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Sample records for large vessel occlusive

  1. Large cerebral vessel occlusive disease in Lyme neuroborreliosis.

    Science.gov (United States)

    Klingebiel, R; Benndorf, G; Schmitt, M; von Moers, A; Lehmann, R

    2002-02-01

    We report on a 12-year-old, previously healthy girl with an acute hemiparesis as the predominant clinical manifestation of Lyme neuroborreliosis (LNB). The diagnosis of LNB was based on cerebrospinal fluid (CSF) studies, laboratory findings and the clinical course whereas the patient's history and the lack of characteristic skin lesions obscured the diagnosis in the beginning. After four weeks of antibiotic and physiotherapeutic treatment, the hemiparetic symptoms had completely resolved. Although evidence of vasculitic and perivascular inflammation in LNB has been described in the literature, large cerebral vessel occlusive disease represents a rare finding. Appropriate treatment strategies can lead to good clinical rehabilitation, as shown in this case, making the timely diagnosis a crucial issue. We conclude that LNB should be considered in every stroke-like episode of unknown origin in children, even in the absence of a history of a tick bite or typical skin lesions.

  2. Value of CT angiography in anterior circulation large vessel occlusive stroke: Imaging findings, pearls, and pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Power, Sarah, E-mail: drsarahpower@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); McEvoy, Sinead H., E-mail: sineadmcevoy@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Cunningham, Jane, E-mail: janecunningham0708@gmail.com [Department of Radiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Ti, Joanna P., E-mail: joannapearlyti@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Looby, Seamus, E-mail: seamuslooby@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); O' Hare, Alan, E-mail: alanohare@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Williams, David, E-mail: davidwilliams@rcsi.ie [Department of Geriatrics and Stroke Medicine, Royal College of Surgeons in Ireland (RCSI) and Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Brennan, Paul, E-mail: paulbrennan@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Thornton, John, E-mail: johnthornton@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland)

    2015-07-15

    Highlights: • Site of occlusion determines potential collateralization routes and impacts outcome. • Multifocality of arterial occlusion is common, seen in approximately 20% of cases. • ICA false occlusion sign can be seen in setting of ICA stenosis or carotid T occlusion. • False patency sign: hyperdense thrombus/calcified occlusive plaque misinterpreted as patent vessel. • Additional abnormalities on CTA may infer stroke mechanism or alter decision making. - Abstract: Hyperacute stroke imaging is playing an increasingly important role in determining management decisions in acute stroke patients, particularly patients with large vessel occlusive stroke who may benefit from endovascular intervention. CT angiography (CTA) is an important tool in the work-up of the acute stroke patient. It reliably detects large occlusive thrombi in proximal cerebral arteries and is a quick and highly accurate method in identifying candidates for endovascular stroke treatment. In this article we review the imaging findings on CTA in acute large vessel occlusive stroke using a pictorial case based approach. We retrospectively reviewed CTA studies in 48 patients presenting with acute anterior circulation large vessel occlusive stroke who were brought for intra-arterial acute stroke intervention. We discuss and illustrate patterns of proximal intracranial arterial occlusion, collateralization to the occluded territory, as well as reviewing some important pearls, pitfalls and teaching points in CTA assessment of the acute stroke patient. Performed from the level of the aortic arch CTA also gives valuable information regarding the state of other vessels in the acute stroke patient, identifying additional significant vascular stenoses or occlusions, and as we illustrate, can demonstrate other clinically significant findings which may impact on patient management and outcome.

  3. The Amplatzer vascular plug for large vessel occlusion in the endovascular management of aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Ratnam, Lakshmi A.; Walkden, Richard M.; Munneke, Graham J.; Morgan, Robert A.; Belli, Anna-Maria [St.George' s Hospital, Department of Radiology, London (United Kingdom)

    2008-09-15

    The Amplatzer vascular plug (AVP) is derived from the Amplatzer device used in correction of cardiac septal defects. We present a large series of the use of the AVP in the endovascular management of aneurysms. Three patients with a combination of aortic and peripheral aneurysms underwent embolisation with the AVP. Plugs with 10-16 mm diameter were used and delivered using introducer/guiding sheaths. A total of 16 internal iliac arteries, 2 common iliac arteries (CIA), 4 subclavian (SCA) arteries, 1 superior mesenteric (SMA) and 1 popliteal artery were embolised. Successful occlusion with the AVP was achieved in 21 out of 24 vessels (87.5%), of which 18 (75%) occluded immediately and 3 (12.5%) were delayed occlusions. The three patients who are considered to have failed to occlude with the AVP required the use of additional embolic agents. At the end of the 17-month follow-up all 24 target vessels had occluded. Two patients developed persistent buttock claudication, and one had a left hemiparesis. The AVP is useful as an adjunctive device in the management of aneurysms. It has a particular role in embolisation of large-diameter vessels with a short implantation zone. The device is safe and easy to use. (orig.)

  4. Significance of large vessel intracranial occlusion causing acute ischemic stroke and TIA.

    Science.gov (United States)

    Smith, Wade S; Lev, Michael H; English, Joey D; Camargo, Erica C; Chou, Maggie; Johnston, S Claiborne; Gonzalez, Gilberto; Schaefer, Pamela W; Dillon, William P; Koroshetz, Walter J; Furie, Karen L

    2009-12-01

    Acute ischemic stroke due to large vessel occlusion (LVO)-vertebral, basilar, carotid terminus, middle and anterior cerebral arteries-likely portends a worse prognosis than stroke unassociated with LVO. Because little prospective angiographic data have been reported on a cohort of unselected patients with stroke and with transient ischemic attack, the clinical impact of LVO has been difficult to quantify. The Screening Technology and Outcome Project in Stroke Study is a prospective imaging-based study of stroke outcomes performed at 2 academic medical centers. Patients with suspected acute stroke who presented within 24 hours of symptom onset and who underwent multimodality CT/CT angiography were approached for consent for collection of clinical data and 6-month assessment of outcome. Demographic and clinical variables and 6-month modified Rankin Scale scores were collected and combined with blinded interpretation of the CT angiography data. The OR of each variable, including occlusion of intracranial vascular segment in predicting good outcome and 6-month mortality, was calculated using univariate and multivariate logistic regression. Over a 33-month period, 735 patients with suspected stroke were enrolled. Of these, 578 were adjudicated as stroke and 97 as transient ischemic attack. Among patients with stroke, 267 (46%) had LVO accounting for the stroke and 13 (13%) of patients with transient ischemic attack had LVO accounting for transient ischemic attack symptoms. LVO predicted 6-month mortality (OR, 4.5; 95% CI, 2.7 to 7.3; PStroke Scale and age, independently predicted outcome. Large vessel intracranial occlusion accounted for nearly half of acute ischemic strokes in unselected patients presenting to academic medical centers. In addition to age and baseline stroke severity, occlusion of either the basilar or internal carotid terminus segment is an independent predictor of outcome at 6 months.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  6. Large Vessel Occlusion Scales Increase Delivery to Endovascular Centers Without Excessive Harm From Misclassifications.

    Science.gov (United States)

    Zhao, Henry; Coote, Skye; Pesavento, Lauren; Churilov, Leonid; Dewey, Helen M; Davis, Stephen M; Campbell, Bruce C V

    2017-03-01

    Clinical large vessel occlusion (LVO) triage scales were developed to identify and bypass LVO to endovascular centers. However, there are concerns that scale misclassification of patients may cause excessive harm. We studied the settings where misclassifications were likely to occur and the consequences of these misclassifications in a representative stroke population. Prospective data were collected from consecutive ambulance-initiated stroke alerts at 2 stroke centers, with patients stratified into typical (LVO with predefined severe syndrome and non-LVO without) or atypical presentations (opposite situations). Five scales (Rapid Arterial Occlusion Evaluation [RACE], Los Angeles Motor Scale [LAMS], Field Assessment Stroke Triage for Emergency Destination [FAST-ED], Prehospital Acute Stroke Severity scale [PASS], and Cincinnati Prehospital Stroke Severity Scale [CPSSS]) were derived from the baseline National Institutes of Health Stroke Scale scored by doctors and analyzed for diagnostic performance compared with imaging. Of a total of 565 patients, atypical presentations occurred in 31 LVO (38% of LVO) and 50 non-LVO cases (10%). Most scales correctly identified >95% of typical presentations but internal carotid artery occlusions, with National Institutes of Health Stroke Scale score ≥6 (5% of LVO) being missed and 9 non-LVO infarcts (5%) bypassing the nearest thrombolysis center. Atypical presentations accounted for the bulk of scale misclassifications, but the majority of these misclassifications were not detrimental, and use of LVO scales would significantly increase timely delivery to endovascular centers, with only a small proportion of non-LVO infarcts bypassing the nearest thrombolysis center. Our findings, however, would require paramedics to score as accurately as doctors, and this translation is made difficult by weaknesses in current scales that need to be addressed before widespread adoption. © 2017 American Heart Association, Inc.

  7. Blood Pressure and Penumbral Sustenance in Stroke from Large Vessel Occlusion

    Science.gov (United States)

    Regenhardt, Robert W.; Das, Alvin S.; Stapleton, Christopher J.; Chandra, Ronil V.; Rabinov, James D.; Patel, Aman B.; Hirsch, Joshua A.; Leslie-Mazwi, Thabele M.

    2017-01-01

    The global burden of stroke remains high, and of the various subtypes of stroke, large vessel occlusions (LVOs) account for the largest proportion of stroke-related death and disability. Several randomized controlled trials in 2015 changed the landscape of stroke care worldwide, with endovascular thrombectomy (ET) now the standard of care for all eligible patients. With the proven success of this therapy, there is a renewed focus on penumbral sustenance. In this review, we describe the ischemic penumbra, collateral circulation, autoregulation, and imaging assessment of the penumbra. Blood pressure goals in acute stroke remain controversial, and we review the current data and suggest an approach for induced hypertension in the acute treatment of patients with LVOs. Finally, in addition to reperfusion and enhanced perfusion, efforts focused on developing therapeutic targets that afford neuroprotection and augment neural repair will gain increasing importance. ET has revolutionized stroke care, and future emphasis will be placed on promoting penumbral sustenance, which will increase patient eligibility for this highly effective therapy and reduce overall stroke-related death and disability. PMID:28717354

  8. New Cerebral Microbleeds After Mechanical Thrombectomy for Large-Vessel Occlusion Strokes

    Science.gov (United States)

    Shi, Zhong-Song; Duckwiler, Gary R.; Jahan, Reza; Tateshima, Satoshi; Gonzalez, Nestor R.; Szeder, Viktor; Saver, Jeffrey L.; Kim, Doojin; Ali, Latisha K.; Starkman, Sidney; Vespa, Paul M.; Salamon, Noriko; Villablanca, J. Pablo; Viñuela, Fernando; Feng, Lei; Loh, Yince; Liebeskind, David S.

    2015-01-01

    Abstract The interval appearance of cerebral microbleeds (CMBs) after endovascular treatment has never been described. We investigated the frequency and predictors of new CMBs that developed shortly after mechanical thrombectomy for acute ischemic stroke, and its impact on clinical outcome. We retrospectively analyzed patients with large-vessel occlusion strokes treated with Merci Retriever, Penumbra System, or stent-retriever devices. Serial T2∗-weighted gradient-recall echo (GRE) magnetic resonance imaging (MRI) before and 48 h after endovascular thrombectomy were assessed to identify new CMBs. We examined independent factors associated with new CMBs after mechanical thrombectomy. We analyzed the association of the presence, burden, and distribution of new CMBs with clinical outcome. A total of 187 consecutive patients with serial GRE were enrolled in this study. CMBs were evident in 36 (19.3%) patients before mechanical thrombectomy. New CMBs occurred in 41 (21.9%) patients after mechanical thrombectomy. Of the 68 new CMBs, 45 appeared in the lobar location, 18 in the deep location and 5 in the infratentorial location. The presence of baseline CMBs was associated with new CMBs after mechanical thrombectomy (OR 5.38; 95% CI 2.13–13.59; P rates of hemorrhagic transformation, in-hospital mortality, and modified Rankin Scale score 4 to 6 at discharge. New CMBs are common after mechanical thrombectomy in one-fifth of patients with acute ischemic stroke. Baseline CMBs before mechanical thrombectomy predicts the development of new CMBs. New CMBs after mechanical thrombectomy do not influence clinical outcome. PMID:26632753

  9. New Cerebral Microbleeds After Mechanical Thrombectomy for Large-Vessel Occlusion Strokes.

    Science.gov (United States)

    Shi, Zhong-Song; Duckwiler, Gary R; Jahan, Reza; Tateshima, Satoshi; Gonzalez, Nestor R; Szeder, Viktor; Saver, Jeffrey L; Kim, Doojin; Ali, Latisha K; Starkman, Sidney; Vespa, Paul M; Salamon, Noriko; Villablanca, J Pablo; Viñuela, Fernando; Feng, Lei; Loh, Yince; Liebeskind, David S

    2015-11-01

    The interval appearance of cerebral microbleeds (CMBs) after endovascular treatment has never been described. We investigated the frequency and predictors of new CMBs that developed shortly after mechanical thrombectomy for acute ischemic stroke, and its impact on clinical outcome.We retrospectively analyzed patients with large-vessel occlusion strokes treated with Merci Retriever, Penumbra System, or stent-retriever devices. Serial T2*-weighted gradient-recall echo (GRE) magnetic resonance imaging (MRI) before and 48 h after endovascular thrombectomy were assessed to identify new CMBs. We examined independent factors associated with new CMBs after mechanical thrombectomy. We analyzed the association of the presence, burden, and distribution of new CMBs with clinical outcome.A total of 187 consecutive patients with serial GRE were enrolled in this study. CMBs were evident in 36 (19.3%) patients before mechanical thrombectomy. New CMBs occurred in 41 (21.9%) patients after mechanical thrombectomy. Of the 68 new CMBs, 45 appeared in the lobar location, 18 in the deep location and 5 in the infratentorial location. The presence of baseline CMBs was associated with new CMBs after mechanical thrombectomy (OR 5.38; 95% CI 2.13-13.59; P CMBs did not have increased rates of hemorrhagic transformation, in-hospital mortality, and modified Rankin Scale score 4 to 6 at discharge.New CMBs are common after mechanical thrombectomy in one-fifth of patients with acute ischemic stroke. Baseline CMBs before mechanical thrombectomy predicts the development of new CMBs. New CMBs after mechanical thrombectomy do not influence clinical outcome.

  10. Penumbra Stroke System as an "add-on" for the treatment of large vessel occlusive disease following thrombolysis: first results.

    Science.gov (United States)

    Struffert, Tobias; Köhrmann, Martin; Engelhorn, Tobias; Nowe, Tim; Richter, Gregor; Schellinger, Peter D; Schwab, Stefan; Doerfler, Arnd

    2009-09-01

    The Penumbra Stroke System (PSS) was cleared for use in patients with ischemic stroke by the FDA in January 2008. We describe our experience of using this new system in acute large vessel occlusive disease following thrombolysis. Fifteen consecutive patients (mean age 60 years) suffering from acute ischemic stroke were treated with the PSS after intravenous or intra-arterial standard treatment with tissue plasminogen activator (n = 14) or ReoPro (n = 1). All patients presented with TIMI 3 before use of the PSS. Carotid stenting (n = 3) and intracranial balloon angioplasty or stenting (n = 2) were performed if indicated. Neurological evaluation was performed using the NIHSS score and the mRS score. Initial median NIHSS score in 12 patients with occlusions in the anterior circulation was 15; three patients with basilar artery occlusion presented with coma. Median symptom to procedure start time was 151 min. In the anterior circulation, 9 of the 12 target vessels were recanalised successfully (TIMI 2 and 3). The rate of patients with independent clinical outcome (mRS occlusions could be recanalised in all cases to TIMI 3. The clinical result after 90 days was mRS 4 in two cases and mRS 5 in one case. Symptomatic haemorrhage did not occur. The PSS can safely be used for recanalisation in patients with acute ischemic stroke due to large vessel occlusion, who have already received thrombolysis treatment. The recanalisation rate was 80%. Symptomatic haemorrhage did not occur. Randomized trials may demonstrate that endovascular mechanical thrombectomy improves patient outcome.

  11. A population-based incidence of M2 strokes indicates potential expansion of large vessel occlusions amenable to endovascular therapy.

    Science.gov (United States)

    Rai, Ansaar T; Domico, Jennifer R; Buseman, Chelsea; Tarabishy, Abdul R; Fulks, Daniel; Lucke-Wold, Noelle; Boo, SoHyun; Carpenter, Jeffrey S

    2017-09-28

    M2 occlusions may result in poor outcomes and potentially benefit from endovascular therapy. Data on the rate of M2 strokes is lacking. Patients with acute ischemic stroke discharged over a period of 3 years from a tertiary level hospital in the 'stroke belt' were evaluated for M2 occlusions on baseline vascular imaging. Regional and national incidence was calculated from discharge and multicounty data. There were 2739 ICD-9 based AIS discharges. M2 occlusions in 116 (4%, 95% CI 3.5% to 5%) patients constituted the second most common occlusion site. The median National Institute of Health Stroke Scale (NIHSS) score was 12 (IQR 5-18). Good outcomes were observed in 43% (95% CI 34% to 53%), poor outcomes in 57% (95% CI 47% to 66%), and death occurred in 27% (95% CI 19% to 37%) of patients. Receiver operating characteristics curves showed the NIHSS to be predictive of outcomes (area under the curve 0.829, 95% CI 0.745 to 0.913, p<0.0001). An NIHSS score ≥9 was the optimal cut-off point for predicting poor outcomes (sensitivity 85.7%, specificity 67.4%). 71 (61%) patients had an NIHSS score ≥9 and 45 (39%) an NIHSS score <9. The rate of good-outcome was 22.6% for NIHSS score ≥9 versus 78.4% for NIHSSscore <9 (OR=0.08, 95% CI 0.03 to 0.21, p<0.0001). Mortality was 42% for NIHSS score ≥9versus 2.7% for NIHSS score <9 (OR=26, 95% CI 3.3 to 202, p<0.0001). Infarct volume was 57 (±55.7) cm(3) for NIHSS score ≥9 versus 30 (±34)cm(3) for NIHSS score <9 (p=0.003). IV recombinant tissue plasminogen activator (rtPA) administered in 28 (24%) patients did not affect outcomes. The rate of M2 occlusions was 7 (95% CI 5 to 9)/100 000 people/year (3%, 95% CI 2% to 4%), giving an incidence of 21 176 (95% CI 15 282 to 29 247)/year. Combined with M1, internal carotid artery terminus and basilar artery, this yields a 'large vessel occlusion (LVO)+M2' rate of 31 (95% CI 26 to 35)/100 000 people/year and a national incidence of 99 227 (95% CI 84 004 to 112

  12. Large intracranial vessel occlusion arising after radiotherapy for craniopharingioma. A case report and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Osamu; Iwasa, Satoshi; Kohno, Norio; Nozaki, Miwako (Kiryu Kohsei General Hospital, Gunma (Japan))

    1994-10-01

    We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography showed complete occlusion of the terminal portion of the internal carotid artery and collateral vessels from the middle meningeal artery to the middle cerebral artery through the shunt burr hole. He has been treated conservatively and is doing well except for slight right hemiparesis. Our experience shows that the risk of occlusive cerebrovasculopathy after radiation therapy should be taken into account, especially in children. (author).

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

    Energy Technology Data Exchange (ETDEWEB)

    Froelich, Andreas M.J.; Wolff, Sarah Lena; Psychogios, Marios N.; Schramm, Ramona; Knauth, Michael; Schramm, Peter [University Medical Centre Goettingen, Department of Neuroradiology, Goettingen (Germany); Klotz, Ernst [Computed Tomography H IM CR R and D PA, Siemens AG, Forchheim (Germany); Wasser, Katrin [University Medical Centre Goettingen, Department of Neurology, Goettingen (Germany)

    2014-02-15

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

  14. Penumbra Stroke System as an ''add-on'' for the treatment of large vessel occlusive disease following thrombolysis: first results

    Energy Technology Data Exchange (ETDEWEB)

    Struffert, Tobias; Engelhorn, Tobias; Richter, Gregor; Doerfler, Arnd [University of Erlangen-Nuremberg, Department of Neuroradiology, Erlangen (Germany); Koehrmann, Martin; Nowe, Tim; Schellinger, Peter D.; Schwab, Stefan [University of Erlangen-Nuremberg, Department of Neurology, Erlangen (Germany)

    2009-09-15

    The Penumbra Stroke System (PSS) was cleared for use in patients with ischemic stroke by the FDA in January 2008. We describe our experience of using this new system in acute large vessel occlusive disease following thrombolysis. Fifteen consecutive patients (mean age 60 years) suffering from acute ischemic stroke were treated with the PSS after intravenous or intra-arterial standard treatment with tissue plasminogen activator (n = 14) or ReoPro (n = 1). All patients presented with TIMI 3 before use of the PSS. Carotid stenting (n = 3) and intracranial balloon angioplasty or stenting (n = 2) were performed if indicated. Neurological evaluation was performed using the NIHSS score and the mRS score. Initial median NIHSS score in 12 patients with occlusions in the anterior circulation was 15; three patients with basilar artery occlusion presented with coma. Median symptom to procedure start time was 151 min. In the anterior circulation, 9 of the 12 target vessels were recanalised successfully (TIMI 2 and 3). The rate of patients with independent clinical outcome (mRS {<=} 2) was 42%. One patient died 5 days after unsuccessful treatment, one after 28 days and one after 85 days owing to heart attack. Basilar artery occlusions could be recanalised in all cases to TIMI 3. The clinical result after 90 days was mRS 4 in two cases and mRS 5 in one case. Symptomatic haemorrhage did not occur. The PSS can safely be used for recanalisation in patients with acute ischemic stroke due to large vessel occlusion, who have already received thrombolysis treatment. The recanalisation rate was 80%. Symptomatic haemorrhage did not occur. Randomized trials may demonstrate that endovascular mechanical thrombectomy improves patient outcome. (orig.)

  15. Photoacoustic removal of occlusions from blood vessels

    Science.gov (United States)

    Visuri, Steven R.; Da Silva, Luiz B.; Celliers, Peter M.; London, Richard A.; Maitland, IV, Duncan J.; Esch, Victor C.

    2002-01-01

    Partial or total occlusions of fluid passages within the human body are removed by positioning an array of optical fibers in the passage and directing treatment radiation pulses along the fibers, one at a time, to generate a shock wave and hydrodynamics flows that strike and emulsify the occlusions. A preferred application is the removal of blood clots (thrombin and embolic) from small cerebral vessels to reverse the effects of an ischemic stroke. The operating parameters and techniques are chosen to minimize the amount of heating of the fragile cerebral vessel walls occurring during this photo acoustic treatment. One such technique is the optical monitoring of the existence of hydrodynamics flow generating vapor bubbles when they are expected to occur and stopping the heat generating pulses propagated along an optical fiber that is not generating such bubbles.

  16. Emergent intracranial balloon angioplasty and bailout self-expandable stent placement in acute large vessel occlusion of the anterior circulation: Experience of a single institution

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Young Jin; Seo, Jung Hwa; Jeong, Hae Woong [Busan Paik Hospital, Inje University, Busan (Korea, Republic of)

    2017-06-15

    To evaluate the outcomes of angioplasty for recanalization after acute ischemic stroke (AIS). The study population was selected from 134 patients who underwent endovascular revascularization therapy (ERT) for AIS between October 2011 and May 2014. Of those 134 patients, 39 who underwent balloon angioplasty with or without stent insertion were included in this study. Balloon angioplasty was the primary treatment for nine patients and a rescue method for 30 patients. The revascularization rate at 7 days, procedure-related complications, and clinical outcomes at 3 months were analyzed. The occlusion sites were the middle cerebral artery (n = 26), intracranial internal carotid artery (n = 10), and middle cerebral artery branch (n = 3). Angioplasty achieved successful revascularization (Thrombolysis in Cerebral Ischemia grade 2b–3) in 76.9% of patients. Computed tomography angiography performed 7 days post-procedure revealed a maintained reperfusion in 82.8% of successful cases. Only two patients had symptomatic intracerebral hemorrhage. At the 3-month follow-up, 18 (48.6%) and 10 (27.0%) patients showed good and poor functional outcomes, respectively (modified Rankin Scale scores, 0–2 and 5–6). Emergent balloon angioplasty and bailout self-expandable stent placement may be safe and effective for achieving successful revascularization in acute large vessel occlusion of the anterior circulation. It could be a feasible rescue method as well as a primary method for ERT.

  17. 21 CFR 870.2890 - Vessel occlusion transducer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vessel occlusion transducer. 870.2890 Section 870... transducer. (a) Identification. A vessel occlusion transducer is a device used to provide an electrical..., sound, and ultrasonic transducers. (b) Classification. Class II (performance standards). ...

  18. Amplatzer vascular plug for rapid vessel occlusion in interventional neuroradiology.

    Science.gov (United States)

    Banfield, Jillian C; Shankar, Jai Jai Shiva

    2016-02-01

    The purpose of this paper is to report different uses of endovascular Amplatzer vascular plug (AVP) treatment for rapid vessel occlusion in the field of interventional neuroradiology. We retrospectively reviewed our interventional neuroradiology database from November 2010 to July 2015 and found nine patients who were treated with endovascular AVP. AVP was used for rapid vessel occlusion of common carotid artery (1 patient), internal carotid artery (5 patients), vertebral artery (2 patients), and internal jugular vein (1 patient). A median of three AVPs were used with almost immediate occlusion and no thromboembolic complications. Use of AVP is feasible, safe, rapid, and potentially cost-effective method for rapid occlusion of larger size vessels in the head and neck region for different indications.

  19. Intracranial Large Artery Occlusive Disease

    Institute of Scientific and Technical Information of China (English)

    Wong KS; Li H; Kay R

    2000-01-01

    @@Intracranial large artery stenosis is the most commonly found vascular lesion in stroke patient of Chinese, Hispanic and African ancestry. There .have been few studies on the epidemiology, pathophysiology, treatment and prognosis of this important disease. Recent advances in technology provide safe and reliable investigation for studying large number of patients. Transcranial Doppler is an easily accessible, cheap and reliable method to diagnose intracranial stenosis. It is suitable for screening for and monitoring the progress of intracranial stenosis. Magnetic resonance angiography and CT angiography provide the morphology of lumenal stenosis but are less accessible.

  20. Rescue Thrombectomy in Large Vessel Occlusion Strokes Leads to Better Outcomes than Intravenous Thrombolysis Alone: A ‘Real World’ Applicability of the Recent Trials

    Science.gov (United States)

    Nogueira, Raul G.; Zaidat, Osama O.; Castonguay, Alicia C.; Haussen, Diogo C.; Martin, Coleman O.; Holloway, William E.; Mueller-Kronast, Nils; English, Joey; Linfante, Italo; Dabus, Guilherme; Malisch, Tim W.; Marden, Franklin A.; Bozorgchami, Hormozd; Xavier, Andrew; Rai, Ansaar T.; Froehler, Michael T.; Badruddin, Aamir; Nguyen, Thanh N.; Taqi, M. Asif; Abraham, Michael G.; Janardhan, Vallabh; Yoo, Albert J.; Shaltoni, Hashem; Abou-Chebl, Alex; Chen, Peng R.; Britz, Gavin W.; Novakovic, Roberta; Nanda, Ashish; Kaushal, Ritesh; Issa, Mohammad A.; Frankel, Michael R.; Gupta, Rishi

    2016-01-01

    Background The Interventional Management of Stroke III (IMS-III) trial demonstrated no benefit for intravenous recombinant tissue plasminogen activator (IV rt-PA) followed by endovascular therapy versus IV rt-PA alone. However, IMS-III mostly included earlier generation devices. The recent thrombectomy trials have incorporated the stent-retriever technology, but their generalizability remains unknown. Methods The North American Solitaire Acute Stroke (NASA) registry recruited patients treated with the Solitaire FR™ device between March 2012 and February 2013. The NASA-IMS-III-Like Group (NILG baseline NIHSS score ≥10 who received IV rt-PA) was compared to the IV rt-PA and IV + intra-arterial (IA)-IMS-III groups and the MR CLEAN, ESCAPE, SWIFT Prime, and REVASCAT trial controls to assess the stent-retriever treatment in the ‘real-world’ setting. The NILG was also compared to non-IV rt-PA NASA patients to evaluate the impact of IV rt-PA on thrombectomy. Results A total of 136 of the 354 NASA patients fulfilled criteria for the NILG. Baseline characteristics were well balanced across groups. Time from onset to puncture was higher in NILG than IV+IA-IMS-III patients (274 ± 112 vs. 208 ± 47 min, p < 0.0001). Occlusions involving the intracranial ICA, MCA-M1, or basilar arteries were more common in NILG than IV+IA-IMS-III patients (91.2 vs. 47.2%, p < 0.00001). Modified thrombolysis in cerebral infarction ≥2b reperfusion was higher in NILG than IV+IA-IMS-III patients (74.3 vs. 39.6%, p < 0.00001). A 90-day modified Rankin Scale score ≤2 was more frequent in the NILG than IV+IA-IMS-III patients (51.9 vs. 40.8%, p = 0.03) and MR CLEAN (51.9 vs. 19.1%, p < 0.00001), ESCAPE (51.9 vs. 29.3%, p = 0.0002), SWIFT Prime (51.9 vs. 35.5%, p = 0.02), and REVASCAT (51.9 vs. 28.2%, p = 0.0003) controls. Symptomatic intracranial hemorrhage definitions varied across the different studies with rates ranging from 2.7% (ESCAPE) to 11.9% (NILG). The NILG 90-day mortality (24

  1. The Limit of Large Vessels

    Institute of Scientific and Technical Information of China (English)

    Yang Peiju

    2011-01-01

    On Feb 21(st),the industry was shocked by the news that AP Moller-Maersk placed an order of 10 container ships of 18,000 TEU with the South Korean ship yards.The order brings the development of large vessels to a new climax and at the same time puts forward a series of research subjects to the industry,such as what is the limit for the development of large vessels,whether ship safety can be guaranteed,and etc.

  2. [Balloon occlusion test of the internal carotid artery for evaluating resectability of blood vessel infiltrating cervical metastasis of advanced head and neck cancers--Heidelberg experience].

    Science.gov (United States)

    Dietz, A; von Kummer, R; Adams, H P; Kneip, M; Galito, P; Maier, H

    1993-11-01

    During the last two years 17 patients of the ENT-Department of the University of Heidelberg suffering from squamous-cell carcinomas of the head and neck underwent a balloon occlusion test of the internal carotid artery (ICA). The investigation was performed because of tumorous infiltration of the large cervical vessels. The balloon occlusion of the ICA was accomplished at the Department of Neuroradiology of the University of Heidelberg. While stopping bloodflow in the ICA of one side for 15-20 min, clinical, electrophysiological and Doppler sonographic monitoring was performed, to detect severe cerebral complications. The specific electrophysiological monitoring contained the detection of MSSEP's (median nerve stimulated somatosensorial evoked potentials) and TCMEP's (transcortical motor evoked potentials) during test occlusion. Balloon occlusion was not possible in three patients because of severe arteriosclerosis. Test occlusion had to be discontinued in three patients because of clinical complications (temporary amaurosis, orthostatic complications). Finally, seven patients showed contraindications during test occlusion for permanent occlusion of the ICA. Four patients had a permanent occlusion of the ICA after tumour resection. In two patients the ICA was removed without problems in test occlusion. The third patient underwent a permanent carotid occlusion because of bleeding complications (in spite of poor clinical tolerance of the test occlusion). In the fourth patient, only intraoperative neuromonitoring with MSSEP's was conducted before permanent carotid occlusion. All four patients did not show any neurological deficits after resection of the ICA. Neurophysiological monitoring played an important role in predicting cerebral complications after permanent occlusion of the ICA.

  3. An adaptive occlusion culling algorithm for use in large ves

    DEFF Research Database (Denmark)

    Bormann, Karsten

    2000-01-01

    The Hierarchical Occlusion Map algorithm is combined with Frustum Slicing to give a simpler occlusion-culling algorithm that more adequately caters to large, open VEs. The algorithm adapts to the level of visual congestion and is well suited for use with large, complex models with long mean free...

  4. Mechanical Recanalization of Subacute Vessel Occlusion in Peripheral Arterial Disease with a Directional Atherectomy Catheter

    Energy Technology Data Exchange (ETDEWEB)

    Massmann, Alexander, E-mail: Alexander.Massmann@uks.eu; Katoh, Marcus [Saarland University Hospital, Department of Diagnostic and Interventional Radiology (Germany); Shayesteh-Kheslat, Roushanak [Saarland University Hospital, Department of General Surgery, Visceral, Vascular, and Pediatric Surgery (Germany); Buecker, Arno [Saarland University Hospital, Department of Diagnostic and Interventional Radiology (Germany)

    2012-10-15

    Purpose: To retrospectively examine the technical feasibility and safety of directional atherectomy for treatment of subacute infrainguinal arterial vessel occlusions. Methods: Five patients (one woman, four men, age range 51-81 years) with peripheral arterial disease who experienced sudden worsening of their peripheral arterial disease-related symptoms during the last 2-6 weeks underwent digital subtraction angiography, which revealed vessel occlusion in native popliteal artery (n = 4) and in-stent occlusion of the superficial femoral artery (n = 1). Subsequently, all patients were treated by atherectomy with the SilverHawk (ev3 Endovascular, USA) device. Results: The mean diameter of treated vessels was 5.1 {+-} 1.0 mm. The length of the occlusion ranged 2-14 cm. The primary technical success rate was 100%. One patient experienced a reocclusion during hospitalization due to heparin-induced thrombocytopenia. There were no further periprocedural complications, in particular no peripheral embolizations, until hospital discharge or during the follow-up period of 1 year. Conclusion: The recanalization of infrainguinal arterial vessel occlusions by atherectomy with the SilverHawk device is technically feasible and safe. In our limited retrospective study, it was associated with a high technical success rate and a low procedure-related complication rate.

  5. Threshold for NIH stroke scale in predicting vessel occlusion and functional outcome after stroke thrombolysis.

    Science.gov (United States)

    Cooray, Charith; Fekete, Klara; Mikulik, Robert; Lees, Kennedy R; Wahlgren, Nils; Ahmed, Niaz

    2015-08-01

    Data are limited on optimal threshold for baseline National Institutes of Health Stroke Scale in predicting outcome after stroke thrombolysis (intravenous thrombolysis). Finding thresholds for baseline National Institutes of Health Stroke Scale scores that predict functional outcome and baseline vessel occlusion. We analyzed 44 331 patients with available modified Rankin Scale score at three-months and 11 632 patients with computed tomography/magnetic resonance angiography documented vessel occlusion at baseline in the SITS-International Stroke Thrombolysis Register. Main outcomes were functional independency (modified Rankin Scale 0-2) at three-months and baseline vessel occlusion. We obtained area under the curves by receiver operating characteristic analysis and calculated multivariately adjusted odds ratio for the outcomes of interest based on baseline National Institutes of Health Stroke Scale scores. For functional independency, National Institutes of Health Stroke Scale scores of 12 (area under the curve 0·775) and for baseline vessel occlusion, scores of 11 (area under the curve 0·678) were optimal threshold values. For functional independency, adjusted odds ratio decreased to 0·07 (95% CI 0·05-0·11), and for presence of baseline occlusion, aOR increased to 3·28 (95% CI 3·04-3·58) for National Institutes of Health Stroke Scale scores 12 and 11, respectively, compared with National Institutes of Health Stroke Scale score 0. National Institutes of Health Stroke Scale thresholds decreased with time from stroke onset to imaging, with 2-3 points, respectively, if time to imaging exceeded three-hours. Ideally, all acute stroke patients should have immediate access to multimodal imaging. In reality these services are limited. Baseline National Institutes of Health Stroke Scale scores of 11 and 12 were identified as markers of baseline vessel occlusion and functional independency after intravenous thrombolysis, respectively. These values are time

  6. Chorea and Retinal Vessel Occlusion in A Patient with Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Vahid Reza Ostovan

    2013-04-01

    Full Text Available Various neurological complications occur in primary or secondary antiphospholipid syndrome (APS consisting of cerebrovascular attacks, ocular events, dementia, seizure, chorea, and transverse myelopathy that are all related to the titer of antiphospholipid antibodies (aPL. We report a patient with chorea and retinal vessel occlusion as manifestations of systemic lupus erythematosus (SLE and APS. A 27-year-old man presented with progressive visual field defect and decreases visual acuity of right eye (OD as well as involuntary movements in both hands and slurred speech. Investigations led to the diagnosis of SLE and APS. Anticoagulant and immunosuppressant was started for him. As his condition improved, the prednisolone was gradually tapered. This is the first case report of concomitant retinal vessel occlusion and chorea in SLE and APS.

  7. Subadventitial techniques for chronic total occlusion percutaneous coronary intervention: The concept of "vessel architecture".

    Science.gov (United States)

    Azzalini, Lorenzo; Carlino, Mauro; Brilakis, Emmanouil S; Vo, Minh; Rinfret, Stéphane; Uretsky, Barry F; Karmpaliotis, Dimitri; Colombo, Antonio

    2017-03-17

    Despite improvements in guidewire technologies, the traditional antegrade wire escalation approach to chronic total occlusion (CTO) recanalization is successful in only 60-80% of selected cases. In particular, long, calcified, and tortuous occlusions are less successfully approached with a true-to-true lumen approach. Frequently, the guidewire tracks into the subadventitial space, with no guarantee of distal re-entry into the true lumen. The ability to manage the subadventitial space has been a key step in the tremendous improvement in success rates of contemporary CTO percutaneous coronary intervention (PCI), whether operating antegradely or retrogradely. A modern approach to CTO PCI involves understanding the concept of "vessel architecture," which is based on the distinction between coronary structures (occlusive plaque, comprising the disrupted intima and media, and the outer adventitia) and extravascular space. The vessel architecture represents a safe work environment for guidewire and device manipulation. This review provides an anatomy-based description of the concept of vessel architecture, along with a historical perspective of subadventitial techniques for CTO PCI, and outcome data of CTO PCI utilizing the subadventitial space. © 2017 Wiley Periodicals, Inc.

  8. Design and validation of a prehospital stroke scale to predict large arterial occlusion: the rapid arterial occlusion evaluation scale.

    Science.gov (United States)

    Pérez de la Ossa, Natalia; Carrera, David; Gorchs, Montse; Querol, Marisol; Millán, Mònica; Gomis, Meritxell; Dorado, Laura; López-Cancio, Elena; Hernández-Pérez, María; Chicharro, Vicente; Escalada, Xavier; Jiménez, Xavier; Dávalos, Antoni

    2014-01-01

    We aimed to develop and validate a simple prehospital stroke scale to predict the presence of large vessel occlusion (LVO) in patients with acute stroke. The Rapid Arterial oCclusion Evaluation (RACE) scale was designed based on the National Institutes of Health Stroke Scale (NIHSS) items with a higher predictive value of LVO on a retrospective cohort of 654 patients with acute ischemic stroke: facial palsy (scored 0-2), arm motor function (0-2), leg motor function (0-2), gaze (0-1), and aphasia or agnosia (0-2). Thereafter, the RACE scale was validated prospectively in the field by trained medical emergency technicians in 357 consecutive patients transferred by Emergency Medical Services to our Comprehensive Stroke Center. Neurologists evaluated stroke severity at admission and LVO was diagnosed by transcranial duplex, computed tomography, or MR angiography. Receiver operating curve, sensitivity, specificity, and global accuracy of the RACE scale were analyzed to evaluate its predictive value for LVO. In the prospective cohort, the RACE scale showed a strong correlation with NIHSS (r=0.76; P<0.001). LVO was detected in 76 of 357 patients (21%). Receiver operating curves showed a similar capacity to predict LVO of the RACE scale compared with the NIHSS (area under the curve 0.82 and 0.85, respectively). A RACE scale≥5 had sensitivity 0.85, specificity 0.68, positive predictive value 0.42, and negative predictive value 0.94 for detecting LVO. The RACE scale is a simple tool that can accurately assess stroke severity and identify patients with acute stroke with large artery occlusion at prehospital setting by medical emergency technicians.

  9. In vivo imaging of stepwise vessel occlusion in cerebral photothrombosis of mice by 19F MRI.

    Directory of Open Access Journals (Sweden)

    Gesa Weise

    Full Text Available BACKGROUND: (19F magnetic resonance imaging (MRI was recently introduced as a promising technique for in vivo cell tracking. In the present study we compared (19F MRI with iron-enhanced MRI in mice with photothrombosis (PT at 7 Tesla. PT represents a model of focal cerebral ischemia exhibiting acute vessel occlusion and delayed neuroinflammation. METHODS/PRINCIPAL FINDINGS: Perfluorocarbons (PFC or superparamagnetic iron oxide particles (SPIO were injected intravenously at different time points after photothrombotic infarction. While administration of PFC directly after PT induction led to a strong (19F signal throughout the entire lesion, two hours delayed application resulted in a rim-like (19F signal at the outer edge of the lesion. These findings closely resembled the distribution of signal loss on T2-weighted MRI seen after SPIO injection reflecting intravascular accumulation of iron particles trapped in vessel thrombi as confirmed histologically. By sequential administration of two chemically shifted PFC compounds 0 and 2 hours after illumination the different spatial distribution of the (19F markers (infarct core/rim could be visualized in the same animal. When PFC were applied at day 6 the fluorine marker was only detected after long acquisition times ex vivo. SPIO-enhanced MRI showed slight signal loss in vivo which was much more prominent ex vivo indicative for neuroinflammation at this late lesion stage. CONCLUSION: Our study shows that vessel occlusion can be followed in vivo by (19F and SPIO-enhanced high-field MRI while in vivo imaging of neuroinflammation remains challenging. The timing of contrast agent application was the major determinant of the underlying processes depicted by both imaging techniques. Importantly, sequential application of different PFC compounds allowed depiction of ongoing vessel occlusion from the core to the margin of the ischemic lesions in a single MRI measurement.

  10. Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion

    Science.gov (United States)

    Lin, Lei-Lei; Dong, Yan-Min; Zong, Yao; Zheng, Qi-Shan; Fu, Yue; Yuan, Yong-Guang; Huang, Xia; Qian, Garrett; Gao, Qian-Ying

    2016-01-01

    AIM To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion (BRVO). METHODS Fifty BRVO eyes were divided into ischemic (n=26) and non-ischemic (n=24) groups, based on fundus fluorescein angiography. Healthy individuals (n=52 and n=48, respectively) were also recruited as controls for the two groups. The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups. RESULTS In the ischemic BRVO group, the occluded arterioles oxygen saturation (SaO2-A, 106.0%±14.3%), instead of the occluded venule oxygen saturation (SaO2-V, 60.8%±9.4%), showed increases when compared with those in the same quadrant vessels (SaO2-A, 86.1%±16.5%) in the contralateral eyes (Pcentral vessels showed similar trends with those of the occluded vessels. In the non-ischemic BRVO group, the occluded and central SaO2-V and SaO2-A showed no significant changes. In both the ischemic and non-ischemic BRVOs, the central SaO2-A was significantly increased when compared to healthy individuals. CONCLUSION Obvious changes in the occluded and central SaO2-A were found in the ischemic BRVO group, indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO. PMID:26949618

  11. CONTACTLESS MEASUREMENT OF KEY PARAMETERS OF LIMB VESSELS ON AN OCCLUSAL PLETHYSMOGRAPHY METHOD

    Directory of Open Access Journals (Sweden)

    V. I. Kuznetsov

    2013-01-01

    Full Text Available The purpose of this publication – to familiarize the readers with the newest achievements in the field of vision   machine   technologies   with   regard to the   occlusal   plethysmography.   The   principle   of plethysmograph work is similar to a principle of mechanical occlusal plethysmograph work, with that only a difference that working measuring environment (gas or liquid is replaced with laser labels, and fixation of change of volume is made by machine vision with the subsequent computer processing. Application of laser technologies of machine vision in future considerably simplified process of diagnostics, will allow to carry out diagnostics repeatedly and under various conditions of, for example, case of external action on the examined finiteness of the of heat, cold, physical exercise, and so, is representative of more and accurate picture of the state of blood vessels in the dynamics.

  12. Major vessel occlusion may predict subtherapeutic anticoagulation intensity and feasibility of administration of intravenous thrombolytics

    Science.gov (United States)

    Chang, Jun Young; Jung, Seunguk; Park, Hyun

    2017-01-01

    Objective We investigated the association between the presence of major vessel occlusion (MVO) and the intensity of the International Normalized Ratio (INR) in cardioembolic high-risk patients taking warfarin. We also evaluated whether the presence of MVO could predict the subtherapeutic range of INR ≤1.7 ensuring safe administration of intravenous thrombolytics. Methods The medical records of 177 cardioembolic stroke patients who were taking warfarin between April, 2008 and March, 2015 were retrospectively analyzed. Logistic regression analysis was performed to calculate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for the association between vessel occlusion and intensity of INR. To predict INR ≤1.7, decision tree analysis was performed. Results INR was inversely associated with MVO in an unadjusted model (OR, 0.36; 95% CI, 0.17–0.76), and in a model adjusted for initial NIHSS score and time from symptom onset to arrival (OR, 0.28; 95% CI, 0.11–0.73). Fifty-two of 58 (89.7%) patients with MVO had an INR ≤1.7, compared with 83 of 119 (69.7%) patients without MVO. Indication for anticoagulation agent use was dichotomized into NVAF and others, and applied to the subgroup of patients with MVO. All patients with NVAF (31/31, 100%) had INR ≤1.7, while 21 of 27 of the other patients (77.8%) had INR ≤1.7. Conclusions Low INR at presentation in cardioembolic stroke patients during anticoagulation treatment was associated with occurrence of major vessel occlusive stroke. Presence of MVO and indications for anticoagulation may be utilized to ensure the feasibility of administration of intravenous thrombolytics. PMID:28158211

  13. Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Lei-Lei Lin

    2016-01-01

    Full Text Available AIM: To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion (BRVO. METHODS: Fifty BRVO eyes were divided into ischemic (n=26 and non-ischemic (n=24 groups, based on fundus fluorescein angiography. Healthy individuals (n=52 and n=48, respectively were also recruited as controls for the two groups. The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups. RESULTS: In the ischemic BRVO group, the occluded arterioles oxygen saturation (SaO2-A, 106.0%±14.3%, instead of the occluded venule oxygen saturation (SaO2-V, 60.8%±9.4%, showed increases when compared with those in the same quadrant vessels (SaO2-A, 86.1%±16.5% in the contralateral eyes (P<0.05. The oxygen saturations of the central vessels showed similar trends with those of the occluded vessels. In the non-ischemic BRVO group, the occluded and central SaO2-V and SaO2-A showed no significant changes. In both the ischemic and non-ischemic BRVOs, the central SaO2-A was significantly increased when compared to healthy individuals. CONCLUSION: Obvious changes in the occluded and central SaO2-A were found in the ischemic BRVO group, indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO.

  14. Retinal vessel tortuosity associated with central retinal vein occlusion: an optical coherence tomography study.

    Science.gov (United States)

    Muraoka, Yuki; Tsujikawa, Akitaka; Kumagai, Kyoko; Akagi-Kurashige, Yumiko; Ogino, Ken; Murakami, Tomoaki; Miyamoto, Kazuaki; Yoshimura, Nagahisa

    2014-01-07

    We studied morphologic changes of the retinal vasculature in eyes with central retinal vein occlusion (CRVO) through the use of optical coherence tomography (OCT). Major retinal vessels in 35 eyes from 35 consecutive patients with acute CRVO were examined prospectively and longitudinally with sequential thin sectioning and circumpapillary scanning. Anteroposterior venous tortuosity associated with CRVO was quantified on longitudinal OCT images of a randomly selected major temporal vein. On OCT sections of a given vein, we identified the innermost and outermost points of the vessel wall. The degree of anteroposterior venous tortuosity was defined as the difference between the vertical distances from the retinal pigment epithelium to the center of the venous lumen at these two points. The OCT images revealed that the major retinal veins traveled tortuously through the swollen neurosensory retina from the inner retinal surface to the retinal pigment epithelium. The degree of anteroposterior venous tortuosity was correlated with poor visual acuity (r = 0.457, P = 0.017), increased mean foveal thickness (r = 0.671, P retinal detachment was detected around the optic disc, which correlated with anteroposterior venous tortuosity. In 14 (40%) eyes, elongated major retinal veins disrupted the boundary between retinal vessels and parenchyma, which resulted in juxtavenous splitting of the neurosensory retina. In eyes with CRVO, OCT can be used to visualize anteroposterior venous tortuosity and associated structural changes to the retinal parenchyma.

  15. Large Pelagic Logbook Trip Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch and effort for fishing trips that are taken by vessels with a Federal permit issued for the swordfish and sharks under the Highly...

  16. Large Pelagic Logbook Set Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch and effort for fishing trips that are taken by vessels with a Federal permit issued for the swordfish and sharks under the Highly...

  17. Detection of single-phase CTA occult vessel occlusions in acute ischemic stroke using CT perfusion-based wavelet-transformed angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, Wolfgang G.; Sommer, Wieland H.; Meinel, Felix G.; Ertl-Wagner, Birgit; Thierfelder, Kolja M. [Ludwig-Maximilian-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Havla, Lukas; Dietrich, Olaf [Ludwig-Maximilian-University Hospital Munich, Josef Lissner Laboratory for Biomedical Imaging of the Institute for Clinical Radiology, Munich (Germany); Dorn, Franziska [Ludwig-Maximilian-University Hospital Munich, Department of Neuroradiology, Munich (Germany); Buchholz, Grete [Ludwig-Maximilian-University Hospital Munich, Department of Neurology, Munich (Germany)

    2017-06-15

    To determine the detection rate of intracranial vessel occlusions using CT perfusion-based wavelet-transformed angiography (waveletCTA) in acute ischemic stroke patients, in whom single-phase CTA (spCTA) failed to detect an occlusion. Subjects were selected from a cohort of 791 consecutive patients who underwent multiparametric CT including whole-brain CT perfusion. Inclusion criteria were (1) significant cerebral blood flow (CBF) deficit, (2) no evidence of vessel occlusion on spCTA and (3) follow-up-confirmed acute ischemic infarction. waveletCTA was independently analysed by two readers regarding presence and location of vessel occlusions. Logistic regression analysis was performed to identify predictors of waveletCTA-detected occlusions. Fifty-nine patients fulfilled the inclusion criteria. Overall, an occlusion was identified using waveletCTA in 31 (52.5 %) patients with negative spCTA. Out of 47 patients with middle cerebral artery infarction, 27 occlusions (57.4 %) were detected by waveletCTA, mainly located in the M2 (15) and M3 segments (8). The presence of waveletCTA-detected occlusions was associated with larger CBF deficit volumes (odds ratio (OR) = 1.335, p = 0.010) and shorter times from symptom onset (OR = 0.306, p = 0.041). waveletCTA is able to detect spCTA occult vessel occlusions in about half of acute ischemic stroke patients and may potentially identify more patients eligible for endovascular therapy. (orig.)

  18. Characteristics of global cerebral ischemia models constructed by modified four-vessel occlusion in rats

    Institute of Scientific and Technical Information of China (English)

    Jinbao Li; Lai Jiang; Hua Xu; Yuanchang Xiong; Xiaoming Deng

    2006-01-01

    BACKGROUND: Pulsinelli et al developed a kind of rat models with four-vessel occlusion-induced global cerebral ischemia. Because the histo-pathological changes and severe cerebral ischemia reproducibility of this model are good and the stability of this model in circulation respiration is superior to that of other models, so four-vessel occlusion method has become a classic modeling method for global cerebral ischemia model. This model has been improved in some laboratories to meet different requirements in different studies. OBJECTIVE: To establish a highly reproducible rat model of reversible forebrain ischemia by modifying four-vessel occlusion model introduced by Pulsinelli et al, and to investigate its neurophysiological and pathological changes and the characteristics of modified operation. DESIGN: Completely randomized grouping, controlled trial. SETTING: Department of Anesthesiology,Changhai Hospital, Second Military Medical University of Chinese PLA. MATERIALS: A total of 65 male healthy SD rats, weighing 250-300 g, were provided by the Experimental Animal Center of Second Military Medical University of Chinese PLA. VSM hemodynamic monitor and temperature monitor (Thermal ert TH-5, U.S.A) were used.METHODS: The trial was conducted in the Department of Anesthesiology, Changhai Hospital, Second Military Medical University of Chinese PLA from January 2005 to March 2006. ① Experimental grouping: Sixty-five rats were randomly divided into the following 7 groups: sham-operation group (n =9): given the same operation, without occlusion of vessels; 5 minutes ischemia group (n =9): ischemia 5 minutes and reperfusion 72 hours; 10 minutes ischemia group (n =8): ischemia 10 minutes and reperfusion 72 hours; 15 minutes ischemia group (n =9): ischemia 15 minutes and reperfusion 72 hours; 20 minutes ischemia group (n =8): ischemia 20 minutes and reperfusion 72 hours; 30 minutes ischemia group (n =7); ischemia 30 minutes and reperfusion 72 hours; ischemia control group

  19. Modified Blalock clamp: a single-hand autostatic device for pulmonary vessel occlusion during lung cancer resection

    OpenAIRE

    Petrella, Francesco; Solli, Piergiorgio; Borri, Alessandro; Spaggiari, Lorenzo

    2011-01-01

    Vascular clamping during lung cancer resection may be difficult in patients with short vessels or large neoplasms preventing adequate and safe exposure. In addition, the physiological vicinity of some vessels to rigid structures like the bronchi may interfere with ideal clamp positioning even in ordinary procedures. We have modified the original Blalock clamp to facilitate the control of pulmonary vessels and physiologically compress the vessel walls, thereby allowing optimal vascular resecti...

  20. EULAR recommendations for the management of large vessel vasculitis

    NARCIS (Netherlands)

    Mukhtyar, C.; Guillevin, L.; Cid, M. C.; Dasgupta, B.; de Groot, K.; Gross, W.; Hauser, T.; Hellmich, B.; Jayne, D.; Kallenberg, C. G. M.; Merkel, P. A.; Raspe, H.; Salvarani, C.; Scott, D. G. I.; Stegeman, C.; Watts, R.; Westman, K.; Witter, J.; Yazici, H.; Luqmani, R.

    Objectives: To develop European League Against Rheumatism (EULAR) recommendations for the management of large vessel vasculitis. Methods: An expert group (10 rheumatologists, 3 nephrologists, 2 immunolgists, 2 internists representing 8 European countries and the USA, a clinical epidemiologist and a

  1. Cavitation distribution within large phantom vessel and mechanical damage formed on surrounding vessel wall.

    Science.gov (United States)

    Qiao, Yangzi; Yin, Hui; Li, Zhaopeng; Wan, Mingxi

    2013-11-01

    Blood vessel is one of the most important targets encountered during focused ultrasound (FU) therapy. The lasting high temperature caused by continuous FU can result in structural modification of small vessel. For the vessel with a diameter larger than 2mm, convective cooling can significantly weaken the thermal effect of FU. Meanwhile, the continued presence of ultrasound will cause repetitive cavitation and acoustic microstreaming, making comprehension of continuous wave induced cavitation effect in large vessels necessary. The Sonoluminescence (SL) method, mechanical damage observation and high-speed camera were used in this study to investigate the combination effect of ultrasound contrast agents (UCAs) and continuous FU in large phantom vessels with a diameter of 10mm without consideration of thermal effect. When the focus was positioned at the proximal wall, cylindrical hole along the acoustic axis opposite the ultrasound wave propagation direction was observed at the input power equal to or greater than 50 W. When the focus was located at the distal wall, only small tunnels can be found. The place where the cylindrical hole formed was corresponding to where bubbles gathered and emitted brilliant light near the wall. Without UCAs neither such bright SL nor cylindrical hole can be found. However, the UCAs concentration had little influence on the SL distribution and the length of cylindrical hole. The SL intensity near the proximal vessel wall and the length of the cylindrical hole both increased with the input power. It is suggested that these findings need to be considered in the large vessel therapy and UCAs usage.

  2. Central retinal vessel blood flow after surgical treatment for central retinal vein occlusion.

    NARCIS (Netherlands)

    Crama, N.; Gualino, V.; Restori, M.; Charteris, D.G.

    2010-01-01

    PURPOSE: The purpose of this study was to determine the effect of radial optic neurotomy and retinal endovascular surgery on retinal blood flow velocity in patients with central retinal vein occlusion. METHODS: A prospective interventional case series. RESULTS: Six patients with a central retinal

  3. Central retinal vessel blood flow after surgical treatment for central retinal vein occlusion.

    Science.gov (United States)

    Crama, Niels; Gualino, Vincent; Restori, Marie; Charteris, David G

    2010-01-01

    The purpose of this study was to determine the effect of radial optic neurotomy and retinal endovascular surgery on retinal blood flow velocity in patients with central retinal vein occlusion. A prospective interventional case series. Six patients with a central retinal vein occlusion of retinal endovascular surgery. Five patients had decreased central venous blood flow velocity compared with the fellow eye, and one patient had similar central venous blood flow in both eyes at baseline. All study eyes had decreased central venous blood flow velocity compared with the fellow eye at 24 weeks after treatment. Two patients had a further decrease in central venous blood flow during the study. Three patients had no minimal change in central venous blood flow, and 1 patient showed a minimal increase from 3 cm/s at baseline to 4 cm/s 24 weeks after surgery. Radial optic neurotomy and retinal endovascular surgery do not alter central retinal blood flow velocity. The place of these therapies in the treatment for central retinal vein occlusion should be questioned.

  4. Vasculites dos médios e grandes vasos Medium and large vessel vasculitis

    Directory of Open Access Journals (Sweden)

    Hebert Roberto Clivati Brandt

    2009-02-01

    Full Text Available As vasculites são constituídas por um grande grupo de síndromes caracterizadas por inflamação e necrose da parede dos vasos sangüíneos, resultando em estreitamento ou oclusão do lúmen. A distribuição dos vasos envolvidos varia consideravelmente e serve de base para a classificação das síndromes vasculíticas: grandes vasos (arterite de Takayasu, arterite temporal; pequenos e médios vasos (poliarterite nodosa, síndrome de Churg-Strauss, granulomatose de Wegener, vasculites nas doenças reumáticas; e pequenos vasos (vasculite de hipersensibilidade, púrpura de Henoch-Schonlein, poliangeíte microscópica, crioglobulinemia. Este artigo revisa as vasculites dos médios e grandes vasos e opções terapêuticas atuais; além de oferecer orientação sobre abordagem diagnóstica e tratamento dos pacientes com suspeita de vasculite cutânea.Vasculitis comprises a broad group of syndromes characterized by inflammation and necrosis on the walls of blood vessels, resulting in narrowing or occlusion of the lumen. The distribution of involved blood vessel varies considerably and serves as the basis for one classification of vasculitic syndromes: large vessels (Takayasu arteritis, giant cell arteritis; medium and small muscular arteries (polyarteritis nodosa, Churg-Strauss syndrome, Wegener's granulomatosis, vasculitis in rheumatic diseases; and small vessels ("hypersensitivity" vasculitis, Henoch-Schonlein purpura, microscopic polyangiitis, cryoglobulinemia. This article reviews medium and large vessel vasculitis and current treatment options; it also presents a comprehensive approach to diagnosing and treating patients with suspected cutaneous vasculitis.

  5. Clinical Scales Do Not Reliably Identify Acute Ischemic Stroke Patients With Large-Artery Occlusion.

    Science.gov (United States)

    Turc, Guillaume; Maïer, Benjamin; Naggara, Olivier; Seners, Pierre; Isabel, Clothilde; Tisserand, Marie; Raynouard, Igor; Edjlali, Myriam; Calvet, David; Baron, Jean-Claude; Mas, Jean-Louis; Oppenheim, Catherine

    2016-06-01

    It remains debated whether clinical scores can help identify acute ischemic stroke patients with large-artery occlusion and hence improve triage in the era of thrombectomy. We aimed to determine the accuracy of published clinical scores to predict large-artery occlusion. We assessed the performance of 13 clinical scores to predict large-artery occlusion in consecutive patients with acute ischemic stroke undergoing clinical examination and magnetic resonance or computed tomographic angiography ≤6 hours of symptom onset. When no cutoff was published, we used the cutoff maximizing the sum of sensitivity and specificity in our cohort. We also determined, for each score, the cutoff associated with a false-negative rate ≤10%. Of 1004 patients (median National Institute of Health Stroke Scale score, 7; range, 0-40), 328 (32.7%) had an occlusion of the internal carotid artery, M1 segment of the middle cerebral artery, or basilar artery. The highest accuracy (79%; 95% confidence interval, 77-82) was observed for National Institute of Health Stroke Scale score ≥11 and Rapid Arterial Occlusion Evaluation Scale score ≥5. However, these cutoffs were associated with false-negative rates >25%. Cutoffs associated with an false-negative rate ≤10% were 5, 1, and 0 for National Institute of Health Stroke Scale, Rapid Arterial Occlusion Evaluation Scale, and Cincinnati Prehospital Stroke Severity Scale, respectively. Using published cutoffs for triage would result in a loss of opportunity for ≥20% of patients with large-artery occlusion who would be inappropriately sent to a center lacking neurointerventional facilities. Conversely, using cutoffs reducing the false-negative rate to 10% would result in sending almost every patient to a comprehensive stroke center. Our findings, therefore, suggest that intracranial arterial imaging should be performed in all patients with acute ischemic stroke presenting within 6 hours of symptom onset. © 2016 American Heart Association

  6. Assessment of whipping and springing on a large container vessel

    Directory of Open Access Journals (Sweden)

    Barhoumi Mondher

    2014-06-01

    Full Text Available Wave induced vibrations increase the fatigue and extreme loading, but this is normally neglected in design. The industry view on this is changing. Wave induced vibrations are often divided into springing and whipping, and their relative contribution to fatigue and extreme loading varies depending on ship design. When it comes to displacement vessels, the contribution from whipping on fatigue and extreme loading is particularly high for certain container vessels. A large modern design container vessel with high bow flare angle and high service speed has been considered. The container vessel was equipped with a hull monitoring system from a recognized supplier of HMON systems. The vessel has been operating between Asia and Europe for a few years and valuable data has been collected. Also model tests have been carried out of this vessel to investigate fatigue and extreme loading, but model tests are often limited to head seas. For the full scale measurements, the correlation between stress data and wind data has been investigated. The wave and vibration damage are shown versus heading and Beaufort strength to indicate general trends. The wind data has also been compared to North Atlantic design environment. Even though it has been shown that the encountered wind data has been much less severe than in North Atlantic, the extreme loading defined by IACS URS11 is significantly exceeded when whipping is included. If whipping may contribute to collapse, then proper seamanship may be useful in order to limit the extreme loading. The vibration damage is also observed to be high from head to beam seas, and even present in stern seas, but fatigue damage in general is low on this East Asia to Europe trade.

  7. Studies on the effect of administration of DDAVP in patients with cerebrovascular occlusive diseases from the viewpoint of blood coagulation-fibrinolysis in vessel walls

    OpenAIRE

    Arai, Hiroyuki; Miyakawa, Teruo; Sakuragawa, Nobuo

    1985-01-01

    To clarify the pathogenesis of cerebral thrombosis and to estimate the effectiveness of fibrinolytic treatment by administration of urokinase from the viewpoint of coagulation-fibrinolysis in vessel walls, changes of blood coagulation were investigated by intravenous administration of 1-deamino-8-D-arginine vasopressin (DDAVP) to 10 healthy volunteers and to 14 patients with cerebrovascular occlusive diseases. Results were as follows: 1) After the administration of DDAVP to normal controls, a...

  8. Effects on vessel measurement accuracy and subsequent occlusion after calcium channel blocker infusion during treatment of cerebral aneurysms with the Pipeline embolization device.

    Science.gov (United States)

    Alexander, M D; Nicholson, A D; Darflinger, R J; Settecase, F; Cooke, D L; Dowd, C F; Amans, M R; Higashida, R T; Hetts, S W; Halbach, V V

    2017-02-01

    Introduction/Purpose To achieve aneurysm occlusion, flow diverters (FDs) must be accurately sized to maximize coverage over the neck and induce thrombosis. Catheterization for diagnostic angiography can cause vasospasm that may affect vessel measurements. This study evaluates impacts of intra-arterial infusion of a calcium channel blocker (CCB) on angiographic measurements in patients treated with FDs to determine effects on final diameter of the FD and subsequent occlusion. Materials and methods Pre-treatment measurements were recorded for diameter of the distal and proximal landing zones and maximum and minimum diameters between these segments. Post-treatment measurements of the stent following deployment were recorded at these locations. When CCB was infused, post-infusion pre-treatment measurements were recorded. Rates of occlusion were noted for all patients. T-tests were performed to assess for differences in pre- and post-treatment measurements and rates of occlusion between groups with and without CCB infusion. Results Twenty-eight FDs were deployed to treat 25 aneurysms in 24 patients. CCB infusion was performed prior to deployment of 12 (42.9%) devices. No significant difference was noted between groups for pre- and post-treatment measurement changes. Confirmed aneurysm occlusion was more likely to occur in the CCB infusion group (88.9% vs. 36.4%, p = 0.009). Conclusion Optimization of device sizing is important to increase FD density over the aneurysm neck and promote thrombosis. To improve measurement accuracy, CCB infusion can reduce effects of mild vasospasm. Subsequent aneurysm occlusion was more likely to occur following FD treatment when device size selection was based on measurements performed following CCB infusion.

  9. Parent vessel occlusion for traumatic pseudoaneurysm of P3 segment of posterior cerebral artery:A case report and review of literatures

    Institute of Scientific and Technical Information of China (English)

    Xu Gaofeng; Xie Wanfu; Li Ruichun; Wang Maode

    2011-01-01

    Traumatic intracranial pseudoaneurysms (TIPA) are rare and pseudoaneurysm of P3 segment of the posterior cerebral artery (PCA) is extremely rarely reported. A 27-year-old man suffered from blunt head injury and underwent diagnostic procedure with head CT scans,cerebral CT angiograms (CTA) and digital subtraction angiograms (DSA). An abnormal high-density lesion was detected at the left side of quadrigeminal cistern and a pseudoaneurysm showed at the P3 segment of PCA. The pseudoaneurysm was successfully treated with parent artery occlusion (PAO). Making an exact preoperative diagnosis of traumatic intracranial pseudoaneurysms is of great importance. Endovascular techniques allow a safe approach to complex intracranial lesion,so endovascular management of PCA pseudoaneurysms becomes safe and effective. However,the pseudoaneurysm may not be amenable to coil placement under some conditions,thus,occlusion of the parent vessel may be a preferable treatment.

  10. Calibrating a large slab vessel: A battle of the bulge

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, I.R. [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States). Safeguards and Security Section

    1993-12-31

    The accurate measurement of volume in slab vessels can be difficult because slab vessels expand--in spite of internal or external supports--as they are filled. One form of bulging is elastic deflection, a gradual expansion of the vessel wall resulting from an increased weight of contained solution. As part of an upgrade to the Idaho Chemical Processing Plant, slab tanks were proposed as accountability measurement vessels. A 1960 liter slab tank prototype was set up for preliminary calibrations. Two series of calibrations were conducted: the first using water, and the second using aluminum nitrate. It was conjectured that the increased weight of aluminum nitrate would cause the vessel walls to deflect more than they did for an equal level of water, resulting in a greater volume. As expected, a significant expansion was observed with the aluminum nitrate, but some of the deflection proved to be permanent rather than elastic. The consequence is that considerably more effort will be required to calibrate slab vessels for uranium accountability. Not only must a calibration curve (or family of curves) be developed giving volume as a function of both liquid level and density, but, if possible, a determination must be made as to when the deflection is no longer temporary.

  11. Collateral vessel presence in branch and central retinal vein occlusions and their impact on visual acuity and anatomical gains: a retrospective analysis.

    Science.gov (United States)

    Singh, Rishi P; Lee, Tamara J; Yau, Linda; Rubio, Roman G

    2014-11-01

    To evaluate the incidence of collateral vessel formation and to determine their impact on best-corrected visual acuity and central foveal thickness in patients with branch or central retinal vein occlusion (BRVO, CRVO) receiving 0.3 mg or 0.5 mg of ranibizumab, or sham. This retrospective analysis was performed in patients with macular edema secondary to retinal vein occlusion who received 6 monthly intravitreal injections of ranibizumab (0.3 mg or 0.5 mg), or sham, followed by 6 months of as-needed treatment. Collateral vessel presence, change from baseline best-corrected visual acuity, and change from baseline central foveal thickness were assessed at baseline and months 3, 6, 9, and 12. At month 12, 19.6% of BRVO patients receiving sham/0.5 mg and 16.7% receiving ranibizumab (0.3 mg and 0.5 mg pooled) manifested collaterals at the disk, whereas 48.2% and 47.2% displayed collaterals within the retina, respectively. In CRVO patients, 57.9% and 59.2% of all groups manifested collaterals on the disk, respectively, whereas 12.1% and 15.1% displayed collaterals within the retina. Mean best-corrected visual acuity gain in ranibizumab-treated BRVO and CRVO patients was similar, irrespective of collaterals within the retina ( P > 0.05; CRVO: P > 0.05). The location of collaterals differed between retinal vein occlusion subtypes and ranibizumab treatment did not affect collateral vessel incidence. The presence of collaterals did not seem to impact best-corrected visual acuity gains at month 12 in both BRVO and CRVO patients receiving ranibizumab, whereas generally greater central foveal thickness reductions were observed with presence of collaterals in BRVO patients.

  12. Calibrating a large slab vessel: A battle of the bulge

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, I.R.

    1993-10-01

    Slab tanks (critically-safe-by-geometry vessels) were proposed for the storage of concentrated, highly-enriched uranium solution in the design of the Fuel Processing Restoration (FPR) Facility at the Idaho Chemical Processing Plant (ICPP). Currently, measurements of bulk mass in ICPP annular vessels have standard deviations on the order of 0.2%, or less. ICPP personnel felt that their inexperience with the aforementioned expansions would prevent them from attaining comparable precision with slab tanks. To help assess the measurement accuracy of slab vessels, a full-scale mockup of those proposed for the FPR Facility was installed for test calibrations. These calibrations were designed to detect vessel expansion under differing conditions. This paper will compare the base-line, water calibrations with those of the higher-density aluminum nitrate, and any observed deflection will be described using vessel calibration techniques. The calibration using water at an elevated temperature was not performed due to the difficulty of maintaining the elevated temperature. This calibration probably will not be conducted because the construction of the FPR Facility has been halted.

  13. Hydrogel based occlusion systems

    OpenAIRE

    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 target occlusion location. The hydrogel is configured to permanently occlude the target occlusion location in the swollen state. The hydrogel may be an electro-activated hydrogel (EAH) which could be ...

  14. 46 CFR 356.47 - Special requirements for large vessels.

    Science.gov (United States)

    2010-10-01

    ... 356.47 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION MISCELLANEOUS REQUIREMENTS FOR... accordance with the American Fisheries Act of 1998, Title II, Division C, Public Law 105-277, to allow such... Fisheries Council or the Gulf of Mexico Fisheries Council. (e) The owner of a vessel that meets any of the...

  15. Large deep infarcts found in proximal middle cerebral artery steno-occlusive disease: MRI and angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Bum Ha; Kim, Eui Jong; Choi, Woo Suk; Jang, Dae Il; Chung, Kyung Cheon; Oh, Joo Hyung; Yoon, Yup; Hong, Hoon Pyo [Kyunghee Univ. Hospital, Seoul (Korea, Republic of)

    1998-11-01

    To determine the nature of large deep-seated infarcts without cortical infarct in patients with steno-occlusive disease of the proximal middle cerebral artery (MCA) using magnetic resonance images (MRI) and angiography. By means of MRI and MR angiography (MRA), we examined 24 patients with large deep cerebral infarctions (>3cm in size) involving the basal ganglia, corona radiata and/or centrum semiovale, as well as steno-occlusive lesion of the proximal MCA. According to location, infarctions were classified into five groups, as follows:Group 1:basal ganlgia and corona radiata; 2:basal ganglia, corona radiata and centrum semiovale;3:corona radiata and centrum semiovale;4:corona radiata;5:basal ganglia only. We evaluated the topography of the lesions and correlated the results with the findings of angiography (all 24 MRA;the 13:conventional angiography). Involvement of the head of the caudate nucleus and the internal capsule were also evaluated. Fifteen of 24 cases (63%) were assigned to group 1 (4 proximal MCA(M1) occlusion and 11 stenosis), and five of 24 (21%) with M1 occlusions to group 2. Group 3 comprised only one case with M1 occlusion. Two cases with both occlusion and stenosis were included in group 4, and only one case-with M1 stenosis-in group 5. Infarctions at the caudate nucleus were seen in five cases, and at the internal capsule in two. On conventional angiography (13 cases) cortical branches of the MCA were delineated through the leptomeningeal collaterals of anterior or posterior cerebral arteries. Most large deep cerebral infarctions found in proximal MCA diseases are thought to extend cephalad to the corona radiata. When large deep-seated infarctions with proximal MCA occlusion is observed more frequently than stenosis.=20.

  16. Association between proximal internal carotid artery steno-occlusive disease and diffuse wall thickening in its petrous segment: a magnetic resonance vessel wall imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaoyi; Li, Dongye [Capital Medical University and Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Beijing (China); Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Zhao, Huilin [Shanghai Jiao Tong University, Department of Radiology, Renji Hospital, School of Medicine, Shanghai (China); Chen, Zhensen; Qiao, Huiyu; He, Le; Li, Rui [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Cui, Yuanyuan [PLA General Hospital, Department of Radiology, Beijing (China); Zhou, Zechen [Philips Research China, Healthcare Department, Beijing (China); Yuan, Chun [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); University of Washington, Department of Radiology, Seattle, WA (United States); Zhao, Xihai [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Beijing Institute for Brain Disorders, Center for Stroke, Beijing (China)

    2017-05-15

    Significant stenosis or occlusion in carotid arteries may lead to diffuse wall thickening (DWT) in the arterial wall of downstream. This study aimed to investigate the correlation between proximal internal carotid artery (ICA) steno-occlusive disease and DWT in ipsilateral petrous ICA. Symptomatic patients with atherosclerotic stenosis (>0%) in proximal ICA were recruited and underwent carotid MR vessel wall imaging. The 3D motion sensitized-driven equilibrium prepared rapid gradient-echo (3D-MERGE) was acquired for characterizing the wall thickness and longitudinal extent of the lesions in petrous ICA and the distance from proximal lesion to the petrous ICA. The stenosis degree in proximal ICA was measured on the time-of-flight (TOF) images. In total, 166 carotid arteries from 125 patients (mean age 61.0 ± 10.5 years, 99 males) were eligible for final analysis and 64 showed DWT in petrous ICAs. The prevalence of severe DWT in petrous ICA was 1.4%, 5.3%, 5.9%, and 80.4% in ipsilateral proximal ICAs with stenosis category of 1%-49%, 50%-69%, 70%-99%, and total occlusion, respectively. Proximal ICA stenosis was significantly correlated with the wall thickness in petrous ICA (r = 0.767, P < 0.001). Logistic regression analysis showed that proximal ICA stenosis was independently associated with DWT in ipsilateral petrous ICA (odds ratio (OR) = 2.459, 95% confidence interval (CI) 1.896-3.189, P < 0.001). Proximal ICA steno-occlusive disease is independently associated with DWT in ipsilateral petrous ICA. (orig.)

  17. Aortoiliac occlusive disease masquerading as cerebrovascular accident

    Directory of Open Access Journals (Sweden)

    Nandeesh B

    2007-01-01

    Full Text Available Acute aortoiliac occlusion is an unusual but potentially catastrophic condition causing acute limb ischemia and associated with early and high rates of mortality and morbidity. It is caused by either embolic occlusion of the infra renal aorta at the bifurcation or beyond or thrombosis of the abdominal aorta and its large terminal branches. Neurological symptoms are rare manifestation of acute aortoiliac occlusion and when neurological symptoms predominate, patients are mistakenly considered to have cerebrovascular event. We present a 60-year-old man with atherosclerotic thrombotic occlusion of the left common iliac artery causing acute painful monoplegia. We mistook the acute monoplegia due to acute limb ischemia for cerebrovascular accident. Pathologic examination revealed a firm thrombus occluding the origin of left common iliac artery and extending along the length of the vessel. Acute aortic iliac occlusion can masquerade as a cerebrovascular stroke and a thorough clinical evaluation and imaging studies allow early diagnosis and instituting life-saving treatment timely.

  18. Altered low frequency oscillations of cortical vessels in patients with cerebrovascular occlusive disease – a NIRS study

    DEFF Research Database (Denmark)

    Phillip, Dorte; Iversen, Helle K; Schytz, Henrik W

    2013-01-01

    Analysis of cerebral autoregulation by measuring spontaneous oscillations in the low frequency spectrum of cerebral cortical vessels might be a useful tool for assessing risk and investigating different treatment strategies in carotid artery disease and stroke. Near infrared spectroscopy (NIRS...

  19. View synthesis from wide-baseline views using occlusion aware estimation of large disparities

    Science.gov (United States)

    Elliethy, Ahmed S.; Aly, Hussein A.; Sharma, Gaurav

    2014-03-01

    Accurate disparity estimation is a key ingredient required when generating a high fidelity novel view from a set of input views. In this paper, a high quality disparity estimation method is proposed for view synthesis from multiple input images with large disparities and occlusions. The method optimally selects one out of three image pairs to estimate the disparity map for different regions of the novel view. The novel view is then formed using this disparity map. We introduce two novel elements: a) an enhanced visibility map that is able to segment the scene accurately near object boundaries and b) a backward unilateral and bilateral disparity estimation procedure using the Gabor transform on an expandable search window to tackle large disparities. The quality of the interpolated virtual views produced by the proposed method is assessed and compared against two of the prominent previously-reported methods. The proposed method offers a significant improvement both in terms of visual quality of the interpolated views as well as the peak signal-to-noise ratio (PSNR) and structured similarity image index (SSIM) metrics.

  20. Optic chiasm compression from mass effect and thrombus formation following unsuccessful treatment of a giant supraclinoid ICA aneurysm with the Pipeline device: open surgical bailout with STA-MCA bypass and parent vessel occlusion.

    Science.gov (United States)

    Abla, Adib A; Zaidi, Hasan A; Crowley, R Webster; Britz, Gavin W; McDougall, Cameron G; Albuquerque, Felipe C; Spetzler, Robert F

    2014-07-01

    Pipeline Embolization Devices (PEDs) have been shown to be effective for intracranial internal carotid artery (ICA) aneurysms, and are now approved by the FDA specifically for this use. Potential pitfalls, however, have not yet been described in the pediatric neurosurgical literature. The authors report on a 10-year-old boy who presented to the Barrow Neurological Institute after progressive visual decline. He had undergone placement of a total of 7 telescoping PEDs at another facility for a large ICA aneurysm. Residual filling of the aneurysm and significant expansion of intraaneurysmal thrombus with chiasmal compression on admission images were causes for concern. The patient underwent a surgical bailout with a superficial temporal artery-middle cerebral artery bypass, with parent artery occlusion. Postoperative vascular imaging was notable for successful occlusion of the parent vessel, with no evidence of filling of the aneurysm. Reports on the pitfalls of PEDs in the neurosurgical literature are scarce. To the authors' knowledge this represents the first paper describing a successful open surgical bailout for residual aneurysmal filling and expansion of thrombus after placement of a PED.

  1. Observation and analysis of high-speed human motion with frequent occlusion in a large area

    Science.gov (United States)

    Wang, Yuru; Liu, Jiafeng; Liu, Guojun; Tang, Xianglong; Liu, Peng

    2009-12-01

    The use of computer vision technology in collecting and analyzing statistics during sports matches or training sessions is expected to provide valuable information for tactics improvement. However, the measurements published in the literature so far are either unreliably documented to be used in training planning due to their limitations or unsuitable for studying high-speed motion in large area with frequent occlusions. A sports annotation system is introduced in this paper for tracking high-speed non-rigid human motion over a large playing area with the aid of motion camera, taking short track speed skating competitions as an example. The proposed system is composed of two sub-systems: precise camera motion compensation and accurate motion acquisition. In the video registration step, a distinctive invariant point feature detector (probability density grads detector) and a global parallax based matching points filter are used, to provide reliable and robust matching across a large range of affine distortion and illumination change. In the motion acquisition step, a two regions' relationship constrained joint color model and Markov chain Monte Carlo based joint particle filter are emphasized, by dividing the human body into two relative key regions. Several field tests are performed to assess measurement errors, including comparison to popular algorithms. With the help of the system presented, the system obtains position data on a 30 m × 60 m large rink with root-mean-square error better than 0.3975 m, velocity and acceleration data with absolute error better than 1.2579 m s-1 and 0.1494 m s-2, respectively.

  2. Incidentally diagnosed Takayasu arteritis on thyroid ultrasonography showing prominent collateral vessels of thyroidal arteries and common carotid artery occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Se Jin; Kim, Eun Kyung [Dept. of Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2014-10-15

    We report a case of middle-aged woman incidentally diagnosed with Takayasu arteritis during the ultrasonography of a thyroid gland nodule. Prominent collaterals of the thyroidal arteries and a thin common carotid artery with mural thickening and deficient intraluminal flow signals were initially depicted on the ultrasonography with color Doppler. Subsequent magnetic resonance angiography and computed tomography aortography confirmed the diagnosis with the imaging features of a bilateral long segment common carotid artery occlusion and segmental stenosis of the left subclavian artery in addition to the suggestive physical findings.

  3. In vivo experiments and numerical investigations on nanocryosurgical freezing of target tissues with large blood vessels.

    Science.gov (United States)

    Sun, Zi-Qiao; Yang, Yang; Liu, Jing

    2012-02-01

    This study presented the first in vivo animal experiments of using nano-cryosurgical modality to completely freezing tumor tissues embedded with large blood vessels, which is a tough issue to tackle otherwise. Three-dimensional theoretical simulations were also performed on the complex freezing problems by considering flow and heat transfer of blood flow in large vessels. According to the experimental measurements and numerical predictions, injecting the nanoparticles with high thermal conductivity into the freezing target can significantly reduce the heating effect of blood vessel, shorten the freezing time, and enlarge the freezing range. Most importantly, the introduction of nanoparticles successfully overcomes the classical challenges in completely ablating the tumor region with large blood vessel and enhancing the freezing efficacy of cryosurgery. This investigation consolidates the practical and theoretical foundation for nano-cryosurgery which suggests a highly efficient freezing strategy for treating late stage tumor.

  4. 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 tar

  5. Varicella Zoster Virus and Large Vessel Vasculitis, the Absence of an Association

    Directory of Open Access Journals (Sweden)

    Gary W. Procop

    2017-06-01

    Full Text Available Objective: It is controversial whether microorganisms play a role in the pathogenesis of large and medium vessel vasculitides (eg, giant cell arteritis [GCA], Takayasu arteritis [TAK] and focal idiopathic aortitis [FIA]. Recent studies have reported the presence of Varicella Zoster Virus (VZV within formalin-fixed, paraffin-embedded temporal arteries and aortas of about three-quarters or more of patients with these conditions, and in a minority of controls. In a prospective study, we sought to confirm these findings using DNA extracted from vessels that were harvested under surgically aseptic conditions and snap frozen. Methods and Results: DNA samples extracted from 11 surgically sterile temporal arteries and 31 surgically sterile thoracic aortas were used in an attempt to identify the vessel-associated VZV genome. Two different validated PCR methods were used. Thirty-one thoracic aorta aneurysm specimens included biopsies from 8 patients with GCA, 2 from patients with TAK, 6 from patients with FIA, and 15 from patients without vasculitis, who had non-inflammatory aneurysms. Eleven temporal artery biopsies were collected from 5 patients with GCA and 6 controls. The presence of VZV was not identified in either the specimens from patients with large vessel vasculitis or from the controls. Conclusions: Using surgically sterile snap-frozen specimens, we were unable to confirm recent reports of the presence of VZV in either aortas or temporal arteries from patients with large vessel vasculitis or controls. Keywords: Aorta and temporal artery biopsies, Varicella Zoster Virus, Large Vessel Vasculitis

  6. Migratory large vessel vasculitis preceding acute myeloid leukemia: a case report.

    Science.gov (United States)

    Chandratilleke, Dinusha; Anantharajah, Anthea; Vicaretti, Mauro; Benson, Warwick; Berglund, Lucinda J

    2017-03-16

    Large vessel vasculitis is a rare disorder usually occurring in the context of the autoimmune conditions of giant cell arteritis and Takayasu's arteritis. Case reports have described large vessel vasculitis occurring in individuals with myelodysplastic syndrome, preceding transformation to acute myeloid leukemia. A 56-year-old Afghanistan-born woman presented with fever, a tender left carotid artery, and raised inflammatory markers. Computed tomography revealed thickening of the wall of her left carotid artery. Her symptoms resolved spontaneously; however, they recurred weeks later on the contralateral side, along with abdominal pain after eating. Further imaging with computed tomography and positron emission tomography demonstrated resolution of her left carotid artery abnormality, but new wall thickening and inflammation in her right carotid artery, abdominal aorta, and superior mesenteric artery. She was diagnosed as having large vessel vasculitis, which resolved with corticosteroids and methotrexate. Five months later, she developed acute myeloid leukemia. She had no known history of myelodysplastic syndrome at the time of diagnosis with vasculitis. Large vessel vasculitis in older individuals presenting with atypical clinical features, such as a migratory pattern of affected vessels, vessel wall tenderness, and marked systemic inflammation, should prompt a search for underlying myelodysplasia. Clinicians should be vigilant for progression to acute myeloid leukemia.

  7. Computational study of thermal effects of large blood vessels in human knee joint.

    Science.gov (United States)

    Xue, Xu; He, Zhi Zhu; Liu, Jing

    2013-01-01

    This paper is dedicated to present a comprehensive investigation on the thermal effects of large blood vessels of human knee joint during topical cooling and fomentation treatment. A three-dimensional (3D) finite element analysis by taking full use of the anatomical CAD model of human knee joint was developed to accurately simulate the treatment process. Based on the classical Pennes bio-heat transfer equation, the time evolution of knee joint's temperature distribution and heat flux from large blood vessels was obtained. In addition, we compared several influencing factors and obtained some key conclusions which cannot be easily acquired through clinical experiments. The results indicated that the thermal effects of large blood vessels could remarkably affect the temperature distribution of knee joint during treatment process. Fluctuations of blood flow velocity and metabolic heat production rate affect little on the thermal effects of large blood vessels. Changing the temperature of blood and regimes of treatment could effectively regulate this phenomenon, which is important for many physiological activities. These results provide a guideline to the basic and applied research for the thermally significant large blood vessels in the knee organism.

  8. Large-scale Vacuum Vessel Design and Finite Element Analysis

    Institute of Scientific and Technical Information of China (English)

    WANG Wenlong; CAI Guobiao; ZHOU Jianping

    2012-01-01

    The vacuum plume effects experimental system (PES) is the first experimental system designed to study the effects of vacuum plume in China.The main equipment,a vacuum chamber of 5.5 m in diameter and 12.8 m in length,and structure design of hinged door are described.The finite element method (FEM) is adopted to analyze the static strength and stability of the PES vacuum chamber.It is demonstrated that the static strength and stability are qualified.For the 5.5 m diameter vacuum chamber door,three design schemes are put forward.After comparisons are made,the single-axis-double-pin hinged door is selected.The FEM is applied to checking its static strength as well as distortions.The results show that the door's distortion and displacement change mainly due to the gravity of the door which leads to its sinking.The calculated displacement is less than 7.8 mm,while the actual measurement is 5 mm.The single-axis-double-pin hinged door mechanism completely satisfies the design requirements.This innovative structure can be introduced as a reference for the design of large-scale hinged doors.

  9. Ligation of an unusually large vessel during maxillary sinus floor augmentation. A case report.

    Science.gov (United States)

    Testori, Tiziano; Rosano, Gabriele; Taschieri, Silvio; Del Fabbro, Massimo

    2010-01-01

    The purpose of the present case report was to document a maxillary sinus floor augmentation procedure involving ligation of a blood vessel with a nearly 3-mm diameter in the lateral wall of the maxillary sinus. A bilateral maxillary sinus floor augmentation procedure was performed in a 51-year-old healthy man. The preoperative computed tomography scan revealed a bony canal within the lateral maxillary sinus wall of the right as well as the left side close to the alveolar ridge. A vessel with a diameter of nearly 3 mm was identified during the sinus floor augmentation on the left side. The vessel was exposed and ligated. A vessel with a diameter of approximately 1 mm was identified on the right side and the sinus floor augmentation was performed without ligation. No complications were observed and the postoperative healing was uneventful. Although accidental laceration of vessels with an unusually large diameter during maxillary sinus floor augmentation is not life-threatening, impaired visualisation may compromise the augmentation procedure, including the elevation of the Schneiderian membrane. Moreover, postoperative bleeding and formation of a haematoma may occur. Therefore, ligation of vessels with an unusually large diameter is recommended during maxillary sinus floor augmentation to minimise intra- and postoperative complications.

  10. [Successful treatment with azacitidine for myelodysplastic syndrome with large vessel vasculitis].

    Science.gov (United States)

    Mishima, Mai; Makita, Masanori; Sando, Yasuhisa; Yamamoto, Yoshikazu; Shiote, Yasuhiro; Hara, Yoshitaka; Yamamoto, Kazuhiko; Imajo, Kenji

    2015-01-01

    Paraneoplastic inflammation of the large vessels is a rare complication of myelodysplastic syndrome (MDS), and patients with MDS and systemic vasculitis have a poor prognosis. We present a 66-year-old male with MDS and large vessel vasculitis treated with azacitidine. Azacitidine administration improved his clinical symptoms, high fever and thickening of the arterial wall, and he achieved a complete bone marrow remission. However, 1 year later he showed progression of MDS. For MDS with vasculitis, intensive therapy, the same as that given to the high-risk group, should be considered and azacitidine administration may represent an efficacious treatment.

  11. Hull Girder Fatigue Damage Estimations of a Large Container Vessel by Spectral Analysis

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2013-01-01

    This paper deals with fatigue damage estimation from the analysis of full-scale stress measurements in the hull of a large container vessel (9,400 TEU) covering several months of operation. For onboard decision support and hull monitoring sys-tems, there is a need for a fast reliable method...

  12. An instrument to measure the convective heat transfer coefficient on large vessels.

    Science.gov (United States)

    Miguel, Alaor Faria; de O Nascimento, Francisco Assis; da Rocha, Adson Ferreira; dos Santos, Icaro

    2008-01-01

    Hepatocellular carcinoma is one of the most common malignancies worldwide. During radiofrequency hepatic ablation, the tumor is heated by means of radiofrequency energy. The heating causes necrosis of the malignant tumor. Thus, if the procedure is successful it can cure the patient. Studies have shown that recurrences occur after the treatment and these recurrences frequently take place next to the hepatic artery and portal vein. The recurrences occur due to the high convective loss on these vessels. This work proposed, developed and tested an instrument for the measurement of the convective heat transfer coefficient (h) in large vessels. Moreover, this work developed a mechanical simulator and validated an equation developed by Consiglieri et al, which analytically determines the value of h. The instrument was tested using a mechanical simulator that reproduces the flow conditions and the geometry of large vessels in the liver. A flow velocity of 0.2 m/s was simulated in order to mock the typical flow at the portal vein. The average value of h using the experimental apparatus was 2130+/-40 W.m(-2).K(-1) (mean+/-SD). The results showed that the error of the proposed method is approximately 22%. This work showed that the instrument can be used for measuring h in vitro and that the Consiglieri's equation can be used to determine the convective heat transfer coefficient on large vessels.

  13. HydroCoils, occlusion rates, and outcomes: a large single-center study.

    LENUS (Irish Health Repository)

    O'Hare, A M

    2010-11-01

    The HydroCoil is an expansile hydrogel coil designed to produce a greater degree of volumetric packing within cerebral aneurysms when compared with bare platinum coils. This increased packing is, in turn, believed to decrease the risk of recurrence within aneurysms and hence the risk of their rupture in the long term. The aim of this work was to assess whether the use of HydroCoils and the proportion of HydroCoil used have any influence on the subsequent occlusion and recurrence rates of treated aneurysms.

  14. Correlation of angina pectoris and perfusion decrease by collateral circulation in single-vessel coronary chronic total occlusion using myocardial perfusion single-photon emssion computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sang Geon; Park, Ki Seong; Kang, Sae Ryung [Chonnam National University Hospital, Gwangju (Korea, Republic of); and others

    2016-03-15

    To evaluate the perfusion decrease in donor myocardium by collateral circulation and its correlation with angina pectoris in patients with chronic total occlusion (CTO) using myocardial perfusion single-photon emission computed tomography (MPS). Thirty-six patients with single-vessel CTO without any other stenosis were included. All patients underwent MPS and coronary angiography (CAG) within 2 months. Total 72 donor arteries were evaluated for the grades of collaterals to the CTO artery using the Rentrop grading system on CAG. Perfusion defects and perfusion scores in donor and CTO territories were analyzed on MPS. Myocardial perfusion of donor and CTO territories were evaluated according to the presence of angina pectoris and the grades of collateral circulation. When the CTO territory was ischemic, symptomatic patients showed higher summed difference scores in the CTO territory compared to asymptomatic patients (3.5 ± 2.4 vs. 1.5 ± 0.8 for symptomatic and asymptomatic groups respectively; p = 0.034). However, when the CTO territory was nonischemic, symptomatic patients showed higher summed stress scores (SSS, 4.3 ± 2.9 vs. 1.6 ± 1.2; p = 0.032) and summed rest scores (SRS, 4.2 ± 2.5 vs. 1.5 ± 1.1; p = 0.003) in the donor territories. On the per-vessel analysis, perfusion defects in donor territories were more frequent (0 % vs. 53 % vs. 86 % for Rentrop 0, Rentrop 1–2 and Rentrop 3, respectively; p < 0.001) and showed higher SSS (0.0 ± 0.0, 1.3 ± 1.6 and 2.1 ± 1.1 for Rentrop 0, Rentrop 1–2 and Rentrop 3, respectively; p = 0.001) and SRS (0.0 ± 0.0, 1.0 ± 1.4 and 1.7 ± 1.2; p = 0.003) at higher Rentrop grades, but their patterns were variable. Angina pectoris was related to either ischemia of the myocardium beyond CTO or a perfusion decrease in the donor myocardium. The perfusion decrease in donor myocardium positively correlated with the collateral grades.

  15. Comparison of drug eluting stent implantation with coronary artery bypass surgery in the treatment of patients with chronic total occlusion and multiple vessel disease

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; ZHU Xiao-Ling; MA Chang-sheng; KANG Jun-ping; DU Xin; CHEN Fang; ZHOU Yu-jie; L(U) Shu-zheng; HUANG Fang-jiong; GU Cheng-xiong

    2011-01-01

    Background In patients with chronic total occlusion (CTO) and multivessel coronary artery disease, the comparison of surgical and the percutaneous revascularization strategies has rarely been conducted. The aim of this study was to compare long term clinical outcomes of drug eluting stent (DES) implantation with coronary artery bypass surgery (CABG)in the patients with CTO and multivessel disease.Methods From a prospective registry of 6000 patients in our institution, we included patients with CTO and multivessel coronary artery disease who underwent either CABG (n=679) or DES (n=267) treatment. Their propensity risk score was used for adjusting baseline differences.Results At a median follow-up of three years, propensity score adjusted Cox regression analysis showed that the rate of major adverse cardiac cerebrovascular events (MACCE) was lower in CABG group (12.7% vs. 24.3%, hazard ratio (HR) 1.969, 95% Cl 1.219-3.179, P=0.006) mainly due to lower rate of target vessel revascularization in CABG group than in DES group (3.1% vs. 17.2%, HR 16.14, 95% CI 5.739-45.391, P <0.001). The incidence of cardiac death or myocardial infarction (composite end point) was not significantly different between these two groups. On multivariate analysis, the significant predictors of MACCE were only the type of revascularization. Age, left ventricular ejection fraction (LVEF), and complete revascularization were identified as significant predictors of composite end points.Conclusions Our study shows that in patients with CTO and multivessel coronary disease, DES can offer comparable long term outcomes in cardiac death and myocardial infraction free survival in comparison with CABG. However, there is an increased rate of MACCE which results from more repeat revascularizations. Obtaining a complete revascularization is crucial for decreasing adverse cardiac events.

  16. Role of precoating in artificial vessel endothelialization

    Institute of Scientific and Technical Information of China (English)

    肖乐; 时德

    2004-01-01

    @@ As the progress of vascular surgery, artificial vessels have become the substitute for large and middle diameter vessels but have not for small diameter ones owing to thrombogenesis and occlusion within a short period of time after being applied.Artificial vessel endothelialization is one of the ideal methods to resolve such issue and has been improved continuously since Herring1 in 1978 put forward this term in the first time and utilized vascular endothelial cells (ECs) harvested from living animals to perform the test of artificial vessel endothelialization.

  17. Use of positron emission tomography (PET) for the diagnosis of large-vessel vasculitis.

    Science.gov (United States)

    Loricera, J; Blanco, R; Hernández, J L; Martínez-Rodríguez, I; Carril, J M; Lavado, C; Jiménez, M; González-Vela, C; González-Gay, M Á

    2015-01-01

    The term vasculitis encompasses a heterogeneous group of diseases that share the presence of inflammatory infiltrates in the vascular wall. The diagnosis of large-vessel vasculitis is often a challenge because the presenting clinical features are nonspecific in many cases and they are often shared by different types of autoimmune and inflammatory diseases including other systemic vasculitides. Moreover, the pathogenesis of large-vessel vasculitis is not fully understood. Nevertheless, the advent of new imaging techniques has constituted a major breakthrough to establish an early diagnosis and a promising tool to monitor the follow-up of patients with largevessel vasculitis. This is the case of the molecular imaging with the combination of positron emission tomography with computed tomography (PET/CT) using different radiotracers, especially the (18)F-fluordeoxyglucose ((18)F-FDG). In this review we have focused on the contribution of (18)F-FDG PET in the diagnosis of large-vessel vasculitis. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  18. Application of a modified regularization procedure for estimating oxygen tension in large retinal blood vessels

    Science.gov (United States)

    Yildirim, Isa; Ansari, Rashid; Samil Yetik, I.; Shahidi, Mahnaz

    2010-03-01

    Phosphorescence lifetime measurement based on a frequency domain approach is used to estimate oxygen tension in large retinal blood vessels. The classical least squares (LS) estimation was initially used to determine oxygen tension indirectly from intermediate variables. A spatial regularized least squares (RLS) method was later proposed to reduce the high variance of oxygen tension estimated by LS method. In this paper, we provide a solution using a modified RLS (MRLS) approach that utilizes prior knowledge about retinal vessels oxygenation based on expected oxygen tension values in retinal arteries and veins. The performance of MRLS method was evaluated in simulated and experimental data by determining the bias, variance, and mean absolute error (MAE) of oxygen tension measurements and comparing these parameters with those derived with the use of LS and RLS methods.

  19. Design and in-vitro evaluation of a tissue engineered large vessel prosthesis

    Science.gov (United States)

    Mahmood, Ayesha

    Tissue engineering of large diameter blood vessels can offer a promising long-term solution to the large population suffering from congenital vascular defects and other vascular disease. In this report design, assembly, in vitro maturation and evaluation of a large diameter, chitosan-based prosthesis is described. To facilitate cell adhesion and proliferation, collagen was included as a scaffold component to a chitosan scaffold. In vitro studies evaluated the role of collagen content, crosslinker type and crosslinking density on degradation kinetics, mechanical properties and cellular interactions. Finally, the vessel scaffold (ID = 12 mm, OD = 15 mm) was fabricated from a moderately cross-linked, 90%/10% chitosan/collagen material. A tubular scaffold with gradient porosity and interconnected pores was generated by controlled freezing and lyophilization of the polymer. For graft culture laminar and pulsatile flow systems were designed and porous scaffolds were seeded with vascular cells under static conditions. Laminar system grafts were seeded and cultured/analyzed over an 8 week period (15ml/min). For the pulsatile system SMC were seeded and after 2 weeks of pulsatile flow culture (360ml/min, 82 beats/min) microvascular EC were seeded lumenally to initiate a microvascular network followed by aortic EC seeding at 3 weeks. For both systems, cell viability at different culture periods showed the formation of high density of cell within few weeks of graft culture. However, the pulsatile flow system graft showed a significant increase in mechanical properties and ECM protein (collagen and elastin) deposition overtime. This novel chitosan based tissue engineered vascular graft shows promising results for large vessel replacements.

  20. Estimation of turbulence dissipation rate by Large eddy PIV method in an agitated vessel

    Directory of Open Access Journals (Sweden)

    Kysela Bohuš

    2015-01-01

    Full Text Available The distribution of turbulent kinetic energy dissipation rate is important for design of mixing apparatuses in chemical industry. Generally used experimental methods of velocity measurements for measurement in complex geometries of an agitated vessel disallow measurement in resolution of small scales close to turbulence dissipation ones. Therefore, Particle image velocity (PIV measurement method improved by large eddy Ply approach was used. Large eddy PIV method is based on modeling of smallest eddies by a sub grid scale (SGS model. This method is similar to numerical calculations using Large Eddy Simulation (LES and the same SGS models are used. In this work the basic Smagorinsky model was employed and compared with power law approximation. Time resolved PIV data were processed by Large Eddy PIV approach and the obtained results of turbulent kinetic dissipation rate were compared in selected points for several operating conditions (impeller speed, operating liquid viscosity.

  1. Nonlinear excitations of blood flow in large vessels under thermal radiations and uniform magnetic field

    Science.gov (United States)

    Tabi, C. B.; Motsumi, T. G.; Bansi Kamdem, C. D.; Mohamadou, A.

    2017-08-01

    A nonlinear model of blood flow in large vessels is addressed. The influence of radiations, viscosity and uniform magnetic fields on velocity and temperature distribution waveforms is studied. Exact solutions for the studied model are investigated through the F - expansion method. Based on the choice of parameter values, single-, multi-soliton and Jacobi elliptic function solutions are obtained. Viscosity and permanent magnetic field bring about wave spreading and reduce the velocity of blood, while radiations have reversed effects with strong impact on the waveform frequency of both the velocity and temperature distribution.

  2. 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.

  3. MELCOR 1.8.3 assessment: GE large vessel blowdown and level swell experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kmetyk, L.N.

    1994-07-01

    MELCOR is a fully integrated, engineering-level computer code, being developed at Sandia National Laboratories for the USNRC, that models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRS. As part of an ongoing assessment program, the MELCOR computer code has been used to analyze a series of blowdown tests performed in the early 1980s at General Electric. The GE large vessel blowdown and level swell experiments are a set of primary system thermal/hydraulic separate effects tests studying the level swell phenomenon for BWR transients and LOCAS; analysis of these GE tests is intended to validate the new implicit bubble separation algorithm added since the release of MELCOR 1.8.2. Basecase MELCOR results are compared to test data, and a number of sensitivity studies on input modelling parameters and options have been done. MELCOR results for these experiments also are compared to MAAP and TRAC-B qualification analyses for the same tests. Time-step and machine-dependency calculations were done to identify whether any numeric effects exist in our GE large vessel blowdown and level swell assessment analyses.

  4. The microcirculation: a motor for the systemic inflammatory response and large vessel disease induced by hypercholesterolaemia?

    Science.gov (United States)

    Stokes, Karen Y; Granger, D Neil

    2005-01-01

    There is abundant evidence that links hypercholesterolaemia to both vascular inflammation and atherogenesis. While atherosclerosis is a large vessel disease that is characterized by leucocyte infiltration and lipid deposition in the wall of lesion-prone arteries, the inflammatory response does not appear to be confined to these locations. There is evidence supporting a systemic inflammatory response that is characterized by endothelial cell activation in multiple vascular beds and the appearance of activated immune cells and a wide range of inflammatory mediators in blood. The mechanism(s) responsible for initiating this systemic response remain poorly defined, although several inciting factors have been proposed, including infectious agents and oxidative stress resulting from one or more of the cardiovascular risk factors (e.g. hypercholesterolaemia, hypertension). While cells within lesion-prone arteries are often inferred as the source of circulating inflammatory mediators during atherogenesis, the fact that endothelial cells throughout the vasculature are activated raises the possibility that the microvasculature (which encompasses a vast endothelial surface area) may contribute to creating the systemic inflammatory milieu that is linked to atherogenesis. This review addresses evidence that links the microvasculature to the inflammatory responses induced by hypercholesterolaemia and offers the hypothesis that inflammatory events initiated within the microcirculation may contribute to initiation and/or progression of large vessel disease. PMID:15611017

  5. Review of pressurized thermal shock studies of large scale reactor pressure vessels in Hungary

    Directory of Open Access Journals (Sweden)

    Tamás Fekete

    2016-03-01

    Full Text Available In Hungary, four nuclear power units were constructed more than 30 years ago; they are operating to this day. In every unit, VVER-440 V213-type light-water cooled, light-water moderated, ressurized water reactors are in operation. Since the mid-1980s, numerous researches in the field of Pressurized Thermal Shock (PTS analyses of Reactor Pressure Vessels (RPVs have been conducted in Hungary; in all of them, the concept of structural integrity was the basis of research and development. During this time, four large PTS studies with industrial relevance have been completed in Hungary. Each used different objectives and guides, and the analysis methodology was also changing. This paper gives a comparative review of the methodologies used in these large PTS Structural Integrity Analysis projects, presenting the latest results as well

  6. Transcatheter occlusion of a large coronary artery fistula using a patent ductus arteriosus occluder.

    Science.gov (United States)

    Białkowski, Jacek; Szkutnik, Małgorzata; Fiszer, Roland; Zembala, Marian

    2011-01-01

    A large fistula from the left coronary artery to the right ventricle was successfully closed percutaneously in a 40 year-old patient using a patent ductus arteriosus occluder. The device was positioned and deployed via the venous system using a guidewire that had been advanced via the aorta, coronary artery and fistula to the venous circulation (arterio-venous loop creation). No complications were reported at follow-up.

  7. Beam localization in HIFU temperature measurements using thermocouples, with application to cooling by large blood vessels.

    Science.gov (United States)

    Dasgupta, Subhashish; Banerjee, Rupak K; Hariharan, Prasanna; Myers, Matthew R

    2011-02-01

    Experimental studies of thermal effects in high-intensity focused ultrasound (HIFU) procedures are often performed with the aid of fine wire thermocouples positioned within tissue phantoms. Thermocouple measurements are subject to several types of error which must be accounted for before reliable inferences can be made on the basis of the measurements. Thermocouple artifact due to viscous heating is one source of error. A second is the uncertainty regarding the position of the beam relative to the target location or the thermocouple junction, due to the error in positioning the beam at the junction. This paper presents a method for determining the location of the beam relative to a fixed pair of thermocouples. The localization technique reduces the uncertainty introduced by positioning errors associated with very narrow HIFU beams. The technique is presented in the context of an investigation into the effect of blood flow through large vessels on the efficacy of HIFU procedures targeted near the vessel. Application of the beam localization method allowed conclusions regarding the effects of blood flow to be drawn from previously inconclusive (because of localization uncertainties) data. Comparison of the position-adjusted transient temperature profiles for flow rates of 0 and 400ml/min showed that blood flow can reduce temperature elevations by more than 10%, when the HIFU focus is within a 2mm distance from the vessel wall. At acoustic power levels of 17.3 and 24.8W there is a 20- to 70-fold decrease in thermal dose due to the convective cooling effect of blood flow, implying a shrinkage in lesion size. The beam-localization technique also revealed the level of thermocouple artifact as a function of sonication time, providing investigators with an indication of the quality of thermocouple data for a given exposure time. The maximum artifact was found to be double the measured temperature rise, during initial few seconds of sonication.

  8. Intra-arterial thrombolysis using rt-PA in patients with acute stroke due to vessel occlusion of anterior and/or posterior cerebral circulation

    Energy Technology Data Exchange (ETDEWEB)

    Tountopoulou, Argyro; Ahl, Bjoern; Weissenborn, Karin [Hannover Medical School, Department of Neurology and Clinical Neurophysiology, Hannover (Germany); Becker, Hartmut; Goetz, Friedrich [Hannover Medical School, Department of Neuroradiology, Hannover (Germany)

    2008-01-15

    The aim of our study was to evaluate the safety and efficacy of intra-arterial (IA) thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute stroke due to occlusion in the anterior or posterior circulation. We retrospectively analyzed the clinical and radiological data of 88 consecutive patients with acute ischemic stroke who underwent emergency cerebral angiography for the purpose of subsequent IA thrombolysis. The neurological deficit on admission and discharge was graded using the National Institutes of Health Stroke Scale (NIHSS) score. Baseline computer tomography (CT) scans were examined for any signs indicative of cerebral ischemia. The angiographic findings were classified according to the Thrombolysis in Myocardial Infarction (TIMI) score for myocardial infarction. Follow-up CT scans were examined for hemorrhagic complication. Of the 88 patients who underwent IA thrombolysis, 63 presented with complete or partial arterial occlusion in the suspected perfusion area. In these 63 patients, the median NIHSS score dropped from 15 points on admission to 10 points at discharge. The recanalization rate was 52.6% for partial and complete reperfusion. In-hospital mortality was 20.6% (9.1% for carotid, 44.4% for basilar territory occlusion). Intracerebral bleeding (ICB) occurred in 38.6% of the patients with occlusion in the anterior circulation, resulting in these patients presenting a worse clinical outcome than those without ICB. Only minor extracranial bleedings occurred in 20.6% of patients. Patients with ICB had a significantly higher frequency of ischemic signs on the baseline CT scan. Occlusion of a cerebral artery is present in about 75% of the patients eligible for thrombolytic therapy. Intra-arterial thrombolysis using rt-PA in patients with acute ischemic stroke can achieve re-vascularization, although ICB remains the major risk factor affecting its efficacy. (orig.)

  9. Intravenous thrombolysis before endovascular therapy for large vessel strokes can lead to significantly higher hospital costs without improving outcomes.

    Science.gov (United States)

    Rai, Ansaar T; Boo, SoHyun; Buseman, Chelsea; Adcock, Amelia K; Tarabishy, Abdul R; Miller, Maurice M; Roberts, Thomas D; Domico, Jennifer R; Carpenter, Jeffrey S

    2017-01-06

    Limited efficacy of IV recombinant tissue plasminogen activator (rt-PA) for large vessel occlusions (LVO) raises doubts about its utility prior to endovascular therapy. To compare outcomes and hospital costs for anterior circulation LVOs (middle cerebral artery, internal carotid artery terminus (ICA-T)) treated with either primary endovascular therapy alone (EV-Only) or bridging therapy (IV+EV)). A single-center retrospective analysis was performed. Clinical and demographic data were collected prospectively and relevant cost data were obtained for each patient in the study. 90 consecutive patients were divided into EV-Only (n=52) and IV+EV (n=38) groups. There was no difference in demographics, stroke severity, or clot distribution. The mean (SD) time to presentation was 5:19 (4:30) hours in the EV-Only group and 1:46 (0:52) hours in the IV+EV group (pIV+EV 31 (81.6%) (p=0.12). Favorable outcome: EV-Only 26 (50%) versus IV+EV 22 (58%) (p=0.45). For patients presenting within 4.5 hours (n=64): Recanalization: EV-Only 21/26 (81%) versus IV+EV 31/38 (81.6%) (p=0.93). Favorable outcome: EV-Only 14/26 (54%) versus IV+EV 22/38 (58%) (p=0.75). There was no significant difference in rates of hemorrhage, mortality, home discharge, or length of stay. A stent retriever was used in 67 cases (74.4%), with similar recanalization, outcomes, and number of passes in the EV-Only and IV+EV groups. The mean (SD) total hospital cost was $33 810 (13 505) for the EV-Only group and $40 743 (17 177) for the IV+EV group (p=0.02). The direct cost was $23 034 (8786) for the EV-Only group and $28 711 (11 406) for the IV+EV group (p=0.007). These significantly higher costs persisted for the subgroup presenting in IV rt-PA administration independently predicted higher hospital costs. IV rt-PA did not improve recanalization, thrombectomy efficacy, functional outcomes, or length of stay. Combined therapy was associated with significantly higher total and direct hospital costs

  10. Numerical modeling of in-vessel melt water interaction in large scale PWR`s

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, N.I. [Siemens AG, KWU NA-M, Erlangen (Germany)

    1998-01-01

    This paper presents a comparison between IVA4 simulations and FARO L14, L20 experiments. Both experiments were performed with the same geometry but under different initial pressures, 51 and 20 bar respectively. A pretest prediction for test L21 which is intended to be performed under an initial pressure of 5 bar is also presented. The strong effect of the volume expansion of the evaporating water at low pressure is demonstrated. An in-vessel simulation for a 1500 MW el. PWR is presented. The insight gained from this study is: that at no time are conditions for the feared large scale melt-water intermixing at low pressure in force, with this due to the limiting effect of the expansion process which accelerates the melt and the water into all available flow paths. (author)

  11. Effect of variable heat transfer coefficient on tissue temperature next to a large vessel during radiofrequency tumor ablation

    Directory of Open Access Journals (Sweden)

    Pinheiro Cleber

    2008-07-01

    Full Text Available Abstract Background One of the current shortcomings of radiofrequency (RF tumor ablation is its limited performance in regions close to large blood vessels, resulting in high recurrence rates at these locations. Computer models have been used to determine tissue temperatures during tumor ablation procedures. To simulate large vessels, either constant wall temperature or constant convective heat transfer coefficient (h have been assumed at the vessel surface to simulate convection. However, the actual distribution of the temperature on the vessel wall is non-uniform and time-varying, and this feature makes the convective coefficient variable. Methods This paper presents a realistic time-varying model in which h is a function of the temperature distribution at the vessel wall. The finite-element method (FEM was employed in order to model RF hepatic ablation. Two geometrical configurations were investigated. The RF electrode was placed at distances of 1 and 5 mm from a large vessel (10 mm diameter. Results When the ablation procedure takes longer than 1–2 min, the attained coagulation zone obtained with both time-varying h and constant h does not differ significantly. However, for short duration ablation (5–10 s and when the electrode is 1 mm away from the vessel, the use of constant h can lead to errors as high as 20% in the estimation of the coagulation zone. Conclusion For tumor ablation procedures typically lasting at least 5 min, this study shows that modeling the heat sink effect of large vessels by applying constant h as a boundary condition will yield precise results while reducing computational complexity. However, for other thermal therapies with shorter treatment using a time-varying h may be necessary.

  12. Factor V Leiden Is Associated with Higher Risk of Deep Venous Thrombosis of Large Blood Vessels

    Science.gov (United States)

    Arsov, Todor; Miladinova, Daniela; Spiroski, Mirko

    2006-01-01

    Aim To determine the prevalence of factor V Leiden mutation in patients with different presentation of venous thromboembolic disease and healthy individuals in the Republic of Macedonia. Methods The retrospective case-control study involved 190 patients with venous thromboembolic disease and 200 healthy individuals, who were screened for the presence of factor V Leiden mutation, using a polymerase chain reaction-restriction fragment length polymorphism method. The prevalence of factor V Leiden was analyzed according to the localization of thrombosis, presence of risk factors, and family history of thrombosis. The odds of deep venous thrombosis were calculated with respect to the presence of factor V Leiden mutation. Results The prevalence of factor V Leiden mutation among patients with venous thromboembolic disease was 21.1%, compared with 5.5% in the healthy individuals. Factor V Leiden positive patients had the first episode of deep venous thrombosis at a younger age, and the prevalence of the mutation was the highest among patients with a positive family history of thrombosis (33.9%, P = 0.003) and in patients with deep venous thrombosis affecting a large blood vessel (37.7%, P = 0.001). The prevalence of factor V Leiden mutation was lower in patients with calf deep venous thrombosis and primary thromboembolism (13.3% and 13.1%, respectively; P>0.05). The odds ratio for iliofemoral or femoral deep venous thrombosis in factor V Leiden carriers was 10.4 (95% confidence interval, 4.7-23.1). Conclusion The prevalence of factor V Leiden mutation was high in patients with venous thromboembolic disease and healthy individuals in the Republic of Macedonia. Factor V Leiden carriers have the highest odds of developing deep venous thrombosis affecting a large venous blood vessel. PMID:16758522

  13. Stent-based mechanical thrombectomy in acute basilar artery occlusion.

    Science.gov (United States)

    Cohen, José E; Leker, Ronen R; Moscovici, Samuel; Attia, Moshe; Itshayek, Eyal

    2011-12-01

    Stent-based mechanical thrombectomy was recently proposed as an effective alternative to other mechanical techniques to achieve recanalization of large-vessel embolic occlusions in the anterior circulation. To our knowledge, there are no reports of the use of this technique in acute basilar artery occlusion (ABAO). We present a patient with complete endovascular recanalization of ABAO using a stent-based thrombectomy technique. Advantages and limitations of this technique in the management of ABAO are discussed. The stent-thrombectomy technique is promising, and will need further evaluation in posterior circulation stroke. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Imaging large vessel vasculitis with fully integrated PET/MRI: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Einspieler, Ingo; Pyka, Thomas; Eiber, Matthias [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Nuclear Medicine, Munich (Germany); Thuermel, Klaus; Wolfram, Sabine; Moog, Philipp [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Nephrology, Munich (Germany); Reeps, Christian [Technische Universitaet Muenchen, Department of Vascular Surgery, Klinikum rechts der Isar, Munich (Germany); Essler, Markus [Rheinische Friedrich-Wilhelms-Universitaet, Department of Nuclear Medicine, Universitaetsklinikum Bonn, Bonn (Germany)

    2015-04-16

    The aim of this study was to evaluate the feasibility of hybrid [{sup 18}F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI in patients with large vessel vasculitis (LVV) by comparing visual and quantitative parameters to that of PET/CT. Furthermore, the value of PET/MRI in disease activity and extent of LVV was assessed. A total of 16 [{sup 18}F]FDG PET/MRI and 12 [{sup 18}F]-FDG PET/CT examinations were performed in 12 patients with LVV. MRI of the vessel wall by T1-weighted and T2-weighted sequences was used for anatomical localization of FDG uptake and identification of morphological changes associated with LVV. In addition, contrast-enhanced (CE) magnetic resonance angiography (MRA) was performed. The vascular FDG uptake in the vasculitis group was compared to a reference group of 16 patients using a four-point visual score. Visual scores and quantitative parameters [maximum standardized uptake value (SUV{sub max}) and target to background ratio (TBR)] were compared between PET/MRI and PET/CT. Furthermore, correlations between C-reactive protein (CRP) and quantitative PET results, as well the extent of vasculitis in PET, MRI/CE-MRA and combined PET/MRI, were analysed. TBRs, SUV{sub max} values and visual scores correlated well between PET/MRI and PET/CT (r = 0.92, r = 0.91; r = 0.84, p < 0.05). There was no significant difference between both modalities concerning SUV{sub max} measurements and visual scores. In PET/MRI, PET alone revealed abnormal FDG uptake in 86 vascular regions. MRI/CE-MRA indicated 49 vessel segments with morphological changes related to vasculitis, leading to a total number of 95 vasculitis regions in combination with PET. Strong and significant correlations between CRP and disease extent in PET alone (r = 0.75, p = 0.0067) and PET/MRI (r = 0.92, p < 0.0001) in contrast to MRI/CE-MRA only were observed. Regarding disease activity, no significant correlations were seen between quantitative PET results and CRP, although there

  15. Electrospun vascular scaffold for cellularized small diameter blood vessels: A preclinical large animal study.

    Science.gov (United States)

    Ju, Young Min; Ahn, Hyunhee; Arenas-Herrera, Juan; Kim, Cheil; Abolbashari, Mehran; Atala, Anthony; Yoo, James J; Lee, Sang Jin

    2017-09-01

    The strategy of vascular tissue engineering is to create a vascular substitute by combining autologous vascular cells with a tubular-shaped biodegradable scaffold. We have previously developed a novel electrospun bilayered vascular scaffold that provides proper biological and biomechanical properties as well as structural configuration. In this study, we investigated the clinical feasibility of a cellularized vascular scaffold in a preclinical large animal model. We fabricated the cellularized vascular construct with autologous endothelial progenitor cell (EPC)-derived endothelial cells (ECs) and smooth muscle cells (SMCs) followed by a pulsatile bioreactor preconditioning. This fully cellularized vascular construct was tested in a sheep carotid arterial interposition model. After preconditioning, confluent and mature EC and SMC layers in the scaffold were achieved. The cellularized constructs sustained the structural integrity with a high degree of graft patency without eliciting an inflammatory response over the course of the 6-month period in sheep. Moreover, the matured EC coverage on the lumen and a thick smooth muscle layer were formed at 6months after transplantation. We demonstrated that electrospun bilayered vascular scaffolds in conjunction with autologous vascular cells may be a clinically applicable alternative to traditional prosthetic vascular graft substitutes. This study demonstrates the utility of tissue engineering to provide platform technologies for rehabilitation of patients recovering from severe, devastating cardiovascular diseases. The long-term goal is to provide alternatives to vascular grafting using bioengineered blood vessels derived from an autologous cell source with a functionalized vascular scaffold. This novel bilayered vascular construct for engineering blood vessels is designed to offer "off-the-shelf" availability for clinical translation. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. A Review of Large-Scale Fracture Experiments Relevant to Pressure Vessel Integrity Under Pressurized Thermal Shock Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, C.E.

    2001-01-29

    Numerous large-scale fracture experiments have been performed over the past thirty years to advance fracture mechanics methodologies applicable to thick-wall pressure vessels. This report first identifies major factors important to nuclear reactor pressure vessel (RPV) integrity under pressurized thermal shock (PTS) conditions. It then covers 20 key experiments that have contributed to identifying fracture behavior of RPVs and to validating applicable assessment methodologies. The experiments are categorized according to four types of specimens: (1) cylindrical specimens, (2) pressurized vessels, (3) large plate specimens, and (4) thick beam specimens. These experiments were performed in laboratories in six different countries. This report serves as a summary of those experiments, and provides a guide to references for detailed information.

  17. Retinal arterial occlusion in Takayasu′s arteritis

    Directory of Open Access Journals (Sweden)

    Kaushik Sushmita

    2005-01-01

    Full Text Available Takayasu′s arteritis is an auto-immune disorder of the large and medium-sized arteries, commonly involving the heart and its main vessels. It is now recognised that the inflammatory process of the large arteries affects regions of the walls supplied by the vasa vasorum, suggesting that primary small vessel involvement may contribute to the development of the clinico-pathological features of Takayasu aorto-arteritis. Classical ophthalmic features of the disease result from reduced ocular perfusion, which manifests as hypoxic retinal changes such as microaneurysms, arterio-venous anastomosis and non-perfused areas. Branch retinal artery occlusion has not been previously described in this condition. This case illustrates retinal arterial occlusion as the presenting feature of Takayasu′s arteritis.

  18. Tocilizumab in glucocorticoid-naïve large-vessel vasculitis.

    Science.gov (United States)

    Pazzola, G; Padovano, I; Boiardi, L; Versari, A; Pipitone, N; Catanoso, M; Pulsatelli, L; Meliconi, R; Salvarani, C

    2013-01-01

    Glucocorticoids (GC) are the mainstay of treatment of large-vessel vasculitis (LVV), but a sizeable number of patients relapse upon tapering the GC dose or after discontinuation of GC therapy. In addition, GC cause numerous adverse events. Therefore, in patients with longstanding disease and in those at risk for GC-related adverse events, the use of alternative therapeutic agents should be considered. Interleukin-6 (IL-6) is a key player in the pathogenesis of LVV. Preliminary data suggest the efficacy of the IL-6 receptor inhibitor tocilizumab (TCZ) in patients with LVV. We report 2 treatment-naïve patients with a recent diagnosis of LVV who received monthly TCZ infusions (8 mg/kg body weight) for 6 consecutive months as monotherapy because of relative contraindications and patients' reluctance to take GC. In both cases we observed a complete clinical response and normalisation of inflammatory markers as well as a decrease in vascular FDG uptake and SUV ratio on fluorodeoxyglucose positron emission/computerised tomography. Serum IL-6 and soluble IL-6 receptor (sIL-6R) levels rose in both patients after TCZ therapy. TCZ may be an effective alternative to GC treatment for LVV patients at risk for GC-related adverse events. Larger studies are required to confirm our findings.

  19. Imaging large vessel vasculitis with fully integrated PET/MRI: a pilot study.

    Science.gov (United States)

    Einspieler, Ingo; Thürmel, Klaus; Pyka, Thomas; Eiber, Matthias; Wolfram, Sabine; Moog, Philipp; Reeps, Christian; Essler, Markus

    2015-06-01

    The aim of this study was to evaluate the feasibility of hybrid [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI in patients with large vessel vasculitis (LVV) by comparing visual and quantitative parameters to that of PET/CT. Furthermore, the value of PET/MRI in disease activity and extent of LVV was assessed. A total of 16 [(18)F]FDG PET/MRI and 12 [(18)F]-FDG PET/CT examinations were performed in 12 patients with LVV. MRI of the vessel wall by T1-weighted and T2-weighted sequences was used for anatomical localization of FDG uptake and identification of morphological changes associated with LVV. In addition, contrast-enhanced (CE) magnetic resonance angiography (MRA) was performed. The vascular FDG uptake in the vasculitis group was compared to a reference group of 16 patients using a four-point visual score. Visual scores and quantitative parameters [maximum standardized uptake value (SUVmax) and target to background ratio (TBR)] were compared between PET/MRI and PET/CT. Furthermore, correlations between C-reactive protein (CRP) and quantitative PET results, as well the extent of vasculitis in PET, MRI/CE-MRA and combined PET/MRI, were analysed. TBRs, SUVmax values and visual scores correlated well between PET/MRI and PET/CT (r = 0.92, r = 0.91; r = 0.84, p vasculitis, leading to a total number of 95 vasculitis regions in combination with PET. Strong and significant correlations between CRP and disease extent in PET alone (r = 0.75, p = 0.0067) and PET/MRI (r = 0.92, p < 0.0001) in contrast to MRI/CE-MRA only were observed. Regarding disease activity, no significant correlations were seen between quantitative PET results and CRP, although there was a trend towards significance (r = 0.55, p = 0.0651). PET/MRI also showed active LVV in 15/16 examinations. Hybrid PET/MRI is feasible in LVV and holds promise for precisely determining disease extent and disease activity.

  20. Parameters related to a positive test result for FDG PET(/CT) for large vessel vasculitis : a multicenter retrospective study

    NARCIS (Netherlands)

    Hooisma, G. A.; Balink, H.; Houtman, P. M.; Slart, R. H. J. A.; Lensen, K. D. F.

    2012-01-01

    The purpose of this study was to identify clinical and laboratory parameters that may improve the effectiveness of the use of fluorodeoxyglucose positron emission tomography ((18) F-FDG PET)(/CT) for diagnosing large vessel vasculitis (LVV), and secondarily to assess the contribution of (18) F-FDG P

  1. Vascular plug for ICA occlusion in cavernous carotid aneurysms: technical note

    Energy Technology Data Exchange (ETDEWEB)

    Scott, David A.; Keston, Peter; White, Philip; Sellar, Robin [Western General Hospital, Division of Clinical Neurosciences, Edinburgh (United Kingdom)

    2008-09-15

    Large, symptomatic aneurysms of the cavernous internal carotid artery (ICA) can be successfully treated by a combination of aneurysm coiling and occlusion of the parent vessel. We describe the use of an Amplatzer (AGA medical corporation, Plymouth, MA, USA) detachable nitinol vascular plug to occlude the ICA in four patients with symptomatic cavernous ICA aneurysms. (orig.)

  2. Evaluation of creep-fatigue crack growth for large-scale FBR reactor vessel and NDE assessment

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Kim, Jong Bum; Kim, Seok Hun; Yoo, Bong

    2001-03-01

    Creep fatigue crack growth contributes to the failure of FRB reactor vessels in high temperature condition. In the design stage of reactor vessel, crack growth evaluation is very important to ensure the structural safety and setup the in-service inspection strategy. In this study, creep-fatigue crack growth evaluation has been performed for the semi-elliptical surface cracks subjected to thermal loading. The thermal stress analysis of a large-scale FBR reactor vessel has been carried out for the load conditions. The distributions of axial, radial, hoop, and Von Mises stresses were obtained for the loading conditions. At the maximum point of the axial and hoop stress, the longitudinal and circumferential surface cracks (i.e. PTS crack, NDE short crack and shallow long crack) were postulated. Using the maximum and minimum values of stresses, the creep-fatigue crack growth of the proposed cracks was simulated. The crack growth rate of circumferential cracks becomes greater than that of longitudinal cracks. The total crack growth of the largest PTS crack is very small after 427 cycles. The structural integrity of a large-scale reactor can be maintained for the plant life. The crack depth growth of the shallow long crack is faster than that of the NDE short crack. In the ISI of the large-scale FBR reactor vessel, the ultrasonic inspection is beneficial to detect the shallow circumferential cracks.

  3. Citrus sinensis leaf petiole and blade colonization by Xylella fastidiosa: details of xylem vessel occlusion Colonização de pecíolo e folha de Citrus sinensis por Xylella fastidiosa

    Directory of Open Access Journals (Sweden)

    Eduardo Alves

    2009-04-01

    Full Text Available Citrus variegated chlorosis (CVC, caused by Xylella fastidiosa, is an important disease of citrus in Brazil. X. fastidiosa is restricted to xylem vessels of plants and knowledge regarding xylem colonization is still limited. Our goal was to verify how this bacterium colonizes and spreads within xylem vessels of sweet orange Citrus sinensis cv. Pêra. Petioles and pieces of leaf blades from naturally infected plant exhibiting characteristic symptoms were prepared for light microscopy (LM, scanning electron microscopy (SEM, transmission electron microscopy (TEM and immunogold labeling (IGL. Petioles from healthy plants were used as control. IGL results, using an antibody against wall hemicelluloses, revealed that the pit membrane of vessels was altered. Bacterial cells were observed in the pit between adjacent vessels. Results support the contention that X. fastidiosa produces cellulases to reach adjacent vessels. SEM revealed that colonization of sweet orange started with X. fastidiosa cells attaching to the xylem wall, followed by an increase in the number of bacterial cells, the production of fibrous material, and finally vessel occlusion by biofilm composed of copious amounts of amorphous material, strands and cells. Phenolic materials, hyperplasia and hypertrophy were noticed in leaves with gummy material. Xylem vessels frequently contained an unknown needle-like, crystallized matter blocking the vessel.A clorose variegada dos citrus (CVC, causada por uma bactéria restrita ao xilema (Xylella fastidiosa, é uma importante doença de citros no Brasil, entretanto, pouco se sabe sobre a colonização dos vasos do xilema pela bactéria. O objetivo deste trabalho foi estudar como X. fastidiosa invade os vasos adjacentes do xilema e algumas das alterações expressas por plantas de laranja Pêra. Foram coletadas 15 amostras de pecíolos e áreas das folhas de plantas com sintomas característicos da doença, as quais foram preparadas para

  4. Imaging of large vessel vasculitis with {sup 18}FDG PET: illusion or reality? A critical review of the literature data

    Energy Technology Data Exchange (ETDEWEB)

    Belhocine, Tarik; Vandevivere, Johan [Department of Nuclear Medicine, A.Z. Middelheim Hospital, 2020, Antwerp (Belgium); Blockmans, Daniel [Department of Internal Medicine, Gasthuisberg University Hospital, Leuven (Belgium); Hustinx, Roland [Department of Nuclear Medicine, University Hospital of Liege, Liege (Belgium); Mortelmans, Luc [Department of Nuclear Medicine, Gasthuisberg University Hospital, Leuven (Belgium)

    2003-09-01

    Fluorine-18 fluorodeoxyglucose positron emission tomography ({sup 18}FDG PET) plays a major role in the management of oncology patients. Owing to the singular properties of the glucose tracer, many patients suffering from non-malignant diseases such as inflammatory or infectious diseases may also derive clinical benefit from the appropriate use of metabolic imaging. Large vessel vasculitides such as giant cell arteritis and Takayasu arteritis are other examples that may potentially extend the field of {sup 18}FDG PET indications. The purpose of the present article is to assess the feasibility of metabolic imaging in vasculitis on the basis of the current literature data. In particular, the clinical context and the {sup 18}FDG imaging patterns seen in patients with large vessel vasculitis are analysed in order to identify potential indications for metabolic imaging. (orig.)

  5. Robust and enduring atorvastatin-mediated memory recovery following the 4-vessel occlusion/internal carotid artery model of chronic cerebral hypoperfusion in middle-aged rats.

    Science.gov (United States)

    Zaghi, Gislene Gonçalves Dias; Godinho, Jacqueline; Ferreira, Emilene Dias Fiuza; Ribeiro, Matheus Henrique Dal Molin; Previdelli, Isolde Santos; de Oliveira, Rúbia Maria Weffort; Milani, Humberto

    2016-02-01

    Chronic cerebral hypoperfusion (CCH) is a common condition associated with the development and/or worsening of age-related dementia.We previously reported persistent memory loss and neurodegeneration after CCH in middle-aged rats. Statin-mediated neuroprotection has been reported after acute cerebral ischemia. Unknown, however, is whether statins can alleviate the outcome of CCH. The present study investigated whether atorvastatin attenuates the cognitive and neurohistological outcome of CCH. Rats (12–15 months old) were trained in a non-food-rewarded radial maze, and then subjected to CCH. Atorvastatin (10 mg/kg, p.o.) was administered for 42 days or 15 days, beginning 5 h after the first occlusion stage. Retrograde memory performance was assessed at 7, 14, 21, 28, and 35 days of CCH, and expressed by “latency,” “number of reference memory errors” and “number of working memory errors.” Neurodegeneration was then examined at the hippocampus and cerebral cortex. Compared to sham, CCH caused profound and persistent memory loss in the vehicle-treated groups, as indicated by increased latency (91.2% to 107.3%) and number of errors (123.5% to 2508.2%), effects from which the animals did not spontaneously recover across time. This CCH-induced retrograde amnesia was completely prevented by atorvastatin (latency: −4.3% to 3.3%; reference/working errors: −2.5% to 45.7%), regardless of the treatment duration. This effect was sustained during the entire behavioral testing period (5 weeks), even after discontinuing treatment. This robust and sustained memory-protective effect of atorvastatin occurred in the absence of neuronal rescue (39.58% to 56.45% cell loss). We suggest that atorvastatin may be promising for the treatment of cognitive sequelae associated with CCH.

  6. Repetitive (18)F-FDG-PET/CT in patients with large-vessel giant-cell arteritis and controlled disease.

    Science.gov (United States)

    de Boysson, Hubert; Aide, Nicolas; Liozon, Eric; Lambert, Marc; Parienti, Jean-Jacques; Monteil, Jacques; Huglo, Damien; Bienvenu, Boris; Manrique, Alain; Aouba, Achille

    2017-08-30

    (18)F-FDG PET/CT can detect large-vessel involvement in giant-cell arteritis (GCA) with a good sensitivity. In patients with clinically and biologically controlled disease, we aimed to assess how vascular uptakes evolve on repetitive FDG-PET/CT. All included patients had to satisfy the 4 following criteria: 1) diagnosis of GCA was retained according to the criteria of the American College of Rheumatology or based on the satisfaction of 2 criteria associated with the demonstration of large-vessel involvement on FDG-PET/CT; 2) all patients had a positive PET/CT that was performed at diagnosis before treatment or within the first 10days of treatment; 3) another FDG-PET/CT was performed after at least 3months of controlled disease without any relapse; 4) patients were followed-up at least for 12months. Twenty-five patients (17 [68%] women, median age: 69 [65-78]) with large-vessel inflammation on a baseline FDG-PET/CT and with repetitive imaging during the period with controlled disease were included and followed-up for 62 [25-95] months. Four repeated procedures revealed total extinction of vascular uptakes at 11.5 [8-12] months after the first FDG-PET/CT. Eight PET/CT revealed decreased numbers of vascular uptakes, and 10 procedures revealed no changes. The 3 remaining procedures indicated worsening of the numbers of vascular uptakes in the absence of relapse. Our study revealed long-term persistent vascular uptake on repeated FDG-PET/CT in >80% of our GCA patients with large-vessel inflammation and clinical-biological controlled disease. Prospective studies are required to confirm these findings. Copyright © 2017 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  7. [New aspects of MRI for diagnostics of large vessel vasculitis and primary angiitis of the central nervous system].

    Science.gov (United States)

    Saam, T; Habs, M; Cyran, C C; Grimm, J; Pfefferkorn, T; Schüller, U; Reiser, M F; Nikolaou, K

    2010-10-01

    Vasculitis is a rare disease and clinical symptoms are often unspecific. Accurate and early diagnosis is mandatory in order to prevent complications, such as loss of vision or stroke. Imaging techniques can contribute to establishing a definite diagnosis and to evaluate disease activity and the extent of the disease in various vascular regions. Conventional imaging methods, such as computed tomography (CT) and magnetic resonance (MR) angiography, as well as digital subtraction angiography allow the vessel lumen but not the vessel wall to be depicted. However, vasculitis is a disease which primarily affects the vessel wall, therefore conventional imaging modalities often fail to make a definite diagnosis. Recently black-blood high resolution MR in vivo imaging has been used to visualize cervical and intracranial vasculitis. This review article presents imaging protocols for intracranial and cervical black-blood MR imaging and clinical cases with large vessel vasculitis and vasculitis of the central nervous system. Furthermore the current literature, examples of the most common differential diagnoses of cervical and cranial arteriopathy and the potential of other imaging modalities, such as PET/CT and ultrasound will be discussed.

  8. Numerical study on interaction of local air cooler with stratified hydrogen cloud in a large vessel

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Z. [Atomic Energy of Canada Limited, Chalk River Laboratories, ON K0J 1J0 (Canada); Andreani, M. [Laboratory for Thermal-Hydraulics, Paul Scherrer Institut, 5232 Villigen (Switzerland)

    2012-07-01

    Within the framework of the ERCOSAM project, planning calculations are performed to examine sensitivity parameters that can affect the break-up (erosion) of a helium layer by mitigation devices (i.e., cooler, spray, or Passive Autocatalytic Recombiner - PAR). This paper reports the GOTHIC analysis results for the cooler tests to be performed in the PANDA facility. The cooler elevation and geometry, helium layer thickness, steam distribution in the vessel, and the vessel geometry (inter-connected multi-compartments versus a single volume) on the erosion process as well as the cooling capacity are studied. This analysis is valuable because only a limited number of conditions will be examined in the planned experiments. The study provides a useful understanding of the interaction of a cooler with a stratified atmosphere. (authors)

  9. Large Vessel Vasculitis Occurring in Rheumatoid Arthritis Patient under Anti-TNF Therapy

    Directory of Open Access Journals (Sweden)

    Valentina Cestelli

    2014-01-01

    Full Text Available Vasculitis is a heterogeneous group of disorders characterized by the presence of necrotic inflammatory phenomena and destruction of blood vessels. Vasculitis is classified as primary (idiopathic or secondary to infections, connective tissue diseases and drugs but can also be considered as a paraneoplastic phenomenon. Evidence shows that the increasing use of biological agents results in a growing number of reports of autoimmune diseases induced by these therapies. An inflammatory articular chronic disease such as rheumatoid arthritis may be complicated by extra-articular manifestations, such as cutaneous or systemic vasculitis. Herewith, we describe the case of a great vessels arteritis in a patient affected by rheumatoid arthritis in therapy with an anti-TNF agent (etanercept.

  10. Fast Generation of Near-Optimal Plans for Eco-Efficient Stowage of Large Container Vessels

    DEFF Research Database (Denmark)

    Pacino, Dario; Delgado, Alberto; Jensen, Rune Møller

    2011-01-01

    Eco-efficient stowage plans that are both competitive and sustainable have become a priority for the shipping industry. Stowage planning is NP-hard and is a challenging optimization problem in practice. We propose a new 2-phase approach that generates near-optimal stowage plans and fulfills indus...... industrial time and quality requirements. Our approach combines an integer programming model for assigning groups of containers to storage areas of the vessel over multiple ports, and a constraint programming and local search procedure for stowing individual containers....

  11. Fast Generation of Near-Optimal Plans for Eco-Efficient Stowage of Large Container Vessels

    DEFF Research Database (Denmark)

    Pacino, Dario; Jensen, Rune Møller; Delgado-Ortegon, Alberto

    2011-01-01

    Eco-Efficient stowage plans that are both competitive and sustainable have become a priority for the shipping industry. Stowage planning is NP-hard and is a challenging optimization problem in practice. We propose a new 2-phase approach that generates near-optimal stowage plans and fulfills indus...... industrial time and quality requirements. Our approach combines an integer programming model for assigning groups of containers to storage areas of the vessel over multiple ports, and a constraint programming and local search procedure for stowing individual containers....

  12. Neuropeptide degradation by large vessel and microvessel-derived endothelial cells in vitro: cell surface catabolism of thyrotropin releasing hormone (TRH).

    Science.gov (United States)

    Rozental, J M; Kaminska, G; Turner, J; Schwartz, T; Cadahia, V; Brooks, B R

    1989-10-16

    Cell surface ectopeptidase activity of purified, cultured large vessel and microvessel-derived endothelial cells (EC) was studied. Degradation of thyrotropin releasing hormone (TRH), and production of cyclo-His-Pro was significantly increased (P less than 0.001) in large vessel EC compared with microcapillary EC. Since the rate of catabolism in the microvascular capillary bed is 5 times less than that in the large vessel wall, peptide concentrations are likely maintained longer in close proximity to their site of biosynthesis, where they are presumably most active.

  13. Mathematical Models and Numerical Simulations for the Blood Flow in Large Vessels

    Directory of Open Access Journals (Sweden)

    Titus PETRILA

    2012-12-01

    Full Text Available We are proposing a non-Newtonian, Cross type rheological model for the blood flow, under the conditions of an unsteady flow regime connected with the rhythmic pumping of the blood by the heart. We admit the incompressibility and homogeneity of the blood while its flow is laminar and the exterior body forces are neglected. We take also into account the viscoelastic behavior of the vessel walls. The mathematical equations and the appropriate boundary conditions are considered in cylindrical (axisymmetric coordinates. Numerical experiments in case of stenosed artery and in artery with aneurysm (using COMSOL Multiphysics 3.3 are made. The variation of the wall shear stress, which is believed to have a special importance in the rupture of aneurysms, is calculated using both a Newtonian and a non-Newtonian model.

  14. Large Animal Model of Pumpless Arteriovenous Extracorporeal CO₂ Removal Using Room Air via Subclavian Vessels.

    Science.gov (United States)

    Witer, Lucas J; Howard, Ryan A; Trahanas, John M; Bryner, Benjamin S; Alghanem, Fares; Hoffman, Hayley R; Cornell, Marie S; Bartlett, Robert H; Rojas-Peña, Alvaro

    2016-01-01

    End-stage lung disease (ESLD) causes progressive hypercapnia and dyspnea and impacts quality of life. Many extracorporeal support (ECS) configurations for CO2 removal resolve symptoms but limit ambulation. An ovine model of pumpless ECS using subclavian vessels was developed to allow for ambulatory support. Vascular grafts were anastomosed to the left subclavian vessels in four healthy sheep. A low-resistance membrane oxygenator was attached in an arteriovenous (AV) configuration. Device function was evaluated in each animal while awake and spontaneously breathing and while mechanically ventilated with hypercapnia induced. Sweep gas (FiO2 = 0.21) to the device was increased from 0 to 15 L/min, and arterial and postdevice blood gases, as well as postdevice air, were sampled. Hemodynamics remained stable with average AV shunt flows of 1.34 ± 0.14 L/min. In awake animals, CO2 removal was 3.4 ± 1.0 ml/kg/min at maximum sweep gas flow. Respiratory rate decreased from 60 ± 25 at baseline to 30 ± 11 breaths per minute. In animals with induced hypercapnia, PaCO2 increased to 73.9 ± 15.1. At maximum sweep gas flow, CO2 removal was 3.4 ± 0.4 ml/kg/min and PaCO2 decreased to 49.1 ± 6.7 mm Hg. Subclavian AV access is effective in lowering PaCO2 and respiratory rate and is potentially an effective ambulatory destination therapy for ESLD patients.

  15. The impact of {sup 18}F-FDG PET on the management of patients with suspected large vessel vasculitis

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Martin; Rasch, Helmut; Berg, Scott; Ng, Quinn K.T.; Mueller-Brand, Jan; Walter, Martin A. [University Hospital, Institute of Nuclear Medicine, Basel (Switzerland); Briel, Matthias [University Hospital Basel, Institute for Clinical Epidemiology and Biostatistics, Basel (Switzerland); McMaster University, Department of Clinical Epidemiology and Biostatistics, Hamilton, ON (Canada); Daikeler, Thomas; Tyndall, Alan [University Hospital Basel, Department of Rheumatology, Basel (Switzerland); Walker, Ulrich A. [Felix Platter Spital, Department of Rheumatology of Basle University, Basel (Switzerland); Raatz, Heike [University Hospital Basel, Institute for Clinical Epidemiology and Biostatistics, Basel (Switzerland); Jayne, David [Addenbrooke' s Hospital, Vasculitis and Lupus Unit, Cambridge (United Kingdom); Koetter, Ina [University Hospital Tuebingen, Department of Internal Medicine II, Tuebingen (Germany); Blockmans, Daniel [University Hospital Gasthuisberg, Department of General Internal Medicine, Leuven (Belgium); Cid, Maria C.; Prieto-Gonzalez, Sergio [Hospital Clinic, University of Barcelona, IDIBAPS, Department of Systemic Autoimmune Diseases, 08036-Barcelona (Spain); Lamprecht, Peter [University Hospital of Schleswig-Holstein, Department of Rheumatology, Luebeck (Germany); Salvarani, Carlo [Arcispedale S. Maria Nuova, Department of Rheumatology, Reggio Emilia (Italy); Karageorgaki, Zaharenia [Agios Dimitrios General Hospital, 1st Department of Internal Medicine, Thessaloniki (Greece); Watts, Richard [University of East Anglia, Norwich Medical School, Norwich (United Kingdom); Ipswich Hospital NHS Trust, Ipswich (United Kingdom); Luqmani, Raashid [Nuffield Orthopaedic Centre, Department of Rheumatology, Oxford (United Kingdom)

    2012-02-15

    We aimed to assess the impact of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the management of patients with suspected large vessel vasculitis. An international expert panel determined diagnoses and clinical management in patients with suspected large vessel vasculitis, with and without the results of {sup 18}F-FDG PET, respectively. The accuracy of the clinical diagnosis and the resulting clinical management with and without the {sup 18}F-FDG PET results were compared using logistic regression models. The analysis included 30 patients referred to a tertiary care centre with large vessel vasculitis and 31 controls. {sup 18}F-FDG PET had an overall sensitivity of 73.3% [95% confidence interval (CI) 54.1-87.7%], a specificity of 83.9% (95% CI 66.3-94.5%), a positive predictive value of 81.5% (95% CI 61.9-93.7%) and a negative predictive value of 76.5% (95% CI 58.8-89.3%). The diagnostic accuracy of {sup 18}F-FDG PET was higher in patients not receiving immunosuppressive drugs (93.3 vs 64.5%, p = 0.006). Taken in context with other available diagnostic modalities, the addition of {sup 18}F-FDG PET increased the clinical diagnostic accuracy from 54.1 to 70.5% (p = 0.04). The addition of {sup 18}F-FDG PET increased the number of indicated biopsies from 22 of 61 patients (36.1%) to 25 of 61 patients (41.0%) and changed the treatment recommendation in 8 of 30 patients (26.7%) not receiving immunosuppressive medication and in 7 of 31 patients (22.6%) receiving immunosuppressive medication. {sup 18}F-FDG PET is a sensitive and specific imaging tool for large vessel vasculitis, especially when performed in patients not receiving immunosuppressive drugs. It increases the overall diagnostic accuracy and has an impact on the clinical management in a significant proportion of patients. (orig.)

  16. Drug-eluting or bare-metal stents for large coronary vessel stenting? The BASKET-PROVE (PROspective Validation Examination) trial: Study protocol and design

    DEFF Research Database (Denmark)

    Pfisterer, M.; Bertel, O.; Bonetti, P.O.;

    2008-01-01

    Background Based on a subgroup analysis of 18-month BAsel Stent Kosten Effektivitats Trial (BASKET) outcome data, we hypothesized that very late (>12 months) stent thrombosis occurs predominantly after drug-eluting stent implantation in large native coronary vessel stenting. Methods To prove...... stent use in patients with large native vessel stenting. The 2-year death/myocardial infarction-as well as target vessel revascularization-and bleeding rates in these patients with a first-versus second-generation drug-eluting stent should demonstrate the benefit or harm of these stents compared...

  17. Genome-wide association study identifies a variant in HDAC9 associated with large vessel ischemic stroke

    Science.gov (United States)

    2012-01-01

    Genetic factors have been implicated in stroke risk but few replicated associations have been reported. We conducted a genome-wide association study (GWAS) in ischemic stroke and its subtypes in 3,548 cases and 5,972 controls, all of European ancestry. Replication of potential signals was performed in 5,859 cases and 6,281 controls. We replicated reported associations between variants close to PITX2 and ZFHX3 with cardioembolic stroke, and a 9p21 locus with large vessel stroke. We identified a novel association for a SNP within the histone deacetylase 9 (HDAC9) gene on chromosome 7p21.1 which was associated with large vessel stroke including additional replication in a further 735 cases and 28583 controls (rs11984041, combined P = 1.87×10−11, OR=1.42 (95% CI) 1.28-1.57). All four loci exhibit evidence for heterogeneity of effect across the stroke subtypes, with some, and possibly all, affecting risk for only one subtype. This suggests differing genetic architectures for different stroke subtypes. PMID:22306652

  18. Implementation of a practical model for light and heat distribution using laser-induced thermotherapy near to a large vessel

    Energy Technology Data Exchange (ETDEWEB)

    Verhey, J F [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Mohammed, Y [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Ludwig, A [Department of Craneo-Maxillofacial Surgery, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Giese, K [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany)

    2003-11-07

    This paper introduces a simulation model for light and heat transport in tissues including perfusion effects. The model enables an efficient simulation of the damaged zone induced with an optical fibre for laser interstitial thermotherapy (LITT). It is designed specially for, but not limited to, tissue ablation in the neck region near to vessels. We describe in detail the effects of the rise in temperature caused by the absorption of light in tissue, using the heat equation and including the cooling effects of flow in vessels and of microperfusion in tissue in order to determine the extent of thermal damage. The extent of the necrosis zone is calculated with a damage function at each point of a finite element method (FEM) mesh. The FEM mesh is implemented with FEMLAB 2.3 as an add-on for finite element modelling for Matlab 6.5. LITT for tumour ablation in liver and some other anatomical regions is a well-known and established method (Bundesaerztekammer und Kassenaerztliche Bundesvereinigung 2002 Assessment der Bundesaerztekammer und der Kassenaerztlichen Bundesvereinigung, Koeln). Investigations of treatments using LITT in the neck region are still in progress. We propose a refined model to validate the LITT method in the future in another anatomic region, e.g., in the highly sensitive region of the neck. Our calculations show that in order to induce a lesion with a maximum diameter of about 1 cm near to a large vessel, an application time between 3 and 4 min is needed using a laser power of about 10 W with a Nd:YAG 1064 nm radiation wavelength.

  19. 急性肠系膜血管闭塞的诊治经验 (附16例报告)%Diagnosis and Treatment of Acute Mesenteric Vessel Occlusion-A Report of 16 Cases

    Institute of Scientific and Technical Information of China (English)

    栾景源; 董国祥

    2001-01-01

    Objective To investigate the early diagnosis and treatment of the acute mesenteric vessel occlusion(AMVO).Methods In 8 cases of acute mesenteric arterial embolism(MAE), 5 cases were definitely diagnosed, 3 cases were made error diagnosis. One case was treated non-operatively, 1 case was treated by interventional thrombolysis, 4 cases received bowel resection, 1 case received bowel resection after removal of the embolus, the last one avoid bowel resection and short bowel syndrome by the second-look operation. In the 8 cases of acute mesenteric venous thrombosis (MVT), 4 cases were definitely diagnosed, 4 cases were suspected. Two cases were treated non-operatively, 2 cases received bowel resection, the remaining 4 cases received bowel resection after removal of the thrombus.Results In the 8 cases of MAE, 5 were cured and 3 died. All the 8 cases of MVT recovered. Conclusion Early diagnosis was the key to improve the therapeutic effects of AMVO.%目的 探讨急性肠系膜血管闭塞(AMVO)的早期诊断和治疗。方法 8例急性肠系膜动脉栓塞(MAE)确诊5例,误诊3例。保守治疗1例,介入溶栓1例,肠切除4例,取栓后肠切除1例;另1例大部小肠严重缺血,经二次手术探查,避免了肠切除和短肠综合征。8例急性肠系膜静脉血栓形成(MVT)确诊4例,疑诊4例;保守治疗2例,肠切除2例,取栓后肠切除4例。结果 8例MAE治愈5例,死亡3例; 8例MVT全部治愈。结论 对AMVO保持警惕,早期确诊是提高疗效的关键。

  20. Dynamic Response Research of Mooring System for Large-scale Vessels%大型船舶系泊系统的动力响应研究

    Institute of Scientific and Technical Information of China (English)

    徐庭留; 朱克强; 周江华; 蒋卓宏

    2012-01-01

    Through analysis for the load of vessel, the mooring system for the large-scale vessels is introduced, which includes systematic formation, structure, function and characteristics. By combining with the relevant classic formulae in China and abroad, static analysis is used to research wind load, current load on vessels and the load on mooring cable. Based on project examples, calculation is done to find the stress on vessels, identify whether the load on mooring cable is within safe range when berthing vessel is influenced by wind and current factors, evaluate mooring safety level and terminal safety level for the vessel.%通过对大型船舶所受载荷情况的分析,采用静力分析方法结合国内、外有关的经典计算公式,对船舶所受的风载荷、流载荷和缆绳受力情况进行研究.结合具体工程案例,计算船舶的受力情况,以及在风、流作用下系泊时缆绳受力是否在允许的安全范围内,对该船的系泊安全和码头安全做出评价.

  1. Methodological developments in the field of structural integrity analyses of large scale reactor pressure vessels in Hungary

    Directory of Open Access Journals (Sweden)

    Tamás Fekete

    2016-03-01

    Full Text Available Buildings, structures and systems of large scale and high value (e.g. conventional and nuclear power plants, etc. are designed for a certain, limited service lifetime. If the standards and guidelines of the time are taken into account during the design process, the resulting structures will operate safely in most cases. However, in the course of technical history there were examples of unusual, catastrophic failures of structures, even resulting in human casualties. Although the concept of Structural Integrity first appeared in industrial applications only two-three decades ago, its pertinence has been growing higher ever since. Four nuclear power generation units have been constructed in Hungary, more than 30 years ago. In every unit, VVER-440 V213 type light-water cooled, light-water moderated, pressurized water reactors are in operation. Since the mid-1980s, Pressurized Thermal Shock (PTS analyses of Reactor Pressure Vessels (RPV have been conducted in Hungary, where the concept of structural integrity was the basis of research and development. In the first part of the paper, a short historic overview is given, where the origins of the Structural Integrity concept are presented, and the beginnings of Structural Integrity in Hungary are summarized. In the second part, a new conceptual model of Structural Integrity is introduced. In the third part, a brief description of the VVER-440 V213 type RPV and its surrounding primary system is presented. In the fourth part, a conceptual model developed for PTS Structural Integrity Analyses is explained.

  2. [{sup 18}F]FDG-PET in large vessel vasculitis; [{sup 18}F]FDG-PET bei Grossgefaess-Vaskulitiden

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, A.S.D.; Walter, M.A. [Universitaetsspital Basel (Switzerland). Inst. fuer Nuklearmedizin

    2007-06-15

    [{sup 18}F]FDG-PET is a non-invasive metabolic imaging modality based on the regional distribution of fluorine-18-fluorodeoxyglucose that is highly effective in assessing the activity and the extent of giant cell arteritis and Takayasu's arteritis. It has shown to identify more affected vascular regions than morphologic imaging with Magnetic Resonance Imaging in both diseases. A visual grading of vascular [{sup 18}F]FDG-uptake helps to discriminate arteritis from atherosclerosis und therefore provides high specificity. High sensitivity is reached by scanning during the active inflammatory phase. [{sup 18}F]FDG-PET has the potential to develop into a valuable tool in the diagnostic work-up of giant cell arteritis and Takayasu's arteritis, respectively, and might become a first-line investigation technique. Therefore consensus regarding the most favorable imaging procedure as well as further clinical evidence is needed. The purpose of this review is to summarize current information on the present clinical data and to assist nuclear medicine practitioners in recommending, performing and interpreting the results of [{sup 18}F]FDG-PET in patients with suspected large vessel vasculitis. (orig.)

  3. Scanning electron microscopic analysis of endothelial cell coverage and quality in large vessels from multi-organ donors: effects of preservation on endothelial cell integrity.

    Science.gov (United States)

    van Leeuwen, E B; Molema, G; van Luyn, M J; de Jong, K P; Dijk, F; Slooff, M J; Ruiters, M H; van der Meer, J

    2000-06-01

    Endothelial cell integrity (coverage and quality) of large donor vessels is important because these vessels are used for vascular reconstructions in solid-organ transplantation. Disruption of the endothelial cell monolayer will initiate blood coagulation and may lead to thrombosis of large vessels, often resulting in the loss of the transplanted organ. Iliac arteries and veins, removed from 10 heart-beating multi-organ donors at the end of the donor procedure, were analyzed using scanning electron microscopy at three different time points of preservation. Endothelial cell coverage and quality were determined immediately after removal from the donor, after 10 h (time of transplantation) and 7 d storage in 'University of Wisconsin' cold preservation solution (UW). Endothelial cell coverage decreased during the preservation of arteries, but was maintained in veins. Storage of the veins for 7 d in plastic bags showed a decreased endothelial cell coverage compared to storage in glass vials. Early removal of the blood vessels and proper storage, free floating and in clean UW, may improve maintenance of the endothelial cell integrity. These findings may be important in order to reduce the risk of thrombosis and, consequently, organ failure after transplantation. Furthermore, vessels with maintained endothelial cell integrity after 7 d may be used for in vitro research.

  4. Characterizing the relative contributions of large vessels to total ocean noise fields: a case study using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary.

    Science.gov (United States)

    Hatch, Leila; Clark, Christopher; Merrick, Richard; Van Parijs, Sofie; Ponirakis, Dimitri; Schwehr, Kurt; Thompson, Michael; Wiley, David

    2008-11-01

    In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months in 2006. Analysis of received sound levels (10-1000 Hz, root-mean-square pressure re 1 microPa +/- SE) averaged 119.5 +/- 0.3 dB at high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71-141 Hz, root-mean-square pressure re 1 microPa +/- SE) for individual vessels ranged from 158 +/- 2 dB (research vessel) to 186 +/- 2 dB (oil tanker). Tankers were estimated to contribute 2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.

  5. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  6. Experimental verification of bioheat transfer theories: measurement of temperature profiles around large artificial vessels in perfused tissue.

    Science.gov (United States)

    Crezee, J; Lagendijk, J J

    1990-07-01

    The verification of thermal models for use in hyperthermia treatment planning is essential. We investigated the heat transfer between a single vessel and the surrounding vascularised tissue, comparing the conventional bioheat transfer theory and the recently developed keff model using analytical and numerical methods. A plastic tube inserted into the tissue of an isolated perfused organ served as an artificial vessel. This enabled us to vary the blood flow in the vessel and in the tissue independently. The organ used was a bovine kidney, turned into a perfused tissue phantom using an alcohol fixation technique. The temperature profile within the tissue was mapped with constantan-manganin thermocouple wire sensors with a total diameter of 50 microns. The temperature profile relative to the temperature difference between the vessel and organ was measured; increased perfusion caused a reduction of the vessel wall temperature but did not affect the width of the profile. Studying the transient tissue temperature after a step-wise change of the blood temperature in the vessel revealed a faster diffusion of heat at higher perfusion rates. These facts are in accordance with the keff model, but not with the conventional heat-sink theory.

  7. Treatment of hepatocellular carcinoma adjacent to large blood vessels using 1.5T MRI-guided percutaneous radiofrequency ablation combined with iodine-125 radioactive seed implantation

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zheng-Yu, E-mail: linsinlan@yahoo.com.cn [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); Chen, Jin, E-mail: snow8968851@163.com [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); Deng, Xiu-Fen, E-mail: dxf197286@yahoo.com.cn [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China)

    2012-11-15

    Objective: The objective is to study the technology associated with and feasibility of the treatment of hepatocellular carcinoma (HCC) adjacent to large blood vessels using 1.5T MRI-guided radiofrequency ablation combined with iodine-125 (I-125) radioactive seed implantation. Methods: Sixteen patients with a total of 24 HCC lesions (average maximum diameter: 2.35 {+-} 1.03 cm) were pathologically confirmed by biopsy or clinically diagnosed received 1.5T MRI-guided percutaneous radiofrequency ablation (RFA) treatment. Each patient had one lesion adjacent to large blood vessels ({>=}3 mm); after the ablation, I-125 radioactive seeds were implanted in the portions of the lesions that were adjacent to the blood vessels. Results: All the ablations and I-125 radioactive seed implantations were successful; a total of 118 seeds were implanted. The ablated lesions exhibited hypointense signals on the T2WI sequence with a thin rim of hyperintense signals; they also exhibited significant hyperintense signals on the T1WI sequence with clear boundaries. The average follow-up period was 11.1 {+-} 6.2 months. There were 23 complete responses and one partial response in the 24 lesions. The alpha-fetoprotein (AFP) levels of the patients significantly decreased. Conclusion: The 1.5T MRI-guided RFA combined with I-125 radioactive seed implantation for the treatment of HCC adjacent to large blood vessels is an effective technology.

  8. (18)F-FDG PET/CT for the detection of large vessel vasculitis in patients with polymyalgia rheumatica.

    Science.gov (United States)

    Lavado-Pérez, C; Martínez-Rodríguez, I; Martínez-Amador, N; Banzo, I; Quirce, R; Jiménez-Bonilla, J; De Arcocha-Torres, M; Bravo-Ferrer, Z; Jiménez-Alonso, M; López-Defilló, J L; Blanco, R; González-Gay, M A; Carril, J M

    2015-01-01

    Polymyalgia rheumatica (PMR) may present together with large vessel vasculitis (LVV), and frequently requires a more intensive therapy. The aim of the study was to evaluate the impact of (18)F-FDG PET/CT in the diagnosis and management of LVV associated to PMR. This prospective study included 40 consecutive patients (27 women/13 men, 68.10±10.27 years) with PMR and suspicion of associated LVV submitted for (18)F-FDG PET/CT. A PET/CT scan was obtained 180 min after (18)F-FDG intravenous injection. A visual analysis was performed on the images. Five vascular regions were evaluated: supra-aortic trunks (SAT), thoracic aorta (TA), abdominal aorta (AA), iliac arteries (IA), and femoral/tibioperoneal arteries (FTA). The intensity of uptake was graded from 0 to 3. A final diagnosis of LVV was established in 26/40 patients (65%). In the 26 patients with a diagnosis of LVV, the highest intensity of (18)F-FDG uptake was observed in the TA, SAT, and FTA. All of these patients showed uptake at the TA, with grade 2 and 3 in most cases. In 4 of the 14 patients without LVV, no uptake was observed in any vascular region, and in the other 10 patients only a grade 1 uptake was observed in 1 or to 2 territories. Out of the 20 treated LVV patients, (18)F-FDG PET/CT led to a therapeutic change in 17 (85%). (18)F-FDG PET/CT was useful in identifying patients with LVV associated to PMR. The detection of vascular inflammation had an important impact, and led to a change of treatment in a high percentage of patients with LVV. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  9. The role of biological agents in the management of large vessel vasculitis (LVV: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mohammed Osman

    Full Text Available BACKGROUND: Giant cell arteritis (GCA and Takayasu's arteritis (TAA are large vessel vasculitides (LVV for which corticosteroids (CS are the mainstay for treatment. In patients with LVV unable to tolerate CS, biological agents have been used with variable effectiveness. OBJECTIVE: To systematically review the effectiveness and safety of biological agents in patients with LVV. METHODS: We searched 5 electronic databases (inception to October 2012 and conference abstracts with no language restrictions. Two reviewers independently selected studies, extracted data and assessed methodological quality. Our protocol was registered in PROSPERO. RESULTS: We included 25 studies (3 RCTs and 22 case series with ≥2 cases. 95 GCA and 98 TAA patients received biological agents. The RCTs using anti-TNF agents (infliximab, etanercept and adalimumab did not suggest a benefit in GCA. GCA patients receiving tocilizumab, in case series, achieved remission (19 patients and reduction of corticosteroid dose (mean difference, -16.55 mg/day (95% CI: -26.24, -6.86. In case series, 75 patients with refractory TAA treated with infliximab discontinued CS 32% of the time. Remission was variably defined and the studies were clinically heterogeneous which precluded further analysis. CONCLUSION: This systematic review demonstrated a weak evidence base on which to assess the effectiveness of biological treatment in LVV. Evidence from RCTs suggests that anti-TNF agents are not effective for remission or reduction of CS use. Tocilizumab and infliximab may be effective in the management of LVV and refractory TAA, respectively, although the evidence comes from case series. Future analytical studies are needed to confirm these findings.

  10. 3D-black-blood 3T-MRI for the diagnosis of thoracic large vessel vasculitis: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Treitl, Karla Maria; Saam, Tobias [Institute for Clinical Radiology, LMU Munich, Munich (Germany); German Center for Cardiovascular Disease Research (DZHK e.V.), Munich (Germany); Maurus, Stefan; Sommer, Nora Narvina; Coppenrath, Eva; Treitl, Marcus [Institute for Clinical Radiology, LMU Munich, Munich (Germany); Kooijman-Kurfuerst, Hendrik [Philips Healthcare, Hamburg (Germany); Czihal, Michael; Hoffmann, Ulrich [LMU Munich, Division of Vascular Medicine, Medical Clinic and Policlinic IV, Munich (Germany); Dechant, Claudia; Schulze-Koops, Hendrik [LMU Munich, Division of Rheumatology and Clinical Immunology, Medical Clinic and Policlinic IV, Munich (Germany)

    2017-05-15

    To evaluate the feasibility of T1w-3D black-blood turbo spin echo (TSE) sequence with variable flip angles for the diagnosis of thoracic large vessel vasculitis (LVV). Thirty-five patients with LVV, diagnosed according to the current standard of reference, and 35 controls were imaged at 3.0T using 1.2 x 1.3 x 2.0 mm{sup 3} fat-suppressed, T1w-3D, modified Volumetric Isotropic TSE Acquisition (mVISTA) pre- and post-contrast. Applying a navigator and peripheral pulse unit triggering (PPU), the total scan time was 10-12 min. Thoracic aorta and subclavian and pulmonary arteries were evaluated for image quality (IQ), flow artefact intensity, diagnostic confidence, concentric wall thickening and contrast enhancement (CWT, CCE) using a 4-point scale. IQ was good in all examinations (3.25 ± 0.72) and good to excellent in 342 of 408 evaluated segments (83.8 %), while 84.1 % showed no or minor flow artefacts. The interobserver reproducibility for the identification of CCE and CWT was 0.969 and 0.971 (p < 0.001) with an average diagnostic confidence of 3.47 ± 0.64. CCE and CWT were strongly correlated (Cohen's k = 0.87; P < 0.001) and significantly more frequent in the LVV-group (52.8 % vs. 1.0 %; 59.8 % vs. 2.4 %; P < 0.001). Navigated fat-suppressed T1w-3D black-blood MRI with PPU-triggering allows diagnosis of thoracic LVV. (orig.)

  11. Large-vessel thrombosis in intestinal Beh(c)et's disease complicated with myelodysplastic syndrome and trisomy 8

    Institute of Scientific and Technical Information of China (English)

    Huang-Chi Chen; Ying-Ming Chiu

    2012-01-01

    Beh(c)et's disease is characterized by recurrent oral ulcers,genital ulcers,uveitis and skin lesions.Myelodysplastic syndrome (MDS) is characterized by problems due to ineffective hematopoiesis.Several studies have identified a relationship between MDS and Beh(c)et's disease,especially intestinal Beh(c)et's disease.Trisomy 8 seems to play an important role in these disorders as well.The present case was a 24-year-old woman who had a huge tonsil ulcer with initial symptoms of odynophagia and intermittent fever.We also noted folliculitis on her upper back.Five days later,she began to experience diarrhea and abdominal pain.Abdominal computed tomography and subsequent surgery revealed ileum perforation and enterocolitis with multiple ulcers.Later,she was admitted again for a vulvar suppurative ulcer and suspicious Bartholin's cyst infection.The patient's clinical presentations met the criteria for Beh(c)et's disease.Six months after the bowel perforation event,we noted the development of pancytopenia in a routine laboratory examination.All the examinations led to the diagnosis of MDS with trisomy 8.The most unusual finding was that multiple large vessel thrombi developed during follow-up.Previous studies have suggested that trisomy 8 in MDS leads to concurrent intestinal Beh(c)et's disease.Moreover,the inflammatory and immune genes related to thrombus formation are overexpressed in cases of MDS with trisomy 8.Trisomy 8 must play a role in thrombosis.Further studies are needed to help clarify the pathophysiology and pathogenesis of these disorders.

  12. Lingualized occlusion. An occlusion for all reasons.

    Science.gov (United States)

    Parr, G R; Ivanhoe, J R

    1996-01-01

    This authors make practical recommendations for a wide variety of clinical situations, including various anteroposterior and buccolingual arch discrepancies. Many of the ideals of the anatomical and mechanical schools of thought are blended. In addition to being a valuable clinical adjunct, Lingualized Occlusion also has great application in undergraduate dental education. It is a simpler occlusal scheme to teach and learn.

  13. Acute arterial occlusion - kidney

    Science.gov (United States)

    Acute renal arterial thrombosis; Renal artery embolism; Acute renal artery occlusion; Embolism - renal artery ... kidney can often result in permanent kidney failure. Acute arterial occlusion of the renal artery can occur after injury or trauma to ...

  14. Histamine H3 and H4 receptor ligands modify vascular histamine levels in normal and arthritic large blood vessels in vivo.

    Science.gov (United States)

    Kyriakidis, Konstantinos; Zampeli, Evangelia; Palaiologou, Marina; Tiniakos, Dina; Tiligada, Ekaterini

    2015-01-01

    Growing evidence associates histamine with arthritis, but its implication in shaping vascular function in chronic inflammation remains largely elusive. This study explored the involvement of vascular histamine in the extra-articular responses in peripheral large blood vessels using a rat model of adjuvant-induced arthritis. Histamine levels were increased in the abdominal aorta and the inferior vena cava of arthritic animals. Contrary to the H1 receptor antagonist dimetindene, histamine induction was observed following administration of the H3 and H4 receptor ligands GSK334429 and JNJ7777120, respectively. In arthritis, prophylactic treatment with GSK334429 partially attenuated the clinical signs and restored basal histamine levels only in the abdominal aorta. This study is the first to implicate the H3 and H4 receptors in a concerted constitutive regulation of basal vascular histamine in the rat large blood vessels and to identify the H3 receptor as a component that may influence arterial histamine during the onset of arthritis.

  15. Late recurrence of a completely occluded large intracranial aneurysm treated with a Tubridge flow diverter.

    Science.gov (United States)

    Zhang, Xiaoxi; Lv, Nan; Wang, Chi; Cao, Wei; Liu, Jianmin; Huang, Qinghai

    2017-02-01

    We report a rare case of recurrence of a large intracavernous aneurysm after angiography proved complete occlusion. The aneurysm was treated by a combination of a Tubridge flow diverter and coils, and balloon angioplasty, after flow diverter devices deployment for parent vessel stenosis. Six month angiographic follow-up demonstrated complete occlusion. Unfortunately, obvious aneurysm recurrence was confirmed on 2 year angiographic follow-up. The probable mechanism of recurrence was analyzed.

  16. Non-uniform object counting method in large-format pyramid images applied to CD31 vessel counting in whole-mount digital pathology sections

    Science.gov (United States)

    Murray, Mayan; Hill, Melissa L.; Liu, Kela; Mainprize, James G.; Yaffe, Martin J.

    2016-03-01

    Whole-mount pathology imaging has the potential to revolutionize clinical practice by preserving context lost when tissue is cut to fit onto conventional slides. Whole-mount digital images are very large, ranging from 4GB to greater than 50GB, making concurrent processing infeasible. Block-processing is a method commonly used to divide the image into smaller blocks and process them individually. This approach is useful for certain tasks, but leads to over-counting objects located on the seams between blocks. This issue is exaggerated as the block size decreases. In this work we apply a novel technique to enumerate vessels, a clinical task that would benefit from automation in whole-mount images. Whole-mount sections of rabbit VX2 tumors were digitized. Color thresholding was used to segment the brown CD31- DAB stained vessels. This vessel enumeration was applied to the entire whole-mount image in two distinct phases of block-processing. The first (whole-processing) phase used a basic grid and only counted objects that did not intersect the block's borders. The second (seam-processing) phase used a shifted grid to ensure all blocks captured the block-seam regions from the original grid. Only objects touching this seam-intersection were counted. For validation, segmented vessels were randomly embedded into a whole-mount image. The technique was tested on the image using 24 different block-widths. Results indicated that the error reaches a minimum at a block-width equal to the maximum vessel length, with no improvement as the block-width increases further. Object-density maps showed very good correlation between the vessel-dense regions and the pathologist outlined tumor regions.

  17. FDG-PET in patients with fever of unknown origin: the importance of diagnosing large vessel vasculitis.

    Science.gov (United States)

    Meller, J; Sahlmann, C O; Gürocak, O; Liersch, T; Meller, B

    2009-02-01

    This review analyzes the impact of 2-[(18)F]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) in the diagnostic work-up of classic fever of unknown origin (FUO) according to the criteria first proposed by Petersorf in 1961 and later modified by Durack et al. in 1991. Algorithms currently used in this diagnostic process are not strictly evidence based up to now. FDG accumulates in malignant tissues, but also in inflammatory cells by the overexpression of facultative glucose transporter-isotypes (mainly GLUT-1 and GLUT-3) and by an overproduction of glycolytic enzymes. Therefore, this technique covers a broad spectrum of possible etiologies for FUO. Once imaged, these lesions can be further investigated by other (e.g. invasive) and more specific methods. Until now, four prospective studies using FDG-PET in patients with classic FUO, encompassing 167 patients in total are published. Three retrospective studies with 125 patients are also available. These studies are discussed and weighted according to the control of selection-bias that was performed. An interstudy-bias may also be present resulting from a considerable variability in causes of FUO. A low number of diagnostic scans in a study may sometimes be related to a high rate of fevers caused by miscellaneous disorders or to a high rate of undiagnosed patients. In these disease categories, focal pathologies that can be imaged with FDG-PET, are rare. A high number of diagnostic scans is always related to a high prevalence of patients with medium- and large-vessel vasculitis. Available data indicate that FDG-PET has the potential to play an important role as a second line procedure in the management of about 1/3 of patients with classic FUO. It is expected that hybrid imaging (PET/computed tomography [CT]; PET/magnetic resonance imaging [MRI]) will improve the diagnostic impact of FDG-PET further, but prospective data about the value of this methods are currently not available. The question as to how

  18. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Science.gov (United States)

    2010-10-01

    ... (362.8 mt) carrying capacity in the ETP may be labeled dolphin-safe only if the following requirements...) carrying capacity and presented for import into the United States may be labeled dolphin-safe only if the... seine vessels of greater than 400 st (362.8 mt) carrying capacity and presented for import into...

  19. Occlusion: an orthodontic perspective.

    Science.gov (United States)

    Kasrovi, P M; Meyer, M; Nelson, G D

    2000-10-01

    In recent years, orthodontists have examined their concepts of occlusion. In current literature, at professional meetings, and in continuing education courses, one hears an ongoing discussion of condylar position and mandibular border movements in relation to occlusion. There is a wide variation in opinion as to whether dental occlusion and TMJ function are interdependent. The authors have adopted a dynamic concept of dental function to replace the traditional static view of molar relationship and incisor overlap. This article discusses how occlusion has evolved in orthodontics and reviews Andrews' six keys to ideal static occlusion, the goals of ideal dynamic occlusion, and the six signs of developing malocclusions. The authors also review the literature on the relationship between orthodontics, occlusion, and TMD.

  20. [Occlusion, articulated and articulation].

    Science.gov (United States)

    De Boever, J A

    1990-01-01

    In this paper the so-called 'normal' or 'ideal' occlusal relationships are described in static centric as well as in dynamic, eccentric positions. However, difference is made between the different occlusal concepts. There is no real antagonism between the 'physiologic occlusal concept' in natural dentition and the 'therapeutic occlusal concept' on which the treatment should be based in restoring the occlusion. The different forms of occlusion and articulation found in the natural dentition are the expression of physiologic, biological variations. The rest position of the mandible is an unreliable reference point in occlusal rehabilitation. Moderate attrition in older patients should not be considered as pathologic and there is no indication for treatment in absence of functional pathology.

  1. Radioisotopic imaging in large vessel vasculitis; Apport de l'imagerie radioisotopique dans l'arterite inflammatoire des gros vaisseaux

    Energy Technology Data Exchange (ETDEWEB)

    Huglo, D.; Lambert, M.; Hachulla, E.; Hatron, P.Y.; Steinling, M. [Lille Univ. Nord-de-France, 59 - Lille (France); Huglo, D.; Raynaud, F.; Petyt, G.; Prangere, T.; Steinling, M. [CHU de Lille, Service de Medecine Nucleaire et Imagerie Fonctionnelle, Hopital Huriez, 59 - Lille (France); Huglo, D. [Inserm U703, 59 - Lille (France); Lambert, M.; Hachulla, E.; Hatron, P.Y. [CHU de Lille, Service de Medecine Interne, 59 - Lille (France)

    2009-08-15

    The group of large vessel vasculitis includes giant cell arthritis and Takayasu disease. If mono photonic nuclear medicine can sometimes show some unusual patterns in these diseases, positron emission tomography with fluorodeoxyglucose seems have a special attract and provide some indications during the monitoring of these patients. However, most of these indications remain to be validated, specially to differentiate weak vascular wall inflammatory activities from physiological and/or atherosclerotic accumulation. (authors)

  2. Large particulate allergens can elicit mast cell-mediated anaphylaxis without exit from blood vessels as efficiently as do small soluble allergens.

    Science.gov (United States)

    LiHua, Li; Yoshikawa, Soichiro; Ohta, Takuya; Horiguchi, Kayo; Kawano, Yohei; Ohtsu, Hiroshi; Yamanishi, Yoshinori; Karasuyama, Hajime

    2015-11-06

    Anaphylaxis is a rapid-onset, life-threatening allergic reaction in that IgE, mast cells and histamine are commonly involved. It can be experimentally induced in IgE-sensitized animals by intravenous injection of corresponding allergens, and the sign of anaphylactic reaction can be detected within minutes after allergen challenge. However, it remains puzzling why the anaphylactic reaction can be initiated in vivo so quickly, considering that allergens are delivered into the blood circulation while mast cells reside within peripheral tissues but not in the blood circulation. To address this issue, we compared two different forms of the same allergen, small soluble and large particulate ones, in their ability to induce anaphylaxis in IgE-sensitized mice. In contrast to our expectation, particulate allergens could induce anaphylaxis as quickly and efficiently as did soluble allergens, even though they remained inside of blood vessels. In vivo imaging analysis suggested the direct interaction of intravascular particulate allergens and perivascular mast cells across the capillary wall. Taken together with previous report that perivascular mast cells can capture IgE in the blood circulation by extending cell processes across the vessel wall, our findings imply that blood-circulating allergens, regardless of their size, can stimulate mast cells without exit from blood vessels, by means of cross-linking IgE on mast cell processes inserted into the vessel lumen, and hence initiate anaphylactic reaction so quickly.

  3. A genetic study of Factor V Leiden (G1691A) mutation in young ischemic strokes with large vessel disease in a South Indian population.

    Science.gov (United States)

    Anadure, Ravi; Christopher, Rita; Nagaraja, Dindagur; Narayanan, Coimbatore

    2017-10-01

    Factor V Leiden (FVL) has been, by far, the most investigated gene mutation, with 26 studies to date, on its role in arterial strokes. Overall, a meta-analysis of all these studies taken together showed that carriers of the Factor V Leiden allele were 1.33times more likely to develop arterial strokes when compared to controls. We subjected a highly select subset of young strokes, with large vessel infarcts, to genetic analysis for FVL mutation and compared them with matched healthy controls to look for a statistically significant association. In this prospective study, 6/120 cases (5%) and 2/120 controls (1.6%) were positive for heterozygous FVL (G1691A) mutation. The higher prevalence of FVL mutation in cases (5%) compared to controls (1.6%) did not show statistical significance with a Pearson's Chi square P value of 0.15. The Odds Ratio (OR) for risk of large vessel disease in FVL positive cases was 3.10 (95% CI of 0.61-15.7). FVL mutation (G1691A) in young Indian subjects with ischemic strokes does not seem to be significantly associated with large vessel disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Closing the gap between coil and balloon in the neurointerventional armamentarium? Initial clinical experience with a nitinol vascular occlusion plug

    Energy Technology Data Exchange (ETDEWEB)

    Gralla, Jan; Schroth, Gerhard; El-Koussy, Marwan; Brekenfeld, Caspar [University of Bern, Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern (Switzerland); Kickuth, Ralph [Interventional and Pediatric Radiology, Department of Diagnostic, Bern (Switzerland); Do, Dai-Do [University of Bern, Department of Angiology, Inselspital, Bern (Switzerland)

    2008-08-15

    The use of vascular plug devices for the occlusion of high-flow lesions is a relatively new and successful procedure in peripheral and cardiopulmonary interventions. We report on the use and efficiency of the Amplatzer vascular plug in a small clinical series and discuss its potential for occlusion of large vessels and high-flow lesions in neurointerventions. Between 2005 and 2007 four patients (mean age 38.5 years, range 16-62 years) were treated with the device, in three patients to achieve parent artery occlusion of the internal carotid artery, in one patient to occlude a high-flow arteriovenous fistula of the neck. The application, time to occlusion, and angiographic and clinical results and the follow-up were evaluated. Navigation, positioning and detachment of the device were satisfactory in all cases. No flow-related migration of the plug was seen. The cessation of flow was delayed by a mean of 10.5 min after deployment of the first device. In the procedures involving vessel sacrifice, two devices had to be deployed to achieve total occlusion. No patient experienced new neurological deficits; the 3-month follow-up revealed stable results. The Amplatzer vascular plug can be adapted for the treatment of high-flow lesions and parent artery occlusions in the head and neck. In this small series the use of the devices was uncomplicated and safe. The rigid and large delivery device and the delayed cessation of flow currently limit the device's use in neurointerventions. (orig.)

  5. Hipervolemia mais tríplice oclusão vascular no tratamento da lesão traumática da veia cava retro-hepática e veias hepáticas Hypervolemia and triple vessel occlusion in the treatment of traumatic retrohepatic vena and hepatic vein injuries

    Directory of Open Access Journals (Sweden)

    Wilson Luiz Abrantes

    2001-10-01

    Full Text Available BACKGROUND: Liver vascular isolation is essential for the treatment of the retrohepatic vena cava and hepatic veins. Triple vessel occlusion (TVO - occlusion of the portal triad, the inferior vena cava above the renal veins and within the pericardium is the easiest isolation method for the surgeon. Unfortunately, this technique cannot be applied to hypovolemic and/or shock (cardiac arrest patients as it compromises venous return. OBJECTIVES: Our objective is to demonstrate that in the above mentioned patients, establishing a previous hypervolemic state allows the safe use of TVO. METHODS: The method includes efficient injury tamponade with aggressive fluid replacement until normal blood volume is reached (resuscitation. Normal blood volume is recognized by a return of arterial blood pressure to normal levels, inferior vena cava filling and an increase in aortic wall tension. Following this procedure, hypervolemia is obtained by the rapid additional infusion of 1.500 to 2.000 ml of fluids. TVO in this situation does not alter the heart rhythm and maintains a clear operative field which is essential for hepatotomy, venorrhaphy and or venous ligation. RESULTS: Three patients were successfully operated.

  6. A software application for comparing large numbers of high resolution MALDI-FTICR MS spectra demonstrated by searching candidate biomarkers for glioma blood vessel formation

    Directory of Open Access Journals (Sweden)

    Smitt Peter

    2008-03-01

    Full Text Available Abstract Background A Java™ application is presented, which compares large numbers (n > 100 of raw FTICR mass spectra from patients and controls. Two peptide profile matrices can be produced simultaneously, one with occurrences of peptide masses in samples and another with the intensity of common peak masses in all the measured samples, using the peak- and background intensities of the raw data. In latter way, more significantly differentially expressed peptides are found between groups than just using the presence or absence in samples of common peak masses. The software application is tested by searching angiogenesis related proteins in glioma by comparing laser capture micro dissected- and enzymatic by trypsin digested tissue sections. Results By hierarchical clustering of the presence-absence matrix, it appears that proteins, such as hemoglobin alpha and delta subunit, fibrinogen beta and gamma chain precursor, tubulin specific chaperone A, epidermal fatty acid binding protein, neutrophil gelatinase-associated lipocalin precursor, peptidyl tRNA hydrolase 2 mitochondrial precursor, placenta specific growth hormone, and zinc finger CCHC domain containing protein 13 are significantly different expressed in glioma vessels. The up-regulated proteins in the glioma vessels with respect to the normal vessels determined by the Wilcoxon-Mann-Whitney test on the intensity matrix are vimentin, glial fibrillary acidic protein, serum albumin precursor, annexin A5, alpha cardiac and beta actin, type I cytoskeletal 10 keratin, calcium binding protein p22, and desmin. Peptide masses of calcium binding protein p22, Cdc42 effector protein 3, fibronectin precursor, and myosin-9 are exclusively present in glioma vessels. Some peptide fragments of non-muscular myosin-9 at the C-terminus are strongly up-regulated in the glioma vessels with respect to the normal vessels. Conclusion The less rigorous than in general used commercial propriety software de

  7. Low-molecular-weight heparin versus aspirin for acute ischemic stroke with large artery occlusive disease: subgroup analyses from the Fraxiparin in Stroke Study for the treatment of ischemic stroke (FISS-tris) study.

    Science.gov (United States)

    Wang, Qiao Shu; Chen, Christopher; Chen, Xiang Yan; Han, Jing Hao; Soo, Yannie; Leung, Thomas W; Mok, Vincent; Wong, Ka Sing Lawrence

    2012-02-01

    The Fraxiparin in Stroke Study for the treatment of ischemic stroke (FISS-tris) study showed no superiority of low-molecular-weight heparin (LMWH) over aspirin for the primary end point (Barthel Index) in acute ischemic stroke due to large artery occlusive disease. This study aims to evaluate the efficacy of LMWH and aspirin in selected subgroups so as to generate hypotheses for further studies. The FISS-tris study was a multicenter, randomized trial to investigate the efficacy and safety of LMWH (nadroparin calcium 3800 antifactor Xa IU/0.4 mL subcutaneously twice daily) or aspirin (160 mg once daily) for the treatment of patients with acute ischemic stroke and large artery occlusive disease. The primary outcome was the Barthel Index score dichotomized at 85 6 months poststroke. Exploratory subgroup analysis was performed using different levels of baseline characteristics and the distribution of symptomatic arteries. Compared with aspirin, LMWH improved outcome among older patients >68 years (P=0.043; OR, 1.86; 95% CI, 1.02-3.41) without ongoing antiplatelet treatment on admission (P=0.029; OR, 1.85; 95% CI, 1.06-3.21) and with symptomatic posterior circulation arterial disease (P=0.001; OR, 5.76; 95% CI, 2.00-16.56). Our findings suggest that LMWH may be of benefit in certain subgroups of patients with acute cerebral infarct and large artery occlusive disease. Hence, further investigation of LMWH may be justified in subgroups such as the elderly, nonusers of antiplatelet agents, and patients with posterior circulation stenosis. URL: www.strokecenter.org/trials. Unique identifier: registration no. 493.

  8. On hull form of large deep-water seismic survey vessels%大型深水物探船船型研究

    Institute of Scientific and Technical Information of China (English)

    付学辉

    2015-01-01

    介绍国际上大型物探船的船型发展情况及其主要作业特点.结合我国近年新建的大型物探船,分析该船型在总布置、性能指标、谐波控制、水下噪声等方面的技术难点.%This paper introduces the major development and the main operation characteristics of the large seismic survey vessels in the world. Based on the vessels recently built in China, it analyzes the technique issues about general arrangement, ship performance, harmonic wave control and subsea noise.

  9. Central retinal vein occlusion concomitant with dengue fever

    OpenAIRE

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Background Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengu...

  10. Central retinal vein occlusion concomitant with dengue fever

    OpenAIRE

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Background Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengu...

  11. Detecting natural occlusion boundaries using local cues

    Science.gov (United States)

    DiMattina, Christopher; Fox, Sean A.; Lewicki, Michael S.

    2012-01-01

    Occlusion boundaries and junctions provide important cues for inferring three-dimensional scene organization from two-dimensional images. Although several investigators in machine vision have developed algorithms for detecting occlusions and other edges in natural images, relatively few psychophysics or neurophysiology studies have investigated what features are used by the visual system to detect natural occlusions. In this study, we addressed this question using a psychophysical experiment where subjects discriminated image patches containing occlusions from patches containing surfaces. Image patches were drawn from a novel occlusion database containing labeled occlusion boundaries and textured surfaces in a variety of natural scenes. Consistent with related previous work, we found that relatively large image patches were needed to attain reliable performance, suggesting that human subjects integrate complex information over a large spatial region to detect natural occlusions. By defining machine observers using a set of previously studied features measured from natural occlusions and surfaces, we demonstrate that simple features defined at the spatial scale of the image patch are insufficient to account for human performance in the task. To define machine observers using a more biologically plausible multiscale feature set, we trained standard linear and neural network classifiers on the rectified outputs of a Gabor filter bank applied to the image patches. We found that simple linear classifiers could not match human performance, while a neural network classifier combining filter information across location and spatial scale compared well. These results demonstrate the importance of combining a variety of cues defined at multiple spatial scales for detecting natural occlusions. PMID:23255731

  12. Cephalometric analysis for functional occlusion

    Directory of Open Access Journals (Sweden)

    Ashok Karad

    2016-01-01

    Full Text Available Background: Various elements contributing to good functional occlusion have not been clearly assessed with cephalometrics for the diagnosis of functional problems and their application in clinical practice. The aim of this study, therefore, was to analyze different components of functional occlusion to formulate concise functional cephalometric analysis. Materials and Methods: Eighty-two cases (38 males and 44 females, with class I occlusion and balanced facial profile, were examined based on the selection criteria, and cephalograms were taken in natural head position. All the radiographs were then analyzed using various functional parameters. Results: The mean values of condylar path angle and incisal path angle were 55.83° and 65.67°, respectively, with large deviations. However, both showed positive correlation. The value of the angle of long axis of mandibular incisor with respect to the line joining center of condyle and lower incisor tip was 88.04°. Moreover, the angle between the occlusal plane and horizontal plane was 12.88°. In vertical plane, lower face height (LFH was found to be slightly less than the upper face height. Maxilla contributed around 45% of the LFH while mandible formed about 60%. Furthermore, upper alveolar component (maxillary alveolar height formed more than half of the maxilla (53.79% whereas lower alveolar component (mandibular alveolar height was 74.8% of the mandible. Conclusion: This study has analyzed various components of functional occlusion and formulated a concise functional cephalometric analysis for diagnosis, treatment planning, and assessment of treatment results.

  13. Vascular Reactivity: Evaluation of an acute suprasystolic occlusion with impedance plethysmography

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, M C [Departamento de BioingenierIa, Facultad de Ciencias Exactas y TecnologIa, Universidad Nacional de Tucuman e INSIBIO, CONICET, Tucuman (Argentina); Bonaudo, M; Conde, A [Carrera de Ingenieria de Biomedica, Facultad de Ciencias Exactas y TecnologIa, Universidad Nacional de Tucuman (Argentina); Palavecino, L [Carrera de Ingenieria de Biomedica, Facultad de Ciencias Exactas y TecnologIa, Universidad Nacional de Tucuman (Argentina)

    2007-11-15

    In the clinical set, the evaluation of endothelium- dependent vasodilator response of large vessels is carried out using ultrasound equipment for vascular flow determinations and during administration of vasoactive drugs. This work proposes to use a substantially cheaper technique and a sustained cuff arterial occlusion in order to cause vasodilation. Impedance plethysmography is used to detect the arterial pulse wave over radial artery while the forearm is occluded by above the recording site. From these plethysmographic waves, three indexes and their changes -between control and maximal response post-occlusion- were calculated. 33 complete records obtained from healthy low-risk volunteers were analyzed. Between control and post-occlusion maximal response, 'average percentual change of pulse wave amplitude' were (35{+-}13)%, 'stiffness index' did not show significant differences (6,38{+-}0,98 vs 6,38{+-}0,94 and 'reflection index' was significant lower (58{+-}15 vs 35{+-}16)%. These results indicate that: 1- cuff occlusion maneuver was effective to cause endothelium-dependent vasodilation, 2-changes of pulse wave amplitude and reflection index could be used as markers of athero-arteriosclerotic damage in the vascular bed, even in sub-clinical conditions.

  14. 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...

  15. Temporomandibular disorders and occlusion.

    Science.gov (United States)

    Badel, Tomislav; Marotti, Miljenko; Pavicin, Ivana Savić; Basić-Kes, Vanja

    2012-09-01

    Occlusion has an important place within the multifactorial concept of the temporomandibular disorder (TMD) etiopathogenesis as well as in every form of dental treatment. The modern concept of treatment of these disorders differentiates initial and definitive forms of treatment. The aim of this paper is to analyze recent viewpoints on the role of occlusion in the etiopathogenesis and treatment ofTMDs. Masticatory muscles and temporomandibular joints are directly connected with occlusal relations and TMDs are traditionally linked with occlusal disorders. The initial occlusal treatment can be applied to all TMD patients, regardless of their having intact teeth with respect to physiological occlusal relations and in patients in need of orthodontic or prosthodontic treatment or an oral surgical procedure. On managing TMD patients, there are doubts about the indications for definitive treatment and whether there has been a possibility of treating a painful TMD by reversible treatment modalities, that is, by initial treatment. Other types of orofacial pain such as trigeminal neuralgia can be comorbid with TMDs but also result in unnecessary procedures on the teeth and prosthodontic work if they are not recognized. Although dental profession mainly recognizes the importance of occlusal treatment of TMD problems, their relationship is controversial because it is not strictly demonstrated in numerous scientific studies. Occlusion is not the dominant cause of TMD problems.

  16. Occlusion effects, Part II

    DEFF Research Database (Denmark)

    Hansen, Mie Østergaard

    The present report studies the mechanism of the occlusion effect by means of literature studies, experiments and model estimates. A mathematical model of the occlusion effect is developed. The model includes the mechanical properties of the earmould and the airborne sound as well as the body...

  17. Research vessels

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, P.S.

    The role of the research vessels as a tool for marine research and exploration is very important. Technical requirements of a suitable vessel and the laboratories needed on board are discussed. The history and the research work carried out...

  18. High Blood Pressure Increases the Risk of Poor Outcome at Discharge and 12-month Follow-up in Patients with Symptomatic Intracranial Large Artery Stenosis and Occlusions: Subgroup analysis of the CICAS Study.

    Science.gov (United States)

    Yu, Dan-Dan; Pu, Yue-Hua; Pan, Yue-Song; Zou, Xin-Ying; Soo, Yannie; Leung, Thomas; Liu, Li-Ping; Wang, David Z; Wong, Ka-Sing; Wang, Yi-Long; Wang, Yong-Jun

    2015-06-01

    The purpose of this study was to discuss the relationship between blood pressure and prognosis of patients with symptomatic intracranial arterial stenosis. Data on 2426 patients with symptomatic intracranial large artery stenosis and occlusion who participated in the Chinese Intracranial Atherosclerosis (CICAS) study were analyzed. According to the JNC 7 criteria, blood pressure of all patients was classified into one of the four subgroups: normal, prehypertension, hypertension stage I, and hypertension stage II. Poor outcomes were defined as death and functional dependency (mRS 3-5) at discharge or at 1 year. For patients with intracranial stenosis of 70% to 99%, the rate of poor outcome at discharge was 19.3%, 23.5%, 26.8%, and 39.8% (P = 0.001) for each blood pressure subgroup. For patients with intracranial large artery occlusion, the rates were 17.6%, 22.1%, 29.5%, and 49.8%, respectively (P blood pressure subgroup and 11.6%, 21.5%, 23.9%, 35.1% (P risk of poor outcome at discharge and 12-month follow-up. © 2015 The Authors. CNS Neuroscience & Therapeutics Published by John Wiley & Sons Ltd.

  19. A New Occlusion Device: Application of the ArtVentive Endoluminal Occlusion System (EOS)—First in Human Clinical Trial

    Energy Technology Data Exchange (ETDEWEB)

    Venbrux, Anthony C., E-mail: avenbrux@mfa.gwu.edu [The George Washington University Medical Center, Division of Vascular and Interventional Radiology (United States); Rudakov, Leon, E-mail: leonrudakov@artventivemedical.com [Artventive Medical Group, Inc. (United States); Plass, Andre, E-mail: andre.plass@usz.ch; Emmert, Maximilian Y., E-mail: maximilian.emmert@usz.ch [University Hospital Zurich, Clinic for Cardiac and Vascular Surgery (Switzerland); Ebner, Adrian, E-mail: adrianebner@fundacor.com.py [Sanatorio Privado Santa Clara, Cath Lab Department (Paraguay)

    2013-05-24

    PurposeThe purpose of this study was to determine the safety and efficacy of a new endoluminal occlusion device, ArtVentive endoluminal occlusion system (EOS), to occlude the spermatic vein in symptomatic males with varicoceles.MethodsThe ArtVentive EOS device has been developed for percutaneous, peripheral occlusion of the peripheral arterial and venous vasculature. The system is comprised of an implantable occlusion device and a delivery catheter. At present, there are two device sizes: (a) size 1 for target vessels ranging between 3.5 and 5.5 mm in diameter, and (b) size 2 for target vessels 5.5–8.5 mm in diameter. The treatment group included six adult males, ages 22–34 years. Nine target vessels were occluded. A total of 20 devices were implanted in six subjects.ResultsThe acute occlusion rate at the end of the procedure was 100 % occurring in nine of nine vessels. The spermatic veins of all patients remained occluded on venography at 30 days follow-up. Pain scores related to varicoceles decreased in five of six patients.ConclusionsAlthough we recognize this study is limited, initial experience indicates that the ArtVentive EOS is a safe and effective new device for occlusion of vessels (varicoceles). The device has potential applications in other clinical conditions requiring occlusion of veins or arteries.

  20. The prognostic value of baseline {sup 18}F-FDG PET/CT in steroid-naive large-vessel vasculitis: introduction of volume-based parameters

    Energy Technology Data Exchange (ETDEWEB)

    Dellavedova, L. [Ospedale Civile di Legnano, PET/CT Center - Nuclear Medicine Department, Legnano (Italy); University of Milan, Department of Health Sciences, Milan (Italy); Carletto, M.; Maffioli, L.S. [Ospedale Civile di Legnano, PET/CT Center - Nuclear Medicine Department, Legnano (Italy); Faggioli, P.; Sciascera, A.; Mazzone, A. [Ospedale Civile di Legnano, Internal Medicine Department, Legnano (Italy); Del Sole, A. [University of Milan, Department of Health Sciences, Milan (Italy)

    2016-02-15

    The aim of this study was to analyse if the result of a baseline {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT scan, in large-vessel vasculitis (LVV) patients, is able to predict the course of the disease, not only in terms of presence/absence of final complications but also in terms of favourable/complicated progress (response to steroid therapy, time to steroid suspension, relapses, etc.). A total of 46 consecutive patients, who underwent {sup 18}F-FDG PET/CT between May 2010 and March 2013 for fever of unknown origin (FUO) or suspected vasculitis (before starting corticosteroid therapy), were enrolled. The diagnosis of LVV was confirmed in 17 patients. Considering follow-up results, positive LVV patients were divided into two groups, one characterized by favourable (nine) and the other by complicated progress (eight), on the basis of presence/absence of vascular complications, presence/absence of at least another positive PET/CT during follow-up and impossibility to comply with the tapering schedule of the steroid due to biochemical/symptomatic relapse. Vessel uptake in subjects of the two groups was compared in terms of intensity and extension. To evaluate the extent of active disease, we introduced two volume-based parameters: ''volume of increased uptake'' (VIU) and ''total lesion glycolysis'' (TLG). The threshold used to calculate VIU on vessel walls was obtained by the ''vessel to liver'' ratio by means of receiver-operating characteristic analysis and was set at 0.92 x liver maximum standardized uptake value in each patient. Measures of tracer uptake intensity were significantly higher in patients with complicated progress compared to those with a favourable one (p < 0.05). Measures of disease extension were even more significant and TLG emerged as the best parameter to separate the two groups of patients (p = 0.01). This pilot study shows that, in LVV patients, the

  1. Occlusion effects, Part I

    DEFF Research Database (Denmark)

    Hansen, Mie Østergaard

    in a questionnaire based on their daily experience with their personal hearing aid. It turned out that 73% of these persons experienced a change in own voice, but both occlusion effects of acoustic, mechanical and biological origin were experienced. The same persons came into Oticon's clinic, where their hearing aid...... fitting and occlusion effect were evaluated. Occlusion effect was measured as the difference in real ear sound pressure level with and without hearing aid while the person was speaking. It was done both with the hearing aid turned off and with the hearing aid turned on. Relations between their experienced...

  2. Follicular occlusion tetrad

    Directory of Open Access Journals (Sweden)

    Vani Vasanth

    2014-01-01

    Full Text Available Follicular occlusion tetrad is a symptom complex consisting of four conditions having a similar pathophysiology. It includes Hidradenitis suppurativa, acne conglobata, dissecting cellulitis of the scalp and pilonidal sinus. The exact pathogenesis of this group of disease is unknown but evidence suggests that they share the same pathological process initiated by follicular occlusion in apocrine gland bearing areas. Though each of these conditions is commonly encountered singly, follicular occlusion tetrad as a symptom complex has been rarely reported in the literature.

  3. Distal arterial occlusive disease in diabetes is related to medial arterial calcification.

    Science.gov (United States)

    Chantelau, E; Lee, K M; Jungblut, R

    1997-01-01

    In diabetes mellitus, peripheral arterial occlusive disease predominantly affects the lower leg (tibial and peroneal vessel disease). Our study suggests that this feature is related to the presence of forefoot medial arterial calcification.

  4. Large-Scale Testing of Effects of Anti-Foam Agent on Gas Holdup in Process Vessels in the Hanford Waste Treatment Plant - 8280

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Alzheimer, James M.; Arm, Stuart T.; Guzman-Leong, Consuelo E.; Jagoda, Lynette K.; Stewart, Charles W.; Wells, Beric E.; Yokuda, Satoru T.

    2008-06-03

    The Hanford Waste Treatment Plant (WTP) will vitrify the radioactive wastes stored in underground tanks. These wastes generate and retain hydrogen and other flammable gases that create safety concerns for the vitrification process tanks in the WTP. An anti-foam agent (AFA) will be added to the WTP process streams. Prior testing in a bubble column and a small-scale impeller-mixed vessel indicated that gas holdup in a high-level waste chemical simulant with AFA was up to 10 times that in clay simulant without AFA. This raised a concern that major modifications to the WTP design or qualification of an alternative AFA might be required to satisfy plant safety criteria. However, because the mixing and gas generation mechanisms in the small-scale tests differed from those expected in WTP process vessels, additional tests were performed in a large-scale prototypic mixing system with in situ gas generation. This paper presents the results of this test program. The tests were conducted at Pacific Northwest National Laboratory in a ¼-scale model of the lag storage process vessel using pulse jet mixers and air spargers. Holdup and release of gas bubbles generated by hydrogen peroxide decomposition were evaluated in waste simulants containing an AFA over a range of Bingham yield stresses and gas gen geration rates. Results from the ¼-scale test stand showed that, contrary to the small-scale impeller-mixed tests, gas holdup in clay without AFA is comparable to that in the chemical waste simulant with AFA. The test stand, simulants, scaling and data-analysis methods, and results are described in relation to previous tests and anticipated WTP operating conditions.

  5. Removable partial denture occlusion.

    Science.gov (United States)

    Ivanhoe, John R; Plummer, Kevin D

    2004-07-01

    No single occlusal morphology, scheme, or material will successfully treat all patients. Many patients have been treated, both successfully and unsuccessfully, using widely varying theories of occlusion, choices of posterior tooth form, and restorative materials. Therefore, experience has demonstrated that there is no one righ r way to restore the occlusion of all patients. Partially edentulous patients have many and varied needs. Clinicians must understand the healthy physiologic gnathostomatic system and properly diagnose what is or may become pathologic. Henderson [3] stated that the occlusion of the successfully treated patient allows the masticating mechanism to carry out its physiologic functions while the temporomandibular joints, the neuromuscular mechanism, the teeth and their supporting structures remain in a good state of health. Skills in diagnosis and treatment planning are of utmost importance in treating these patients, for whom the clinician's goals are not only an esthetic and functional restoration but also a lasting harmonious state. Perhaps this was best state by DeVan [55] more than 60 years ago in his often-quoted objective. "The patient's fundamental need is the continued meticulous restoration of what is missing, since what is lost is in a sense irretrievably lost." Because it is clear that there is no one method, no one occlusal scheme, or one material that guarantees success for all patients, recommendations for consideration when establishing or reestablishing occlusal schemes have been presented. These recommendations must be used in conjunction with other diagnostic and technical skills.

  6. Occlusion of the circle of Willis. Diagnosis by 3D-time of flight MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Komatsumoto, Satoru; Ushioda, Takakazu; Nara, Masaharu [Ashikaga Red Cross Hospital, Tochigi (Japan)

    1996-08-01

    Magnetic resonance angiograms (MRA) were studied in 7 cases of occlusion of the circle of Willis. MRA successfully demonstrated the vascular obstructions and moyamoya vessels with a positive correlation to the angiographic findings. Leptomeningeal and transdural collateral vessels were also identified with MRA. As MRA is not invasive, it promises to become a valuable alternature to conventional angiography in the diagnosis of occlusion of the circle of Willis. (author)

  7. A non-contact technique for evaluation of elastic structures at large stand-off distances: applications to classification of fluids in steel vessels.

    Science.gov (United States)

    Kaduchak, G; Sinha, D N; Lizon, D C; Kelecher, M J

    2000-01-01

    A novel technique for non-contact evaluation of structures in air at large stand-off distances (on the order of several meters) has been developed. It utilizes a recently constructed air-coupled, parametric acoustic array to excite the resonance vibrations of elastic, fluid-filled vessels. The parametric array is advantageous for NDE applications in that it is capable of producing a much narrower beamwidth and broader bandwidth than typical devices that operate under linear acoustic principles. In the present experiments, the array operates at a carrier frequency of 217 kHz, and the sound field several meters from the source is described spectrally by the envelope of the drive voltage. An operating bandwidth of more than 25 kHz at a center frequency of 15 kHz is demonstrated. For the present application, the array is used to excite vibrations of fluid-filled, steel containers at stand-off distances of greater than 3 m. The vibratory response of a container is detected with a laser vibrometer in a monostatic configuration with the acoustic source. By analyzing the change in the response of the lowest order, antisymmetric Lamb wave as the interior fluid loading conditions of the container are changed, the fluid contained within the steel vessel is classified.

  8. Initial clinical experience with the Medtronic Micro Vascular Plug™ in transcatheter occlusion of PDAs in extremely premature infants.

    Science.gov (United States)

    Sathanandam, Shyam; Justino, Henri; Waller, B Rush; Radtke, Wolfgang; Qureshi, Athar M

    2017-05-01

    To describe the early multicenter, clinical experience with the Medtronic Micro Vascular Plug™ (MVP) for the occlusion of patent ductus arteriosus (PDA) in premature infants. The MVP is a large diameter plug that can be delivered through a microcatheter for occlusion of abnormal blood vessels. A Retrospective review of PDA embolization procedures performed in two centers using the MVP was performed. Fifteen premature infants underwent attempted PDA occlusion using the MVP. The gestational age and birth weight were 25.6 ± 2.5 weeks and 735 ± 251 g, respectively. The median weight and age at the time of the procedure were 1,210 g (700-3,500 g) and 4.5 weeks (2-12 weeks), respectively. Median procedure and fluoroscopy times were 45 and 6.5 min, respectively. The median radiation and contrast doses were 19.7 mGy and 2.4 mL/kg, respectively. Antegrade occlusion was successfully achieved in 13 patients 2 kg had arterial access and attempted retrograde occlusion; one of which was unsuccessful due to the PDA being short and wide. Complete closure was observed in 13 of 14 successful procedures (93%), with one patient having a small residual shunt that was not seen on follow-up. There were no complications related to the procedure or noted during follow-up (Median 11 months). The MVP is a new, large-diameter vascular embolization device that may be useful for the occlusion of PDA in extremely small, premature infants. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. The value of [{sup 18}F]FDG-PET in the diagnosis of large-vessel vasculitis and the assessment of activity and extent of disease

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Martin A.; Mueller-Brand, Jan; Nitzsche, Egbert U. [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Melzer, Ralph A.; Tyndall, Alan [University Hospital Basel, Division of Rheumatology (Switzerland); Schindler, Christian [University Hospital Basel, Institute of Social and Preventive Medicine (Switzerland)

    2005-06-01

    This study was performed to investigate the value of{sup 18}F-fluorodeoxyglucose positron emission tomography ([{sup 18}F]FDG-PET) in the diagnosis of large-vessel vasculitis and the assessment of activity and extent of disease. Twenty-six consecutive patients (21 females, 5 males; median age - years, range 17-86 years) with giant cell arteritis or Takayasu's arteritis were examined with [{sup 18}F]FDG-PET. Follow-up scans were performed in four patients. Twenty-six age- and gender-matched controls (21 females, 5 males; median age 71 years, range 17-86 years) were included. The severity of large-vessel [{sup 18}F]FDG uptake was visually graded using a four-point scale. C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) were measured and correlated with [{sup 18}F]FDG-PET results by logistic regression. [{sup 18}F]FDG-PET revealed pathological findings in 18 of 26 patients. Three scans were categorised as grade I, 12 as grade II and 3 as grade III arteritis. Visual grade was significantly correlated with both CRP and ESR levels (p=0.002 and 0.007 respectively; grade I: CRP 4.0 mg/l, ESR 6 mm/h; grade II: CRP 37 mg/l, ESR 46 mm/h; grade III: CRP 172 mg/l, ESR 90 mm/h). Overall sensitivity was 60% (95% CI 40.6-77.3%), specificity 99.8% (95% CI 89.1-100%), positive predictive value 99.7% (95% CI 77-100%), negative predictive value 67.9% (95% CI 49.8-80.9%) and accuracy 78.6% (95% CI 65.6-88.4%). In patients presenting with a CRP <12 mg/l or an ESR <12 mm/h, logistic regression revealed a sensitivity of less than 50%. In patients with high CRP/ESR levels, sensitivity was 95.5%/80.7%. [{sup 18}F]FDG-PET is highly effective in assessing the activity and the extent of large-vessel vasculitis. Visual grading was validated as representing the severity of inflammation. Its use is simple and provides high specificity, while high sensitivity is achieved by scanning in the state of active inflammation. (orig.)

  10. [Lingualized occlusion in the South African context].

    Science.gov (United States)

    Oberholzer, T G; Geerts, G A V M

    2002-01-01

    The search for the ideal artificial tooth arrangement that maximizes denture stability, comfort, aesthetics, and function has occupied the dental literature for many years and still continues to do so. Of the many occlusal schemes that have been presented to the dental profession, that of lingualized occlusion has emerged as one of the more popular. The popularity of lingualized occlusion stems from the simplicity and flexibility of the concept and from its wide application to clinical practice (Parr & Ivanhoe, 1996). The registration of a repeatable correct centric jaw relation is not always possible. We don't know whether the patient will use centric relation during normal function. It is therefore useful to provide the patient with some freedom of movement around centric. lingualized occlusion provides freedom in centric. For many dentists the arrangement of artificial denture teeth into balanced occlusion is difficult and time consuming. As a result this task is most often performed by the dental technician. In the South African countryside dental laboratories are often far away. If dentists perform the arrangement of the denture teeth, time and costs can be saved. The mounting of denture teeth in lingualized occlusion is simple and fast. This will motivate dentists to arrange denture teeth themselves, with obvious benefits for both the patient and the dentist. The School of Oral Health Sciences of the University of Stellenbosch teaches this concept to its undergraduate students in order to improve the prosthetic service to the large edentulous population of South Africa.

  11. Occlusion as a causative factor in TMD. Scientific basis to occlusal therapy.

    Science.gov (United States)

    Becker, I M

    1995-11-01

    There appears to be a pendulum swing toward large epidemiologic studies questioning the role of occlusion in dentistry. This article clearly demonstrates that significant scientific evidence exists on the side of occlusal causative factors. Clinicians need this current information to base practical decisions of treatment relative to both patients and those requiring restorative procedures. It further correctly clarifies that stress-related issues have an important role, along with other host-susceptibility altering factors.

  12. Clinical and angiographic comparison of asymptomatic occlusive cerebrovascular disease.

    Science.gov (United States)

    Gorelick, P B; Caplan, L R; Langenberg, P; Hier, D B; Pessin, M; Patel, D; Taber, J

    1988-06-01

    We compared clinical and arteriographic features in 106 patients with symptomatic unilateral carotid territory occlusive disease to determine the frequency and distribution of occlusive arterial lesions in asymptomatic vessels. Among black patients who were predominantly from Chicago, young, and female, there were fewer transient ischemic attacks and myocardial infarcts, less claudication, and more asymptomatic lesions of the supraclinoid internal carotid artery, anterior cerebral artery stem, and the middle cerebral artery stem. Among white patients predominantly from New England, elderly, and male, there was more frequent and severe occlusive asymptomatic disease at extracranial carotid and vertebral artery sites. Knowledge of the distribution of asymptomatic lesions will help guide evaluation and treatment strategies for patients with occlusive cerebrovascular disease.

  13. Celiac artery stenosis/occlusion treated by interventional radiology

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. On the Effect of Hull Girder Flexibility on the Vertical Wave Bending Moment for Ultra Large Container Vessels

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2012-01-01

    analysis is done using the First Order Reliability Method (FORM) supplemented with Monte Carlo simulations. Furthermore, strip-theory calculations are compared to model tests in regular waves of different wave lengths using a segmented, flexible model of the case-ship and good agreement is obtained...... for the 9,400 TEU container ship used as case-ship in the EU project TULCS (Tools for Ultra Large Container Ships). A non-linear time-domain strip theory is used for the hydrodynamic analysis of the vertical bending moment amidships in sagging and hogging conditions for a flexible and a rigid modelling...... of the ship. The theory takes into account non-linear radiation forces (memory effects) through the use of a set of higher order differential equations. The non-linear hydrostatic restoring forces and non-linear Froude-Krylov forces are determined accurately at the instantaneous position of the ship...

  15. Large eddy simulation of transitional flow in an idealized stenotic blood vessel: evaluation of subgrid scale models.

    Science.gov (United States)

    Pal, Abhro; Anupindi, Kameswararao; Delorme, Yann; Ghaisas, Niranjan; Shetty, Dinesh A; Frankel, Steven H

    2014-07-01

    In the present study, we performed large eddy simulation (LES) of axisymmetric, and 75% stenosed, eccentric arterial models with steady inflow conditions at a Reynolds number of 1000. The results obtained are compared with the direct numerical simulation (DNS) data (Varghese et al., 2007, "Direct Numerical Simulation of Stenotic Flows. Part 1. Steady Flow," J. Fluid Mech., 582, pp. 253-280). An inhouse code (WenoHemo) employing high-order numerical methods for spatial and temporal terms, along with a 2nd order accurate ghost point immersed boundary method (IBM) (Mark, and Vanwachem, 2008, "Derivation and Validation of a Novel Implicit Second-Order Accurate Immersed Boundary Method," J. Comput. Phys., 227(13), pp. 6660-6680) for enforcing boundary conditions on curved geometries is used for simulations. Three subgrid scale (SGS) models, namely, the classical Smagorinsky model (Smagorinsky, 1963, "General Circulation Experiments With the Primitive Equations," Mon. Weather Rev., 91(10), pp. 99-164), recently developed Vreman model (Vreman, 2004, "An Eddy-Viscosity Subgrid-Scale Model for Turbulent Shear Flow: Algebraic Theory and Applications," Phys. Fluids, 16(10), pp. 3670-3681), and the Sigma model (Nicoud et al., 2011, "Using Singular Values to Build a Subgrid-Scale Model for Large Eddy Simulations," Phys. Fluids, 23(8), 085106) are evaluated in the present study. Evaluation of SGS models suggests that the classical constant coefficient Smagorinsky model gives best agreement with the DNS data, whereas the Vreman and Sigma models predict an early transition to turbulence in the poststenotic region. Supplementary simulations are performed using Open source field operation and manipulation (OpenFOAM) ("OpenFOAM," http://www.openfoam.org/) solver and the results are inline with those obtained with WenoHemo.

  16. 大型高真空容器的气体负荷分析%Gas load analysis of large-scale high vacuum vessel

    Institute of Scientific and Technical Information of China (English)

    陆长胜; 于文泉; 黄金祥; 陆艳君; 岳向吉; 巴德纯

    2014-01-01

    With the improvement of science and technology , the development of some vacuum equipments goes toward large scale and high vacuum . Analysis shows that material degassing and gas leakage are the main gas load of large-scale high vacuum vessels . In order to enhance the technical level of large high-vacuum equipments , degassing and leakage should be given more attention in the design of chamber and sealing structure , leak detection design and technological analysis for manufacturing process .%随着科学技术的进步,某些用途的真空装置向大型化、高真空度的方向发展。分析表明材料出气和漏气是大型高真空容器的主要气体负荷,在容器及密封结构设计、检漏设计、制造工艺技术分析中应重点研究,以提高大型高真空装备的技术水平。

  17. Whole-body fluorodeoxyglucose positron emission tomography/computed tomography in patients with active polymyalgia rheumatica: evidence for distinctive bursitis and large-vessel vasculitis.

    Science.gov (United States)

    Yamashita, Hiroyuki; Kubota, Kazuo; Takahashi, Yuko; Minaminoto, Ryogo; Morooka, Miyako; Ito, Kimiteru; Kano, Toshikazu; Kaneko, Hiroshi; Takashima, Hiroshi; Mimoiri, Akio

    2012-09-01

    To investigate fluorodeoxyglucose (FDG) accumulation in large joints, bursas, and large vessels in patients with polymyalgia rheumatica (PMR) using 18-FDG positron emission tomography/computed tomography (PET/CT) and to differentiate PMR from similar diseases. Fourteen untreated patients with active PMR and 17 control patients with rheumatoid arthritis (n = 11) or other active rheumatic diseases (n = 6) underwent 18-FDG PET/CT. FDG uptake in large joints, bursas and vertebral spinous processes was evaluated by calculating maximum standardised uptake values and by visual scoring (scale 0-4). PET scan images were scored in seven vascular regions, and total vascular scores (range 0-21) were calculated. Polymyalgia rheumatica patients showed increased FDG uptake in ischial tuberosities, greater trochanters, and lumbar spinous processes. Positive results at two or more of these sites showed high sensitivity (85.7%) and specificity (88.2%) for the diagnosis of PMR, and shoulder or hip-joint involvement showed low disease specificity. High FDG accumulations were found in the aortas and subclavian arteries of two PMR patients who were asymptomatic for temporal arteritis and scanty synovium and perisynovium, based on FDG uptake. PET/CT images of the 12 PMR patients without apparent vascular involvement showed synovitis and/or perisynovitis. Fluorodeoxyglucose-PET/CT may be useful for the detection of PMR lesions, which are difficult to identify using other methods.

  18. Progression of Diabetic Capillary Occlusion: A Model.

    Directory of Open Access Journals (Sweden)

    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.

  19. Comparison of early (60 min) and delayed (180 min) acquisition of 18F-FDG PET/CT in large vessel vasculitis.

    Science.gov (United States)

    Martínez-Rodríguez, I; del Castillo-Matos, R; Quirce, R; Jiménez-Bonilla, J; de Arcocha-Torres, M; Ortega-Nava, F; Rubio-Vassallo, A; Martínez Amador, N; Ibáñez Bravo, S; Carril, J M

    2013-01-01

    To compare the contribution of the (18)F-FDG-PET/CT acquisition at 180 min and at 60 min in suspicion of large vessel vasculitis (LVV). A prospective study including 23 patients was performed. PET/CT was acquired at 60 and 180 min (early and delayed scan) after (18)F-FDG injection. A visual analysis was performed at the supra-aortic trunks (SAT), thoracic aorta (TA), abdominal aorta (AA), iliac arteries (IA) and femoral/tibioperoneal arteries (FTA). Intensity (0-3) and uptake pattern (diffuse/linear) were assessed in the 115 vascular regions. There was no FDG uptake in the early and delayed acquisition in 20/115 vascular regions (17.4%). Of the 95 regions (82.6%) showing FDG uptake at the early, delayed or both acquisitions, intensity did not change in the delayed acquisition in 46 and changed in 49. Of the 49 regions in which the intensity changed, it decreased in 36 and increased in 13 (TA:8, SAT:5). AA, IA and FTA intensity did not increase in any of the cases. Uptake pattern at the TA in the early acquisition was diffuse in 16 patients. In 7, it changed to linear and in 9 the uptake disappeared. The early pattern was linear in 7 patients and 6 of them showed increased intensity in the delayed acquisition and in 1 remained the same. The 180 min delayed FDG-PET/CT acquisition provides a more detailed visualized of the vessel wall, showing the washout of the blood pool activity. Therefore, it may contribute to a more accurate diagnosis of LVV. Copyright © 2012 Elsevier España, S.L. and SEMNIM. All rights reserved.

  20. [Experimental modeling of the blood vessels magnetic embolization].

    Science.gov (United States)

    Iacob, Gh; Ciochină, Al D; Bredeţean, O

    2005-01-01

    The embolization of blood vessels is used on a large scale: the method is applied in different diseases, in the ablation of organs, but especially in tumor necrosis. The embolization can be also magnetic, if the embolus is obtained through the deposit in the vessel of magnetic nano or microparticles in the presence of an external magnetic field. The objective of our study was the modeling of the magnetic embolization using amorphous magnetic microspheres that have strong magnetic properties and are biocompatible. Experimental tests were made in order to observe the building of the magnetic embolus inside a thin spiral tube and to determine the influence of some parameters on the efficiency of occlusions: the dimensions of magnetic microspheres (1-300 mm), the debit of the liquid (4.66 - 16.5 ml/min), the viscosity of the carrier liquid (1.007 - 7.34 cSt), the direction and the intensity of the external magnetic field (340 - 600 Gs), the shape of the tube and the linear length of the deposit (5 - 50 mm). Under pre-established experimental conditions the efficiencies of occlusions were between 67% and 100%.

  1. Management of acute ischemic stroke due to tandem occlusion: should endovascular recanalization of the extracranial or intracranial occlusive lesion be done first?

    Science.gov (United States)

    Rangel-Castilla, Leonardo; Rajah, Gary B; Shakir, Hakeem J; Shallwani, Hussain; Gandhi, Sirin; Davies, Jason M; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H

    2017-04-01

    OBJECTIVE Acute tandem occlusions of the cervical internal carotid artery and an intracranial large vessel present treatment challenges. Controversy exists regarding which lesion should be addressed first. The authors sought to evaluate the endovascular approach for revascularization of these lesions at Gates Vascular Institute. METHODS The authors performed a retrospective review of a prospectively maintained, single-institution database. They analyzed demographic, procedural, radiological, and clinical outcome data for patients who underwent endovascular treatment for tandem occlusions. A modified Rankin Scale (mRS) score ≤ 2 was defined as a favorable clinical outcome. RESULTS Forty-five patients were identified for inclusion in the study. The average age of these patients was 64 years; the mean National Institutes of Health Stroke Scale score at presentation was 14.4. Fifteen patients received intravenous thrombolysis before undergoing endovascular treatment. Thirty-seven (82%) of the 45 proximal cervical internal carotid artery occlusions were atherothrombotic in nature. Thirty-eight patients underwent a proximal-to-distal approach with carotid artery stenting first, followed by intracranial thrombectomy, whereas 7 patients underwent a distal-to-proximal approach (that is, intracranial thrombectomy was performed first). Thirty-seven (82%) procedures were completed with local anesthesia. For intracranial thrombectomy procedures, aspiration alone was used in 15 cases, stent retrieval alone was used in 5, and a combination of aspiration and stent-retriever thrombectomy was used in the remaining 25. The average time to revascularization was 81 minutes. Successful recanalization (thrombolysis in cerebral infarction Grade 2b/3) was achieved in 39 (87%) patients. Mean National Institutes of Health Stroke Scale scores were 9.3 immediately postprocedure (p acute carotid artery stenting and mechanical thrombectomy concurrently. Proximal-to-distal and aspiration

  2. A scoping review of the use of non-biologic disease modifying anti-rheumatic drugs in the management of large vessel vasculitis.

    Science.gov (United States)

    Misra, Durga Prasanna; Sharma, Aman; Kadhiravan, Tamilarasu; Negi, Vir Singh

    2017-02-01

    Takayasu's arteritis (TA) and Giant cell arteritis (GCA) comprise the large vessel vasculitides (LVV). Patients with LVV are treated with disease-modifying anti-rheumatic drugs (DMARDs), both conventional (cDMARDs) and biologic (bDMARDs). We undertook a scoping review to assess the effectiveness of cDMARDs in TA and GCA. We could identify 11 studies in TA and 18 studies in GCA. There were only 3 randomized controlled trials on methotrexate, one on hydroxychloroquine and two on cyclosporine in GCA, the others being case series (including all studies on TA). Most of these studies had small patient numbers (median 15 in TA and 27 in GCA). Outcome measures reported in different studies were heterogenous. Overall, methotrexate, leflunomide, azathioprine, mycophenolate mofetil and cyclophosphamide were effective in TA (low quality of evidence). Methotrexate (high quality of evidence), hydroxychloroquine and cyclosporine (moderate quality of evidence) appeared to be ineffective in GCA. Azathioprine (moderate quality of evidence), leflunomide, mycophenolate mofetil, cyclophosphamide and dapsone (low quality of evidence) were effective in GCA. There exists a paucity of high quality evidence to guide use of cDMARDs in TA and GCA. There is an unmet need to conduct large multi-centric randomized placebo-controlled trials to accurately assess the utility on cDMARDs in LVV.

  3. RETINAL BLOOD FLOW CORRELATES TO AQUEOUS VASCULAR ENDOTHELIAL GROWTH FACTOR IN CENTRAL RETINAL VEIN OCCLUSION.

    Science.gov (United States)

    Yamada, Yoshihisa; Suzuma, Kiyoshi; Matsumoto, Makiko; Tsuiki, Eiko; Fujikawa, Azusa; Harada, Takafumi; Kitaoka, Takashi

    2015-10-01

    As laser speckle flowgraphy can measure blood flow distribution in the ocular fundus, the authors analyzed the relationship between retinal blood flow and aqueous vascular endothelial growth factor (VEGF) concentration in central retinal vein occlusion. This prospective observational study examined 45 eyes of 45 patients with central retinal vein occlusion before treatment. Blood flow in large vessels around and at the optic disk, aqueous VEGF concentration, and arteriovenous passage time were examined. Blood flow was evaluated as mean blur rate by laser speckle flowgraphy. Fluorescein angiography found 20 ischemic and 25 nonischemic type eyes. Aqueous VEGF concentration in the ischemic type was significantly higher than that in the nonischemic type (P = 0.01). Arteriovenous passage time was significantly correlated to the logarithm of the aqueous VEGF concentration (P = 0.0001). Mean blur rate of the affected eye/mean blur rate of the unaffected eye of the ischemic type was significantly lower than the nonischemic type (P = 0.039). Additionally, mean blur rate was significantly correlated both to the logarithm of the aqueous VEGF concentration (P central retinal vein occlusion.

  4. Retinal vein occlusion

    Science.gov (United States)

    ... decrease the risk of retinal vein occlusion. These measures include: Eating a low-fat diet Getting regular exercise Maintaining an ideal weight Not smoking Aspirin or other blood thinners may help prevent blockages in the other eye. Controlling diabetes may ...

  5. Follicular occlusion triad

    Directory of Open Access Journals (Sweden)

    Mittal R

    1993-01-01

    Full Text Available One 40-year female was diagnosed as a case of follicular occlusion triad (FOT as she had hidradenitis suppurativa, acne conglobata and perifolliculitis capitis abscedens et suffodiens since 7 years. Partial improvement occurred within 20 days of treatment with co-trimoxazole and haematinics but relapse occurred after 5 days of stopping antibiotics.

  6. 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.

  7. Depicting Occlusion in Early Renaissance Art

    Science.gov (United States)

    Gillam, Barbara

    2011-01-01

    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.

  8. Large Pelagic Carcass Weights (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Swordfish have been a commercially caught species since the early 1800s. During this early stage of the fishery, harpoon was the principal gear and the fishing was...

  9. [Physiopathology of macular edema in central vein occlusion].

    Science.gov (United States)

    Stanca, Horia T; Manea, Georgiana

    2012-01-01

    Retinal Vein Occlusions are vascular diseases affecting the Central Retinal Vein and its branches causing decreased retinal drainage resulting in significant clinical and functional pathological changes. RVO determines the increase of vascular permeability, with edema and hemorrhage and development of collateral vessels in a few weeks. Among the serious consequences of venous occlusion is the installation of macular edema to which depends long-term visual prognosis. Macular Edema is the accumulation of intraretinal serous fluid in the macular area caused by the breakdown of blood-retinal barrier.

  10. Primary stenting as emergency therapy in acute basilar artery occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Spreer, Joachim; Arnold, Sebastian; Klisch, Joachim; Schumacher, Martin [Section of Neuroradiology, University Hospital Freiburg, Breisacher Strasse 64, 79106 Freiburg (Germany); Els, Thomas; Hetzel, Andreas; Huppertz, Hans-Juergen; Oehm, Eckhardt [Department of Neurology, University Hospital Freiburg, Freiburg (Germany)

    2002-09-01

    In three patients with acute occlusion of the basilar artery intra-arterial fibrinolysis resulted in only partial recanalization and revealed severe stenosis as the underlying cause. Application of micro-stents without previous dilatation resulted in vessel re-opening. Two patients had an excellent clinical outcome. One patient died 10 days after the stroke due to brainstem infarction. Emergency primary stent application may improve the outcome in acute basilar artery occlusion, if intra-arterial thrombolysis fails to re-establish a sufficient flow. (orig.)

  11. Bare-metal stenting of large coronary arteries in ST-elevation myocardial infarction is associated with low rates of target vessel revascularization.

    Science.gov (United States)

    Shugman, Ibrahim M; Hee, Leia; Mussap, Christian J; Diu, Patrick; Lo, Sidney; Hopkins, Andrew P; Nguyen, Phong; Taylor, David; Rajaratnam, Rohan; Leung, Dominic; Thomas, Liza; Juergens, Craig P; French, John K

    2013-04-01

    During percutaneous coronary intervention (PCI) performed in the emergent setting of ST-segment elevation myocardial infarction (STEMI), uncertainty about patients' ability to comply with 12 months dual antiplatelet therapy after drug-eluting stenting is common, and thus, selective bare-metal stent (BMS) deployment could be an attractive strategy if this achieved low target vessel revascularization (TVR) rates in large infarct-related arteries (IRAs) (≥3.5 mm). To evaluate this hypothesis, among 1,282 patients with STEMI who underwent PCI during their initial hospitalization, we studied 1,059 patients (83%) who received BMS, of whom 512 (48%) had large IRAs ≥3.5 mm in diameter, 333 (31%) had IRAs 3 to 3.49 mm, and 214 (20%) had IRAs <3 mm. At 1 year, TVR rate in patients with BMS was 5.8% (2.2% with large BMS [≥3.5 mm], 9.2% with BMS 3-3.49 mm [intermediate], and 9.0% with BMS <3.0 mm [small], P < .001). The rates of death/reinfarction among patients with large BMS compared with intermediate BMS or small BMS were lower (6.6% vs 11.7% vs 9.0%, P = .042). Among patients who received BMS, the independent predictors of TVR at 1 year were the following: vessel diameter <3.5 mm (odds ratio [OR] 4.39 [95% CI 2.24-8.60], P < .001), proximal left anterior descending coronary artery lesions (OR 1.89 [95% CI 1.08-3.31], P = .027), hypertension (OR 2.01 [95% CI 1.17-3.438], P = .011), and prior PCI (OR 3.46 [95% CI 1.21-9.85], P = .02). The predictors of death/myocardial infarction at 1 year were pre-PCI cardiogenic shock (OR 8.16 [95% CI 4.16-16.01], P < .001), age ≥65 years (OR 2.63 [95% CI 1.58-4.39], P < .001), left anterior descending coronary artery culprit lesions (OR 1.95 [95% CI 1.19-3.21], P = .008), female gender (OR 1.93 [95% CI 1.12-3.32], P = .019), and American College of Cardiology/American Heart Association lesion classes B2 and C (OR 2.17 [95% CI 1.10-4.27], P = .026). Bare-metal stent deployment in STEMI patients with IRAs ≥3.5 mm was associated

  12. Occlusion of Internal Carotid Artery in Kimura's Disease

    Directory of Open Access Journals (Sweden)

    Tomonori Tamaki

    2010-01-01

    Full Text Available We describe a unique case of Kimura's disease in which cerebral infarction was caused by occlusion of the right internal carotid artery. A 25-year-old man with Kimura's disease was admitted to our hospital because of left hemiparesis. Computed tomography and magnetic resonance imaging of the head showed infarction in the right frontal and temporal lobes. Cerebral angiography demonstrated right internal carotid artery occlusion affecting the C1 segment, with moyamoya-like collateral vessels arising from the right opthalamic artery. Kimura's disease is a chronic disease characterized by the clinical triad of slowly enlarging subcutaneous masses with lymphoid hyperplasia in the head and neck. It often occurs in young Asian men. In our patient, the pathogenesis of internal carotid artery occlusion was unknown. There have only been a few case reports in which occlusion of the internal carotid artery was associated with autoimmune disease, and no previous cases of internal carotid occlusion associated with Kimura's disease have been reported. We suspected that occlusion of this patient's internal carotid artery may be caused by the autoimmune mechanism that underlies Kimura's disease.

  13. Occlusive Peripheral Arterial Disease

    Science.gov (United States)

    ... off and blocks an artery downstream, if blood seeps into the lining of the artery causing a ... supply to heart muscle is adequate. Exposure to cold, which causes blood vessels to narrow (constrict) and ...

  14. Infrarenal Aortic Occlusion

    Science.gov (United States)

    Traverso, L. W.; Baker, J. D.; Dainko, E. A.; Machleder, H. I.

    1978-01-01

    Twenty-eight patients with total occlusion of the infrarenal aorta have been seen at the UCLA Hospitals in the past 11 years. Claudication was the presenting complaint in all but one patient, with one-third having ischemic rest pain. The average age of these patients was 54 years, and their histories revealed a surprising absence of myocardial infarction, stroke, or diabetes, although 40% had essential hypertension. Heavy tobacco use, however, was characteristic of the entire group. Arteriography proved valuable in identifying and characterizing the vascular abnormalities, but posed problems in technique and interpretation. Significant distal arterial disease was detected radiographically in only 21% of these patients. Operative correction of the aortic occlusion was performed on 26 patients, 18 by aortic bypass grafts and eight by aorto-iliac endarterectomy, with one early postoperative death. Although the thrombus extended to the renal artery origins in 77% of the cases, a well-designed technical approach did not require renal artery occlusion. Using serial creatinine determinations, one case of renal insufficiency was detected which was associated with prolonged postoperative hypotension. Although the extent of distal disease was more severe in those who underwent bypass, symptoms of claudication returned earlier and were more prominent in the endarterectomy group. This recurrence of systems was not favorably altered by sympathectomy performed concomitantly with the initial procedure. Even though this condition seems to pose difficult technical obstacles and has a poor prognosis, infrarenal aortic occlusion can be successfully treated by aortic bypass, with favorable long-term results, if particular attention is paid to elements of the preoperative evaluation and the intraoperative technical requirements peculiar to this relatively uncommon disease entity. ImagesFig. 1.Fig. 2.Fig. 3. PMID:646479

  15. Left atrial appendage occlusion

    Directory of Open Access Journals (Sweden)

    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.

  16. Subintimal TRAnscatheter Withdrawal (STRAW) of hematomas compressing the distal true lumen: a novel technique to facilitate distal reentry during recanalization of chronic total occlusion (CTO).

    Science.gov (United States)

    Smith, Elliot J; Di Mario, Carlo; Spratt, James C; Hanratty, Colm G; de Silva, Ranil; Lindsay, Alistair C; Grantham, J Aaron

    2015-01-01

    The development of a large hematoma impairing visualization of the distal true lumen is a recognized complication of antegrade recanalization of chronic total occlusions, often forcing the operator to abort the procedure or switch to a retrograde approach. We describe a novel technique utilizing an over-the-wire balloon inflated in the proximal occluded vessel to block inflow and allow aspiration of the blood from the subintimal space. This decompressed the true lumen, restored distal visualization, and allowed successful reentry using a dedicated technology. Utilization of this novel technique may rescue antegrade recanalization attempts complicated by large subintimal hematomas.

  17. Dental occlusion: modern concepts and their application in implant prosthodontics.

    Science.gov (United States)

    Carlsson, Gunnar E

    2009-01-01

    The aim of this article was to review the literature on various aspects of occlusion related to implant prosthodontics, using PubMed and the Cochrane library. Even if the number of studies on implants and prosthodontics is very large, no randomized controlled trials or Cochrane reviews were found on the possible influence of occlusal design or characteristics of occlusion on treatment outcome. Therefore, studies and articles of a lower evidence level were accepted as the main part of the review. The widely spread opinion that implants are superior to natural teeth was refuted by two recent consensus conferences, which concluded that the long-term outcome of implant restorations is not better than that of natural teeth. No controlled studies on the optimal features of a harmonious natural and/or restored occlusion, including implant prostheses, were found. Nor was there any evidence that more sophisticated methods in jaw registration, e.g., using face-bows and adjustable articulators, compared with simpler methods, will yield better clinical prosthodontic results. This article discusses, among other things, concepts of occlusion of implant-supported restorations, occlusal material, cantilevers, and occlusal risk factors. Within the limitations of the review, it was concluded that many factors can influence implant failure and peri-implant bone loss but that little is known of the relative importance of such factors. Most probably, however, occlusal factors and details of occlusion are in general of minor importance for the outcome of implant restorations. Occlusion can be managed successfully by using simple methods for jaw registration and different occlusal concepts.

  18. An alternative treatment of occlusal wear: Cast metal occlusal surface

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar

    2012-01-01

    Full Text Available Acrylic resin denture teeth often exhibit rapid occlusal wear, which may lead to decrease in the chewing efficiency, loss of vertical dimension of occlusion, denture instability, temporomandibular joint disturbances, etc. There are various treatment options available like, use of highly cross linked acrylic teeth, amalgam or metal inserts on occlusal surface, use of composite, gold or metal occlusal surface, etc. Several articles have described methods to construct gold and metal occlusal surfaces, however, these methods are time-consuming, expensive and requires many cumbersome steps. These methods also requires the patient to be without the prosthesis for the time during which the laboratory procedures are performed. This article presents a quick, simple and relatively inexpensive procedure for construction of metal occlusal surfaces on complete dentures.

  19. 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.

  20. Embolization with temporary balloon occlusion of the internal carotid or vertebral arteries

    Energy Technology Data Exchange (ETDEWEB)

    Theron, J.; Cosgrove, R.; Melanson, D.; Ethier, R.

    1986-05-01

    Functional vascular anastomoses at the base of the brain allow for temporary occlusion of the carotid or vertebral arteries. Six embolizations with temporary balloon occlusion of the internal carotid or vertebral artery are reported. Polyvinyl alcohol was the embolic material in all cases and all procedures were performed using digital angiography. The size of the embolic particles and the positioning of the balloon related to the branches of the occluded vessel is discussed.

  1. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  2. [The development of the system of blood flow block by using magnetic compression abdominal large vascular].

    Science.gov (United States)

    Yan, Xiaopeng; Lv, Yi; Ma, Feng; Ma, Jia; Wang, Haohua; Wang, Shanpei; Li, Dichen; Liu, Yaxiong; Jia, Shenli; Shi, Zongqian; Luo, Ruixue

    2014-03-01

    A new system of blood flow block for control of bleeding in abdominal operation is composed of an abdominal magnetic blocking unit, an abdominal external electromagnet unit and other non-magnetic operation instrument. The abdominal external electromagnetic unit is placed in advance in the operation bed. The abdominal magnetic blocking unit can be placed directly on the ventral of the large vessels when need to blocking the abdominal large vessels during the operation. According to the non-contact suction characteristics of magnetic materials, the two magnetic units will attract each other and compression the vessels. Using this system for vascular occlusion does not need clear exposure and without separating vessel. There is the advantage of rapid, accurate and reliable for the system.

  3. [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.

  4. Comparative analysis of ECGs in navy personnel onboard large and small vessels during prolonged deployment at sea%海军护航不同舰艇官兵的心电图对比分析

    Institute of Scientific and Technical Information of China (English)

    杨翅; 蒋建华; 柳兵; 陈文; 彭焕亭

    2015-01-01

    目的:观察海军大、小不同类型舰艇亚丁湾护航返回官兵心电图特点。方法对赴亚丁湾海域护航返回的某补给舰(简称大舰组)140名官兵、某护卫舰(简称小舰组)79名官兵,分别在2艘舰艇返回靠泊的当天,行常规体表12导联心电图检测,比较心电图异常及心率、各波间期的变化情况。结果小舰组官兵室性早搏发生率高于大舰组官兵,差异有统计学意义(P<0.05);心率、左心室高电压、ST-T改变、早期复极、间歇性Ⅰ度或Ⅱ度Ⅰ型房室传导阻滞及各波形的间期差异均无统计学意义(P>0.05)。结论小舰官兵心律失常发生率高于大舰官兵,可能与小舰官兵自主神经功能失衡程度高,造成交感神经兴奋性增高有关。%Objective To observe the change features of ECG in navy personnel onboard large and small vessels after they re -turn from prolonged deployment to the Gulf of Aden .Methods One hundred and forty navy personnel onboard the auxiliary ship ( sim-ply designated as the large vessel ) and 79 people onboard the escort ( simply called the small vessel ) respectively received routine body surface 12-lead ECG detection , on the day they returned to the homeport , following prolonged deployment at sea .Abnormality in ECG and changes in heart rate and wave intervals were compared between the 2 ship crews.Results The incidence of premature ventricular contraction for the afloat personnel onboard the small vessel was higher than that for those onboard the large vessel (P0.05).Conclusion The incidence of arrhythmia for the afloat personnel onboard small vessel was evidently higher than that for the afloat personnel onboard the large ves -sel, which might be related with autonomic nervous system dysfunction and increased sympathetic nerve excitability .

  5. 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.

  6. 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.

  7. 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.

  8. Dissolution vessel

    Energy Technology Data Exchange (ETDEWEB)

    Natsume, Tomohiro; Fujioka, Tsunaaki

    1998-05-22

    A basket for containing sheared fuel pieces of spent fuel assemblies in a dissolving vessel main body has many apertures for keeping the concentration of a dissolving liquid at the inner side and the outer side of the basket uniformly. Secured neutron absorbers such as boron stainless and hafnium are appended to one or both surfaces of the basket. Partitioning members are disposed in the basket, and the partitioning members are formed in a lattice-like shape. The partitioning members are also made of secured neutron absorbers such as boron stainless and hafnium. The inside dimension of each division (lattice distance) is determined to about 15cm. Then, it is no more necessary to add soluble neutron absorbers such as gadolinium nitrate to a dissolution solution such as nitric acid thereby enabling to reduce the amount of radioactive wastes. (I.N.)

  9. Tracking people through partial occlusions

    Institute of Scientific and Technical Information of China (English)

    LU Jian-guo; CAI An-ni

    2009-01-01

    This article presents a novel people-tracking approach to cope with partial occlusions caused by scene objects. Instead of predicting when and where the occlusions will occur, a part-based model is used to model the pixel distribution of the target body under occlusion. The subdivided patches corresponding to a template image will be tracked independently using Markov chain Monte Carlo (MCMC) method. A set of voting-based rules is established for the patch-tracking result to verify if the target is indeed located at the estimated position. Experiments show the effectiveness of the proposed method.

  10. Society of Vascular and Interventional Neurology (SVIN) Stroke Interventional Laboratory Consensus (SILC) Criteria: A 7M Management Approach to Developing a Stroke Interventional Laboratory in the Era of Stroke Thrombectomy for Large Vessel Occlusions.

    Science.gov (United States)

    Shams, Tanzila; Zaidat, Osama; Yavagal, Dileep; Xavier, Andrew; Jovin, Tudor; Janardhan, Vallabh

    2016-06-01

    Brain attack care is rapidly evolving with cutting-edge stroke interventions similar to the growth of heart attack care with cardiac interventions in the last two decades. As the field of stroke intervention is growing exponentially globally, there is clearly an unmet need to standardize stroke interventional laboratories for safe, effective, and timely stroke care. Towards this goal, the Society of Vascular and Interventional Neurology (SVIN) Writing Committee has developed the Stroke Interventional Laboratory Consensus (SILC) criteria using a 7M management approach for the development and standardization of each stroke interventional laboratory within stroke centers. The SILC criteria include: (1) manpower: personnel including roles of medical and administrative directors, attending physicians, fellows, physician extenders, and all the key stakeholders in the stroke chain of survival; (2) machines: resources needed in terms of physical facilities, and angiography equipment; (3) materials: medical device inventory, medications, and angiography supplies; (4) methods: standardized protocols for stroke workflow optimization; (5) metrics (volume): existing credentialing criteria for facilities and stroke interventionalists; (6) metrics (quality): benchmarks for quality assurance; (7) metrics (safety): radiation and procedural safety practices.

  11. Vascular Occlusions in Grapevines with Pierce’s Disease Make Disease Symptom Development Worse1[OA

    Science.gov (United States)

    Sun, Qiang; Sun, Yuliang; Walker, M. Andrew; Labavitch, John M.

    2013-01-01

    Vascular occlusions are common structural modifications made by many plant species in response to pathogen infection. However, the functional role(s) of occlusions in host plant disease resistance/susceptibility remains controversial. This study focuses on vascular occlusions that form in stem secondary xylem of grapevines (Vitis vinifera) infected with Pierce’s disease (PD) and the impact of occlusions on the hosts’ water transport and the systemic spread of the causal bacterium Xylella fastidiosa in infected vines. Tyloses are the predominant type of occlusion that forms in grapevine genotypes with differing PD resistances. Tyloses form throughout PD-susceptible grapevines with over 60% of the vessels in transverse sections of all examined internodes becoming fully blocked. By contrast, tylose development was mainly limited to a few internodes close to the point of inoculation in PD-resistant grapevines, impacting only 20% or less of the vessels. The extensive vessel blockage in PD-susceptible grapevines was correlated to a greater than 90% decrease in stem hydraulic conductivity, compared with an approximately 30% reduction in the stems of PD-resistant vines. Despite the systemic spread of X. fastidiosa in PD-susceptible grapevines, the pathogen colonized only 15% or less of the vessels in any internode and occurred in relatively small numbers, amounts much too small to directly block the vessels. Therefore, we concluded that the extensive formation of vascular occlusions in PD-susceptible grapevines does not prevent the pathogen’s systemic spread in them, but may significantly suppress the vines’ water conduction, contributing to PD symptom development and the vines’ eventual death. PMID:23292789

  12. Vascular occlusions in grapevines with Pierce's disease make disease symptom development worse.

    Science.gov (United States)

    Sun, Qiang; Sun, Yuliang; Walker, M Andrew; Labavitch, John M

    2013-03-01

    Vascular occlusions are common structural modifications made by many plant species in response to pathogen infection. However, the functional role(s) of occlusions in host plant disease resistance/susceptibility remains controversial. This study focuses on vascular occlusions that form in stem secondary xylem of grapevines (Vitis vinifera) infected with Pierce's disease (PD) and the impact of occlusions on the hosts' water transport and the systemic spread of the causal bacterium Xylella fastidiosa in infected vines. Tyloses are the predominant type of occlusion that forms in grapevine genotypes with differing PD resistances. Tyloses form throughout PD-susceptible grapevines with over 60% of the vessels in transverse sections of all examined internodes becoming fully blocked. By contrast, tylose development was mainly limited to a few internodes close to the point of inoculation in PD-resistant grapevines, impacting only 20% or less of the vessels. The extensive vessel blockage in PD-susceptible grapevines was correlated to a greater than 90% decrease in stem hydraulic conductivity, compared with an approximately 30% reduction in the stems of PD-resistant vines. Despite the systemic spread of X. fastidiosa in PD-susceptible grapevines, the pathogen colonized only 15% or less of the vessels in any internode and occurred in relatively small numbers, amounts much too small to directly block the vessels. Therefore, we concluded that the extensive formation of vascular occlusions in PD-susceptible grapevines does not prevent the pathogen's systemic spread in them, but may significantly suppress the vines' water conduction, contributing to PD symptom development and the vines' eventual death.

  13. Occlusion, transparency, and lightness.

    Science.gov (United States)

    Albert, Marc K

    2007-11-01

    The lightness of a visual surface is its perceived achromatic reflectance [Adelson, E. H., (2000). Lightness perception and lightness illusions. In M. Gazzaniga (Ed.), The new cognitive neuroscience (2nd ed.) (pp. 339-351) Berlin: Springer; Gilchrist, A. (1999). Lightness perception. In R. W. F. Keil (Ed.), MIT encyclopedia of cognitive science (pp. 471-472). Cambridge: MIT press]. Lightness ranges from black, through various shades of grey, up to white. Anderson and Winawer [Anderson, B., Winawer, J. (2005). Image segmentation and lightness perception. Nature, 434, 79-83] suggested that perceptual decomposition of image luminance into multiple sources in different layers (e.g., perceptual transparency) is critical to the their lightness illusions. However, I show that simple perceptual occlusion evoked by T-junctions will work as well, suggesting that perceptual scission of luminance into multiple layers is unnecessary for such effects. I argue that the lightness illusions presented by Anderson and Winawer involve fundamentally different mechanisms than previously studied lightness illusions, including those involving perceptual transparency.

  14. 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

  15. A comparison of Selective Aortic Arch Perfusion and Resuscitative Endovascular Balloon Occlusion of the Aorta for the management of hemorrhage-induced traumatic cardiac arrest: A translational model in large swine.

    Directory of Open Access Journals (Sweden)

    Ed B G Barnard

    2017-07-01

    Full Text Available Survival rates remain low after hemorrhage-induced traumatic cardiac arrest (TCA. Noncompressible torso hemorrhage (NCTH is a major cause of potentially survivable trauma death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA at the thoracic aorta (Zone 1 can limit subdiaphragmatic blood loss and allow for IV fluid resuscitation when intrinsic cardiac activity is still present. Selective Aortic Arch Perfusion (SAAP combines thoracic aortic balloon hemorrhage control with intra-aortic oxygenated perfusion to achieve return of spontaneous circulation (ROSC when cardiac arrest has occurred.Male Yorkshire Landrace cross swine (80.0 ± 6.0 kg underwent anesthesia, instrumentation for monitoring, and splenectomy. TCA was induced by laparoscopic liver lobe resection combined with arterial catheter blood withdrawal to achieve a sustained systolic blood pressure <10 mmHg, cardiac arrest. After 3 min of arrest, swine were allocated to one of three interventions: (1 REBOA plus 4 units of IV fresh whole blood (FWB, (2 SAAP with oxygenated lactated Ringer's (LR, 1,600 mL/2 min, or (3 SAAP with oxygenated FWB 1,600 mL/2 min. Primary endpoint was survival to the end of 60 min of resuscitation, a simulated prehospital phase. Thirty animals were allocated to 3 groups (10 per group-5 protocol exclusions resulted in a total of 35 animals being used. Baseline measurements and time to cardiac arrest were not different amongst groups. ROSC was achieved in 0/10 (0%, 95% CI 0.00-30.9 REBOA, 6/10 (60%, 95% CI 26.2-87.8 SAAP-LR and 10/10 (100%, 95% CI 69.2-100.0 SAAP-FWB animals, p < 0.001. Survival to end of simulated 60-minute prehospital resuscitation was 0/10 (0%, 95% CI 0.00-30.9 for REBOA, 1/10 (10%, 95% CI 0.25-44.5 for SAAP-LR and 9/10 (90%, 95% CI 55.5-99.7 for SAAP-FWB, p < 0.001. Total FWB infusion volume was similar for REBOA (2,452 ± 0 mL and SAAP-FWB (2,250 ± 594 mL. This study was undertaken in laboratory conditions, and as such may have

  16. Clinical issues in occlusion - Part II.

    Science.gov (United States)

    Patel, Mahul; Alani, Aws

    2015-12-01

    Occlusal diagnosis plays an important role in the planning and subsequent delivery of predictable functional and aesthetic restorations and prostheses. Once an occlusal problem is identified there are a number of techniques and materials that can be utilised to record occlusal relationships, subsequently analyse them and incorporate information obtained into the delivery of tooth restoration or replacement. This paper discusses the clinical and technical aspects of occlusal examination and analysis outlining contemporary and traditional techniques in their utilisation. Aspects of occlusal examination will be revisited; the identification and recording of centric occlusion as well as subsequent articulation will be discussed. The requirement for occlusal splint provision will also be discussed and illustrated.

  17. Central retinal vein occlusion concomitant with dengue fever.

    Science.gov (United States)

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengue fever. A 41 year old Malay female was admitted to medical ward and diagnosed to have "dengue fever with warning signs". On the day of admission she noted sudden onset of right eye blurring of vision. She presented to our clinic 1 week later. Ocular examination revealed right eye visual acuity of <20/1000 and ischaemic CRVO with macular edema. She had no other risk factors to develop retinal vein occlusion. She progressively developed proliferative retinopathy and received multiple laser therapy. There was no anterior segment neovascularization. However, her vision improved to only 20/400 despite of resolution of macular edema and new vessels elsewhere. Dengue virus infection is known to cause thrombocytopenia which can result in hemorrhagic events. It can also cause procoagulant state which can result in thrombotic events secondary to immune reaction. Awareness among treating physicians of such ocular complication which can result in significant morbidity for patient is necessary.

  18. Occlusion-free Blood Flow Animation with Wall Thickness Visualization.

    Science.gov (United States)

    Lawonn, Kai; Glaßer, Sylvia; Vilanova, Anna; Preim, Bernhard; Isenberg, Tobias

    2016-01-01

    We present the first visualization tool that combines pathlines from blood flow and wall thickness information. Our method uses illustrative techniques to provide occlusion-free visualization of the flow. We thus offer medical researchers an effective visual analysis tool for aneurysm treatment risk assessment. Such aneurysms bear a high risk of rupture and significant treatment-related risks. Therefore, to get a fully informed decision it is essential to both investigate the vessel morphology and the hemodynamic data. Ongoing research emphasizes the importance of analyzing the wall thickness in risk assessment. Our combination of blood flow visualization and wall thickness representation is a significant improvement for the exploration and analysis of aneurysms. As all presented information is spatially intertwined, occlusion problems occur. We solve these occlusion problems by dynamic cutaway surfaces. We combine this approach with a glyph-based blood flow representation and a visual mapping of wall thickness onto the vessel surface. We developed a GPU-based implementation of our visualizations which facilitates wall thickness analysis through real-time rendering and flexible interactive data exploration mechanisms. We designed our techniques in collaboration with domain experts, and we provide details about the evaluation of the technique and tool.

  19. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  20. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit from...

  1. Non-occlusive mesenteric ischemia: etiology, diagnosis, and interventional therapy

    Energy Technology Data Exchange (ETDEWEB)

    Trompeter, Markus; Brazda, Thurid; Remy, Christopher T.; Reimer, Peter [Department of Radiology, Staedtisches Klinikum Karlsruhe (Germany); Vestring, Thomas [Department of Radiology, Diakonie-Krankenhaus Rotenburg/Wuemme, Goettingen (Germany)

    2002-05-01

    Non-occlusive mesenteric ischemia (NOMI) compromises all forms of mesenteric ischemia with patent mesenteric arteries. It generally affects patients over 50 years of age suffering from myocardial infarction, congestive heart failure, aortic insufficiency, renal or hepatic disease and patients following cardiac surgery. Non-occlusive disease accounts for 20-30% of all cases of acute mesenteric ischemia with a mortality rate of the order of 50%. Acute abdominal pain may be the only early presenting symptom of mesenteric ischemia. Non-invasive imaging modalities, such as CT, MRI, and ultrasound, are able to evaluate the aorta and the origins of splanchnic arteries. Despite the technical evolution of those methods, selective angiography of mesenteric arteries is still the gold standard in diagnosing peripheral splanchnic vessel disease. In early non-occlusive mesenteric ischemia, as opposed to occlusive disease, there is no surgical therapy. It is known that mesenteric vasospasm persists even after correction of the precipitating event. Vasospasm frequently responds to direct intra-arterial vasodilator therapy, which is the only treatment that has been shown to be effective. (orig.)

  2. Prior blunt chest trauma may be a cause of single vessel coronary disease; hypothesis and review

    DEFF Research Database (Denmark)

    Bartels, Mette Damkjær; Nielsen, PE; Sleight, P

    2006-01-01

    old, and only 2.5% more than 60 years old. The most common trauma was a road traffic accident, and the LAD was the vessel most often affected. Angiography revealed 12 cases with completely normal vessels, which might be due to spasm or recanalisation; 31 cases showed occlusion but no atherosclerosis...

  3. Differentiation of total occlusion and high-grade stenosis in coronary CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Erffa, J. von; Ropers, D.; Pflederer, T.; Schmid, M.; Marwan, M.; Daniel, W.G.; Achenbach, S. [University of Erlangen, Department of Internal Medicine 2, Erlangen (Germany)

    2008-12-15

    In coronary CT angiography (CTA), both high-grade stenoses and total occlusions of a coronary artery may appear as a complete interruption of the contrast-enhanced lumen. Parameters to differentiate between occlusions and stenoses have not been systematically assessed. We evaluated 40 consecutive patients with a lesion demonstrating complete interruption of the contrast-enhanced lumen in coronary CTA and in whom invasive coronary angiography was available. Length of the vessel segment without luminal contrast enhancement; luminal enhancement proximal, in and distal to the lesion; degree of coronary remodelling; and the degree of lesion calcification were assessed by a blinded observer unaware of the invasive angiogram. Mean length of complete occlusions (n = 20; range 4-54 mm; mean 16.6 {+-} 3.5 mm) was significantly longer than for high-grade stenoses (n = 20; 2-8 mm; mean 4.6 {+-} 1.7 mm, p < 0.001). A lesion length {>=} 9 mm was 100% specific and 70% sensitive for an occlusion. No significant differences were found for vessel enhancement in or distal to the lesion, remodelling index or degree of calcification. Lesion length is the only parameter that may differentiate complete occlusions and high-grade stenoses in coronary CTA. For lesions {>=} 9 mm, an occlusion is very likely. (orig.)

  4. Short- and long-term outcomes of single bare metal stent versus drug eluting stent in nondiabetic patients with a simple de novo lesion in the middle and large vessel

    Directory of Open Access Journals (Sweden)

    Li Jian-jun

    2008-08-01

    Full Text Available Abstract Objective This study was aimed to investigate the short- and long-term outcomes of percutaneous coronary intervention (PCI between single bare metal stent (BMS and single drug eluting stent (DES in nondiabetic patients with a simple de novo lesion in the middle and large vessel. Methods Two hundred and thirty-five consecutive patients with a simple de novo lesion in the middle and large vessel were treated with BMS or DES in our hospital from Apr. 2004 to Dec. 2004. The inclusion criteria: a simple de novo lesion in the middle and large vessel, stent diameter ≥ 3.0 mm, stent length ≤ 18 mm, the exclusion criteria: diabetes mellitus, left main trunk disease and left ventricular ejection fraction ≤ 30%. Of them, there were 150 patients in BMS group and 85 patients in DES group, and the rates of lost to follow up were 6.7% and 1.2% respectively. Results BMS group had lower hypercholesteremia rate (22.0% vs 38.8% and higher proportion of TIMI grade 0 (12% vs 1.2% than DES group (all P 0.05. No difference was found in TLR (1.3% vs 1.2%, P = 1.00 and recurrent myocardial infarction (Re-MI (0% vs 1.2%, P = 0.36, cardiac death (0.7% vs 1.2%, P = 1.00 between 1- and 3-year. So were TLR (6.0% vs 5.9%, P = 0.97, Re-MI (0% vs 2.4%, P = 0.06, cardiac death (2.0% vs 3.5%, P = 0.48 and major adverse cardiac events (MACE, 8.7% vs 10.6%, P = 0.63, cardiac death-free cumulative survival (98.7% vs 97.7%, P = 0.56, TLR-free cumulative survival (94.0% vs 94.1%, P = 0.98 and Re-MI-free cumulative survival (100% vs 97.7%, P = 0.06 at 3-year follow-up. Conclusion The single BMS has similar efficacy and safety to single DES in nondiabetic patients with a simple de novo lesion in the middle and large vessel at short- and long-term follow-up.

  5. Occlusion-Aware View Interpolation

    Directory of Open Access Journals (Sweden)

    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.

  6. Occlusion-Aware View Interpolation

    Directory of Open Access Journals (Sweden)

    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.

  7. Endograft Limb Occlusion in EVAR

    DEFF Research Database (Denmark)

    Taudorf, M; Jensen, L P; Vogt, K C

    2014-01-01

    OBJECTIVE: To assess the incidence and outcome of graft limb occlusions after endovascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA) in a high volume single centre. To quantify iliac artery tortuosity in patients with AAA and correlate this with limb occlusion. DESIGN: Data were...... collected consecutively and prospectively, and analyzed retrospectively. MATERIALS: Patients treated with Zenith bifurcated stent grafts from January 2000 to December 2010 at a tertiary referral vascular unit were analyzed. Routine regular office follow-up with computed tomography angiography (CTA) and......, subsequently, duplex ultrasound imaging was performed. Patients with limb occlusions were identified. For each index patient, two controls were obtained, one immediately preceding and one following the index patient in the consecutive cohort of EVAR patients. METHODS: Demographics and CTA data on limb graft...

  8. A Thermofluid Analysis of the Magnetic Nanoparticles Enhanced Heating Effects in Tissues Embedded with Large Blood Vessel during Magnetic Fluid Hyperthermia

    Directory of Open Access Journals (Sweden)

    Koustov Adhikary

    2016-01-01

    Full Text Available The thermal effect developed due to the heating of magnetic nanoparticles (MNPs in presence of external magnetic field can be precisely controlled by the proper selection of magnetic absorption properties of the MNPs. The present paper deals with the numerical simulation of temperature field developed within or outside the tumor, in the presence of an external alternating magnetic field, using a thermofluidic model developed using ANSYS FLUENT®. A three-layer nonuniform tissue structure with one or two blood vessels surrounding the tumor is considered for the present simulation. The results obtained clearly suggest that the volumetric distribution pattern of MNPs within the tumor has a strong influence on the temperature field developed. The linear pattern of volumetric distribution has a strong effect over the two other types of distribution considered herein. Various other important factors like external magnetic field intensity, frequency, vascular congestion, types of MNP material, and so forth are considered to find the influence on the temperature within the tumor. Results show that proper selection of these parameters has a strong influence on the desired therapeutic temperature range and thus it is of utmost importance from the efficacy point of view of magnetic fluid hyperthermia (MFH.

  9. A Novel Nitinol Spherical Occlusion Device for Liver Cancer

    Directory of Open Access Journals (Sweden)

    Hao-Ming Hsiao

    2016-01-01

    Full Text Available Liver cancer or hepatic cancer is a cancer that originates in the liver. It is formed from either the liver itself or from structures within the liver, including blood vessels or the bile duct. Liver cancer can be a life-threatening condition, but it may be cured if found early. Hepatic artery embolization is one of the treatment options involving the injection of substances to reduce the blood flow to cancer cells in the livers of patients with tumors that cannot be removed by surgery; however, this treatment has some limitations. In this paper, we propose a novel nitinol “spherical occlusion device” concept, the first of its kind in the world. Our proposed spherical occlusion device is able to reduce the blood flow to cancer cells by deploying it in the upstream hepatic artery supplying blood to the liver. Moreover, it could carry multiple chemotherapy or radioactive drugs for delivery directly to the target site. Nitinol alloy was chosen as the device material due to its excellent super-elastic property. Computational models were developed to predict the mechanical response of the device during manufacturing and deployment procedures, as well as its hemodynamic behavior. Simulation results showed that the presence of the spherical occlusion device with 14%–27% metal density deployed at the upstream location of the right hepatic artery had significant occlusion effects, with the average blood flow rate cut down by 30%–50%. A pulsed fiber laser and a series of expansions and heat treatments were developed to make the first prototype of the spherical occlusion device for the demonstration of our novel concept.

  10. Surgical treatment of brachiocephalic vessel involvement in Takayasu's arteritis

    Institute of Scientific and Technical Information of China (English)

    WU Xin; DUAN Hong-yong; GU Yong-quan; LI Jian-xin; CHEN Bing; WANG Zhong-gao; ZHANG Jian

    2010-01-01

    Background Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease that affects large and medium size arteries. The brachiocephalic trunk is the most frequently involved site in TA, and multi-vessel lesions are common. Surgical treatment includes vessel reconstruction surgery and percutaneous transluminal angioplasty (PTA). Herein, we report our preliminary experience with surgical treatment of cerebral ischemia caused by cervical arterial lesions due to TA.Methods From January 2000 to December 2007, 38 patients with cerebral ischemia caused by cervical arterial occlusive lesions due to TA were treated surgically. There were three males and 35 females, with an age range of 15-42 years (mean 26.5 years). All patients had operative repairs undertaken. Twenty eight patients received bypass operation and 10 patients received percutaneous transluminal angioplasty. One case with coronary stenosis received coronary artery bypass simultaneously. Patients were followed up for 11 months to eight years.Results There were no peri-operative deaths in cerebrovascular reconstruction patients. Symptoms of cerebral ischemia were improved or cured in 25 of 38 patients. There was a low incidence of cerebral reperfusion syndrome. Two patients died at five and seven years after surgery due to heart failure. Another 8 patients (20%) required further surgery for stenosis (5 patients) or anastomotic aneurysms (3 patients). Percutaneous transluminal angioplasty was performed successfully for treatment of aortic and renal lesions. Repeated angioplasty for revascularization was performed in six PTA cases with restenosis after 5-24 months.Conclusions When cerebral perfusion has potential to be affected by TA, a definitive corrective procedure is advised when the patient is relatively stable. Although the recurrence rate is very high, percutaneous transluminal angioplasty is the first choice procedure. Bypass operation is optimal for brachiocephalic-vessel involvement in TA

  11. Occlusion Effect of a Long-pulsed 532nm Laser on Veins

    Institute of Scientific and Technical Information of China (English)

    ZHANGLai-ming; YANGGui-long; LIDian-jun; LUQi-peng; GUHua-dong; ZHULin-lin; ZHAOZhen-wu; LIXin; WANGJing-ping; TANGYu-guo; GUOJin

    2005-01-01

    Laser treatment represents an attractive option to other methods of vessel diseases especially varicose veins. A long pulse (30-50ms) 532nm laser was used in our experiments, with the pulse duration matching the thermal relaxation time of the vessels and the green laser matching the absorption spectrum peak of the blood.Laser irradiates nude vein vessels directly or exterior skin to finish operation faster and to acquire the practical data for upper enteron varicose vein treatment in several animal experiments performed in vivo. The 5Jenergy pulse allows us to finely occlude rabbit or dog's vein vessels up to 2 mm in diameter when irradiating them off external skin. Blood vessels are occluded at once, and later biopsy specimens show the immediate and long-term lasting occlusion effect. While vessels are irradiated directly, they are usually irradiated to perforate, detailed causes are still under investigation. Animal experiments showed that the long pulse green laser therapy is a safe and effective solution to the vein's occlusion, which promises such laser with high energy of each pulse and 30-50 ms duration is an ideal candidate for vessel diseases treatment.

  12. Multiscale Vessel-guided Airway Tree Segmentation

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Sporring, Jon; de Bruijne, Marleen

    2009-01-01

    that is trained to differentiate between airway and non-airway voxels. Vessel and airway orientation information are used in the form of a vessel orientation similarity measure, which indicates how similar the orientation of the an airway candidate is to the orientation of the neighboring vessel. The method...... is evaluated within EXACT’09 on a diverse set of CT scans. Results show a favorable combination of a relatively large portion of the tree detected correctly with very few false positives....

  13. Exponential Stabilization of an Underactuated Surface Vessel

    Directory of Open Access Journals (Sweden)

    Kristin Y. Pettersen

    1997-07-01

    Full Text Available The paper shows that a large class of underactuated vehicles cannot be asymptotically stabilized by either continuous or discontinuous state feedback. Furthermore, stabilization of an underactuated surface vessel is considered. Controllability properties of the surface vessels is presented, and a continuous periodic time-varying feedback law is proposed. It is shown that this feedback law exponentially stabilizes the surface vessel to the origin, and this is illustrated by simulations.

  14. BIOASSAY VESSEL FAILURE ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Vormelker, P

    2008-09-22

    Two high-pressure bioassay vessels failed at the Savannah River Site during a microwave heating process for biosample testing. Improper installation of the thermal shield in the first failure caused the vessel to burst during microwave heating. The second vessel failure is attributed to overpressurization during a test run. Vessel failure appeared to initiate in the mold parting line, the thinnest cross-section of the octagonal vessel. No material flaws were found in the vessel that would impair its structural performance. Content weight should be minimized to reduce operating temperature and pressure. Outer vessel life is dependent on actual temperature exposure. Since thermal aging of the vessels can be detrimental to their performance, it was recommended that the vessels be used for a limited number of cycles to be determined by additional testing.

  15. Evolution of occlusal pathology. A literature review.

    OpenAIRE

    2013-01-01

    Introduction: Many of the guidelines on occlusion and treatment alternatives in dentate and partially edentulous patients, are based on concepts raised in the beginning of dentistry. The diversity of the occlusion schools has become some of these concepts complex to understand and apply. This diversity makes difficult the compression of the occlusal physiology and its disorders, hindering the understanding of the occlusal pathology and its proper diagnosis and management. Objective: This is w...

  16. New aspects of MRI for diagnostics of large vessel vasculitis and primary angiitis of the central nervous system; Neue Aspekte der MRT-Bildgebung zur Diagnostik der Grossgefaessvaskulitiden sowie der primaeren Angiitis des zentralen Nervensystems

    Energy Technology Data Exchange (ETDEWEB)

    Saam, T.; Habs, M.; Cyran, C.C.; Grimm, J.; Reiser, M.F.; Nikolaou, K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Pfefferkorn, T. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Klinik und Poliklinik fuer Neurologie, Muenchen (Germany); Schueller, U. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Zentrum fuer Neuropathologie, Muenchen (Germany)

    2010-10-15

    Vasculitis is a rare disease and clinical symptoms are often unspecific. Accurate and early diagnosis is mandatory in order to prevent complications, such as loss of vision or stroke. Imaging techniques can contribute to establishing a definite diagnosis and to evaluate disease activity and the extent of the disease in various vascular regions. Conventional imaging methods, such as computed tomography (CT) and magnetic resonance (MR) angiography, as well as digital subtraction angiography allow the vessel lumen but not the vessel wall to be depicted. However, vasculitis is a disease which primarily affects the vessel wall, therefore conventional imaging modalities often fail to make a definite diagnosis. Recently black-blood high resolution MR in vivo imaging has been used to visualize cervical and intracranial vasculitis. This review article presents imaging protocols for intracranial and cervical black-blood MR imaging and clinical cases with large vessel vasculitis and vasculitis of the central nervous system. Furthermore the current literature, examples of the most common differential diagnoses of cervical and cranial arteriopathy and the potential of other imaging modalities, such as PET/CT and ultrasound will be discussed. (orig.) [German] Vaskulitiden sind seltene Erkrankungen, deren klinische Symptome oft unspezifisch sind und deren genaue und fruehzeitige Diagnose daher eine besondere Herausforderung fuer jeden Kliniker darstellt. Hierzu kann die Bildgebung einen wertvollen Beitrag leisten und ist insbesondere in der Lage, das Ausmass der Erkrankung und die Anzahl der betroffenen Gefaesse zu bestimmen. Die klassischen bildgebenden Verfahren wie CT- (CTA) oder MR-Angiographie (MRA) sowie die digitale Subtraktionsangiographie (DSA) fokussieren dabei hauptsaechlich auf Veraenderungen des Lumendurchmessers, die Gefaesswand wird mit diesen Verfahren in der Regel nur unzureichend dargestellt. Ultraschalluntersuchungen lassen zwar eine Beurteilung des Lumens und

  17. A software application for comparing large numbers of high resolution MALDI-FTICR MS spectra demonstrated by searching candidate biomarkers for glioma blood vessel formation

    NARCIS (Netherlands)

    M.K. Titulaer (Mark); D.A.M. Mustafa (Dana); I. Siccama (Ivar); M. Konijnenburg (Marco); P.C. Burgers (Peter); A.C. Andeweg (Arno); P.A. Smitt (Peter); J.M. Kros (Johan); T.M. Luider (Theo)

    2008-01-01

    textabstractBackground: A Java™ application is presented, which compares large numbers (n > 100) of raw FTICR mass spectra from patients and controls. Two peptide profile matrices can be produced simultaneously, one with occurrences of peptide masses in samples and another with the intensity of comm

  18. Subintimal angioplasty for femoro-popliteal occlusive disease.

    Science.gov (United States)

    Markose, George; Miller, Fiona N A C; Bolia, Amman

    2010-11-01

    There has been a longstanding debate about the roles of surgical bypass graft, percutaneous transluminal angioplasty, subintimal angioplasty, and conservative management for femoro-popliteal occlusive disease. Subintimal angioplasty was first described in 1987 as a method of performing an endovascular arterial bypass. The subintimal space at the start of the occlusion is entered with a catheter and a wire loop is used to cross the occlusion and reenter the vessel lumen distally. In patients with critical limb ischemia, there is high quality evidence demonstrating that the limb salvage rate and amputation-free survival rates for surgery and endovascular treatment are similar, but surgery is more expensive than angioplasty in the short term. In patients with intermittent claudication, surgical bypass using an autologous saphenous vein graft is currently believed to be the gold standard, but this is increasingly questioned in the light of recent advances in endovascular techniques. Surgical bypass with vein graft offers a 2-year patency of 81%, compared with 67% for a polytetrafluoroethylene (PTFE) graft and at best 67% for subintimal angioplasty. The better patency offered by surgery must be balanced against a higher morbidity and mortality. To conclude, subintimal angioplasty is an extremely valuable technique in the management of critical limb ischemia. Based on the evidence to date, this technique is likely to have an increasing role in the management of intermittent claudication over the coming years, particularly if the risk of general anaesthesia is high or there is no suitable vein.

  19. Analyzing Vessel Behavior Using Process Mining

    NARCIS (Netherlands)

    Maggi, F.M.; Mooij, A.J.; Aalst, W.M.P. van der

    2013-01-01

    In the maritime domain, electronic sensors such as AIS receivers and radars collect large amounts of data about the vessels in a certain geographical area. We investigate the use of process mining techniques for analyzing the behavior of the vessels based on these data. In the context of maritime sa

  20. Analyzing Vessel Behavior Using Process Mining

    NARCIS (Netherlands)

    Maggi, F.M.; Mooij, A.J.; Aalst, W.M.P. van der

    2013-01-01

    In the maritime domain, electronic sensors such as AIS receivers and radars collect large amounts of data about the vessels in a certain geographical area. We investigate the use of process mining techniques for analyzing the behavior of the vessels based on these data. In the context of maritime sa

  1. Vessel Arrival Info - Legacy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Arrival Info is a spreadsheet that gets filled out during the initial stage of the debriefing process by the debriefer. It contains vessel name, trip...

  2. Guam Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Guam. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  3. Florida Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Florida. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  4. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  5. ACUTE RETINAL ARTERIAL OCCLUSIVE DISORDERS

    Science.gov (United States)

    Hayreh, Sohan Singh

    2011-01-01

    The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97 minutes produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4 hours the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wools spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities – non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual

  6. Occlusal stability in shortened dental arches.

    Science.gov (United States)

    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.

  7. Vertex occlusal radiography in localizing unerupted mesiodentes

    Directory of Open Access Journals (Sweden)

    P Chalakkal

    2011-01-01

    Full Text Available The aim was to compare the vertex occlusal projection with the anterior maxillary occlusal projection in localizing the position of mesiodentes. Mesiodentes were observed in an 8-year-old boy with an anterior maxillary occlusal radiograph. A vertex occlusal radiograph was taken to compare it with the former in terms of mesiodentes localization with respect to the maxillary central incisors. The vertex occlusal radiograph provided greater details of the position and proximity of mesiodentes with respect to the long axis of maxillary central incisors in comparison to the anterior maxillary occlusal radiograph. Vertex occlusal radiography is an important diagnostic tool in diagnosing the presence, position, and proximity of mesiodentes with respect to the long axis of normally aligned maxillary central incisors. However, it is not recommended for routine use in a patient as its radiation dose is higher than conventional intraoral radiographic methods.

  8. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  9. Correlation between optic nerve head circulation and visual function before and after anti-VEGF therapy for central retinal vein occlusion: prospective, interventional case series.

    Science.gov (United States)

    Nagasato, Daisuke; Mitamura, Yoshinori; Semba, Kentaro; Akaiwa, Kei; Nagasawa, Toshihiko; Yoshizumi, Yuki; Tabuchi, Hitoshi; Kiuchi, Yoshiaki

    2016-04-05

    To determine the correlation between the optic nerve head (ONH) circulation determined by laser speckle flowgraphy and the best-corrected visual acuity or retinal sensitivity before and after intravitreal bevacizumab or ranibizumab for central retinal vein occlusion. Thirty-one eyes of 31 patients were treated with intravitreal bevacizumab or ranibizumab for macular edema due to a central retinal vein occlusion. The blood flow in the large vessels on the ONH, the best-corrected visual acuity, and retinal sensitivity were measured at the baseline, and at 1, 3, and 6 months after treatment. The arteriovenous passage time on fluorescein angiography was determined. The venous tortuosity index was calculated on color fundus photograph by dividing the length of the tortuous retinal vein by the chord length of the same segment. The blood flow was represented by the mean blur rate (MBR) determined by laser speckle flowgraphy. To exclude the influence of systemic circulation and blood flow in the ONH tissue, the corrected MBR was calculated as MBR of ONH vessel area - MBR of ONH tissue area in the affected eye divided by the vascular MBR - tissue MBR in the unaffected eye. Pearson's correlation tests were used to determine the significance of correlations between the MBR and the best-corrected visual acuity, retinal sensitivity, arteriovenous passage time, or venous tortuosity index. At the baseline, the corrected MBR was significantly correlated with the arteriovenous passage time and venous tortuosity index (r = -0.807, P retinal sensitivity at the baseline, and at 1, 3, and 6 months (all P retinal sensitivity at 6 months (r = 0.485, P = 0.005). The pre-treatment blood flow velocity of ONH can be used as a predictive factor for the best-corrected visual acuity and retinal sensitivity after anti-VEGF therapy for central retinal vein occlusion. UMIN000009072. Date of registration: 10/15/2012.

  10. Acute Stroke and Obstruction of the Extracranial Carotid Artery Combined with Intracranial Tandem Occlusion: Results of Interventional Revascularization

    Energy Technology Data Exchange (ETDEWEB)

    Lescher, Stephanie, E-mail: stephanie.lescher@kgu.de; Czeppan, Katja; Porto, Luciana [Hospital of Goethe University, Institute of Neuroradiology (Germany); Singer, Oliver C. [Hospital of Goethe University, Department of Neurology (Germany); Berkefeld, Joachim [Hospital of Goethe University, Institute of Neuroradiology (Germany)

    2015-04-15

    PurposeDue to high thrombus load, acute stroke patients with tandem obstructions of the extra- and intracranial carotid arteries or the middle cerebral artery show a very limited response to systemic thrombolysis. Interventional treatment with mechanical thrombectomy—often in combination with acute stenting of underlying atherosclerotic stenosis or dissection—is increasingly used. It has been shown that such complex interventions are technically feasible. The lack of optimal management strategies and clinical data encouraged us to review our acute stroke interventions in patient with anterior circulation tandem lesions to determine lesion patterns, interventional approaches, and angiographic or clinical outcomes.Patients and MethodsWe retrospectively analyzed a series of 39 consecutive patients with intracranial vessel occlusion of the anterior circulation simultaneously presenting with high-grade cervical internal carotid artery (ICA) stenosis or occlusion.ResultsEmergency ICA stent implantation was technically feasible in all patients, and intracranial recanalization with TICI ≥ 2b was reached in a large number of patients (64 %). Good clinical outcomes (mRS ≤ 2 at 3 months) were achieved in one third of the patients (36 %). Symptomatic hemorrhages occurred in four patients (10 %). Mortality was 10 %.ConclusionEndovascular recanalization of acute cervical carotid artery occlusion was technically feasible in all patients, and resulted in high extra- and intracranial revascularization rates. A trend for favorable clinical outcome was seen in a higher TICI score, younger age, good collateral status, and combined IV rTPA and endovascular therapy.

  11. Tracking facial features with occlusions

    Institute of Scientific and Technical Information of China (English)

    MARKIN Evgeny; PRAKASH Edmond C.

    2006-01-01

    Facial expression recognition consists of determining what kind of emotional content is presented in a human face.The problem presents a complex area for exploration, since it encompasses face acquisition, facial feature tracking, facial expression classification. Facial feature tracking is of the most interest. Active Appearance Model (AAM) enables accurate tracking of facial features in real-time, but lacks occlusions and self-occlusions. In this paper we propose a solution to improve the accuracy of fitting technique. The idea is to include occluded images into AAM training data. We demonstrate the results by running ex periments using gradient descent algorithm for fitting the AAM. Our experiments show that using fitting algorithm with occluded training data improves the fitting quality of the algorithm.

  12. Cannabis, Collaterals, and Coronary Occlusion

    Directory of Open Access Journals (Sweden)

    Kalpa De Silva

    2011-01-01

    Full Text Available A 51-year-old gentleman, who regularly smoked cannabis, presented with chest pain and diaphoresis. He was haemodynamically stable. ECG showed ST depression, inferiorly, and 1 mm ST elevation in lead aVR. Emergent coronary angiography showed thrombotic occlusion of the left main coronary artery (LMCA, the dominant RCA provided Rentrop grade II collaterals to the LAD. The LMCA was successfully reopened by deployment of a bare-metal stent. Animal heart models suggest that endogenous cannibinoids may cause ischaemic preconditioning. This case suggests that the severity of ischaemia, and hence ECG changes and haemodynamic consequences following an acute occlusion of the LMCA, can be ameliorated by coronary collateralisation and possibly by preconditioning of the myocardium.

  13. Occlusal status among Yemeni children

    Directory of Open Access Journals (Sweden)

    Nabil M Al-Zubair

    2014-01-01

    Full Text Available Objectives: The purpose of this study was to assess the occlusal status in schoolchildren in Yemen, and to compare the results with those of other studies. Materials and Methods: The sample for this epidemiological survey consisted of 3003 primary school students, half of whom were boys and the other half girls, aged 12 years. The subjects were randomly selected, and none had received previous orthodontic treatment. Variables examined included intra-arch irregularities and malalignment (crowding and spacing in the incisal segments of the arch and midline diastema and discrepancies in occlusal contact relationship (maxillary overjet, mandibular overjet, anterior openbite and antero-posterior molar relation. Results: The results showed that about 26.1% of the subjects were still in the late mixed dentition stage and 73.9% presented with a dentition in the early permanent stage. Normal overjet was found in 55% of the sample. Crowding was observed in 31.4% of the subjects and midline diastema in 14.2%. Conclusion: Occlusal status among Yemeni children was characterized by a relatively high frequency of dental crowding, as well as a relatively high frequency of anterior mandibular overjet (Class III malocclusions.

  14. Immediate Small Side Branch Occlusion after Percutaneous Coronary Intervention

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Ostovan

    2007-09-01

    Full Text Available Background: Small side branches, albeit less important than their larger counterparts, have not yet received due attention in the literature. Nor has there ever been a comparison between drug-eluting stents and bare metal stents apropos side branch occlusion. The aim of this study was to compare the patency of small (≥0.5 and ≤1.5 mm in diameter side branches with respect to bare metal vs. drug-eluting stents immediately after their deployment.Methods: This prospective bi-center study, conducted between June 2005 and January 2007, enrolled 82 patients treated with ≥1 of two stents (TAXUSTM LiberteTM or LiberteTM. Side branches ≥0.5 and <1.5 mm in diameter arising from the main vessel at the lesion site were evaluated. Results: Thirty-eight patients were treated with 42 LiberteTM stents (58 side branches and forty-four patients with 50 TAXUSTM LiberteTM (102 side branches. The rate of small side branch occlusion was 35.3% (36 in the TAXUSTM LiberteTM group compared to 29.31% (15 in the LiberteTM group (P-value= 0.7. The presence of type 1 side branch morphology (Lefevre classification was the most powerful predictor of small side branch occlusion (P-value=0.03. Conclusion: This study shows that drug-eluting stents are not inferior to bare metal stents as regards small side branch occlusion during coronary stenting

  15. Erosion and break-up of light-gas layers by a horizontal jet in a multi-vessel, large-scale containment test system

    Energy Technology Data Exchange (ETDEWEB)

    Zboray, Robert, E-mail: robert.zboray@psi.ch; Mignot, Guillaume; Kapulla, Ralf; Paladino, Domenico

    2015-09-15

    The distribution and eventual stratification of hydrogen released during a hypothetical severe accident and the stability of the stratification formed in the early phase of the transient is of particular safety concern in Light Water Reactors (LWRs). The large-scale containment test facility PANDA (PSI, Switzerland) has been used to perform a series of four tests examining the erosion and break-up of stratified light-gas layers in the frame of the OECD SETH-2 project. The ultimate goal of the test program is to set-up an experimental data base of high-quality and high-density data that can challenge and validate 3D containment codes like e.g. GOTHIC, GASFLOW or MARS and validate the applicability of CFD codes like FLUENT or CFX for LWR containment problems. The test series discussed here focuses on the erosion of a stratified, helium-rich layer by horizontal steam injection at different locations below the layer. An approach with step-wise increasing complexity has been chosen to examine this problem allowing control over the rate of pressure increase and the occurrence of condensation. The step-wise approach enables a thorough understanding of the influence of different phenomena like position of steam injection, diffusion, pressurization and condensation on the behavior and erosion of the stratified layer.

  16. Atlantic Marine Mammal Assessment Vessel Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets are a compilation of large vessel surveys for marine mammal stock assessments in South Atlantic (Florida to Maryland) waters from 1994 to the...

  17. Caribbean Marine Mammal Assessment Vessel Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets are a compilation of large vessel surveys for marine mammal stock assessments in Caribbean waters conducted during 2000-2001. These surveys were...

  18. Influence of different narrative instructions to record the occlusal contact with silicone registration materials.

    Science.gov (United States)

    Obara, R; Komiyama, O; Iida, T; Asano, T; De Laat, A; Kawara, M

    2014-03-01

    This study examined the influence of narrative instructions on the occlusal contact area, occlusal contact point and masticatory muscle activities in normal subjects. Twelve healthy men and 12 healthy women with no more than one missing tooth per quadrant participated. Surface EMG was recorded from the masseter and temporal muscle. As a control measurement, intercuspal position was maintained to produce a habitual clenching record (NCR) while the occlusal contact area and occlusal contact point was recorded by means of silicone material. Subsequently, the occlusal contact area was recorded with the narrative instruction for minimum clenching record (MCR), light clenching record (LCR) and strong clenching record (HCR). While the EMG activity (%MVC) increased modestly from MCR to LCR (from 9·3 ± 2·0% to 11·5 ± 1·5%), the occlusal contact area increased rapidly (from 17·2 ± 11·3 mm(2) to 26·8 ± 15·6 mm(2) ) (P narrative instructions while recording the bite can result in largely stable occlusal contact area. An adequate narrative instruction may therefore contribute to taking a stable occlusal recording in natural dentition.

  19. The dental occlusion as a suspected cause for TMDs: epidemiological and etiological considerations.

    Science.gov (United States)

    Türp, J C; Schindler, H

    2012-07-01

    The relationship between the dental occlusion and temporomandibular disorders (TMDs) has been one of the most controversial topics in the dental community. In a large epidemiological cross-sectional survey - the Study of Health in Pomerania (Germany) - associations between 15 occlusion-related variables and TMD signs or symptoms were found. In other investigations, additional occlusal variables were identified. However, statistical associations do not prove causality. By using Hill's nine criteria of causation, it becomes apparent that the evidence of a causal relationship is weak. Only bruxism, loss of posterior support and unilateral posterior crossbite show some consistency across studies. On the other hand, several reported occlusal features appear to be the consequence of TMDs, not their cause. Above all, however, biological plausibility for an occlusal aetiology is often difficult to establish, because TMDs are much more common among women than men. Symptom improvement after insertion of an oral splint or after occlusal adjustment does not prove an occlusal aetiology either, because the amelioration may be due to the change of the appliance-induced intermaxillary relationship. In addition, symptoms often abate even in the absence of therapy. Although patients with a TMD history might have a specific risk for developing TMD signs, it appears more rewarding to focus on non-occlusal features that are known to have a potential for the predisposition, initiation or perpetuation of TMDs.

  20. Vessel involvement in giant cell arteritis : an imaging approach

    NARCIS (Netherlands)

    Holm, Pieter W; Sandovici, Maria; Slart, Riemer H.; Glaudemans, Andor W; Rutgers, Abraham; Brouwer, Elisabeth

    2016-01-01

    Vasculitis is classified based on the size of the involved vessels. The two major forms are small vessel vasculitis (SVV) and large vessel vasculitis (LVV). Main forms of LVV are Takayasu Arteritis (TA), Giant Cell Arteritis (GCA), Isolated Aortitis (IA) and Chronic Periaortitis (PC). This manuscrip

  1. Branch Retinal Vein Occlusion and Its Management

    Institute of Scientific and Technical Information of China (English)

    Desmond; Archer

    1992-01-01

    The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...

  2. 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.

  3. Percutaneous laser thermal angioplasty: initial clinical results with a laser probe in total peripheral artery occlusions.

    Science.gov (United States)

    Cumberland, D C; Sanborn, T A; Tayler, D I; Moore, D J; Welsh, C L; Greenfield, A J; Guben, J K; Ryan, T J

    1986-06-28

    A metal-tipped laser fibre was used during percutaneous angioplasty of femoral/popliteal or iliac artery occlusions in 56 patients. Primary success was achieved in 50 (89%) of these total occlusions, providing a channel for subsequent balloon dilatation. Before the procedure, 18 lesions had been judged untreatable by conventional angioplasty and four of the six failures were in these. Complications directly attributable to the laser probe were one case of vessel perforation and two cases of entry into vessel walls; these had no sequelae. Other acute complications were a distal thrombosis in a non-heparinised patient, requiring local streptokinase treatment, and two reocclusions and one transient peripheral embolic episode in the first 24 hours. The laser probe technique has potential for increasing the proportion of patients suitable for angioplasty.

  4. Pressure vessel design manual

    CERN Document Server

    Moss, Dennis R

    2013-01-01

    Pressure vessels are closed containers designed to hold gases or liquids at a pressure substantially different from the ambient pressure. They have a variety of applications in industry, including in oil refineries, nuclear reactors, vehicle airbrake reservoirs, and more. The pressure differential with such vessels is dangerous, and due to the risk of accident and fatality around their use, the design, manufacture, operation and inspection of pressure vessels is regulated by engineering authorities and guided by legal codes and standards. Pressure Vessel Design Manual is a solutions-focused guide to the many problems and technical challenges involved in the design of pressure vessels to match stringent standards and codes. It brings together otherwise scattered information and explanations into one easy-to-use resource to minimize research and take readers from problem to solution in the most direct manner possible. * Covers almost all problems that a working pressure vessel designer can expect to face, with ...

  5. 大型舰船官兵睡眠质量及心理应激状况调查%Investigation on the sleep status and mental stress of the commissioned and enlisted onboard the large naval vessel

    Institute of Scientific and Technical Information of China (English)

    郑良成; 夏亮; 常大川; 包旭芳; 陈佩; 林军; 勉闻光

    2015-01-01

    目的 调查大型舰船官兵睡眠状况及心理应激程度.方法 对大型舰船80名青年官兵采用匹兹堡睡眠质量量表(Pittsburgh sleep quality index,PSQI)、急性应激反应量表(acute stress response scale,ASRS),对其睡眠状况、心理应激程度进行抽样调查及统计分析.结果 (1)夜间平均睡眠时间(5.61±1.84)h,PSQI总得分为8.05 ±3.55,61.9%受检者存在睡眠障碍问题.(2)睡眠障碍组官兵以入睡困难最常见,其他还有睡眠时间减少、中途觉醒、早醒及多梦或梦魇等.(3)大型舰船官兵PSQI总分及各因子如睡眠效率、睡眠障碍和日间功能障碍均与情绪反应、行为变化呈正相关.结论 大型舰船官兵睡眠状况存在一定问题,心理应激程度较重,应采用心理疏导、改善环境等干预措施,以改善大型舰船官兵睡眠状况,促进睡眠健康.%Objective To investigate the sleep status and mental stress of the commissioned and enlisted onboard the large naval vessel.Methods Sample surveys and statistical analyses were made on the sleep status and mental stress of 80 commissioned and enlisted personnel onboard the large naval vessel by using Pittsburgh Sleep Quality Index (PQSI) and Acute Stress Response Scale (ASRS).Results (1) The average sleep time at night was (5.61 ± 1.84) hours,and total scores of PSQI were (8.05 ± 3.55).Survey results indicated that 61.9% of the subjects had sleep disorder.(2) The most common problem of sleep disorder among the commissioned and enlisted personnel was difficult in falling asleep,and other problems were reduced sleep time,wake-up during sleep,early awakening,having dreams or nightmares.(3) Total PSQI scores and various factors such as sleep efficiency,sleep disorder,and daytime dysfunction were all positively correlated with emotional response and changes in behavior.Conclusions There existed certain problems in the overall sleep status and mental stress among the commissioned and enlisted onboard

  6. Occlusal considerations for dental implant restorations.

    Science.gov (United States)

    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.

  7. Optical coherence tomography angiography of retinal vascular occlusions produced by imaging-guided laser photocoagulation

    Science.gov (United States)

    Soetikno, Brian T.; Shu, Xiao; Liu, Qi; Liu, Wenzhong; Chen, Siyu; Beckmann, Lisa; Fawzi, Amani A.; Zhang, Hao F.

    2017-01-01

    Retinal vascular occlusive diseases represent a major form of vision loss worldwide. Rodent models of these diseases have traditionally relied upon a slit-lamp biomicroscope to help visualize the fundus and subsequently aid delivery of high-power laser shots to a target vessel. Here we describe a multimodal imaging system that can produce, image, and monitor retinal vascular occlusions in rodents. The system combines a spectral-domain optical coherence tomography system for cross-sectional structural imaging and three-dimensional angiography, and a fluorescence scanning laser ophthalmoscope for Rose Bengal monitoring and high-power laser delivery to a target vessel. This multimodal system facilitates the precise production of occlusions in the branched retinal veins, central retinal vein, and branched retinal arteries. Additionally, changes in the retinal morphology and retinal vasculature can be longitudinally documented. With our device, retinal vascular occlusions can be easily and consistently created, which paves the way for futures studies on their pathophysiology and therapeutic targets. PMID:28856036

  8. Occlusion Handling via Random Subspace Classifiers for Human Detection.

    Science.gov (United States)

    Marín, Javier; Vázquez, David; López, Antonio M; Amores, Jaume; Kuncheva, Ludmila I

    2014-03-01

    This paper describes a general method to address partial occlusions for human detection in still images. The random subspace method (RSM) is chosen for building a classifier ensemble robust against partial occlusions. The component classifiers are chosen on the basis of their individual and combined performance. The main contribution of this work lies in our approach's capability to improve the detection rate when partial occlusions are present without compromising the detection performance on non occluded data. In contrast to many recent approaches, we propose a method which does not require manual labeling of body parts, defining any semantic spatial components, or using additional data coming from motion or stereo. Moreover, the method can be easily extended to other object classes. The experiments are performed on three large datasets: the INRIA person dataset, the Daimler Multicue dataset, and a new challenging dataset, called PobleSec, in which a considerable number of targets are partially occluded. The different approaches are evaluated at the classification and detection levels for both partially occluded and non-occluded data. The experimental results show that our detector outperforms state-of-the-art approaches in the presence of partial occlusions, while offering performance and reliability similar to those of the holistic approach on non-occluded data. The datasets used in our experiments have been made publicly available for benchmarking purposes.

  9. Assessment of occlusion curriculum in predoctoral dental education: report from ACP Task Force on Occlusion Education.

    Science.gov (United States)

    Lee, Damian J; Wiens, Jonathan P; Ference, John; Donatelli, David; Smith, Rick M; Dye, Bryan D; Obrez, Ales; Lang, Lisa A

    2012-10-01

    The purposes of this report were to (1) assess the current occlusion curriculum in the predoctoral prosthodontic education of US dental institutions and (2) to examine the opinions of faculty, course directors, and program directors on the contents of occlusion curriculum. The Task Force on Occlusion Education from the American College of Prosthodontists (ACP) conducted two surveys using a web-based survey engine: one to assess the current status of occlusion education in predoctoral dental education and another to examine the opinions of faculty and course directors on the content of occlusion curriculum. The sections in the surveys included demographic information, general curriculum information, occlusion curriculum for dentate patients, occlusion curriculum for removable prosthodontics, occlusion curriculum for implant prosthodontics, temporomandibular disorder (TMD) curriculum, teaching philosophy, concepts taught, and methods of assessment. The results from the surveys were compiled and analyzed using descriptive statistics. The results from the two surveys on general concepts taught in occlusion curriculum were sorted and compared for discrepancies. According to the predoctoral occlusion curriculum surveys, canine guidance was preferred for dentate patients, fixed prosthodontics, and fixed implant prosthodontics. Bilateral balanced occlusion was preferred for removable prosthodontics and removable implant prosthodontics. There were minor differences between the two surveys regarding the occlusion concepts being taught and the opinions of faculty members teaching occlusion. Two surveys were conducted regarding the current concepts being taught in occlusion curriculum and the opinions of educators on what should be taught in occlusion curriculum. An updated and clearly defined curriculum guideline addressing occlusion in fixed prosthodontics, removable prosthodontics, implant prosthodontics, and TMD is needed. © 2012 by the American College of Prosthodontists.

  10. Maury Journals - German Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — German vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  11. NCSX Vacuum Vessel Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Viola, M. E.; Brown, T.; Heitzenroeder, P.; Malinowski, F.; Reiersen, W.; Sutton, L.; Goranson, P.; Nelson, B.; Cole, M.; Manuel, M.; McCorkle, D.

    2005-10-07

    The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The vessel is being fabricated by Major Tool and Machine, Inc. (MTM) in three identical 120º vessel segments, corresponding to the three NCSX field periods, in order to accommodate assembly of the device. The port extensions are welded on, leak checked, cut off within 1" of the vessel surface at MTM and then reattached at PPPL, to accommodate assembly of the close-fitting modular coils that surround the vessel. The 120º vessel segments are formed by welding two 60º segments together. Each 60º segment is fabricated by welding ten press-formed panels together over a collapsible welding fixture which is needed to precisely position the panels. The vessel is joined at assembly by welding via custom machined 8" (20.3 cm) wide spacer "spool pieces." The vessel must have a total leak rate less than 5 X 10-6 t-l/s, magnetic permeability less than 1.02μ, and its contours must be within 0.188" (4.76 mm). It is scheduled for completion in January 2006.

  12. Modeling of the principal dimensions of large vessels based on a BPNN trained by an improved PSO%改进PSO训练的BPNN方法的舰船主尺度建模

    Institute of Scientific and Technical Information of China (English)

    张海鹏; 韩端锋; 郭春雨

    2012-01-01

    利用改进粒子群优化算法训练的BP神经网络(BPNN)对以航母为代表的大型舰船主尺度进行了回归分析.对粒子群优化算法(PSO)的学习因子进行了关于迭代进程的自适应调整,并将改进后的PSO算法对BPNN训练过程进行优化.利用新型BPNN对典型航母主尺度(总长、总宽、设计水线长、设计水线宽、吃水与满载排水量)进行数学建模,与基于传统多项式回归的结果进行对比分析.结果表明经改进PSO训练的BPNN具有更高的输出精度且具有良好的分段光滑特性,这对于大型舰船方案论证与总体设计可起到重要的指导性作用.%A back propagation neural network (BPNN) trained by an improved particle swarm optimization (PSO) was applied to the principal dimensions of large vessels by regression analysis.First,the improved PSO learning factors concerning the iterative process were adjusted adaptively and the BPNN trained process was optimized by using an improved PSO.Secondly,a new BPNN method was applied to establish a mathematic model of an aircraft's principal dimensions (including overall length,breadth moulded,length of the design waterline,breadth of the design waterline,draft,and full load displacement).Finally,compared with the results of traditional polynomial regression,a BPNN trained by an improved PSO has higher accuracy and fine characteristics of smooth at every subsection.Therefore,the mathematic model has a guidance effect on the scheme demonstration and overall design of large vessels.

  13. Occlusion in the combination fixed removable prosthodontic patient.

    Science.gov (United States)

    Ivanhoe, J R; Vaught, R D

    1987-07-01

    The authors provide a review of the critical aspects of occlusion for the combination fixed removable patient. Articular selection and jaw relation techniques are reviewed, and dental materials combinations are recommended for restoring opposing occlusal surfaces. General objectives and specific recommendations for determining and establishing occlusal schemes are made. Tables outlining occlusal scheme, occlusal morphology, and degree of balance are presented.

  14. 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.

  15. Lower Body Positive Pressure Application with an Antigravity Suit in Acute Carotid Occlusion

    Directory of Open Access Journals (Sweden)

    Karine Berthet

    2010-01-01

    Full Text Available 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.

  16. Spontaneous occlusion of traumatic carotid-cavernous fistula - the effect of angiography

    Energy Technology Data Exchange (ETDEWEB)

    Stampfel, G.

    1984-08-01

    In two patients with a traumatic carotid-cavernous fistula, permanent occlusion of the lesion was observed following cerebral angiography and confirmed by further angiography. A delay is therefore recommended between performing angiography and carrying out further treatment, which may carry some risk. Possibly the use of ionic contrast media, which irritate the vessels, compression of the carotid artery, which reduces flow through the fistula, and general anaesthesia, which may drop the blood pressure, initiate thrombosis in the cavernous sinus. 3 figs.

  17. L/B参数对双桨大长宽比超肥大船型阻力性能的影响%The Effect of L/B Parameters on the Hampered Performance of an Ultra-Large Vessel with Twin Screws and Large Length-width Ratio

    Institute of Scientific and Technical Information of China (English)

    黄广茂

    2011-01-01

    In order to discuss the effect of parameters on the resisted performance of an ultra-large ship with twin propellers and large length-width ratio, and to establish the quantitative forecasting system of effective power of this land of vessel, the author makes the L/B serial ship model tests after series of B/T and Cb tests. Four model vessels are involved in the L/B tests, with each tested with three hydrostatic resistance of different displacement. The tests generate the coefficient map of remaining resistance within the range ofL/B=8.0~11.65 and the map showing the effect of L/B parameters on the remaining resistance coefficient for correction, which offers some conclusions which will surely benefit the vessel designers.%为了探讨船型参数L/B对双桨大长宽比超肥大船型阻力性能的影响,建立该船型有效功率的定量预报系统,作者在B/T系列和CB系列船模试验之后,又进行了L/B系列船模试验.L/B系列船模共4艘,通过每条船模3个不同排水量的静水阻力试验,给出了L/B=8.0~11.65范围的剩余阻力系数图谱和L/B参数影响对剩余阻力系数的修正图谱,获得了一些有益的结论,供设计部门使用参考.

  18. Probabilistic atlas based labeling of the cerebral vessel tree

    Science.gov (United States)

    Van de Giessen, Martijn; Janssen, Jasper P.; Brouwer, Patrick A.; Reiber, Johan H. C.; Lelieveldt, Boudewijn P. F.; Dijkstra, Jouke

    2015-03-01

    Preoperative imaging of the cerebral vessel tree is essential for planning therapy on intracranial stenoses and aneurysms. Usually, a magnetic resonance angiography (MRA) or computed tomography angiography (CTA) is acquired from which the cerebral vessel tree is segmented. Accurate analysis is helped by the labeling of the cerebral vessels, but labeling is non-trivial due to anatomical topological variability and missing branches due to acquisition issues. In recent literature, labeling the cerebral vasculature around the Circle of Willis has mainly been approached as a graph-based problem. The most successful method, however, requires the definition of all possible permutations of missing vessels, which limits application to subsets of the tree and ignores spatial information about the vessel locations. This research aims to perform labeling using probabilistic atlases that model spatial vessel and label likelihoods. A cerebral vessel tree is aligned to a probabilistic atlas and subsequently each vessel is labeled by computing the maximum label likelihood per segment from label-specific atlases. The proposed method was validated on 25 segmented cerebral vessel trees. Labeling accuracies were close to 100% for large vessels, but dropped to 50-60% for small vessels that were only present in less than 50% of the set. With this work we showed that using solely spatial information of the vessel labels, vessel segments from stable vessels (>50% presence) were reliably classified. This spatial information will form the basis for a future labeling strategy with a very loose topological model.

  19. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner l

  20. 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...

  1. RETINAL VEIN OCCLUSIONS - A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Ramadevi

    2015-11-01

    Full Text Available Retinal vein occlusion is the most common retinal occlusive disorder encountered by opthalmologists and is usually associated with a variable amount of visual loss.The study was conducted over a period of 22 months, we performed a combined analysis of risk factors, clinical presentation, management and complication of these 51 patients

  2. Occlusion on oral implants: current clinical guidelines.

    Science.gov (United States)

    Koyano, K; Esaki, D

    2015-02-01

    Proper implant occlusion is essential for adequate oral function and the prevention of adverse consequences, such as implant overloading. Dental implants are thought to be more prone to occlusal overloading than natural teeth because of the loss of the periodontal ligament, which provides shock absorption and periodontal mechanoreceptors, which provide tactile sensitivity and proprioceptive motion feedback. Although many guidelines and theories on implant occlusion have been proposed, few have provided strong supportive evidence. Thus, we performed a narrative literature review to ascertain the influence of implant occlusion on the occurrence of complications of implant treatment and discuss the clinical considerations focused on the overloading factors at present. The search terms were 'dental implant', 'dental implantation', 'dental occlusion' and 'dental prosthesis'. The inclusion criteria were literature published in English up to September 2013. Randomised controlled trials (RCTs), prospective cohort studies and case-control studies with at least 20 cases and 12 months follow-up interval were included. Based on the selected literature, this review explores factors related to the implant prosthesis (cantilever, crown/implant ratio, premature contact, occlusal scheme, implant-abutment connection, splinting implants and tooth-implant connection) and other considerations, such as the number, diameter, length and angulation of implants. Over 700 abstracts were reviewed, from which more than 30 manuscripts were included. We found insufficient evidence to establish firm clinical guidelines for implant occlusion. To discuss the ideal occlusion for implants, further well-designed RCTs are required in the future.

  3. Retinal vein occlusion: pathophysiology and treatment options

    OpenAIRE

    Niral Karia

    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

  4. Symposium on semiprecision attachments in removable partial dentures. Occlusal relationships.

    Science.gov (United States)

    Whitbeck, P; Ivanhoe, J R

    1985-01-01

    This article discusses current concepts of occlusion and describes the methods of creating a physiologic occlusion for the partially edentulous patient. Specific recommendations are made for choices of materials, techniques, and occlusal schemes for various edentulous situations.

  5. Computerized analysis of occlusal contacts in bruxism patients treated with occlusal splint therapy

    Science.gov (United States)

    Kılınç, Halil İbrahim; Tuna, Süleyman Hakan; Özcan, Nihal

    2013-01-01

    PURPOSE Occlusal splints are commonly used to prevent tooth wear caused by bruxism. However, the effects of splints on occlusion are still unclear. Although it is rarely alluded in literature, splints can provoke severe occlusal alterations and other complications. This study was aimed to identify differences in the responses of individuals with bruxism and healthy individuals to a full-arch maxillary stabilization splint in terms of occlusal changes. MATERIALS AND METHODS Occlusal contacts in 20 (5 male, 15 female) bruxism patients and 20 (5 male, 15 female) controls with normal occlusion were evaluated before and after occlusal splint therapy. T-Scan III, a computerized occlusal analysis system, was used to simultaneously measure occlusion and disclusion times as well as left-right and anterior-posterior contact distributions before splint therapy and 3 months after therapy. Wilcoxon and Mann-Whitney U tests were used for statistical analyses (α=.05). RESULTS No differences were found in the posterior contact of bruxism patients before and after stabilization splint treatment. However, differences in posterior contact were observed between bruxists and normal individuals prior to treatment, and this difference disappeared following treatment. CONCLUSION The results of this study showed the use of a stabilization splint may not have an effect on occlusion. However, the area of posterior occlusal contact among bruxists was found to be greater than that of normal individuals. According to this study, the clinical use of splints may be harmless. PMID:24049566

  6. Atherosclerosis of coronary blood vessels - local or systemic inflamation?

    Science.gov (United States)

    Pejkov, Hristo; Kedev, Sasko; Panov, Saso; Srbinovska-Kostovska, Elizabeta; Lang, Irene

    2013-01-01

    The presence of atherosclerotic lesions in the blood vessels is a predisposition for the development and occurrence of acute ischaemic attacks. Bigger atherosclerotic lesions in the coronary blood vessels cause lumen occlusion, which is a cause of acute myocardial infarction. Endothelial dysfunction is defined as an ability of the endothelium to produce vasorelaxing nitric oxide (NO), or deregulation of the other vasoactive substances, such as angiotensin II and endothelin [13]. This definition describes endothelial dysfunction as an improper vasomotor constriction of the vessel, that leads to lumen occlusion of the already existing atherosclerotic lesions. According to the modern model, the development of atherosclerotic plaque and inappropriate endothelial NO production have a synergistic role in patho-physiological and molecular processes in the blood vessels [14]. Lesions in the coronary arteries are deposits of huge quantities of foamy cells and fibrous plaques. The thin fibrous plaques are 10-20% of the total plaque population and are the cause of 80-90% of clinical cases due to their ability to rupture [48]. According to all the results from published studies by far, it has been pointed out that the plaque stability, not the absolute size influences the rupture potential. Elucidating the risk factors that may modify in the atherogenesis and the consequent atherothrombic effect is the first step to this goal.

  7. [Dynamic bimaxillary osteotomy: the new occlusal base].

    Science.gov (United States)

    Audion, M; Darmon, Y

    1989-01-01

    The authors present an ortho-surgical method which unites occlusion and aesthetic without compromise and without stopping orthodontic work during the immediate post-operative period. The occlusal preparation permits us a global and simultaneous mobilisation of the two maxillars which are ostesynthezed in posterior skeletal disclosing. This disposition allows a lingual replacement and gives more facility to an eventual immediate post-operative occlusal replacement. The stiff osteosynthesis with immovable plates realize a therapeutic dissociation between the skeletal stage and the basal alveolo-dental stage. The "proprioceptive amnesia" and the "muscular sideration" permit a proprioceptive reorganisation and a new neuro-muscular fonctionnement elaborated from a new occlusal base. The free movements of the T.M.J. facilitate these acquisitions and allow a perspective supervision of the occlusion in a dynamic perspective.

  8. Virtual occlusion in planning orthognathic surgical procedures.

    Science.gov (United States)

    Nadjmi, N; Mollemans, W; Daelemans, A; Van Hemelen, G; Schutyser, F; Bergé, S

    2010-05-01

    Accurate preoperative planning is mandatory for orthognathic surgery. One of the most important aims of this planning process is obtaining good postoperative dental occlusion. Recently, 3D image-based planning systems have been introduced that enable a surgeon to define different osteotomy planes preoperatively and to assess the result of moving different bone fragments in a 3D virtual environment, even for soft tissue simulation of the face. Although the use of these systems is becoming more accepted in orthognathic surgery, few solutions have been proposed for determining optimal occlusion in the 3D planning process. In this study, a 3D virtual occlusion tool is presented that calculates a realistic interaction between upper and lower dentitions. It enables the surgeon to obtain an optimal and physically possible occlusion easily. A validation study, including 11 patient data sets, demonstrates that the differences between manually and virtually defined occlusions are small, therefore the presented system can be used in clinical practice.

  9. [Occlusal vertical dimension in removable complete dentures].

    Science.gov (United States)

    den Haan, R; Witter, D J

    2011-12-01

    In removable complete dentures, the occlusal vertical dimension is an important factor for patients' satisfaction with aesthetics. An excessively reduced occlusal vertical dimension is especially likely to lead to complaints about aesthetics, whereas an increased occlusal vertical dimension may lead to discomfort and a decision not to wear the complete dentures. There are various methods for determining the occlusal vertical dimension in complete dentures, based on the vertical dimension in the rest position of the mandible or on phonetics. However, none of the methods have proven to be clearly superior, in terms of reliability, than the others. The assessment of the occlusal vertical dimension will become more reliable if several methods are used simultaneously. Moreover, knowledge of the characteristics of the ageing face is essential.

  10. Fast Visual Object Tracking Using Modified kalman and Particle Filtering Algorithms in the Presence of Occlusions

    Directory of Open Access Journals (Sweden)

    G.Mallikarjuna Rao

    2014-09-01

    Full Text Available In the present day real time applications of visual object tracking in surveillance, it has become extremely complex, time consuming and tricky to do the tracking when there are occlusions are present for small duration or for longer time and also when it is done in outdoor environments. In these conditions, the target to be tracked can be lost for few seconds and that should be tracked as soon as possible. As from the literature it is observed that particle filter can be able to track the target robustly in different kinds of background conditions, and it’s robust to partial occlusion. However, this tracking cannot recover from large proportion of occlusion and complete occlusion, to avoid this condition, we proposed two new algorithms (modified kalman and modified particle filter for fast tracking of objects in the presence of occlusions. We considered the complete occlusion of tracking object and the main objective is how fast the system is able to track the object after the occlusion is crossed. From the experimental results, it is observed that the proposed algorithms have shown good improvement in results compared to the traditional methods.

  11. A Fast Ambient Occlusion Method for Real-Time Plant Rendering

    Institute of Scientific and Technical Information of China (English)

    Jun Teng; Marc Jaeger; Bao-Gang HU

    2007-01-01

    Global illumination effects are crucial for virtual plant rendering. Whereas real-time global illumination rendering of plants is impractical, ambient occlusion is an efficient alternative approximation. A tree model with millions of triangles is common, and the triangles can be considered as randomly distributed. The existing ambient occlusion methods fail to apply on such a type of object. In this paper, we present a new ambient occlusion method dedicated to real time plant rendering with limited user interaction. This method is a three-step ambient occlusion calculation framework which is suitable for a huge number of geometry objects distributed randomly in space. The complexity of the proposed algorithm is O(n), compared to the conventional methods with complexities of O(n2). Furthermore, parameters in this method can be easily adjusted to achieve flexible ambient occlusion effects. With this ambient occlusion calculation method, we can manipulate plant models with millions of organs, as well as geometry objects with large number of randomly distributed components with affordable time, and with perceptual quality comparable to the previous ambient occlusion methods.

  12. Occlusion for stimulus deprivation amblyopia

    Science.gov (United States)

    Antonio-Santos, Aileen; Vedula, Satyanarayana S; Hatt, Sarah R; Powell, Christine

    2014-01-01

    Background Stimulus deprivation amblyopia (SDA) develops due to an obstruction to the passage of light secondary to a condition such as cataract. The obstruction prevents formation of a clear image on the retina. SDA can be resistant to treatment, leading to poor visual prognosis. SDA probably constitutes less than 3% of all amblyopia cases, although precise estimates of prevalence are unknown. In developed countries, most patients present under the age of one year; in less developed parts of the world patients are likely to be older at the time of presentation. The mainstay of treatment is removal of the cataract and then occlusion of the better-seeing eye, but regimens vary, can be difficult to execute, and traditionally are believed to lead to disappointing results. Objectives Our objective was to evaluate the effectiveness of occlusion therapy for SDA in an attempt to establish realistic treatment outcomes. Where data were available, we also planned to examine evidence of any dose response effect and to assess the effect of the duration, severity, and causative factor on the size and direction of the treatment effect. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to October 2013), EMBASE (January 1980 to October 2013), the Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to October 2013), PubMed (January 1946 to October 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 28 October 2013. Selection criteria We planned

  13. Idiopathic pediatric retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Manayath George

    2010-01-01

    Full Text Available We report a case of branch retinal artery occlusion (BRAO in a healthy young girl. An eight-year-old girl presented with sudden loss of vision in her left eye. She had a pale retina with macular edema consistent with extensive BRAO. A thorough workup was performed to determine any etiologic factor. All test results were within normal limits. Her visual acuity improved from finger counting to 20/40 over two weeks, on immediate treatment with intravenous steroids (methyl prednisolone. This case suggests that BRAO can occur in healthy children without any detectable systemic or ocular disorders and a dramatic improvement may be achieved with prompt treatment with intravenous steroids.

  14. [Cilioretinal artery occlusion in hemochromatosis].

    Science.gov (United States)

    Peral, M J; Reche, A; Crespo, M J; Carpio, R; Gutierrez, O; Espino, A; Toledano, N

    2015-05-01

    We report a case of a 31 year-old woman with a sudden visual loss due to a cilioretinal artery occlusion. The physical examinination showed hepatomegaly. Serum iron and ferritin and transferrin saturation were unusually high. The doppler scan of carotid arteries showed no relevant signs of atheromatous disease. Dilated cardiomiopaty was revealed in the B-scan with subendocardial calcium deposits. Genetic tests were positive for hemochromatosis. Subendocardial calcification due to hemochromatosis could be the embolic source in our patient. This embolic ocular disease is the first presentation of hemochromatosis in this patient. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  15. Occlusion for maxillary dentures opposing osseointegrated mandibular prostheses.

    Science.gov (United States)

    Denissen, H W; Kalk, W; van Waas, M A; van Os, J H

    1993-01-01

    This paper presents a combination of several occlusal concepts designed to contribute to the successful use of maxillary dentures in opposition to osseointegrated mandibular prostheses. To ensure a positive outcome when designing such an occlusion, three factors must be considered: patient satisfaction, maxillary anterior bone preservation, and mandibular arch shortening. It is recommended that for centric occlusion the molars have a lingual contact occlusion, the premolars have a buccal contact occlusion, and the anterior teeth have an open occlusal relationship. For an eccentric occlusion, a balanced articulation is favored instead of mutually protected occlusion.

  16. Another novel application of Hem-o-Lok clips for transient vascular occlusion in robot-assisted laparoscopic partial nephrectomy: an alternative to laparoscopic bulldog and Satinsky clamps.

    Science.gov (United States)

    Ho, Henry Sun Sien; Peschel, Reinhard; Neururer, Richard; Steiner, Hannes; Schwentner, Christian; Bartsch, Georg

    2008-08-01

    We describe our technique of achieving transient vascular occlusion utilizing Hem-o-Lok clips during robotassisted laparoscopic partial nephrectomy (RLPN) A once-folded vascular loop is threaded through a 2-cm feeding tube. After passing around the renal vessel, its tail goes through the U-loop, creating a tourniquet. Vascular occlusion begins when the tube slides towards the vessel and a Hem-o-Lok clip is applied on the vascular loop next to the exposed end of the tube. When no longer needed, it is released. Since July 2006, 25 patients underwent RLPN utilizing this technique, which required bulldog or Satinsky clamps.

  17. Confinement Vessel Dynamic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    R. Robert Stevens; Stephen P. Rojas

    1999-08-01

    A series of hydrodynamic and structural analyses of a spherical confinement vessel has been performed. The analyses used a hydrodynamic code to estimate the dynamic blast pressures at the vessel's internal surfaces caused by the detonation of a mass of high explosive, then used those blast pressures as applied loads in an explicit finite element model to simulate the vessel's structural response. Numerous load cases were considered. Particular attention was paid to the bolted port connections and the O-ring pressure seals. The analysis methods and results are discussed, and comparisons to experimental results are made.

  18. Wound-induced vascular occlusions in Vitis vinifera (Vitaceae): Tyloses in summer and gels in winter1.

    Science.gov (United States)

    Sun, Qiang; Rost, Thomas L; Matthews, Mark A

    2008-12-01

    Vascular occlusion in xylem conduits is a common response to environmental stresses, and plant species are recognized as primarily tylose-forming or gel-forming. These stresses occur throughout the year, but there is little information on the wound responses throughout the year and in growing and dormant tissues. Wound-induced vascular occlusions were evaluated by type (tylose or gel), temporal progress, and spatial distribution for grape stems pruned in four seasons through an entire year. Tyloses were formed predominantly in summer and gels in winter. Cytohistological analyses indicated that wound-induced gels were pectin-rich. Both gel formation and tylose development were complete within 7 d and 10 mm from the cut regardless of the season of the wounding. Most vessels were affected by wounding, but a higher fraction of vessels developed occlusions in summer and autumn (over 80%) than in winter and spring (about 60%). The study is the first to show a single species is capable of producing primarily either tyloses or gels and that the type of wound-induced occlusion is dependent upon the season in which wounding occurs. Winter conditions limit the wound response to reversible gel formation that may contribute to refilling of embolized vessels in the spring.

  19. Free Flow of Qi in Conception Vessel and Governor Vessel Leading to Longevity

    Institute of Scientific and Technical Information of China (English)

    GUI Liang; CUI Yi-jun

    2003-01-01

    @@ Circle of Qi in human body, is namely Conception Vessel and Governor Vessel. It is divided into Large and Small Circle of qi. Small Circle of qi means that qi flows along the Circle of qi. Large Circle of qi means that vitality flows along the Circle of qi.Health-preserving expert holds that, if someone can achieve the skill of Small Circle of qi, he can return to juvenscence in essence, consolidating the body and achieve longevity.

  20. Disparity biasing in depth from monocular occlusions.

    Science.gov (United States)

    Tsirlin, Inna; Wilcox, Laurie M; Allison, Robert S

    2011-07-15

    Monocular occlusions have been shown to play an important role in stereopsis. Among other contributions to binocular depth perception, monocular occlusions can create percepts of illusory occluding surfaces. It has been argued that the precise location in depth of these illusory occluders is based on the constraints imposed by occlusion geometry. Tsirlin et al. (2010) proposed that when these constraints are weak, the depth of the illusory occluder can be biased by a neighboring disparity-defined feature. In the present work we test this hypothesis using a variety of stimuli. We show that when monocular occlusions provide only partial constraints on the magnitude of depth of the illusory occluders, the perceived depth of the occluders can be biased by disparity-defined features in the direction unrestricted by the occlusion geometry. Using this disparity bias phenomenon we also show that in illusory occluder stimuli where disparity information is present, but weak, most observers rely on disparity while some use occlusion information instead to specify the depth of the illusory occluder. Taken together our experiments demonstrate that in binocular depth perception disparity and monocular occlusion cues interact in complex ways to resolve perceptual ambiguity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Renal infarction caused by medium vessel vasculitis.

    Science.gov (United States)

    Kavarthapol Jayaraman, Vinothkumar; Chakera, Aron

    2015-04-24

    A 44-year-old Italian man presented to the emergency department on three occasions over 4 days with severe left flank pain. Initial investigations including a renal tract ultrasound were normal and he was discharged with analgaesia. On his third presentation, a CT angiogram was performed due to persisting pain, which demonstrated infarction of his left kidney as well as thickening of the anterior branch of left renal artery and complete occlusion with focal intimal dissection of the coeliac artery. His antineutrophil cytoplasmic antibody was negative. A medium vessel vasculitis was suspected and confirmed on positron emission tomography-CT, which revealed increased metabolic activity involving the right internal mammary artery and coeliac artery. Treatment with pulse methylprednisolone was started followed by a tapering prednisolone regimen, with a rapid reduction in his inflammatory indices. Twenty-four months later his renal function remains normal off all immunosuppression.

  2. Endovascular treatment strategies for supra-aortic arterial occlusive disease.

    Science.gov (United States)

    Peeters, P; Verbist, J; Deloose, K; Bosiers, M

    2005-06-01

    Because of the focal nature of stenoses or occlusions in the supra-aortic vasculature, the high blood-pressures in this area and the very low morbidity rates related to percutaneous therapy have largely replaced surgical revascularization as the initial treatment of choice for patients with supra-aortic arterial occlusive disease. The initial technical success and durability of percutaneous angioplasty (PTA) and stenting in these lesions is excellent. Nevertheless several factors can make PTA and stenting a complex procedure that requires advanced endovascular skills for a successful outcome. Profound knowledge of surgical reconstruction techniques or extra-anatomic bypasses remains mandatory, as it is occasionally required for failure of endovascular techniques or if contraindications exist.

  3. No evidence for thrombophilia in patients with retinal venous occlusion

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine; Heegaard, Steffen; Hvas, Anne-Mette

    2016-01-01

    Retinal venous occlusion represents a common retinal disorder that untreated often leads to severely reduced vision. While general risk factors for vascular disease are known to increase the risk of an event, the role of thrombophilia is controversial. The purpose of this systematic review...... was to evaluate the evidence for thrombophilia investigation in patients presenting with retinal venous occlusion. Eligible studies were identified by a MESH-based search in PubMed 11–13 of March 2015. The level of evidence was stated according to the guidelines published by the GRADE working group using three...... synthesis. The majority of studies were small case–control studies, and only one large cohort study was identified. No randomized controlled trials were retrieved. All the studies were categorized as low quality of evidence. Systematic thrombophilia screening in patients presenting with retinal venous...

  4. Vascular endothelial growth factor blocking agents in retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Chris Canning

    2008-01-01

    Full Text Available This paper summarises the current status of the use of vascular endothelial growth factor (VEGF blocking agents in retinal vein occlusion. There have been no randomised controlled trials comparing this treatment with the current standard treatment (largely laser so the lower grade evidence of single treatment case series and anecdotal reports are discussed. VEGF blockers are good at reducing macular oedema in the short term, do improve visual acuity in many cases, and do not seem to adversely affect the long term revascularisation that is necessary to overcome the vein occlusion. VEGF blocking agents are not used in isolation in this condition - they will remain an adjunct to systemic and other local treatments. The literature was reviewed in online searches of Embase and Ovid and the papers quoted are a representative sample of a larger body of publications.

  5. Preliminary experience with dynamic MR projection angiography in the evaluation of cervicocranial steno-occlusive disease

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, S.G.; Haselhorst, R.; Bilecen, D.; Radue, E.W. [Section of Neuroradiology, Kantonsspital Basel (Switzerland); Lyrer, P.A. [Dept. of Neurology, Kantonsspital Basel (Switzerland); Seifritz, E. [Psychiatric University Hospital Basel (Switzerland); Bongartz, G. [Inst. for Diagnostic Radiology, Kantonsspital Basel (Switzerland); Scheffler, K. [Department of Diagnostic Radiology, University of Freiburg, Freiburg (Germany)

    2001-02-01

    The application of a contrast-enhanced, two-dimensional MR technique, which provides dynamic projection angiograms at a subsecond temporal frame rate for depiction of the cervical and intracranial arteries, was evaluated in three healthy volunteers and seven patients with various cervicocranial steno-occlusive diseases. Intra-arterial digital subtraction angiography (DSA) served as standard of reference for findings in the patients. Magnetic resonance projection angiography (MRPA) was performed on a standard 1.5-T clinical MR imaging system at intravenous injection of a single dose of contrast agent (0.1 mmol/kg GdDTPA-BMA). Sixty consecutive images of the cerebral circulation were acquired at a temporal frame rate of 900 ms per image in the coronal plane. The collateral flow and the perfusion of the compromised vessel territory were readily assessed by MPRA in patients with occlusion of the internal cerebral artery (ICA) or middle cerebral artery (MCA). The leptomeningeal collateralisation of these patients was displayed in a dynamic fashion. Furthermore, quantitative perfusion measurement provided a difference between both MCA territories in the time to peak ({delta}DTTP) of the contrast bolus of 1.12 {+-} 0.28 s in five patients with severe stenosis or occlusion of the ICA (healthy volunteers 0.19 {+-} 0.05 s). However, important pathological findings, such as the evaluation of carotid artery stenoses and the intracranial collateral flow pattern in patients with severe carotid stenoses, were not sufficiently assessable as compared with DSA. We conclude that the possibility of obtaining simultaneously information about morphology and perfusion dynamics of the cervicocranial vessels is unique in MPRA as compared with other MR techniques. However, in the applied form, the technique is not a reliable tool for the complete evaluation of the cervicocranial vessels in patients with steno-occlusive disease. (orig.)

  6. Evolution of occlusal pathology. A literature review.

    Directory of Open Access Journals (Sweden)

    Camilo Guerrero

    2013-08-01

    Full Text Available Introduction: Many of the guidelines on occlusion and treatment alternatives in dentate and partially edentulous patients, are based on concepts raised in the beginning of dentistry. The diversity of the occlusion schools has become some of these concepts complex to understand and apply. This diversity makes difficult the compression of the occlusal physiology and its disorders, hindering the understanding of the occlusal pathology and its proper diagnosis and management. Objective: This is why we conducted a literature review about oclusal physiology and pathology, in order to gather information based on scientific evidence, which in order to clarify concepts and homogenize knowledge about physiological and morphological changesof thestomatognathic system, associated toocclusal alterations, allowing the future standardization of the occlusal diagnostic process at the Faculty of Dentistry of the National University of Colombia. Methodology: A search was conducted inMedLine, PubMed, Ovid, Ebsco, ScienceDirect and Hinari-Healthinternetwork using the Mesh terms: "Dental Occlusion" - "Stomatognathic System" - "masticatory System" - Temporomandibular Joint and the bibliographies of papers and review articles that had direct relationship to the topic; the publication deadline was not taken into account. In total, 79 articles, 10 texts and 7 websites were obtained. Conclusion: Occlusal pathology is an evolutionary process that might affect the form and/or function of any of the components of the stomatognathic system. Occlusal Harmony is a state in which each part of the system works in concert with the others to fulfill the functions of mastication, speech and swallowing; oral rehabilitation should be directed toward obtaining a harmonious occlusion.

  7. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  8. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  9. 2013 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  10. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  11. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  12. 2011 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  13. 2011 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  14. 2011 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  15. 2011 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  16. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  17. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  18. Blood Vessels in Allotransplantation

    National Research Council Canada - National Science Library

    Abrahimi, P; Liu, R; Pober, J. S

    2015-01-01

    Pober and colleagues present an overview of the various roles played by graft blood vessels in transplantation, including how they function to maintain graft health, how they participate in and are...

  19. Maury Journals - US Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  20. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. Coastal Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels that have been issued a Federal permit for the Gulf of Mexico reef fish,...

  2. Retinal occlusive vasculer disorder and rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Huseyin Ortak

    2013-03-01

    Full Text Available Rheumatoid arthritis is a systemic inflammatory disease that affected older women with many ocular manifestations. Also, these systemic diseases can cause retinal vein occlusion and arterial occlusion that lead to serious and permanent visual loss. Rheumatoid arthritis's the most common manifestation is that retinal vasculitis and retinal vascular complications are associated with this complication. In this review, retinal vascular occlusive diseases are presented to associated with rheumatoid arthritis in literature. Rheumatoid arthritis and its complications have been outlined and was made to create a new perspective. [J Contemp Med 2013; 3(1.000: 71-73

  3. Blood Vessel Tension Tester

    Science.gov (United States)

    1978-01-01

    In the photo, a medical researcher is using a specially designed laboratory apparatus for measuring blood vessel tension. It was designed by Langley Research Center as a service to researchers of Norfolk General Hospital and Eastern Virginia Medical School, Norfolk, Virginia. The investigators are studying how vascular smooth muscle-muscle in the walls of blood vessels-reacts to various stimulants, such as coffee, tea, alcohol or drugs. They sought help from Langley Research Center in devising a method of measuring the tension in blood vessel segments subjected to various stimuli. The task was complicated by the extremely small size of the specimens to be tested, blood vessel "loops" resembling small rubber bands, some only half a millimeter in diameter. Langley's Instrumentation Development Section responded with a miniaturized system whose key components are a "micropositioner" for stretching a length of blood vessel and a strain gage for measuring the smooth muscle tension developed. The micropositioner is a two-pronged holder. The loop of Mood vessel is hooked over the prongs and it is stretched by increasing the distance between the prongs in minute increments, fractions of a millimeter. At each increase, the tension developed is carefully measured. In some experiments, the holder and specimen are lowered into the test tubes shown, which contain a saline solution simulating body fluid; the effect of the compound on developed tension is then measured. The device has functioned well and the investigators say it has saved several months research time.

  4. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  5. Concurrent central retinal artery occlusion and branch retinal vein occlusion in giant cell arteritis

    OpenAIRE

    Chu, Edward R.; Chen, Celia S

    2010-01-01

    Edward R Chu, Celia S ChenDepartment of Ophthalmology, Flinders Medical Centre and Flinders University, Bedford Park, SA, AustraliaAbstract: Ophthalmic involvement in giant cell arteritis can manifest in a number of ways. Central retinal artery occlusion is one of the common causes of visual loss in giant cell arteritis. On the contrary, branch retinal vein occlusion is rarely associated with the latter. We report an 89-year-old lady with acute left central retinal artery occlusion on a backg...

  6. Examination of tissue oxygen saturation (StO2) changes associated with vascular pedicle occlusion in a rat Island flap model using near-Infrared spectroscopy.

    Science.gov (United States)

    Kagaya, Yu; Ohura, Norihiko; Kurita, Masakazu; Takushima, Akihiko; Harii, Kiyonori

    2015-07-01

    The purpose of this study was to perform continuous StO(2) monitoring of rat island flaps during pedicle vessel occlusion using near-infrared spectroscopy (NIRS) in order to collect experimental data for StO(2) flap monitoring under optimized conditions. Twenty rats were used in this study. The 3 × 3 cm(2) epigastric skin island flaps were elevated on either side. The animals were randomly assigned to two groups; an arterial occlusion group (n = 10) and a venous occlusion group (n = 10). The StO(2) values of the flaps were observed for over 30 min for the pedicle artery or venous occlusion, followed by an additional 30 min release. The baseline StO(2) value was 78.4% ± 3.2% in the arterial occlusion group, compared to 78.5% ± 5.8% in the venous occlusion group, with no significant differences (P > 0.05). The StO(2) values decreased immediately after arterial occlusion, whereas a temporal StO(2) increase was initially observed after venous occlusion, followed by a StO(2) decrease. The StO(2) values decreased 27.3% ± 7.1% after arterial occlusion and 28.4% ± 19.1% after venous occlusion at 30 min after pedicle vessel clamping (P > 0.05). The StO(2) values were 0.4% ± 5.8% lower than baseline 30 min after arterial release (P > 0.05), while 18.9% ± 11.3% lower than baseline 30 min after venous release (P StO(2) changes in flaps with the pedicle vessel occlusion and differentiate between pedicle artery and vein occlusion. Further investigations are needed to obtain definitive evidence associated with predicting the degree of flap viability and determine the practical use of this technique. © 2015 Wiley Periodicals, Inc.

  7. Pulmonary veno-occlusive disease.

    Science.gov (United States)

    Montani, David; Lau, Edmund M; Dorfmüller, Peter; Girerd, Barbara; Jaïs, Xavier; Savale, Laurent; Perros, Frederic; Nossent, Esther; Garcia, Gilles; Parent, Florence; Fadel, Elie; Soubrier, Florent; Sitbon, Olivier; Simonneau, Gérald; Humbert, Marc

    2016-05-01

    Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension (PH) characterised by preferential remodelling of the pulmonary venules. In the current PH classification, PVOD and pulmonary capillary haemangiomatosis (PCH) are considered to be a common entity and represent varied expressions of the same disease. The recent discovery of biallelic mutations in the EIF2AK4 gene as the cause of heritable PVOD/PCH represents a major milestone in our understanding of the molecular pathogenesis of PVOD. Although PVOD and pulmonary arterial hypertension (PAH) share a similar clinical presentation, with features of severe precapillary PH, it is important to differentiate these two conditions as PVOD carries a worse prognosis and life-threatening pulmonary oedema may occur following the initiation of PAH therapy. An accurate diagnosis of PVOD based on noninvasive investigations is possible utilising oxygen parameters, low diffusing capacity for carbon monoxide and characteristic signs on high-resolution computed tomography of the chest. No evidence-based medical therapy exists for PVOD at present and lung transplantation remains the preferred definitive therapy for eligible patients.

  8. Occlusive extracranial cerebrovascular disease: diagnosis and ...

    African Journals Online (AJOL)

    artery which then divides into the posterior cerebral arteries that supply the occipital ... In a review focusing on the causes of ... is a consequence of stenosis and occlusion involving all four ... as ischaemic heart disease, hypertension, diabetes ...

  9. Principles of occlusion in implant dentistry

    Directory of Open Access Journals (Sweden)

    Mahesh Verma

    2015-01-01

    Full Text Available Dental implants require different biomechanical considerations from natural teeth. Also, with one of the criteria for long-term implant success being “occlusion,” it becomes imperative for the clinician to be well versed with the different concepts when rehabilitating with an implant prosthesis. All endeavors must be made to reduce the overload and noxious forces on implants during mandibular movements. The occlusal rehabilitation schemes for implant-supported prostheses are derivatives of the occlusal scheme for natural dentition. The implant-protected occlusion (IPO scheme has been designed to ensure the longevity of both prosthesis and implant. The article reviews the concepts of IPO and their applicability in different clinical scenarios.

  10. Smile line and occlusion: An epidemiological study

    Directory of Open Access Journals (Sweden)

    Mahsa Harati

    2013-01-01

    Conclusion: Within the limitations of such studies, it might be concluded that there is a significant and important relation between some occlusal parameters and smile design, which must be considered.

  11. [Supra-aortic trunks occlusive disease: three different treatment approaches].

    Science.gov (United States)

    Dias, P; Almeida, P; Sampaio, S; Silva, A; Leite-Moreira, A; Pinho, P; Roncon de Albuquerque, R

    2010-01-01

    Unlike carotid bifurcation atherosclerotic stenosis, supra-aortic trunks (SAT) occlusive disease is rare and its revascularization uncommon, accouting for less than 10% of the operations performed on the extracranial brain-irrigating arteries. There are three different treatment approaches: transthoracic, extra-anatomic cervical and endovascular. Endovascular repair is gaining popularity as first-line therapy for proximal lesions with favorable anatomy because of its low morbidity and rare mortality. Extra-anatomic bypass is a safe and durable reconstruction and should be considered in patients with single vessel disease, with cardiopulmonary high-risk or with limited life expectancy. If cardiac surgery is needed, central transthoracic reconstruction is preferable, and the two procedures should be combined. The long-term patency of bypasses with aortic origin, specially when multiple vessels are involved, is superior to other repair techniques. We present three clinical cases that illustrate each of these therapeutic strategies: central brachiocephalic revascularization and synchronous cardiac surgery in a patient with complex SAT atherosclerosis disease; subclavian-carotid transposition for disabling upper limb claudication; and subclavian artery stenting for subclavian-steal syndrome. Surgical approach selection should be based on the individual patient's anatomy and operative risk.

  12. The Heart and Great Vessels.

    Science.gov (United States)

    Onwuka, Ekene; King, Nakesha; Heuer, Eric; Breuer, Christopher

    2017-03-13

    Cardiovascular disease is the leading cause of mortality worldwide. We have made large strides over the past few decades in management, but definitive therapeutic options to address this health-care burden are still limited. Given the ever-increasing need, much effort has been spent creating engineered tissue to replaced diseased tissue. This article gives a general overview of this work as it pertains to the development of great vessels, myocardium, and heart valves. In each area, we focus on currently studied methods, limitations, and areas for future study. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  13. Branch retinal artery occlusion in Susac's syndrome

    Directory of Open Access Journals (Sweden)

    Ricardo Evangelista Marrocos de Aragão

    2015-02-01

    Full Text Available Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  14. Current possibilities in occlusal caries management

    Directory of Open Access Journals (Sweden)

    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.

  15. Surgical management of large and giant intracavernous and paraclinoid aneurysms

    Institute of Scientific and Technical Information of China (English)

    Xu Bai-nan; SUN Zheng-hui; JIANG Jin-li; WU Chen; ZHOU Ding-biao; YU Xin-guang; LI Bao-min

    2008-01-01

    Background Due to their location,large and giant intracavernous and paraclinoid aneurysms remain a challenge for vascular neurosurgeons.We identified characteristics.surgical indications and treatment strategies of large and giant intracavernous and paraclinoid aneurysms in 36 patients.Methods The pterional approach was routinely used.The cervical internal carotid artery was exposed for proximal control of parent vessel and retrograde suction decompression.Paraclinoid aneurysms were directly clipped,intracavernous pseudoaneurysm was repaired and the intracavernous aneurysms were trapped with extracranial-intracranial bypass of saphenous vein graft.Intraoperative electroencephaIogram (EEG) and somatosensory evoked potential (SSEP) monitoring were used to detect cerebral ischemia during the temporary occlusion of parent arteries.Microvascular Doppler ultrasonography was used to assess blood flow of the parent and branch vessels.Endoscopy was helpful particularly in dealing with internal carotid artery posterior wall aneurysms.Postoperative digital subtraction angiography (DSA) was performed in 33 of the 36 patients.Results Thirty-two paraclinoid aneurysms were directly clipped,1 intracavernous pseudoaneurysm was repaired and the other 3 intracavernous aneurysms were trapped with revascula rization.Except for two patients who died in the early postoperative stage,34 patients' follow-up was 6-65 months (mean 10 months)and a Glasgow Outcome Scale score of 4 to 5 at discharge.At the 6-month follow-up examination,Rankin Outcome Scale scores were 0 to 2 in 32 patients.EEG and SSEP monitoring changed in six patients.Twelve clips were readjusted when insufficient blood flow in parent and branch vessels was detected.Three posterior wall aneurysms were clipped.Conclusions Intracavernous aneurysms not amenable to endovascular treatment should be treated surgically and surgical treatment is the first option for paraclinoid aneurysms.The temporary parent vessel occlusion

  16. Epulis and pyogenic granuloma with occlusal interference

    Directory of Open Access Journals (Sweden)

    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.

  17. Effect of the in- and ex-vessel dual cooling on the retention of an internally heated melt pool in a hemispherical vessel

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, K.I.; Kim, B.S.; Kim, D.H. [Korea Atomic Energy Research Inst., Thermal Hydraulic Safety Research, Taejon (Korea, Republic of)

    2001-07-01

    A concept of in-vessel melt retention (IVMR) by in-vessel reflooding and/or reactor cavity flooding has been considered as one of severe accident management strategies and intensive researches to be performed worldwide. This paper provides some results of analytical investigations on the effect of both in- / ex-vessel cooling on the retention of an internally heated molten pool confined in a hemispherical vessel and the related thermal behavior of the vessel wall. For the present analysis, a scale-down reactor vessel for the KSNP reactor design of 1000 MWe (a large dry PWR) is utilized for a reactor vessel. Aluminum oxide melt simulant is also utilized for a real corium pool. An internal power density in the molten pool is determined by a simple scaling analysis that equates the heat flux on the the scale-down vessel wall to that estimated from KSNP. Well-known temperature-dependent boiling heat transfer curves are applied to the in- and ex-vessel cooling boundaries and radiative heat transfer has been only considered in the case of dry in-vessel. MELTPOOL, which is a computational fluid dynamics (CFD) code developed at KAERI, is applied to obtain the time-varying heat flux distribution from a molten pool and the vessel wall temperature distributions with angular positions along the vessel wall. In order to gain further insights on the effectiveness of in- and ex-vessel dual cooling on the in-vessel corium retention, four different boundary conditions has been considered: no water inside the vessel without ex-vessel cooling, water inside the vessel without ex-vessel cooling, no water inside the vessel with ex-vessel cooling, and water inside the vessel with ex-vessel cooling. (authors)

  18. The effectiveness of occlusal splints for sleep bruxism.

    Science.gov (United States)

    Jagger, Robert

    2008-01-01

    Searches were made using the Cochrane Oral Health Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, LILACS (Latin American & Caribbean Health Sciences Literature), Biblioteca Brasileira de Odontologia, and Dissertations, Theses and Abstracts. Hand searches were made of abstracts of particular importance to this review. Additional reports were identified from the reference lists of retrieved reports and from article reviews about treating sleep bruxism. There were no language restrictions. Randomised controlled trials (RCT) or quasi-RCT were chosen that compared splint therapy concurrently with no treatment, other occlusal appliances, or any other intervention in participants who had sleep bruxism. Data extraction was carried out independently and in duplicate. Validity assessment of the included trials was carried out at the same time as data extraction. Discrepancies were discussed and a third review author consulted. The author of the primary study was contacted when necessary. Thirty-two potentially relevant RCT were identified of which five were eventually included. In these, use of an occlusal splint was compared with palatal splint, mandibular advancement device, transcutaneous electric nerve stimulation, and no treatment. There was just one common outcome (arousal index) which was combined in a meta-analysis. No statistically significant difference between the occlusal splint and control groups were found in meta-analysis. There is not enough evidence to state that the occlusal splint is effective for treating sleep bruxism. Indication of its use is questionable with regard to sleep outcomes, but there may be some benefit with regard to tooth wear. This systematic review suggests the need for further investigation in more controlled RCT that pay attention to method of allocation, outcome assessment, large sample size, and sufficient duration of followup. The study design must be parallel in order to eliminate

  19. Relationship of Occlusal Schemes with the Occurrence of Temporomandibular Disorders

    OpenAIRE

    Dina H. Sugiaman; Laura S. Himawan; Sitti Fardaniah

    2013-01-01

    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 ca...

  20. Retinal artery occlusions in children.

    Science.gov (United States)

    Dharmasena, Aruna; Wallis, Simon

    2014-01-01

    The purpose of this study is to present a case of RAO in a 13 year old girl with a preceding history of hyperextension of the neck at her hairdressers for a long duration and use of her mobile phone handset resting it against the side of her neck presumably exerting some pressure on carotids during the same time. Materials and methods of this study was reported as case report and review of literature. A 13 year-old girl presented with the left supero-nasal scotoma due to an inferior temporal branch retinal artery occlusion (BRAO). She underwent extensive investigations and no underlying cause was discovered. She gave a history of cervical extension over a long period of time while having the hair coloured twice in the preceding week. She also mentioned that she was using her mobile phone more or less continuously during both these occasions keeping it against her neck. Given the above history it is possible that the pressure on the ipsilateral carotid arteries or the prolong neck extension may have been responsible for the formation of a platelet embolus resulting in the BRAO. In conclusion, although cerebro-vascular accidents due to 'beauty parlor stroke syndrome' (JAMA 269:2085-2086, 1993) have been reported previously it has not been reported in children to our knowledge. On the other hand, 'beauty parlor stroke syndrome' occurs due to a dissection of the vertebral arteries or due to mechanical compression of the vertebral arteries during the prolonged hyperextension of the neck. The central retinal artery originates from the internal carotid circulation and it is highly unlikely for an embolus to enter the retinal circulation from the vertebral arteries. Therefore, the authors favour the possibility that the compulsive use of a mobile phone exerting pressure on the carotid arteries for a long time may have led to the formation of an embolus and subsequent RAO in this case.

  1. Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report

    Directory of Open Access Journals (Sweden)

    De Cicco Vincenzo

    2012-09-01

    Full Text Available Abstract Introduction A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. Case presentation A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. Conclusions A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be

  2. Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report.

    Science.gov (United States)

    De Cicco, Vincenzo

    2012-09-03

    A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be useful in patients with asymmetric hemodynamics of cerebro

  3. 大型玻璃钢渔船帽型骨架剖面参数的力学分析%Mechanics Analysis for Section Parameters of Cap- shape Frames of Large FRP Fishing Vessels

    Institute of Scientific and Technical Information of China (English)

    蒋丰; 沈叔曾

    2000-01-01

    In this paper, the section parameters of the cap - shape frame of the large FRP fishing vessel is analyzed by elastic stability theory. Both two models of thin rectangle plates on compression and shear stability are established. The section parameter b/t1 and h/t are obtained in four cases that is the four combinations for two materials (1: 1FRP and 4:1 FRP) and two boundaries (all edges simply supported and all edges clamped). The ranges are from 18.0 to 26. 2 and from 28.7 to 44.2 respectively. The results provide theory basis for the optimal design of section parameters of the cap - shape frame and the revision of relevant standard.%本文对大型玻璃钢渔船帽型骨架剖面参数,进行了在不利受力情况下正交各向异性玻璃钢薄板稳定的力学分析,建立了骨架受力分析--受压区的矩形薄板压缩稳定和腹板的矩形薄板剪切稳定两种力学模型,解得这两种力学模型,在两种材料(1:1玻璃钢和4:1玻璃钢)与两种边界条件(四边简支和四边固支)组合的四种条件下,骨架剖面参数的b/t1和h/t的取值范围,它们依次为18.0~26.2和28.7~44.2。文中分析结果为帽型骨架剖面参数的优化设计和相关规范的修订提供了理论依据。

  4. Vascular and cardiac contractile reserve in the dog heart with chronic multiple coronary occlusions.

    Science.gov (United States)

    Schwarz, F; Flameng, W; Mack, B; Türschmann, W; Schaper, W

    1976-11-01

    Nineteen mongrel dogs survived chronic occlusion of the left circumflex and of the right coronary artery without infarction due to the timely development of a collateral circulation. Only 38 per cent of the conductance of the arteries before occlusion was restored by collateral vessels. In these animals and in 15 control dogs with normal coronary arteries myocardial contractility, contractility reserve, and myocardial blood flow were studied. The same was done in dogs with chronic coronary artery occlusion after aortocoronary bypass. Myocardial blood flow was determined woth the tracer microsphere technique. Contractility reserve was tested and defined as isovolumetric left ventricular pressure and dp/dt max with norepinephrine infusion and cross-clamping of the aorta. Contractile reserve was not significantly different between normal dogs and dogs with chronic coronary artery occlusion before and after aortocoronary bypass. Myocardial blood flow during control conditions was homogenously distributed in all three groups studied. The ratio of blood flow to the endocardium and the epicardium was not significantly different from inity. Coronary reserve was determined at peak reactive hyperemia following a 20 second period of coronary artery occlusion, with ongoing norepinephrine infusion. Under these conditions subendocardial fow in normal dogs rose by a factor of 7.9 while subepicardial flow increased 7.4 times. In dogs with chronic occlusion of two coronary arteries the increase of myocardial flow was nonnomogenous; subendocardial flow to areas supplied by a normal coronary artery rose by a factor of 7.0 while subepicardial flow increased 5.7 times control. Subendocardial collateral flow rose by a factor of 2.4 and subepicardial collateral flow increased 3.5 times control. In normal dogs norepinephrine alone did not result in maximal coronary flow but only 57 per cent thereof. Dogs with chronic coronary occlusion, however, required the entire coronary reserve in

  5. Transfemoral transcatheter aortic valve implantation in patients with small diseased peripheral vessels

    Energy Technology Data Exchange (ETDEWEB)

    Ruparelia, Neil [San Raffaele Scientific Institute, Milan (Italy); Imperial College, London (United Kingdom); Buzzatti, Nicola; Romano, Vittorio; Longoni, Matteo; Figini, Fillipo; Montorfano, Matteo; Kawamoto, Hiroyoshi; Miyazaki, Tadashi; Spagnolo, Pietro; Alfieri, Ottavio; Colombo, Antonio [San Raffaele Scientific Institute, Milan (Italy); Latib, Azeem, E-mail: info@emocolumbus.it [San Raffaele Scientific Institute, Milan (Italy)

    2015-09-15

    Objectives: The aim of this study was to assess the feasibility, safety and short-term outcomes of transfemoral transcatheter aortic valve implantation (TF-TAVI) in patients with small diseased peripheral vessels. Background: The transfemoral (TF) route for transcatheter aortic valve (TAVI) is the default option due to associated advantages. However, this is limited due to the high prevalence of significant peripheral arterial disease and increased risk of vascular complications. Methods: Of 539 consecutive patients undergoing TAVI in a single Italian center, 23 patients underwent TF-TAVI in the presence of small peripheral vessels as defined by a minimal luminal diameter (MLD) of ≤ 5.5 mm [by computed tomography (CT)] and/or the inability to advance a large-bore sheath. Calcification was defined as being concentric if calcium extended more than 270° around the circumference of the artery. All patients underwent 30-day clinical follow-up. Results: 17 (73.9%) patients underwent peripheral vessel pre-dilatation with a semi-compliant balloon and 6 (26.1%) patients with a Solopath sheath. 6 (26.1%) patients suffered a peri-procedural complication, with 1 patient requiring surgical embolectomy for thrombotic occlusion and the remaining patients successfully managed percutaneously in the catheter laboratory. No patient suffered a vessel perforation or required implantation of a covered stent. At 30-day follow-up, all patients were free of symptoms and signs or symptoms of peripheral vascular disease, with well-functioning TAVI prostheses as evaluated by echocardiography. Conclusions: Performing TF-TAVI is feasible in patients with no other viable vascular access option in the presence of small MLD and calcification of the peripheral vasculature, with any anticipated acute vascular complication managed in the catheter laboratory with established percutaneous techniques. - Highlights: • Small peripheral vessels is regarded as contraindication to transfemoral TAVI.

  6. Pressurized Vessel Slurry Pumping

    Energy Technology Data Exchange (ETDEWEB)

    Pound, C.R.

    2001-09-17

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air.

  7. Very Versatile Vessel

    Science.gov (United States)

    2009-09-01

    data. This source provides information on aluminum hydrofoil vessels without the added weight of foil structures. The composite armor around the...to Powerboats. New York: International Marine/Ragged Mountain P, 2002. 8. [Asset/ Hydrofoil Advanced Surface Ship Evaluation Tool Module User Manual

  8. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  9. Graywater Discharges from Vessels

    Science.gov (United States)

    2011-11-01

    addition, based on personal contact with the shipping company, storing graywater in ballast tanks while in port can limit vessel stability considering...enters the treatment system and mixes with the aerated liquid already in the aeration chamber. EPDM Air diffuser injects air near the bottom of the

  10. A survey of occlusion detection method for visual object

    Institute of Scientific and Technical Information of China (English)

    张世辉

    2016-01-01

    Occlusion problem is one of the challenging issues in vision field for a long time , and the occlu-sion phenomenon of visual object will be involved in many vision research fields .Once the occlusion occurs in a visual system , it will affect the effects of object recognition , tracking, observation and operation , so detecting occlusion autonomously should be one of the abilities for an intelligent vision system .The research on occlusion detection method for visual object has increasingly attracted atten-tions of scholars .First, the definition and classification of the occlusion problem are presented . Then, the characteristics and deficiencies of the occlusion detection methods based on the intensity image and the depth image are analyzed respectively , and the existing occlusion detection methods are compared.Finally, the problems of existing occlusion detection methods and possible research directions are pointed out .

  11. Occlusion issues in early Renaissance art

    Science.gov (United States)

    Gillam, Barbara

    2011-01-01

    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. PMID:23145262

  12. 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.

  13. The history of surgical treatment for occlusive carotid artery diseases

    Directory of Open Access Journals (Sweden)

    Ding-biao ZHOU

    2014-01-01

    Full Text Available In this article, the history of surgical treatment for occlusive carotid artery diseases is briefly reviewed. It is emphasized that, after the results of large cohort, multicenter, randomized clinical trials, including North American Symptomatic Carotid Endarterectomy Trial (NASCET and European Carotid Surgery Trial (ECST, were reported in 1991, the important role of carotid endarterectomy (CEA for the surgical treatment of carotid atherosclerosis had already been confirmed. Although it has a late start in China, CEA has a bright and promising future.

  14. Occlusion in implant dentistry. A review of the literature of prosthetic determinants and current concepts.

    Science.gov (United States)

    Gross, M D

    2008-06-01

    Today the clinician is faced with widely varying concepts regarding the number, location, distribution and inclination of implants required to support the functional and parafunctional demands of occlusal loading. Primary clinical dilemmas of planning for maximal or minimal numbers of implants, their axial inclination, lengths and required volume and quality of supporting bone remain largely unanswered by adequate clinical outcome research. Planning and executing optimal occlusion schemes is an integral part of implant supported restorations. In its wider sense this includes considerations of multiple inter-relating factors of ensuring adequate bone support, implant location number, length, distribution and inclination, splinting, vertical dimension aesthetics, static and dynamic occlusal schemes and more. Current concepts and research on occlusal loading and overloading are reviewed together with clinical outcome and biomechanical studies and their clinical relevance discussed. A comparison between teeth and implants regarding their proprioceptive properties and mechanisms of supporting functional and parafunctional loading is made and clinical applications made regarding current concepts in restoring the partially edentulous dentition. The relevance of occlusal traumatism and fatigue microdamage alone or in combination with periodontal or peri-implant inflammation is reviewed and applied to clinical considerations regarding splinting of adjacent implants and teeth, posterior support and eccentric guidance schemes. Occlusal restoration of the natural dentition has classically been divided into considerations of planning for sufficient posterior support, occlusal vertical dimension and eccentric guidance to provide comfort and aesthetics. Mutual protection and anterior disclusion have come to be considered as acceptable therapeutic modalities. These concepts have been transferred to the restoration of implant-supported restoration largely by default. However, in

  15. Intercalibration of research survey vessels on Lake Erie

    Science.gov (United States)

    Tyson, J.T.; Johnson, T.B.; Knight, C.T.; Bur, M.T.

    2006-01-01

    Fish abundance indices obtained from annual research trawl surveys are an integral part of fisheries stock assessment and management in the Great Lakes. It is difficult, however, to administer trawl surveys using a single vessel-gear combination owing to the large size of these systems, the jurisdictional boundaries that bisect the Great Lakes, and changes in vessels as a result of fleet replacement. When trawl surveys are administered by multiple vessel-gear combinations, systematic error may be introduced in combining catch-per-unit-effort (CPUE) data across vessels. This bias is associated with relative differences in catchability among vessel-gear combinations. In Lake Erie, five different research vessels conduct seasonal trawl surveys in the western half of the lake. To eliminate this systematic bias, the Lake Erie agencies conducted a side-by-side trawling experiment in 2003 to develop correction factors for CPUE data associated with different vessel-gear combinations. Correcting for systematic bias in CPUE data should lead to more accurate and comparable estimates of species density and biomass. We estimated correction factors for the 10 most commonly collected species age-groups for each vessel during the experiment. Most of the correction factors (70%) ranged from 0.5 to 2.0, indicating that the systematic bias associated with different vessel-gear combinations was not large. Differences in CPUE were most evident for vessels using different sampling gears, although significant differences also existed for vessels using the same gears. These results suggest that standardizing gear is important for multiple-vessel surveys, but there will still be significant differences in catchability stemming from the vessel effects and agencies must correct for this. With standardized estimates of CPUE, the Lake Erie agencies will have the ability to directly compare and combine time series for species abundance. ?? Copyright by the American Fisheries Society 2006.

  16. Occlusal splints for treating sleep bruxism (tooth grinding).

    Science.gov (United States)

    Macedo, C R; Silva, A B; Machado, M A; Saconato, H; Prado, G F

    2007-10-17

    Sleep bruxism is an oral activity characterised by teeth grinding or clenching during sleep. Several treatments for sleep bruxism have been proposed such as pharmacological, psychological, and dental. To evaluate the effectiveness of occlusal splints for the treatment of sleep bruxism with alternative interventions, placebo or no treatment. We searched the Cochrane Oral Health Group's Trials Register (to May 2007); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 1); MEDLINE (1966 to May 2007); EMBASE (1980 to May 2007); LILACS (1982 to May 2007); Biblioteca Brasileira de Odontologia (1982 to May 2007); Dissertation, Theses and Abstracts (1981 to May 2007); and handsearched abstracts of particular importance to this review. Additional reports were identified from the reference lists of retrieved reports and from article reviews about treating sleep bruxism. There were no language restrictions. We selected randomised or quasi-randomised controlled trials (RCTs), in which splint therapy was compared concurrently to no treatment, other occlusal appliances, or any other intervention in participants with sleep bruxism. Data extraction was carried out independently and in duplicate. Validity assessment of the included trials was carried out at the same time as data extraction. Discrepancies were discussed and a third review author consulted. The author of the primary study was contacted when necessary. Thirty-two potentially relevant RCTs were identified. Twenty-four trials were excluded. Five RCTs were included. Occlusal splint was compared to: palatal splint, mandibular advancement device, transcutaneous electric nerve stimulation, and no treatment. There was just one common outcome (arousal index) which was combined in a meta-analysis. No statistically significant differences between the occlusal splint and control groups were found in the meta-analyses. There is not sufficient evidence to state that the occlusal splint is

  17. 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...... of this study is to review the literature on the effects of glove occlusion on skin barrier function. The PubMed database was searched up to 1 February 2015 for articles on the association between glove occlusion and skin barrier function, including human studies only and in English. Only experimental studies...... by detergents/soaps in a dose-response fashion....

  18. Occlusal Caries: Biological Approach for Its Diagnosis and Management

    DEFF Research Database (Denmark)

    Carvalho, JC; Dige, Irene; Machiulskiene, V

    2016-01-01

    The management of occlusal caries still remains a major challenge for researchers as well as for general practitioners. The present paper reviews and discusses the most up-to-date knowledge and evidence of the biological principles guiding diagnosis, risk assessment, and management of the caries...... process on occlusal surfaces. In addition, it considers the whole spectrum of the caries process on occlusal surfaces, ranging from the molecular ecology of occlusal biofilms to the management of deep occlusal caries lesions. Studies using molecular methods with focus on biofilms in relation to occlusal...

  19. Posterior circulation revascularization to manage vertebrobasilar occlusion

    Directory of Open Access Journals (Sweden)

    SHANG Yan-guo

    2012-06-01

    Full Text Available Objective To discuss the technique and effect of posterior circulation revascularization to manage vertebrobasilar occlusion. Methods Nine patients with vertebrobasilar occlusion were treated by using occipital artery-posterior inferior cerebellar artery bypass, superficial temporal artery-superior cerebellar artery bypass, superficial temporal artery-posterior cerebral artery bypass and occipital artery-vertebral artery bypass with radial artery graft. Results Intraoperative indocyanine green angiography showed all the bypass arteries were patent. Postoperative DSA or CTA showed bypass arteries patent in 8 patients, among whom seven patients got obvious improvement on MR or CT perfusion. One patient died of heart failure on the 15th day postoperative. During the follow-up of eight patients, no stroke reoccurred, four patients got back to nearly normal life. Conclusion Most of the patients with vertebrobasilar occlusion could benefit from the posterior circulation revascularization, which should be confirmed by randomized controlled clinical trials in the future.

  20. 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).

  1. Sublingual Microvascular Changes in Patients With Cerebral Small Vessel Disease

    NARCIS (Netherlands)

    M. Khalilzada; K. Dogan; C. Ince; J. Stam

    2011-01-01

    Background and Purpose-It is unknown whether changes in cerebral small vessel disease (SVD) are limited to the brain or part of a generalized vascular disorder. Methods-We examined the sublingual microcirculation of 10 healthy controls, 10 patients with large vessel disease, and 8 with SVD, with sid

  2. 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.

  3. Occlusal Characteristics of the Primary Dentition Revisited.

    Science.gov (United States)

    Alexander, Stanley A; Askari, Marjan; Lewis, Patricia

    2015-11-01

    The occlusal characteristics of the primary dentition of 130 children 3 to 6 years old were examined. Variables were the terminal plane relationship, primary canine occlusion, spacing, overjet and overbite relationships. The flush terminal plane was the most common finding. A Class I relationship of the primary canine occurred in 85% of the subjects. Spaced dentitions occurred 81% of the time, while the presence of primate spaces occurred in at least one of the four quadrants. The overjet relationship varied from +1 mm to 4 mm in all subjects, and the majority of children were considered to have a normal overbite.

  4. Rationale and technique for achieving occlusal harmony.

    Science.gov (United States)

    Kimmel, Saul S

    2009-01-01

    For a patient to function normally with natural or restored dentition, the occlusal contacts should be in harmony with the musculature and the temporomandibular joint. Many times, this harmonious relationship is altered by restorative treatment, periodontal disease or tooth loss. If the adaptive capacity of the patient is less than the forces placed upon the tooth or restoration, failure in one form or another often results. This article presents a rational method the dentist can use to recognize and understand the markings made with articulating paper so that harmonious contacts can be detected and contacts that disturb occlusal harmony eliminated.

  5. Preliminary results on nonparametric facial occlusion detection

    Directory of Open Access Journals (Sweden)

    Daniel LÓPEZ SÁNCHEZ

    2016-10-01

    Full Text Available The problem of face recognition has been extensively studied in the available literature, however, some aspects of this field require further research. The design and implementation of face recognition systems that can efficiently handle unconstrained conditions (e.g. pose variations, illumination, partial occlusion... is still an area under active research. This work focuses on the design of a new nonparametric occlusion detection technique. In addition, we present some preliminary results that indicate that the proposed technique might be useful to face recognition systems, allowing them to dynamically discard occluded face parts.

  6. For-Hire Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Directory is maintained as the sample frame for the For-Hire Survey. I contains data on for-hire vessels on the Atlantic and Gulf coasts. Data include...

  7. American Samoa Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for American Samoa. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  8. CNMI Abandoned Vessel Inventory, Tinian

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Tinian. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  9. Hawaii Abandoned Vessel Inventory, Oahu

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Oahu, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  10. Puerto Rico Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Puerto Rico. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  11. Hawaii Abandoned Vessel Inventory, Maui

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Maui. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  12. CNMI Abandoned Vessel Inventory, Rota

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Rota. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  13. CNMI Abandoned Vessel Inventory, Saipan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Saipan. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  14. Hawaii Abandoned Vessel Inventory, Kauai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Kauai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  15. Hawaii Abandoned Vessel Inventory, Molokai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Molokai, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  16. Vessels in Transit - Web Tool

    Data.gov (United States)

    Department of Transportation — A web tool that provides real-time information on vessels transiting the Saint Lawrence Seaway. Visitors may sort by order of turn, vessel name, or last location in...

  17. Hawaii Abandoned Vessel Inventory, Lanai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Lanai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  18. Real-time beyond the horizon vessel detection

    Science.gov (United States)

    Roarty, Hugh J.; Smith, Michael; Glenn, Scott M.; Barrick, Donald E.

    2013-05-01

    The marine transportation system (MTS) is a vital component of the United States Economy. Waterborne cargo accounts for more than $742 billion of the nation's economy and creates employment for 13 million citizens. A disruption in this system would have far reaching consequences to the security of the country. The US National High Frequency radar network, which comprises 130 radar stations around the country, became operational in May 2009. It provides hourly measurements of surface currents to the US Coast Guard for search and rescue (SAR). This system has the capability of being a dual use system providing information for environmental monitoring as well as vessel position information for maritime security. Real time vessel detection has been implemented at two of the radar stations outside New York Harbor. Several experiments were conducted to see the amount vessel traffic that the radar could capture. The radars were able to detect a majority of the vessels that are reporting via the Automatic Identification System (AIS) as well as 30 percent of mid to large size vessels that are not reporting via AIS. The radars were able to detect vessels out to 60 km from the coast. The addition of a vessel detection capability to the National HF radar network will provide valuable information to maritime security sector. This dual use capability will fill a gap in the current surveillance of US coastal waters. It will also provide longer-range situational awareness necessary to detect and track smaller size vessels in the large vessel clutter.

  19. The location of obstruction predicts stent occlusion in malignant gastric outlet obstruction

    Science.gov (United States)

    Grunwald, Douglas; Cohen, Jonah; Bartley, Anthony; Sheridan, Jennifer; Chuttani, Ram; Sawhney, Mandeep S.; Pleskow, Douglas K.; Berzin, Tyler M.; Mizrahi, Meir

    2016-01-01

    Background: Gastric outlet obstruction (GOO) can occur with locally invasive or metastatic cancer involving the upper gastrointestinal tract at the pylorus or the duodenum. Endoscopic management with self-expanding metal stents (SEMSs) is often the preferred palliative approach. Stent occlusion is a common reason for failure and reintervention. We set out to determine whether the location of the malignant obstruction is associated with the angulation of the stent and can predict stent occlusion. Methods: We performed a retrospective review of consecutive patients who underwent successful duodenal stenting with SEMS for malignant GOO between 2006 and 2015 at a large advanced endoscopy referral center. We determined the location of obstruction, the stent angle, and the rate of technical and clinical success of stent placement. We then identified cases of subsequent stent occlusion confirmed by endoscopic evaluation. Results: A total of 100 consecutive patients were included in the study; 91 of these patients had enough data to evaluate SEMS occlusion. A total of 21 patients (23%) developed stent occlusion with a median time of 39 days. The risk of occlusion sequentially increased as the obstruction occurred more distally from the antrum to the third or fourth portion of the duodenum (p = 0.006). This relationship was maintained after controlling for stent angle (p = 0.05). Conclusions: A distal location of malignant GOO was strongly predictive of stent occlusion, independent of stent angle. This may be due to longer and more complex distal obstructions, along with foreshortening of the stent during placement and tumor infiltration. If replicated, these results will have implications for endoscopic practice and future device development. PMID:27803736

  20. Occlusion, prosthodontic treatment, and temporomandibular disorders: a review.

    Science.gov (United States)

    Hagag, G; Yoshida, K; Miura, H

    2000-03-01

    The purpose of this article is to review the literature on the relationship between occlusal discrepancies and temporomandibular disorders (TMD) and to summarize the guidelines of treating TMD by prosthetic rehabilitation. To date, the relationship between occlusal condition and TMD has not been confirmed, although there is a current trend toward making a weak correlation between occlusal interference and TMD. Furthermore, several types of occlusal discrepancies have been considered as variable features of the norm. But unstable occlusion in the intercuspal position may cause TMD. In cases of restored dentition, the problem is probably different and iatrogenic TMD are not rare. Namely, malformed occlusal surfaces, defects in anterior guidance, occlusal curvature, and vertical dimension may lead to some TMD trouble. According to these recent concepts the treatment modalities of TMD have been changed. Conservative treatments such as counseling, behavioral modification, physical therapy, pharmacotherapy, and interocclusal appliances should be the first choice, and treatments that lead to drastic changes of occlusion are not recommended.

  1. Comparative evaluation of the efficacy of occlusal splints fabricated in centric relation or maximum intercuspation in temporomandibular disorders patients

    Directory of Open Access Journals (Sweden)

    Marcelo Matida Hamata

    2009-02-01

    Full Text Available Fabrication of occlusal splints in centric relation for temporomandibular disorders (TMD patients is arguable, since this position has been defined for asymptomatic stomatognathic system. Thus, maximum intercuspation might be employed in patients with occlusal stability, eliminating the need for interocclusal records. This study compared occlusal splints fabricated in centric relation and maximum intercuspation in muscle pain reduction of TMD patients. Twenty patients with TMD of myogenous origin and bruxism were divided into 2 groups treated with splints in maximum intercuspation (I or centric relation (II. Clinical, electrognathographic and electromyographic examinations were performed before and 3 months after therapy. Data were analyzed by the Student's t test. Differences at 5% level of probability were considered statistically significant. There was a remarkable reduction in pain symptomatology, without statistically significant differences (p>0.05 between the groups. There was mandibular repositioning during therapy, as demonstrated by the change in occlusal contacts on the splints. Electrognathographic examination demonstrated a significant increase in maximum left lateral movement for group I and right lateral movement for group II (p0.05 in the electromyographic activities at rest after utilization of both splints. In conclusion, both occlusal splints were effective for pain control and presented similar action. The results suggest that maximum intercuspation may be used for fabrication of occlusal splints in patients with occlusal stability without large discrepancies between centric relation and maximum intercuspation. Moreover, this technique is simpler and less expensive.

  2. Crossing Total Occlusions: Navigating Towards Recanalization

    NARCIS (Netherlands)

    A. Sakes (Aimée); E.S. Regar (Eveline); J. Dankelman (Jenny); P. Breedveld (Paul)

    2016-01-01

    textabstractChronic total occlusions (CTOs) represent the “last frontier” of percutaneous interventions. The main technical challenges lies in crossing the guidewire into the distal true lumen, which is primarily due to three problems: device buckling during initial puncture, inadequate visualizatio

  3. Crossing Total Occlusions: Navigating Towards Recanalization

    NARCIS (Netherlands)

    Sakes, A.; Regar, E.; Dankelman, J; Breedveld, P.

    2016-01-01

    Chronic total occlusions (CTOs) represent the “last frontier” of percutaneous interventions. The main technical challenges lies in crossing the guidewire into the distal true lumen, which is primarily due to three problems: device buckling during initial puncture, inadequate visualization, and the i

  4. Class II malocclusion occlusal severity description

    Directory of Open Access Journals (Sweden)

    Guilherme Janson

    2010-08-01

    Full Text Available OBJECTIVES: It is well known that the efficacy and the efficiency of a Class II malocclusion treatment are aspects closely related to the severity of the dental anteroposterior discrepancy. Even though, sample selection based on cephalometric variables without considering the severity of the occlusal anteroposterior discrepancy is still common in current papers. In some of them, when occlusal parameters are chosen, the severity is often neglected. The purpose of this study is to verify the importance given to the classification of Class II malocclusion, based on the criteria used for sample selection in a great number of papers published in the orthodontic journal with the highest impact factor. MATERIAL AND METHODS: A search was performed in PubMed database for full-text research papers referencing Class II malocclusion in the history of the American Journal of Orthodontics and Dentofacial Orthopedics (AJO-DO. RESULTS: A total of 359 papers were retrieved, among which only 72 (20.06% papers described the occlusal severity of the Class II malocclusion sample. In the other 287 (79.94% papers that did not specify the anteroposterior discrepancy severity, description was considered to be crucial in 159 (55.40% of them. CONCLUSIONS: Omission in describing the occlusal severity demands a cautious interpretation of 44.29% of the papers retrieved in this study.

  5. Clinical Practice Guidelines for intestinal occlusion.

    Directory of Open Access Journals (Sweden)

    Rudis Miguel Monzón Rodríguez

    2009-03-01

    Full Text Available Clinical Practice Guidelines for intestinal occlusion. This document includes the main aspects related with classification, physiopathology, clinical diagnosis, complementary examinations and therapy aimed at the post-operatory treatment. It includes assessment guidelines focused on the most important aspects to be accomplished.

  6. Virtual occlusion in planning orthognathic surgical procedures.

    NARCIS (Netherlands)

    Nadjmi, N.; Mollemans, W.; Daelemans, A.; Hemelen, G. Van; Schutyser, F.A.C.; Berge, S.J.

    2010-01-01

    Accurate preoperative planning is mandatory for orthognathic surgery. One of the most important aims of this planning process is obtaining good postoperative dental occlusion. Recently, 3D image-based planning systems have been introduced that enable a surgeon to define different osteotomy planes pr

  7. Cilioretinal artery occlusion following intranasal cocaine insufflations

    Directory of Open Access Journals (Sweden)

    Balaji Kannan

    2011-01-01

    Full Text Available Cocaine is used to produce a euphoric effect by abusers, who may be unaware of the devastating systemic and ocular side effects of this drug. We describe the first known case of cilioretinal artery occlusion after intranasal cocaine abuse.

  8. Virtual occlusal definition for orthognathic surgery.

    Science.gov (United States)

    Liu, X J; Li, Q Q; Zhang, Z; Li, T T; Xie, Z; Zhang, Y

    2016-03-01

    Computer-assisted surgical simulation is being used increasingly in orthognathic surgery. However, occlusal definition is still undertaken using model surgery with subsequent digitization via surface scanning or cone beam computed tomography. A software tool has been developed and a workflow set up in order to achieve a virtual occlusal definition. The results of a validation study carried out on 60 models of normal occlusion are presented. Inter- and intra-user correlation tests were used to investigate the reproducibility of the manual setting point procedure. The errors between the virtually set positions (test) and the digitized manually set positions (gold standard) were compared. The consistency in virtual set positions performed by three individual users was investigated by one way analysis of variance test. Inter- and intra-observer correlation coefficients for manual setting points were all greater than 0.95. Overall, the median error between the test and the gold standard positions was 1.06mm. Errors did not differ among teeth (F=0.371, P>0.05). The errors were not significantly different from 1mm (P>0.05). There were no significant differences in the errors made by the three independent users (P>0.05). In conclusion, this workflow for virtual occlusal definition was found to be reliable and accurate.

  9. Crossing Total Occlusions: Navigating Towards Recanalization

    NARCIS (Netherlands)

    Sakes, A.; Regar, E.; Dankelman, J; Breedveld, P.

    2016-01-01

    Chronic total occlusions (CTOs) represent the “last frontier” of percutaneous interventions. The main technical challenges lies in crossing the guidewire into the distal true lumen, which is primarily due to three problems: device buckling during initial puncture, inadequate visualization, and the i

  10. Crossing Total Occlusions: Navigating Towards Recanalization

    NARCIS (Netherlands)

    A. Sakes (Aimée); E.S. Regar (Eveline); J. Dankelman (Jenny); P. Breedveld (Paul)

    2016-01-01

    textabstractChronic total occlusions (CTOs) represent the “last frontier” of percutaneous interventions. The main technical challenges lies in crossing the guidewire into the distal true lumen, which is primarily due to three problems: device buckling during initial puncture, inadequate visualizatio

  11. Arterial occlusion precipitated by cisplatinbased chemotherapy

    OpenAIRE

    2010-01-01

    Cisplatin-based therapy is curative in testicular cancer. Adverse effects of cisplatin-based chemotherapy include dose-dependent myelosuppression, nephrotoxicity, neurotoxicity, and ototoxicity. By contrast, chemotherapy-associated vascular complications are unpredictable. Few incidents of digital gangrene with cisplatin have been reported. Here, we present a patient who developed arterial occlusion leading to gangrene of the toe after cisplatinbased chemotherapy.

  12. 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

  13. Longitudinal occlusal changes from primary to permanent dentition in children with normal primary occlusion.

    Science.gov (United States)

    Legovic, M; Mady, L

    1999-06-01

    This purpose of this research was to examine the stability of normal occlusion during the transition from primary to permanent dentition. The sample consisted of 128 children (83 boys and 45 girls) 4.5 to 5.5 years old with normal occlusion in the primary dentition. The subjects were reexamined at 12.5 to 13.5 years. None had received orthodontic treatment. Although all the subjects had normal occlusion in the primary dentition, 72.7% (73.5% boys and 71.1% girls) had developed anomalies following eruption of the permanent teeth. These anomalies included crowding, Class II Division 1 or Class II Division 2 malocclusion, mesial occlusion complex, lateral crossbite, anterior crossbite, premature tooth loss, openbite or other anomalies.

  14. Over-expression of Slit2 induces vessel formation and changes blood vessel permeability in mouse brain

    Institute of Scientific and Technical Information of China (English)

    Hai-xiong HAN; Jian-guo GENG

    2011-01-01

    Aim:To investigate the effect of the axon guidance cue Slit2 on the density of blood vessels and permeability of the blood-brain barrier in mouse brain.Methods:hSlit2 transgenic mouse line was constructed,and the phenotypes of the mice were compared with wild-type mice in respect to the lateral ventricle (LV),ventricle pressure,and the choroids plexus.An in vivo Miles permeability assay and an amyloid-β permeability assay were used to assess the permeability of brain blood vessels.Brain vessel casting and intracerebral hemorrhage models were built to investigate vessel density in the transgenic mice.An in vitro permeability assay was used to test whether Slit2 could change the permeability and tight junctions of blood vessel endothelial cells.Results:Hydrocephalus occurred in some transgenic mice,and a significantly larger lateral ventricle area and significantly higher ventricle pressure were observed in the transgenic mice.The transgenic mice displayed changed construction of the choroids plexus,which had more micro vessels,dilated vessels,gaps between epithelial cells and endothelial cells than wild-type mice.Slit2 significantly increased brain vessel density and the permeability of brain vessels to large molecules.These blood vessels were more sensitive to cues that induce brain hemorrhage.At the cellular level,Slit2 disturbed the integrity of tight junctions in blood vessel endothelial cells and improved the permeability of the endothelial cell layer.Thus,it promoted the entry of amyloid-β peptides from the serum into the central nervous system,where they bound to neurons.Conclusion:Slit2 increases vessel density and permeability in the brains of transgenic mice.Thus,Slit2 induces numerous changes in brain vessels and the barrier system.

  15. Risk factors for vascular occlusive events and death due to bleeding in trauma patients; an analysis of the CRASH-2 cohort.

    Directory of Open Access Journals (Sweden)

    Louise Pealing

    Full Text Available Vascular occlusive events can complicate recovery following trauma. We examined risk factors for venous and arterial vascular occlusive events in trauma patients and the extent to which the risk of vascular occlusive events varies with the severity of bleeding.We conducted a cohort analysis using data from a large international, double-blind, randomised, placebo-controlled trial (The CRASH-2 trial [1]. We studied the association between patient demographic and physiological parameters at hospital admission and the risk of vascular occlusive events. To assess the extent to which risk of vascular occlusive events varies with severity of bleeding, we constructed a prognostic model for the risk of death due to bleeding and assessed the relationship between risk of death due to bleeding and risk of vascular occlusive events. There were 20,127 trauma patients with outcome data including 204 (1.01% patients with a venous event (pulmonary embolism or deep vein thrombosis and 200 (0.99% with an arterial event (myocardial infarction or stroke. There were 81 deaths due to vascular occlusive events. Increasing age, decreasing systolic blood pressure, increased respiratory rates, longer central capillary refill times, higher heart rates and lower Glasgow Coma Scores (all p<0.02 were strong risk factors for venous and arterial vascular occlusive events. Patients with more severe bleeding as assessed by predicted risk of haemorrhage death had a greatly increased risk for all types of vascular occlusive event (all p<0.001.Patients with severe traumatic bleeding are at greatly increased risk of venous and arterial vascular occlusive events. Older age and blunt trauma are also risk factors for vascular occlusive events. Effective treatment of bleeding may reduce venous and arterial vascular occlusive complications in trauma patients.

  16. An appraisal on increasing the occlusal vertical dimension in full occlusal rehabilitation and its outcome.

    Science.gov (United States)

    Gopi Chander, N; Venkat, R

    2011-06-01

    Increasing the occlusal vertical dimension for gaining sufficient restoration space in the management of severely worn dentition is being practiced. This contentious belief has lead to challenging thoughts regarding its effects on the Odonto-stomatognathic system. There are basic uncertainties and existing erroneous thoughts regarding the perception of increasing the occlusal vertical dimension. This manuscript will review the bite raising concepts and its outcome on the stomatognathic system.

  17. An Appraisal on Increasing the Occlusal Vertical Dimension in Full Occlusal Rehabilitation and its Outcome

    OpenAIRE

    2011-01-01

    Increasing the occlusal vertical dimension for gaining sufficient restoration space in the management of severely worn dentition is being practiced. This contentious belief has lead to challenging thoughts regarding its effects on the Odonto-stomatognathic system. There are basic uncertainties and existing erroneous thoughts regarding the perception of increasing the occlusal vertical dimension. This manuscript will review the bite raising concepts and its outcome on the stomatognathic system.

  18. 46 CFR 171.050 - Intact stability requirements for a mechanically propelled or a nonself-propelled vessel.

    Science.gov (United States)

    2010-10-01

    ... propelled or a nonself-propelled vessel. 171.050 Section 171.050 Shipping COAST GUARD, DEPARTMENT OF... PASSENGERS Large Vessels § 171.050 Intact stability requirements for a mechanically propelled or a nonself-propelled vessel. Each vessel must be shown by design calculations to have a metacentric height (GM) in...

  19. Central Retinal Artery Occlusion With Subsequent Central Retinal Vein Occlusion in Biopsy-Proven Giant Cell Arteritis.

    Science.gov (United States)

    Williams, Zoë R; Wang, Xiaofei; DiLoreto, David A

    2016-09-01

    Central retinal artery occlusion with subsequent central retinal vein occlusion in the same eye is a rare entity. We present a 72-year-old man with biopsy-proven giant cell arteritis who developed bilateral arteritic anterior ischemic optic neuropathy and a left central retinal artery occlusion. Subsequently, he developed a left central retinal vein occlusion within 2 weeks of his initial vision loss. His vision did not improve with corticosteroids.

  20. Gulf of Mexico Marine Mammal Assessment Vessel Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets are a compilation of large vessel surveys for marine mammal stock assessments in the Gulf of Mexico from 1991 to the present. These are designed as...

  1. 75 FR 38878 - Transportation for Individuals With Disabilities: Passenger Vessels

    Science.gov (United States)

    2010-07-06

    ... the vessel. A terminal, in this sense, can be a large complex, a building, or a very simple facility... mobility impairments as opposed to persons with other disabilities such as hearing or vision...

  2. Gulf of Mexico Marine Mammal Vessel Surveys - NRDA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large vessel surveys were conducted during June-August and Oct-Nov, 2010 in the north central Gulf of Mexico to collect data on marine mammal spatial distribution...

  3. 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

  4. Flow patterns on spectral-domain optical coherence tomography reveal flow directions at retinal vessel bifurcations

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Q; Munch, Inger C

    2014-01-01

    PURPOSE: To study intravascular characteristics of flowing blood in retinal vessels using spectral-domain optical coherence tomography (SD-OCT). METHODS: Examination of selected arterial bifurcations and venous sites of confluence in 25 healthy 11-year-old children recruited as an ad hoc subsample...... be determined using SD-OCT. This feature may assist the identification of flow reversal near sites of vascular occlusion, the analysis of blood flow near vascular malformations and the segmentation of retinal SD-OCT images....

  5. Vessel enhancing diffusion: a scale space representation of vessel structures.

    Science.gov (United States)

    Manniesing, Rashindra; Viergever, Max A; Niessen, Wiro J

    2006-12-01

    A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature.

  6. Assessment of the attenuation of an intra-abdominal vein by use of a silicone-polyacrylic acid gradual venous occlusion device in dogs and cats.

    Science.gov (United States)

    Wallace, Mandy L; Ellison, Gary W; Giglio, Robson F; Batich, Christopher D; Berry, Clifford R; Case, J Brad; Kim, Stanley E

    2016-06-01

    OBJECTIVE To evaluate the closure rate and completeness of closure for a silicone-polyacrylic acid gradual venous occlusion device placed around an intra-abdominal vein to simulate gradual occlusion of an extrahepatic portosystemic shunt. ANIMALS 3 purpose-bred cats and 2 purpose-bred dogs. PROCEDURES The device was surgically placed around an external (cats) or internal (dogs) iliac vein. Computed tomographic angiography was performed at the time of surgery and 2, 4, and 6 weeks after surgery. Ultrasonographic examinations of blood flow through the vein within the device were performed at the time of surgery and at weekly intervals thereafter. Dogs were euthanized 6 weeks after surgery, and the external iliac veins were harvested for histologic examination. RESULTS The prototype gradual venous occlusion device was successfully placed in all animals, and all animals recovered without complications following the placement procedure. The vessel was completely occluded in 2 cats by 6 weeks after surgery, as determined on the basis of results of CT and ultrasonography; there was incomplete occlusion with a luminal diameter of 1.5 mm in the other cat by 6 weeks after surgery. The vessel was completely occluded in both dogs by 6 weeks after surgery. Histologic examination of the external iliac veins obtained from the dogs revealed minimal inflammation of the vessel wall and no thrombus formation. CONCLUSIONS AND CLINICAL RELEVANCE The prototype device induced gradual attenuation of an intra-abdominal vessel over a 6-week period. This device may provide another option for gradual occlusion of extrahepatic portosystemic shunts.

  7. Clinical results with the Resolute zotarolimus-eluting stent in total coronary occlusions

    DEFF Research Database (Denmark)

    Kelbæk, Henning; Holmvang, Lene; Richardt, Gert

    2015-01-01

    and results: Patients were divided into three groups: chronic TO (CTO; n=256), non-chronic TO (n=292), and no occlusion (n=2,941). Clinical and safety outcomes assessed through two years included target lesion failure (TLF: cardiac death, target vessel myocardial infarction, and clinically driven target...... lesion revascularisation) and Academic Research Consortium definite or probable stent thrombosis. The rate of TLF at two years was not significantly different among patients in the CTO (9.1%), TO (9.8%), and no occlusion (10.4%) groups (log-rank p=0.800); neither were the components of TLF. Definite...... or probable stent thrombosis occurred more frequently in the TO group (2.8% vs. 1.2% in the CTO and 1.1% in the group with no occlusion, p=0.027). There were 10 late and six very late stent thrombosis events. Conclusions: Apart from a higher rate of stent thrombosis in patients with TO, patients with totally...

  8. Vessel enhancing diffusion: a scale space representation of vessel

    OpenAIRE

    Manniesing, Rashindra; Viergever, M.A.; Niessen, Wiro

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffus...

  9. Management of life-threatening celiac-hepatic arterial hemorrhage after pancreaticoduodenectomy: usefulness of temporary balloon occlusion

    Institute of Scientific and Technical Information of China (English)

    WANG Mao-qiang; GUO Li-ping; LIN Han-ying; DUAN Feng; LIU Feng-yong; WANG Zhi-jun

    2011-01-01

    When a large visceral artery is ruptured,uncontrolled bleeding may lead to hemodynamic collapse.Use of endovascular occlusion balloon catheter may provide rapid control of hemorrhage and facilitate definitive therapy.We reported two patients with massive hemorrhage from ruptured celiac-hepatic artery after pancreaticoduodenectomy,who were initially treated percutaneously by temporary selective balloon occlusion.They became critically hemodynamic unstable during the angiographic procedure.Through an 8Fr sheath,a 6Fr compliant latex occlusion balloon was placed proximal to the celiac trunk and inflated,and upon patient stabilization surgical revision and stent-graft placement were successfully performed in the two patients,respectively.Temporary selective balloon occlusion provides fast and effective bleeding control for patient with critically uncontrollable visceral arterial hemorrhage,permitting subsequent use of conventional techniques for management of the arterial bleeding source.

  10. Intravascular Ultrasound in Percutaneous Coronary Intervention for Chronic Total Occlusion

    Directory of Open Access Journals (Sweden)

    M Mohandes

    2010-09-01

    Full Text Available Background: Percutaneous coronary intervention (PCI of chronic total occlusion (CTO is one of the most challenging procedures in interventional cardiology. New techniques and devices have made possible to face these complex procedures. Intravascular ultrasound (IVUS reveals special features and contributes greatly to procedural success.Method: We analysed retrospectively IVUS contribution and findings in 23 cases of a total 46 CTOs PCI from February 2009 to August 2010 in our cath lab. Both true and functional CTO were included in this study. The procedure was considered successful when a TIMI III flow was reached in the occluded vessel after stent implantation with a residual stenosis less than 30%. IVUS features and contribution in CTO-PCI were analysed. All data were introduced in SPSS version 15 (SPSS Inc. Chicago, Illinois, USA. Continuous variables were described by mean ± SD and categorical variables were expressed as percentage. A P<0.05 was considered statistically significant.Results: 46 PCIs in 34 patients were performed during 19 months in our centre. The procedure was successful in 28 cases (60.9%.. IVUS was performed in 23 (82.1% of successful procedures. IVUS revealed calcium somewhere in 17 (73.9%. Despite wire angiographic verification in true lumen distally IVUS showed subintimal wire position in part of CTO segment in 6(26.1%. In 22(95.7% of cases IVUS allowed both the wire position verification in true lumen and the vessel measurement before stent implantation. In 1(4.3% case a second wire was introduced into true lumen guided by IVUS after realising that the first wire was in false lumen. We could not find significant relation between calcium presence and subintimal wire penetration in CTO segment (p: 0.14 Conclusions: IVUS showed calcium in CTO segment in a high percentage of cases. It is not unusual to find wire penetration in subintimal space in part of CTO segment. IVUS has a key contribution in the step by step

  11. Vessel generator noise as a settlement cue for marine biofouling species.

    Science.gov (United States)

    McDonald, J I; Wilkens, S L; Stanley, J A; Jeffs, A G

    2014-01-01

    Underwater noise is increasing globally, largely due to increased vessel numbers and international ocean trade. Vessels are also a major vector for translocation of non-indigenous marine species which can have serious implications for biosecurity. The possibility that underwater noise from fishing vessels may promote settlement of biofouling on hulls was investigated for the ascidian Ciona intestinalis. Spatial differences in biofouling appear to be correlated with spatial differences in the intensity and frequency of the noise emitted by the vessel's generator. This correlation was confirmed in laboratory experiments where C. intestinalis larvae showed significantly faster settlement and metamorphosis when exposed to the underwater noise produced by the vessel generator. Larval survival rates were also significantly higher in treatments exposed to vessel generator noise. Enhanced settlement attributable to vessel generator noise may indicate that vessels not only provide a suitable fouling substratum, but vessels running generators may be attracting larvae and enhancing their survival and growth.

  12. Complex neurological symptoms in bilateral thalamic stroke due to Percheron artery occlusion

    Science.gov (United States)

    Caruso, Paola; Manganotti, Paolo; Moretti, Rita

    2017-01-01

    The artery of Percheron is a rare anatomical variant where a single thalamic perforating artery arises from the proximal posterior cerebral artery (P1 segment) between the basilar artery and the posterior communicating artery and supplies the rostral mesencephalon and both paramedian territories of the thalami. Almost one-third of human brains present this variant. Occlusion of the artery of Percheron mostly results in a bilateral medial thalamic infarction, which usually manifests with altered consciousness (including coma), vertical gaze paresis, and cognitive disturbance. The presentation is similar to the “top of the basilar syndrome”, and early recognition should be prompted. We describe the case of a young female with this vessel variant who experienced a bilateral thalamic stroke. Magnetic resonance angiography demonstrated bilateral thalamic infarcts and a truncated artery of Percheron. Occlusion of the vessel was presumably due to embolism from a patent foramen ovale. Thrombolysis was performed, with incomplete symptom remission, cognitive impairment, and persistence of speech disorders. Early recognition and treatment of posterior circulation strokes is mandatory, and further investigation for underlying stroke etiologies is needed. PMID:28053539

  13. Interaction of xylem and phloem during exudation and wound occlusion in Cucurbita maxima.

    Science.gov (United States)

    Zimmermann, Matthias R; Hafke, Jens B; van Bel, Aart J E; Furch, Alexandra C U

    2013-01-01

    Collection of cucurbit exudates from cut petioles has been a powerful tool for gaining knowledge on phloem sap composition without full notion of the complex exudation mechanism. Only few publications explicitly mentioned that exudates were collected from the basal side of the cut, which exudes more copiously than the apical side. This is surprising since only exudation from the apical side is supposedly driven by phloem pressure gradients. Composition of carbohydrates and pH values at both wounding sides are equal, whereas protein concentration is higher at the basal side. Apparently, exudation is far more complex than just the delivery of phloem sap. Xylem involvement is indicated by lower protein concentrations after elimination of root pressure. Moreover, dye was sucked into xylem vessels owing to relaxation of negative pressure after cutting. The lateral water efflux from the vessels increases turgor of surrounding cells including sieve elements. Simultaneously, detached parietal proteins (PP1/PP2) induce occlusion of sieve plates and cover wound surface. If root pressure is strong enough, pure xylem sap can be collected after removal of the occlusion plug at the wound surface. The present findings provide a mechanism of sap exudation in Cucurbita maxima, in which the contribution of xylem water is integrated. © 2012 Blackwell Publishing Ltd.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Restoration of posterior teeth using occlusal matrix technique

    Directory of Open Access Journals (Sweden)

    Martos Josue

    2010-01-01

    Full Text Available This article describes a technique for duplicating occlusal surface anatomy using the Biteperf device. Duplication requires an intact occlusal enamel surface and is only indicated when caries lesions are hidden. The occlusal matrix technique allows for preservation of all anatomic details. When the last layer of composite has been placed, the occlusal matrix is forced into the uncured composite to replicate the original occlusal surface, instead of performing manual curing and shaping as in the standard approach. It is technically possible to achieve this effect with any material that is able to copy anatomic details. The main benefits of the occlusal matrix technique, more precisely the Biteperf, are the technical ease of use due to its simplicity and its high accuracy in reconstructing occlusal morphology.

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

    Science.gov (United States)

    Rangarajan, V.; Gajapathi, B.; Yogesh, P. B.; Ibrahim, M. Mohamed; Kumar, R. Ganesh; Karthik, Prasanna

    2015-01-01

    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. PMID:26929513

  17. RTSAH Traversal Order for Occlusion Rays

    KAUST Repository

    Ize, Thiago

    2011-04-01

    We accelerate the finding of occluders in tree based acceleration structures, such as a packetized BVH and a single ray kd-tree, by deriving the ray termination surface area heuristic (RTSAH) cost model for traversing an occlusion ray through a tree and then using the RTSAH to determine which child node a ray should traverse first instead of the traditional choice of traversing the near node before the far node. We further extend RTSAH to handle materials that attenuate light instead of fully occluding it, so that we can avoid superfluous intersections with partially transparent objects. For scenes with high occlusion, we substantially lower the number of traversal steps and intersection tests and achieve up to 2× speedups. © 2010 The Author(s).

  18. Handling Occlusions for Robust Augmented Reality Systems

    Directory of Open Access Journals (Sweden)

    Madjid Maidi

    2010-01-01

    Full Text Available 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.

  19. Handling Occlusions for Robust Augmented Reality Systems

    Directory of Open Access Journals (Sweden)

    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.

  20. Nontraumatic vascular emergencies: imaging and intervention in acute venous occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Haage, Patrick; Schmitz-Rode, Thomas [Department of Diagnostic Radiology, University of Technology Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Krings, Timo [Department of Neuroradiology, University of Technology Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany)

    2002-11-01

    Risk factors for acute venous occlusion range from prolonged immobilization to hypercoagulability syndromes, trauma, and malignancy. The aim of this review article is to illustrate the different imaging options for the diagnosis of acute venous occlusion and to assess the value of interventional strategies for venous thrombosis treatment in an emergency setting. First, diagnosis and treatment of the most common form of venous occlusion, at the level of the lower extremities, is presented, followed by pelvic vein and inferior vena cava occlusion, mesenteric venous thrombosis, upper extremity occlusion, acute cerebral vein thrombosis, and finally acute venous occlusion of hemodialysis access. In acute venous occlusion of the lower extremity phlebography is still the reference gold standard. Presently, duplex ultrasound with manual compression is the most sensitive and specific noninvasive test. Limitations of ultrasonography include isolated distal calf vein occlusion, obesity, and patients with lower extremity edema. If sonography is nondiagnostic, venography should be considered. Magnetic resonance venography can differentiate an acute occlusion from chronic thrombus, but because of its high cost and limited availability, it is not yet used for the routine diagnosis of lower extremity venous occlusion only. Regarding interventional treatment, catheter-directed thrombolysis can be applied to dissolve thrombus in charily selected patients with symptomatic occlusion and no contraindications to therapy. Acute occlusion of the pelvic veins and the inferior vena cava, often due to extension from the femoropopliteal system, represents a major risk for pulmonary embolism. Color flow Doppler imaging is often limited owing to obesity and bowel gas. Venography has long been considered the gold standard for identifying proximal venous occlusion. Both CT scanning and MR imaging, however, can even more accurately diagnose acute pelvis vein or inferior vena cava occlusion. MRI is

  1. The vessel fluence; Fluence cuve

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This book presents the proceedings of the technical meeting on the reactors vessels fluence. They are grouped in eight sessions: the industrial context and the stakes of the vessels control; the organization and the methodology for the fluence computation; the concerned physical properties; the reference computation methods; the fluence monitoring in an industrial context; vessels monitoring under irradiation; others methods in the world; the research and development programs. (A.L.B.)

  2. NANOROBOTS CONTROL ACTIVATION FOR STENOSED CORONARY OCCLUSION

    OpenAIRE

    Christo Ananth; R.K. Shunmuga Priya; T.Rashmi Anns; S.Kadhirunnisa

    2017-01-01

    This paper presents the study of nanorobots control activation for stenosed coronary occlusion, with the practical use of chemical and thermal gradients for biomedical problems. The recent developments on nanotechnology new materials allied with electronics device miniaturization may enable nanorobots for the next few years. New possibilities for medicine are expected with the development of nanorobots. It may help to advance the treatment of a wide number ...

  3. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  4. Coal gasification vessel

    Science.gov (United States)

    Loo, Billy W.

    1982-01-01

    A vessel system (10) comprises an outer shell (14) of carbon fibers held in a binder, a coolant circulation mechanism (16) and control mechanism (42) and an inner shell (46) comprised of a refractory material and is of light weight and capable of withstanding the extreme temperature and pressure environment of, for example, a coal gasification process. The control mechanism (42) can be computer controlled and can be used to monitor and modulate the coolant which is provided through the circulation mechanism (16) for cooling and protecting the carbon fiber and outer shell (14). The control mechanism (42) is also used to locate any isolated hot spots which may occur through the local disintegration of the inner refractory shell (46).

  5. Dental Occlusion and Ophthalmology: A Literature Review

    Science.gov (United States)

    Marchili, Nicola; Ortu, Eleonora; Pietropaoli, Davide; Cattaneo, Ruggero; Monaco, Annalisa

    2016-01-01

    Stomatognathic system is strictly correlated to other anatomical regions; many studies investigated relationship between temporomandibular joint and posture, several articles describe cranio-facial pain from dental causes, such as trigger points. Until now less interest has been given to connections between dental occlusion and ophthalmology, even if they are important and involving. Clinical experience in dental practice claims that mandibular latero-deviation is connected both to eye dominance and to defects of ocular convergence. The trigeminal nerve is the largest and most complex of the twelve cranial nerves. The trigeminal system represents the connection between somitic structures and those derived from the branchial arches, collecting the proprioception from both somitic structures and oculomotor muscles. The intermedius nucleus of the medulla is a small perihypoglossal brainstem nucleus, which acts to integrate information from the head and neck and relays it on to the nucleus of the solitary tract where autonomic responses are generated. This intriguing neurophysiological web led our research group to investigate anatomical and functional associations between dental occlusion and vision. In conclusion, nervous system and functional pathways strictly connect vision and dental occlusion, and in the future both dentists and oculists should be more and more aware of this correlation for a better diagnosis and therapy. PMID:27733873

  6. Laser photocoagulation for retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    K. A. Mirzabekova

    2015-03-01

    Full Text Available Retinal vein occlusion (RVO is one of the leading causes of permanent vision loss. In adults, central retinal vein occlusion (CRVO occurs in 1.8% while branch retinal vein occlusion (BRVO occurs in 0.2%. Treatment strategy and disease prognosis are determined by RVO type (ischemic/non-ischemic. Despite numerous studies and many current CRVO and BRVO treatment approaches, the management of these patients is still being debated. Intravitreal injections of steroids (triamcinolone acetate, dexamethasone and vascular endothelial growth factor (VEGF inhibitors (bevacizumab, ranibizumab were shown to be fairly effective. However, it is unclear whether anti-VEGF agents are reasonable in ischemic RVOs. Laser photocoagulation remains the only effective treatment of optic nerve head and/or retinal neovascularization. Laser photocoagulation is also indicated for the treatment of macular edema. Both threshold and sub-threshold photocoagulation may be performed. Photocoagulation performed with argon (514 nm, krypton (647 nm, or diode (810 nm laser for macular edema provides similar results (no significant differences. The treatment may be complex and include medication therapy and/or surgery. Medication therapy includes anti-aggregant agents and antioxidants, i.e., emoxypine which may be used in acute RVO as well as in post-thrombotic retinopathy. 

  7. Fouling in your own nest: vessel noise increases biofouling.

    Science.gov (United States)

    Stanley, Jenni A; Wilkens, Serena L; Jeffs, Andrew G

    2014-01-01

    Globally billions of dollars are spent each year on attempting to reduce marine biofouling on commercial vessels, largely because it results in higher fuel costs due to increased hydrodynamic drag. Biofouling has been long assumed to be primarily due to the availability of vacant space on the surface of the hull. Here, it is shown that the addition of the noise emitted through a vessel's hull in port increases the settlement and growth of biofouling organisms within four weeks of clean surfaces being placed in the sea. More than twice as many bryozoans, oysters, calcareous tube worms and barnacles settled and established on surfaces with vessel noise compared to those without. Likewise, individuals from three species grew significantly larger in size in the presence of vessel noise. The results demonstrate that vessel noise in port is promoting biofouling on hulls and that underwater sound plays a much wider ecological role in the marine environment than was previously considered possible.

  8. Emergent stent-assisted angioplasty of extracranial internal carotid artery and intracranial stent-based thrombectomy in acute tandem occlusive disease: technical considerations.

    Science.gov (United States)

    Cohen, José E; Gomori, Moshe; Rajz, Gustavo; Moscovici, Samuel; Leker, Ronen R; Rosenberg, Shai; Itshayek, Eyal

    2013-09-01

    Tandem occlusions of the internal carotid artery (ICA) and a major intracranial artery respond poorly to intravenous thrombolytic therapy, and are usually managed by endovascular means. This study describes experience with stent-assisted endovascular ICA revascularization and stent-based thrombectomy. In patients with tandem ICA-middle cerebral artery (MCA)/distal ICA occlusion, the carotid occlusion was recanalized by primary angioplasty and stent implantation, and the distal occlusion by stent-based thrombectomy. Two variant techniques are described. Seven consecutive patients, mean age 64.1 years (range 49-75) and mean admission National Institutes of Health Stroke Scale score of 23, were included. Occlusion sites were tandem proximal ICA and MCA trunk (six patients) and tandem proximal left ICA and ICA terminus (one patient). Complete recanalization with complete perfusion (Thrombolysis in Myocardial Infarction [TIMI] 3, Thrombolysis in Cerebral Infarction [TICI] 3) was achieved in six patients and partial recanalization with partial perfusion (TIMI 2, TICI 2A) in one. Mean time to therapy was 4.9 h (range 3-6.5); mean time to recanalization was 55 min (range 38-65 min). CT performed 1 day after recanalization showed cortical sparing (>90% of the cortex at risk) in seven patients. Five patients (72%) presented with good clinical outcome (modified Rankin Scale (mRS) score 0-2) at 1 month; one patient (patient No 7) reached an mRS score of 3 and one patient died. In selected cases of acute ICA occlusion and concomitant major vessel embolic stroke, angioplasty and stenting of the proximal occlusion and stent-based thrombectomy of the intracranial occlusion may be feasible, effective and safe, and provide early neurological improvement. Further experience and prospective studies are warranted.

  9. Relationship of Occlusal Schemes with the Occurrence of Temporomandibular Disorders

    Directory of Open Access Journals (Sweden)

    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.

  10. 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.

  11. Multi-scale Visualization of Molecular Architecture Using Real-Time Ambient Occlusion in Sculptor.

    Science.gov (United States)

    Wahle, Manuel; Wriggers, Willy

    2015-10-01

    The modeling of large biomolecular assemblies relies on an efficient rendering of their hierarchical architecture across a wide range of spatial level of detail. We describe a paradigm shift currently under way in computer graphics towards the use of more realistic global illumination models, and we apply the so-called ambient occlusion approach to our open-source multi-scale modeling program, Sculptor. While there are many other higher quality global illumination approaches going all the way up to full GPU-accelerated ray tracing, they do not provide size-specificity of the features they shade. Ambient occlusion is an aspect of global lighting that offers great visual benefits and powerful user customization. By estimating how other molecular shape features affect the reception of light at some surface point, it effectively simulates indirect shadowing. This effect occurs between molecular surfaces that are close to each other, or in pockets such as protein or ligand binding sites. By adding ambient occlusion, large macromolecular systems look much more natural, and the perception of characteristic surface features is strongly enhanced. In this work, we present a real-time implementation of screen space ambient occlusion that delivers realistic cues about tunable spatial scale characteristics of macromolecular architecture. Heretofore, the visualization of large biomolecular systems, comprising e.g. hundreds of thousands of atoms or Mega-Dalton size electron microscopy maps, did not take into account the length scales of interest or the spatial resolution of the data. Our approach has been uniquely customized with shading that is tuned for pockets and cavities of a user-defined size, making it useful for visualizing molecular features at multiple scales of interest. This is a feature that none of the conventional ambient occlusion approaches provide. Actual Sculptor screen shots illustrate how our implementation supports the size-dependent rendering of molecular

  12. Multi-scale Visualization of Molecular Architecture Using Real-Time Ambient Occlusion in Sculptor.

    Directory of Open Access Journals (Sweden)

    Manuel Wahle

    2015-10-01

    Full Text Available The modeling of large biomolecular assemblies relies on an efficient rendering of their hierarchical architecture across a wide range of spatial level of detail. We describe a paradigm shift currently under way in computer graphics towards the use of more realistic global illumination models, and we apply the so-called ambient occlusion approach to our open-source multi-scale modeling program, Sculptor. While there are many other higher quality global illumination approaches going all the way up to full GPU-accelerated ray tracing, they do not provide size-specificity of the features they shade. Ambient occlusion is an aspect of global lighting that offers great visual benefits and powerful user customization. By estimating how other molecular shape features affect the reception of light at some surface point, it effectively simulates indirect shadowing. This effect occurs between molecular surfaces that are close to each other, or in pockets such as protein or ligand binding sites. By adding ambient occlusion, large macromolecular systems look much more natural, and the perception of characteristic surface features is strongly enhanced. In this work, we present a real-time implementation of screen space ambient occlusion that delivers realistic cues about tunable spatial scale characteristics of macromolecular architecture. Heretofore, the visualization of large biomolecular systems, comprising e.g. hundreds of thousands of atoms or Mega-Dalton size electron microscopy maps, did not take into account the length scales of interest or the spatial resolution of the data. Our approach has been uniquely customized with shading that is tuned for pockets and cavities of a user-defined size, making it useful for visualizing molecular features at multiple scales of interest. This is a feature that none of the conventional ambient occlusion approaches provide. Actual Sculptor screen shots illustrate how our implementation supports the size

  13. Identifying All True Vessels from Segmented Retinal Images

    Directory of Open Access Journals (Sweden)

    G. Delucta Mary

    2014-02-01

    Full Text Available Measurements of retinal blood vessel morphology have been shown to be related to the risk of cardiovascular diseases. The wrong identification of vessels may result in a large variation of these measurements, leading to a wrong clinical diagnosis Both the arteries and veins of the retina are generally binary trees, whose properties can be considered either locally or globally. Measurable geometrical changes in diameter, branching angle, length, or tortuosity, as a result of disease, have been described in retinal blood vessels. The detection and measurement of retinal blood vessels can be used to quantify the severity of disease such as hypertension, stroke and arteriosclerosis, as part of the process of automated diagnosis of disease or in the assessment of the progression of therapy. Thus, a reliable method of vessel detection and quantification would be valuable. In this paper, we address the problem of identifying true vessels as a postprocessing step to vascular structure segmentation. We model the segmented vascular structure as a vessel segment graph and formulate the problem of identifying vessels as one of finding the optimal forest in the graph given a set of constraints.

  14. Summary of Reported Whale-Vessel Collisions in Alaskan Waters

    Directory of Open Access Journals (Sweden)

    Janet L. Neilson

    2012-01-01

    Full Text Available Here we summarize 108 reported whale-vessel collisions in Alaska from 1978–2011, of which 25 are known to have resulted in the whale's death. We found 89 definite and 19 possible/probable strikes based on standard criteria we created for this study. Most strikes involved humpback whales (86% with six other species documented. Small vessel strikes were most common (<15 m, 60%, but medium (15–79 m, 27% and large (≥80 m, 13% vessels also struck whales. Among the 25 mortalities, vessel length was known in seven cases (190–294 m and vessel speed was known in three cases (12–19 kn. In 36 cases, human injury or property damage resulted from the collision, and at least 15 people were thrown into the water. In 15 cases humpback whales struck anchored or drifting vessels, suggesting the whales did not detect the vessels. Documenting collisions in Alaska will remain challenging due to remoteness and resource limitations. For a better understanding of the factors contributing to lethal collisions, we recommend (1 systematic documentation of collisions, including vessel size and speed; (2 greater efforts to necropsy stranded whales; (3 using experienced teams focused on determining cause of death; (4 using standard criteria for validating collision reports, such as those presented in this paper.

  15. Evaluation of the effect of two different occlusal splints on maximum occlusal force in patients with sleep bruxism: a pilot study

    OpenAIRE

    2014-01-01

    PURPOSE The occlusal splint has been used for many years as an effective treatment of sleep bruxism. Several methods have been used to evaluate efficiency of the occlusal splints. However, the effect of the occlusal splints on occlusal force has not been clarified sufficiently. The purpose of this study was to evaluate the effect of occlusal splints on maximum occlusal force in patients with sleep bruxism and compare two type of splints that are Bruxogard-soft splint and canine protected hard...

  16. Bronze Vessel with Silkworm Motif

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    This artifact was a kind of sacrificial vessel used during the Shang and Zhou dynasties. Most patterns found on these pieces are the fierce and formidable faces of beasts or mysterious dragons, tigers and phoenixes. Rut the pattern on this vessel illustrates the life of a mulberry field.

  17. Meta-analysis of the effect of percutaneous coronary intervention on chronic total coronary occlusions

    Science.gov (United States)

    2014-01-01

    Background and purpose Coronary chronic total occlusion (CTO) is the last stage of coronary artery atherosclerosis. Percutaneous coronary intervention (PCI) is a therapeutic procedure used to recanalize vessels with total occlusion. However, successful recanalization of CTO is still not optimal, and the key influence factors are still uncertainty. Therefore, a scientific evaluation on the effective of PCI for CTO treatment is necessary. Methods Relevant studies of PCI treatment for CTO were examined. Data were extracted and assessed by two independent clinical experts. Embase, PubMed and Medline et al. were used as database. The main research key words include “CTO”, “PCI”, “Stent”, “Reopen”, “long-term”, “follow-up” and “outcome”. Quality assessment was carried out according to the Cochrane Handbook. The selected data were pooled and analyzed using fixed-effect model and random-effect model. Heterogeneity was assessed using the I2 test, Q test, L’abbe and Galbraith. Comprehensive Meta -Analysis 2.0 and Metanalysis 1.0 were used for statistics analysis in this research. Results A total of 16 articles involving 6695 cases in successful CTO recanalization (CTO success group) and 2370 cases in failed CTO recanalization(CTO failure group) were included in this research. Low CTO success was associated with elder age, previous coronary artery bypass graft surgery (CABG) history, multi-vessel diseases and right coronary artery disease lesion. Six follow-up variables including major adverse cardiac events (MACE), recurrent myocardial infarction (MI), all-cause death, incidence of angina, subsequent CABG and cumulative survival rate were found significantly reduced associated with CTO success. Conclusions Clinical baseline characteristics such as age, previous CABG history and lesion baseline characteristics such as lesion length, multi-vessel diseases might be important factors influencing the successful rate of CTO recanalization. Compared to

  18. AUTOMATIC RETINAL VESSEL TORTUOSITY MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Nidhal Khdhair El Abbadi

    2013-01-01

    Full Text Available Retinal vascular vessels have the role to indicate the retinal diseases and for systematic diseases when there are any abnormalities in retinal vascular pattern. A characteristic of the vascular pattern that is appreciated by clinicians is vascular tortuosity, i.e., how curved or kinked a blood vessel, either vein or artery, appears along its course. In this study we suggest a novel mask filter to track the blood vessel along its course and measuring the blood vessels tortuosity over the entire human retinal vessel network in fundus eye image, by using the arc to chord ratio. The suggested algorithm tested with straight and curve hand drawing lines and gives high accurate results.

  19. Strain Growth in Containment Vessels

    Institute of Scientific and Technical Information of China (English)

    DONG Q; LI Q M; ZHENG J Y

    2006-01-01

    Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading.The elastic response of the vessel may become larger in a later stage compared to its response during the initial stage.The dynamic responses of infinitely long cylindrical containment vessels subjected to uniformly-distributed internal blast loading are studied using LS-DYNA.The development of bending modes and the interaction between the breathing mode and bending modes are observed.The methodology developed for dynamic elastic buckling analysis is employed to study the strain growth phenomenon in explosion containment vessels.It is shown that the dynamic instable vibration of a containment vessel is the basic mechanism of strain growth.

  20. Vascular patterning: coordinated signals keep blood vessels on track.

    Science.gov (United States)

    Meadows, Stryder M; Cleaver, Ondine

    2015-06-01

    The vascular system is a complex, largely stereotyped network of interconnecting and branching vessels. How thousands of vessels form at precise locations is a key question regarding vascular morphogenesis. In order to achieve this defined architecture, the embryo integrates a multitude of attractive and repulsive cues to guide and shape the developing vasculature. This review summarizes recent studies investigating the interactions between endothelial cells and signals from surrounding tissues that pattern the initial blood vessel network. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Passive Acoustic Vessel Localization

    Science.gov (United States)

    Suwal, Pasang Sherpa

    This thesis investigates the development of a low-cost passive acoustic system for localizing moving vessels to monitor areas where human activities such as fishing, snorkeling and poaching are restricted. The system uses several off-the-shelf sensors with unsynchronized clocks where the Time Difference of Arrival (TDOA) or time delay is extracted by cross-correlation of the signal between paired sensors. The cross-correlation function uses phase correlation or Phase Transform (PHAT) which whitens the cross-spectrum in order to de-emphasize dominant frequency components. Using the locations of pairs of sensors as foci, hyperbolic equations can be defined using the time delay between them. With three or more sensors, multiple hyperbolic functions can be calculated which intersect at a unique point: the boat's location. It is also found that increasing separation distances between sensors decreased the correlation between the signals. However larger separation distances have better localization capability than with small distances. Experimental results from the Columbia and Willamette Rivers are presented to demonstrate performance.

  2. Cephalometric Indicators of the Vertical Dimension of Occlusion

    OpenAIRE

    Strajnić, Ljiljana; Stanišić-Sinobad, Darinka; Marković, Dubravka; Stojanović, Ljiljana

    2008-01-01

    The aim of this investigation was to establish precise indicators of the vertical dimension of occlusion (VDO) which could be used as objective parameters in prosthodontic treatment providing exact control of the reconstructed vertical dimension of occlusion, early detection of errors and correction of the vertical dimension of occlusion during complete denture manufacturing. A total of 60 lateral cephalometric radiographs of subjects with natural dentition and class I skeletal ja...

  3. Importance of occlusion aspects in the completion of orthodontic treatment

    OpenAIRE

    2007-01-01

    The purpose of this study was to address the therapeutic goals regarding the static and functional occlusion in the completion of orthodontic treatment. For such purpose, a study population comprising 20 female treated Class II malocclusion subjects with an initial mean age of 11 years underwent a two-phase treatment (orthopedics and orthodontics). The patients were diagnosed in centric relation and were treated according to the six keys for normal occlusion and functional occlusal parameters...

  4. 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.

  5. Occlusal adjustment in the treatment of secondary traumatic injury

    Directory of Open Access Journals (Sweden)

    Raulino Naves Borges

    2011-01-01

    Full Text Available The success of the rehabilitation treatment is associated with the relationship between occlusion and periodontal status. When occlusal loads exceed the ability of the periodontium to resist and distribute the resulting forces, injuries may develop, leading to failures in dental practice. A 35-year-old female patient presented at the Occlusion and Orofacial Pain Research Center at the School of Dentistry, Universidade Federal de Goiás, Brazil, complaining of pain and mobility in the maxillary central incisors and sensitivity in the mandibular left incisors and canine. Symptoms began after cast metal restoration was performed in tooth #27. Clinical examination revealed a signifi cant difference of 1 mm between centric relation and habitual occlusion, presence of a periodontal pocket 5 mm deep in the mesial aspect of tooth #11, and an increased vertical dimension of occlusion caused by occlusal interference between teeth #27 and #37. Radiographic examination detected vertical bone loss between teeth #21 and #11, on the mesial aspect of tooth #33 and between the lower incisors. The lower teeth also showed radiographic evidence of periapical lesions. Occlusal interference caused anterior projection of the mandible to the right, overloading the incisors. Treatment by occlusal adjustment was performed to promote an equal incidence of forces on all aspects of the teeth. Twelve sessions were required to achieve a balanced occlusion and restore the physiological vertical dimension of occlusion. Six months after treatment, there was radiographic evidence of newly formed bone tissue between teeth #11 and #21, regression of apical periodontitis in the lower teeth, and a decrease in mobility and all associated symptoms. Secondary traumatic injury may be responsible for changes in apical tooth structures. Occlusal adjustment may favor the direction of occlusal forces to the long axis of the teeth.

  6. On the maximum sufficient range of interstellar vessels

    CERN Document Server

    Cartin, Daniel

    2011-01-01

    This paper considers the likely maximum range of space vessels providing the basis of a mature interstellar transportation network. Using the principle of sufficiency, it is argued that this range will be less than three parsecs for the average interstellar vessel. This maximum range provides access from the Solar System to a large majority of nearby stellar systems, with total travel distances within the network not excessively greater than actual physical distance.

  7. 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.

  8. Electro-oculogram of Retinal Vein Occlusion

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs ...

  9. Central Retinal Vein Occlusion Revealing Coelic Disease

    Directory of Open Access Journals (Sweden)

    Hana ZOUBEIDI

    2016-11-01

    Full Text Available Introduction: Thrombosis has been widely reported in coeliac disease (CD but central retinal vein occlusion (CRVO is rarely described. Case presentation: A 27-year-old woman presented with acute visual loss and was diagnosed with CRVO. Her protein S and protein C levels were low and CD was diagnosed on the basis of endoscopic, immunological and histological results. A gluten-free diet resulted in favourable evolution. Conclusion: CD should be considered in young patients with thrombosis, especially if in an unusual location. Treatment is based on a gluten-free diet.

  10. Arterial gas occlusions in operating heat pipes

    Science.gov (United States)

    Saaski, E. W.

    1975-01-01

    The effect of noncondensable gases on high performance arterial heat pipes has been investigated both analytically and experimentally. Models have been generated which characterize the dissolution of gases in condensate and the diffusional loss of dissolved gases from condensate in arterial flow. These processes, and others, have been used to postulate stability criteria for arterial heat pipes. Experimental observations of gas occlusions were made using a stainless steel heat pipe equipped with viewing ports, and the working fluids methanol and ammonia with the gas additives helium, argon, and xenon. Observations were related to gas transport models.

  11. Endothelium-dependent relaxation of blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Hynes, M.R.

    1987-01-01

    Dilation of blood vessels in response to a large number of agents has been shown to be dependent on an intact vascular endothelium. The present studies examine some aspects of endothelium-dependent vasodilation in blood vessels of the rabbit and rat. Using the rabbit ear artery and the subtype-selective muscarinic antagonist pirenzepine, muscarinic receptors of the endothelium and smooth muscle cells were shown to be of the low affinity M/sub 2/ subtype. Inhibition of (/sup 3/H)(-)quinuclidinyl benzilate was used to determine affinity for the smooth muscle receptors while antagonism of methacholine induced vasodilation yielded the endothelial cell receptor affinity. The effect of increasing age (1-27 months) on endothelium-dependent relaxation was studied in aortic rings, perfused tail artery and perfused mesenteric bed of the Fisher 344 rat. The influence of endothelium on contractile responses was examined using the perfused caudal artery.

  12. Multiscale Vessel-guided Airway Tree Segmentation

    DEFF Research Database (Denmark)

    2009-01-01

    This paper presents a method for airway tree segmentation that uses a combination of a trained airway appearance model, vessel and airway orientation information, and region growing. The method uses a voxel classification based appearance model, which involves the use of a classifier that is trai......This paper presents a method for airway tree segmentation that uses a combination of a trained airway appearance model, vessel and airway orientation information, and region growing. The method uses a voxel classification based appearance model, which involves the use of a classifier...... is evaluated within EXACT’09 on a diverse set of CT scans. Results show a favorable combination of a relatively large portion of the tree detected correctly with very few false positives....

  13. The occlusal guard: a simplified technique for fabrication and equilibration.

    Science.gov (United States)

    Antonelli, John; Hottel, Timothy L; Siegel, Sharon C; Brandt, Robert; Silva, Gladston

    2013-01-01

    Hard occlusal guards have been used effectively to treat myofacial pain originating from parafunctional activities. Also, they can protect the natural dentition when it opposes porcelain restorations, help to evaluate changes in occlusal vertical dimension during full mouth rehabilitation, minimize further tooth loss in patients with abfraction lesions, and redirect occlusal loads more favorably onto dental implant-supported prostheses. A simplified technique is described to fabricate a properly designed wax model of an occlusal guard that can be processed in acrylic in the same manner used to construct a complete denture.

  14. 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....

  15. 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.

  16. 2D Fast Vessel Visualization Using a Vessel Wall Mask Guiding Fine Vessel Detection

    Directory of Open Access Journals (Sweden)

    Sotirios Raptis

    2010-01-01

    and then try to approach the ridges and branches of the vasculature's using fine detection. Fine vessel screening looks into local structural inconsistencies in vessels properties, into noise, or into not expected intensity variations observed inside pre-known vessel-body areas. The vessels are first modelled sufficiently but not precisely by their walls with a tubular model-structure that is the result of an initial segmentation. This provides a chart of likely Vessel Wall Pixels (VWPs yielding a form of a likelihood vessel map mainly based on gradient filter's intensity and spatial arrangement parameters (e.g., linear consistency. Specific vessel parameters (centerline, width, location, fall-away rate, main orientation are post-computed by convolving the image with a set of pre-tuned spatial filters called Matched Filters (MFs. These are easily computed as Gaussian-like 2D forms that use a limited range sub-optimal parameters adjusted to the dominant vessel characteristics obtained by Spatial Grey Level Difference statistics limiting the range of search into vessel widths of 16, 32, and 64 pixels. Sparse pixels are effectively eliminated by applying a limited range Hough Transform (HT or region growing. Major benefits are limiting the range of parameters, reducing the search-space for post-convolution to only masked regions, representing almost 2% of the 2D volume, good speed versus accuracy/time trade-off. Results show the potentials of our approach in terms of time for detection ROC analysis and accuracy of vessel pixel (VP detection.

  17. Pattern of vascular remodeling of distal reference segment after recanalization of chronic total occlusion, long-term angiographic follow-up

    Directory of Open Access Journals (Sweden)

    Wassam El Din Hadad El Shafey

    2017-06-01

    Full Text Available Chronic total occlusion (CTO is probably caused by thrombus and lipid-rich cholesterol esters that are replaced over time by collagen and calcium deposition. Experimental models showed endothelial cell necrosis in response to vessel ligation, whereas more recent models suggest that the endothelium might retain viability guiding the subsequent development of CTO, including CTO neo-revascularization, which occurs within the lumen and in various layers of the vessel wall, by the release of paracrine substances. It is uncertain whether after CTO recanalization the recovery of anterograde reverses endothelial dysfunction, thus promoting vasodilation and positive remodeling.

  18. ECG-triggered non-contrast-enhanced MR angiography (TRANCE) versus digital subtraction angiography (DSA) in patients with peripheral arterial occlusive disease of the lower extremities

    Energy Technology Data Exchange (ETDEWEB)

    Gutzeit, Andreas [Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Sutter, Reto [Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); Froehlich, Johannes M.; Roos, Justus E.; Sautter, Thomas; Schoch, Erik; Giger, Barbara; Weymarn, Constantin von; Binkert, Christoph A. [Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Wyss, Michael [University and ETH Zurich, Institute for Biomedical Engineering, Zurich (Switzerland); Graf, Nicole [University Hospital of Zurich, Clinical Trials Center, Center for Clinical Research, Zurich (Switzerland); Jenelten, Regula [Cantonal Hospital Winterthur, Department of Angiology, Winterthur (Switzerland); Hergan, Klaus [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria)

    2011-09-15

    To prospectively determine the diagnostic value of electrocardiography-triggered non-contrast-enhanced magnetic resonance angiography (TRANCE) of the lower extremities including the feet versus DSA. All 43 patients with symptomatic peripheral arterial occlusive disease (PAOD) underwent TRANCE before DSA. Quality of MRA vessel depiction was rated by two independent radiologists on a 3-point scale. Arterial segments were graded for stenoses using a 4-point scale (grade 1: no stenosis; grade 2: moderate stenosis; grade 3: severe stenosis; grade 4: occlusion). Findings were compared with those of DSA. In the 731 vessel segments analysed, intra-arterial DSA revealed 283 stenoses: 33.6% moderate, 16.6% severe and 49.8% occlusions. TRANCE yielded a mean sensitivity, specificity, positive and negative predictive value and diagnostic accuracy to detect severe stenoses or occlusions of 95.6%, 97.4%, 87.2%, 99.2%, 97.1% for the thigh segments and 95.2%, 87.5%, 83.2%, 96.6%, 90.5% for the calf segments. Excellent overall image quality was observed for TRANCE in 91.4% versus 95.7% (DSA) for the thigh and in 60.7% versus 91.0% for the calves, while diagnostic quality of the pedal arteries was rated as insufficient. TRANCE achieves high diagnostic accuracy in the thigh and calf regions, whereas the pedal arteries showed limited quality. (orig.)

  19. Stent-assisted mechanical recanalization for symptomatic subacute or chronic middle cerebral artery occlusion

    Science.gov (United States)

    Guo, Dong; Ma, Ji; Li, Teng-Fei; Zhu, Ming; Han, Xin-Wei; Shui, Shao-Feng

    2015-01-01

    To assess the feasibility and short-term effects of treating patients with subacute or chronic middle cerebral artery (M1) occlusion by stent-assisted mechanical recanalization. Six patients with cerebral arteries occlusion underwent surgery. Six cerebral arteries occlusion in 5 patients were successfully recanalized. On postoperative day 1, four patients’ symptoms were relieved and two patients’ symptoms were exacerbated, of which one was significantly improved after 3 days, the other one’s symptoms were recovered to preoperative levels in 2 weeks. No patients died after surgery. No stroke or transient ischemic attack occurred. The average follow-up of was 4.2 months, no worsening of condition, recurrence or death occurred. The results indicate that for patients with subacute or chronic middle cerebral artery (M1) occlusion, mechanical recanalization was technically feasible under the premise of strict case screening. Mechanical recanalization is able to improve ischemic symptoms and promote dysfunction restoration. But its long-term effect remains to be evaluated by further large samples, long-term follow-up studies. PMID:26885148

  20. Assessment of risk of carotid occlusion with balloon Matas testing and dynamic computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Terada, Tomoaki; Okuno, Takashi; Moriwaki, Hiroshi; Nakai, Ekini; Nishiguchi, Takashi; Hayashi, Seiji; Komai, Norihiko.

    1988-02-01

    Temporary occlusion of the internal carotid artery with a balloon catheter (balloon Matas test) and simultaneous dynamic computed tomographic scanning (DCT) were performed in four patients with intracranial aneurysms to determine their tolerance for permanent carotid occlusion. Five DCT parameters were evaluated: appearance time, peak time, peak height fitting, first effective moment, and transit time. The patients were characterized into three types: type I (2 patients) - lack of neurological deficit during the balloon Matas test and equally preserved cerebral blood flow (CBF) in the two hemispheres on DCT during carotid occlusion, type II (one patient) - a decreased CBF on the occluded side on DCT despite the lack of neurological deficit; type III (one patient) - neurological signs, such as disturbance of consciousness, aphasia, and right hemiparesis occuring immediately after the start of the balloon Matas test, and a decreased CBF in the region of the middle and anterior cerebral arteries on the occluded side. In the type III patient, occlusion of the internal carotid artery is contraindicated unless an EC-IC bypass procedure that can rapidly provide a large supply of blood is performed. It can be concluded that the balloon Matas/DCT method offers a reliable means of predicting the risk of carotid ligation. (Namekawa, K.).

  1. Southeast Region Headboat Survey-Vessel list/Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of vessels that have been on the SRHS through time, their owners/operators, marinas/docks and their contact information. This assists in...

  2. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  3. Dethrombosis of the lower extremity arteries using the power-pulse spray technique in patients with recent onset thrombotic occlusions: results of the DETHROMBOSIS Registry.

    Science.gov (United States)

    Shammas, Nicolas W; Dippel, Eric J; Shammas, Gail; Gayton, Laura; Coiner, Denise; Jerin, Mike

    2008-10-01

    To assess the presence of thrombus using intravascular ultrasound (IVUS) and evaluate the feasibility of combined thrombolysis [power-pulse spray (P-PS)] and rheolytic thrombectomy (RT) in patients with recent-onset limb ischemia (<6 months) due to total occlusion of at least 1 infrainguinal vessel. Seventeen patients (12 women; mean age 68.3+/-10.7 years) enrolled in a prospective registry underwent IVUS imaging at baseline, after treatment with P-PS using tissue plasminogen activator and RT (AngioJet), and prior to definitive treatment of the vessel. The primary safety endpoints were major bleeding, distal embolization, vascular access complications, and renal failure. Effectiveness outcomes were (1) procedural success with a residual stenosis <30%, (2) IVUS-documented resolution of the thrombus, and (3) the combined clinical endpoint of procedure-related death, stroke, unplanned amputation, and unplanned urgent revascularization of the treated limb. At baseline, the majority of patients (16, 94.1%) had a definite thrombus identified by IVUS; in the remaining patient (6.3%), thrombus was likely to be present according to the IVUS scan. By angiography, 2 (11.8%) patients had a definite grade 3 thrombus and 5 (29.4%) patients had a grade 1 thrombus (modified TIMI scale) at baseline. IVUS data were available pre and post P-PS/RT in 16 (94.1%) patients. In 10 (62.5%), the thrombus was partially resolved; in 5 (31.25%), there was no apparent change. The thrombus appeared to have completely resolved in only 1 (6.3%) patient. Embolization occurred in 3 (17.6%) patients with no adverse clinical sequelae. The combined clinical endpoint was met in 1 (5.9%) of 17 patients. After final definitive treatment of the vessel, acute procedural success was 100%, with no angiographic filling defects seen. Thrombus is present in most if not all patients with a recent history of limb ischemia who are found to have an occluded culprit vessel. The application of the P-PS/RT led to

  4. Reactor vessel support system. [LMFBR

    Science.gov (United States)

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  5. 46 CFR 298.11 - Vessel requirements.

    Science.gov (United States)

    2010-10-01

    ... reconditioning of a Vessel as a condition for issuance of the Letter Commitment. The estimated cost of the Vessel may include escalation for the anticipated construction period of the Vessel. We may contact...

  6. 78 FR 38101 - Passenger Vessels Accessibility Guidelines

    Science.gov (United States)

    2013-06-25

    ... vessels. The proposed guidelines would afford these individuals equal opportunity to travel on passenger vessels for employment, transportation, public accommodation, and leisure. The proposed guidelines would... individuals equal opportunity to travel on passenger vessels for employment, transportation,...

  7. Numerical analysis of human dental occlusal contact

    Science.gov (United States)

    Bastos, F. S.; Las Casas, E. B.; Godoy, G. C. D.; Meireles, A. B.

    2010-06-01

    The purpose of this study was to obtain real contact areas, forces, and pressures acting on human dental enamel as a function of the nominal pressure during dental occlusal contact. The described development consisted of three steps: characterization of the surface roughness by 3D contact profilometry test, finite element analysis of micro responses for each pair of main asperities in contact, and homogenization of macro responses using an assumed probability density function. The inelastic deformation of enamel was considered, adjusting the stress-strain relationship of sound enamel to that obtained from instrumented indentation tests conducted with spherical tip. A mechanical part of the static friction coefficient was estimated as the ratio between tangential and normal components of the overall resistive force, resulting in μd = 0.057. Less than 1% of contact pairs reached the yield stress of enamel, indicating that the occlusal contact is essentially elastic. The micro-models indicated an average hardness of 6.25GPa, and the homogenized result for macroscopic interface was around 9GPa. Further refinements of the methodology and verification using experimental data can provide a better understanding of processes related to contact, friction and wear of human tooth enamel.

  8. Endovascular Management of Central Retinal Arterial Occlusion.

    Science.gov (United States)

    Agarwal, Nitin; Gala, Nihar B; Baumrind, Benjamin; Hansberry, David R; Thabet, Ahmad M; Gandhi, Chirag D; Prestigiacomo, Charles J

    2016-11-01

    Central retinal artery occlusion (CRAO) is an ophthalmologic emergency due to the sudden cessation of circulation to the inner retinal layer. Without immediate treatment, permanent blindness may ensue. Several treatment options exist, ranging from noninvasive medical management to thrombolysis. Nonetheless, ongoing debate exists regarding the best therapeutic strategy. The authors present the case of a 78-year-old woman with a medical history of hypercholesterolemia and rheumatoid arthritis who experienced complete loss of vision in her left eye. Following ophthalmologic evaluation demonstrating left CRAO, anterior chamber paracentesis was performed. Endovascular intervention was performed via local intra-arterial fibrinolysis with alteplase. Her vision returned to 20/20 following the procedure. In general, conventional therapies have not significantly improved patient outcomes. Several management options exist for CRAO. In general, conservative measures have not been reported to yield better patient outcomes as compared to the natural history of this medical emergency. Endovascular approaches are another option as observed with this case reported. In cases of CRAO, therapeutic strategies such as intra-arterial fibrinolysis utilize a local infusion of reactive tissue plasminogen activator directly at the site of occlusion via catheterization of the ophthalmic artery. Although several case series do show promising results after treating CRAO with intra-arterial fibrinolysis, further studies are required given the reports of complications.

  9. Metabolic syndrome and central retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Kosanović-Jaković Natalija

    2005-01-01

    Full Text Available Background. The accumulation of risk factors for central retinal artery occlusion can be seen in a single person and might be explained by the metabolic syndrome. Case report. We presented the case of a 52-year-old man with no light perception in his right eye. The visual loss was monocular and painless, fundoscopy showed central retinal artery occlusion and the laboratory investigation showed the raised erythrocyte sedimentation rate of 105 mm/h and the raised C-reactive protein of 22 mg/l. Specific laboratory investigations and fluorescein angiography excluded the presence of vasculitis, collagen vascular diseases, hypercoagulable state and antiphospholipid syndrome. Conclusion. The patient met all the five of the National Cholesterol Education Program (NCEP criteria for the metabolic syndrome: hypertension, abnormal lipid profile, abnormal glucose metabolism, obesity and hyperuricemia. Measurement of C-reactive protein is useful for the assessment of therapeutic systemic effect on any abnormality in the metabolic syndrome. Individual therapy for all risk factors in the metabolic syndrome is necessary to prevent complications such as cardiovascular, retinal vascular diseases and stroke.

  10. Vascular endothelial growth factor and hypoxia-inducible factor-1α gene polymorphisms and coronary collateral formation in patients with coronary chronic total occlusions

    Directory of Open Access Journals (Sweden)

    Vincent Amoah

    2016-06-01

    Full Text Available Introduction: We evaluated the association between two single nucleotide polymorphisms of the vascular endothelial growth factor gene and one of the hypoxia-inducible factor-1α gene and the degree of coronary collateral formation in patients with a coronary chronic total occlusion. Methods: Totally, 98 patients with symptomatic coronary artery disease and a chronic total occlusion observed during coronary angiography were recruited. Genotyping of two vascular endothelial growth factor promoter single nucleotide polymorphisms (−152G>A and −165C>T and the C1772T single nucleotide polymorphism of hypoxia-inducible factor-1α were performed using polymerase chain reaction and restriction fragment length polymorphism analysis. The presence and extent of collateral vessel filling was scored by blinded observers using the Rentrop grade. Results: We found no association between the vascular endothelial growth factor −152G>A, −165C>T and hypoxia-inducible factor-1α −1772C>T with the presence and filling of coronary collateral vessels. A history of percutaneous coronary intervention and transient ischaemic attack/cerebrovascular accident were associated with the presence of enhanced collateral vessel formation following binary logistic regression analysis. Conclusion: The study findings suggest that coronary collateral formation is not associated with the tested polymorphic variants of vascular endothelial growth factor and hypoxia-inducible factor-1α in patients with symptomatic coronary artery disease and the presence of a chronic total occlusion.

  11. 2011 Tug Towing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  12. 2013 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  13. Coastal Discard Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data on the type and amount of marine resources that are discarded or interacted with by vessels that are selected to report to the Southeast...

  14. 2013 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  15. SC/OQ Vessel Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data tables holding information for the Surf Clam/Ocean Quahog vessel and dealer/processor logbooks (negative and positive), as well as individual tag information...

  16. Vessel Permit System Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GARFO issues federal fishing permits annually to owners of fishing vessels who fish in the Greater Atlantic region, as required by federal regulation. These permits...

  17. 2011 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  18. 2011 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  19. 2011 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  20. 2013 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. Regulation of Blood Vessel Sprouting

    Science.gov (United States)

    Chappell, John C; Wiley, David M; Bautch, Victoria L

    2012-01-01

    Blood vessels are essential conduits of nutrients and oxygen throughout the body. The formation of these vessels involves angiogenic sprouting, a complex process entailing highly integrated cell behaviors and signaling pathways. In this review, we discuss how endothelial cells initiate a vessel sprout through interactions with their environment and with one another, particularly through lateral inhibition. We review the composition of the local environment, which contains an initial set of guidance cues to facilitate the proper outward migration of the sprout as it emerges from a parent vessel. The long-range guidance and sprout stability cues provided by soluble molecules, extracellular matrix components, and interactions with other cell types are also discussed. We also examine emerging evidence for mechanisms that govern sprout fusion with its target and lumen formation. PMID:22020130

  2. Caribbean PR Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels fishing in Puerto Rico. The catch and effort data for the entire trip are...

  3. Clinical results and radiographic appearance of the Rashkind double umbrella device in patients with occlusion of the ductus arteriosus

    Energy Technology Data Exchange (ETDEWEB)

    Galal, O. [King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia)]|[Department of Cardiovascular Diseases, MBC 16, King Faisal Specialist Hospital and Research Centre, PO Box 3354, Riyadh 11211 (Saudi Arabia); Sinner, W. von; Azhari, N.; Al-Fadley, F.; De Moor, M.; Boecker, J.; Fawzy, M.E..; Al-Halees, Z. [King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia)

    1997-12-01

    Background. The Rashkind double umbrella device for patent arterial duct occlusion has been used in many patients. Its radiographic appearance has not been sufficiently described. Objective. To present the varying radiographic appearances of the Rashkind double umbrella device on the chest X-ray. Materials and methods. The chest radiographs of 69 patients (median age 60 months; median weight 17 kg), who underwent closure of their patent arterial duct between March 1990 and August 1994, were reviewed. The following parameters were evaluated: (1) the size of the heart (cardio-thoracic ratio) and pulmonary vessels, (2) the position of the device in AP/PA and lateral projections. The results of occlusion of the patent arterial duct were also reviewed. Results. Sixty-two of 69 (90 %) pa- tients had complete occlusion after a follow-up between 2 months and 3{sup 1}/{sub 2} years. The cardio-thoracic ratio showed significant reduction at follow-up (P < 0.001). The two different size devices could be well differentiated in the AP and the lateral projection. In 14 patients (20 %) the device was in an asymmetrical position. There was no significant correlation between position of the device and success of occlusion in our material. Conclusion. Complete occlusion of the arterial duct using Rashkind double umbrella devices can be achieved in 90 % of our population. In 20 % the device will have an asymmetrical position. There is no correlation between asymmetrical position of the device in the chest radiograph and residual shunting. (orig.) With 7 figs., 12 refs.

  4. Peripheral areas of nonperfusion in treated central retinal vein occlusion as imaged by wide-field fluorescein angiography.

    Science.gov (United States)

    Spaide, Richard F

    2011-05-01

    To develop a method of imaging the retina using wide-field fluorescein angiography and use this method to investigate the areas of perfusion abnormalities in patients treated with ranibizumab for central retinal vein occlusion. Cross-sectional analysis of patients recruited to a prospective study. Patients in a prospective study of ranibizumab for central retinal vein occlusion were imaged with wide-field angiography. Fluorescein angiograms taken with the Optos P200 Scanning Laser Ophthalmoscope were obtained of the posterior portion of the eye and of the periphery through ocular steering. Resultant images of the periphery were registered to the posterior image using thin-plate spline warping. A transformation was used to measure the retinal surface area. Perfusion characteristics were compared with injection frequencies and protocol refraction visual acuity measurements. Of 22 patients imaged, 7 would be classified as nonperfused by the Central Retinal Vein Occlusion Study (CVOS) angiographic criteria. However, all patients showed confluent areas of nonperfusion in the retinal periphery ranging in size from 16 disk areas to 242 disk areas. The areas of peripheral nonperfusion were not significantly different in the Central Retinal Vein Occlusion Study-perfused group versus nonperfused group. The area of peripheral nonperfusion was not correlated with the number of injections (r = -0.13, P = 0.58), but was inversely correlated with visual acuity (r = -0.52, P = 0.013). Blood vessels at the border of the peripheral nonperfusion did not show signs of neovascular growth or profuse leakage. Angiographic mapping of the retina is possible using image-processing techniques with wide-field images. Eyes with central retinal vein occlusion develop widespread peripheral vascular obliteration in regions that are difficult to image with conventional fundus cameras. These nonperfused areas may have important implications for visual function.

  5. Pedal angiography in peripheral arterial occlusive disease: first-pass i.v. contrast-enhanced MR angiography with blood pool contrast medium versus intraarterial digital subtraction angiography.

    Science.gov (United States)

    Kos, Sebastian; Reisinger, Clemens; Aschwanden, Markus; Bongartz, Georg M; Jacob, Augustinus L; Bilecen, Deniz

    2009-03-01

    The purpose of this study was to prospectively evaluate first-pass i.v. gadofosveset-enhanced MR angiography in patients with peripheral arterial occlusive disease for visualization of the pedal arteries and stenosis or occlusion of those arteries with intraarterial digital subtraction angiography as the reference standard. Twenty patients with peripheral arterial occlusive disease (nine women, 11 men; age-range 58-83 years) were prospectively enrolled. Gadofosveset first-pass contrast-enhanced MR angiography was performed with a 1.5-T system, a dedicated foot coil, and cuff compression to the calf. Arterial segments were assessed for degree of arterial stenosis, arterial visibility, diagnostic utility, and venous contamination. Detection of vessel stenosis or occlusion was evaluated in comparison with findings at digital subtraction angiography. The unpaired Student's t test was used to test arterial visibility with the two techniques. First-pass MR angiography with gadofosveset had good diagnostic utility in 83.9% of all segments and no venous contamination in 96.8% of all segments. There was no difference between the performance of intraarterial digital subtraction angiography and that of i.v. contrast-enhanced MR angiography in arterial visibility overall (p = 0.245) or in subgroup analysis of surgical arterial bypass targets (p = 0.202). The overall sensitivity, specificity, and accuracy of i.v. gadofosveset-enhanced MR angiography for characterization of clinically significant stenosis and occlusion were 91.4%, 96.1%, and 93.9%. In the subgroup analysis, the sensitivity, specificity, and accuracy were 85.5%, 96.5%, and 92.1%. Gadofosveset-enhanced MR angiography of the pedal arteries in patients with peripheral arterial occlusive disease has arterial visibility equal to that of digital subtraction angiography and facilitates depiction of clinically significant stenosis and occlusion.

  6. Emergent revascularization of acute tandem vertebrobasilar occlusions: Endovascular approaches and technical considerations-Confirming the role of vertebral artery ostium stenosis as a cause of vertebrobasilar stroke.

    Science.gov (United States)

    Cohen, José E; Leker, Ronen R; Gomori, J Moshe; Eichel, Roni; Rajz, Gustavo; Moscovici, Samuel; Itshayek, Eyal

    2016-12-01

    Patients suffering from acute atherothrombotic occlusion of the proximal vertebral artery (VA) and concomitant basilar artery (BA) occlusion present a grim prognosis. We describe our experience in the endovascular recanalization of tandem vertebrobasilar occlusions using endovascular techniques. The BA was accessed through the normal VA (clean-road) or the occluded, thrombotic VA (dirty-road), and stentriever-based thrombectomy was performed using antegrade or reverse revascularization variants. Seven patients underwent successful stentriever-assisted mechanical thrombectomy of the BA and five sustained concomitant VA revascularization. Stroke onset to endovascular intervention initiation (time-to-treatment) ranged from 4.5-13hours (mean 8.6). In two of seven patients, the BA occlusion was approached with a 'clean-road' approach via the contralateral VA; in five of seven patients, a 'dirty-road' approach via the occluded VA was used. Mean time-to-recanalization was 66minutes (range 55-82). There were no perforations, iatrogenic vessel dissections, or other technical complications. Four patients presented mild-to-moderate disability (modified Rankin Scale [mRS] 0-3) at 3months, one remained with moderate-to-severe disability (mRS 4), and two patients died on days 9 and 23 after their strokes. Follow-up ranged from 6-45months (mean 24months). In selected patients with acute VA-BA occlusion, stentriever-based thrombectomy performed through either the patent or the occluded VA, may be feasible, effective, and safe. Clinical outcomes in these patients seem to equipoise the neurological outcome of patients with successful revascularization for isolated BA occlusion. This unique pair of occlusions confirms the role of VA ostium stenosis as a cause of vertebrobasilar stroke. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Computer modelling of anterior circulation stroke: Proof of concept in Cerebrovascular Occlusion

    Directory of Open Access Journals (Sweden)

    THANH G PHAN

    2014-09-01

    Full Text Available Background: Current literature emphasizes the role of the Circle of Willis (CoW in salvaging ischemic brain tissue but not that of leptomeningeal anastomoses (LA. We developed a computational model of the cerebral circulation to 1 evaluate the roles of the CoW and LA in restoring flow to the superficial compartment of the middle cerebral artery territory and 2 estimate the size of the LA required to maintain flow above the critical ischemic threshold (>30% of baseline under simulated occlusion. Methods: Cerebral vasculature was modelled as a network of junctions connected by cylindrical pipes. The experiments included occlusion of successive distal branches of the intracranial arteries while the diameters of LA were varied. Results: The model showed that the region of reduced flow became progressively smaller as the site of occlusion was moved from the large proximal to the smaller distal arteries. There was no improvement in flow in the MCA territory when the diameters of the inter-territorial LA were varied from 0.0625 mm to 0.5 mm while keeping the intra-territorial LA constant. By contrast, the diameter of the inter-territorial LA needed to be greater than 1.0 mm in order to provide adequate (>30% flow to selected arteries in the occluded MCA territory. Conclusions: The CoW and inter-territorial LA together play important supportive roles in intracranial artery occlusion. Computational modelling provides the ability to experimentally investigate the effect of arterial occlusion on CoW and LA function.

  8. Early rethrombosis in femoropopliteal occlusions treated with percutaneous transluminal angioplasty

    DEFF Research Database (Denmark)

    Jørgensen, B; Meisner, S; Holstein, P;

    1990-01-01

    One hundred and thirty-seven consecutive percutaneous transluminal angioplasties (PTA) were performed for femoropopliteal vascular disease including 58 stenoses and 79 total occlusions. Nine occlusions could not be crossed with the guidewire, but in the remaining 128 the haemodynamic and clinical...

  9. Sharp Recanalization for Chronic Left Iliac Vein Occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Nobutake, E-mail: nobutake@rad.med.keio.ac.jp; Isfort, Peter; Penzkofer, Tobias [RWTH Aachen University, Department of Diagnostic and Interventional Radiology, University Hospital (Germany); Grommes, Jochen; Greiner, Andreas [RWTH Aachen University, Department of Vascular Surgery, University Hospital (Germany); Mahnken, Andreas [RWTH Aachen University, Department of Diagnostic and Interventional Radiology, University Hospital (Germany)

    2012-08-15

    Endovascular treatment has emerged as a first-line treatment for venous occlusions, but is sometimes challenging with conventional approaches. This article describes a helpful technique using a Roesch-Uchida needle to cross a chronic occlusion of the iliac vein when conventional techniques have failed.

  10. Determination of occlusal facial height in oral reconstructive procedures.

    Science.gov (United States)

    L'Estrange, P R; Rowell, J

    1992-01-01

    A review is provided of the methods that have been employed for the determination of occlusal facial height in oral reconstructive procedures. Details are provided in relation to a modified form of the patient's own assessment of a preferred vertical dimension of occlusion (PVDO) in dentate subjects exhibiting overclosure, edentulous subjects and in those patients requiring full mouth oral rehabilitation.

  11. Varying face occlusion detection and iterative recovery for face recognition

    Science.gov (United States)

    Wang, Meng; Hu, Zhengping; Sun, Zhe; Zhao, Shuhuan; Sun, Mei

    2017-05-01

    In most sparse representation methods for face recognition (FR), occlusion problems were usually solved via removing the occlusion part of both query samples and training samples to perform the recognition process. This practice ignores the global feature of facial image and may lead to unsatisfactory results due to the limitation of local features. Considering the aforementioned drawback, we propose a method called varying occlusion detection and iterative recovery for FR. The main contributions of our method are as follows: (1) to detect an accurate occlusion area of facial images, an image processing and intersection-based clustering combination method is used for occlusion FR; (2) according to an accurate occlusion map, the new integrated facial images are recovered iteratively and put into a recognition process; and (3) the effectiveness on recognition accuracy of our method is verified by comparing it with three typical occlusion map detection methods. Experiments show that the proposed method has a highly accurate detection and recovery performance and that it outperforms several similar state-of-the-art methods against partial contiguous occlusion.

  12. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik;

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  13. Comorbidity in patients with branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Linneberg, Allan René; Rosenberg, Niels 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....

  14. Treatment strategies for extensive chronic SFA occlusions: indications and results.

    NARCIS (Netherlands)

    Lensvelt, M.M.A.; Reijnen, M.M.P.J.; Wallis de Vries, B.M.; Zeebregts, C.J.A.

    2012-01-01

    Treatment modalities for extensive chronic occlusive disease of the superficial femoral artery (SFA) have changed during the last decades. In this chapter we provide an overview of current treatment modalities for extensive chronic occlusive disease of the SFA. Although the autologous venous conduit

  15. Treatment strategies for extensive chronic SFA occlusions : indications and results

    NARCIS (Netherlands)

    Lensvelt, M. M. A.; Reijnen, M. M. P. J.; De Vries, B. M. Wallis; Zeebregts, C. J.

    2012-01-01

    Treatment modalities for extensive chronic occlusive disease of the superficial femoral artery (SFA) have changed during the last decades. In this chapter we provide an overview of current treatment modalities for extensive chronic occlusive disease of the SFA. Although the autologous venous conduit

  16. Cognitive impairments in patients with cerebrovascular steno-occlusive disease

    Institute of Scientific and Technical Information of China (English)

    石丹

    2012-01-01

    Objective To explore the relationship between cerebrovascular steno-occlusive disease and neuropsychological performance by cognitive function assessment. Methods Using a case-control study,45 patients with cerebrovascular steno-occlusive lesions (patient group) and 59 control subjects without cerebrovascular

  17. Relationship between retinal vascular occlusions and incident cerebrovascular diseases

    Science.gov (United States)

    Zhou, Yue; Zhu, Wengen; Wang, Changyun

    2016-01-01

    Abstract Several studies investigating the role of retinal vascular occlusions, on cerebrovascular diseases (CVD) have been reported, but the results are still inconsistent. We therefore sought to evaluate the relationship between retinal vascular occlusions and CVD. We systematically searched the Cochrane Library, PubMed, and ScienceDirect databases through January 31, 2016 for studies evaluating the effect of retinal vascular occlusions on the risk of CVD. Data were abstracted using predefined criteria, and then pooled by RevMan 5.3 software. A total of 9 retrospective studies were included in this meta-analysis. When compared with individuals without retinal vascular occlusions, both individuals with retinal artery occlusion (RAO) (odds ratio [OR] = 2.01, 95% confidence interval [CI]: 1.21–3.34; P = 0.005) and individuals with retinal vein occlusion (RVO) (OR = 1.37, 95% CI: 1.24–1.50; P < 0.00001) had higher risks of developing CVD. Additionally, both individuals with central retinal artery occlusion (CRAO) (OR = 2.00, 95% CI: 1.12–3.56; P = 0.02) and branch retinal artery occlusion (BRAO) (OR = 1.60, 95% CI: 1.03–1.48; P = 0.04) were significantly associated with increased risk of CVD. Published literatures support both RVO and RAO are associated with increased risks of CVD. Further prospective studies are needed to confirm these findings. PMID:27368050

  18. Occlusion and functional disorders of the masticatory system.

    Science.gov (United States)

    Okeson, J P

    1995-04-01

    Understanding the relationship between occlusion and functional disorders of the masticatory system is no easy task. This article explores the static, functional, and dynamic relationships of the occlusal condition to the signs and symptoms of masticatory dysfunction. Some possible relationships are discussed.

  19. Characteristics, Detection Methods and Treatment of Questionable Occlusal Carious Lesions

    DEFF Research Database (Denmark)

    Makhija, S.K.; Gilbert, G.H.; Funkhouser, E.

    2014-01-01

    Questionable occlusal carious lesions (QOC) can be defined as an occlusal tooth surface with no cavitation and no radiographic radiolucencies, but caries is suspected due to roughness, surface opacities or staining. An earlier analysis of data from this study indicates 1/3 of patients have a QOC...

  20. Retino-choroidal ischemia in central retinal vein occlusion

    OpenAIRE

    Hussain, Nazimul; Hussain, Anjli

    2014-01-01

    A 41-year-old gentleman with insulin dependent diabetes had decreased vision in the right eye due to non-ischemic central retinal vein occlusion with macular edema. One month following intravitreal ranibizumab, he developed retino-choroidal ischemia with further loss of vision. Authors show the fluorescein angiographic transition from non-ischemic central retinal vein occlusion to retino-choroidal ischemia.