At that time, neurological abnormalities were not present. Cyclosporin A (CsA) was discontinued. Hematological stabilization was recorded. On day +20, abdominal distention, painful hepatomegaly and ascites complicated the clinical picture. With a high hepatic venous pressure gradient (18mmH20), veno-occlusive disease of the liver was diagnosed and defibrotide was started, which resulted in a dramatic cessation of pain and increase in urinary output. However, transplantation-associated thrombotic microangiopathy-related symptoms progressed and plasma exchange was instituted, which resulted in worsening of veno-occlusive disease symptoms. He was referred to the Intensive Care Unit due to respiratory compromise and was intubated. Plasma exchange was continued in order after hemofiltration. In three days, fever resolved, hemofiltration could be stopped, and ventilator dependence ended. After 19 aphereses, serum LDH level returned to normal and schistocytes were minimal on microscopic examination of the blood film. Platelet count increase was more gradual. Plasma exchange was discontinued. On the 40th day of defibrotide, all symptoms related with veno-occlusive disease were resolved and defibrotide was stopped. We think that our case is important to establish the relation and management strategy of these two small vessel complications of HSCT.

[Effect of 2 methods of occlusion adjustment on occlusal balance and muscles of mastication in patient with implant restoration].

Science.gov (United States)

Wang, Rong; Xu, Xin

2015-12-01

To compare the effect of 2 methods of occlusion adjustment on occlusal balance and muscles of mastication in patients with dental implant restoration. Twenty patients, each with a single edentulous posterior dentition with no distal dentition were selected, and divided into 2 groups. Patients in group A underwent original occlusion adjustment method and patients in group B underwent occlusal plane reduction technique. Ankylos implants were implanted in the edentulous space in each patient and restored with fixed prosthodontics single unit crown. Occlusion was adjusted in each restoration accordingly. Electromyograms were conducted to determine the effect of adjustment methods on occlusion and muscles of mastication 3 months and 6 months after initial restoration and adjustment. Data was collected and measurements for balanced occlusal measuring standards were obtained, including central occlusion force (COF), asymmetry index of molar occlusal force(AMOF). Balanced muscles of mastication measuring standards were also obtained including measurements from electromyogram for the muscles of mastication and the anterior bundle of the temporalis muscle at the mandibular rest position, average electromyogram measurements of the anterior bundle of the temporalis muscle at the intercuspal position(ICP), Astot, masseter muscle asymmetry index, and anterior temporalis asymmetry index (ASTA). Statistical analysis was performed using Student 's t test with SPSS 18.0 software package. Three months after occlusion adjustment, parameters of the original occlusion adjustment method were significantly different between group A and group B in balanced occlusal measuring standards and balanced muscles of mastication measuring standards. Six months after occlusion adjustment, parameters of the original occlusion adjustment methods were significantly different between group A and group B in balanced muscles of mastication measuring standards, but was no significant difference in balanced

Long-term success of endovascular treatment of benign superior vena cava occlusion with chylothorax and chylopericardium

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Veroux, Pierfrancesco; Veroux, Massimiliano; Bonanno, Maria Giovanna; Tumminelli, Maria Giuseppina [Department of Surgery and Transplantation, University Hospital, Via S. Sofia, 78, 95123 Catania (Italy); Baggio, Elda [Department of Surgery and Gastroenterological Sciences, University Hospital of Verona (Italy); Petrillo, Giuseppe [Department of Radiology, University Hospital, Via S. Sofia, 78, 95123 Catania (Italy)

2002-07-01

The most likely etiology of benign obstruction of the superior vena cava (SVC) include fibrosing mediastinitis and iatrogenic etiologies such as sclerosis and obstruction caused by pacemakers and central venous catheter. Percutaneous stenting of SVC has been used with success both in malignant and benign superior vena cava syndrome; however, long-term follow-up of endovascular procedures is not well known. We present a case of a patient with complete occlusion of SVC of benign etiology, presenting dramatically with bilateral chylothorax and chylopericardium with cardiac tamponade, who underwent successful vena caval revascularization with thrombolytic therapy and placement of self-expanding metallic stent. The 42-month follow-up could encourage endovascular procedures even in SVC syndrome of benign etiology. (orig.)

One-year clinical evaluation of nanohybrid resin composite in the restoration of occlusal and proximo-occlusal cavities in Nigeria

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Lillian Lami Enone

2017-01-01

Full Text Available Background: This study aimed to evaluate the clinical performance of nanocomposites in a Nigerian adult population. Resin composites are becoming the preferred direct restorative material in restoring occlusal and proximo-occlusal cavities due to their aesthetic properties and good clinical service. Materials and Methods: This was a clinical study evaluating the clinical performance of a nanohybrid resin composite in the restoration of occlusal and proximo-occlusal cavities in Nigerian adults. This study was done in the Conservative Dentistry Clinic of the Lagos State University Teaching Hospital, Ikeja, from April 2014 to September 2015. The restorations were evaluated immediately at baseline, 3, 6 and 12 months postoperatively for colour match, marginal discolouration, surface roughness, anatomical form, marginal adaptation, retention, post-operative sensitivity and secondary caries using the modified USPHS criteria. Statistical analysis was performed using Fisher's exact test and a 5% level of significance was considered statistically significant. Results: Males had more proximo-occlusal (26.7 than occlusal (6.7 cavities while the females (43.3 had more occlusal cavities. The nanohybrid occlusal restorations had 100% alpha scores at baseline for anatomical form which dropped to 93.3% at 12 months with 6.7% of the restorations scoring Bravo, whereas all nanohybrid proximo-occlusal restorations had 100% alpha scores from baseline to the 12-month review. All occlusal and proximo-occlusal restorations evaluated for surface texture and marginal adaptation had alpha scores at baseline which dropped to 93.3% at 12 months. Conversely, all nanohybrid occlusal and proximo-occlusal restorations scored 100% for colour match and retention, sensitivity and secondary caries from baseline to 12 months. Conclusion: The clinical performance of natural elegance nanohybrid resin composite (Henry Schein® was satisfactory in the restoration of occlusal and

Recurrence of amblyopia after occlusion therapy.

Science.gov (United States)

Bhola, Rahul; Keech, Ronald V; Kutschke, Pamela; Pfeifer, Wanda; Scott, William E

2006-11-01

To determine the stability of visual acuity (VA) after a standardized occlusion regimen in children with strabismic and/or anisometropic amblyopia. Retrospective, population-based, consecutive observational case series. Four hundred forty-nine patients younger than 10 years who underwent an occlusion trial for amblyopia and were observed until there was a recurrence of amblyopia or for a maximum of 1 year after decrease or cessation of occlusion therapy. We performed a retrospective chart review of all patients treated by occlusion therapy for strabismic and/or anisometropic amblyopia at our institution over a 34-year period. Of the 1621 patients identified in our database, 449 met the eligibility criteria and were included in this study. Patients having at least a 2 logarithm of the minimum angle of resolution (logMAR)-level improvement in VA by optotypes or a change from unmaintained to maintained fixation preference during the course of occlusion therapy were included. A recurrence of amblyopia was defined as > or =2 logMAR levels of VA reduction or reversal of fixation preference within 1 year after a decrease or cessation of occlusion therapy. Recurrence of amblyopia after a decrease or cessation of occlusion therapy and its relationship with patient age and VA of the amblyopic eye at the time of decrease or cessation of occlusion therapy. Of 653 occlusion trials, 179 (27%) resulted in recurrence of amblyopia. The recurrence was found to be inversely correlated with patient age. There was no statistically significant association between the recurrence of amblyopia and VA of the amblyopic eye at the end of maximal occlusion therapy. There is a clinically important risk of amblyopia recurrence when occlusion therapy is decreased before the age of 10 years. The risk of recurrence is inversely correlated with age (P<0.0001).

Saphenous Venous Ablation with Hot Contrast in a Canine Model

International Nuclear Information System (INIS)

Prasad, Amit; Qian Zhong; Kirsch, David; Eissa, Marna; Narra, Pavan; Lopera, Jorge; Espinoza, Carmen G.; Castaneda, Wifrido

2008-01-01

Purpose. To determine the feasibility, efficacy, and safety of thermal ablation of the saphenous vein with hot contrast medium. Methods. Twelve saphenous veins of 6 dogs were percutaneously ablated with hot contrast medium. In all animals, ablation was performed in the vein of one leg, followed by ablation in the contralateral side 1 month later. An occlusion balloon catheter was placed in the infragenicular segment of the saphenous vein via a jugular access to prevent unwanted thermal effects on the non-target segment of the saphenous vein. After inflation of the balloon, 10 ml of hot contrast medium was injected under fluoroscopic control through a sheath placed in the saphenous vein above the ankle. A second 10 ml injection of hot contrast medium was made after 5 min in each vessel. Venographic follow-up of the ablated veins was performed at 1 month (n = 12) and 2 months (n = 6). Results. Follow-up venograms showed that all ablated venous segments were occluded at 1 month. In 6 veins which were followed up to 2 months, 4 (66%) remained occluded, 1 (16%) was partially patent, and the remaining vein (16%) was completely patent. In these latter 2 cases, an inadequate amount of hot contrast was delivered to the lumen due to a closed balloon catheter downstream which did not allow contrast to displace blood within the vessel. Discussion. Hot contrast medium thermal ablation of the saphenous vein appears feasible, safe, and effective in the canine model, provided an adequate amount of embolization agent is used

Evaluation of bone loss due to primary occlusal trauma in two experimental models of occlusal overload

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Ana Cristina Távora de Albuquerque LOPES

Full Text Available Abstract Introduction Primary occlusal trauma (OT is an injury of the periodontium with normal height as a result of occlusal forces which exceed their adaptive capacity. Objective To evaluate, histometrically, the alveolar bone loss in the furcation region of rats experimentally submitted to 2 models of occlusal overload. Material and method 45 animals randomly divided into 3 groups: Occlusal Interference (OI, n = 15 - fixing an orthodontic wire segment on the occlusal surface of the first lower molar; Occlusal Overload (OO, n = 15 - wearing of the cusps of the lower contralateral molars, the second and third molars next to the first molar that had its dimensions maintained; Negative Control (NC, n = 15 - evaluation of the initial dimensions of the periodontal ligament (PL. Five animals / group were sacrificed after 14, 21 and 28 days. Result Intergroup evaluation showed significant bone loss in OI (p0.05. The thickness of the PL remained stable in NC (p>0.05. Conclusion OI and OO were effective in the experimental reproduction of OT, and OI promoted greater alveolar bone loss compared to OO, showing that the impact of occlusal overload in OI increased the extent of the OT injury.

Occlusion effects, Part I

DEFF Research Database (Denmark)

Hansen, Mie Østergaard

annoyances and the objective measurements were analysed. Persons suffering from tinnitus behaved differently than person without tinnitus. The latter group showed significant relations between the measured occlusion effect, hearing loss and the personal of occlusion. The actual sensation level is also...

Cytomegalovirus retinitis after central retinal vein occlusion in a patient on systemic immunosuppression: does venooclusive disease predispose to cytomegalovirus retinitis in patients already at risk?

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Welling JD

2012-04-01

Full Text Available John D Welling, Ahmad B Tarabishy, John ChristoforidisDepartment of Ophthalmology, Havener Eye Institute, Ohio State University, Columbus, OH, USAAbstract: Cytomegalovirus (CMV retinitis remains the most common opportunistic ocular infection in immunocompromised patients. Patients with immunocompromising diseases, such as acquired immunodeficiency syndrome, inherited immunodeficiency states, malignancies, and those on systemic immunosuppressive therapy, are known to be at risk. Recently, it has been suggested that patients undergoing intravitreal injection of immunosuppressive agents may also be predisposed. One previous case report speculated that there may be an additional risk for CMV retinitis in acquired immunodeficiency syndrome patients with venoocclusive disease. This case study presents a case of CMV retinitis following central retinal vein occlusion in a patient on systemic immunosuppressants.Keywords: cytomegalovirus retinitis, central retinal vein occlusion, immunosuppression, solid organ transplant, venous stasis, risk factor

[Temporomandibular joint, occlusion and bruxism].

Science.gov (United States)

Orthlieb, J D; Ré, J P; Jeany, M; Giraudeau, A

2016-09-01

Temporomandibular joint and dental occlusion are joined for better and worse. TMJ has its own weaknesses, sometimes indicated by bad functional habits and occlusal disorders. Occlusal analysis needs to be addressed simply and clearly. The term "malocclusion" is not reliable to build epidemiological studies, etiologic mechanisms or therapeutic advice on this "diagnosis". Understanding the impact of pathogenic malocclusion is not just about occlusal relationships that are more or less defective, it requires to locate them within the skeletal framework, the articular and behavioural context of the patient, and above all to assess their impact on the functions of the masticatory system. The TMJ-occlusion couple is often symbiotic, developing together in relation to its environment, compensating for its own shortcomings. However, a third partner may alter this relationship, such as bruxism, or more generally oral parafunctions, trauma or an interventionist practitioner. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Femoral venous oxygen saturation is no surrogate for central venous oxygen saturation

NARCIS (Netherlands)

van Beest, Paul A.; van der Schors, Alice; Liefers, Henriëtte; Coenen, Ludo G. J.; Braam, Richard L.; Habib, Najib; Braber, Annemarije; Scheeren, Thomas W. L.; Kuiper, Michaël A.; Spronk, Peter E.

2012-01-01

Objective: The purpose of our study was to determine if central venous oxygen saturation and femoral venous oxygen saturation can be used interchangeably during surgery and in critically ill patients. Design: Prospective observational controlled study. Setting: Nonacademic university-affiliated

Treatment of temporomandibular disorder using occlusal splint

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Agus Dahlan

2009-03-01

Full Text Available Background: Patient suffering from occlusal abnormality is usually detected months or even years when the acute patient visits a dentist, and generally the patient does not receive direct treatment upon his complaints since minimum information is available on this type of treatment. In general, the dentist provides medication only or conducts incorrect selective grinding where in fact, the patient does not feel better from the previous conditions. Purpose: The objective of this study is to discuss the treatment on the dysfunctional temporomandibular joint followed by orofacial pain caused by occlusal disorder using occlusal splint. Case: In this case, a forty three years old male having trouble with the joint on the left jaw followed by orofacial pain caused by occlusal disorder. Case Management: Initial treatment with occlusal splint makes the patient comfortable and recovers from his complaints since the patient could restructure the chewing muscles. This treatment will be more successful if the dentist has the knowledge to use and choose occlusal splint method properly. Occlusal Splint could be used as a supporting therapy and consideration as one of the therapies to avoid the unwanted side effects. The use of occlusal splint is meant as an alternative of the main therapy in overcoming the problem of occlusal splint. Conclusion: Finally, therapy with occlusal splint is very effective as an alternative treatment to handle the dysfunction of temporomandibular joint caused by occlusion.

Hydrogel based occlusion systems

NARCIS (Netherlands)

Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y.; Engel, L.; Krylov, V.

2013-01-01

A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a

Femoral venous oxygen saturation is no surrogate for central venous oxygen saturation

NARCIS (Netherlands)

van Beest, Paul A.; van der Schors, Alice; Liefers, Henriette; Coenen, Ludo G. J.; Braam, Richard L.; Habib, Najib; Braber, Annemarije; Scheeren, Thomas W. L.; Kuiper, Michael A.; Spronk, Peter E.

2012-01-01

Objective:  The purpose of our study was to determine if central venous oxygen saturation and femoral venous oxygen saturation can be used interchangeably during surgery and in critically ill patients. Design:  Prospective observational controlled study. Setting:  Nonacademic university-affiliated

Protocol for the realization of venous mapping by chronic venous insufficiency in lower limbs under sonographic guide

International Nuclear Information System (INIS)

Blanco Rojas, Diego Jose

2013-01-01

The current state of knowledge is reviewed with respect to the realization of lower limbs venous mapping. Venous mapping is obtained by the use of color and spectral Doppler ultrasound. Doppler ultrasound has provided a precise graphical representation of the superficial and deep venous systems. The performance of the venous mapping is considered essential for the correct handling of venous diseases. The anatomical and pathophysiological basic concepts are defined to realize the sonographic assessment of the veins of the lower limbs. The required technical aspects are revised for the realization of sonographic exploration of the patient with venous insufficiency. Sonographic findings are characterized to support the diagnostic of venous insufficiency of the lower limbs. The CEAP (clinical-etiologic-anatomic-pathophysiologic) classification is utilized to differentiate forms and degrees of severity of the disorder, and has allowed an interinstitutional comparison in clinical studies, the evaluation of treatment and monitoring of patients. A proposal is designed to perform reports that have served of guide surgical to vascular surgeons [es

Human cerebral venous outflow pathway depends on posture and central venous pressure

DEFF Research Database (Denmark)

Gisolf, J; van Lieshout, J J; van Heusden, K

2004-01-01

Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and during a Valsalva manoeuvre in both body positions, correlate highly with model simulation of the jugular cross-sectional area (R(2) = 0.97). The results suggest that the cerebral venous flow distribution depends on posture and CVP: in supine humans the internal jugular veins are the primary pathway...

Colorectal cancer with venous tumor thrombosis

OpenAIRE

Kensuke Otani; Soichiro Ishihara; Keisuke Hata; Koji Murono; Kazuhito Sasaki; Koji Yasuda; Takeshi Nishikawa; Toshiaki Tanaka; Tomomichi Kiyomatsu; Kazushige Kawai; Hiroaki Nozawa; Hironori Yamaguchi; Toshiaki Watanabe

2018-01-01

Summary: Colorectal cancer is seldom accompanied by venous tumor thrombosis, and little is known about the features of venous tumor thrombosis in colorectal cancer. However, some reports show that colorectal cancer patients can develop venous tumor thrombosis and warn clinicians not to overlook this complication. In this report, we perform a review of 43 previously reported cases and investigate the characteristics of colorectal cancer accompanied by venous tumor thrombosis. The histological ...

Postural stability and occlusal status among Japanese elderly.

Science.gov (United States)

Song-Yu, Xuan; Rodis, Omar M M; Ogata, Sagiri; Can-Hu, Jin; Nishimura, Michiko; Matsumura, Seishi

2012-06-01

There are still no data available on the relationship between postural stability and occlusal status among the elderly. To examine relationships between postural stability and occlusal status through a cohort study among elderly Japanese. Oral examination, occlusal status, postural stability and a questionnaire were conducted and given to 87 community-dwelling Japanese at enrolment. The average occlusal pressure of the female group was statistically higher than the male group while average occlusal pressure and postural stability length were lesser in the group with more remaining teeth. Postural stability area and number of remaining teeth showed statistically significant correlations. Postural stability length was lesser in the group with strong occlusal force. Furthermore, the number of decayed teeth was fewer in the good hygiene group. This study identified a close relationship between occlusal status and postural stability of Japanese older individuals. Occlusal hypofunction was observed more in those with occlusal problems, and a decrease in their occlusal functions resulted in postural instability. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Diagnosis and endovascular treatment of multiple cerebral venous and venous sinuses thrombosis

International Nuclear Information System (INIS)

Li Baomin; Zhang Ji; Yin Ling; Huang Xusheng; Jiang Jinli; Liu Jun; Lang Senyang; Zhou Dingbiao; Zhu Ke

2000-01-01

Objective: Eighty-five cases with multiple cerebral venous and venous sinuses thrombosis including the diagnosis and endovascular therapy were reported. Methods: The long T2 and short T1 signals in the related regions of multiple venous sinuses on MRI and prolonged blood circulation time of the brain with tortuous dilatation of vein in angiography were the important characteristics for the diagnosis. Of the 85 cases, the treatment procedures were consisted of injecting urokinase intermittently via common carotid artery and intra-sinus contact thrombolysis as well as warfarin intake orally. Results: Intracranial pressure of 80 cases reduced down between 230 and 300 mm H 2 O, and clinical deficits were markedly improved within 10 days. Re-angiography of 18 cases revealed recanalization partly in 5 cases and circulation time appeared near normal i 8 cases during one week after therapy. Conclusions: Combined intraarterial thrombolysis consecutively with general anticoagulation for the treatment of multiple thrombosis in cerebral venous sinuses may be one of the effective means

Comparison of transient arterial occlusion and muscle exercise provocation for assessment of perfusion reserve in skeletal muscle with real-time contrast-enhanced ultrasound

International Nuclear Information System (INIS)

Krix, Martin; Krakowski-Roosen, Holger; Armarteifio, Erick; Fuerstenberger, Susanne; Delorme, Stefan; Kauczor, Hans-Ulrich; Weber, Marc-Andre

2011-01-01

Objective: Contrast-enhanced ultrasound (CEUS) is able to quantify muscle perfusion and changes in perfusion due to muscle exercise in real-time. However, reliable measurement of standardized muscle exercise is difficult to perform in clinical examinations. We compared perfusion reserve assessed by CEUS after transient arterial occlusion and exercise to find the most suitable measurement for clinical application. Methods: Contrast pulse sequencing (7 MHz) during continuous IV infusion of SonoVue (4.8 mL/300 s) was used in 8 healthy volunteers to monitor muscle perfusion of the gastrocnemius muscle during transient (1 min) arterial occlusion produced by a thigh cuff of a venous occlusion plethysmograph. Isometric muscle exercise (50% of individual maximum strength for 20 s) was subsequently performed during the same examination, and several CEUS parameters obtained from ultrasound-signal-intensity-time curves and its calculation errors were compared. Results: The mean maximum local blood volume after occlusion was 13.9 [∼mL] (range, 4.5-28.8 [∼mL]), and similar values were measured after sub-maximum exercise 13.8 [∼mL], (range, 4.6-22.2 [∼mL]. The areas under the curve during reperfusion vs. recovery were also similar (515.2 ± 257.5 compared to 482.2 ± 187.5 [∼mL s]) with a strong correlation (r = 0.65), as were the times to maximum (15.3 s vs. 15.9 s), with a significantly smaller variation for the occlusion method (±2.1 s vs. ±9.0 s, p = 0.03). The mean errors for all calculated CEUS parameters were lower for the occlusion method than for the exercise test. Conclusions: CEUS muscle perfusion measurements can be easily performed after transient arterial occlusion. It delivers data which are comparable to CEUS measurements after muscle exercise but with a higher robustness. This method can be easily applied in clinical examination of patients with e.g. PAOD or diabetic microvessel diseases to assess perfusion reserve.

Regional cerebral blood flow using sup 133 Xenon intra-venous technique, 2; Evaluation of regional cerebral blood flow in patients with cerebrovascular ischemic disease

Energy Technology Data Exchange (ETDEWEB)

Yonekura, Masahiro; Teramoto, Shigeyoshi; Moriyama, Tadayoshi (Nagasaki Chuo National Hospital (Japan))

1990-12-01

Using the {sup 133}Xenon venous method, we have studied the regional cerebral blood flow (rCBF) in 947 patients with cerebrovascular ischemic disease. In 116 stroke or TIA patients with internal carotid artery occlusion or severe stenosis, their rCBF revealed 48.9 ml/100 g/min on average in the group of one side occlusion, 46.7 ml/100 g/min in the group of both sides occlusion. These values reduced approximately 12%, 16% and 15% of the rCBF in healthy volunteers of same age, respectively. In 28 patients with moya moya disease, their rCBF tended to be higher in younger cases and lower with advanced age. In the majority of the cases, their rCBF was age-dependent with 20{similar to}25 ml/100 g/min below the curve of age-matched rCBF of healthy volunteers. The reduction of rCBF was observed in 69 (48.3%) of 143 cases clinically diagnosed as small vessel disease, in 58 (41.4%) of 140 cases with vertebro-basilar insufficiency and in 23 (44.2%) of 52 cases with syncopal attack compared with the rCBF of healthy volunteers. (author).

Pathophysiology of Venous Thromboembolism with Respect to the Anatomical Features of the Deep Veins of Lower Limbs: A Review.

Science.gov (United States)

Ro, Ayako; Kageyama, Norimasa; Mukai, Toshiji

2017-06-25

Here the pathophysiology of venous thromboembolism is reviewed with respect to the anatomical features of the deep veins of lower limbs. A thrombus is less likely to form in the thigh veins compared with that in the calf veins; however, clinical symptoms are more likely to appear in the thigh veins owing to vascular occlusion. When a patient is bedridden, thrombosis is more likely to occur in the intramuscular vein, which mainly depends on muscular pumping and the venous valve, rather than in the three crural branches, which mainly depends on the pulsation of the accompanying artery. Thrombi are prone to be generated in the soleal vein compared with those in the gastrocnemius vein because of the vein and muscle structures. A soleal vein thrombosis grows toward the proximal veins along the drainage veins. To prevent a sudden pulmonary thromboembolism-related death in bedridden patients, preventing soleal vein thrombus formation and observing the thrombus proximal propagation via the drainage veins are clinically important. When deep vein thrombosis occurs, avoiding embolization and sequela caused by the thrombus organization is necessary.

Microneurografia e pletismografia de oclusão venosa na insuficiência cardíaca: correlação com prognóstico Microneurografía y pletismografía de oclusión venosa en la insuficiencia cardiaca: correlación con pronóstico Microneurography and venous occlusion plethysmography in heart failure: correlation with prognosis

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Robinson Tadeu Munhoz

2009-01-01

Full Text Available FUNDAMENTO: Microneurografia e pletismografia de oclusão venosa podem ser considerados métodos de avaliação da atividade simpática. OBJETIVO: Avaliar a intensidade da atividade simpática através da microneurografia e da pletismografia de oclusão venosa em pacientes com insuficiência cardíaca, e correlacionar essa intensidade com prognóstico. MÉTODOS: 52 pacientes com insuficiência cardíaca (FE 53,5 impulsos/min para ANSM (S=90,55. E=73,68% e 1,81 ml/min/100gr (PFUNDAMENTO: Microneurografía y pletismografía de oclusión venosa se pueden considerar como métodos de evaluación de la actividad simpática. OBJETIVO: Evaluar la intensidad de la actividad simpática a través de la microneurografía y de la pletismografía de oclusión venosa en pacientes con insuficiencia cardiaca, y correlacionar esa intensidad con pronóstico. MÉTODOS: Un total de 52 pacientes con insuficiencia cardiaca (FE 53,5 impulsos/min para ANSM (S=90,55. E=73,68% y 1,81 ml/min/100gr (PBACKGROUND: Microneurography and venous occlusion plethysmography can be considered methods of assessment of the sympathetic activity. OBJECTIVE: To evaluate the intensity of the sympathetic activity through microneurography and venous occlusion plethysmography in patients with heart failure (HF and correlate this intensity with prognosis. METHODS: 52 patients with HF (ejection fraction 53.5 impulses/min for MSNA (S=90.55. E=73.68% and 1.81 ml/min/100gr (P<0.001. Logistic regression analysis: the higher the MSNA and the lower the MBF, the higher is the probability of death. CONCLUSION: The intensity of the MSNA and the MBF can be considered prognostic markers in advanced HF.

Plasma Glucose Level Is Predictive of Serum Ammonia Level After Retrograde Occlusion of Portosystemic Shunts.

Science.gov (United States)

Ishikawa, Tsuyoshi; Aibe, Yuki; Matsuda, Takashi; Iwamoto, Takuya; Takami, Taro; Sakaida, Isao

2017-09-01

The purpose of this study was to evaluate predictors of reduction in ammonia levels by occlusion of portosystemic shunts (PSS) in patients with cirrhosis. Forty-eight patients with cirrhosis (21 women, 27 men; mean age, 67.8 years) with PSS underwent balloon-occluded retrograde transvenous obliteration (BRTO) at one institution between February 2008 and June 2014. The causes of cirrhosis were hepatitis B in one case, hepatitis C in 20 cases, alcohol in 15 cases, nonalcoholic steatohepatitis in eight cases, and other conditions in four cases. The Child-Pugh classes were A in 24 cases, B in 23 cases, and C in one case. The indication for BRTO was gastric varices in 40 cases and hepatic encephalopathy in eight cases. Testing was conducted before and 1 month after the procedure. Statistical analyses were performed to identify predictors of a clinically significant decline in ammonia levels after BRTO. Occlusion of PSS resulted in a clinically significant decrease in ammonia levels accompanied by increased portal venous flow and improved Child-Pugh score. Univariate analyses showed that a reduction in ammonia levels due to BRTO was significantly related to lower plasma glucose levels, higher RBC counts, and higher hemoglobin concentration before the treatment. Furthermore, multivariate logistic regression identified preoperative plasma glucose level as the strongest independent predictor of a significant ammonia reduction in response to BRTO. In addition, although BRTO resulted in significantly declined ammonia levels in patients with normal glucose tolerance before the procedure, ammonia levels were not significantly decreased after shunt occlusion in patients with diabetes mellitus or impaired glucose tolerance before BRTO, according to 75-g oral glucose tolerance test results. Preoperative plasma glucose level is a useful predictor of clinically significant ammonia reduction resulting from occlusion of PSS in patients with cirrhosis. Even if PSS are present, control

A new method of evaluating posterior occlusion and its relation to posttreatment occlusal changes.

Science.gov (United States)

Parkinson, C E; Buschang, P H; Behrents, R G; Throckmorton, G S; English, J D

2001-11-01

The purpose of this study was to assess the relationship between posterior occlusion and posttreatment changes in other occlusal variables. Pretreatment (T1), posttreatment (T2), and postretention (T3) records were obtained for 49 Class I (n = 23) and Class II (n = 26) extraction cases. Overbite, overjet, mandibular incisor irregularity, right and left molar deviations, midline deviation, and mandibular arch length were measured, and occlusal registrations were made of each set of dental casts. The proximity of posterior occlusal surfaces was measured as the contact or near-contact areas at or below 300 microm thickness, based on the optical densities of scanned images of the posterior occlusal registrations. The treatment changes for overbite, overjet, right and left molar deviation, and arch length were significantly greater in the Class II group, and the reductions in incisor irregularity were greater in the Class I group. No other class differences were found. Overbite, overjet, and incisor irregularity increased after treatment, and arch length continued to decrease, with no significant class differences. Contact and near-contact areas at or below 300 microm constituted 7% of the functional occlusal table for both classes at the end of treatment, having decreased significantly in both groups (21% in Class I and 29% in Class II) during treatment. Because contact and near-contact areas increased in some patients and decreased in others, there were no significant posttreatment changes. Negative correlations were found between contact and near-contact areas at T2 and changes in overjet from T2 to T3, and between contact and near-contact areas at T3 and changes in overbite from T2 to T3. No relationships were found between posterior contact and near-contact area and incisor irregularity. We concluded that (1) the area of actual and near contacts at or below 300 microm decreased significantly with treatment, indicating that, despite excellent treatment results by

Venous abnormalities demonstrated by computed tomography

Energy Technology Data Exchange (ETDEWEB)

Ishikawa, T; Tsukune, Y; Ashida, H; Tokuda, M; Oyama, Y [St. Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

1980-05-01

CT is capable of demonstrating various venous changes. However, little have been described on this subject in the literature. Examples of various venous abnormalities such as obstructed jugular vein, superior and inferior vena cava (IVC), tumor invasion of IVC and renal vein and venous changes in portal hypertension were presented. It was stressed that noninvasive CT is a good tool in diagnosis of some of venous changes and may be able to eliminate angiography in such cases.

Influence of mandibular fixation method on stability of the maxillary occlusal plane after occlusal plane alteration.

Science.gov (United States)

Yosano, Akira; Katakura, Akira; Takaki, Takashi; Shibahara, Takahiko

2009-05-01

In this study, we investigated how method of mandibular fixation influenced longterm postoperative stability of the maxilla in Class III cases. In particular, we investigated change in the maxillary occlusal plane after Occlusal Plane Alteration. Therefore, we focused on change in the palatal plane to evaluate stability of the maxillary occlusal plane, as the position of the palatal plane affects the maxillary occlusal plane. This study included 16 patients diagnosed with mandibular protrusion. Alteration of the occlusal plane was achieved by clockwise rotation of the maxilla by Le Fort I osteotomy and mandibular setback was performed by bilateral sagittal split ramus osteotomy. We analyzed and examined lateral cephalometric radiographs taken at 1 month, 3 months, 6 months, and 1 year after surgery. Stability achieved by two methods of mandibular fixation was compared. In one group of patients (group S) titanium screws were used, and in the other group (group P) titanium-locking mini-plates were used. No significant displacement was recognized in group S, whereas an approximately 0.7mm upward vertical displacement was recognized in the anterior nasal spine in group P. As a result, not only the angle of the palatal plane and S-N plane, but also occlusal plane angle in group P showed a greater decrease than that in group S. The results suggest that fixing the mandible with screws yielded greater stability of the maxilla and maxillary occlusal plane than fixing the mandible with titanium plates.

TIPS Placement via Combined Transjugular and Transhepatic Approach for Cavernous Portal Vein Occlusion: Targeted Approach

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Natanel Jourabchi

2013-01-01

Full Text Available Purpose. We report a novel technique which aided recanalization of an occluded portal vein for transjugular intrahepatic portosystemic shunt (TIPS creation in a patient with symptomatic portal vein thrombosis with cavernous transformation. Some have previously considered cavernous transformation a contraindication to TIPS. Case Presentation. 62-year-old man with chronic pancreatitis, portal vein thrombosis, portal hypertension and recurrent variceal bleeding presents with melena and hematemesis. The patient was severely anemic, hemodynamically unstable, and required emergent portal decompression. Attempts to recanalize the main portal vein using traditional transjugular access were unsuccessful. After percutaneous transhepatic right portal vein access and navigation of a wire through the occluded main portal vein, an angioplasty balloon was inflated at the desired site of shunt takeoff. The balloon was targeted and punctured from the transjugular approach, and a wire was passed into the portal system. TIPS placement then proceeded routinely. Conclusion. Although occlusion of the portal vein increases difficulty of performing TIPS, it should not be considered an absolute contraindication. We have described a method for recanalizing an occluded portal vein using a combined transhepatic and transjugular approach for TIPS. This approach may be useful to relieve portal hypertension in patients who fail endoscopic and/or surgical therapies.

Occlusion Handling in Videos Object Tracking: A Survey

International Nuclear Information System (INIS)

Lee, B Y; Liew, L H; Cheah, W S; Wang, Y C

2014-01-01

Object tracking in video has been an active research since for decades. This interest is motivated by numerous applications, such as surveillance, human-computer interaction, and sports event monitoring. Many challenges related to tracking objects still remain, this can arise due to abrupt object motion, changing appearance patterns of objects and the scene, non-rigid object structures and most significant are occlusion of tracked object be it object-to-object or object-to-scene occlusions. Generally, occlusion in object tracking occur under three situations: self-occlusion, inter-object occlusion by background scene structure. Self-occlusion occurs most frequently while tracking articulated objects when one part of the object occludes another. Inter-object occlusion occurs when two objects being tracked occlude each other whereas occlusion by the background occurs when a structure in the background occludes the tracked objects. Typically, tracking methods handle occlusion by modelling the object motion using linear and non-linear dynamic models. The derived models will be used to continuously predicting the object location when a tracked object is occluded until the object reappears. Example of these method are Kalman filtering and Particle filtering trackers. Researchers have also utilised other features to resolved occlusion, for example, silhouette projections, colour histogram and optical flow. We will present some result from a previously conducted experiment when tracking single object using Kalman filter, Particle filter and Mean Shift trackers under various occlusion situation in this paper. We will also review various other occlusion handling methods that involved using multiple cameras. In a nutshell, the goal of this paper is to discuss in detail the problem of occlusion in object tracking and review the state of the art occlusion handling methods, classify them into different categories, and identify new trends. Moreover, we discuss the important

Occlusion Handling in Videos Object Tracking: A Survey

Science.gov (United States)

Lee, B. Y.; Liew, L. H.; Cheah, W. S.; Wang, Y. C.

2014-02-01

Object tracking in video has been an active research since for decades. This interest is motivated by numerous applications, such as surveillance, human-computer interaction, and sports event monitoring. Many challenges related to tracking objects still remain, this can arise due to abrupt object motion, changing appearance patterns of objects and the scene, non-rigid object structures and most significant are occlusion of tracked object be it object-to-object or object-to-scene occlusions. Generally, occlusion in object tracking occur under three situations: self-occlusion, inter-object occlusion by background scene structure. Self-occlusion occurs most frequently while tracking articulated objects when one part of the object occludes another. Inter-object occlusion occurs when two objects being tracked occlude each other whereas occlusion by the background occurs when a structure in the background occludes the tracked objects. Typically, tracking methods handle occlusion by modelling the object motion using linear and non-linear dynamic models. The derived models will be used to continuously predicting the object location when a tracked object is occluded until the object reappears. Example of these method are Kalman filtering and Particle filtering trackers. Researchers have also utilised other features to resolved occlusion, for example, silhouette projections, colour histogram and optical flow. We will present some result from a previously conducted experiment when tracking single object using Kalman filter, Particle filter and Mean Shift trackers under various occlusion situation in this paper. We will also review various other occlusion handling methods that involved using multiple cameras. In a nutshell, the goal of this paper is to discuss in detail the problem of occlusion in object tracking and review the state of the art occlusion handling methods, classify them into different categories, and identify new trends. Moreover, we discuss the important

The Kallikrein Inhibitor from Bauhinia bauhinioides (BbKI) shows antithrombotic properties in venous and arterial thrombosis models.

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Brito, Marlon V; de Oliveira, Cleide; Salu, Bruno R; Andrade, Sonia A; Malloy, Paula M D; Sato, Ana C; Vicente, Cristina P; Sampaio, Misako U; Maffei, Francisco H A; Oliva, Maria Luiza V

2014-05-01

The Bauhinia bauhinioides Kallikrein Inhibitor (BbKI) is a Kunitz-type serine peptidase inhibitor of plant origin that has been shown to impair the viability of some tumor cells and to feature a potent inhibitory activity against human and rat plasma kallikrein (Kiapp 2.4 nmol/L and 5.2 nmol/L, respectively). This inhibitory activity is possibly responsible for an effect on hemostasis by prolonging activated partial thromboplastin time (aPTT). Because the association between cancer and thrombosis is well established, we evaluated the possible antithrombotic activity of this protein in venous and arterial thrombosis models. Vein thrombosis was studied in the vena cava ligature model in Wistar rats, and arterial thrombosis in the photochemical induced endothelium lesion model in the carotid artery of C57 black 6 mice. BbKI at a concentration of 2.0 mg/kg reduced the venous thrombus weight by 65% in treated rats in comparison to rats in the control group. The inhibitor prolonged the time for total artery occlusion in the carotid artery model mice indicating that this potent plasma kallikrein inhibitor prevented thrombosis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Occlusion-Aware View Interpolation

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Ince Serdar

2008-01-01

Full Text Available Abstract View interpolation is an essential step in content preparation for multiview 3D displays, free-viewpoint video, and multiview image/video compression. It is performed by establishing a correspondence among views, followed by interpolation using the corresponding intensities. However, occlusions pose a significant challenge, especially if few input images are available. In this paper, we identify challenges related to disparity estimation and view interpolation in presence of occlusions. We then propose an occlusion-aware intermediate view interpolation algorithm that uses four input images to handle the disappearing areas. The algorithm consists of three steps. First, all pixels in view to be computed are classified in terms of their visibility in the input images. Then, disparity for each pixel is estimated from different image pairs depending on the computed visibility map. Finally, luminance/color of each pixel is adaptively interpolated from an image pair selected by its visibility label. Extensive experimental results show striking improvements in interpolated image quality over occlusion-unaware interpolation from two images and very significant gains over occlusion-aware spline-based reconstruction from four images, both on synthetic and real images. Although improvements are obvious only in the vicinity of object boundaries, this should be useful in high-quality 3D applications, such as digital 3D cinema and ultra-high resolution multiview autostereoscopic displays, where distortions at depth discontinuities are highly objectionable, especially if they vary with viewpoint change.

Occlusion-Aware View Interpolation

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Janusz Konrad

2009-01-01

Full Text Available View interpolation is an essential step in content preparation for multiview 3D displays, free-viewpoint video, and multiview image/video compression. It is performed by establishing a correspondence among views, followed by interpolation using the corresponding intensities. However, occlusions pose a significant challenge, especially if few input images are available. In this paper, we identify challenges related to disparity estimation and view interpolation in presence of occlusions. We then propose an occlusion-aware intermediate view interpolation algorithm that uses four input images to handle the disappearing areas. The algorithm consists of three steps. First, all pixels in view to be computed are classified in terms of their visibility in the input images. Then, disparity for each pixel is estimated from different image pairs depending on the computed visibility map. Finally, luminance/color of each pixel is adaptively interpolated from an image pair selected by its visibility label. Extensive experimental results show striking improvements in interpolated image quality over occlusion-unaware interpolation from two images and very significant gains over occlusion-aware spline-based reconstruction from four images, both on synthetic and real images. Although improvements are obvious only in the vicinity of object boundaries, this should be useful in high-quality 3D applications, such as digital 3D cinema and ultra-high resolution multiview autostereoscopic displays, where distortions at depth discontinuities are highly objectionable, especially if they vary with viewpoint change.

Nitrosylated hemoglobin levels in human venous erythrocytes correlate with vascular endothelial function measured by digital reactive hyperemia.

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Irina I Lobysheva

Full Text Available Impaired nitric oxide (NO-dependent endothelial function is associated with the development of cardiovascular diseases. We hypothesized that erythrocyte levels of nitrosylated hemoglobin (HbNO-heme may reflect vascular endothelial function in vivo. We developed a modified subtraction method using Electron Paramagnetic Resonance (EPR spectroscopy to identify the 5-coordinate α-HbNO (HbNO concentration in human erythrocytes and examined its correlation with endothelial function assessed by peripheral arterial tonometry (PAT. Changes in digital pulse amplitude were measured by PAT during reactive hyperemia following brachial arterial occlusion in a group of healthy volunteers (50 subjects. Erythrocyte HbNO levels were measured at baseline and at the peak of hyperemia. We digitally subtracted an individual model EPR signal of erythrocyte free radicals from the whole EPR spectrum to unmask and quantitate the HbNO EPR signals.Mean erythrocyte HbNO concentration at baseline was 219+/-12 nmol/L (n = 50. HbNO levels and reactive hyperemia (RH indexes were higher in female (free of contraceptive pills than male subjects. We observed a dynamic increase of HbNO levels in erythrocytes isolated at 1-2 min of post-occlusion hyperemia (120+/-8% of basal levels; post-occlusion HbNO levels were correlated with basal levels. Both basal and post-occlusion HbNO levels were significantly correlated with reactive hyperemia (RH indexes (r = 0.58; P<0.0001 for basal HbNO.The study demonstrates quantitative measurements of 5-coordinate α-HbNO in human venous erythrocytes, its dynamic physiologic regulation and correlation with endothelial function measured by tonometry during hyperemia. This opens the way to further understanding of in vivo determinants of NO bioavailability in human circulation.

Factor XI and XII as antithrombotic targets.

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Müller, Felicitas; Gailani, David; Renné, Thomas

2011-09-01

Arterial and venous thrombosis are major causes of morbidity and mortality, and the incidence of thromboembolic diseases increases as a population ages. Thrombi are formed by activated platelets and fibrin. The latter is a product of the plasma coagulation system. Currently available anticoagulants such as heparins, vitamin K antagonists and inhibitors of thrombin or factor Xa target enzymes of the coagulation cascade that are critical for fibrin formation. However, fibrin is also necessary for terminating blood loss at sites of vascular injury. As a result, anticoagulants currently in clinical use increase the risk of bleeding, partially offsetting the benefits of reduced thrombosis. This review focuses on new targets for anticoagulation that are associated with minimal or no therapy-associated increased bleeding. Data from experimental models using mice and clinical studies of patients with hereditary deficiencies of coagulation factors XI or XII have shown that both of these clotting factors are important for thrombosis, while having minor or no apparent roles in processes that terminate blood loss (hemostasis). Hereditary deficiency of factor XII (Hageman factor) or factor XI, plasma proteases that initiate the intrinsic pathway of coagulation, impairs thrombus formation and provides protection from vascular occlusive events, while having a minimal impact on hemostasis. As the factor XII-factor XI pathway contributes to thrombus formation to a greater extent than to normal hemostasis, pharmacological inhibition of these coagulation factors may offer the exciting possibility of anticoagulation therapies with minimal or no bleeding risk.

Diagnostic value of color doppler ultrasonography in detecting stenosis and occlusion of central veins in patients with chronic kidney disease

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Masoud Pezeshki Rad

2015-01-01

Full Text Available Venography is an invasive diagnostic test that uses contrast material that provides a picture of the condition of the veins. But, complications, including adverse effects on the kidney, do occur. On the other hand, with the current technological development, application of ultrasound in the diagnosis of obstructive diseases of the veins is gaining popularity, being non-invasive, easy to perform and cost-effective. The aim of this study was to evaluate the diagnostic value of Doppler sonography in the diagnosis of central vein stenosis. In this descriptive-analytical study, 41 hemodialysis patients who had been referred for 50 upper limb venographies to the radiology department of Imam Reza (AS were included. Patients with chronic kidney disease with a history of catheterization of the vein, jugular or subclavian, and who had established fistulas or synthetic vascular grafts were targeted. Central venous ultrasound was performed on both sides to evaluate stenosis or occlusion. Venography was performed by the radiologist the next day or the day before hemodialysis. Data on demographic characteristics, findings of clinical examination and findings of ultrasound as well as venography were recorded by using the SPSS software, Chi-square test and Spearman correlation, and Kappa agreement was calculated for sensitivity, specificity and predictive values. Twenty-three (56% patients were male subjects and 18 patients (44% were female. Twenty-three (56% patients of the study population were aged 60 years. The overall sensitivity, specificity and positive predictive value and negative predictive value of Doppler sonography in the proximal veins in hemodialysis patients compared with venography were, respectively, 80.9%, 79.3%, 73.9% and 85.1%. Color Doppler sonography, as a non-invasive method, could be a good alternative for venography in the assessment of the upper limb with central vein stenosis and occlusion.

Diagnostic value of color doppler ultrasonography in detecting stenosis and occlusion of central veins in patients with chronic kidney disease.

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Rad, Masoud Pezeshki; Kazemzadeh, Gholam Hosain; Ziaee, Masood; Azarkar, Ghodsieh

2015-03-01

Venography is an invasive diagnostic test that uses contrast material that provides a picture of the condition of the veins. But, complications, including adverse effects on the kidney, do occur. On the other hand, with the current technological development, application of ultrasound in the diagnosis of obstructive diseases of the veins is gaining popularity, being non-invasive, easy to perform and cost-effective. The aim of this study was to evaluate the diagnostic value of Doppler sonography in the diagnosis of central vein stenosis. In this descriptive-analytical study, 41 hemodialysis patients who had been referred for 50 upper limb venographies to the radiology department of Imam Reza (AS) were included. Patients with chronic kidney disease with a history of catheterization of the vein, jugular or subclavian, and who had established fistulas or synthetic vascular grafts were targeted. Central venous ultrasound was performed on both sides to evaluate stenosis or occlusion. Venography was performed by the radiologist the next day or the day before hemodialysis. Data on demographic characteristics, findings of clinical examination and findings of ultrasound as well as venography were recorded by using the SPSS software, Chi-square test and Spearman correlation, and Kappa agreement was calculated for sensitivity, specificity and predictive values. Twenty-three (56%) patients were male subjects and 18 patients (44%) were female. Twenty-three (56%) patients of the study population were aged 60 years. The overall sensitivity, specificity and positive predictive value and negative predictive value of Doppler sonography in the proximal veins in hemodialysis patients compared with venography were, respectively, 80.9%, 79.3%, 73.9% and 85.1%. Color Doppler sonography, as a non-invasive method, could be a good alternative for venography in the assessment of the upper limb with central vein stenosis and occlusion.

Retinal venous thrombosis in a young patient with coagulation factor XII deficiency.

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Borrego-Sanz, L; Santos-Bueso, E; Sáenz-Francés, F; Martínez-de-la-Casa, J M; García-Feijoo, J; Gegúndez-Fernández, J A; García-Sánchez, J

2014-08-01

A 35-year-old woman, with no relevant medical history, was referred for sudden vision loss in the left eye. Ophthalmological examination showed best corrected visual acuity of 1.0 in the right eye and 0.3 in left eye, with normal anterior pole and intraocular pressure. Fundus examination of the left eye revealed a venous thrombosis in the superior temporal branch, with dilated and tortuous retinal veins. The patient was referred to the hematology unit for thrombophilia study, and was diagnosed with a coagulation XII or Hageman factor deficiency. The development of retinal vessel occlusions, in patients under 50 years of age, is frequently associated with thrombophilia or hypercoagulability disorders. Factor XII deficiency is a rare condition, and its presence could contribute to a higher risk of thromboembolic events. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Combined oral contraceptives: venous thrombosis.

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de Bastos, Marcos; Stegeman, Bernardine H; Rosendaal, Frits R; Van Hylckama Vlieg, Astrid; Helmerhorst, Frans M; Stijnen, Theo; Dekkers, Olaf M

2014-03-03

Combined oral contraceptive (COC) use has been associated with venous thrombosis (VT) (i.e., deep venous thrombosis and pulmonary embolism). The VT risk has been evaluated for many estrogen doses and progestagen types contained in COC but no comprehensive comparison involving commonly used COC is available. To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives. Electronic databases (Pubmed, Embase, Web of Science, Cochrane, CINAHL, Academic Search Premier and ScienceDirect) were searched in 22 April 2013 for eligible studies, without language restrictions. We selected studies including healthy women taking COC with VT as outcome. The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported.Two independent reviewers extracted data from selected studies. 3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 0.19 and 0.37 per 1 000 person years, in line with previously reported incidences of 0,16 per 1 000 person years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 μg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene

Application of photogrammetry for analysis of occlusal contacts.

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Shigeta, Yuko; Hirabayashi, Rio; Ikawa, Tomoko; Kihara, Takuya; Ando, Eriko; Hirai, Shinya; Fukushima, Shunji; Ogawa, Takumi

2013-04-01

The conventional 2D-analysis methods for occlusal contacts provided limited information on tooth morphology. This present study aims to detect 3D positional information of occlusal contacts from 2D-photos via photogrammetry. We propose an image processing solution for analysis of occlusal contacts and facets via the black silicone method and a photogrammetric technique. The occlusal facets were reconstructed from a 2D-photograph data-set of inter-occlusal records into a 3D image via photogrammetry. The configuration of the occlusal surface was reproduced with polygons. In addition, the textures of the occlusal contacts were mapped to each polygon. DIFFERENCE FROM CONVENTIONAL METHODS: Constructing occlusal facets with 3D polygons from 2D-photos with photogrammetry was a defining characteristic of this image processing technique. It allowed us to better observe findings of the black silicone method. Compared with conventional 3D analysis using a 3D scanner, our 3D models did not reproduce the detail of the anatomical configuration. However, by merging the findings of the inter-occlusal record, the deformation of mandible and the displacement of periodontal ligaments under occlusal force were reflected in our model. EFFECT OR PERFORMANCE: Through the use of polygons in the conversion of 2D images to 3D images, we were able to define the relation between the location and direction of the occlusal contacts and facets, which was difficult to detect via conventional methods. Through our method of making a 3D polygon model, the findings of inter-occlusal records which reflected the jaw/teeth behavior under occlusal force could be observed 3-dimensionally. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Nampt/PBEF/visfatin serum levels: a new biomarker for retinal blood vessel occlusions

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Kaja S

2015-04-01

Full Text Available Simon Kaja,1,* Anna A Shah,1,* Shamim A Haji,1,* Krishna B Patel,1 Yuliya Naumchuk,1 Alexander Zabaneh,1 Bryan C Gerdes,1 Nancy Kunjukunju,1 Nelson R Sabates,1 Michael A Cassell,1 Ron K Lord,1 Kevin P Pikey,1 Abraham Poulose,1 Peter Koulen1,21Vision Research Center, Department of Ophthalmology, 2Department of Basic Medical Science, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, USA*These authors contributed equally to this workAbstract: The main objective of the study was to quantify serum levels of nicotinamide phosphoribosyltransferase (Nampt/pre-B-Cell colony-enhancing factor 1/visfatin in subjects with a history of retinal vascular occlusions (RVOs, disease conditions characterized by pronounced ischemia, and metabolic energy deficits. A case–control study of 18 subjects with a history of RVO as well as six healthy volunteers is presented. Serum Nampt levels were quantified using a commercially available enzyme-linked immunosorbent assay kit. Serum Nampt levels were 79% lower in patients with a history of RVO compared with that in healthy volunteers (P<0.05. There was no statistically significant difference among the types of RVOs, specifically branch retinal vein occlusions (n=7, central retinal vein occlusions (n=5, hemiretinal vein occlusions (n=3, and central retinal artery occlusions (n=3; P=0.69. Further studies are needed to establish the temporal kinetics of Nampt expression and to determine whether Nampt may represent a novel biomarker to identify at-risk populations, or whether it is a druggable target with the potential to ameliorate the long-term complications associated with the condition, ie, macular edema, macular ischemia, neovascularization, and permanent loss of vision.Keywords: Nampt, PBEF, visfatin, nicotinamide phosphoribosyltransferase, pre-B-cell colony-enhancing factor, retinal artery occlusion, retinal vein occlusion, biomarker, retina, vasculature

Current possibilities in occlusal caries management

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Hrvoje Jurić

2013-11-01

Full Text Available Dental caries is a multifactorial disease that affects most populations throughout the world and it is still the primary cause of oral pain and tooth loss. The occlusal surfaces of posterior teeth are the most vulnerable sites for dental caries due to their anatomy. Therefore, the aim of the following article is to summarize current knowledge on occlusal caries development and the possibilities of its prevention. Although the overall caries rate today has fallen for populations in industrialized countries, the rate of occlusal surface caries has not decreased. This may be explained with fact that topically applied fluorides and their mode of action prevent caries better on smooth than on occlusal surfaces. As we know, tooth decay of first permanent molars causes a great deal of different short and long term difficulties for patients. Therefore, there is a continuous need for implementation of programs for caries prevention in permanent teeth. Nowadays, we like to treat our patients by minimally invasive methods. A very important step in our effective preventive treatment is sealing pits and fissures as a cornerstone of occlusal caries management. Reliable assessment of caries activity is also very important for defining treatment needs and plans. A very important decision, which should be made during occlusal caries management, is the selection of restorative material according to the treatment plan. Conclusion. Current possibilities in occlusal caries prevention and management are very effective. Therefore, dentists today do not have any excuse for avoiding the philosophy of Minimally Invasive Dentistry, especially when we talk about caries management of occlusal surfaces in permanent molars.

Venous chest anatomy: clinical implications

International Nuclear Information System (INIS)

Chasen, M.H.; Charnsangavej, C.

1998-01-01

This article provides a practical approach to the clinical implications and importance of understanding the collateral venous anatomy of the thorax. Routine radiography, conventional venography, computed tomography (CT), and magnetic resonance (MR) imaging studies provide correlative anatomic models for the demonstration of how interconnecting collateral vascular networks within the thorax maintain venous stability at all times. Five major systems comprise the collateral venous network of the thorax ( Fig. 1 ). These include the paravertebral, azygos-hemiazygos, internal mammary, lateral thoracic, and anterior jugular venous systems (AJVS). The five systems are presented in the following sequence: (a) a brief introduction to the importance of catheter position and malposition in understanding access to the thoracic venous system, (b) the anatomy of the azygos-hemiazygos systems and their relationship with the paravertebral plexus, (c) the importance of the AJVS, (d) 'loop' concepts interconnecting the internal mammary and azygos-hemiazygos systems by means of the lateral thoracic and intercostal veins, and (e) the interconnecting venous networks on the thoracic side of the thoracoabdominal junction. Certain aspects of the venous anatomy of the thorax will not be discussed in this chapter and include (a) the intra-abdominal anastomoses between the superior and inferior vena cavae (IVC) via the internal mammary, lateral thoracic, and azygos-hemiazygos systems (beyond the scope of this article), (b) potential collateral vessels involving vertebral, parascapular, thyroidal, thymic, and other smaller veins that might anastomose with the major systems, and (c) anatomic variants and pitfalls that may mimic pathologic conditions (space limitations). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

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

Occlusion of Heubner's artery

International Nuclear Information System (INIS)

Sato, Manabu; Kidooka, Minoru

1982-01-01

A case of occlusion of the left Heubner's artery in a right-handed, 51-year-old man is reported. Cardinal clinical features were transient right hemiparesis and mental disturbance, especially intellectual defect. Low density areas were found at CT in the globus pallidus, putamen, anterior limb of the internal capsule and a part of the caudate nucleus. It is well known that the occlusion of the Heubner's artery causes transient motor paresis of upper extremity on the contralaterl side. However, in the case where the Heubner's artery is remarkably well developed when compared with the medial striate arteries as was the case in this patient, it should be noted that the occlusion of the Heubner's artery may well causes grave mental disturbance, in addition. (author)

Occlusal considerations for dental implant restorations.

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Bergmann, Ranier H

2014-01-01

When placed, dental implants are put into an ever-changing oral environment in which teeth can continue to migrate. Yet, the implants themselves are ankylosed. This can lead to occlusal instability. Teeth may continue to erupt, leaving the implants in infraocclusion. Teeth may move mesially away from an implant, requiring modification to close an open contact point. Friction in the connection between teeth and implants can lead to intrusion of teeth and damage to the periodontal attachment apparatus. Implant occlusion with shallow incisal guidance minimizes lateral and tipping forces. Cross-arch stabilization allows the best distribution of occlusal forces. The choice of restorative materials influences long-term occlusal stability.

A retrospective study of a new n-butyl-2-cyanoacrylate glue ablation catheter incorporated with application guiding light for the treatment of venous insufficiency: Twelve-month results.

Science.gov (United States)

Yavuz, Turhan; Acar, Altay Nihat; Aydın, Huseyin; Ekingen, Evren

2018-01-01

Objective This study aims to present the early results of a retrospective study of the use of novel n-butyl-2-cyanoacrylate (VenaBlock)-based nontumescent endovenous ablation with a guiding light for the treatment of patients with varicose veins. Methods Patients with lower limb venous insufficiency were treated with n-butyl-2-cyanoacrylate (VenaBlock Venous Closure System) between April 2016 and July 2016. The study enrolled adults aged 21-70 years with symptomatic moderate to severe varicosities (C2-C4b) and great saphenous vein reflux lasting longer than 0.5 s with great saphenous vein diameter between 5.5 and 15 mm assessed in the standing position. No compression stockings were used after the procedure. Duplex ultrasound imaging and clinical follow-up were performed on the third day, first month, sixth month, and 12th month. Clinical, etiological, anatomical, pathophysiological classification; venous clinical severity score; and completed Aberdeen varicose vein questionnaire were recorded. Results Five hundred thirty-eight patients with great saphenous vein incompetency underwent n-butyl-2-cyanoacrylate ablation. The mean ablation length was 25.69 ± 4.8 cm, and the average amount of n-butyl-2-cyanoacrylate delivered was 0.87 ± 0.15 ml. The mean procedure time was 11.7 ± 4.9 min. Procedural success was 100%, and complete occlusion was observed after treatment and at the third-day follow-up. We observed ecchymosis in five patients (1.00%) at the entry site at the third-day follow-up. Phlebitis was encountered with six (1.20%) patients. No skin pigmentation, hematoma, paresthesia, deep vein thrombosis, or pulmonary embolism was observed. Kaplan-Meier analysis yielded an occlusion rate of 99.4% at the 12-month follow-up. All patients had significant improvement in venous clinical severity score and Aberdeen varicose vein questionnaire scores postoperatively ( p <0.0001). Venous clinical severity score scores decreased from 5.43 ± 0.87 to

Occlusal adjustment using the bite plate-induced occlusal position as a reference position for temporomandibular disorders: a pilot study

Directory of Open Access Journals (Sweden)

Chiwata Ichiro

2010-03-01

Full Text Available Abstract Background Many researchers have not accepted the use of occlusal treatments for temporomandibular disorders (TMDs. However, a recent report described a discrepancy between the habitual occlusal position (HOP and the bite plate-induced occlusal position (BPOP and discussed the relation of this discrepancy to TMD. Therefore, the treatment outcome of evidence-based occlusal adjustments using the bite plate-induced occlusal position (BPOP as a muscular reference position should be evaluated in patients with TMD. Methods The BPOP was defined as the position at which a patient voluntarily closed his or her mouth while sitting in an upright posture after wearing an anterior flat bite plate for 5 minutes and then removing the plate. Twenty-one patients with TMDs underwent occlusal adjustment using the BPOP. The occlusal adjustments were continued until bilateral occlusal contacts were obtained in the BPOP. The treatment outcomes were evaluated using the subjective dysfunction index (SDI and the Helkimo Clinical Dysfunction Index (CDI before and after the occlusal adjustments; the changes in these two indices between the first examination and a one-year follow-up examination were then analyzed. In addition, the difference between the HOP and the BPOP was three-dimensionally measured before and after the treatment. Results The percentage of symptom-free patients after treatment was 86% according to the SDI and 76% according to the CDI. The changes in the two indices after treatment were significant (p 0.1. Conclusion Although the results of the present study should be confirmed in other studies, a randomized clinical trial examining occlusal adjustments using the BPOP as a reference position appears to be warranted.

Venous pump of the calf: a study of venous and muscular pressures.

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Alimi, Y S; Barthelemy, P; Juhan, C

1994-11-01

Little data are available concerning the relation between the muscular pumping mechanism and the variation of superficial and deep venous pressure during normal action of the calf pump; therefore we undertook this study to determine the pressure values in three compartments of the calf and in the deep and the superficial venous system and to establish correlation between muscular and venous pressure. Nine healthy young women with a mean age of 23 years (range 19 to 28 years) were examined. In the same calf, a muscular catheter was placed in the deep posterior compartment (DPC), in the superficial posterior compartment (SPC), and in the anterior tibial compartment (ATC), and a vascular catheter was placed in the popliteal vein and in the greater saphenous vein (GSV). The five lines of pressure were simultaneously recorded in the following situations: at rest, during Valsalva maneuver, foot flexion, and foot extension. The situation was studied with the patient in the following positions: decubitus, sitting, standing, and squatting. A final continuous recording was carried out after the patient had been walking for 5 minutes. Mean values with standard errors of muscular and venous pressure were established in each situation. At rest and during Valsalva maneuver, the muscular pressures did not vary, whereas venous pressures increased significantly when the patient was sitting and standing. On the other hand, squatting was associated with a rise in the muscular and vein pressures. Foot flexion entailed a significant increase in the ATC pressure and a rise in the GSV pressure, whereas foot extension caused the DPC pressure to rise without venous pressure modifications. Walking was associated with an alternating increase in the DPC, SPC, GSV and popliteal vein pressures when the foot was compressed to floor followed by a significant decrease when the foot pressure was released. The variations in the deep and superficial venous pressures when the patient is sitting and

Combining central venous-to-arterial partial pressure of carbon dioxide difference and central venous oxygen saturation to guide resuscitation in septic shock.

Science.gov (United States)

Du, Wei; Liu, Da-Wei; Wang, Xiao-Ting; Long, Yun; Chai, Wen-Zhao; Zhou, Xiang; Rui, Xi

2013-12-01

Central venous oxygen saturation (Scvo2) is a useful therapeutic target when treating septic shock. We hypothesized that combining Scvo2 and central venous-to-arterial partial pressure of carbon dioxide difference (△Pco2) may provide additional information about survival. We performed a retrospective analysis of 172 patients treated for septic shock. All patients were treated using goal-directed therapy to achieve Scvo2 ≥ 70%. After 6 hours of treatment, we divided patients into 4 groups based on Scvo2 (<70% or ≥ 70%) and △Pco2 (<6 mm Hg or ≥ 6 mm Hg). Overall, 28-day mortality was 35.5%. For patients in whom the Scvo2 target was not achieved at 6 hours, mortality was 50.0%, compared with 29.5% in those in whom Scvo2 exceeded 70% (P = .009). In patients with Scvo2 ≥ 70%, mortality was lower if △Pco2 was <6 mm Hg than if △Pco2 was ≥ 6 mm Hg (56.1% vs 16.1%, respectively; P < .001) and 6-hour lactate clearance was superior (0.01 ± 0.61 vs 0.21 ± 0.31, respectively; P = .016). The combination of Scvo2 and △Pco2 appears to predict outcome in critically ill patients resuscitated from septic shock better than Scvo2 alone. Patients who meet both targets appear to clear lactate more efficiently. © 2013.

Evaluation of hepatic venous pulsatility and portal venous velocity with doppler ultrasonography during the puerperium

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Pekindil, Goekhan [Department of Radiology, Trakya University School of Medicine, 22030 Edirne (Turkey); Varol, Fuesun G. [Department of Obstetrics and Gynecology, Trakya University School of Medicine, 22030 Edirne (Turkey); Ali Yuece, M. [Department of Obstetrics and Gynecology, Trakya University School of Medicine, 22030 Edirne (Turkey); Yardim, Turgut [Department of Obstetrics and Gynecology, Trakya University School of Medicine, 22030 Edirne (Turkey)

1999-03-01

Objective: The aim of this study is to evaluate pregnancy-induced changes of hepatic venous pulsatility and portal venous velocity in the puerperium and to determine if these changes disappeared by the end of the puerperium. Methods and material: Healthy normal volunteers (90) were examined on the 2nd and 7th days of puerperium and between the 6th and 8th weeks postpartum. Doppler waveform patterns were obtained in the middle hepatic vein and main portal vein. The hepatic venous pulsatility was named as normal, damped or flat. Results: On the 2nd day postpartum, the hepatic vein pulsatility was shown as normal in 8 (26%), damped in 11 (37%) and flat in 11 (37%) cases. On the 7th day postpartum, 15 (50%) cases had normal, 9 (30%) cases had dampened, and 6 (20%) cases had still flat pattern. The majority of the cases (60%) displayed normal hepatic venous pulsatility in the 6th and 8th weeks of puerperium, whereas 23% had still dampened and 17% had flat patterns. There was a trend toward normal pulsatility with increasing puerperal age. The mean portal venous velocity was still higher than the non-pregnant levels and did not showed significant alterations during puerperium. Conclusion: This study emphasised that, since pregnancy-induced alterations in hepatic venous pulsatility and portal venous velocity had not completely returned to normal in most cases until the end of the puerperium, these physiological changes should be considered whenever hepatic and portal systems are interpreted with Doppler sonography during the puerperal period.

Evaluation of hepatic venous pulsatility and portal venous velocity with doppler ultrasonography during the puerperium

International Nuclear Information System (INIS)

Pekindil, Goekhan; Varol, Fuesun G.; Ali Yuece, M.; Yardim, Turgut

1999-01-01

Objective: The aim of this study is to evaluate pregnancy-induced changes of hepatic venous pulsatility and portal venous velocity in the puerperium and to determine if these changes disappeared by the end of the puerperium. Methods and material: Healthy normal volunteers (90) were examined on the 2nd and 7th days of puerperium and between the 6th and 8th weeks postpartum. Doppler waveform patterns were obtained in the middle hepatic vein and main portal vein. The hepatic venous pulsatility was named as normal, damped or flat. Results: On the 2nd day postpartum, the hepatic vein pulsatility was shown as normal in 8 (26%), damped in 11 (37%) and flat in 11 (37%) cases. On the 7th day postpartum, 15 (50%) cases had normal, 9 (30%) cases had dampened, and 6 (20%) cases had still flat pattern. The majority of the cases (60%) displayed normal hepatic venous pulsatility in the 6th and 8th weeks of puerperium, whereas 23% had still dampened and 17% had flat patterns. There was a trend toward normal pulsatility with increasing puerperal age. The mean portal venous velocity was still higher than the non-pregnant levels and did not showed significant alterations during puerperium. Conclusion: This study emphasised that, since pregnancy-induced alterations in hepatic venous pulsatility and portal venous velocity had not completely returned to normal in most cases until the end of the puerperium, these physiological changes should be considered whenever hepatic and portal systems are interpreted with Doppler sonography during the puerperal period

Increased release of norepinephrine and dopamine from canine kidney during bilateral carotid occlusion

International Nuclear Information System (INIS)

Bradley, T.; Hjemdahl, P.; DiBona, G.F.

1987-01-01

The renal overflow of norepinephrine (NE) and dopamine (DA) to plasma from the innervated kidney was studied at rest and during sympathetic nervous system activation by bilateral carotid artery occlusion (BCO) in vagotomized dogs under barbiturate or barbiturate/nitrous oxide anesthesia. BCO elevated arterial pressure and the arterial plasma concentration of NE, DA, and epinephrine (Epi). Renal vascular resistance (renal arterial pressure kept constant) increased by 15 +/- 7% and the net renal venous outflows (renal veno-arterial concentration difference x renal plasma flow) of NE and DA were enhanced. To obtain more correct estimates of the renal contribution to the renal venous catecholamine outflow, they corrected for the renal extraction of arterial catecholamines, assessed as the extractions of [ 3 H]NE, [ 3 H]DA, or endogenous Epi. The [ 3 H]NE corrected renal NE overflow to plasma increased from 144 +/- 40 to 243 +/- 64 pmol-min -1 during BCO, which, when compared with a previous study of the [ 3 H]NE corrected renal NE overflow to plasma evoked by electrical renal nerve stimulation, corresponds to a 40% increase in nerve impulse frequency from ∼ 0.6 Hz. If the renal catecholamine extraction was not taken into account the effect of BCO was underestimated. The renal DA overflow to plasma was about one-fifth of the NE overflow both at rest and during BCO, indicating that there was no preferential activation of noradrenergic or putative dopaminergic nerves by BCO

Positive correlation between occlusion rate and nidus size of proton beam treated brain arteriovenous malformations (AVMs)

DEFF Research Database (Denmark)

Blomquist, Erik; Ronne Engström, Elisabeth; Borota, Ljubisa

2016-01-01

symptoms, clinical course, the size of AVM nidus and rate of occlusion was collected. Outcome parameters were the occlusion of the AVM, clinical outcome and side effects.Results. The rate of total occlusion was overall 68%. For target volume 0-2cm3 it was 77%, for 3-10 cm3 80%, for 11-15 cm3 50% and for 16...... of these had no effect and the other only partial occlusion from proton beams. Two thirds of those presenting with seizures reported an improved seizure situation after treatment.Conclusion. Our observations agree with earlier results and show that proton beam irradiation is a treatment alternative for brain......Background. Proton beam radiotherapy of arteriovenous malformations (AVM) in the brain has been performed in Uppsala since 1991. An earlier study based on the first 26 patients concluded that proton beam can be used for treating large and medium sized AVMs that were considered difficult to treat...

Effect of glove occlusion on the skin barrier

DEFF Research Database (Denmark)

Tiedemann, Daniel; Clausen, Maja Lisa; John, Swen Malthe

2016-01-01

that the negative effect of occlusion in itself is limited, and that only extensive and long-term occlusion will cause barrier impairment. However, studies investigating combined effect of occlusion and exposure to soaps/detergents indicate that occlusion significantly enhances the skin barrier damage caused...... by detergents/soaps in a dose-response fashion....

A Novel Stretch Sensor to Measure Venous Hemodynamics

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Syrpailyne Wankhar

2018-07-01

Full Text Available Chronic venous insufficiency is a debilitating condition causing varicose veins and venous ulcers. The pathophysiology includes reflux and venous obstruction. The diagnosis is often made by clinical examination and confirmed by Venous Doppler studies. Plethysmography helps to quantitatively examine the reflux and diagnose the burden of deep venous pathology to better understand venous hemodynamics, which is not elicited by venous duplex examination alone. However, most of these tests are qualitative, expensive, and not easily available. In this paper, we demonstrate the potential use of a novel stretch sensor in the assessment of venous hemodynamics during different maneuvers by measuring the change in calf circumference. We designed the stretch sensor by using semiconductor strain gauges pasted onto a small metal bar to form a load cell. The elastic and Velcro material attached to the load cell form a belt. It converts the change in limb circumference to a proportional tension (force of distension when placed around the calf muscle. We recorded the change in limb circumference from arrays of stretch sensors by using an in-house data acquisition system. We calculated the venous volume (VV, venous filling index (VFI, ejection fraction (EF and residual venous volume (RVV on two normal subjects and on two patients to assess venous hemodynamics. The values (VV > 60 ml, VFI 60%, RVV 2ml/s, EF 35% in patients were comparable to those reported in the literature.

[High-frequency components of occlusal sound in sliding movement].

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Nagai, K

1990-03-01

We postulated that high-frequency components of the occlusal sound occurring due to the characteristic vibration of teeth can be useful data for confirmation of the stability in occlusion, and studied the high-frequency components in the cases both of an experimental sliding movement and a normal occlusion. The results obtained were as follows. 1. A study on high-frequency components of the occlusal sound in an experimental sliding movement. 1) A study on wave type of the occlusal sound revealed one damped oscillation in an impact form and two in a slide form. 2) Spectrum analysis of the damped oscillation showed a similar spectrum pattern with a peak existing between 16KHz or more and 17KHz or less in both impact and slide cases. 2. A study on high-frequency components of the occlusal sound in a normal occlusion case. 1) The wave type in occlusal sound we have observed in a normal occlusion group and in a prosthetic or operative group was as follows: One damped oscillation shown in an impact form and two damped oscillation in a slide form which were the same as those shown in the case where an interference device was attached. 2) Duration of the sliding movement was short in a normal occlusion group, but was prolonged in a prosthetic or operative group. 3) The incidence of the wave type in occlusal sound was 56.7% in a prosthetic or operative group as compared to 87.8% in a normal occlusion group in an impact form. In contrast, the incidence was 43.3% in a prosthetic or operative group as compared to 12.2% in a normal occlusion group in a slide form. Such difference in the incidence between the wave types suggested that high-frequency components of occlusal sound can be an index for judgement of the stability in occlusion.

A Predictive Framework to Elucidate Venous Stenosis: CFD & Shape Optimization.

Science.gov (United States)

Javid Mahmoudzadeh Akherat, S M; Cassel, Kevin; Boghosian, Michael; Hammes, Mary; Coe, Fredric

2017-07-01

The surgical creation of vascular accesses for renal failure patients provides an abnormally high flow rate conduit in the patient's upper arm vasculature that facilitates the hemodialysis treatment. These vascular accesses, however, are very often associated with complications that lead to access failure and thrombotic incidents, mainly due to excessive neointimal hyperplasia (NH) and subsequently stenosis. Development of a framework to monitor and predict the evolution of the venous system post access creation can greatly contribute to maintaining access patency. Computational fluid dynamics (CFD) has been exploited to inspect the non-homeostatic wall shear stress (WSS) distribution that is speculated to trigger NH in the patient cohort under investigation. Thereafter, CFD in liaison with a gradient-free shape optimization method has been employed to analyze the deformation modes of the venous system enduring non-physiological hemodynamics. It is observed that the optimally evolved shapes and their corresponding hemodynamics strive to restore the homeostatic state of the venous system to a normal, pre-surgery condition. It is concluded that a CFD-shape optimization coupling that seeks to regulate the WSS back to a well-defined physiological WSS target range can accurately predict the mode of patient-specific access failure.

Stent Graft in Managing Juxta-Renal Aortoiliac Occlusion

International Nuclear Information System (INIS)

Prabhudesai, V.; Mitra, K.; West, D. J.; Dean, M. R. E.

2003-01-01

Endovascular procedures are frequently used as an alternative to surgical bypass in aortic and iliac occlusion. Stents have revolutionized the scope of such endovascular procedures, but there are few reports of stents or stent grafts in occlusive juxta-renal aortic occlusion. We present a case where such occlusion was managed by use of a stent graft with successful outcome

The unsuitability of implantable Doppler probes for the early detection of renal vascular complications - a porcine model for prevention of renal transplant loss

DEFF Research Database (Denmark)

Amdisen, Chris; Jespersen, Bente; Møldrup, Ulla

2017-01-01

Abstract Background: Vascular occlusion is a rare, but serious complication after kidney transplantation often resulting in graft loss. We therefore aimed to develop an experimental porcine model for stepwise reduction of the renal venous blood flow and to compare an implantable Doppler probe...... and microdialysis for fast detection of vascular occlusion. Methods: In 20 pigs, implantable Doppler probes were placed on the renal artery and vein and a microdialysis catheter was placed in the renal cortex. An arterial flowprobe served as gold standard. Following two-hour baseline measurements, the pigs were....../3 (66%) reduction in renal blood flow. The implantable Doppler probe was not able to detect flow changes until there was total venous occlusion. Microdialysis detected changes in local metabolism after both arterial and venous occlusion; the implantable Doppler probe could only detect vascular...

Endovascular Treatment Strategies in Aortoiliac Occlusion

International Nuclear Information System (INIS)

Ozkan, Ugur; Oguzkurt, Levent; Tercan, Fahri; Gumus, Burcak

2009-01-01

The aim of this study was to report our experience in endovascular treatment of total aortoiliac occlusion. Five patients who underwent endovascular recanalization procedures including manual aspiration thrombectomy, balloon angioplasty, and stent placement for total aortoiliac occlusion in a 4-year period were reviewed retrospectively. The mean age of patients was 51 years (range, 43 to 58 years). All patients had abdominal aorta and bilateral common iliac artery occlusion with or without external iliac artery occlusion. All patients either had a contraindication to surgery or refused it. Initial technical success was obtained in four of five (80%) patients. Endovascular techniques were successful in four patients who had good distal runoff and short-segment aortoiliac occlusion, but failed in a patient who had the worst distal runoff and long-segment aortoiliac occlusion. We observed two major complications, one of which was bilateral rupture of the common iliac arteries treated with covered stent placement. Another patient had extension of intra-aortic thrombus into the iliac stent after primary stenting. This was successfully treated with manual aspiration thrombectomy. Aortic and iliac stents remained patent during the follow-up period (median, 18 months; range, 3 to 26 months) in four patients. Primary patency rates at 6, 12, and 24 months were all 80%. In conclusion, endovascular treatment can be an alternative for aortoiliac occlusion in selected patients. Short- to midterm follow-up so far is satisfactory. Removal of intra-aortic thrombus with manual aspiration thrombectomy before balloon angioplasty and/or stenting is possible and a good alternative to thrombolysis.

Effects of parasagittal meningiomas on intracranial venous circulation assessed by the virtual reality technology.

Science.gov (United States)

Wang, Shousen; Ying, Jianbin; Wei, Liangfeng; Li, Shiqing; Jing, Junjie

2015-01-01

This study is to investigate the compensatory intracranial venous pathways in parasagittal meningiomas (PSM) patients by virtual reality technology. A total of 48 PSM patients (tumor group) and 20 patients with trigeminal neuralgia and hemifacial spasm but without intracranial venous diseases (control group) were enrolled. All patients underwent 3D CE-MRV examination. The 3D reconstructed images by virtual reality technology were used for assessment of diameter and number of intracranial veins, tumor location, venous sinus invasion degree and collateral circulation formation. Diameter of bridging veins in posterior 1/3 superior sagittal sinus (SSS) in tumor group was significantly smaller than that of the control group (P < 0.05). For tumors located in mid 1/3 SSS, diameter of bridging veins and vein of Labbé (VL) in posterior 1/3 SSS decreased significantly (P < 0.05). For tumors located in posterior 1/3 SSS, bridging vein number and transverse sinus (TS) diameter significantly decreased while superficial Sylvian vein (SSV) diameter increased significantly (P < 0.05). Compared with tumor in posterior 1/3 SSS subgroup, number of bridging veins in the tumor in mid 1/3 SSS subgroup increased significantly (P < 0.05). Compared with control group, only the bridging vein number in anterior 1/3 SSS segment in invasion Type 3-4 tumor subgroup decreased significantly (P < 0.05). Diameter of TS and bridging veins in posterior 1/3 SSS segment in sinus invasion Type 5-6 tumor subgroup decreased significantly (P < 0.05). Compared with control group, only the diameter of VL and TS of collateral circulation Grade 1 tumor subgroup decreased significantly (P < 0.05) while in Grade 3 tumor subgroup, TS diameter decreased and SSV diameter increased significantly (P < 0.05). The intracranial blood flow is mainly drained through SSV drainage after SSS occlusion by PSM.

Current concepts in repair of extremity venous injury.

Science.gov (United States)

Williams, Timothy K; Clouse, W Darrin

2016-04-01

Extremity venous injury management remains controversial. The purpose of this communication is to offer perspective as well as experiential and technical insight into extremity venous injury repair. Available literature is reviewed and discussed. Historical context is provided. Indication, the decision process for repair, including technical conduct, is delineated. In particular, the authors' experiences in both civilian and wartime injury are used for perspective. Extremity venous injury repair was championed within data from the Vietnam Vascular Registry. However, patterns of extremity venous injury differ between combat and civilian settings. Since Vietnam, civilian descriptive series opine the benefits and potential complications associated with both venous injury repair and ligation. These surround extremity edema, chronic venous insufficiency, thromboembolism, and limb loss. Whereas no clear superiority in either approach has been identified to date, there appears to be no increased risk of pulmonary embolism or chronic venous changes with repair. Newer data from the wars in Iraq and Afghanistan and meta-analysis have reinforced this and also have suggested limb salvage benefit for extremity venous repair in combined arterial and venous injuries in modern settings. The patient's physiologic state and associated injury drive five triage categories suggesting vein injury management. Vein repair thrombosis occurs in a significant proportion, yet many recanalize and possibly have a positive impact on limb venous return. Further, early decompression favors reduced blood loss, acute edema, and inflammation, supporting collateral development. Large soft tissue injury minimizing collateral capacity increases the importance of repair. Constructs of repair are varied with modest differences in patency. Venous shunting is feasible, but specific roles remain nebulous. An aggressive posture toward extremity venous injury repair seems justified today because of the likely

Percutaneous Endovascular Salvage Techniques for Implanted Venous Access Device Dysfunction

International Nuclear Information System (INIS)

Breault, Stéphane; Glauser, Frédéric; Babaker, Malik; Doenz, Francesco; Qanadli, Salah Dine

2015-01-01

PurposeImplanted venous access devices (IVADs) are often used in patients who require long-term intravenous drug administration. The most common causes of device dysfunction include occlusion by fibrin sheath and/or catheter adherence to the vessel wall. We present percutaneous endovascular salvage techniques to restore function in occluded catheters. The aim of this study was to evaluate the feasibility, safety, and efficacy of these techniques.Methods and MaterialsThrough a femoral or brachial venous access, a snare is used to remove fibrin sheath around the IVAD catheter tip. If device dysfunction is caused by catheter adherences to the vessel wall, a new “mechanical adhesiolysis” maneuver was performed. IVAD salvage procedures performed between 2005 and 2013 were analyzed. Data included clinical background, catheter tip position, success rate, recurrence, and rate of complication.ResultsEighty-eight salvage procedures were performed in 80 patients, mostly women (52.5 %), with a mean age of 54 years. Only a minority (17.5 %) of evaluated catheters were located at an optimal position (i.e., cavoatrial junction ±1 cm). Mechanical adhesiolysis or other additional maneuvers were used in 21 cases (24 %). Overall technical success rate was 93.2 %. Malposition and/or vessel wall adherences were the main cause of technical failure. No complications were noted.ConclusionThese IVAD salvage techniques are safe and efficient. When a catheter is adherent to the vessel wall, mechanical adhesiolysis maneuvers allow catheter mobilization and a greater success rate with no additional risk. In patients who still require long-term use of their IVAD, these procedures can be performed safely to avoid catheter replacement

Percutaneous Endovascular Salvage Techniques for Implanted Venous Access Device Dysfunction

Energy Technology Data Exchange (ETDEWEB)

Breault, Stéphane, E-mail: stephane.breault@chuv.ch [Lausanne University Hospital, Diagnostic and Interventional Radiology Department (Switzerland); Glauser, Frédéric, E-mail: frederic.glauser@chuv.ch [Lausanne University Hospital, Angiology and Diagnostic and Interventional Radiology Departments (Switzerland); Babaker, Malik, E-mail: malik.babaker@chuv.ch; Doenz, Francesco, E-mail: francesco.doenz@chuv.ch; Qanadli, Salah Dine, E-mail: salah.qanadli@chuv.ch [Lausanne University Hospital, Diagnostic and Interventional Radiology Department (Switzerland)

2015-06-15

PurposeImplanted venous access devices (IVADs) are often used in patients who require long-term intravenous drug administration. The most common causes of device dysfunction include occlusion by fibrin sheath and/or catheter adherence to the vessel wall. We present percutaneous endovascular salvage techniques to restore function in occluded catheters. The aim of this study was to evaluate the feasibility, safety, and efficacy of these techniques.Methods and MaterialsThrough a femoral or brachial venous access, a snare is used to remove fibrin sheath around the IVAD catheter tip. If device dysfunction is caused by catheter adherences to the vessel wall, a new “mechanical adhesiolysis” maneuver was performed. IVAD salvage procedures performed between 2005 and 2013 were analyzed. Data included clinical background, catheter tip position, success rate, recurrence, and rate of complication.ResultsEighty-eight salvage procedures were performed in 80 patients, mostly women (52.5 %), with a mean age of 54 years. Only a minority (17.5 %) of evaluated catheters were located at an optimal position (i.e., cavoatrial junction ±1 cm). Mechanical adhesiolysis or other additional maneuvers were used in 21 cases (24 %). Overall technical success rate was 93.2 %. Malposition and/or vessel wall adherences were the main cause of technical failure. No complications were noted.ConclusionThese IVAD salvage techniques are safe and efficient. When a catheter is adherent to the vessel wall, mechanical adhesiolysis maneuvers allow catheter mobilization and a greater success rate with no additional risk. In patients who still require long-term use of their IVAD, these procedures can be performed safely to avoid catheter replacement.

Spreading depression and focal venous cerebral ischemia enhance cortical neurogenesis

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Ryo Tamaki

2017-01-01

Full Text Available Endogenous neurogenesis can arise from a variety of physiological stimuli including exercise, learning, or “enriched environment” as well as pathological conditions such as ischemia, epilepsy or cortical spreading depression. Whether all these conditions use a common trigger to set off endogenous neurogenesis is yet unclear. We hypothesized that cortical spreading depression (CSD induces neurogenesis in the cerebral cortex and dentate gyrus after cerebral venous ischemia. Forty-two Wistar rats alternatively underwent sham operation (Sham, induction of ten CSDs or venous ischemia provoked via occlusion of two adjacent superficial cortical vein followed by ten induced CSDs (CSD + 2-VO. As an additional control, 15 naïve rats received no intervention except 5-bromo-2′-deoxyuridine (BrdU treatment for 7 days. Sagittal brain slices (40 μm thick were co-stained for BrdU and doublecortin (DCX; new immature neuronal cells on day 9 or NeuN (new mature neuronal cells on day 28. On day 9 after sham operation, cell proliferation and neurogenesis occurred in the cortex in rats. The sole induction of CSD had no effect. But on days 9 and 28, more proliferating cells and newly formed neurons in the ipsilateral cortex were observed in rats subjected to CSD + 2VO than in rats subjected to sham operation. On days 9 and 28, cell proliferation and neurogenesis in the ipsilateral dentate gyrus was increased in sham-operated rats than in naïve rats. Our data supports the hypothesis that induced cortical neurogenesis after CSD + 2-VO is a direct effect of ischemia, rather than of CSD alone.

Neuromuscular dentistry: Occlusal diseases and posture.

Science.gov (United States)

Khan, Mohd Toseef; Verma, Sanjeev Kumar; Maheshwari, Sandhya; Zahid, Syed Naved; Chaudhary, Prabhat K

2013-01-01

Neuromuscular dentistry has been a controversial topic in the field of dentistry and still remains debatable. The issue of good occlusion and sound health has been repeatedly discussed. Sometimes we get complains of sensitive teeth and sometimes of tired facial muscles on getting up in the morning. Owing to the intimate relation of masticatory apparatus with the cranium and cervico-scapular muscular system, the disorders in any system, draw attention from concerned clinicians involved in management, to develop an integrated treatment protocol for the suffering patients. There may be patients reporting to the dental clinics after an occlusal restoration or extraction, having pain in or around the temporomandibular joint, headache or neck pain. Although their esthetic demands must not be undermined during the course of treatment plan, whenever dental treatment of any sort is planned, occlusion/bite should be given prime importance. Very few dentist are able to diagnose the occlusal disease and of those who diagnose many people resort to aggressive treatment modalities. This paper aims to report the signs of occlusal disease, and discuss their association with TMDs and posture.

Cerebral venous thrombosis

International Nuclear Information System (INIS)

Soralova, T.; Sevcikova, H.; Petersky, D.

2014-01-01

We decided to process this theme due to its nonspecific clinical features as they often cause diagnostic problems not only to clinicians but also to diagnostic. It is important to think of this disease mainly in young women who administer hormonal contraception. Imaging methods play the crucial role in diagnostic of cerebral venous sinus thrombosis. The gold standard is a native CT of brain which shows the venous sinus thrombosis as a hyperdense lesion in the locus of the sinus (dense triangle sign), CT venography shows the sinus thrombosis as a defect in a contrast filling of the venous sinus (empty delta sign). Other investigative methods are magnetic resonance imaging or MRA. In short we also mention quite a rare but more serious thrombosis of profound cerebral veins v. cerebri magna-Galeni, vv. cerebri internae). The importance of early diagnostic and non specificity of symptoms is presented in 3 clinical cases that are the part of this work. (author)

Epulis and pyogenic granuloma with occlusal interference

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Widowati Witjaksono

2005-06-01

Full Text Available In dental clinic of Hospital University Science Malaysia (HUSM, there were cases with Localized Gingival Enlargement (LGE in the oral cavity with occlusal interference. In this study, three cases were observed. They were a 13 - year- old female with fibrous lge around 31 and 32 with occlusal interference in protrusive movement due to X bite, a 15 - year – old female with pyogenic granuloma near 11 & 21 with occlusal interference due to deep bite; and a 24 – year – old female who was eight months in pregnancy with pyogenic granuloma on the 34-35 and severe generalized pregnancy gingivitis with occlusal interference in centric occlusion and lateral movement. Clinical and histopathological diagnosis of the first case showed fibrous epulis, whereas the second and third cases disclosed pyogenic granuloma. Chronic trauma of the gingiva due to occlusal interference was assumed to be the cause of those LGE in case 1 and 2, while in case 3 poor oral hygiene and chronic trauma were assumed to be the etiologic factors.

Thermographic venous blood flow characterization with external cooling stimulation

Science.gov (United States)

Saxena, Ashish; Ng, E. Y. K.; Raman, Vignesh

2018-05-01

Experimental characterization of blood flow in a human forearm is done with the application of continuous external cooling based active thermography method. Qualitative and quantitative detection of the blood vessel in a thermal image is done, along with the evaluation of blood vessel diameter, blood flow direction, and velocity in the target blood vessel. Subtraction based image manipulation is performed to enhance the feature contrast of the thermal image acquired after the removal of external cooling. To demonstrate the effect of occlusion diseases (obstruction), an external cuff based occlusion is applied after the removal of cooling and its effect on the skin rewarming is studied. Using external cooling, a transit time method based blood flow velocity estimation is done. From the results obtained, it is evident that an external cooling based active thermography method can be used to develop a diagnosis tool for superficial blood vessel diseases.

Estimation of Absorbed Dose in Occlusal Radiography

International Nuclear Information System (INIS)

Yoo, Young Ah; Choi, Karp Shick; Lee, Sang Han

1990-01-01

The purpose of this study was to estimate absorbed dose of each important anatomic site of phantom (RT-210 Head and Neck Section R, Humanoid Systems Co., U.S.A.) head in occlusal radiography. X-radiation dosimetry at 12 anatomic sites in maxillary anterior topography, maxillary posterior topography, mandibular anterior cross-section, mandibular posterior cross-section, mandibular anterior topographic, mandibular posterior topographic occlusal projection was performed with calcium sulfate thermoluminescent dosimeters under 70 Kvp and 15 mA, 1/4 second (8 inch cone ) and 1 second (16 inch cone) exposure time. The results obtained were as follows: Skin surface produced highest absorbed dose ranged between 3264 mrad and 4073 mrad but there was little difference between projections. In maxillary anterior topographic occlusal radiography, eyeballs, maxillary sinuses, and pituitary gland sites produced higher absorbed doses than those of other sites. In maxillary posterior topographic occlusal radiography, exposed eyeball site and exposed maxillary sinus site produced high absorbed doses. In mandibular anterior cross-sectional occlusal radiography, all sites were produced relatively low absorbed dose except eyeball sites. In Mandibular posterior cross-sectional occlusal radiography, exposed eyeball site and exposed maxillary sinus site were produced relatively higher absorbed doses than other sites. In mandibular anterior topographic occlusal radiography, maxillary sinuses, submandibular glands, and thyroid gland sites produced high absorbed doses than other sites. In mandibular posterior topographic occlusal radiography, submandibular gland site of the exposed side produced high absorbed dose than other sites and eyeball site of the opposite side produced relatively high absorbed dose.

Combined surface and volumetric occlusion shading

KAUST Repository

Schott, Matthias O.; Martin, Tobias; Grosset, A. V Pascal; Brownlee, Carson; Hollt, Thomas; Brown, Benjamin P.; Smith, Sean T.; Hansen, Charles D.

2012-01-01

In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

Combined surface and volumetric occlusion shading

KAUST Repository

Schott, Matthias O.

2012-02-01

In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

Mid-Term Outcomes of Endovascular Treatment for TASC-II D Femoropopliteal Occlusive Disease with Critical Limb Ischemia

Energy Technology Data Exchange (ETDEWEB)

Torres-Blanco, Álvaro, E-mail: atorres658@yahoo.es; Edo-Fleta, Gemma; Gómez-Palonés, Francisco; Molina-Nácher, Vicente; Ortiz-Monzón, Eduardo [Hospital Universitario Dr. Peset, Department of Angiology, Endovascular and Vascular Surgery (Spain)

2016-03-15

PurposeThe purpose of the study was to assess the safety and midterm effectiveness of endovascular treatment in Trans-Atlantic Inter-Society Consensus II (TASC-II) D femoropopliteal occlusions in patients with critical limb ischemia (CLI).MethodsPatients with CLI who underwent endovascular treatment for TASC-D de novo femoropopliteal occlusive disease between September 2008 and December 2013 were selected. Data included anatomic features, pre- and postprocedure ankle-brachial index, duplex ultrasound, and periprocedural complications. Sustained clinical improvement, limb salvage rate, freedom from target lesion revascularization (TLR), and freedom from target extremity revascularization (TER) were assessed by Kaplan–Meier estimation and predictors of restenosis/occlusion with Cox analysis.ResultsThirty-two patients underwent treatment of 35 TASC-D occlusions. Mean age was 76 ± 9. Mean lesion length was 23 ± 5 cm. Twenty-eight limbs (80 %) presented tissue loss. Seventeen limbs underwent treatment by stent, 13 by stent-graft, and 5 by angioplasty. Mean follow-up was 29 ± 20 months. Seven patients required major amputation and six patients died during follow-up. Eighteen endovascular and three surgical TLR procedures were performed due to restenosis or occlusion. Estimated freedom from TLR and TER rates at 2 years were 41 and 76 %, whereas estimated primary and secondary patency rates were 41 and 79 %, respectively.ConclusionsEndovascular treatment for TASC II D lesions is safe and offers satisfying outcomes. This patient subset would benefit from a minimally invasive approach. Follow-up is advisable due to a high rate of restenosis. Further follow-up is necessary to know the long-term efficacy of these procedures.

Human cerebral venous outflow pathway depends on posture and central venous pressure

Science.gov (United States)

Gisolf, J; van Lieshout, J J; van Heusden, K; Pott, F; Stok, W J; Karemaker, J M

2004-01-01

Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture and central venous pressure (CVP) on the distribution of cerebral outflow over the internal jugular veins and the vertebral plexus, using a mathematical model. Input to the model was a data set of beat-to-beat cerebral blood flow velocity and CVP measurements in 10 healthy subjects, during baseline rest and a Valsalva manoeuvre in the supine and standing position. The model, consisting of 2 jugular veins, each a chain of 10 units containing nonlinear resistances and capacitors, and a vertebral plexus containing a resistance, showed blood flow mainly through the internal jugular veins in the supine position, but mainly through the vertebral plexus in the upright position. A Valsalva manoeuvre while standing completely re-opened the jugular veins. Results of ultrasound imaging of the right internal jugular vein cross-sectional area at the level of the laryngeal prominence in six healthy subjects, before and during a Valsalva manoeuvre in both body positions, correlate highly with model simulation of the jugular cross-sectional area (R2 = 0.97). The results suggest that the cerebral venous flow distribution depends on posture and CVP: in supine humans the internal jugular veins are the primary pathway. The internal jugular veins are collapsed in the standing position and blood is shunted to an alternative venous pathway, but a marked increase in CVP while standing completely re-opens the jugular veins. PMID:15284348

Cerebral venous outflow and cerebrospinal fluid dynamics

Directory of Open Access Journals (Sweden)

Clive B. Beggs

2014-12-01

Full Text Available In this review, the impact of restricted cerebral venous outflow on the biomechanics of the intracranial fluid system is investigated. The cerebral venous drainage system is often viewed simply as a series of collecting vessels channeling blood back to the heart. However there is growing evidence that it plays an important role in regulating the intracranial fluid system. In particular, there appears to be a link between increased cerebrospinal fluid (CSF pulsatility in the Aqueduct of Sylvius and constricted venous outflow. Constricted venous outflow also appears to inhibit absorption of CSF into the superior sagittal sinus. The compliance of the cortical bridging veins appears to be critical to the behaviour of the intracranial fluid system, with abnormalities at this location implicated in normal pressure hydrocephalus. The compliance associated with these vessels appears to be functional in nature and dependent on the free egress of blood out of the cranium via the extracranial venous drainage pathways. Because constricted venous outflow appears to be linked with increased aqueductal CSF pulsatility, it suggests that inhibited venous blood outflow may be altering the compliance of the cortical bridging veins.

Biomechanics of occlusion--implications for oral rehabilitation.

Science.gov (United States)

Peck, C C

2016-03-01

The dental occlusion is an important aspect of clinical dentistry; there are diverse functional demands ranging from highly precise tooth contacts to large crushing forces. Further, there are dogmatic, passionate and often diverging views on the relationship between the dental occlusion and various diseases and disorders including temporomandibular disorders, non-carious cervical lesions and tooth movement. This study provides an overview of the biomechanics of the masticatory system in the context of the dental occlusion's role in function. It explores the adaptation and precision of dental occlusion, its role in bite force, jaw movement, masticatory performance and its influence on the oro-facial musculoskeletal system. Biomechanics helps us better understand the structure and function of biological systems and consequently an understanding of the forces on, and displacements of, the dental occlusion. Biomechanics provides insight into the relationships between the dentition, jaws, temporomandibular joints, and muscles. Direct measurements of tooth contacts and forces are difficult, and biomechanical models have been developed to better understand the relationship between the occlusion and function. Importantly, biomechanical research will provide knowledge to help correct clinical misperceptions and inform better patient care. The masticatory system demonstrates a remarkable ability to adapt to a changing biomechanical environment and changes to the dental occlusion or other components of the musculoskeletal system tend to be well tolerated. © 2015 John Wiley & Sons Ltd.

Dental occlusion and temporomandibular disorders.

Science.gov (United States)

Stone, J Caitlin; Hannah, Andrew; Nagar, Nathan

2017-10-27

Data sourcesMedline, Scopus and Google Scholar.Study selectionTwo reviewers selected studies independently. English language clinical studies assessing the association between temporomandibular disorders (TMD) and features of dental occlusion were considered.Data extraction and synthesisStudy quality was assessed based on the Newcastle-Ottawa Scale (NOS) and a narrative synthesis was presented.ResultsIn all 25 studies (17 case-control, eight comparative) were included. Overall there was a high variability between occlusal features and TMD diagnosis. Findings were consistent with a lack of clinically relevant association between TMD and dental occlusion. Only two studies were associated with TMD in the majority (≥50%) of single variable analyses in patient populations. Only mediotrusive interferences are associated with TMD in the majority of multiple variable analyses.ConclusionsThe findings support the absence of a disease-specific association, there is no ground to hypothesise a major role for dental occlusion in the pathophysiology of TMDs. Dental clinicians are thus encouraged to move forward and abandon the old-fashioned gnathological paradig.

Parenchymal abnormalities in cerebral venous thrombosis: findings of magnetic resonance imaging and magnetic resonance angiography; Alteracoes parenquimatosas na trombose venosa cerebral: aspectos da ressonancia magnetica e da angiorressonancia

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Ferreira, Clecia Santos; Pellini, Marcos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia]. E-mail: csferreira@superig.com.br; Boasquevisque, Edson [Universidade do Estado do Rio de Janeiro, (UERJ), RJ (Brazil). Faculdade de Medicina. Dept. de Patologia; Souza, Luis Alberto M. de [Hospital da Beneficencia Portuguesa do Rio de Janeiro, RJ (Brazil). Servico de Imagem. Setor de Ressonancia Magnetica

2006-09-15

Objective: to determine the frequency and localization of parenchymal abnormalities in cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography as well as their correlation with the territory and affected venous drainage. Materials and methods: retrospective analysis (1996 to 2004) of 21 patients (3 male and 18 female) age range between 3 and 82 years (mean 40 years, median 36 years) with clinical and radiological diagnosis of cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography in 2D PC, 3D PC and contrast-enhanced 3D TOF sequences. The statistical analysis was performed with the qui-square test. Four patients had follow-up exams and three patients underwent digital subtraction angiography. Results: main predisposing factors were: infection, use of oral contraceptives, hormone replacement therapy and collagenosis. Predominant symptoms included: focal deficit, headache, alteration of consciousness level and seizures. Most frequent parenchymal manifestations were: cortical/subcortical edema or infarct, venous congestion and collateral circulation, meningeal enhancement and thalamic and basal ganglia edema or infarct. Occlusion occurred mainly in superior sagittal, left transverse, left sigmoid and straight sinuses. Cavernous sinus and cortical veins thrombosis are uncommon events. Conclusion: cerebral venous thrombosis is an uncommon cause of stroke, with favorable prognosis because of its reversibility. Diagnosis is highly dependent on the radiologist capacity to recognize the presentations of this disease, principally in cases where the diagnosis is suggested by parenchymal abnormalities rather than necessarily by visualization of the thrombus itself. An accurate and rapid diagnosis allows an immediate treatment, reducing the morbidity and mortality rates. (author)

Chronic venous disease.

Science.gov (United States)

Wolinsky, Claire D; Waldorf, Heidi

2009-11-01

Identifying characteristic cutaneous findings is important in determining the appropriate management of certain venous diseases. The health care provider should be familiar with the classic description of patterns and distributions of skin manifestations, such as varicose veins, stasis dermatitis, palpable cord, petechiae, and telangiectasias. In addition to the gross appearance of the skin, a skin biopsy may help elucidate a diagnosis. General treatment and prevention of the underlying venous pathology is essential. Furthermore, specific management of skin findings should include therapy to ameliorate progression of disease and symptomatology when warranted.

Central Venous Access

International Nuclear Information System (INIS)

Ganeshan, Arul; Warakaulle, Dinuke R.; Uberoi, Raman

2007-01-01

Central venous access plays an important role in the management of an ever-increasing population of patients ranging from those that are critically ill to patients with difficult clinical access. Interventional radiologists are key in delivering this service and should be familiar with the wide range of techniques and catheters now available to them. A comprehensive description of these catheters with regard to indications, technical aspects of catheterization, success rates, and associated early and late complications, as well as a review of various published guidelines on central venous catheter insertion are given in this article

Radiologically-placed venous ports in children under venous anesthesia

International Nuclear Information System (INIS)

Jang, Joo Yeon; Jeon, Ung Bae; Choo, Ki Seok; Hwang, Jae Yeon; Kim, Yong Woo; Lee, Yun Jin; Nam, Sang Ool; Lim, Young Tak

2015-01-01

To evaluate the efficacy and safety of radiologic venous port placement in children under venous anesthesia. Between April 2009 and July 2011, 44 ports were implanted in 41 children (24 boys, 17 girls). The age of patients ranged from 9 months to 19 years (mean, 6.5 years) and their body weights ranged from 6.8 kg to 56.3 kg (mean, 23.2 kg). Right internal jugular vein access was used in 42 ports, right subclavian vein in 1, and left subclavian in 1. Durability and complications of port implantation were reviewed. The technical success rate was 100%. The catheter life was 10-661 days (mean 246 days). Two patients died during the follow-up period, 21 and 6 ports were removed at the end of treatment or as a result of complications, respectively. One port was removed and replaced by a Hickmann catheter. Three ports were explanted due to port-related sepsis, one due to a catheter kink, and two for unexplained fever or insertion site pain. The overall port-related infection was 3 cases (6.8%, 0.28/1000 catheter days). Venous port placement by interventional radiologists in children under intravenous sedation is relatively safe, with a high rate of technical success and low rate of complications.

Radiologically-placed venous ports in children under venous anesthesia

Energy Technology Data Exchange (ETDEWEB)

Jang, Joo Yeon; Jeon, Ung Bae; Choo, Ki Seok; Hwang, Jae Yeon; Kim, Yong Woo; Lee, Yun Jin; Nam, Sang Ool; Lim, Young Tak [Pusan National University School of Medicine, Yangsan (Korea, Republic of)

2015-02-15

To evaluate the efficacy and safety of radiologic venous port placement in children under venous anesthesia. Between April 2009 and July 2011, 44 ports were implanted in 41 children (24 boys, 17 girls). The age of patients ranged from 9 months to 19 years (mean, 6.5 years) and their body weights ranged from 6.8 kg to 56.3 kg (mean, 23.2 kg). Right internal jugular vein access was used in 42 ports, right subclavian vein in 1, and left subclavian in 1. Durability and complications of port implantation were reviewed. The technical success rate was 100%. The catheter life was 10-661 days (mean 246 days). Two patients died during the follow-up period, 21 and 6 ports were removed at the end of treatment or as a result of complications, respectively. One port was removed and replaced by a Hickmann catheter. Three ports were explanted due to port-related sepsis, one due to a catheter kink, and two for unexplained fever or insertion site pain. The overall port-related infection was 3 cases (6.8%, 0.28/1000 catheter days). Venous port placement by interventional radiologists in children under intravenous sedation is relatively safe, with a high rate of technical success and low rate of complications.

Venous thromboembolism and arterial complications.

Science.gov (United States)

Prandoni, Paolo; Piovella, Chiara; Pesavento, Raffaele

2012-04-01

An increasing body of evidence suggests the likelihood of a link between venous and arterial thrombosis. The two vascular complications share several risk factors, such as age, obesity, smoking, diabetes mellitus, blood hypertension, hypertriglyceridemia, and metabolic syndrome. Moreover, there are many examples of conditions accounting for both venous and arterial thrombosis, such as the antiphospholipid antibody syndrome, hyperhomocysteinemia, malignancies, infections, and the use of hormonal treatment. Finally, several recent studies have consistently shown that patients with venous thromboembolism are at a higher risk of arterial thrombotic complications than matched control individuals. We, therefore, speculate the two vascular complications are simultaneously triggered by biological stimuli responsible for activating coagulation and inflammatory pathways in both the arterial and the venous system. Future studies are needed to clarify the nature of this association, to assess its extent, and to evaluate its implications for clinical practice. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Venous trauma in the Lebanon War--2006.

Science.gov (United States)

Nitecki, Samy S; Karram, Tony; Hoffman, Aaron; Bass, Arie

2007-10-01

Reports on venous trauma are relatively sparse. Severe venous trauma is manifested by hemorrhage, not ischemia. Bleeding may be internal or external and rarely may lead to hypovolemic shock. Repair of major extremity veins has been a subject of controversy and the current teaching is to avoid venous repair in an unstable or multi-trauma patient. The aim of the current paper is to present our recent experience in major venous trauma during the Lebanon conflict, means of diagnosis and treatment in a level I trauma center. All cases of major venous trauma, either isolated or combined with arterial injury, admitted to the emergency room during the 33-day conflict were reviewed. Out of 511 wounded soldiers and civilians who were admitted to our service over this period, 12 (2.3%) sustained a penetrating venous injury either isolated (5) or combined with arterial injury (7). All injuries were secondary to high velocity penetrating missiles or from multiple pellets stored in long-range missiles. All injuries were accompanied by additional insult to soft tissue, bone and viscera. The mean injury severity score was 15. Severe external bleeding was the presenting symptom in three cases of isolated venous injury (jugular, popliteal and femoral). The diagnosis of a major venous injury was made by a CTA scan in five cases, angiography in one and during surgical exploration in six cases. All injured veins were repaired: three by venous interposition grafts, four by end to end anastomosis, three by lateral suture and two by endovascular techniques. None of the injuries was treated by ligation of a major named vein. Immediate postoperative course was uneventful in all patients and the 30-day follow-up (by clinical assessment and duplex scan) has demonstrated a patent repair with no evidence of thrombosis. Without contradicting the wisdom of ligating major veins in the setup of multi-trauma or an unstable patient, our experience indicates that a routine repair of venous trauma can

Occlusion classifiers for picture rate conversion

NARCIS (Netherlands)

Bartels, C.L.L.; Haan, de G.; Rabbani, Majid

2009-01-01

Occlusion detection is an essential ingredient in high quality picture rate up-conversion and view interpolation applications. Many integrated approaches to occlusion detection and classification have been proposed, particularly in the stereo literature. However, due to their high complexity and

Venous infraction of developmental venous anomaly: A case report with perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Kim, Jung Youn; Kim, Hye Jeong; Hyun, Su Jeong; Kim, Hee Yeong; Kim, Han Myun; Hwang, Ji Young; Hong, Hye Suk; Woo, Ji Young; Yang, Ik [Dept. of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Kim, Eun Soo [Dept. of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang (Korea, Republic of)

2017-06-15

Developmental venous anomaly (DVA) is a common congenital venous malformation characterized by dilated medullary veins in caput medusa configuration and a draining vein. Despite the high incidence of DVAs, they are benign anatomic variations and rarely cause symptoms. Here, we report computed tomography and magnetic resonance imaging findings with perfusion images of acute infarction from underlying DVA in a 63-year-old female patient who presented with acute onset of neurologic symptoms and recovered without any neurologic deficit.

Human cerebral venous outflow pathway depends on posture and central venous pressure

DEFF Research Database (Denmark)

Gisolf, J; van Lieshout, J J; van Heusden, K

2004-01-01

and central venous pressure (CVP) on the distribution of cerebral outflow over the internal jugular veins and the vertebral plexus, using a mathematical model. Input to the model was a data set of beat-to-beat cerebral blood flow velocity and CVP measurements in 10 healthy subjects, during baseline rest......Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and a Valsalva manoeuvre in the supine and standing position. The model, consisting of 2 jugular veins, each a chain of 10 units containing nonlinear resistances and capacitors, and a vertebral plexus containing a resistance, showed blood flow mainly through the internal jugular veins in the supine position...

The occlusal imaging and analysis system by T-scan III in tinnitus patients.

Science.gov (United States)

Di Berardino, Federica; Filipponi, Eliana; Schiappadori, Massimo; Forti, Stella; Zanetti, Diego; Cesarani, Antonio

2016-04-01

Several studies have demonstrated that the prevalence of temporomandibular disorders (TMDs) in tinnitus patients ranges from 7% to 95%, and it is reported in literature that idiopathic tinnitus patients should be referred to a dentist to define whether or not the tinnitus is associated with TMD. However, the possible pathophysiological relation between TMDs and tinnitus is not generally investigated in clinical practice. The patterns and forces of occlusal contacts have been studied by means of T-scan III in 47 tinnitus patients (23 suffering from idiopathic tinnitus and 24 affected by Ménière disease [MD]) and 13 healthy subjects. The center of force target was offset in the opposite direction in 15/23 idiopathic tinnitus and in 7/24 MD patients (p = 0.026). No significant variation was found in the occlusal force. Our data suggest that a diagnostic screening method for occlusal stability in the intercuspidal position might be clinically useful in idiopathic tinnitus patients. Copyright © 2016 Chang Gung University. Published by Elsevier B.V. All rights reserved.

Temporal and spatiotemporal variability in comprehensive forearm skin microcirculation assessment during occlusion protocols.

Science.gov (United States)

Strömberg, Tomas; Sjöberg, Folke; Bergstrand, Sara

2017-09-01

Forearm skin hyperemia during release after brachial occlusion has been proposed for evaluating peripheral arterial disease and endothelial dysfunction. We used a novel fiberoptic system integrating Laser Doppler Flowmetry and Diffuse Reflectance Spectroscopy for a comprehensive pointwise model based microcirculation characterization. The aim was to evaluate and compare the temporal and the spatiotemporal variabilities in forearm skin microcirculation parameters (speed resolved perfusion; low speed 10mm/s, and total perfusion (Perf SR, tot ); the concentration and oxygenation of red blood cells, C RBC and S O2 ). Ten healthy subjects underwent arterial and venous forearm occlusions (AO, VO), repeated within one week. The repeatability was calculated as the coefficient of variation (CV) and the agreement as the intra-class correlation coefficient (ICC). The temporal CVs for conventional perfusion, Perf conv , Perf SR, tot , C RBC and S O2 were 14%, 12%, 9% and 9%, respectively, while the ICC were >0.75 (excellent). The perfusion measures generally had a higher spatiotemporal than temporal variability, which was not the case for S O2 and C RBC . The corresponding spatiotemporal CVs were 33%, 32%, 18% and 15%, respectively. During VO, C RBC had a CV0.40 (fair-good), and after release this was the case for C RBC (AO and VO), S O2 (VO) and Perf SR, fair-good agreement were: C RBC during and after release of VO, the Perf SR, value of these parameters in discriminating endothelial function remains to be studied. Copyright © 2017 Elsevier Inc. All rights reserved.

Chronic Venous Disease under pressure

NARCIS (Netherlands)

S.W.I. Reeder (Suzan)

2013-01-01

textabstractIn chapter 1 we provide a general introduction of this thesis. Chronic venous disease (CVD) is a common medical condition that affects 2-64% of the worldwide population and leads to leg ulcers in 1% of the Western population. Venous leg ulceration (VLU) has an unfavorable prognosis with

Percutaneous transfemoral repositioning of malpositioned central venous catheters.

Science.gov (United States)

Hartnell, G G; Roizental, M

1995-04-01

Central venous catheters inserted by blind surgical placement may not advance into a satisfactory position and may require repositioning. Malpositioning via surgical insertion is common in patients in whom central venous catheters have previously been placed, as these patients are more likely to have central venous thrombosis and distortion of central venous anatomy. This is less of a problem when catheter placement is guided by imaging; however, even when insertion is satisfactory, central venous catheters may become displaced spontaneously after insertion (Fig. 1). Repositioning can be effected by direct manipulation using guidewires or tip-deflecting wires [1, 2], by manipulation via a transfemoral venous approach [3-5], and by injection of contrast material or saline [6]. Limitations of the direct approach include (1) the number and type of maneuvers that can be performed to effect repositioning when anatomy is distorted, (2) difficulty in accessing the catheter, and (3) the risk of introducing infection. Moreover, these patients are often immunosuppressed, and there is a risk of introducing infection by exposing and directly manipulating the venous catheter. Vigorous injection of contrast material or saline may be unsuccessful for the same reasons: It seldom exerts sufficient force to reposition large-caliber central venous catheters and may cause vessel damage or rupture if injection is made into a small or thrombosed vessel. We illustrate several alternative methods for catheter repositioning via a transfemoral venous approach.

Surgical management of venous malformations.

Science.gov (United States)

Loose, D A

2007-01-01

Among vascular malformations, the predominantly venous malformations represent the majority of cases. They form a clinical entity and therefore need clear concepts concerning diagnosis and treatment. This paper presents an overview of contemporary classification as well as tactics and techniques of treatment. According to the Hamburg Classification, predominantly venous malformations are categorized into truncular and extratruncular forms, with truncular forms distinguished as obstructions and dilations, and extratruncular forms as limited or infiltrating. The tactics of treatment represent surgical and non-surgical methods or combined techniques. Surgical approaches utilize different tactics and techniques that are adopted based on the pathologic form and type of the malformation: (I) operation to reduce the haemodynamic activity of the malformation; (II) operation to eliminate the malformation; and (III) reconstructive operation. As for (I), a type of a tactic is the operation to derive the venous flow. In (II), the total or partial removal of the venous malformation is demonstrated subdivided into three different techniques. In this way, the infiltrating as well as the limited forms can be treated. An additional technique is dedicated to the treatment of a marginal vein. Approach (III) involves the treatment of venous aneurysms, where a variety of techniques have been successful. Long-term follow-up demonstrates positive results in 91% of the cases. Congenital predominantly venous malformations should be treated according to the principles developed during the past decades in vascular surgery, interventional treatment and multidisciplinary treatment. The days of predominantly conservative treatment should be relegated to the past. Special skills and experiences are necessary to carry out appropriate surgical strategy, and the required operative techniques should be dictated by the location and type of malformation and associated findings.

Clinical Aspects of Combination of Ceramic and Acrylic Occlusal Surfaces

Directory of Open Access Journals (Sweden)

Z. Ozhohan

2017-03-01

Full Text Available The objective of the research was to develop and substantiate the methods of constructing the occlusal surfaces when manufacturing aesthetic fixed restorations through the combination of different materials. Materials and methods. The study included 65 patients with ceramic and acrylic occlusal surfaces of aesthetic fixed dental prostheses. Group I included 21 patients with a combination of ceramic and acrylic occlusal surfaces. Group II included 22 patients with a combination of ceramic occlusal surfaces. Group III included 22 patients with a combination of acrylic occlusal surfaces. The patients were observed 3, 6 and 12 months after prosthetic repair. Results. The greatest increase in the occlusal contact surface area of fixed restorations was observed in Group I, that is, when combining dental prostheses with ceramic and acrylic occlusal surfaces. Considering uneven abrasion of the occlusal surfaces, we do not recommend to combine different materials when veneering the occlusal surface of the antagonistic teeth. Conclusions. This study demonstrated the important role of the correct combination of materials when veneering the occlusal surfaces. Physical and chemical properties of materials, namely the abrasion resistance play a significant role in the long-term denture functioning. The smallest increase in the occlusal contact surface area was observed in Group II when combining ceramic occlusal surfaces. It was due to a good abrasion resistance of ceramics as compared to acrylic resin as well as the presence of the glazed layer which prevents the premature abrasion of the occlusal surfaces of the antagonistic teeth due to lower surface roughness. The combination of acrylic resin and ceramics when constructing the occlusal surfaces of fixed restorations in Group I demonstrated the highest rate of the increase in the occlusal contact surface area – 9.93%. It was due to a low hardness of acrylic resin and its high surface roughness. In

The prevalence of questionable occlusal caries

DEFF Research Database (Denmark)

Makhija, Sonia K; Gilbert, Gregg H; Funkhouser, Ellen

2012-01-01

Questionable occlusal caries (QOC) can be defined as clinically suspected caries with no cavitation or radiographic evidence of occlusal caries. To the authors' knowledge, no one has quantified the prevalence of QOC, so this quantification was the authors' objective in conducting this study...

Computed tomography in basilar artery occlusion in childhood

International Nuclear Information System (INIS)

Mori, Koreaki; Miwa, Soichi; Handa, Hajime

1978-01-01

A case of basilar artery occlusion in a 13-year-old boy is presented. Eighteen other cases of such occlusion in childhood in the relevant literature were analyzed, and then all nineteen cases were compared to adult cases. In comparison with adult cases, the following points were clear: (1) In children as well as in adults, basilar artery occlusion is more common in males. (2) As is well known, arteriosclerosis is the commonest cause in adults. In children, however, idiopathic and/or congenital occlusion are more common causes. (3) The main clinical manifestations in childhood as well as in maturity are consciousness disturbance, hemiplegia or quadriplegia, and pupillary abnormalities. (4) An occlusion of the proximal third of the basilar artery is common in adults, whereas an occlusion of the middle third is common in childhood. (5) Diagnosis is based on clinical manifestations, cerebral angiography, and computed tomography. (6) In contrast to the poor prognosis in adults, the prognosis is fairly in children. (author)

Influence of the fast-processing technique on the number of the occlusal contacts and occlusal vertical dimension of complete dentures.

Science.gov (United States)

Atashrazm, Parsa; Alavijeh, Leila Zamani; Afshar, Maryam Sadat Sadrzadeh

2011-03-01

Occlusal errors during acryl processing affect the retention and stability of complete dentures. The aim of the present study was to assess the influence of a short curing technique on the number of occlusal contacts and the occlusal vertical dimension (OVD) of complete dentures. Complete dentures were prepared. The number of occlusal contacts was recorded in centric relation (CR) using 60 µ articulation paper. The OVD was recorded with the waxed trial denture in place. Dentures were then invested and processed with compression molding and short cure water bath technique. The number of occlusal contacts was recorded again. The amount of pin opening was measured for all of the complete dentures on the articulator. Data were analyzed with paired t-test to determine the alterations. The mean number of occlusal contacts before and after processing was 10.9 ± 2.4 and 6.3 ± 3.1 respectively (4.7 ± 1.9 decrease; p negative effect on the morphologic pattern of artificial teeth of complete dentures and thus should be used carefully.

A study on occlusal stability in shortened dental arches.

Science.gov (United States)

Sarita, Paulo T N; Kreulen, Cees M; Witter, Dick J; van't Hof, Martin; Creugers, Nico H J

2003-01-01

The aim of this study was to verify the hypothesis that shortened dental arches constitute a risk to occlusal stability. Using cluster samples, 725 subjects with shortened dental arches comprising intact anterior regions and zero to eight occluding pairs of posterior teeth and 125 subjects with complete dental arches were selected. Subjects with shortened dental arches were classified into eight categories according to arch length and symmetry. Parameters for occlusal stability were interdental spacing, occlusal tooth wear, occlusal contact of incisors in intercuspal position, and vertical and horizontal overlap. Additionally, tooth mobility and overeruption of unopposed teeth were assessed. Influence of independent variables (dental arch category, age, gender, and residence) on the parameters for occlusal stability was assessed by one-way ANOVA and Tukey's multiple range tests. Extreme shortened dental arches (zero to two pairs of occluding premolars) had significantly more interdental spacing, occlusal contact of incisors, and vertical overlap compared to complete dental arches. Occlusal wear and prevalence of mobile teeth were highest in these categories. The category with three to four occluding premolars had significantly more interdental spacing and, for the older age group, more anterior teeth in occlusal contact compared to complete dental arches. Age was consistently associated with increased changes in occlusal integrity. Signs of increased risk to occlusal stability seemed to occur in extreme shortened dental arches, whereas no such evidence was found for intermediate categories of shortened dental arches.

A spontaneous pre-anastomotic occlusion does not necessarily impair forearm native dialysis fistulas: echo-Doppler, 3D MR angiographic and digital subtraction angiographic imaging.

Science.gov (United States)

Verbeeck, N; Pillet, J C; Prospert, E; McLntyre, D; Lamy, S

2013-01-01

Renal transplantation is the choice treatment of end-stage renal disease. When it is not indicated or not immediately feasible, hemodialysis must be performed, preferably via a native arteriovenous fistula in the forearm. A pre-anastomotic occlusion of this type of fistula is often accompanied by a thrombosis of its draining vein. In some instances, the venous segment may remain permeable thanks to the development of arterial collateral pathways and may even allow efficient dialysis without any clinical syndrome of distal steal. We present the echo-Doppler, magnetic and angiographic characteristics of three of these collateralized shunts that have remained functional, in one of the cases following a percutaneous dilation.

Prevalence of lower extremity venous duplication

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Simpson William

2010-01-01

Full Text Available Purpose: This retrospective study was performed to determine the prevalence of lower extremity venous duplication using duplex ultrasound in the patient population of a large urban medical center. Materials and Methods: The reports of all lower extremity venous ultrasound examinations performed at our institution between January 1, 2002 and December 31, 2002 were reviewed. Ultrasound examinations that were performed for purposes other than the detection of lower extremity deep vein thrombosis were excluded. The prevalence of duplication and its specific location were recorded. In addition, the prevalence of thrombus and its specific location were also recorded. Results: A total of 3118 exams were performed in 2664 patients. Of the 2664 patients, 2311 had only one examination performed during the study period; 353 patients had more than one examination performed. We found that 10.1% of patients (270/2664 had at least one venous segment duplicated and 5.4% of patients (143/2664 had a thrombus in at least one venous segment. There was a statistically significant difference in the prevalence of both duplication and thrombus with a change in venous segment. Only 0.4% of patients (11/2664 had thrombus within a duplicated segment. Of those who had more than one examination performed, 15.3% (54/353 had the same venous segment(s seen on one examination but not another. Conclusion: Lower extremity venous duplication is a frequent anatomic variant that is seen in 10.1% of patients, but it may not be as common as is generally believed. It can result in a false negative result for deep vein thrombosis.

Occlusion Issues in Early Renaissance Art

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Barbara Gillam

2011-12-01

Full Text Available Early Renaissance painters innovatively attempted to depict realistic three-dimensional scenes. A major problem was to produce the impression of overlap for surfaces that occlude one another in the scene but are adjoined in the picture plane. Much has been written about perspective in art but little about occlusion. Here I examine some of the strategies for depicting occlusion used by early Renaissance painters in relation to ecological considerations and perceptual research. Perceived surface overlap is often achieved by implementing the principle that an occluding surface occludes anything behind it, so that occlusion perception is enhanced by a lack of relationship of occluding contour to occluded contours. Some well-known figure-ground principles are also commonly used to stratify adjoined figures. Global factors that assist this stratification include the placement of figures on a ground plane, a high viewpoint, and figure grouping. Artists of this period seem to have differed on whether to occlude faces and heads, often carefully avoiding doing so. Halos were either eliminated selectively or placed oddly to avoid such occlusions. Finally, I argue that the marked intransitivity in occlusion by architecture in the paintings of Duccio can be related to the issue of perceptual versus cognitive influences on the visual impact of paintings.

Modeling self-occlusions in dynamic shape and appearance tracking

KAUST Repository

Yang, Yanchao

2013-12-01

We present a method to track the precise shape of a dynamic object in video. Joint dynamic shape and appearance models, in which a template of the object is propagated to match the object shape and radiance in the next frame, are advantageous over methods employing global image statistics in cases of complex object radiance and cluttered background. In cases of complex 3D object motion and relative viewpoint change, self-occlusions and disocclusions of the object are prominent, and current methods employing joint shape and appearance models are unable to accurately adapt to new shape and appearance information, leading to inaccurate shape detection. In this work, we model self-occlusions and dis-occlusions in a joint shape and appearance tracking framework. Experiments on video exhibiting occlusion/dis-occlusion, complex radiance and background show that occlusion/dis-occlusion modeling leads to superior shape accuracy compared to recent methods employing joint shape/appearance models or employing global statistics. © 2013 IEEE.

Normal venous anatomy and physiology of the lower extremity.

Science.gov (United States)

Notowitz, L B

1993-06-01

Venous disease of the lower extremities is common but is often misunderstood. It seems that the focus is on the exciting world of arterial anatomy and pathology, while the topic of venous anatomy and pathology comes in second place. However, venous diseases such as chronic venous insufficiency, leg ulcers, and varicose veins affect much of the population and may lead to disability and death. Nurses are often required to answer complex questions from the patients and his or her family about the patient's disease. Patients depend on nurses to provide accurate information in terms they can understand. Therefore it is important to have an understanding of the normal venous system of the legs before one can understand the complexities of venous diseases and treatments. This presents an overview of normal venous anatomy and physiology.

Trombose venosa dos membros superiores Venous thrombosis of the upper limbs

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Waldemy Silva

2005-01-01

Full Text Available Foi realizada uma revisão da evolução clínica de 52 pacientes portadores de trombose venosa axilar e/ou subclávia. Na opinião do autor, até o presente não se tem evidência do esforço na patogenia dessa forma topográfica de trombose venosa. A terminologia síndrome de Paget-Schrötter pode ser usada quando existe um trombo, conforme sugeriram esses autores. No que diz respeito aos pacientes cujo quadro clínico têm como fator preponderante uma compressão extrínseca dos troncos venosos, deve-se levar em consideração uma outra síndrome, como a do desfiladeiro torácico. Para a confirmação de uma suspeita clínica de trombose venosa profunda, a flebografia é o padrão-ouro. O tratamento ideal da oclusão venosa axilo-subclávia não foi ainda estabelecido, mas o anticoagulante tem a preferência. A eficácia do efeito trombolítico in situ é contestada em publicações da literatura médica. O acesso cirúrgico direto para a trombectomia pode ser feito somente em condições especiais.Clinical course of 52 patients with axillary and/or subclavian vein thrombosis was reviewed. In the author's opinion, up to the present time we have no evidence of strain in the pathogenesis of this topographic vein thrombosis. The term Paget-Schrötter syndrome can be used when a thrombus is present, as these authors have suggested. With regard to the patients whose clinical picture is supported by an extrinsic compression on the venous trunks, another syndrome must be considered, such as the thoracic outlet syndrome. For the determination of a clinically suspected deep venous thrombosis, phlebography is the gold standard. The optimal treatment for the axillary-subclavian venous occlusion remains to be established, but the anticoagulant therapy has the preference. The efficacy of in situ thrombolytic effect is contested in medical publications. A direct surgical access for thrombectomy can be made only under special conditions.

Influence of denture adhesives on occlusion and disocclusion times.

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Abdelnabi, Mohamed Hussein; Swelem, Amal Ali; Al-Dharrab, Ayman A

2016-03-01

The effectiveness of adhesives in enhancing several functional aspects of complete denture performance has been well established. The direct influence of adhesives on occlusal contact simultaneity has not yet been investigated. The purpose of this crossover clinical trial was to evaluate quantitatively the influence of adhesives on occlusal balance by recording timed occlusal contacts; namely occlusion time (OT) and disocclusion time during right (DT-right) and left (DT-left) excursions by using computerized occlusal analysis. A crossover clinical trial was adopted. Assessments were carried out while participants (n=49) wore their dentures first without then with adhesives. Computerized occlusal analysis using the T-Scan III system was conducted to perform baseline computer-guided occlusal adjustment for conventionally fabricated dentures. Retention and stability assessment using the modified Kapur index and recording of OT and DT-right and DT-left values using the T-Scan III were subsequently carried out for all dentures, first without adhesives and then after application of adhesive. All T-Scan procedures were carried out by the same clinician. Wilcoxon signed-rank test was used to analyze the Kapur index scores and occlusal parameters (α=.05). Stability and retention of conventional dentures ranged initially from good to very good. However, adhesive application resulted in significant improvement (PAdhesives significantly decreased OT and DT durations in initially well-fitting complete dentures with fairly well balanced occlusion, and further enhanced denture stability and occlusal contact simultaneity. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Predictors of early stent occlusion among plastic biliary stents.

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Khashab, Mouen A; Kim, Katherine; Hutfless, Susan; Lennon, Anne Marie; Kalloo, Anthony N; Singh, Vikesh K

2012-09-01

A major disadvantage of plastic biliary stents is their short patency rates. The aim of this study was to identify predictors of early stent occlusion among patients receiving conventional plastic biliary stents. Early stent occlusion was defined as worsening cholestatic liver test results of a severity sufficiently significant to warrant ERCP with stent exchange prior to the planned stent exchange, or as symptoms of cholangitis. The association of cumulative stent diameter, demographics, stricture location, procedure indication, Charlson comorbidity index, history of prior early stent occlusion, presence of gallbladder, and performance of sphincteromy with the occurrence of early stent occlusion was studied using logistic regression and multivariate analysis. Our patient cohort comprised 343 patients (mean age 59.3 years) who underwent 561 ERCP procedures with the placement of one or more plastic biliary stents (mean number of stents per procedure 1.2, mean total diameter of stents per procedure 12 Fr). Early stent occlusion occurred in 73 (13 %) procedures. Female gender was protective against early stent occlusion (adjusted OR 0.54, 95 % CI 0.32-0.90, p = 0.02), while hilar stricture location was independently associated with a significantly increased risk of early stent occlusion (adjusted OR 3.41, 95 % CI 1.68-6.90, p = 0.0007). Early occlusion of conventional biliary stents occurred in 13 % of cases. While female gender decreased the risk of early stent occlusion, hilar stricture location was a significant predictor of early stent occlusion. Our results suggest that physicians should consider early elective stent exchange in patients with hilar strictures.

[Case report of occlusal treatment with full mouth reconstruction].

Science.gov (United States)

Oizumi, Makoto

2008-07-01

A 70-year-old woman presented with a complaint of masticatory pain and disturbance. She had collapse of occlusal support and vertical dimension decrease. This case used provisional restoration for increasing vertical dimension and reconstruction of anterior guidance. After confirming occlusal stability, she was treated with fixed prosthesis and removable partial dentures. This patient was followed for 6 and a half years with no prosthetic complications, because the reconstruction of bilateral occlusal support and anterior guidance were performed. It is important to reconstruct the occlusal support and anterior guidance in cases of prosthetic treatment of occlusal collapse.

[Occlusal schemes of complete dentures--a review of the literature].

Science.gov (United States)

Tarazi, E; Ticotsky-Zadok, N

2007-01-01

Occlusal scheme is defined as the form and the arrangement of the occlusal contacts in natural and artificial dentition. The choice of an occlusal scheme will determine the pattern of occlusal contacts between opposing teeth during centric relation and functional movement of the mandible. With dentures, the quantity and the intensity of these contacts determine the amount and the direction of the forces that are transmitted through the bases of the denture to the residual ridges. That is why the occlusal scheme is an important factor in the design of complete dentures. Three occlusal schemes are viewed in this review: bilateral balanced occlusion, monplane occlusion, and linear occlusion scheme. Each scheme represents a different concept of occlusion. Comparisons between these schemes are also reviewed and analyzed. The reasoning underlying the bilateral balanced occlusion scheme is that stability of the dentures is attained when bilateral contacts exist throughout all dynamic and static states of the denture during function. Anatomic teeth are used: the upper anterior teeth are set to satisfy aesthetics, and the posterior teeth are arranged in a compensatory curve and a medial curve. This scheme is adequate for well developed residual ridges, with skeletal class I relation. With highly resorbed residual ridges, the vectors of force that are transmitted through anatomic cusps will dislodge the lower denture and thus impair the comfort and efficiency of mastication experienced by the patient. In order to accommodate to the special needs posed by highly resorbed residual ridges and skeletal relations that are not class I, the monoplane scheme of occlusion was designed. This scheme consists of non anatomic (cuspless) teeth, which are set so that the anterior teeth provide the aesthetics, the premolars and the first molars are used for chewing, and the second molars do not occlude (although sometimes they are specifically used to establish bilateral contacts in lateral

Occlusal stability in shortened dental arches.

NARCIS (Netherlands)

Witter, D.J.; Creugers, N.H.J.; Kreulen, C.M.; Haan, A. de

2001-01-01

Shortened dental arches consisting of anterior and premolar teeth have been shown to meet oral functional demands. However, the occlusal stability may be at risk as a result of tooth migration. The aim of this nine-year study was to investigate occlusal stability in shortened dental arches as a

Venous injury in abusive head trauma

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Choudhary, Arabinda K. [Nemours A. I. duPont Hospital for Children, Department of Radiology, Wilmington, DE (United States); Bradford, Ray; Thamburaj, K.; Boal, Danielle K.B. [Hershey Medical Center, Department of Radiology, Hershey, PA (United States); Dias, Mark S. [Hershey Medical Center, Department of Neurosurgery, Hershey, PA (United States)

2015-11-15

Abusive head trauma (AHT) is an important cause of serious brain injury in infants and young children who have characteristic clinical and imaging findings that are discordant with the clinical history provided. Recent attention has focused on abnormalities of the cranial venous sinuses and cortical veins, both on MRI and at autopsy. Although many have interpreted these to be secondary to the AHT, some have recently argued that these venous abnormalities represent primary cortical sinus and venous thrombosis that leads secondarily to subdural hemorrhage and secondary brain injury. Direct trauma to the veins and sinuses has been reported at autopsy in AHT, but there has been no systematic study of venous abnormalities in cases of AHT. The purpose of this study was to define the incidence and characteristics of venous and sinus abnormalities in AHT. We included all children <36 months of age who were diagnosed with abusive head trauma between 2001 and 2012 and who had MRI and magnetic resonance (MR) venography as part of their diagnostic workup. We analyzed age, gender and clinical findings. MRI and MR venography were analyzed independently by two neuroradiologists with a focus on abnormalities involving the intracranial veins and venous sinuses. A total of 45 children were included. The median age was 3 months (range 15 days to 31 months) and 28 were boys (62%). Clinical findings included retinal hemorrhage in 71% and extracranial fractures in 55%. CT or MRI demonstrated subdural hemorrhage in 41 (91%); none had subdural effusions. In 31 cases (69%) MR venography demonstrated mass effect on the venous sinuses or cortical draining veins, with either displacement or partial or complete effacement of the venous structures from an adjacent subdural hematoma or brain swelling. We also describe the lollipop sign, which represents direct trauma to the cortical bridging veins and was present in 20/45 (44%) children. Evidence of displacement or compression of cortical veins

Venous injury in abusive head trauma

International Nuclear Information System (INIS)

Choudhary, Arabinda K.; Bradford, Ray; Thamburaj, K.; Boal, Danielle K.B.; Dias, Mark S.

2015-01-01

Abusive head trauma (AHT) is an important cause of serious brain injury in infants and young children who have characteristic clinical and imaging findings that are discordant with the clinical history provided. Recent attention has focused on abnormalities of the cranial venous sinuses and cortical veins, both on MRI and at autopsy. Although many have interpreted these to be secondary to the AHT, some have recently argued that these venous abnormalities represent primary cortical sinus and venous thrombosis that leads secondarily to subdural hemorrhage and secondary brain injury. Direct trauma to the veins and sinuses has been reported at autopsy in AHT, but there has been no systematic study of venous abnormalities in cases of AHT. The purpose of this study was to define the incidence and characteristics of venous and sinus abnormalities in AHT. We included all children <36 months of age who were diagnosed with abusive head trauma between 2001 and 2012 and who had MRI and magnetic resonance (MR) venography as part of their diagnostic workup. We analyzed age, gender and clinical findings. MRI and MR venography were analyzed independently by two neuroradiologists with a focus on abnormalities involving the intracranial veins and venous sinuses. A total of 45 children were included. The median age was 3 months (range 15 days to 31 months) and 28 were boys (62%). Clinical findings included retinal hemorrhage in 71% and extracranial fractures in 55%. CT or MRI demonstrated subdural hemorrhage in 41 (91%); none had subdural effusions. In 31 cases (69%) MR venography demonstrated mass effect on the venous sinuses or cortical draining veins, with either displacement or partial or complete effacement of the venous structures from an adjacent subdural hematoma or brain swelling. We also describe the lollipop sign, which represents direct trauma to the cortical bridging veins and was present in 20/45 (44%) children. Evidence of displacement or compression of cortical veins

Erythrocytes and von Willebrand factor in venous thrombosis

NARCIS (Netherlands)

Smeets, M.W.J.

2018-01-01

Venous thromboembolism represents the third leading vascular disease after myocardial infarction and stroke. Erythrocytes, the most abundant cells in venous thrombi, were thought to be innocent bystanders that become tangled up in the fibrin mesh of venous thrombi. However, this thesis describes

Long-term Outcome of Peripherally Implanted Venous Access Ports in the Forearm in Female Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Klösges, Laura, E-mail: l.kloesges@uni-bonn.de; Meyer, Carsten, E-mail: carsten.meyer@ukb.uni-bonn.de; Boschewitz, Jack, E-mail: jack.boschewitz@ukb.uni-bonn.de; Andersson, Magnus, E-mail: magnus.andersson@ukb.uni-bonn.de [Universitätsklinikum Bonn, Department of Radiology (Germany); Rudlowski, Christian, E-mail: c.rudlowski@evk.de [Evangelisches Krankenhaus Bergisch Gladbach, Department of Gynecology (Germany); Schild, Hans H., E-mail: hans.schild@ukb.uni-bonn.de [Universitätsklinikum Bonn, Department of Radiology (Germany); Wilhelm, Kai, E-mail: kai.wilhelm@ek-bonn.de [Ev. Kliniken Bonn, Johanniter-Krankenhaus, Department of Radiology (Germany)

2015-06-15

PurposeThe aim of this retrospective study was to analyze the long-term outcome of peripherally implanted venous access ports in the forearm at our institution in a female patient collective.MethodsBetween June 2002 and May 2011, a total of 293 female patients with an underlying malignancy had 299 forearm ports implanted in our interventional radiology suite. The mean age of the cohort was 55 ± 12 years (range 26–81 years). The majority of women suffered from breast (59.5 %) or ovarian cancer (28.1 %). Complications were classified as infectious complications, thrombotic and nonthrombotic catheter dysfunction (dislocation of the catheter or port chamber, fracture with/without embolization or kinking of the catheter, port occlusion), and others.ResultsWe analyzed a total of 90,276 catheter days in 248 port systems (47 patients were lost to follow-up). The mean device service interval was 364 days per catheter (range 8–2,132, median 223 days, CI 311–415, SD 404). Sixty-seven early (≤30 days from implantation) or late complications (>30 days) occurred during the observation period (0.74/1,000 catheter days). Common complications were port infection (0.18/1,000 days), thrombotic dysfunction (0.12/1,000 days), and skin dehiscence (0.12/1,000 days). Nonthrombotic dysfunction occurred in a total of 21 cases (0.23/1,000 days) and seemed to cumulate on the venous catheter entry site on the distal upper arm.ConclusionPeripherally implanted venous access ports in the forearm are a safe alternative to chest or upper-arm ports in female oncology patients. Special attention should be paid to signs of skin dehiscence and nonthrombotic dysfunction, especially when used for long-term treatment.

Onyx embolization as a first line treatment for intracranial dural arteriovenous fistulas with cortical venous reflux

International Nuclear Information System (INIS)

Panagiotopoulos, V.; Forsting, M.; Wanke, I.; Moeller-Hartmann, W.; Asgari, S.; Sandalcioglu, I.E.

2009-01-01

Our purpose was to present our experience regarding embolization of intracranial dural arteriovenous fistulas (DAVFs) with cortical venous reflux using Onyx, a non-adhesive liquid embolic agent. From January 2006 to December 2007, 16 patients (12 men and 4 women) with a mean age of 61 years (range 42 - 78) with an intracranial DAVF with cortical venous reflux underwent at least one transarterial embolization using Onyx. According to the Cognard classification, 2 lesions were grade V, 5 were grade IV, 6 were grade III, 2 were grade IIa+b, and 1 was grade IIb. The clinical presentation included 5 hemorrhagic deficits, 10 non-hemorrhagic manifestations, and 1 patient was asymptomatic. Twenty-four embolization sessions were performed in 16 patients with an average of 3 arterial feeders (range 1 - 9) embolized per DAVF. Immediately after embolization, complete occlusion was achieved in 9 / 16 (56 %) patients after the first session. Further postembolization surgical treatment was performed in 3 patients. Partial reperfusion occurred in 1 patient at the time of mean follow-up of 3.7 months (range 0 - 12). Treatment has been completed for 11 / 16 patients with angiographic cure in 10 / 11 (91 %). An infratentorial bleeding complication related to embolization occurred in one patient with temporary worsening of the patient's gait disturbance. At the time of mean clinical follow-up of 4.5 months (range 0 - 12), no procedure-related permanent morbidity was added to our cohort. According to our experience, embolization of intracranial DAVFs with cortical venous drainage using Onyx is feasible with promising results, indicating stability at the time of mid-term follow-up. In very complex DAVFs additional embolization material might be necessary, and in some cases surgery is warranted. (orig.)

'Chronic cerebrospinal venous insufficiency' in multiple sclerosis. Is multiple sclerosis a disease of the cerebrospinal venous outflow system?

International Nuclear Information System (INIS)

Wattjes, M.P.; Doepp, F.; Bendszus, M.; Fiehler, J.

2011-01-01

Chronic impaired venous outflow from the central nervous system has recently been claimed to be associated with multiple sclerosis (MS) pathology. This resulted in the term chronic cerebrospinal venous insufficiency (CCSVI) in MS. The concept of CCSVI is based on sonography studies showing that impaired venous outflow leading to pathological reflux is almost exclusively present in MS patients but not in healthy controls. Based on these findings, a new pathophysiological concept has been introduced suggesting that chronic venous outflow obstruction and venous reflux in the CNS result in pathological iron depositions leading to inflammation and neurodegeneration. The theory of CCSVI in MS has rapidly generated tremendous interest in the media and among patients and the scientific community. In particular, the potential shift in treatment concepts possibly leading to an interventional treatment approach including balloon angioplasty and venous stent placement is currently being debated. However, results from recent studies involving several imaging modalities have raised substantial concerns regarding the CCSVI concept in MS. In this review article, we explain the concept of CCSVI in MS and discuss this hypothesis in the context of MS pathophysiology and imaging studies which have tried to reproduce or refute this theory. In addition, we draw some major conclusions focusing in particular on the crucial question as to whether interventional treatment options are expedient. In conclusion, the present conclusive data confuting the theory of CCSVI in MS should lead to reluctance with respect to the interventional treatment of possible venous anomalies in MS patients. (orig.)

Influence of the quality of the finished occlusion on postretention occlusal relapse.

Science.gov (United States)

de Freitas, Karina Maria Salvatore; Janson, Guilherme; de Freitas, Marcos Roberto; Pinzan, Arnaldo; Henriques, José Fernando Castanha; Pinzan-Vercelino, Célia Regina Maio

2007-10-01

In this study, we aimed to evaluate the influence of the quality of the finished occlusion on postretention occlusal stability. The sample comprised 87 patients with Class I malocclusion, treated with extraction of the 4 first premolars and edgewise mechanics; they were divided into 2 groups, according to the quality of their finished occlusions. Group 1 included 44 subjects (23 boys, 21 girls) with posttreatment peer assessment rating (PAR) scores from 0 to 5. The mean pretreatment age was 13.74 years (SD 2.14). The mean treatment time was 1.92 years (SD 0.57), the mean retention time was 1.75 years (SD 0.96), and the mean time of posttreatment evaluation was 5.17 years (SD 1.82). Group 2 included 43 subjects (22 boys, 21 girls) with posttreatment PAR scores greater than 5. The mean initial age was 13.34 years (SD 1.35). The mean treatment time was 2.20 years (SD 0.66), the mean retention time was 1.77 years (SD 0.78), and the mean posttreatment evaluation was 5.47 years (SD 1.60). The PAR and the Little irregularity indexes were measured on the dental casts at pretreatment, posttreatment, and postretention. Intergroup comparisons were made with independent t tests, and the Pearson correlation coefficient was applied to the PAR score for the whole sample at the times evaluated. Well-finished patients had lower posttreatment and postretention PAR scores and greater changes during the treatment and posttreatment periods than did the poorly finished patients. For the Little irregularity index, the only difference between the groups was at the posttreatment stage; group 1 had a smaller irregularity score than group 2. The correlation coefficients showed that the greater the treatment changes, the smaller the posttreatment PAR score and the greater the relapse. But the higher the posttreatment PAR score, the higher the postretention PAR score. It was concluded that the greater the quality of the orthodontic finished occlusion, the greater are the treatment changes and

Revascularization Techniques for Acute Basilar Artery Occlusion : Technical Considerations and Outcome in the Setting of Severe Posterior Circulation Steno-Occlusive Disease.

Science.gov (United States)

Siebert, Eberhard; Bohner, Georg; Zweynert, Sarah; Maus, Volker; Mpotsaris, Anastasios; Liebig, Thomas; Kabbasch, Christoph

2018-04-12

To describe the clinical and radiological characteristics, frequency, technical aspects and outcome of endovascular treatment of acute basilar artery occlusion (ABO) in the setting of vertebrobasilar steno-occlusive disease. Retrospective analysis of databases of two universitary stroke centers including all consecutive patients from January 2013 until May 2017 undergoing thrombectomy for a) acute stroke due to basilar artery occlusion and either significant basilar artery stenosis or vertebral artery stenosis/occlusion as well as b) presumed embolic basilar artery occlusions. Demographics, stroke characteristics, time metrics, recanalization results and outcome were recorded. Interventional strategies were evaluated concerning the thrombectomy technique, additional angioplasty, type of approach with respect to lesion pattern (ipsilateral to steno-occlusive VA lesion: dirty road or contralateral: clean road) and sequence of actions. Out of 157 patients treated for ABO 38 (24.2%) had associated significant vertebrobasilar steno-occlusive lesions. An underlying significant basilar artery stenosis was present in 23.7% and additionally significant steno-occlusive vertebral lesions were present in 81.5%. Thrombectomy was performed with primary aspiration in 15.8% and with stent-retrievers in 84.2%. Successful revascularization (TICI 2b-3) was achieved in 86.8%. In 52.6% additional stent angioplasty was performed, in 7.9% balloon angioplasty only. The clean road approach was used in 22.5% of cases, the dirty road in 77.4%. Final modified Rankin scale (mRS) was 0-2 in 6 patients (15.8%) and 3-5 in 32 (84.2%). The in-hospital mortality was 36.8%. There were no statistically significant differences in outcome compared to presumed cases of embolisms. Endovascular treatment of ABO with underlying significant vertebrobasilar steno-occlusive lesions is effective and reasonably safe. Specific procedural strategies apply depending on individual patient pathology and anatomy

Eye movements and manual interception of ballistic trajectories: effects of law of motion perturbations and occlusions.

Science.gov (United States)

Delle Monache, Sergio; Lacquaniti, Francesco; Bosco, Gianfranco

2015-02-01

Manual interceptions are known to depend critically on integration of visual feedback information and experience-based predictions of the interceptive event. Within this framework, coupling between gaze and limb movements might also contribute to the interceptive outcome, since eye movements afford acquisition of high-resolution visual information. We investigated this issue by analyzing subjects' head-fixed oculomotor behavior during manual interceptions. Subjects moved a mouse cursor to intercept computer-generated ballistic trajectories either congruent with Earth's gravity or perturbed with weightlessness (0 g) or hypergravity (2 g) effects. In separate sessions, trajectories were either fully visible or occluded before interception to enforce visual prediction. Subjects' oculomotor behavior was classified in terms of amounts of time they gazed at different visual targets and of overall number of saccades. Then, by way of multivariate analyses, we assessed the following: (1) whether eye movement patterns depended on targets' laws of motion and occlusions; and (2) whether interceptive performance was related to the oculomotor behavior. First, we found that eye movement patterns depended significantly on targets' laws of motion and occlusion, suggesting predictive mechanisms. Second, subjects coupled differently oculomotor and interceptive behavior depending on whether targets were visible or occluded. With visible targets, subjects made smaller interceptive errors if they gazed longer at the mouse cursor. Instead, with occluded targets, they achieved better performance by increasing the target's tracking accuracy and by avoiding gaze shifts near interception, suggesting that precise ocular tracking provided better trajectory predictions for the interceptive response.

[Gnathosonics study of the occlusal stability of orthodontic patients].

Science.gov (United States)

Jiang, Ruo-Ping; Tyson, Kenneth W

2008-02-18

To analysis the stability of the occlusion before and after the orthodontic treatment by gnathosonics; To evaluate the reliability of the stethoscope method by comparing the subjective(stethoscopy) and objective(digital occlusal sound recording) methods of checking the occlusal sound. Sixty-four new patients with malocclusion were selected as the before treatment group, these patients were not subject to any previous orthodontic treatment, facial surgery or injury; the treatment complete group included 15 patients who were just debonded the fixed appliance. Both stethoscope and digital occlusal sound recording were used to evaluate the occlusal sound. The occlusal stability before and after orthodontic treatment was compared depending on the results from the objective examination. The stability of the occlusion between different types of malocclusion before treatment was compared also. The veracity and reliability of the stethoscope method were analysis using the objective method as the golden standard. (1) 43.75%(28/64) of the 64 new patients showed unstable occlusal sound. ANOVA test showed that there were no statistically significant differences between the unstable rates in different type of malocclusion. (2) 40% (6/15) of the 15 treatment complete patients had unstable occlusions. (3) There were no statistically significant differences between the unstable rate pre- and post-treatment. (4) The veracity of the stethoscopes was 81.01% (64/79). (5) Kappa test showed that the stethoscopes and the digital recording method were consistent; the Kappa value was 0.488, Pocclusion rate between the two groups, and between the different types of malocclusion before treatment. (2) Using stethoscopes method to check the occlusal sound is reliable. The veracity could be improved significantly with increased experiences.

Morphological characteristics of chronic total occlusion. Predictors of different strategies for long-segment femoral arterial occlusions

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Wei, Li-Ming; Zhu, Yue-Qi; Zhang, Pei-Lei; Lu, Hai-Tao; Zhao, Jun-Gong [Shanghai Jiaotong University Affiliated Sixth People' s Hospital, Department of Diagnostic and Interventional Radiology, Shanghai (China); Liu, Fang [Shanghai Jiaotong University Affiliated Sixth People' s Hospital, Department of Endocrinology, Shanghai (China)

2018-03-15

To investigate morphological characteristics used to predict recanalisation strategies in long-segment (>10 cm) femoral chronic total occlusion (LSF-CTO) angioplasty. We retrospectively evaluated a range of morphological CTA and DSA features in patients who underwent recanalisation of LSF-CTO. The stage of CTO was classified into early (3-12 months) and late (>12 months) according to estimated duration. Characteristics including stump morphology, lesion length and calcification, proximal side branches, collaterals circulation, runoff vessels and concomitant arterial occlusion were used as predictors, and multivariate logistic regression analysis was performed to identify variables associated with late-stage CTO and retrograde technique. A total of 119 patients with 137 CTOs in 137 limbs were enrolled. Overall, successful recanalisation was achieved in 122 CTOs (89.1%). Flush occlusion [odds ratio (OR) 2.958; 95% confidence interval (CI) 1.172-7.465; p = 0.022], large collateral (OR 2.778; 95% CI 1.201-6.427; p = 0.017) and TransAtlantic Inter-Society Consensus II class D (TASC D) lesion (OR 1.743; 95% CI 1.019-2.981; p = 0.042) were predictors for late-stage CTO. Flush occlusion (OR 75.278; 95% CI 10.664-531.384; p < 0.001) and large collateral (OR 23.213; 95% CI 3.236-166.523; p = 0.002) were associated with high likelihood for retrograde approach. Flush occlusion and large collateral were associated with a CTO at late-stage which may require retrograde recanalisation. (orig.)

VENOUS INSUFFICIENCY AND THROMBOEMBOLIC DISEASE IN BARIATRIC SURGERY PATIENTS

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Bonno van BELLEN

2013-09-01

Full Text Available Context Morbid obesity is associated with various co-morbidities, including chronic venous insufficiency. Bariatric surgery is the only effective treatment for morbid obesity, but with potential risks and possible complications, including venous thromboembolism. Objective To determine the prevalence of clinical and ultrasonographic signs of chronic venous insufficiency in morbid obese patients in preparation for bariatric surgery and the incidence of post-operative venous thromboembolic disease. Methods Patients on work-up for bariatric surgery of Centro Terapêutico Especializado em Fígado (CETEFI and Pro-Gastro surgical teams of the Hospital Beneficência Portuguesa de São Paulo were included. The analysed data were pre-operative findings for venous insufficiency (CEAP - clinical, etiological, anatomical, physiopathologic - classification and venous ultrassonographic findings, type of surgery (open or laparoscopic, abdominal circumference, body mass index (BMI and post-operative ultrassonography search for venous insufficiency and deep venous thrombosis. Results Between March 2007 and December 2009, 95 patients candidates for bariatric surgery had clinical and duplex scan evaluation of the lower limbs venous system. Of the 95 patients, 53 were submitted to the surgical procedure. There was a predominance of women (77.9%, the average age was 38.5 years, average preoperative weight 124.6 kg and average BMI of 45.5 kg/m2. Regarding obesity, 16.8% were obese, and 83.1% were morbidly obese. In relation to the venous findings, 86.3% of the patients did fit CEAP classification less than 3 and 13.7% greater than or equal to 3. Among the post-operative complications, there were four cases of wound infection. Three patients developed post-operative distal venous thrombosis (7.5%, but no one had clinically manifested pulmonary embolism. Conclusion No relation between BMI, CEAP classification and venous ultrassonographic findings were found. Although

Radiographic signs of non-venous placement of intended central venous catheters in children

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Taylor, Erin C. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); Taylor, George A. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); Harvard Medical School, Department of Radiology, Boston, MA (United States)

2016-02-15

Central venous catheters (CVCs) are commonly used in children, and inadvertent arterial or extravascular cannulation is rare but has potentially serious complications. To identify the radiographic signs of arterial placement of CVCs. We retrospectively reviewed seven cases of arterially malpositioned CVCs on chest radiograph. These cases were identified through departmental quality-assurance mechanisms and external consultation. Comparison of arterial cases was made with 127 age-matched chest radiographs with CVCs in normal, expected venous location. On each anteroposterior (AP) radiograph we measured the distance of the catheter tip from the right lateral border of the thoracic spine, and the angle of the vertical portion of the catheter relative to the midline. On each lateral radiograph we measured the angle of the vertical portion of each catheter relative to the anterior border of the thoracic spine. When bilateral subclavian catheters were present, the catheter tips were described as crossed, overlapping or uncrossed. On AP radiographs, arterially placed CVCs were more curved to the left, with catheter tip positions located farther to the left of midline than normal venous CVCs. When bilateral, properly placed venous catheters were present, all catheters crossed at the level of the superior vena cava (SVC). When one of the bilateral catheters was in arterial position, neither of the catheters crossed or the inter-catheter crossover distance was exaggerated. On lateral radiographs, there was a marked anterior angulation of the vertical portion of the catheter (mean angle 37 ± 15 standard deviation [SD] in arterial catheters versus 5.9 ± 8.3 SD in normally placed venous catheters). Useful radiographic signs suggestive of unintentional arterial misplacement of vascular catheters include leftward curvature of the vertical portion of the catheter, left-side catheter tip position, lack of catheter crossover on the frontal radiograph, as well as exaggerated

Venous anomalies and abnormalities of the posterior fossa

International Nuclear Information System (INIS)

Goulao, A.; Alvarez, H.; Garcia Monaco, R.; Pruvost, P.; Lasjaunias, P.

1990-01-01

The authors report a series of 16 patients with venous anomalies or abnormalities of the posterior fossa studied by angiography, CT and/or MRI. We believe that so-called 'venous angioma' are extreme anatomic variants that drain normal territories, and we prefer to call them developmental venous anomalies (DVA). Posterior fossa DVA, like the supra-tentorial ones are classified according to their drainage into deep and superficial type. They are exclusively located in the cerebellum or tectum. In 4 cases DVA was an incidental finding, in 3 an associated cerebral venous malformation (CVM) was found and felt to be the cause of the symptoms and only in one (Trigeminal pain) was a link between both suspected. Cavernous venous malformation (CVM) were found in frequent association with DVA (27%). 4 cases were single and 2 multiple. 5 CVM were located in the brain stem and 3 in the cerebellum. The clinical and radiological files were reviewed and a direct relationship between symptoms and localization was found in all patients with CVM. In 2 cases venous dysplasia was found: 1 Sturge-Weber and 1 First branchial arch syndrome. Both posterior fossa venous abnormalities were incidental findings. (orig.)

Hepatic venous pressure gradients measured by duplex ultrasound

International Nuclear Information System (INIS)

Tasu, J.-P.; Rocher, L.; Peletier, G.; Kuoch, V.; Kulh, E.; Miquel, A.; Buffet, C.; Biery, M.

2002-01-01

AIMS: The hepatic venous pressure gradient is a major prognostic factor in portal hypertension but its measurement is complex and requires invasive angiography. This study investigated the relationship between the hepatic venous pressure gradient and a number of Doppler measurements, including the arterial acceleration index. METHOD: We measured the hepatic venous pressure gradient in 50 fasting patients at hepatic venography. Immediately afterwards, a duplex sonographic examination of the liver was performed at which multiple measurements and indices of the venous and arterial hepatic vasculature were made. RESULTS: Hepatic arterial acceleration was correlated directly with the hepatic venous pressure gradient (r = 0.83, P -2 provided a positive predictive value of 95%, a sensitivity of 65% and a specificity of 95% for detecting patients with severe portal hypertension (hepatic venous pressure gradient > 12 mmHg). A correlation between the hepatic venous pressure gradient and the congestion index of the portal vein velocity (r = 0.45,P = 0.01) and portal vein velocity (r = 0.40,P = 0.044), was also noted. CONCLUSION: Measuring the hepatic arterial acceleration index may help in the non-invasive evaluation of portal hypertension. Tasu, J.-P. et al. (2002)

Concepts of occlusion in prosthodontics: A literature review, part I

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V Rangarajan

2015-01-01

Full Text Available Occlusion and its relationship to the function of the stomatognathic system have been widely studied in dentistry since many decades. This series of articles describe about occlusion in the complete denture, fixed partial denture, and implants. Part I and II of this articles series describe concepts and philosophies of occlusion in complete denture. So far, available research has not concluded a superior tooth form or occlusal scheme to satisfy the requirements of completely edentulous patients with respect to comfort, mastication, phonetics, and esthetics. Since then, several balanced and nonbalanced articulation concepts were proposed in the literature. A balanced articulation appears to be most appropriate because of tooth contacts observed during nonfunctional activities of patients. This article discusses about evolution of different concepts of occlusion and occlusal schemes in complete denture occlusion.

Depicting Occlusion in Early Renaissance Art

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Barbara Gillam

2011-05-01

Full Text Available The artist attempting to give the impression of three-dimensional relationships must convey somehow that one surface is in front of another. There is a large and venerable literature in Psychology on this subject, showing how figure-ground, border ownership and amodal completion and continuation are determined but there is almost no discussion of how artist's have recruited these and other principles to create convincing impressions of occlusion. Even Gombrich (Art & Illusion 1960 only considers the situation in which a figure has to be imagined from very partial cues, not how juxtaposed elements in art are parsed perceptually into occluding and occluded surfaces. In this paper I shall discuss approaches to occlusion present in early Renaissance art and the degree to which the principles now well-known to Psychologists were discovered and used, as artists increasingly depicted naturalistic scenes. Among the preoccupations of these artists, as indicated by their work, were whether and how much to occlude faces (and the related issue of the management of haloes, occlusion of and by architectural features, and the importance or otherwise of transitivity in occlusion relationships within the scene. They also clearly used the ground plane, high viewpoints and arrangements of contour terminations, as well as more conventional figural cues, to disambiguate perceived occlusion or to avoid the confusion of multiple surfaces.

Transcranial Doppler US as an alternative to angiography and balloon occlusion in estimating risk of carotid occlusion

International Nuclear Information System (INIS)

Feaster, S.H.; Powers, A.; Laws, E.R.

1990-01-01

This paper demonstrates the reliability of transcranial Doppler (TCD) US in the evaluation of the adequacy of collateral vessel cerebral blood flow in patients being considered for carotid ligation or occlusion. TCD was utilized in 12 patients in an attempt to study collateral vessel blood flow during endovascular balloon occlusion of a carotid artery. This was correlated with TCD measurements performed during manual carotid compression and with cerebral angiography. Changes of blood flow velocity were measured in the ipsilateral MCA and ACA. Excellent correlation was noted between the TCD measurements during manual carotid compression and actual endovascular balloon occlusion. There was also qualitative agreement with the cross-compression angiogram

Relationship of Occlusal Schemes with the Occurrence of Temporomandibular Disorders

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Dina H. Sugiaman

2013-07-01

Full Text Available Masticatory system is a complex functional unit of the body responsible for mastication, speech, and deglutition process. Temporomandibular disorders (TMD is used to describe all functional disturbances of the masticatory system. The etiology of TMD is multifactorial, such as occlusal disharmony and emotional stress. The relationship between occlusion and TMD has been highly debated in dentistry, one of the occlusal factors is the occlusal scheme. Occlusal schemes are defined as bilateral canine guidance, unilateral canine guidance, group function and balanced occlusion. However, studies about the relationship of occlusal schemes and the occurrence of the TMD are still limited and remained controversial. Objective: To investigate the relationship of occlusal schemes witht he occurrence of TMD. Methods: A cross-sectional study was conducted at the Faculty of Dentistry, Uniiversitas Indonesia. A total of 127 students were included in this study. Subjects were examined based on Clinical Helkimo Index and divided into TMD and non-TMD groups. Subjects were categorized as non-TMD groups if the value of the clinical Helkimo index was 0 and as TMD group when the value ranged between 1-25. Results: Balanced occlusion schemes has a greater risk of TMD occurrence with odds ratio value 5.6 and 95% confidence interval 1.188 to 26.331 (p=0.021. Conclusion: Balanced occlusion has a significant relationship with the occurrence of TMD.

Pulmonary venous abnormalities encountered on pre ...

African Journals Online (AJOL)

Multidetector computed tomography (MDCT) elegantly renders pulmonary venous anatomy. With increasing numbers of radiofrequency ablation procedures being performed, there is now a greater emphasis on pre-procedure imaging to delineate this anatomy. Pulmonary venous mapping studies can be performed with or ...

ENDOVASCULAR TREATMENT FOR DISORDERS OF THE VENOUS SYSTEM

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A. G. Osiev

2015-01-01

Full Text Available The annual rate of deep vein thrombosis in general population is from 5 to 9 cases per 10 000, whereas for venous thromboembolism (deep vein thrombosis and pulmonary embolism taken together amounts to 14 cases per 10 000. To improve longterm results of therapy for thrombosis of deep veins of the lower extremities, it is important to restore venous function and outflow. Anticoagulant therapy with low weight or non-fractionated heparin preparations remains the most widely used method of management. However, total or partial thrombosis resolution under anticoagulant treatment is achieved only in 4 and 14% of cases, respectively. Thrombolysis allows for early resorption of the thrombus by means of a minimally invasive procedure with lower risk of complication. After the venous flow is restored, the aim of treatment is to prevent damage to the venous valves, venous hypertension and repeated thrombosis with development of the post-thrombotic syndrome. Compared to anticoagulation, systemic thrombolysis has the benefit of more rapid clot resorption and less damage to the venous valve. One of its serious limitations is a high bleeding risk related to higher doses of the drug administered through a peripheral vein catheter. Therefore, selective intra-clot administration of thombolytics (direct catheter thrombolysis has been suggested as an alternative. For more effective therapy with the use of lower doses of thrombolytics, the so called pharmaco-mechanical thrombectomy has been developed. Venous stenosis hindering the venous outflow is frequently seen after direct catheter or pharmaco-mechanical thrombolysis. Angioplasty with stent placement is recommended in the cases with residual venous abnormality after successful thrombolysis and thrombectomy. 

Compression of the posterior fossa venous sinuses by epidural hemorrhage simulating venous sinus thrombosis: CT and MR findings

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Singh, Sumit; Ramakrishnaiah, Raghu H.; Hegde, Shilpa V.; Glasier, Charles M. [University of Arkansas for Medical Sciences, Pediatric Radiology, Little Rock, AR (United States)

2016-01-15

Posterior fossa dural venous sinus thrombus is a well-described complication of head trauma, especially when fracture crosses the dural sinus grooves or in association with epidural hemorrhage. We have found that post-traumatic posterior fossa epidural hematoma compressing a dural venous sinus can mimic dural venous thrombus. To discuss the CT and MRI findings of posterior fossa epidural hemorrhages simulating sinus thrombosis, to make radiologists aware of this important imaging pitfall. We describe radiologic findings in four children in whom a posterior fossa epidural hemorrhage mimicked dural venous sinus thrombus. Routine CT head and CT venography were obtained on Toshiba volume and helical CT scanners. MRI and MR venography were performed on a Philips scanner. In all cases there was medial displacement and compression of the posterior fossa dural venous sinuses without intraluminal thrombosis. The epidural hemorrhage was seen tracking along sinus grooves in the occipital bone, peeling the dura containing the sinuses from the calvarium and compressing the sinus, simulating thrombosis on axial CT views. Both venous sinus thrombosis and posterior fossa epidural hemorrhages in children are well-described complications of head trauma. Posterior fossa epidural hemorrhage can mimic a sinus thrombus by compressing and displacing the sinuses. It is important to recognize this pitfall because treatment of a suspected thrombus with anticoagulation can worsen epidural hemorrhage. (orig.)

Compression of the posterior fossa venous sinuses by epidural hemorrhage simulating venous sinus thrombosis: CT and MR findings

International Nuclear Information System (INIS)

Singh, Sumit; Ramakrishnaiah, Raghu H.; Hegde, Shilpa V.; Glasier, Charles M.

2016-01-01

Posterior fossa dural venous sinus thrombus is a well-described complication of head trauma, especially when fracture crosses the dural sinus grooves or in association with epidural hemorrhage. We have found that post-traumatic posterior fossa epidural hematoma compressing a dural venous sinus can mimic dural venous thrombus. To discuss the CT and MRI findings of posterior fossa epidural hemorrhages simulating sinus thrombosis, to make radiologists aware of this important imaging pitfall. We describe radiologic findings in four children in whom a posterior fossa epidural hemorrhage mimicked dural venous sinus thrombus. Routine CT head and CT venography were obtained on Toshiba volume and helical CT scanners. MRI and MR venography were performed on a Philips scanner. In all cases there was medial displacement and compression of the posterior fossa dural venous sinuses without intraluminal thrombosis. The epidural hemorrhage was seen tracking along sinus grooves in the occipital bone, peeling the dura containing the sinuses from the calvarium and compressing the sinus, simulating thrombosis on axial CT views. Both venous sinus thrombosis and posterior fossa epidural hemorrhages in children are well-described complications of head trauma. Posterior fossa epidural hemorrhage can mimic a sinus thrombus by compressing and displacing the sinuses. It is important to recognize this pitfall because treatment of a suspected thrombus with anticoagulation can worsen epidural hemorrhage. (orig.)

MR findings of cerebral venous sinus thrombosis

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Lim, Myung Kwan; Chang, Kee Hyun; Han, Moon Hee; Choi, Choong Gom [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1994-10-15

To describe MR findings of cerebral venous sinus thrombosis. We reviewed 11 MR images of six patients with cerebral venous sinus thrombosis. The MR images were retrospectively analyzed in terms of location and signal intensity of the thrombi, parenchymal lesions such as hemorrhage and edema, and changes in follow up study obtained in 4 patients. The thrombus in venous sinus was visualized on MRI in all six patients. The most frequently involved sites were superior sagittal sinus(n=4) and left transverse sinus(n=4). Signal intensity of the thrombus was isointense or hyperintense on both T1- and T2-weighted images with loss of normal signal void of the sinus on all sequences in all patients. Parenchymal lesion was patients in five of six cases, manifested as local hemorrhage in three and edema in three cases(one case overlapped). Local edema seen in three patients was completely resolved on follow up study of seven to 29 days intervals. It is concluded that iso- or high signal intensity with loss of signal void in venous sinus is virtually diagnostic of venous sinus thrombosis. If there are local parenchymal lesions such as hemorrhage and/or edema of unknown causes, cerebral venous sinus thrombosis should be included in differential diagnosis.

Part-time occlusion therapy for amblyopia in older children.

Science.gov (United States)

Singh, Inderpreet; Sachdev, Nishant; Brar, Gagandeep S; Kaushik, Sushmita

2008-01-01

To compare the efficacy of part-time versus full-time occlusion for treatment of amblyopia in children aged 7-12 years. Prospective interventional case series. One hundred children between 7-12 years of age with anisometropic (57), strabismic (25) and mixed (18) unilateral amblyopia were randomized (simple randomization) into four groups (25 each) to receive two hours, four hours, six hours or full-time occlusion therapy. Children were regularly followed up at six-weekly intervals for a minimum of three visits. Intragroup visual improvement was analyzed using paired t-test while intergroup comparisons were done using ANOVA and unpaired t-test. All four groups showed significant visual improvement after 18 weeks of occlusion therapy ( P amblyopia therapy with 11 eyes (44%), 17 eyes (68%), 22 eyes (88%) and 23 eyes (92%) being amblyopia responders in the four groups respectively, with the least number of responders in the two hours group. In mild to moderate amblyopia (vision 20/30 to 20/80), there was no significant difference in visual outcome among the four groups ( P =0.083). However, in severe amblyopia (vision 20/100 or worse), six hours ( P =0.048) and full-time occlusion ( P =0.027) treatment were significantly more effective than two hours occlusion. All grades of part-time occlusion are comparable to full-time occlusion in effectiveness of treatment for mild to moderate amblyopia in children between 7-12 years of age unlike in severe amblyopia, where six hours and full-time occlusion were more effective than two hours occlusion therapy.

Hydrocolloid occlusion for the treatment of neurovascular corns

DEFF Research Database (Denmark)

Petersen, Lars Jelstrup; Beck, Jan Walther; Reumert, L N

1991-01-01

The goal of this study was to determine the effect of hydrocolloid occlusion on neurovascular corns. The design was an observer-blinded, randomized, controlled study. Thirty consecutive patients participated in the trial. The patients received curettage alone or curettage with hydrocolloid...... occlusion. Six treatments were given over 12 weeks. A follow-up examination was performed 3 months after termination of the trial. Outcome measures were the size of the corns, a discomfort score, and an overall judgment of the trial. The results demonstrated no benefit of occlusion for symptoms or signs...... of neurovascular corns. The patients treated with occlusion were, however, generally more satisfied than the conventional group....

Radiation Retinopathy Associated with Central Retinal Vein Occlusion

Institute of Scientific and Technical Information of China (English)

Yan; Liu; FengWen

2007-01-01

Purpose: To report a case of radiation retinopathy associated with central retinal vein occlusion.Methods: The clinical features and fundus fluorescein angiography of this case were analyzed.Results: The patient had been treated with radiotherapy for her nasopharyngeal carcinoma, and presented with sudden visual loss in the left eye. The funduscopic examination and fluorescein angiography showed the features of radiation retinopathy in both eyes, and central retinal vein occlusion in the left eye.Conclusions: Radiation retinopathy can be associated with central retinal vein occlusion in the same eye, and it seems that the endothelial cell loss caused by radiation retinopathy may lead to retinal vein occlusion.

History of venous leg ulcers.

Science.gov (United States)

Gianfaldoni, S; Wollina, U; Lotti, J; Gianfaldoni, R; Lotti, T; Fioranelli, M; Roccia, M G

To retrieve the history of venous ulcers and of skin lesions in general, we must go back to the appearance of human beings on earth. It is interesting to note that cutaneous injuries evolved parallel to human society. An essential first step in the pathogenesis of ulcers was represented by the transition of the quadruped man to Homo Erectus. This condition was characterized by a greater gravitational pressure on the lower limbs, with consequences on the peripheral venous system. Furthermore, human evolution was characterized by an increased risk of traumatic injuries, secondary to his natural need to create fire and hunt (e.g. stones, iron, fire, animal fighting). Humans then began to fight one another until they came to real wars, with increased frequency of wounds and infectious complications. The situation degraded with the introduction of horse riding, introduced by the Scites, who first tamed animals in the 7th century BC. This condition exhibited iliac veins at compression phenomena, favouring the venous stasis. With time, man continued to evolve until the modern age, which is characterized by increased risk factors for venous wounds such as poor physical activity and dietary errors (1, 2).

Volumetric ambient occlusion for real-time rendering and games.

Science.gov (United States)

Szirmay-Kalos, L; Umenhoffer, T; Toth, B; Szecsi, L; Sbert, M

2010-01-01

This new algorithm, based on GPUs, can compute ambient occlusion to inexpensively approximate global-illumination effects in real-time systems and games. The first step in deriving this algorithm is to examine how ambient occlusion relates to the physically founded rendering equation. The correspondence stems from a fuzzy membership function that defines what constitutes nearby occlusions. The next step is to develop a method to calculate ambient occlusion in real time without precomputation. The algorithm is based on a novel interpretation of ambient occlusion that measures the relative volume of the visible part of the surface's tangent sphere. The new formula's integrand has low variation and thus can be estimated accurately with a few samples.

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

Sex-specific aspects of venous thrombosis

NARCIS (Netherlands)

Roach, Rachel Elizabeth Jo

2014-01-01

Venous thrombosis is a disease that occurs in 1-2 per 1000 people per year. At the time of their first venous thrombosis, approximately 50% of women are exposed to reproductive risk factors (oral contraception, postmenopausal hormone therapy, pregnancy and the puerperium). In this thesis, we showed

[Venous thrombosis associated with central venous catheter use in patients with cancer].

Science.gov (United States)

Iglesias Rey, Leticia; Fernández Pérez, Isaura; Barbagelata López, Cristina; Rivera Gallego, Alberto

2015-01-01

The use of central venous catheters for various applications (administration of chemotherapy, blood products and others) in patients with cancer is increasingly frequent. The association between thrombosis and catheter use has been fully established but aspects such as its causes, diagnosis, prophylaxis and treatment have not. We describe a case of thrombosis in a patient with cancer treated with chemotherapy who carried a central venous catheter. We also perform a review of the risk factors, the role of the prophylaxis and the treatment. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Prevalence of stenoses and occlusions of brain-supplying arteries in young stroke patients.

LENUS (Irish Health Repository)

von Sarnowski, Bettina

2013-03-06

OBJECTIVE: Atherosclerosis is believed to be a minor cause of TIA and stroke in younger and middle-aged patients. However, data from large cohorts are limited. This study investigates the prevalence of extracranial and intracranial atherosclerosis in stroke and TIA patients aged 18-55 years in the multinational sifap1 study. METHODS: From the sifap1 cohort (n = 5,023), we analyzed a subset of patients with complete data from carotid ultrasound studies. Patients with arterial dissections, vasculitis, and mobile thrombi were excluded. Among the remaining 2,187 patients (men: n = 1,319; 18-44 years: n = 744), intracranial arteries were additionally examined with ultrasonography in 1,612 patients (73.7%). Patients were stratified by sex and age groups (younger: 18-44 years; middle-aged: 45-55 years). RESULTS: In patients with ischemic stroke, the overall prevalence of carotid artery stenoses and occlusions was 8.9% (younger: 4.9%; middle-aged: 11.0%), of which 81% were symptomatic. Nonstenotic carotid plaques were more common in men than in women (15.8% vs 7.7%; p < 0.001), and in middle-aged than in younger patients (17.0% vs 4.9%; p < 0.001). Supratentorial intracranial artery stenoses and occlusions amounted to 11.8%. Supratentorial stenoses occurred more frequently in middle-aged patients (13.0% vs 7.8%; p < 0.001), whereas occlusions were equally common (both 3.2%; not significant). CONCLUSIONS: We observed a substantial proportion of atherosclerotic carotid artery stenoses and occlusions in younger stroke patients. Intracranial stenoses and occlusions were even more prevalent than extracranial carotid artery disease. Together with nonstenotic plaques, one-fifth of patients (21.2%) had symptomatic or asymptomatic large-artery atherosclerosis, which should encourage future stroke prevention campaigns to target risk factor modification in young people.

Intracranial developmental venous anomaly: is it asymptomatic?

Science.gov (United States)

Puente, A Bolívar; de Asís Bravo Rodríguez, F; Bravo Rey, I; Romero, E Roldán

2018-03-16

Intracranial developmental venous anomalies are the most common vascular malformation. In the immense majority of cases, these anomalies are asymptomatic and discovered incidentally, and they are considered benign. Very exceptionally, however, they can cause neurological symptoms. In this article, we present three cases of patients with developmental venous anomalies that presented with different symptoms owing to complications derived from altered venous drainage. These anomalies were located in the left insula, right temporal lobe, and cerebellum. The exceptionality of the cases presented as well as of the images associated, which show the mechanism through which the symptoms developed, lies in the low incidence of symptomatic developmental venous anomalies reported in the literature. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Venous sinus stenting for pseudotumour cerebri with venous sinus stenosis

International Nuclear Information System (INIS)

Chen Huairui; Bai Rulin; Wu Xiaojun; Qi Xiangqian; Mei Qiyong; Lu Yicheng

2011-01-01

Objective: To explore the relation between venous sinus stenosis and pseduotumour cerebri and to discuss the efficacy and strategy of venous sinus stenting for its treatment. Methods: Venous sinus stenting was performed in a total of 9 patients with pseudotumour cerebri accompanied by dural sinus stenosis. The clinical data, including the clinical presentations, intracranial pressure, angiographic findings, pressure of dural sinus,methods of treatment and the therapeutic results, were retrospectively analyzed. Results: Bilateral disc edema was seen in all patients. The pressure gradient in the lateral sinuses was obviously high before stenting (22.67±7.25)mmHg in all patients and a reduction in intra-sinus pressure and pressure gradient was also found (5.78±3.77)mmHg. The symptoms associated with intracranial hypertension were gradually improved or disappeared in two weeks after the placement of the stent in all cases, and the intracranial pressure dropped evidently (12.78±5.97)cm H 2 O. Vision was improved in 7 cases at three months, whereas it remained poor in 2 cases despite normalized intracranial pressure. There was no other permanent procedure-related morbidity. The patients were followed up for 3 months to 5 years, and no recurrence developed. Conclusion: Lateral sinus stenting is an effective method for the treatment of pseudotumour cerebri with dural sinus stenosis. (authors)

Effects of isokinetic calf muscle exercise program on muscle strength and venous function in patients with chronic venous insufficiency.

Science.gov (United States)

Ercan, Sabriye; Çetin, Cem; Yavuz, Turhan; Demir, Hilmi M; Atalay, Yurdagül B

2018-05-01

Objective The aim of this study was to observe the change of the ankle joint range of motion, the muscle strength values measured with an isokinetic dynamometer, pain scores, quality of life scale, and venous return time in chronic venous insufficiency diagnosed patients by prospective follow-up after 12-week exercise program including isokinetic exercises. Methods The patient group of this study comprised 27 patients (23 female, 4 male) who were diagnosed with chronic venous insufficiency. An exercise program including isokinetic exercise for the calf muscle was given to patients three days per week for 12 weeks. At the end of 12 weeks, five of the patients left the study due to inadequate compliance with the exercise program. As a result, control data of 22 patients were included. Ankle joint range of active motion, isokinetic muscle strength, pain, quality of life, and photoplethysmography measurements were assessed before starting and after the exercise program. Results Evaluating changes of the starting and control data depending on time showed that all isokinetic muscle strength measurement parameters, range of motion, and overall quality of life values of patients improved. Venous return time values have also increased significantly ( p < 0.05). Conclusion In conclusion, increase in muscle strength has been provided with exercise therapy in patients with chronic venous insufficiency. It has been determined that the increase in muscle strength affected the venous pump and this ensured improvement in venous function and range of motion of the ankle. In addition, it has been detected that pain reduced and quality of life improved after the exercise program.

Peripherally Placed Totally Implantable Venous-access Port Systems of the Forearm: Clinical Experience in 763 Consecutive Patients

International Nuclear Information System (INIS)

Goltz, Jan P.; Scholl, Anne; Ritter, Christian O.; Wittenberg, Guenther; Hahn, Dietbert; Kickuth, Ralph

2010-01-01

The aim of this study is to evaluate the effectiveness and safety of percutaneously placed totally implantable venous-access ports (TIVAPs) of the forearm. Between January 2006 and October 2008, peripheral TIVAPs were implanted in 763 consecutive patients by ultrasound and fluoroscopic guidance. All catheters were implanted under local anesthesia and were tunneled subcutaneously. Indication, technical success, and complications were retrospectively analyzed according to Society of Interventional Radiology (SIR) criteria. Presence of antibiotic prophylaxis, periprocedurally administered drugs (e.g., sedation), and laboratory results at the time of implantation were analyzed. Maintenance during the service interval was evaluated. In total, 327,499 catheter-days were analyzed. Technical success rate was 99.3%. Reasons for initial failure of implantation were either unexpected thrombosis of the subclavian vein, expanding tumor mass of the mediastinum, or failure of peripheral venous access due to fragile vessels. Mean follow-up was 430 days. There were 115 complications observed (15.1%, 0.03 per 100 catheter-days), of which 33 (4.3%) were classified as early (within 30 days from implantation) and 82 (10.7%) as late. Catheter-related venous thrombosis was found in 65 (8.5%) of 763 (0.02 per 100 catheter-days) TIVAPs. Infections were observed in 41 (5.4%) of 763 (0.01 per 100 catheter-days) devices. Other complications observed included dislocation of the catheter tip (0.8%), occlusion (0.1%), or rupture (0.1%) of the port catheter. Dislocated catheters were corrected during a second interventional procedure. In conclusion, implantation of percutaneously placed peripheral TIVAPs shows a high technical success rate and low risk of early complications when ultrasound and fluoroscopic guidance are used. Late complications are observed three times as often as early complications.

Clinicoroentgenological diagnosis of chronic venous ovarian insufficiency

International Nuclear Information System (INIS)

Grakova, L.S.; Galkin, E.V.; Naumova, E.B.

1989-01-01

The paper is devoted to clinicoroentgenological correlations of venous renogonadal hemodynamics in 168 women of reproductive age (151 women with infertility, habitual abortion, disordered menstrual function and 17 patients without disorders of the reproductive tract). Clinicolaboratory investigation was followed by visceral and parietal flebography for the detection of a pathological venous reflux into the ovarian pampiniform plexus. Clinicoroentgenological semiotics of chronic venous ovarian insufficiency was analyzed. Infertility was shown to be the main clinical manifestation of ovarian varicocele

Part-time occlusion therapy for amblyopia in older children

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Singh Inderpreet

2008-01-01

Full Text Available Aim: To compare the efficacy of part-time versus full-time occlusion for treatment of amblyopia in children aged 7-12 years. Materials and Methods: Prospective interventional case series. One hundred children between 7-12 years of age with anisometropic (57, strabismic (25 and mixed (18 unilateral amblyopia were randomized (simple randomization into four groups (25 each to receive two hours, four hours, six hours or full-time occlusion therapy. Children were regularly followed up at six-weekly intervals for a minimum of three visits. Statistical Analysis: Intragroup visual improvement was analyzed using paired t-test while intergroup comparisons were done using ANOVA and unpaired t-test. Results: All four groups showed significant visual improvement after 18 weeks of occlusion therapy ( P < 0.001. Seventy-three (73% of the total 100 eyes responded to amblyopia therapy with 11 eyes (44%, 17 eyes (68%, 22 eyes (88% and 23 eyes (92% being amblyopia responders in the four groups respectively, with the least number of responders in the two hours group. In mild to moderate amblyopia (vision 20/30 to 20/80, there was no significant difference in visual outcome among the four groups ( P =0.083. However, in severe amblyopia (vision 20/100 or worse, six hours ( P =0.048 and full-time occlusion ( P =0.027 treatment were significantly more effective than two hours occlusion. Conclusion: All grades of part-time occlusion are comparable to full-time occlusion in effectiveness of treatment for mild to moderate amblyopia in children between 7-12 years of age unlike in severe amblyopia, where six hours and full-time occlusion were more effective than two hours occlusion therapy.

REVIEW ARTICLE Venous thromboembolism associated with ...

Indian Academy of Sciences (India)

Navya

2017-03-24

Mar 24, 2017 ... Venous thromboembolism associated with protein S deficiency due to ... 2 Institute of Cardiology, Jagiellonian University Medical College, Kraków, Poland ... It has been long recognized that reduced PS activity is a risk factor for venous ... 1988). Sequencing of PROS1 gene intensified studies of genotype-.

[Occlusal anomalies in the deciduous and mixed bites].

Science.gov (United States)

Legovic, M; Mady, L

1998-01-01

In 311 examines (177 boys and 134 girls) with primary dentition and 535 examinees (285 boys and 250 girls) with mixed dentition in Istria--Croatia, the frequency of orthodontic and occlusive anomalies in regard of space plane and premature extraction of c, m1 and m2 are investigated. The orthodontic anomalies are defected in 46.95%, premature loss in 11.25% and occlusive anomalies in 40.85% of examinees with primary dentition, while in mixed dentition the 58.69% of examinees have orthodontic anomaly, the 17.20% premature loss and the 48.97% of examinees have occlusal anomaly. In both phases of dentition the most frequent are occlusive anomalies in the following planes: sagittal, vertical and sagittal-vertical.

Occlusal plane location in edentulous patients: a review.

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Shetty, Sanath; Zargar, Nazia Majeed; Shenoy, Kamalakanth; Rekha, V

2013-09-01

Occlusal plane orientation is an important factor in the construction of a complete denture. Occlusal plane could be oriented using landmarks in the mandibular arch as well as in the maxillary arch. In the mandibular arch there are few landmarks which could be used to orient the occlusal plane like the retromolar pad, corner of the lips (lower lip length) whereas the maxillary arch has a number of landmarks, of which the ala-tragal line is the most commonly used and the same being the most controversial. In the following article different landmarks and its accuracy for orientating the occlusal plane in an edentulous subject as studied by various authors has been discussed.

[Study on retention and stability of linear occlusal complete dentures].

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Zhang, Ping; Xu, Jun

2003-01-01

To learn retention and stability of linear occlusal complete dentures by investigating the subjective feelings of patient and the value of retention force. Static retention forces of maxillary and mandibular dentures were measured for 25 patients wearing linear occlusal dentures by using Hz-1 retention dynamometer. The subjective feelings of patients in functional state were gained simultaneously through questionnaire. Linear occlusal dentures demonstrate good retention in static and dynamic state. Among patients with severe resorption of residual ridge (RRR), mandibular linear occlusal dentures (shown good retentive subjective feelings) demonstrate significantly smaller retention force than those with slight or medium degree of RRR. There is no correlation between the subjective feelings and the values of retention forces of mandibular dentures. The subjective feelings of patients wearing new linear occlusal dentures are much better than that of old anatomic occlusal dentures. Linear occlusal dentures improve the performances of dentures by enhancing their stability during mastication movement.

Experimental occlusal interference induces long-term masticatory muscle hyperalgesia in rats.

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Cao, Ye; Xie, Qiu-Fei; Li, Kai; Light, Alan R; Fu, Kai-Yuan

2009-08-01

Temporomandibular joint or related masticatory muscle pain represents the most common chronic orofacial pain condition. Patients frequently report this kind of pain after dental alterations in occlusion. However, lack of understanding of the mechanisms of occlusion-related temporomandibular joint and muscle pain prevents treating this problem successfully. To explore the relationship between improper occlusion (occlusal interference) and masticatory muscle pain, we created an occlusal interference animal model by directly bonding a crown to a maxillary molar to raise the masticating surface of the tooth in rats. We raised the occlusal surface to three different heights (0.2, 0.4, and 0.6mm), and for one month we quantitatively measured mechanical nociceptive thresholds of the temporal and masseter muscles on both sides. Results showed a stimulus-response relationship between the height of occlusal interference and muscle hyperalgesia. Removal of the crown 6 days after occlusal interference showed that the removal at this time could not terminate the 1 month duration of mechanical hyperalgesia in the masticatory muscles. Lastly, we systemically administered NMDA antagonist MK801 (0.2, 0.1, and 0.05 mg/kg) to the treated rats and found that MK801 dose dependently attenuated the occlusal interference-induced hyperalgesia. These findings suggest that occlusal interference is directly related to masticatory muscle pain, and that central sensitization mechanisms are involved in the maintenance of the occlusal interference-induced mechanical hyperalgesia.

Portal-venous gas unrelated to mesenteric ischemia

International Nuclear Information System (INIS)

Wiesner, Walter; Mortele, Koenraad J.; Ji, Hoon; Ros, Pablo R.; Glickman, Jonathan N.

2002-01-01

The aim of this study was to report on 8 patients with all different non-ischemic etiologies for portal-venous gas and to discuss this rare entity and its potentially misleading CT findings in context with a review of the literature. The CT examinations of eight patients who presented with intrahepatic portal-venous gas, unrelated to bowel ischemia or infarction, were reviewed and compared with their medical records with special emphasis on the pathogenesis and clinical impact of portal-venous gas caused by non-ischemic conditions. The etiologies for portal-venous gas included: abdominal trauma (n=1); large gastric cancer (n=1); prior gastroscopic biopsy (n=1); prior hemicolectomy (n=1); graft-vs-host reaction (n=1); large paracolic abscess (n=1); mesenteric recurrence of ovarian cancer superinfected with clostridium septicum (n=1); and sepsis with Pseudomonas aeruginosa (n=1). The clinical outcome of all patients was determined by their underlying disease and not negatively influenced by the presence of portal-venous gas. Although the presence of portal-venous gas usually raises the suspicion of bowel ischemia and/or intestinal necrosis, this CT finding may be related to a variety of non-ischemic etiologies and pathogeneses as well. The knowledge about these conditions may help to avoid misinterpretation of CT findings, inappropriate clinical uncertainty and unnecessary surgery in certain cases. (orig.)

Postoperative deep venous thrombosis in Japan. Incidence and prophylaxis

International Nuclear Information System (INIS)

Inada, K.; Shirai, N.; Hayashi, M.; Matsumoto, K.; Hirose, M.

1983-01-01

The incidence of postoperative deep venous thrombosis was investigated using the iodine-125-fibrinogen method in 256 patients undergoing major surgery. Deep venous thrombosis was found in 49 patients (15.3 percent), and nonfatal pulmonary embolism developed in one of seven patients in whom the thrombus extended to the popliteal vein. The same investigation was performed in 110 patients who wore a graduated compression stocking on one leg, with the other leg serving as a control. Deep venous thrombosis was found in 4 of 110 stockinged legs (3.6 percent) and in 16 of 110 control legs (14.5 percent). The incidence of deep venous thrombosis decreased significantly in patients who wore the stocking. An increase in femoral venous flow velocity was found in the stockinged legs by the Doppler method. The mean velocity of venous return by xenon-133 clearance was significantly greater in the stockinged legs than in the control legs. These findings were considered to support the efficacy of graduated compression stockings for the prevention of deep venous thrombosis

Collation of chewing efficiency and dentures with diverse occlusal schemes

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Vijay Kumar Peddinti

2017-01-01

Full Text Available Background: Rehabilitation of an edentulous patient nurtures satisfaction and this lies in the chewing ability provided by the prosthesis. Aim: To evaluate and compare the masticatory efficiencies of complete dentures with different occlusal schemes. Materials and Methods: Fourteen completely edentulous patients from the age group of 50-70 years were selected according to the inclusion criteria followed in this study. The dentures were made with three different occlusal schemes, i.e., anatomic occlusion without balancing, anatomic occlusion with balancing, and lingualized occlusion and stored in water till the date of denture insertion. Post-insertion instructions were given to the patients at the time of delivery of the dentures. Patients were recalled after seven days and then masticatory efficiency was performed. The test was performed using boiled peanuts and Sieve system. Statistical Analysis: One-way analysis of variance (ANOVA test and unpaired t-test were carried out. Results: The obtained masticatory efficiency values with anatomic occlusion without balancing, anatomic occlusion with balancing, and lingualized occlusion LO were analyzed using one-way ANOVA test and unpaired “t” test. The tests showed that lingualized scheme had highest masticatory efficiency. Conclusion: Within the scope of this study, it can be concluded that the masticatory efficiency will be generally higher in patients provided with complete dentures fabricated using the lingualized occlusal scheme.

Congenital Retinal Macrovessel and the Association of Retinal Venous Malformations With Venous Malformations of the Brain.

Science.gov (United States)

Pichi, Francesco; Freund, K Bailey; Ciardella, Antonio; Morara, Mariachiara; Abboud, Emad B; Ghazi, Nicola; Dackiw, Christine; Choudhry, Netan; Souza, Eduardo Cunha; Cunha, Leonardo Provetti; Arevalo, J Fernando; Liu, T Y Alvin; Wenick, Adam; He, Lingmin; Villarreal, Guadalupe; Neri, Piergiorgio; Sarraf, David

2018-04-01

Congenital retinal macrovessel (CRM) is a rarely reported venous malformation of the retina that is associated with venous anomalies of the brain. To study the multimodal imaging findings of a series of eyes with congenital retinal macrovessel and describe the systemic associations. In this cross-sectional multicenter study, medical records were retrospectively reviewed from 7 different retina clinics worldwide over a 10-year period (2007-2017). Patients with CRM, defined as an abnormal, large, macular vessel with a vascular distribution above and below the horizontal raphe, were identified. Data were analyzed from December 2016 to August 2017. Clinical information and multimodal retinal imaging findings were collected and studied. Pertinent systemic information, including brain magnetic resonance imaging findings, was also noted if available. Of the 49 included patients, 32 (65%) were female, and the mean (SD) age at onset was 44.0 (20.9) years. A total of 49 eyes from 49 patients were studied. Macrovessel was unilateral in all patients. Color fundus photography illustrated a large aberrant dilated and tortuous retinal vein in all patients. Early-phase frames of fluorescein angiography further confirmed the venous nature of the macrovessel in 40 of 40 eyes. Optical coherence tomography angiography, available in 17 eyes (35%), displayed microvascular capillary abnormalities around the CRM, which were more evident in the deep capillary plexus. Of the 49 patients with CRM, 39 (80%) did not illustrate any evidence of ophthalmic complications. Ten patients (20%) presented with retinal complications, typically an incidental association with CRM. Twelve patients (24%) were noted to have venous malformations of the brain with associated magnetic resonance imaging. Of these, location of the venous anomaly in the brain was ipsilateral to the CRM in 10 patients (83%) and contralateral in 2 patients (17%), mainly located in the frontal lobe in 9 patients (75%). Our study has

Compliance with occlusion therapy for childhood amblyopia.

Science.gov (United States)

Wallace, Michael P; Stewart, Catherine E; Moseley, Merrick J; Stephens, David A; Fielder, Alistair R

2013-09-17

Explore compliance with occlusion treatment of amblyopia in the Monitored and Randomized Occlusion Treatment of Amblyopia Studies (MOTAS and ROTAS), using objective monitoring. Both studies had a three-phase protocol: initial assessment, refractive adaptation, and occlusion. In the occlusion phase, participants were instructed to dose for 6 hours/day (MOTAS) or randomized to 6 or 12 hour/day (ROTAS). Dose was monitored continuously using an occlusion dose monitor (ODM). One hundred and fifty-two patients (71 male, 81 female; 122 Caucasian, 30 non-Caucasian) of mean ± SD age 68 ± 18 months participated. Amblyopia was defined as an interocular acuity difference of at least 0.1 logMAR and was associated with anisometropia in 50, strabismus in 44, and both (mixed) in 58. Median duration of occlusion was 99 days (interquartile range 72 days). Mean compliance was 44%, mean proportion of days with no patch worn was 42%. Compliance was lower (39%) on weekends compared with weekdays (46%, P = 0.04), as was the likelihood of dosing at all (52% vs. 60%, P = 0.028). Compliance was lower when attendance was less frequent (P amblyopia type, and severity were not associated with compliance. Mixture modeling suggested three subpopulations of patch day doses: less than 30 minutes; doses that achieve 30% to 80% compliance; and doses that achieve around 100% compliance. This study shows that compliance with patching treatment averages less than 50% and is influenced by several factors. A greater understanding of these influences should improve treatment outcome. (ClinicalTrials.gov number, NCT00274664).

Hepatic venous pressure gradients measured by duplex ultrasound

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Tasu, J.-P.; Rocher, L.; Peletier, G.; Kuoch, V.; Kulh, E.; Miquel, A.; Buffet, C.; Biery, M

2002-08-01

AIMS: The hepatic venous pressure gradient is a major prognostic factor in portal hypertension but its measurement is complex and requires invasive angiography. This study investigated the relationship between the hepatic venous pressure gradient and a number of Doppler measurements, including the arterial acceleration index. METHOD: We measured the hepatic venous pressure gradient in 50 fasting patients at hepatic venography. Immediately afterwards, a duplex sonographic examination of the liver was performed at which multiple measurements and indices of the venous and arterial hepatic vasculature were made. RESULTS: Hepatic arterial acceleration was correlated directly with the hepatic venous pressure gradient (r = 0.83, P < 0.0001) and with the Child-Pugh score (r = 0.63, P < 0.0001). An acceleration index cut-off value of 1 m.s{sup -2} provided a positive predictive value of 95%, a sensitivity of 65% and a specificity of 95% for detecting patients with severe portal hypertension (hepatic venous pressure gradient > 12 mmHg). A correlation between the hepatic venous pressure gradient and the congestion index of the portal vein velocity (r = 0.45,P = 0.01) and portal vein velocity (r = 0.40,P = 0.044), was also noted. CONCLUSION: Measuring the hepatic arterial acceleration index may help in the non-invasive evaluation of portal hypertension. Tasu, J.-P. et al. (2002)

Venous, Arterialized-Venous, or Capillary Glucose Reference Measurements for the Accuracy Assessment of a Continuous Glucose Monitoring System

NARCIS (Netherlands)

Kropff, Jort; van Steen, Sigrid C.; deGraaff, Peter; Chan, Man W.; van Amstel, Rombout B. E.; DeVries, J. Hans

2017-01-01

Background: Different reference methods are used for the accuracy assessment of continuous glucose monitoring (CGM) systems. The effect of using venous, arterialized-venous, or capillary reference measurements on CGM accuracy is unclear. Methods: We evaluated 21 individuals with type 1 diabetes

Endovascular recanalization of native chronic total occlusions in patients with failed lower-extremity bypass grafts.

Science.gov (United States)

Wrigley, Clinton W; Vance, Ansar; Niesen, Timothy; Grilli, Christopher; Velez, J Daniel; Agriantonis, Demetrios J; Kimbiris, George; Garcia, Mark J; Leung, Daniel A

2014-09-01

To investigate the feasibility, safety, and outcome of endovascular recanalization of native chronic total occlusions (CTOs) in patients with failed lower-extremity bypass grafts. Retrospective review of 19 limbs in 18 patients with failed lower-extremity bypass grafts that underwent recanalization of native arterial occlusions between February 2009 and April 2013 was performed. Nine of the limbs presented with acute ischemia and 10 presented with chronic ischemia, including eight with critical limb ischemia and two with disabling claudication. The mean patency of the failed bypass grafts (63% venous) was 27 months. All limbs had Transatlantic Inter-Society Consensus class D lesions involving the native circulation. Technical success of the endovascular recanalization procedure was achieved in all but one limb (95%). The mean ankle brachial indices before and after treatment were 0.34 and 0.73, respectively. There were no major complications or emergency amputations. Mean patient follow-up was 64 weeks, and two patients were lost to follow-up. Primary patency rates at 3, 6, and 12 months were 87%, 48%, and 16%, respectively. Successful secondary procedures were performed in seven patients, with secondary patency rates at 3, 6, and 12 months of 88%, 73%, and 44%, respectively. Limb salvage rates at 12 and 24 months were 94% and 65%, and amputation-free survival rates at 12 and 24 months were 87% and 60%, respectively. Endovascular recanalization of native CTOs in patients with failed lower-extremity bypass grafts is technically feasible and safe and results in acceptable limb salvage. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

Diagnostics of defeats of venous collectors of brain

International Nuclear Information System (INIS)

Timofeeva, T.V.; Polunina, I.S.; Shcherbakova, E.Ya.; Kuldakova, S.V.

1997-01-01

Comparative data of transcranial ultrasonic dopplerography (170 patients) and radionuclidous antroscintigraphy (124), received during diagnostics of defects of venous collectors of brain are analyzed. Five variants of defeats of venous collectors (cross, sigmoid, internal of jugular of jugular vein), but also unpaired sine (direct, confluent) are described. Received results permit to reveal interrelation of infringements of venous outflow and increase of intracranial pressure

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

Predictors of Venous Thromboembolic Events Associated with Central Venous Port Insertion in Cancer Patients

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Christine Hohl Moinat

2014-01-01

Full Text Available Insertion of central venous port (CVP catheter in the cancer population is associated with increased incidence of venous thromboembolic events (VTE. However, trials have shown limited benefit of antithrombotic treatment to prevent catheter-related venous thrombosis. This prospective observational cohort study was designed to assess the incidence of VTE closely related to CVP implantation in patients with cancer and undergoing chemotherapy, and to identify a high risk subgroup of patients. Between February 2006 and December 2011, 1097 consecutive cancer patients with first CVP implantation were included. Catheter-related VTE were defined as deep venous thrombosis in the arm, with or without pulmonary embolism (PE, or isolated PE. The incidence of CVP-associated VTE was 5.9% (IC95 4.4–7.3% at 3 months, and 11.3% (IC95 9.4–13.2% at 12 months. The incidence of any VTE was 7.6% (IC95 6.0–9.3% at 3 months, and 15.3% (IC95 13.1–17.6% at 12 months. High Khorana risk score and lung cancer were significant predictors of 3 month VTE. In conclusion, this large cohort study of patients with first CVP catheter implantation confirms the high incidence of VTE associated with the CVP implantation and allow identifying high risk patients who may benefit from thromboprophylaxis.

A concept to transfer a therapeutic splint position into permanent occlusion with a customized lingual appliance.

Science.gov (United States)

Sachse, Tina; Schwestka-Polly, Rainer; Flieger, Stefanie; Wiechmann, Dirk

2012-05-21

The role of occlusion concerning temporomandibular disorder is still unclear but seems to be the only component of the stomathognathic system dentists are able to change morphologically. The aim of the paper is to describe the orthodontist's approach for transferring and maintaining a therapeutic splint position into permanent occlusion using a fully customized lingual appliance. Fixed acrylic bite planes on lower molars were used to maintain a symptom-free condyle position prior to orthodontic treatment. Silicone impressions of the arches including the fixed bite planes were used for the Incognito laboratory procedure. Two digital setups were made. One setup represents the target occlusion. A second setup including the bite planes was used to fabricate an additional set of lower molar brackets. In the leveling stage all teeth except the lower molars were settled to maintain the therapeutic condyle position. Finally, the fixed bite planes were stepwise removed and molar brackets were replaced to establish the permanent occlusion planned with the first setup. The advantage of an individual lingual appliance consists in the high level of congruence between the fabricated setups and the final clinical result. Both the individual scope for design and the precision of the appliance were vitally important in the treatment of a patient with a functional disorder of the masticatory system.

Mechanochemical endovenous ablation and new frontiers in venous intervention

NARCIS (Netherlands)

Boersma, D

2017-01-01

Venous insufficiency of the lower extremities is a common condition and related to various symptoms, including venous ulcers. The effect of venous insufficiency on patients’ health-related quality of life is substantial and comparable with other chronic diseases such as arthritis, diabetes, and

Pregnancy-related venous thromboembolism and risk of occult cancer

DEFF Research Database (Denmark)

Tarp Hansen, Anette; Veres, Katalin; Horváth-Puhó, Erzsébet

2017-01-01

The cancer risk during the first year after a pregnancy-related venous thromboembolism episode is higher than expected.An aggressive search for cancer in women with pregnancy-related venous thromboembolism is probably not warranted, due to low absolute risk.......The cancer risk during the first year after a pregnancy-related venous thromboembolism episode is higher than expected.An aggressive search for cancer in women with pregnancy-related venous thromboembolism is probably not warranted, due to low absolute risk....

Pregnancy-related venous thromboembolism and risk of occult cancer

DEFF Research Database (Denmark)

Hansen, Anette Tarp; Veres, Katalin; Horváth-Puhó, Erzsébet

2017-01-01

The cancer risk during the first year after a pregnancy-related venous thromboembolism episode is higher than expected. An aggressive search for cancer in women with pregnancy-related venous thromboembolism is probably not warranted, due to low absolute risk.......The cancer risk during the first year after a pregnancy-related venous thromboembolism episode is higher than expected. An aggressive search for cancer in women with pregnancy-related venous thromboembolism is probably not warranted, due to low absolute risk....

Central venous catheters: the role of radiology

International Nuclear Information System (INIS)

Tan, P.L.; Gibson, M.

2006-01-01

The insertion and management of long-term venous catheters have long been the province of anaesthetists, intensive care physicians and surgeons. Radiologists are taking an increasing role in the insertion of central venous catheters (CVCs) because of their familiarity with the imaging equipment and their ability to manipulate catheters and guide-wires. The radiological management of the complications of CVCs has also expanded as a result. This article reviews the role of radiology in central venous access, covering the detection and management of their complications

Systemic Venous Inflow to the Liver Allograft to Overcome Diffuse Splanchnic Venous Thrombosis

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Cristian Lupascu

2015-01-01

Full Text Available Diffuse splanchnic venous thrombosis (DSVT, formerly defined as contraindication for liver transplantation (LT, is a serious challenge to the liver transplant surgeon. Portal vein arterialisation, cavoportal hemitransposition and renoportal anastomosis, and finally combined liver and small bowel transplantation are all possible alternatives to deal with this condition. Five patients with preoperatively confirmed extensive splanchnic venous thrombosis were transplanted using cavoportal hemitransposition (4x and renoportal anastomosis (1x. Median follow-up was 58 months (range: 0,5 to 130 months. Two patients with previous radiation-induced peritoneal injury died, respectively, 18 days and 2 months after transplantation. The three other patients had excellent long-term survival, despite the fact that two of them needed a surgical reintervention for severe gastrointestinal bleeding. Extensive splanchnic venous thrombosis is no longer an absolute contraindication to liver transplantation. Although cavoportal hemitransposition and renoportal anastomosis undoubtedly are life-saving procedures allowing for ensuring adequate allograft portal flow, careful follow-up of these patients remains necessary as both methods are unable to completely eliminate the complications of (segmental portal hypertension.

Cerebrofacial venous metameric syndrome (CVMS) 3: Sturge-Weber syndrome with bilateral lymphatic/venous malformations of the mandible

International Nuclear Information System (INIS)

Ramli, N.; Sachet, M.; Bao, C.; Lasjaunias, P.

2003-01-01

We present a case of Sturge-Weber syndrome with a bilateral lymphatic/venous malformation of the mandible. Modern biology suggests an explanation for such a case. The classification of cerebrofacial venous metameric syndromes (CVMS) enables us to recognise this lesion as involving the most caudal of the cranial metamere (CVMS 3). (orig.)

Facial expression recognition under partial occlusion based on fusion of global and local features

Science.gov (United States)

Wang, Xiaohua; Xia, Chen; Hu, Min; Ren, Fuji

2018-04-01

Facial expression recognition under partial occlusion is a challenging research. This paper proposes a novel framework for facial expression recognition under occlusion by fusing the global and local features. In global aspect, first, information entropy are employed to locate the occluded region. Second, principal Component Analysis (PCA) method is adopted to reconstruct the occlusion region of image. After that, a replace strategy is applied to reconstruct image by replacing the occluded region with the corresponding region of the best matched image in training set, Pyramid Weber Local Descriptor (PWLD) feature is then extracted. At last, the outputs of SVM are fitted to the probabilities of the target class by using sigmoid function. For the local aspect, an overlapping block-based method is adopted to extract WLD features, and each block is weighted adaptively by information entropy, Chi-square distance and similar block summation methods are then applied to obtain the probabilities which emotion belongs to. Finally, fusion at the decision level is employed for the data fusion of the global and local features based on Dempster-Shafer theory of evidence. Experimental results on the Cohn-Kanade and JAFFE databases demonstrate the effectiveness and fault tolerance of this method.

Occlusal caries risk assessment using Cariogram analysis in student aged 11-12 years

Directory of Open Access Journals (Sweden)

Riana Wardani

2017-03-01

Full Text Available ABSTRACT   Introduction: Basic Health Research 2013 showed Dental Caries Index in school age student in West Java was lower than the expected target, with occlusal surface as most affected part. The purpose of this study was to determine the risk status of dental caries in school age student by using cariogram analysis. Methods: Observational research. Study was conducted on 30 student aged 11-12 years with caries high risk on occlusal surfaces. Purposive sampling was taken from students of SDN Cikawari and SDN Mekarjaya Bandung Regency with high DMF-S index. Inclusion criteria: male and female, aged 11-12 years, good systemic health, SDN Mekarjaya and SDN Cikawari Bandung Regency students. Exclusion criteria: suffering from systemic disorder, currently in long-term antibiotic therapy, orthodontic appliance usage. Case history, eating habits and intake of fluoride, caries experience, salivary volume and buffering capacity of each sample was examined using cariogram examination method. Results: The cariogram analysis showed 43% chance of caries avoidance. Diet control was 23.3%, includes two factors: sugary foods and eating frequency. Bacteria control was 11.9% by evaluating both bacterial factors (the amount of plaque and the bacteria Streptococcus mutans. Vulnerability control was 14.4%, including caries prevention by the continuation of fluorine program and other conditions control that affect salivary secretions. Conclusion: Based on cariogram analysis found that all samples who had occlusal surfaces caries were at a high risk category, but still having moderate potential of avoiding new caries occurrence by controlling risk factors. Keywords: Cariogram analysis, Occlusal caries, Aged 11-12 years

Imaging of head and neck venous malformations

International Nuclear Information System (INIS)

Flis, Christine M.; Connor, Stephen E.

2005-01-01

Venous malformations (VMs) are non proliferative lesions that consist of dysplastic venous channels. The aim of imaging is to characterise the lesion and define its anatomic extent. We will describe the plain film, ultrasound (US) (including colour and duplex Doppler), computed tomography (CT), magnetic resonance imaging (MRI), conventional angiographic and direct phlebographic appearances of venous malformations. They will be illustrated at a number of head and neck locations, including orbit, oral cavity, superficial and deep facial space, supraglottic and intramuscular. An understanding of the classification of such vascular anomalies is required to define the correct therapeutic procedure to employ. Image-guided sclerotherapy alone or in combination with surgery is now the first line treatment option in many cases of head and neck venous malformations, so the radiologist is now an integral part of the multidisciplinary management team. (orig.)

Cardiovascular Pressures with Venous Gas Embolism and Decompression

Science.gov (United States)

Butler, B. D.; Robinson, R.; Sutton, T.; Kemper, G. B.

1995-01-01

Venous gas embolism (VGE) is reported with decompression to a decreased ambient pressure. With severe decompression, or in cases where an intracardiac septal defect (patent foramen ovale) exists, the venous bubbles can become arterialized and cause neurological decompression illness. Incidence rates of patent foramen ovale in the general population range from 25-34% and yet aviators, astronauts, and deepsea divers who have decompression-induced venous bubbles do not demonstrate neurological symptoms at these high rates. This apparent disparity may be attributable to the normal pressure gradient across the atria of the heart that must be reversed for there to be flow potency. We evaluated the effects of: venous gas embolism (0.025, 0.05 and 0.15 ml/ kg min for 180 min.) hyperbaric decompression; and hypobaric decompression on the pressure gradient across the left and right atria in anesthetized dogs with intact atrial septa. Left ventricular end-diastolic pressure was used as a measure of left atrial pressure. In a total of 92 experimental evaluations in 22 dogs, there were no reported reversals in the mean pressure gradient across the atria; a total of 3 transient reversals occurred during the peak pressure gradient changes. The reasons that decompression-induced venous bubbles do not consistently cause serious symptoms of decompression illness may be that the amount of venous gas does not always cause sufficient pressure reversal across a patent foramen ovale to cause arterialization of the venous bubbles.

Core content for training in venous and lymphatic medicine.

Science.gov (United States)

Zimmet, Steven E; Min, Robert J; Comerota, Anthony J; Meissner, Mark H; Carman, Teresa L; Rathbun, Suman W; Jaff, Michael R; Wakefield, Thomas W; Feied, Craig F

2014-10-01

The major venous societies in the United States share a common mission to improve the standards of medical practitioners, the educational goals for teaching and training programs in venous disease, and the quality of patient care related to the treatment of venous disorders. With these important goals in mind, a task force made up of experts from the specialties of dermatology, interventional radiology, phlebology, vascular medicine, and vascular surgery was formed to develop a consensus document describing the Core Content for venous and lymphatic medicine and to develop a core educational content outline for training. This outline describes the areas of knowledge considered essential for practice in the field, which encompasses the study, diagnosis, and treatment of patients with acute and chronic venous and lymphatic disorders. The American Venous Forum and the American College of Phlebology have endorsed the Core Content. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Chronic venous disorders

African Journals Online (AJOL)

The San Valentino Vascular Screening Project conducted in Italy found a ... developed healthcare systems, the cost of treating advanced venous disease ..... tissue inflammation and necrosis. Sclerosing ... and for its tributaries as an alternative.

Venous Thromboembolism in Patients With Thrombocytopenia

DEFF Research Database (Denmark)

Bælum, Jens Kristian; Ellingsen Moe, Espen; Nybo, Mads

2017-01-01

BACKGROUND: Venous thromboembolism (VTE) is a frequent and potentially lethal condition. Venous thrombi are mainly constituted of fibrin and red blood cells, but platelets also play an important role in VTE formation. Information about VTE in patients with thrombocytopenia is, however, missing. O...... having thrombocytopenia with VTE seem to be safely treated with anticoagulants without increased occurrence of bleeding....

A BMPy Road for Venous Development.

Science.gov (United States)

Goddard, Lauren M; Kahn, Mark L

2017-09-11

Detailed molecular pathways for the specific growth of arteries and lymphatic vessels have been identified, but the mechanisms controlling venous vessel growth have been obscure. Tischfield and colleagues (2017) shed new light on this problem by identifying a role for BMP signaling in development of the cerebral venous system. Copyright © 2017 Elsevier Inc. All rights reserved.

Duplex imaging of residual venous obstruction to guide duration of therapy for lower extremity deep venous thrombosis.

Science.gov (United States)

Stephenson, Elliot J P; Liem, Timothy K

2015-07-01

Clinical trials have shown that the presence of ultrasound-identified residual venous obstruction (RVO) on follow-up scanning may be associated with an elevated risk for recurrence, thus providing a potential tool to help determine the optimal duration of anticoagulant therapy. We performed a systematic review to evaluate the clinical utility of post-treatment duplex imaging in predicting venous thromboembolism (VTE) recurrence and in adjusting duration of anticoagulation. The Ovid MEDLINE Database, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Database of Abstracts of Reviews of Effects were queried for the terms residual thrombus or obstruction, duration of therapy, deep vein thrombosis, deep venous thrombosis, DVT, venous thromboembolism, VTE, antithrombotic therapy, and anticoagulation, and 228 studies were selected for review. Six studies determined the rate of VTE recurrence on the basis of the presence or absence of RVO. Findings on venous ultrasound scans frequently remained abnormal in 38% to 80% of patients, despite at least 3 months of therapeutic anticoagulation. In evaluating for VTE recurrence, the definition of RVO varied widely in the literature. Some studies have shown an association between RVO and VTE recurrence, whereas other studies have not. Overall, the presence of RVO is a mild risk factor for recurrence (odds ratio, 1.3-2.0), but only when surveillance imaging is performed soon after the index deep venous thrombosis (3 months). RVO is a mild risk factor for VTE recurrence. The presence or absence of ultrasound-identified RVO has a limited role in guiding the duration of therapeutic anticoagulation. Further research is needed to evaluate its utility relative to other known risk factors for VTE recurrence. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Improving venous leg ulcer management

OpenAIRE

Weller, Carolina Dragica

2017-01-01

This thesis reports several different methods to develop and evaluate complex interventions designed to improve venous leg ulcer management. Chronic venous leg ulcers (VLU) are the most common chronic wound problem in the community. Its health and economic burden is predicted to increase due to ageing of the community and increase in prevalence of diabetes and obesity. Although many patients seek health care for VLU, most do not receive the most effective management. Patients with this condi...

Compression therapies for chronic venous leg ulcers: interventions and adherence

Directory of Open Access Journals (Sweden)

Latz CA

2015-01-01

Full Text Available Christopher A Latz,1 Kellie R Brown,2 Ruth L Bush11Texas A&M Health Science Center College of Medicine, Bryan, TX, USA; 2Medical College of Wisconsin, Milwaukee, WI, USAAbstract: Compression therapy has been the mainstay for the treatment of lower extremity edema, venous insufficiency, and particularly, venous ulcerative disease. Though modern surgical treatments exist, none are completely effective without good compressive options to allow for decreased swelling and better oxygenation of damaged tissues. This review article will describe the pathophysiology and presentation of lower extremity venous ulcerations, as well as current options for compression therapy. The benefits, along with the major pitfall of nonadherence, will also be discussed.Keywords: venous disease, chronic venous insufficiency, venous ulceration

Intramedullary Venous Drainage System for Distal Fingertip Replantations.

Science.gov (United States)

Purisa, Husrev; Ozturk, Muhammed Besir; Kabakas, Fatih; Mersa, Berkan; Ozcelik, Ismail Bulent; Sezer, Ilker

2017-08-01

The number of venous anastomoses performed during fingertip replantation is one of the most important factors affecting the success of replantation. However, because vessel diameters decrease in the zone 1 level, vessel anastomoses, especially vein anastomoses, are technically difficult and, thus, cannot be performed in most cases. Alternative venous drainage methods are crucial when any reliable vein repair is not possible. In the literature, so many artery-only replantation techniques have been defined, such as arteriovenous anastomoses, forming an arteriovenous or venocutaneous fistula, manual milking and massage, puncturing, and external bleeding via a fishmouth incision and using a medical leech. It has been shown that, in distal fingertip replantations, the medullary cavity may also be a good way for venous return. In this study, we introduce an alternative intramedullary venous drainage system we developed to facilitate venous drainage in artery-only fingertip replantations. The results of 24 fingertip replantations distal to the nail fold by using this system are presented with a literature review.

Preprosthetic therapy utilizing a temporary occlusal acrylic splint: a case report.

Science.gov (United States)

Badel, Tomislav; Kraljeviç, Sonja; Panduriç, Josip; Marotti, Miljenko

2004-05-01

This case report describes the complex occlusal rehabilitation of a patient with signs and symptoms of temporomandibular disorders with utilization of an occlusal acrylic splint as a means of initial treatment for neuromuscular reprogramming and repositioning of the condyle within the mandibular fossa for occlusal stability, thus allowing adaptation to a new occlusal vertical dimension.

Intravitreal triamcinolone acetonide injections in the treatment of retinal vein occlusions.

Science.gov (United States)

Roth, Daniel B; Cukras, Catherine; Radhakrishnan, Ravi; Feuer, William J; Yarian, David L; Green, Stuart N; Wheatley, Harold M; Prenner, Jonathan

2008-01-01

To report the visual acuity response after intravitreal triamcinolone injection in patients with macular edema due to retinal vein occlusions. Retrospective nonrandomized interventional series of 172 consecutive patients with macular edema due to retinal vein occlusions who were treated with intravitreal triamcinolone acetonide injection. Patients underwent Snellen visual acuity testing and ophthalmoscopic examination at baseline and 1, 3, 6, and 12 months after intravitreal triamcinolone acetonide injection. All subtypes of retinal vein occlusions showed significant improvements in mean visual acuity 1 month after injection. This improvement in visual acuity was maintained over the 12-month period for all but the central retinal vein occlusion group. Seventy-one (41.3%) of the 172 patients received more than one intravitreal triamcinolone injection for unresolved or recurrent macular edema. This study demonstrates a benefit associated with intravitreal triamcinolone acetonide injection for retinal vein occlusions that was maintained by patients with branch retinal vein occlusions and hemiretinal vein occlusions over a 12-month period. Visual acuity improvement was not maintained in patients with central retinal vein occlusions with this course of treatment.

Venous compression syndrome of internal jugular veins prevalence in patients with multiple sclerosis and chronic cerebro-spinal venous insufficiency.

Science.gov (United States)

Mandolesi, Sandro; Niglio, Tarcisio; Orsini, Augusto; De Sio, Simone; d'Alessandro, Alessandro; Mandolesi, Dimitri; Fedele, Francesco; d'Alessandro, Aldo

2016-01-01

Analysis of the incidence of Venous Compression Syndrome (VCS) with full block of the flow of the internal jugular veins (IJVs) in patients with Multiple Sclerosis and Chronic cerebro-spinal venous insufficiency. We included 769 patients with MS and CCSVI (299 males, 470 females) and 210 controls without ms and ccsvi (92 males, 118 females). each subject was investigated by echo-color-doppler (ecd). morphological and hemodynamic ecd data were recorded by a computerized mem-net maps of epidemiological national observatory on ccsvi and they were analyzed by mem-net clinical analysis programs. VCS of IJVs occurs in 240 subjects affected by CCSVI and MS (31% of total) and in 12 controls (6% of total). The differences between the two groups are statistical significant (X² = 36.64, pCerebro-Spinal Venous Insufficiency, Multiple Sclerosis, Venous Compression Syndrome.

Does compliance with amblyopia management improve following supervised occlusion treatment?

Science.gov (United States)

El-Ghrably, I A; Longville, D; Gnanaraj, L

2007-01-01

To demonstrate improvement in compliance following supervised occlusion therapy for amblyopia in children who had failed to respond to outpatient treatment. Retrospective review of the visual outcome of 30 children who were admitted to an ophthalmology ward for 1-day intensive supervised occlusion. These children had documented poor compliance and previously failed to respond to the outpatient occlusion treatment. During their stay a trained ophthalmology nurse educated parents regarding amblyopia and the benefits of occlusion therapy. Visual acuity (VA) of the amblyopic and fellow eyes was recorded on admission, discharge, and at each subsequent visit. The compliance was recorded from parent's history and also indirectly by noticing improvement in vision. The mean supervised occlusion was 7.4 hours (range 4-12 hours). The compliance with occlusion therapy improved in 23 children (77%) after discharge. The mean duration of occlusion after discharge improved to 4 hours (range 1-12 hours). The mean follow-up was 18 months (range 4-24 months). Though there was no dramatic improvement in VA at discharge there was a statistically significant improvement in VA between admission and last recorded VA (pocclusion following discharge, 21 (91%) gained at least one line of acuity in their amblyopic eye on the last assessment of their VA and five of them achieved 6/12. Of the seven children who did not comply with occlusion following discharge, only one patient gained one line improvement in his amblyopic eye. This study shows that supervised occlusion treatment and parental education was effective in children who had initially failed traditional outpatient treatment.

Balloon Occlusion of the Contralateral Iliac Artery to Assist Recanalization of the Ipsilateral Iliac Artery in Total Aortoiliac Occlusion: A Technical Note

Directory of Open Access Journals (Sweden)

Abdel Aziz A. Jaffan

2013-01-01

Full Text Available Endovascular recanalization of chronic total aortoiliac occlusion is technically challenging. Inability to reenter the true aortic lumen, following retrograde iliac recanalization, is one of the most common causes of failure. We describe a case of a total aortoiliac occlusion where balloon occlusion of the right common iliac artery, following its recanalization from a brachial approach, was used to facilitate antegrade recanalization of the occluded contralateral left common iliac artery.

A change in humidification system can eliminate endotracheal tube occlusion.

Science.gov (United States)

Doyle, Alex; Joshi, Manasi; Frank, Peter; Craven, Thomas; Moondi, Parvez; Young, Peter

2011-12-01

Inadequate airway humidification can result in endotracheal tube occlusion. There is evidence that heat and moisture exchangers (HMEs) are more prone to endotracheal tube occlusion than heated humidifiers (HHs) that contain a heated wire circuit. We aimed to compare the incidence of endotracheal tube occlusion while introducing a new dual-heated wire circuit HH in place of an established hydrophobic HME. This was a prospective observational study. All patients who required intubation were included in our analysis. Univariate statistical analysis was performed using a Fisher exact test. P humidification exclusively by HH. In the subsequent 18-month period, there were no further episodes of endotracheal tube occlusion. Our study demonstrates that there is a significant increase in the incidence of endotracheal tube occlusion when using a hydrophobic HME compared with an HH and that using a dual-heated wire circuit HH can eliminate endotracheal tube occlusion. Copyright © 2011 Elsevier Inc. All rights reserved.

Retinal vein occlusion: pathophysiology and treatment options

OpenAIRE

Karia, Niral

2010-01-01

Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

Local thrombolysis for patients of severe cerebral venous sinus thrombosis during puerperium

International Nuclear Information System (INIS)

Guo, Xin-bin; Fu, Zhenqiang; Song, Lai-jun; Guan, Sheng

2013-01-01

Objective: To explore and evaluate the efficacy of intrasinus thrombolysis (IST) in patients with cerebral venous sinus thrombosis (CVST) during postpartum period. Methods: 11 patients during postpartum period with CVST who received IST during July 2007–November 2011 were included. Urokinase was infused into the sinuses via a microcatheter. Magnetic resonance venography (MRV) was performed to assess the recanalization of venous sinuses. Results: Before discharge, the intracranial pressure in 11 patients was under 200 mmH 2 O. MRV confirmed that venous sinus of 9 patients were smooth. The cortex venous and deep venous recovered to normal. Venous sinus of 2 patients recanalized partly, and cortex venous and deep venous had compensation. 9 patients had good outcome and 2 patients had only mild deficits. Conclusion: Intrasinus thrombolysis is safe and effective in patients with severe cerebral venous sinus thrombosis during postpartum period

Clinical quality indicators of venous leg ulcers

DEFF Research Database (Denmark)

Kjaer, Monica L; Mainz, Jan; Soernsen, Lars T

2005-01-01

In the clinical setting, diagnosis and treatment of venous leg ulcers can vary considerably from patient to patient. The first step to reducing this variation is to document venous leg ulcer care through use of quantitative scientific documentation principles. This requires the development of val...

Risk factors for venous thromboembolism during pregnancy

DEFF Research Database (Denmark)

Jensen, Thomas Bo; Gerds, Thomas Alexander; Grøn, Randi

2013-01-01

Pregnant women are at an increased risk of venous thromboembolism (VTE). Risk factors for VTE among pregnant women are not sufficiently investigated.......Pregnant women are at an increased risk of venous thromboembolism (VTE). Risk factors for VTE among pregnant women are not sufficiently investigated....

[Single- and multi-unit fixed dental prostheses in relation to the occlusal system].

Science.gov (United States)

Witter, D J; Gerritsen, A E; van Spijker, A; Creugers, N H J

2013-02-01

Occlusion concepts based on functional aspects offer more solid ground in the diagnostic process and in the treatment of (reduced) dentitions than morphologically and mechanically oriented occlusion concepts. Nevertheless, for occlusal reconstruction morphologically oriented guidelines are necessary. These guidelines are based on the border movements and positions of the mandible in the orofacial system, and on the location and modelling of the occlusal contacts in the occlusal system. The modelling of single- and multi-unit fixed dental prostheses must harmonize with the occlusal system. Moreover, an important feature is the relation of the anterior teeth which enables mutually protected occlusion. Characteristics of a healthy orofacial and occlusal system are: absence of pathology, perceived sufficient oral functions, variability inform and function, and adaptive capacity. When designing single- or multiunit fixed dental prostheses, a pragmatic starting point is to maintain the existing occlusion and the existing speech pattern unless arguments can be provided for alterations. The occlusal design should aim at optimizing oral functions, such as mandibular and occlusal stability.

Acute pancreatitis during sickle cell vaso-occlusive painful crisis.

Science.gov (United States)

Ahmed, Shahid; Siddiqui, Anita K; Siddiqui, Rina K; Kimpo, Miriam; Russo, Linda; Mattana, Joseph

2003-07-01

Sickle cell disease is characterized by chronic hemolytic anemia and vaso-occlusive painful crisis. The vascular occlusion in sickle cell disease is a complex process and accounts for the majority of the clinical manifestations of the disease. Abdominal pain is an important component of vaso-occlusive painful crisis and may mimic diseases such as acute appendicitis and cholecystitis. Acute pancreatitis is rarely included as a cause of abdominal pain in patients with sickle cell disease. When it occurs it may result form biliary obstruction, but in other instances it might be a consequence of microvessel occlusion causing ischemia. In this series we describe four cases of acute pancreatitis in patients with sickle cell disease apparently due to microvascular occlusion and ischemic injury to the pancreas. All patients responded to conservative management. Acute pancreatitis should be considered in the differential diagnosis of abdominal pain in patients with sickle cell disease. Copyright 2003 Wiley-Liss, Inc.

Venous Return and Clinical Hemodynamics: How the Body Works during Acute Hemorrhage

Science.gov (United States)

Shen, Tao; Baker, Keith

2015-01-01

Venous return is a major determinant of cardiac output. Adjustments within the venous system are critical for maintaining venous pressure during loss in circulating volume. This article reviews two factors that are thought to enable the venous system to compensate during acute hemorrhage: 1) changes in venous elastance and 2) mobilization of…

Effect of elevated levels of coagulation factors on the risk of venous thrombosis in long-distance travelers

NARCIS (Netherlands)

Kuipers, Saskia; Cannegieter, Suzanne C.; Doggen, Catharina Jacoba Maria; Rosendaal, Frits R.

2009-01-01

Risk of venous thrombosis is increased after long-distance travel. Identifying high-risk groups may provide a basis for targeted prevention. We assessed the effect of increased levels of coagulation factors and combinations of risk factors in travelers in a large case-control study. We calculated

Occlusal designs on masticatory ability and patient satisfaction with complete denture: a systematic review.

Science.gov (United States)

Zhao, Ke; Mai, Qing-Qing; Wang, Xiao-Dong; Yang, Wen; Zhao, Li

2013-11-01

To systematically review clinical outcomes of different occlusal designs of complete dentures. Using a various key words, an electronic search of clinical trials published in English and Chinese literature was performed from four databases: Medline/PubMed, EMBASE, Cochrane Library, and CBM. Furthermore, a manual searching of the relevant journals and the bibliographies of reviews was performed. General satisfaction, masticatory ability, retention, and stability were major criteria for the evaluation of the outcomes. Studies met these criteria were selected for a full-text reading. The whole processes were performed by two reviewers independently. This systematic review started with 1030 articles, which were finally narrowed down to seven, according to the inclusion criteria. The following occlusal designs were included and analyzed: anatomic occlusion, balanced occlusion, canine guidance occlusion, lingualized occlusion, monoplane occlusion, and bilateral-balanced and canine-guided design. Three of the seven studies showed that lingualized occlusion had ratings of higher patients' satisfaction than other occlusion designs. On the other hand, the canine-guided occlusion dentures demonstrated equal or better clinical performances than bilateral-balanced dentures. Because of the heterogeneity and bias of the studies, it was not possible to analyze the data statistically. Lingualized occlusion and canine-guided occlusion can be successfully applied in the fabrication of complete dentures. Canine guided occlusion has also been shown to be satisfactory. More well-controlled randomized trials are needed regarding canine-guided occlusion and the relationship between alveolar ridge resorption, different occlusal schemes and patient satisfaction. The conventional prosthodontic wisdom that complete dentures require a balanced occlusal design is not supported by the included literature. A suitable occlusal scheme would be a critical factor for a successful complete denture

The correction of occlusal vertical dimension on tooth wear

Directory of Open Access Journals (Sweden)

Rostiny Rostiny

2007-12-01

Full Text Available The loss of occlusal vertical dimension which is caused by tooth wear is necessarily treated to regain vertical dimension. Correctional therapy should be done as early possible. In this case, simple and relatively low cost therapy was performed. In unserve loss of occlusal vertical dimension, partial removable denture could be used and the improvement of lengthening anterior teeth using composite resin to improve to regain vertical dimensional occlusion.

Gunther Tulip Inferior Vena Cava Filter Placement During Treatment for Deep Venous Thrombosis of the Lower Extremity

International Nuclear Information System (INIS)

Yamagami, Takuji; Kato, Takeharu; Iida, Shigeharu; Hirota, Tatsuya; Nishimura, Tsunehiko

2005-01-01

Purpose. To evaluate the efficacy and safety of Gunther tulip retrievable vena cava filter (GTF) implantation to prevent pulmonary embolism during intravenously administered thrombolytic and anticoagulation therapy and interventional radiological therapy for occlusive or nonocclusive deep venous thrombosis (DVT) of the lower extremity. Methods. We evaluated placement of 55 GTFs in 42 patients with lower extremity DVT who had undergone various treatments including those utilizing techniques of interventional radiology. Results. Worsening of pulmonary embolism in patients with existing pulmonary embolism or in those without pulmonary embolism at the time of GTF insertion was avoided in all patients. All attempts at implantation of the GTF were safely accomplished. Perforation and migration experienced by one patient was the only complication. Mean period of treatment for DVT under protection from pulmonary embolism by the GTF was 12.7 ± 8.3 days (mean ± SD, range 4-37 days). We attempted retrieval of GTFs in 18 patients in whom the venous thrombus had disappeared after therapy, and retrieval in one of these 18 cases failed. GTFs were left in the vena cava in 24 patients for permanent use when the DVT was refractory to treatment. Conclusion. The ability of the GTF to protect against pulmonary embolism during treatment of DVT was demonstrated. Safety in both placement and retrieval was clarified. Because replacement with a permanent filter was not required, use of the GTF was convenient when further protection from complicated pulmonary embolism was necessary

Mesenteric venous thrombosis after prolonged air travel-a case report

Directory of Open Access Journals (Sweden)

Joaquín Salas-Coronas

2014-07-01

Full Text Available We present a case of acute mesenteric venous thrombosis after a long distance flight in a traveller presenting with abdominal pain, diarrhoea and vomiting within 48 h of prolonged immobility situation. Venous thrombosis in the lower limbs and venous thromboembolism has been clearly associated with prolonged air travel (economy class syndrome. Thrombosis was diagnosed by computed tomography of the abdomen, and after starting anticoagulant therapy with acenocumarol, symptoms yielded completely in a few weeks. The study of thrombophilia was negative, although the existence of two first-degree relatives (mother and grandmother with a history of venous thrombosis with a history of venous thrombosis makes it likely a situation of inherited thrombophilia. Although exceptional, mesenteric venous thrombosis should be considered in travellers with acute abdominal pain after prolonged air travel when there are thrombophilic conditions.

Local thrombolysis for patients of severe cerebral venous sinus thrombosis during puerperium

Energy Technology Data Exchange (ETDEWEB)

Guo, Xin-bin, E-mail: gxb3906080@sina.com [Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, 1 Jianshe Road, Zhengzhou, 450052 (China); Fu, Zhenqiang, E-mail: fuzhenqiang1005@163.com [Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jianshe Road, Zhengzhou, 450052 (China); Song, Lai-jun, E-mail: laijunsong@sina.com [Department of Neurosurgery, The First Affiliated Hospital of Zhengzhou University, 1 Jianshe Road, Zhengzhou, 450052 (China); Guan, Sheng, E-mail: gsradio@126.com [Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, 1 Jianshe Road, Zhengzhou, 450052 (China)

2013-01-15

Objective: To explore and evaluate the efficacy of intrasinus thrombolysis (IST) in patients with cerebral venous sinus thrombosis (CVST) during postpartum period. Methods: 11 patients during postpartum period with CVST who received IST during July 2007–November 2011 were included. Urokinase was infused into the sinuses via a microcatheter. Magnetic resonance venography (MRV) was performed to assess the recanalization of venous sinuses. Results: Before discharge, the intracranial pressure in 11 patients was under 200 mmH{sub 2}O. MRV confirmed that venous sinus of 9 patients were smooth. The cortex venous and deep venous recovered to normal. Venous sinus of 2 patients recanalized partly, and cortex venous and deep venous had compensation. 9 patients had good outcome and 2 patients had only mild deficits. Conclusion: Intrasinus thrombolysis is safe and effective in patients with severe cerebral venous sinus thrombosis during postpartum period.

[Emphysematous gastritis with concomitant portal venous air].

Science.gov (United States)

Jeong, Min Yeong; Kim, Jin Il; Kim, Jae Young; Kim, Hyun Ho; Jo, Ik Hyun; Seo, Jae Hyun; Kim, Il Kyu; Cheung, Dae Young

2015-02-01

Emphysematous gastritis is a rare form of gastritis caused by infection of the stomach wall by gas forming bacteria. It is a very rare condition that carries a high mortality rate. Portal venous gas shadow represents elevation of intestinal luminal pressure which manifests as emphysematous gastritis or gastric emphysema. Literature reviews show that the mortality rate is especially high when portal venous gas shadow is present on CT scan. Until recently, the treatment of emphysematous gastritis has been immediate surgical intervention. However, there is a recent trend of avoiding surgery because of the frequent occurrence of post-operative complications such as anastomosis leakage. In addition, aggressive surgical treatment has failed to show significant improvement in prognosis. Recently, the authors experienced a case of emphysematous gastritis accompanied by portal venous gas which was treated successfully by conservative treatment without immediate surgical intervention. Herein, we present a case of emphysematous gastritis with concomitant portal venous air along with literature review.

[Venous thromboembolic disease: presentation of a case].

Science.gov (United States)

Mirpuri-Mirpuri, P G; Álvarez-Cordovés, M M; Pérez-Monje, A

2013-01-01

Venous thromboembolic disease in its clinical spectrum includes both deep vein thrombosis and pulmonary thromboembolism, which is usually a complication of deep vein thrombosis. It is a relatively common disease with significant morbidity and requires an accurate diagnosis. They are numerous risk factors for venous thromboembolism, and there is evidence that the risk of thromboembolic disease increases proportionally to the number of predisposing risk factors present. The primary care physician should know the risk factors and suspect the presence of venous thromboembolic disease when there is a compatible clnical picture. The treatment for this pathology is anticoagulation. We report a patient with cardiovascular risk factors who was seen with pain in the right leg and shortness of breath and referred to the hospital with suspected venous thromboembolism, atrial fibrillation and pleural effusion. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

Influence of occlusal contact area on cusp defection and stress distribution.

Science.gov (United States)

Costa, Anna Karina Figueiredo; Xavier, Thaty Aparecida; Paes-Junior, Tarcisio José Arruda; Andreatta-Filho, Oswaldo Daniel; Borges, Alexandre Luiz Souto

2014-11-01

The purpose of this study was to evaluate the effect of occlusal contact area for loading on the cuspal defection and stress distribution in a first premolar restored with a high elastic modulus restorative material. The Rhinoceros 4.0 software was used for modeling the three-dimensional geometries of dental and periodontal structures and the inlay restoration. Thus, two different models, intact and restored teeth with three occlusal contact areas, 0.1, 0.5 and 0.75 mm(2), on enamel at the occlusal surface of buccal and lingual cusps. Finite element analysis (FEA) was performed with the program ANSYS (Workbench 13.0), which generated a mesh with tetrahedral elements with greater refinement in the regions of interest, and was constrained at the bases of cortical and trabecular bone in all axis and loaded with 100 N normal to each contact area. To analysis of maximum principal stress, the smaller occlusal contact area showed greater compressive stress in region of load application for both the intact and inlay restored tooth. However, tensile stresses at the occlusal isthmus were similar for all three tested occlusal contact areas (60 MPa). To displacement of the cusps was higher for teeth with inlay (0.46-0.48 mm). For intact teeth, the smaller contact area showed greater displacement (0.10 mm). For teeth with inlays, the displacement of the cusps were similar in all types of occlusal area. Cuspal displacement was higher in the restored tooth when compared to the intact tooth, but there were no significant variations even with changes in the occlusal contact area. RELEVANCE CLINICAL: Occlusal contacts have a great influence on the positioning of teeth being able to maintain the position and stability of the mandible. Axial loads would be able to generate more uniform stress at the root presenting a greater concentration of load application in the point and the occlusal surface. Thus, is necessary to analyze the relationship between these occlusal contacts as dental

A concept to transfer a therapeutic splint position into permanent occlusion with a customized lingual appliance

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Sachse Tina

2012-05-01

Full Text Available Abstract Introduction The role of occlusion concerning temporomandibular disorder is still unclear but seems to be the only component of the stomathognathic system dentists are able to change morphologically. The aim of the paper is to describe the orthodontist’s approach for transferring and maintaining a therapeutic splint position into permanent occlusion using a fully customized lingual appliance. Methods Fixed acrylic bite planes on lower molars were used to maintain a symptom-free condyle position prior to orthodontic treatment. Silicone impressions of the arches including the fixed bite planes were used for the Incognito laboratory procedure. Two digital setups were made. One setup represents the target occlusion. A second setup including the bite planes was used to fabricate an additional set of lower molar brackets. In the leveling stage all teeth except the lower molars were settled to maintain the therapeutic condyle position. Finally, the fixed bite planes were stepwise removed and molar brackets were replaced to establish the permanent occlusion planned with the first setup. Results and discussion The advantage of an individual lingual appliance consists in the high level of congruence between the fabricated setups and the final clinical result. Both the individual scope for design and the precision of the appliance were vitally important in the treatment of a patient with a functional disorder of the masticatory system.

Pathophysiology of spontaneous venous gas embolism

Science.gov (United States)

Lambertsen, C. J.; Albertine, K. H.; Pisarello, J. B.; Flores, N. D.

1991-01-01

The use of controllable degrees and durations of continuous isobaric counterdiffusion venous gas embolism to investigate effects of venous gas embolism upon blood, cardiovascular, and respiratory gas exchange function, as well as pathological effects upon the lung and its microcirculation is discussed. Use of N2O/He counterdiffusion permitted performance of the pathophysiologic and pulmonary microstructural effects at one ATA without hyperbaric or hypobaric exposures.

Iliofemoral and iliocaval interventions in deep venous thrombosis

International Nuclear Information System (INIS)

Haage, P.; Guenther, R.W.

2005-01-01

Significant spontaneous thrombus disintegration in deep venous thrombosis (DVT) occurs very infrequently. On the contrary, these thrombi are prone to appositional growth and migration into the pulmonary arteries. The development of chronic venous insufficiency due to post-thrombotic syndrome is a frequent consequence of DVT. Therapeutic options in DVT include anticoagulation and recanalising procedures such as thrombolysis and thrombectomy. After appropriate indication assessment, the interventional radiologist can offer an efficacy-proven minimally-invasive vessel restitution approach by performing locoregional thrombolysis, pharmacomechanical therapy or, particularly in iliocaval thrombosis, mechanical thrombectomy. These methods not only serve to restitute of vessel patency, but also allow preserving venous valve function. In DVT with recurrent pulmonary embolism, retrievable filters with extended implantation duration can be deployed. In chronic proximal venous flow obstruction or in case of significant residual stenosis after thrombolysis, balloon angioplasty with stent implantation is the treatment modality of choice. Consequently, the radiologist can adopt an important role in the treatment of extensive venous disease. In this article, the treatment modalities concerning iliofemoral and iliocaval thrombosis are demonstrated and illustrated. (orig.)

[Characteristics of experimental occlusal interference-induced masticatory mechanical hyperalgesia of rats].

Science.gov (United States)

Li, Xuejiao; Cao, Ye; Xie, Qiufei

2014-10-01

To investigate the relationship between the existence of occlusal interference and masticatory muscle hyperalgesia by exploring the stimulus-response relationship between the duration of occlusal interference and masticatory muscle mechanical withdrawal threshold. Occlusal interference with 0.4 mm-thick crowns on rat molars was removed under anaesthesia at 2, 3, 4, 5, and 6 d after wear, and masticatory muscle mechanical withdrawal threshold was tested at 1, 3, 5, 7, 10, 14, 21 and 28 d. Decreased mechanical withdrawal thresholds were detected in temporal muscles and masseter muscles on both sides following occlusal interference (P 0.05). No significant differences were detected between the contralateral side with the ipsilateral side (P occlusal interference at 5 d, and the existence of the occlusal interference is positively correlated with the duration of the mechanical hyperalgesia.

Left atrial appendage occlusion

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Ahmad Mirdamadi

2013-01-01

Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

Emulsifiers' composition modulates venous irritation of the nanoemulsions as a lipophilic and venous irritant drug delivery system.

Science.gov (United States)

Mao, Chengwen; Wan, Jiangling; Chen, Huabing; Xu, Huibi; Yang, Xiangliang

2009-01-01

In this study, a nanoemulsion (NE) system was investigated for intravenous delivery of lipophilic and venous irritant drugs. NEs were prepared to deliver diallyl trisulfide (DT) for systemic therapy of bacterial and fungal infection, egg phospholipid was chosen as the main emulsifier, and two co-emulsifiers were also incorporated, including Poloxamer 188 (P188) and Solutol HS 15 (S15). Soybean oil was used as the dispersed phases, forming stable DT NEs with small particle sizes. The venous irritation of DT NEs was evaluated by in vitro human umbilical cord endothelial cells (CRL 1730) compatibility model with the intracellular adenosine triphosphate (ATP) and guanosine triphosphate (GTP) concentrations as the indices. The intracellular ATP and GTP reduction changed with the incorporation of a variety of co-emulsifiers, which varied in a free DT concentration-dependent manner. It was deduced that the free DT concentrations of NEs containing co-emulsifiers were determined by the partition coefficient of DT between oil and surfactant buffer solution. In conclusion, NE was an appropriate delivery system for lipophilic and venous irritant drug, and optimization of the composition of emulsifiers was an effective method to alleviate the venous irritation of DT NEs.

Design of the Monitored Occlusion Treatment of Amblyopia Study (MOTAS)

OpenAIRE

Stewart, C E; Fielder, A R; Stephens, D A; Moseley, M J

2002-01-01

Background/aims: The effectiveness of occlusion therapy for the treatment of amblyopia is a research priority. The authors describe the design of the Monitored Occlusion Treatment for Amblyopia Study (MOTAS) and its methodology. MOTAS will determine the dose-response relation for occlusion therapy as a function of age and category of amblyopia.

Systemic treatments for the prevention of venous thrombo-embolic events in paediatric cancer patients with tunnelled central venous catheters

NARCIS (Netherlands)

Schoot, Reineke A.; Kremer, Leontien C. M.; van de Wetering, Marianne D.; van Ommen, Cornelia H.

2013-01-01

Venous thrombo-embolic events (VTEs) occur in 2.2% to 14% of paediatric cancer patients and cause significant morbidity and mortality. The malignant disease itself, the cancer treatment and the presence of central venous catheters (CVCs) increase the risk of VTE. The primary objective of this review

Ocular neovascularization in eyes with a central retinal artery occlusion or a branch retinal artery occlusion

Directory of Open Access Journals (Sweden)

Mason lll JO

2015-06-01

Full Text Available John O Mason III,1,2 Shyam A Patel,1 Richard M Feist,1,2 Michael A Albert Jr,1,2 Carrie Huisingh,1 Gerald McGwin Jr,1,3 Martin L Thomley1,2 1Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, AL, USA; 2Retina Consultants of Alabama, Callahan Eye Foundation Hospital, Birmingham, AL, USA; 3Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA Purpose: To investigate the ocular neovascularization (ONV rate in eyes with a branch retinal artery occlusion (BRAO or a central retinal artery occlusion (CRAO, and to study factors that may influence the ONV rate secondary to CRAO.Methods: This was a retrospective case series of consecutive patients (286 total eyes: 83 CRAOs and 203 BRAOs who were diagnosed with a retinal artery occlusion from 1998 to 2013 at the Retina Consultants of Alabama and University of Alabama at Birmingham, Birmingham, AL, USA. Generalized estimating equations were used to evaluate the association between hypothesized risk factors and ONV development.Results: Twelve (14.5% of the 83 eyes with a CRAO developed ONV. Eleven of 12 eyes (91.7% had iris neovascularization, ten of 12 eyes (83.3% had neovascular glaucoma, and two of 12 eyes (16.7% had neovascularization of the optic disc. The average time for ONV development secondary to CRAO was 30.7 days, ranging from the date of presentation to 137 days. Only two (<1.0% of the 203 eyes with a BRAO developed iris neovascularization. Diabetes mellitus type 2 was a risk factor for ONV development following a CRAO with an adjusted odds ratio of 5.2 (95% confidence interval: 1.4–19.8 (P=0.02.Conclusion: ONV is an important complication of CRAO and is a less-frequent complication of BRAO. Patients with a CRAO, especially those with diabetes mellitus type 2, should be closely monitored for the first 6 months for ONV. Keywords: neovascularization, neovascular glaucoma, retinal artery occlusion, central

[The unnecessary application of central venous catheterization in surgical patients].

Science.gov (United States)

Uemura, Keiko; Inoue, Satoki; Kawaguchi, Masahiko

2018-04-06

Perioperative physicians occasionally encounter situations where central venous catheters placed preoperatively turn out to be unnecessary. The purpose of this retrospective study is to identify the unnecessary application of central venous catheter placement and determine the factors associated with the unnecessary application of central venous catheter placement. Using data from institutional perioperative central venous catheter surveillance, we analysed data from 1,141 patients who underwent central venous catheter placement. We reviewed the central venous catheter registry and medical charts and allocated registered patients into those with the proper or with unnecessary application of central venous catheter according to standard indications. Multivariate analysis was used to identify factors associated with the unnecessary application of central venous catheter placement. In 107 patients, representing 9.38% of the overall population, we identified the unnecessary application of central venous catheter placement. Multivariate analysis identified emergencies at night or on holidays (odds ratio [OR] 2.109, 95% confidence interval [95% CI] 1.021-4.359), low surgical risk (OR=1.729, 95% CI 1.038-2.881), short duration of anesthesia (OR=0.961/10min increase, 95% CI 0.945-0.979), and postoperative care outside of the intensive care unit (OR=2.197, 95% CI 1.402-3.441) all to be independently associated with the unnecessary application of catheterization. Complications related to central venous catheter placement when the procedure consequently turned out to be unnecessary were frequently observed (9/107) compared with when the procedure was necessary (40/1034) (p=0.032, OR=2.282, 95% CI 1.076-4.842). However, the subsequent multivariate logistic model did not hold this significant difference (p=0.0536, OR=2.115, 95% CI 0.988-4.526). More careful consideration for the application of central venous catheter is required in cases of emergency surgery at night or on

Cerebral venous angioma

International Nuclear Information System (INIS)

Inagawa, Tetsuji; Taguchi, Haruyoshi; Kamiya, Kazuko; Yano, Takashi; Nakajima, Reiko

1984-01-01

This report presents a 27-year-old male patient who was diagnosed as having cerebral venous angioma in the postero-temporal area by CT scan and cerebral angiography. The patient improved by removing angioma with electrocoagulation of medullary veins. (Namekawa, K.)

Extravasal occlusion of large vessels with titanic clips: efficiency, indications, and contraindications.

Science.gov (United States)

Vasilenko, Yu V; Kim, A I; Kotov, S A

2002-11-01

The mechanism of extravasal occlusion of blood vessels with titanic clips "Atrauclip" and "Ligaclip extra" was studied in order to reveal indications and contraindications to their use. Occlusion with the clips of both types was ineffective in vessels with a diameter of >7.0 mm. Arteritis or the presence of an intravascular occlusion facility in the vessel were also the contraindications for clip occlusion. In overcases the procedure of occlusion with titanic clips was efficient and atraumatic.

Treatment of hemobilia by transcatheter vascular occlusion

International Nuclear Information System (INIS)

Vaughan, R.; Roesch, J.; Keller, F.S.; Antonovic, R.; Veterans Administration Medical Center, Portland, OR

1984-01-01

Four cases of hemobilia treated by transcatheter arterial occlusion are presented and reviewed with 30 similar cases reported in the literature. Transcatheter vascular occlusion successfully controlled hemorrhage in all 34 patients. No obvious liver parenchymal damage appeared in 26 patients; transient elevation of liver enzymes occurred in 6 patients (18%) including one in our series; two of the patients reviewed died of acute hepatic insufficiency following nonselective hepatic artery embolization. Hemobilia should be considered when gastrointestinal hemorrhage occurs after abdominal trauma, liver biopsy or other manipulative liver procedures. Hepatic angiography establishes the diagnosis and selective vascular occlusion is the treatment of choice for control of intractable or recurrent hemorrhage. Techniques and precautions for the diagnosis and transcatheter therapy of hemobilia are discussed. (orig.)

Venous ulcers of the lower limb: Where do we stand?

Directory of Open Access Journals (Sweden)

Chatterjee S Sasanka

2012-01-01

Full Text Available Venous ulcers are the most common ulcers of the lower limb. It has a high morbidity and results in economic strain both at a personal and at a state level. Chronic venous hypertension either due to primary or secondary venous disease with perforator paucity, destruction or incompetence resulting in reflux is the underlying pathology, but inflammatory reactions mediated through leucocytes, platelet adhesion, formation of pericapillary fibrin cuff, growth factors and macromolecules trapped in tissue result in tissue hypoxia, cell death and ulceration. Duplex scan with colour flow is the most useful investigation for venous disease supplying information about patency, reflux, effects of proximal and distal compression, Valsalva maneuver and effects of muscle contraction. Most venous disease can be managed conservatively by leg elevation and compression bandaging. Drugs of proven benefit in venous disease are pentoxifylline and aspirin, but they work best in conjunction with compression therapy. Once ulceration is chronic or the patient does not respond to or cannot maintain conservative regime, surgical intervention treating the underlying venous hypertension and cover for the ulcer is necessary. The different modalities like sclerotherapy, ligation and stripping of superficial varicose veins, endoscopic subfascial perforator ligation, endovenous laser or radiofrequency ablation have similar long-term results, although short-term recovery is best with radiofrequency and foam sclerotherapy. For deep venous reflux, surgical modalities include repair of incompetent venous valves or transplant or transposition of a competent vein segment with normal valves to replace a post-thrombotic destroyed portion of the deep vein.

Mechanism of vaso-occlusion in sickle cell anemia

Science.gov (United States)

Lei, Huan; Karniadakis, George

2012-11-01

Vaso-occlusion crisis is one of the key hallmark of sickle cell anemia. While early studies suggested that the crisis is caused by blockage of a single elongated cell, recent experimental investigations indicate that vaso-occlusion is a complex process triggered by adhesive interactions among different cell groups in multiple stages. Based on dissipative particle dynamics, a multi-scale model for the sickle red blood cells (SS-RBCs), accounting for diversity in both shapes and cell rigidities, is developed to investigate the mechanism of vaso-occlusion crisis. Using this model, the adhesive dynamics of single SS-RBC was investigated in arterioles. Simulation results indicate that the different cell groups (deformable SS2 RBCs, rigid SS4 RBCs, leukocytes, etc.) exhibit heterogeneous adhesive behavior due to the different cell morphologies and membrane rigidities. We further simulate the tube flow of SS-RBC suspensions with different cell fractions. The more adhesive SS2 cells interact with the vascular endothelium and further trap rigid SS4 cells, resulting in vaso-occlusion in vessels less than 15 μm . Under inflammation, adherent leukocytes may also trap SS4 cells, resulting in vaso-occlusion in even larger vessels. This work was supported by the NSF grant CBET-0852948 and the NIH grant R01HL094270.

Role of contrast-enhanced MR venography in the preoperative evaluation of parasagittal meningiomas

Energy Technology Data Exchange (ETDEWEB)

Bozzao, Alessandro; Finocchi, Vanina; Romano, Andrea; Ferrante, Michele; Fasoli, Fabrizio; Fantozzi, Luigi Maria [S. Andrea Hospital, Neuroradiological Section, Rome (Italy); Trillo, Giuseppe; Ferrante, Luigi [S. Andrea Hospital, Neurosurgical Section, Rome (Italy)

2005-09-01

Parasagittal meningiomas (PSM) may pose a difficult surgical challenge since venous patency and collateral anastomoses have to be clearly defined for correct surgical planning. The aim of this study was to assess the diagnostic value of contrast-enhanced (CE) magnetic resonance venography (MRV) in the preoperative evaluation of venous infiltration and collateral venous anastomoses in patients with PSM. CE-MRV was compared with phase-contrast (PC) magnetic resonance (MR) angiography, conventional angiography (when available), and surgery as a reference. Twenty-three patients undergoing surgery for meningiomas located adjacent to the superior sagittal sinus were prospectively evaluated. All the patients underwent both conventional MR examination and MRV. This was performed by means of PC and CE techniques. Both sets of angiograms (CE and PC) were evaluated by two expert neuroradiologists to assess (1) patency of the sinus (patent/occluded), (2) the extent of occlusion (in centimeters), and (3) the number of collateral anastomoses close to the insertion of the meningioma. Eight patients underwent digital subtraction angiography (DSA). All patients were operated on, and intraoperative findings were taken as the gold standard to evaluate the diagnostic value of MRA techniques. PC-MRV showed a flow void inside the sinus compatible with its occlusion in 15 cases, whereas CE-MRV showed the sinus to be occluded in five cases. CE-MRV data were confirmed by surgery, showing five patients to have an occlusion of the superior sagittal sinus. The PC-MRV sensitivity was thus 100% with a specificity of 50%. In those cases in which both MRV techniques documented occlusion of the sinus, the extent of occlusion was overestimated by PC compared with CE and surgery. CE-MRV depicted 87% of collateral venous anastomoses close to the meningioma as subsequently confirmed by surgery, while PC showed 58%. In the preoperative planning for patients with meningiomas located close to a venous

Role of contrast-enhanced MR venography in the preoperative evaluation of parasagittal meningiomas

International Nuclear Information System (INIS)

Bozzao, Alessandro; Finocchi, Vanina; Romano, Andrea; Ferrante, Michele; Fasoli, Fabrizio; Fantozzi, Luigi Maria; Trillo, Giuseppe; Ferrante, Luigi

2005-01-01

Parasagittal meningiomas (PSM) may pose a difficult surgical challenge since venous patency and collateral anastomoses have to be clearly defined for correct surgical planning. The aim of this study was to assess the diagnostic value of contrast-enhanced (CE) magnetic resonance venography (MRV) in the preoperative evaluation of venous infiltration and collateral venous anastomoses in patients with PSM. CE-MRV was compared with phase-contrast (PC) magnetic resonance (MR) angiography, conventional angiography (when available), and surgery as a reference. Twenty-three patients undergoing surgery for meningiomas located adjacent to the superior sagittal sinus were prospectively evaluated. All the patients underwent both conventional MR examination and MRV. This was performed by means of PC and CE techniques. Both sets of angiograms (CE and PC) were evaluated by two expert neuroradiologists to assess (1) patency of the sinus (patent/occluded), (2) the extent of occlusion (in centimeters), and (3) the number of collateral anastomoses close to the insertion of the meningioma. Eight patients underwent digital subtraction angiography (DSA). All patients were operated on, and intraoperative findings were taken as the gold standard to evaluate the diagnostic value of MRA techniques. PC-MRV showed a flow void inside the sinus compatible with its occlusion in 15 cases, whereas CE-MRV showed the sinus to be occluded in five cases. CE-MRV data were confirmed by surgery, showing five patients to have an occlusion of the superior sagittal sinus. The PC-MRV sensitivity was thus 100% with a specificity of 50%. In those cases in which both MRV techniques documented occlusion of the sinus, the extent of occlusion was overestimated by PC compared with CE and surgery. CE-MRV depicted 87% of collateral venous anastomoses close to the meningioma as subsequently confirmed by surgery, while PC showed 58%. In the preoperative planning for patients with meningiomas located close to a venous

Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography

International Nuclear Information System (INIS)

Kim, Jae Duk; Kim, Jin Soo; You, Choong Hyun

2005-01-01

To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.

Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Duk; Kim, Jin Soo; You, Choong Hyun [Chosun University College of Medicine, Kwangju (Korea, Republic of)

2005-03-15

To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.

Arterial occlusive disease after radiotherapy

International Nuclear Information System (INIS)

Piedbois, P.; Mazeron, J.J.; Le Bourgeois, J.P.; Becquemin, J.P.; Blanc, I.; Lange, F.; Melliere, D.

1990-01-01

Fourteen cases of arterial occlusion or severe narrowing following radiotherapy are studied in order to assess the possible etiological role of such therapy in arterial lesion. Surgical results are also discussed in terms of long-term efficacy. The average time of occurrence after radiotherapy was 8 years post-radiotherapy. This series includes 7 supra-aortic trunk stenoses and 7 abdominal aorta trunk stenoses. The doses received in the volumes iradiated ranged from 47 to 70 Gy with standard fractionation. Association of atherosclerotic risk factors was present in 12 patients, but stenoses were usually confined to irradiated areas, and at imes occurred in uncommon sites. Surgical management included 11 by-passes, 2 endarterectomies and one percutaneous transluminal angioplasty. All patients experienced immediate and satisfactory functional improvements. Three patients were re-operated on because of the re-occlusion of the by-pass and graft infection. On the whole, stenoses in previously irradiated areas showed no particular difficulties for surgical treatment. It was concluded that radiotherapy seems to be a definite risk factor for arterial occlusion or narrowing, especially in association in association with atherosclerotic risk factors. (author). 45 refs.; 3 figs.; 2 tabs

Sealing Occlusal Dentin Caries in Permanent Molars

DEFF Research Database (Denmark)

Qvist, Vibeke; Borum, Mette Kit; Møller, Kirsten Dynes

2017-01-01

The purpose of this study was to investigate the possibility of postponing restorative intervention of manifest occlusal caries in young, permanent dentition by non-invasive sealing. This RCT-designed study included 521 occlusal lesions in 521 patients aged 6 to 17 y. Based on clinical and radiog......The purpose of this study was to investigate the possibility of postponing restorative intervention of manifest occlusal caries in young, permanent dentition by non-invasive sealing. This RCT-designed study included 521 occlusal lesions in 521 patients aged 6 to 17 y. Based on clinical...... longevity of sealings and restorations until retreatments, and 3) compare effectiveness of sealings and restorations to halt caries progression in sealed lesions and beneath restorations. Furthermore, we aimed to identify factors influencing longevity and the effectiveness of sealings and restorations.......001). The median survival time for sealings not replaced by restorations was 7.3 y (CI, 6.4 y to NA). Survival of sealings was increased in patients with low caries risk and/or excellent oral hygiene, second molars compared with first molars, and lesions not extending the middle one-third of the dentin. Survival...

Comorbidity in patients with branch retinal vein occlusion

DEFF Research Database (Denmark)

Bertelsen, Mette; Linneberg, Allan; Rosenberg, Thomas

2012-01-01

To evaluate comorbidity before and after the diagnosis of branch retinal vein occlusion to determine whether it is a consequence of arterial thickening and therefore could serve as a diagnostic marker for other comorbidities and to evaluate the risk factors for the development of such occlusion....

Occlusion-Aware Fragment-Based Tracking With Spatial-Temporal Consistency.

Science.gov (United States)

Sun, Chong; Wang, Dong; Lu, Huchuan

2016-08-01

In this paper, we present a robust tracking method by exploiting a fragment-based appearance model with consideration of both temporal continuity and discontinuity information. From the perspective of probability theory, the proposed tracking algorithm can be viewed as a two-stage optimization problem. In the first stage, by adopting the estimated occlusion state as a prior, the optimal state of the tracked object can be obtained by solving an optimization problem, where the objective function is designed based on the classification score, occlusion prior, and temporal continuity information. In the second stage, we propose a discriminative occlusion model, which exploits both foreground and background information to detect the possible occlusion, and also models the consistency of occlusion labels among different frames. In addition, a simple yet effective training strategy is introduced during the model training (and updating) process, with which the effects of spatial-temporal consistency are properly weighted. The proposed tracker is evaluated by using the recent benchmark data set, on which the results demonstrate that our tracker performs favorably against other state-of-the-art tracking algorithms.

In the absence of a central venous catheter, risk of venous thromboembolism is low in critically injured children, adolescents, and young adults: evidence from the National Trauma Data Bank.

Science.gov (United States)

O'Brien, Sarah H; Candrilli, Sean D

2011-05-01

To describe the incidence and risk factors of venous thromboembolism in a large sample of critical care pediatric, adolescent, and young adult trauma patients. The National Trauma Data Bank-the largest and most complete aggregation of trauma registry data in the United States. Seven hundred eighty-four level I to level IV trauma centers. Patients ≤ 21 yrs of age who spent at least 1 day in a critical care unit during a trauma admission between 2001 and 2005. To characterize differences between patients with and without venous thromboembolism, we extracted variables regarding patient demographics, injury pattern and severity, procedures, total length of stay, and intensive care unit and ventilator days. Odds ratios for predictors of venous thromboembolism were estimated with a logistic regression model. Among the 135,032 critical care patients analyzed, venous thromboembolism was uncommon (6 per 1,000 discharges). Placement of a central venous catheter was a significant predictor of venous thromboembolism (odds ratio = 2.24; p central venous catheter were of even greater magnitude, particularly in adolescents and young adults. The risk of venous thromboembolism in critical care patients without a central venous catheter was central venous access.

Anatomical features of venous outflow from rat’s reproductive organs

Directory of Open Access Journals (Sweden)

N. A. Nikitin

2012-01-01

Full Text Available The venous drainage from reproductive organs of rats is described; new data on peculiarities of the venous drainage are obtained.Objects of study were adult Wistar white rats (20 animals. The animals have passed precision dissection of vessels in order to study anatomic peculiarities of venous drainage from the left spermary in male rats and internal genital organs in female rats in norm. It has been shown that the venous drainage from the left spermary follows the spermatic vein entering into the pampiniform plexus system, which continues into the single venous trunk, which, in its turn, divides into the ascending and descending veins. The descending vein runs into the common left iliac vein, while the ascending vein runs into the renal vein. The venous drainage from female reproductive organs follows through the uterine vein, which, taking the tubal and spermatic veins, runs from the left into the left renal vein and from the right into the caudal vena cava.

Rendezvous technique for recanalization of long-segmental chronic total occlusion above the knee following unsuccessful standard angioplasty.

Science.gov (United States)

Cao, Jun; Lu, Hai-Tao; Wei, Li-Ming; Zhao, Jun-Gong; Zhu, Yue-Qi

2016-04-01

To assess the technical feasibility and efficacy of the rendezvous technique, a type of subintimal retrograde wiring, for the treatment of long-segmental chronic total occlusions above the knee following unsuccessful standard angioplasty. The rendezvous technique was attempted in eight limbs of eight patients with chronic total occlusions above the knee after standard angioplasty failed. The clinical symptoms and ankle-brachial index were compared before and after the procedure. At follow-up, pain relief, wound healing, limb salvage, and the presence of restenosis of the target vessels were evaluated. The rendezvous technique was performed successfully in seven patients (87.5%) and failed in one patient (12.5%). Foot pain improved in all seven patients who underwent successful treatment, with ankle-brachial indexes improving from 0.23 ± 0.13 before to 0.71 ± 0.09 after the procedure (P rendezvous technique is a feasible and effective treatment for chronic total occlusions above the knee when standard angioplasty fails. © The Author(s) 2015.

CT findings of middle cerebral artery occlusion

International Nuclear Information System (INIS)

Shiokawa, Yoshiaki; Saito, Isamu; Segawa, Hiromu; Fujimaki, Takamitsu; Tsutsumi, Kazuo

1987-01-01

In each case, we selected the CT scan showing the maximum extent of the low-density area (LDA) during the course of the occlusion and classified the findings into the following five types: basal ganglia type, extensive subcortical type, hemispheric type, branch type, and normal (no LDA) type. The angiographic occlusion sites of MCA were divided into 4 patterns; the origin of MCA, the distal M1 portion, MCA trifurcation, and one branch of the M2. The overall mortality rate was 33 %, while the morbidity rate was 53 %. The older the patient, the poorer the prognosis. In the 17 cases of MCA-origin occlusion, 12 cases (71 %) showed the basal ganglia type of LDA; their prognoses varied. In the 12 cases of MCA trifurcation occlusion, 10 cases (83 %) revealed an extensive subcortical type of LDA, and all showed a poor prognosis. In the MCA occlusion, the angiography-CT correlation seemed to depend on where and how the occlusion had occurred. Cerebral thrombosis frequently occurred at the origin of MCA, while cerebral embolism was more usually found to occlude the MCA trifurcation. In order to assess the collateral circulation quantitatively, we determined the IC-M2 time, that is, the conduction time of the contrast media from the intracranial carotid siphone (IC) to the insular portion of the MCA (M2) through the leptomeningeal anastomosis. Of the 29 cases admitted within 24 hours after the onset and which yet showed no LDA on the initial CT scan, all 13 cases with IC-M2 times of less than 5 seconds showed the basal ganglia type of LDA. On the other hand, the 16 cases with IC-M2 times of more than 5 seconds always demonstrated a large LDA, of either the extensive subcortical type or the hemispheric type. This IC-M2 time is useful in anticipating the extent of infarction before a CT scan demonstrates LDA and in predicting a patient's prognosis in the acute stage. (J.P.N.)

CT findings of middle cerebral artery occlusion

Energy Technology Data Exchange (ETDEWEB)

Shiokawa, Yoshiaki; Saito, Isamu; Segawa, Hiromu; Fujimaki, Takamitsu; Tsutsumi, Kazuo

1987-04-01

In each case, we selected the CT scan showing the maximum extent of the low-density area (LDA) during the course of the occlusion and classified the findings into the following five types: basal ganglia type, extensive subcortical type, hemispheric type, branch type, and normal (no LDA) type. The angiographic occlusion sites of MCA were divided into 4 patterns; the origin of MCA, the distal M1 portion, MCA trifurcation, and one branch of the M2. The overall mortality rate was 33 %, while the morbidity rate was 53 %. The older the patient, the poorer the prognosis. In the 17 cases of MCA-origin occlusion, 12 cases (71 %) showed the basal ganglia type of LDA; their prognoses varied. In the 12 cases of MCA trifurcation occlusion, 10 cases (83 %) revealed an extensive subcortical type of LDA, and all showed a poor prognosis. In the MCA occlusion, the angiography-CT correlation seemed to depend on where and how the occlusion had occurred. Cerebral thrombosis frequently occurred at the origin of MCA, while cerebral embolism was more usually found to occlude the MCA trifurcation. In order to assess the collateral circulation quantitatively, we determined the IC-M2 time, that is, the conduction time of the contrast media from the intracranial carotid siphone (IC) to the insular portion of the MCA (M2) through the leptomeningeal anastomosis. Of the 29 cases admitted within 24 hours after the onset and which yet showed no LDA on the initial CT scan, all 13 cases with IC-M2 times of less than 5 seconds showed the basal ganglia type of LDA. On the other hand, the 16 cases with IC-M2 times of more than 5 seconds always demonstrated a large LDA, of either the extensive subcortical type or the hemispheric type. This IC-M2 time is useful in anticipating the extent of infarction before a CT scan demonstrates LDA and in predicting a patient's prognosis in the acute stage. (J.P.N.).

Contribution of MRI in supracardiac total anomalous pulmonary venous drainage

International Nuclear Information System (INIS)

Kastler, B.; Germain, P.; Gangi, A.; Klinkert, A.; Dietemann, J.L.; Wackenheim, A.; Livolsi, A.; Willard, D.

1992-01-01

A case of supracardiac total anomalous pulmonary venous drainage (TAPVD) in an infant aged 2 1/2 months is presented. Diagnosis was established non invasively by magnetic resonance image (MRI). Not only did MRI precisely depict the anomalous venous pathway but it moreover securely excluded pulmonary venous obstruction. (orig.)

Occlusal accommodation and mouthguards for prevention of orofacial trauma.

Science.gov (United States)

Geary, Julian Lindsay; Clifford, Thomas Joseph; Kinirons, Martin James

2009-01-01

The aim of this study was to investigate the effect of two types of occlusal accommodation on the arch separation in centric and eccentric arch positions and to assess the opposing tooth contacts in professionally made, thermoformed sports mouthguards. Maxillary and mandibular alginate impressions, a wax interocclusal record of centric occlusion together with maxillary/condylar face-bow registrations, were recorded clinically for 10 undergraduate dental students who are sports activist volunteers of the School of Medicine and Dentistry, Queen's University Belfast. Two ethylene vinyl acetate thermoformed maxillary mouthguards were made for each player (N = 20) using a standardised procedure. Ten mouthguards served both as the control (i.e. the non-accommodated) group and also the accommodated, occlusally 'imprinted' group. The other 10 mouthguards served as the accommodated, occlusally 'ground' group. Casts were articulated, each non-accommodated and accommodated mouthguard was seated and the extent of the interocclusal opening was recorded in all three arch relationships. The number of mouthguard and mandibular tooth contacts were also recorded in each position. The increased vertical occlusal dimension that was found in the presence of non-accommodated mouthguards equated to the full-sheet thickness of the material that was used to form the mouthguards. Only mouthguards accommodated by grinding retained high levels of occlusal contact in all arch relationships that were tested. Within the limitations of this study, the modification of the occlusal surface made by flat grinding reduced the arch separation in eccentric movements and increased the opposing tooth contacts in custom-made mouthguards. This may contribute to increased comfort, compliance and the protective effect of these appliances thus resulting in a reduction of injuries to the teeth, arches and soft tissues.

Partial anomalous pulmonary venous return in Turner syndrome.

Science.gov (United States)

van den Hoven, Allard T; Chelu, Raluca G; Duijnhouwer, Anthonie L; Demulier, Laurent; Devos, Daniel; Nieman, Koen; Witsenburg, Maarten; van den Bosch, Annemien E; Loeys, Bart L; van Hagen, Iris M; Roos-Hesselink, Jolien W

2017-10-01

The aim of this study is to describe the prevalence, anatomy, associations and clinical impact of partial anomalous pulmonary venous return in patients with Turner syndrome. All Turner patients who presented at our Turner clinic, between January 2007 and October 2015 were included in this study and underwent ECG, echocardiography and advanced imaging such as cardiac magnetic resonance or computed tomography as part of their regular clinical workup. All imaging was re-evaluated and detailed anatomy was described. Partial anomalous pulmonary venous return was diagnosed in 24 (25%) out of 96 Turner patients included and 14 (58%) of these 24 partial anomalous pulmonary venous return had not been reported previously. Right atrial or ventricular dilatation was present in 11 (46%) of 24 partial anomalous pulmonary venous return patients. When studied with advanced imaging modalities and looked for with specific attention, PAPVR is found in 1 out of 4 Turner patients. Half of these patients had right atrial and/or ventricular dilatation. Evaluation of pulmonary venous return should be included in the standard protocol in all Turner patients. Copyright © 2017. Published by Elsevier B.V.

High dose urokinase for restoration of patency of occluded permanent central venous catheters in hemodialysis patients.

Science.gov (United States)

Shavit, L; Lifschitz, M; Plaksin, J; Grenader, T; Slotki, I

2010-10-01

Catheter thrombosis is common and results in inadequate dialysis treatment and, frequently, in catheter loss. Since dialysis treatment runs on a strict schedule, occluded catheters need to be restored in a timely and cost effective manner. We present a new shortened protocol of urokinase infusion that allows hemodialysis to be performed within 90 minutes. To chronic hemodialysis patients, who developed complete catheter occlusion, urokinase was infused simultaneously through both lumens of the catheter (125,000 units to each lumen) over 90 minutes. Technical success was defined as restoring blood pump speed to at least 250 ml/min. We determined the average time from catheter placement to first clot event (primary patency PP), recurrent clot event after urokinase treatment (secondary patency SP), catheter salvage rate and cause for removal. 37 catheters developed total thrombosis and urokinase was used to restore patency one or more times (total 47 treatments). Catheter salvage rate was 97 %. The average time of PP was 152 ± 56 days (7 - 784 days). Nine patients (30%) developed recurrent occlusion and the average time of SP was 64 ± 34 days (2 - 364 days). One catheter was removed because of dysfunction due to thrombosis. Other catheters were removed due to infection, fistula maturation or fell out spontaneously. Hemodialysis was performed immediately after treatment with blood speed of 250 ml/min in all patients. Our protocol is highly effective, short, and allows to restore patency of totally occluded central venous catheters with minimal disruption of the dialysis session.

Occlusion-amblyopia following high dose oral levodopa combined with part time patching

OpenAIRE

Mihir Kothari

2014-01-01

Part time occlusion therapy is not reported to cause occlusion (reverse) amblyopia. However, when combined with high dose oral levodopa, an increase in the plasticity of the visual cortex can lead to occlusion amblyopia. In this case report, we describe a six year old child who developed occlusion amblyopia following part time patching combined with oral levodopa.

Occlusion-amblyopia following high dose oral levodopa combined with part time patching.

Science.gov (United States)

Kothari, Mihir

2014-12-01

Part time occlusion therapy is not reported to cause occlusion (reverse) amblyopia. However, when combined with high dose oral levodopa, an increase in the plasticity of the visual cortex can lead to occlusion amblyopia. In this case report, we describe a six year old child who developed occlusion amblyopia following part time patching combined with oral levodopa.

Shape tracking with occlusions via coarse-to-fine region-based sobolev descent

KAUST Repository

Yang, Yanchao

2015-05-01

We present a method to track the shape of an object from video. The method uses a joint shape and appearance model of the object, which is propagated to match shape and radiance in subsequent frames, determining object shape. Self-occlusions and dis-occlusions of the object from camera and object motion pose difficulties to joint shape and appearance models in tracking. They are unable to adapt to new shape and appearance information, leading to inaccurate shape detection. In this work, we model self-occlusions and dis-occlusions in a joint shape and appearance tracking framework. Self-occlusions and the warp to propagate the model are coupled, thus we formulate a joint optimization problem. We derive a coarse-to-fine optimization method, advantageous in tracking, that initially perturbs the model by coarse perturbations before transitioning to finer-scale perturbations seamlessly. This coarse-to-fine behavior is automatically induced by gradient descent on a novel infinite-dimensional Riemannian manifold that we introduce. The manifold consists of planar parameterized regions, and the metric that we introduce is a novel Sobolev metric. Experiments on video exhibiting occlusions/dis-occlusions, complex radiance and background show that occlusion/dis-occlusion modeling leads to superior shape accuracy. © 2014 IEEE.

Identification and adjustment of experimental occlusal interference using functional magnetic resonance imaging.

Science.gov (United States)

Oda, Masafumi; Yoshino, Kenichi; Tanaka, Tatsurou; Shiiba, Shunji; Makihara, Eri; Miyamoto, Ikuya; Nogami, Shinnosuke; Kito, Shinji; Wakasugi-Sato, Nao; Matsumoto-Takeda, Shinobu; Nishimura, Shun; Murakami, Keita; Koga, Masahiro; Kawagishi, Shigenori; Yoshioka, Izumi; Masumi, Shin-Ichi; Kimura, Mitsutaka; Morimoto, Yasuhiro

2014-10-10

The purpose of this study was to use functional magnetic resonance imaging (fMRI) to quantify changes in brain activity during experimental occlusal interference. Fourteen healthy volunteers performed a rhythmical tapping occlusion task with experimental occlusal interference of the right molar tooth at 0 mm (no occlusion), 0.5 mm, and 0.75 mm. The blood-oxygen-level dependent (BOLD) signal was quantified using statistical parametric mapping and compared between rest periods and task periods. In tapping tasks with experimental occlusal interference of 0.75 mm or 0.5 mm, there was clear activation of the contralateral teeth-related primary sensory cortex and Brodmann's area 46. At 0 and 30 minutes after removal of the experimental occlusal interference, the activation clearly appeared in the bilateral teeth-related primary sensory cortices and Brodmann's area 46. At 60 minutes after the removal of the experimental occlusal interference, the activation of Brodmann's area 46 had disappeared, and only the bilateral teeth-related primary sensory cortices were active. The present results suggest that adjustments for experimental occlusal interference can be objectively evaluated using fMRI. We expect that this method of evaluating adjustments in occlusal interference, combined with fMRI and the tapping task, could be applied clinically in the future.

Pharmacological prevention of rocuronium-induced injection pain or withdrawal movements: a meta-analysis.

Science.gov (United States)

Kwak, Hyun Jeong; Kim, Ji Young; Kim, Yong Beom; Min, Sang Kee; Moon, Bong Ki; Kim, Jong Yeop

2013-10-01

Rocuronium is reported to be associated with injection pain or withdrawal movement (IPWM). This meta-analysis assessed the efficacy of different pharmacological treatments used to decrease the incidence of the rocuronium-induced IPWM. We searched the Cochrane Library, Embase and PubMed for randomized controlled trials comparing a pharmacological drug with a placebo to prevent the rocuronium-induced IPWM and found 37 studies with 5,595 patients. Overall incidence of rocuronium-induced IPWM was 74%. Pretreatment with opioids [risk ratio (RR) 0.16; 95% confidence interval (95% CI) 0.09-0.29], lidocaine (0.47; 0.35-0.64), and ketamine (0.41; 0.22-0.77) were effective in decreasing IPWM. Lidocaine pretreatment with venous occlusion (0.40; 0.32-0.49) and opioids pretreatment with venous occlusion (0.77; 0.61-0.96) were also effective. Mixing sodium bicarbonate (NaHCO3) with rocuronium (0.15; 0.06-0.34) was also efficacious in reducing IPWM. Indirect comparison shows that the RR of NaHCO3 admixture and pretreatment with opioids were lower than that of the other four interventions (pretreatments of ketamine or lidocaine, and lidocaine or opioids with venous occlusion). This meta-analysis suggests that opioids, lidocaine, ketamine, and NaHCO3 are effective in decreasing rocuronium-induced IPWM. Considering the efficacy and convenience, pretreatment with opioids without venous occlusion is recommended for reducing rocuronium-induced IPWM.

A survey of current practice of vascular surgeons in venous disease management.

Science.gov (United States)

Bush, Ruth L; Gloviczki, Peter

2013-01-01

Acute venous thromboembolism and chronic venous diseases are common conditions that affect a large proportion of the United States population. The diagnosis of venous disease has improved, and the treatment options have rapidly evolved over the past decade. To date, it is unclear to what extent vascular surgeons have become involved in the modern management of venous disorders. This survey was undertaken to explore the current interest and practice of vascular surgeons in the contemporary care of venous disease. A survey was administered via a web-based platform to active and candidate members of the Society for Vascular Surgery (SVS). The survey included 30 questions investigating the characteristics of venous surgeons and scope of venous practice. Open-ended questions were also included for commentary. A total of 1879 surveys were sent to SVS members nationwide, and 385 members participated (response rate of 20.5%). The participants were mostly men (89.6%) with 37.7% practicing in an academic setting and 59.2% in private practice. The respondents treated superficial veins (92.9%) and deep veins (85.8%) in clinical practice, with 89.9% having their own vascular laboratory. A wide spectrum of interventions for superficial (91.9%), deep (85.8%), and perforator veins (52.7% endovenous, 19.4% subfascial endoscopic perforator surgery) are being performed by respondents. Only 26.2% had learned endovenous thermal ablation in their training program; however, over 96% of those performing venous interventions utilized this technique. Overall, the majority (85.5%) devoted 50% or less of practice to venous disorders. Respondents indicated that limitations to expansion of vein practices mainly involved challenges with third party payers, local competition, and existing large volumes of arterial interventions needing to be performed. Despite the widespread incorporation of venous disease into current vascular practices, 66.1% are not members of the American Venous Forum (AVF

[Superficial venous thrombosis. A state of art].

Science.gov (United States)

Sándor, Tamás

2017-01-01

For a long time superficial thrombophlebitis has been thought to be a rather benign condition. Recently, when duplex ultrasound technique is used for the diagnosis more and more often, the disease is proved to be more dangerous than anticipated. Thrombosis propagates to the deep veins in 6-44% and pulmonary embolism was observed on the patients in 1,5-33%. We can calculate venous thromboembolic complications on every fourth patient. Diagnosis is clinical, but duplex ultrasound examination is mandatory, for estimation of the thrombus extent, for exclusion of the deep venous thrombosis and for follow up. Both legs should be checked with ultrasound, because simultaneous deep venous thrombosis can develop on the contralateral limb. Two different forms can be distinguished: superficial venous thrombosis with, or without varicose veins. In cases of spontaneous, non varicous form, especially when the process is migrating or recurrent, a careful clinical examination is necessery for exclusion of malignant diseases and thrombophilia. The treatment options are summarised on the basis of recent international consensus statements. The American and German guidelines are similar. Compression and mobilisation are cornerstones of the therapy. For a short segment thrombosis non steroidal antiinflammatory drugs are effective. For longer segments low molecular-weight heparins are preferred. Information on the effect of the novel oral anticoagulants for the therapy is lacking but they may appear to be effective in the future for this indication. When thrombus is close to the sapheno-femoral or sapheno-popliteal junction crossectomy (high ligation), or low molecular-weight heparin in therapeutic doses are indicated. The term superficial thrombophlebitis should be discouraged, because inflammation and infection is not the primary pathology. It should be called correctly superficial venous thrombosis in order to avoid the unnecessary administration of antibiotics and the misconception

Guideline for the management of wounds in patients with lower-extremity venous disease: an executive summary.

Science.gov (United States)

Kelechi, Teresa J; Johnson, Jan J

2012-01-01

This article provides an executive summary of the lower extremity venous disease (LEVD) evidence-based guideline produced by the WOCN Wound Guidelines Task Force. The target audience for this guideline is health care professionals who specialize in, direct, or provide wound care for patients at risk for or with lower-extremity venous disease. The full guideline opens with an overview of definitions of LEVD, its prevalence, clinical relevance, etiology, related physiology and pathophysiology, and overall management goals for patients at risk for developing venous leg ulcers. A detailed assessment section describes how to conduct a full clinical history and physical examination. Two approaches to interventions are provided: one addresses prevention strategies to reduce the risk of developing LEVD with ulcers. Methods to prevent ulcer recurrence are summarized including compression therapy, adjunctive therapies, medications, and patient education. A second approach presents treatment interventions including wound cleansing, debridement, infection control, antibiotic use, along with management of the periwound skin, nutrition, pain, and edema. This section also discusses limb elevation, surgical options, adjunctive therapies, patient education, and health care provider follow-up. A comprehensive reference list, glossary of terms, and appendices on cellulitis and venous eczema, types of edema, and compression therapy are available at the end of the guideline. This article provides an executive summary of the essential features of the guideline.

Relationships between duplex findings and quality of life in long-term follow-up of patients treated for chronic venous disease.

Science.gov (United States)

Huang, Ying; Gloviczki, Peter

2016-03-01

Relationships between duplex findings and data on health-related quality of life (QoL) to assess long-term results of treatment of varicose veins and chronic venous insufficiency (CVI) are not well known. The goal of this review was to correlate duplex findings and QoL assessments in clinical studies with long-term follow-up. A review of the English language literature on PUBMED revealed 17 clinical studies, including 9 randomized controlled trials (RCTs), 6 prospective, and 2 retrospective studies that included patients with at least 5-year follow-up after endovenous laser ablation (EVLA), radiofrequency ablation (RFA), ultrasound-guided foam sclerotherapy (UGFS), and traditional superficial venous surgery. At 5 years, great saphenous vein (GSV) occlusion rate on duplex ultrasound ranged from 66% to 82% for EVLA, from 62% to 92% for RFA, from 41% to 58% for UGFS and from 54% to 85% for surgery. Freedom from GSV reflux rates were 82% and 84%, respectively for EVLA and surgery, and ranged between 84% and 95% for RFA. Significant improvements were observed in several domains of generic QoL and in most domains of venous disease-specific QoL, irrespective of the treatment. In at least one RCT, CIVIQ scores correlated well with abnormal duplex findings in patients who underwent treatment with UGFS. In another RCT, long-term AVVQ was significantly better after surgery as compared with UGFS similar to results of duplex findings. Analysis of the available literature confirmed that all four techniques were effective in the abolishment of reflux or obliteration of the GSV. Moreover, well-designed RCTs with large sample size are needed to produce robust long-term data on clinical outcome after treatment of varicose veins and CVI and to better understand the relationships between duplex-derived data and QoL assessments. © The Author(s) 2016.

Carotid near-occlusion frequently has high peak systolic velocity on Doppler ultrasound

Energy Technology Data Exchange (ETDEWEB)

Khangure, Simon R.; Machnowska, Matylda; Fox, Allan J.; Hojjat, Seyed-Parsa; Aviv, Richard I. [Sunnybrook Health Sciences Centre, Department of Medical Imaging, Neuroradiology Division, Toronto, ON (Canada); University of Toronto, Department of Medical Imaging, Division of Neuroimaging, Toronto (Canada); Benhabib, Hadas [Sunnybrook Health Sciences Centre, Department of Medical Imaging, Neuroradiology Division, Toronto, ON (Canada); Groenlund, Christer [Umeaa University, Department of Radiation Sciences, Biomedical Engineering, Umeaa (Sweden); Herod, Wendy [Department of Surgery, Sunnybrook Health Sciences Centre, Toronto (Canada); Maggisano, Robert [Department of Surgery, Sunnybrook Health Sciences Centre, Toronto (Canada); University of Toronto, Division of Vascular Surgery, Department of Surgery, Toronto (Canada); Sjoeberg, Anders [Umeaa University, Department of Radiation Sciences, Biomedical Engineering, Umeaa (Sweden); Umeaa University, Department of Pharmacology and Clinical Neuroscience, Umeaa (Sweden); Wester, Per [Umeaa University, Department of Public Health and Clinical Medicine, Umeaa (Sweden); Karolinska Institutet Danderyds Hospital, Department of Clinical Sciences, Stockholm (Sweden); Hopyan, Julia [University of Toronto, Division of Neurology, Department of Medicine, Toronto (Canada); Johansson, Elias [Umeaa University, Department of Pharmacology and Clinical Neuroscience, Umeaa (Sweden); Umeaa University, Department of Public Health and Clinical Medicine, Umeaa (Sweden)

2018-01-15

Carotid near-occlusion is a tight atherosclerotic stenosis of the internal carotid artery (ICA) resulting in decrease in diameter of the vessel lumen distal to the stenosis. Near-occlusions can be classified as with or without full collapse, and may have high peak systolic velocity (PSV) across the stenosis, mimicking conventional > 50% carotid artery stenosis. We aimed to determine how frequently near-occlusions have high PSV in the stenosis and determine how accurately carotid Doppler ultrasound can distinguish high-velocity near-occlusion from conventional stenosis. Included patients had near-occlusion or conventional stenosis with carotid ultrasound and CT angiogram (CTA) performed within 30 days of each other. CTA examinations were analyzed by two blinded expert readers. Velocities in the internal and common carotid arteries were recorded. Mean velocity, pulsatility index, and ratios were calculated, giving 12 Doppler parameters for analysis. Of 136 patients, 82 had conventional stenosis and 54 had near-occlusion on CTA. Of near-occlusions, 40 (74%) had high PSV (≥ 125 cm/s) across the stenosis. Ten Doppler parameters significantly differed between conventional stenosis and high-velocity near-occlusion groups. However, no parameter was highly sensitive and specific to separate the groups. Near-occlusions frequently have high PSV across the stenosis, particularly those without full collapse. Carotid Doppler ultrasound does not seem able to distinguish conventional stenosis from high-velocity near-occlusion. These findings question the use of ultrasound alone for preoperative imaging evaluation. (orig.)

Object tracking by occlusion detection via structured sparse learning

KAUST Repository

Zhang, Tianzhu; Ghanem, Bernard; Xu, Changsheng; Ahuja, Narendra

2013-01-01

occlusion through structured sparse learning. We test our tracker on challenging benchmark sequences, such as sports videos, which involve heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that our tracker

Robust 3D Face Recognition in the Presence of Realistic Occlusions

NARCIS (Netherlands)

Alyuz, Nese; Gökberk, B.; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.; Akarun, Lale

2012-01-01

Facial occlusions pose significant problems for automatic face recognition systems. In this work, we propose a novel occlusion-resistant three-dimensional (3D) facial identification system. We show that, under extreme occlusions due to hair, hands, and eyeglasses, typical 3D face recognition systems

Venous function after pharmacomechanical thrombolysis for extensive iliofemoral deep vein thrombosis

Directory of Open Access Journals (Sweden)

Wim Greeff

2017-08-01

Full Text Available Background: Chronic venous insufficiency is an important complication following iliofemoral deep venous thrombosis. Early thrombus removal may preserve venous function and prevent this complication. This study represents the largest reported South African series of pharmacomechanical thrombolysis for iliofemoral deep venous thrombosis to date. Objective: To evaluate the long-term outcome following pharmacomechanical thrombolysis for proximal and extensive deep venous thrombosis in a private, specialist vascular unit. Methods: All patients who underwent pharmacomechanical thrombolysis for iliofemoral deep venous thrombosis between August 2009 and January 2016 were invited to return for clinical assessment and venous ultrasound. Clinical findings were recorded according to the Villalta score and clinical, etiology, anatomic and pathology (CEAP classification. The quality of life (QoL was assessed utilising the VEINES-QoL/Sym questionnaire, providing two scores per patient, one describing the QoL and the other symptom severity (Sym. Results: Thirty two patients (35 legs were evaluated. There were 25 females and 7 males, with a mean age of 33.5 years (±14 years. The mean follow-up period was 31 months (range 3 months – 80 months. Results of the CEAP classification were C0 = 24 (75%, C1 = 1 (4%, C2 = 2 (6%, C3 = 2 (6% and C4 = 3 (9%. Thirty-one (97% patients had Villalta scores from 0 to 4, indicating no or mild evidence of venous disease. One patient (3% had a Villalta score of 6, indicating post-thrombotic syndrome. The mean QoL score was 87% (±12 and the mean Sym score was 86% (±14. Twenty-four (75% patients had no abnormality on ultrasound, with fibrosis the most observed abnormality. Conclusion: Most patients who had undergone pharmacomechanical thrombolysis for extensive iliofemoral deep venous thrombosis showed few significant clinical signs of chronic venous insufficiency, had excellent function on venous ultrasound and reported

Discordant relationship between Essure microinsert position and tubal occlusion.

Science.gov (United States)

Hou, Melody Y

2016-07-27

Hysteroscopic sterilisation with Essure requires confirmation of tubal occlusion by hysterosalpingogram or microinsert position by transvaginal sonography 3 months after placement before women can rely on the method for pregnancy prevention. A 39-year-old woman underwent hysteroscopic sterilisation via Essure, with successful bilateral tubal occlusion documented on hysterosalpingogram. She had a subsequent unintended pregnancy and termination, and presented with persistent pelvic pain and other non-specific symptoms. She underwent a laparoscopic-assisted vaginal hysterectomy with bilateral salpingectomy, with complete resolution of her symptoms. Pathological evaluation demonstrated a perforated Essure microinsert and ipsilateral tubal occlusion, and a correctly placed Essure microinsert with ipsilateral tubal patency. Clinicians should be cautious about the assumption that correctly placed microinserts based on ultrasonography, hysterosalpingogram or laparoscopic evaluation assures occlusion success. 2016 BMJ Publishing Group Ltd.

Adaptive Self-Occlusion Behavior Recognition Based on pLSA

Directory of Open Access Journals (Sweden)

Hong-bin Tu

2013-01-01

Full Text Available Human action recognition is an important area of human action recognition research. Focusing on the problem of self-occlusion in the field of human action recognition, a new adaptive occlusion state behavior recognition approach was presented based on Markov random field and probabilistic Latent Semantic Analysis (pLSA. Firstly, the Markov random field was used to represent the occlusion relationship between human body parts in terms an occlusion state variable by phase space obtained. Then, we proposed a hierarchical area variety model. Finally, we use the topic model of pLSA to recognize the human behavior. Experiments were performed on the KTH, Weizmann, and Humaneva dataset to test and evaluate the proposed method. The compared experiment results showed that what the proposed method can achieve was more effective than the compared methods.

The Essentials of Parathyroid Hormone Venous Sampling

Energy Technology Data Exchange (ETDEWEB)

Taslakian, Bedros, E-mail: btaslakian@gmail.com [NYU Langone Medical Center, Department of Radiology, NYU School of Medicine (United States); Trerotola, Scott O., E-mail: streroto@uphs.upenn.edu [Perelman School of Medicine of the University of Pennsylvania, Department of Radiology (United States); Sacks, Barry, E-mail: bsacks@bidmc.harvard.edu [Beth Israel Deaconess Medical Center, Department of Interventional Radiology (United States); Oklu, Rahmi, E-mail: oklu.rahmi@mayo.edu [Mayo Clinic, Department of Interventional Radiology (United States); Deipolyi, Amy, E-mail: deipolya@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States)

2017-01-15

Hyperparathyroidism is an excess of parathyroid hormone in the blood due to over-activity of one or more parathyroid gland. Localization of abnormal glands with noninvasive imaging modalities, such as technetium sestamibi scan and cross-sectional imaging, has a high success rate. Parathyroid venous sampling is performed for patients with persistent or recurrent disease after previous parathyroid surgery, when repeat noninvasive imaging studies are negative or discordant. The success of invasive localization studies and results interpretation is dependent on the interventional radiologist’s understanding of the normal and ectopic anatomic locations of parathyroid glands, as well as their blood supply and venous drainage. Anatomic and technical considerations for selective parathyroid venous sampling are reviewed.

MRI in venous thromboembolic disease

International Nuclear Information System (INIS)

Sostman, H.D.; Debatin, J.F.; Spritzer, C.E.; Coleman, R.E.; Grist, T.M.; MacFall, J.R.

1993-01-01

We evaluated the ability of magnetic resonance (MR) imaging to detect deep venous thrombosis (DVT) and pulmonary embolism (PE). MR venography was performed on 217 patients suspected of having DVT. Cine-MR imaging of the pulmonary arteries was performed in 14 other patients who were thought to have PE based on other imaging studies. In a third group of 5 patients, MR pulmonary angiograms were performed in the sagittal and coronal planes with a multislice fast gradient recalled echo technique. All but one of the 217 MR venograms were technically adequate. In 72 patients with correlative imaging studies (venography and ultrasound) MR venography was 99% sensitive and 95% specific. On the basis of follow-up (mean 8.3 months), no false-negative MR venograms were detected in an additional 64 patients. In 11 other patients MR revealed a diagnosis other than DVT. Cine-MR showed PE in all 14 patients evaluated. MR pulmonary arteriography demonstrated filling defects consistent with acute PE in 2 of 3 patients with acute PE; in the third patient only a questionable filling defect was seen. Coarctations or webs were found in the pulmonary arteries of both patients with chronic PE. These preliminary data suggest that MR imaging may be able to evaluate both the peripheral venous and the pulmonary arterial component of venous thromboembolic disease. Further technical refinement and more extensive clinical experience will be required to establish the role of this method in diagnosing pulmonary embolism, but MR venography is now used routinely in our hospital for the diagnosis of deep venous thrombosis. (orig.)

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

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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.

Comparison of vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification systems.

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Han, Young Keun; Miller, Kevin M

2009-08-01

To compare vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification machines. Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. The vacuum rise time under normal and enhanced aspiration modes, vacuum limit accuracy, and occlusion break surge of the Infiniti Vision System, Stellaris Vision Enhancement System, and WhiteStar Signature Phacoemulsification System were tested. Vacuum rise time and limit accuracy were measured at limit settings of 400 mm Hg and 600 mm Hg. Surge area was recorded at vacuum limit settings of 200 mm Hg, 300 mm Hg, 400 mm Hg, and 500 mm Hg. The Infiniti had the fastest vacuum rise times under normal and enhanced aspiration modes. At 4 seconds, the vacuum limit accuracy was greatest with the Infiniti at the 400 mm Hg limit and the Signature at the 600 mm Hg limit. The Stellaris did not reach either vacuum target. The Infiniti performed better than the other 2 machines during testing of occlusion break surge at all vacuum limit settings above 200 mm Hg. Under controlled laboratory test conditions, the Infiniti had the fastest vacuum rise time, greatest vacuum limit accuracy at 400 mm Hg, and least occlusion break surge. These results can be explained by the lower compliance of the Infiniti system.

Occlusion-amblyopia following high dose oral levodopa combined with part time patching

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Mihir Kothari

2014-01-01

Full Text Available Part time occlusion therapy is not reported to cause occlusion (reverse amblyopia. However, when combined with high dose oral levodopa, an increase in the plasticity of the visual cortex can lead to occlusion amblyopia. In this case report, we describe a six year old child who developed occlusion amblyopia following part time patching combined with oral levodopa.

Fish Intake and Venous Thromboembolism: A Systematic Literature Review.

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Mattiuzzi, Camilla; Cervellin, Gianfranco; Franchini, Massimo; Lippi, Giuseppe

2016-05-01

Diet plays an important role in modulating the risk of arterial and venous thrombosis. Several lines of evidence attest that consumption of fish and its compounds, especially omega-3 fatty acids, may be effective to decrease the cardiovascular risk. Since the pathogenesis of arterial and venous thrombosis share some common aspects, we performed a systematic review of published clinical studies that investigated the association between fish intake and venous thrombosis. An electronic search was carried out in Medline, Scopus, and ISI Web of Science using the key words "fish" OR "seafood" AND "venous thromboembolism" OR "deep vein thrombosis" OR "pulmonary embolism", with no language or date restriction. Overall, 6 studies (5 prospective and 1 case-control) were finally identified. In only 1 small case-control study, a larger intake of total fish was found to be negatively associated with the risk of venous thromboembolism. No association was found in 4 large prospective studies, whereas a positive association was observed in the remaining. No substantial difference was also noticed between intake of fatty or lean fish. Taken together, the current epidemiological evidence does not support the existence of a significant effect of total fish consumption on the risk of venous thromboembolism. © The Author(s) 2015.

Early thrombus removal strategies for acute deep venous thrombosis: clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum.

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Meissner, Mark H; Gloviczki, Peter; Comerota, Anthony J; Dalsing, Michael C; Eklof, Bo G; Gillespie, David L; Lohr, Joann M; McLafferty, Robert B; Murad, M Hassan; Padberg, Frank; Pappas, Peter; Raffetto, Joseph D; Wakefield, Thomas W

2012-05-01

The anticoagulant treatment of acute deep venous thrombosis (DVT) has been historically directed toward the prevention of recurrent venous thromboembolism. However, such treatment imperfectly protects against late manifestations of the postthrombotic syndrome. By restoring venous patency and preserving valvular function, early thrombus removal strategies can potentially decrease postthrombotic morbidity. A committee of experts in venous disease was charged by the Society for Vascular Surgery and the American Venous Forum to develop evidence-based practice guidelines for early thrombus removal strategies, including catheter-directed pharmacologic thrombolysis, pharmacomechanical thrombolysis, and surgical thrombectomy. Evidence-based recommendations are based on a systematic review and meta-analysis of the relevant literature, supplemented when necessary by less rigorous data. Recommendations are made according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, incorporating the strength of the recommendation (strong: 1; weak: 2) and an evaluation of the level of the evidence (A to C). On the basis of the best evidence currently available, we recommend against routine use of the term "proximal venous thrombosis" in favor of more precise characterization of thrombi as involving the iliofemoral or femoropopliteal venous segments (Grade 1A). We further suggest the use of early thrombus removal strategies in ambulatory patients with good functional capacity and a first episode of iliofemoral DVT of venous outflow obstruction (Grade 1A). We suggest pharmacomechanical strategies over catheter-directed pharmacologic thrombolysis alone if resources are available and that surgical thrombectomy be considered if thrombolytic therapy is contraindicated (Grade 2C). Most data regarding early thrombus removal strategies are of low quality but do suggest patient-important benefits with respect to reducing postthrombotic morbidity. We

Improving prediction of recanalization in acute large-vessel occlusive stroke.

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Vanacker, P; Lambrou, D; Eskandari, A; Maeder, P; Meuli, R; Ntaios, G; Michel, P

2014-06-01

Recanalization in acute ischemic stroke with large-vessel occlusion is a potent indicator of good clinical outcome. To identify easily available clinical and radiologic variables predicting recanalization at various occlusion sites. All consecutive, acute stroke patients from the Acute STroke Registry and Analysis of Lausanne (2003-2011) who had a large-vessel occlusion on computed tomographic angiography (CTA) (< 12 h) were included. Recanalization status was assessed at 24 h (range: 12-48 h) with CTA, magnetic resonance angiography, or ultrasonography. Complete and partial recanalization (corresponding to the modified Treatment in Cerebral Ischemia scale 2-3) were grouped together. Patients were categorized according to occlusion site and treatment modality. Among 439 patients, 51% (224) showed complete or partial recanalization. In multivariate analysis, recanalization of any occlusion site was most strongly associated with endovascular treatment, including bridging therapy (odds ratio [OR] 7.1, 95% confidence interval [CI] 2.2-23.2), and less so with intravenous thrombolysis (OR 1.6, 95% CI 1.0-2.6) and recanalization treatments performed beyond guidelines (OR 2.6, 95% CI 1.2-5.7). Clot location (large vs. intermediate) and tandem pathology (the combination of intracranial occlusion and symptomatic extracranial stenosis) were other variables discriminating between recanalizers and non-recanalizers. For patients with intracranial occlusions, the variables significantly associated with recanalization after 24 h were: baseline National Institutes of Health Stroke Scale (NIHSS) (OR 1.04, 95% CI 1.02-1.1), Alberta Stroke Program Early CT Score (ASPECTS) on initial computed tomography (OR 1.2, 95% CI 1.1-1.3), and an altered level of consciousness (OR 0.2, 95% CI 0.1-0.5). Acute endovascular treatment is the single most important factor promoting recanalization in acute ischemic stroke. The presence of extracranial vessel stenosis or occlusion decreases

Simultaneous Iliac Vein Bovine Pericardial Patch Venoplasty and Creation of PTFE Lower Limb Arteriovenous Fistula Graft for Rescue Vascular Access.

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Meecham, Lewis; Fisher, Owain; Kirby, George; Evans, Richard; Buxton, Pauline; Legge, Jocelyn; Rajagopalan, Sriram; Asquith, John; Pherwani, Arun

2016-10-01

We present a case of external iliac vein patch venoplasty to accommodate rescue vascular access via a polytetrafluoroethylene loop arteriovenous fistula graft (AVG) for a patient with multiple central venous stenoses. A 35-year-old female with anti-glomerular basement membrane antibody disease required rescue vascular access for hemodialysis. Repeated occlusion and/or thrombosis of long-term central venous access cannulae, to facilitate dialysis, had caused stenosis of brachiocephalic veins: right external iliac vein and occlusion of the left common iliac vein. A previous right brachiobasilic fistula had occluded within 1 year. No other upper limb options for arteriovenous fistula (AVF) were available. A right external iliac vein bovine patch angioplasty concurrently with a polytetrafluoroethylene AV graft between common femoral artery and common femoral vein was performed to restore venous patency and allow rescue dialysis access. At 3-year follow-up, the fistula remains widely patent with 2 L/min flow rates and no recurrent stenosis to the treated iliac vein. She has not required any further surgical or interventional radiological procedures to maintain fistula or central venous patency. Central venous stenosis or occlusion is common for patients requiring dialysis, especially those with multiple previous long-term central venous cannulations. If restriction of outflow is present, AVF may fail. Venous patch angioplasty in these cases is a successful technique, allowing AVF formation and long-term patency. Central venous stenosis can be treated successfully with patch venoplasty to accommodate AVF/AVG formation for rescue vascular access; this is a potentially lifesaving intervention for patients requiring dialysis. Copyright © 2016 Elsevier Inc. All rights reserved.

Practical aspects of treatment with target specific anticoagulants: initiation, payment and current market, transitions, and venous thromboembolism treatment.