Search results for "Collateral"

Whole-body MRI in patients with lymphoma: collateral findings.

2016

To assess the incidence of collateral findings detected on whole-body magnetic resonance (WB-MRI) scans performed on patients with lymphoma. 114 patients (65 male; median age 45.2 years, range 15–86) with histologically confirmed lymphoma (47 Hodgkin, 67 Non-Hodgkin) underwent WB-MRI. The collateral findings were classified into three classes, according to their clinical significance, as follows: not or low significant (class 1), moderately or potentially significant (class 2), and significant (class 3). A Chi-square (χ 2) test was performed to assess the statistical significance of differences in the incidence of collateral findings based on age (≤50 and >50 years old), gender and histolog…

Evaluation of collateral flow capacity in patients with vascular or tumorous lesions of the skull base by Doppler sonography

1991

In 12 patients with vascular or tumorous lesions of the skull base, the collateral flow capacity was examined by transcranial Doppler sonography and carotid compression studies. In four patients no cross flow mechanism was found, in two patients the test remained unclear, and in six patients the examination suggested a good collateral flow capacity. However, for this application of Doppler sonography no borderlines have yet been defined and thus interpretation is difficult. Intraoperative Doppler sonography was used in five patients and proved to be helpful for localisation of the internal carotid artery within skull base tumors.

Valutazione dell’efficacia e della sicurezza dei sistemi di riduzione endoscopica di volume polmonare nel trattamento dell’enfisema polmonare

2014

Recanalization of Totally Occluded Coronary Vessels by Percutaneous Transluminal Coronary Angioplasty

1986

Since its introduction in 1977, percutaneous transluminal coronary angioplasty (PTCA) has become an effective approach for treatment of patients with single-vessel disease [1–3, 5]. Treatment of double- and multiple-vessel disease has also been attempted [5, 6]. In patients with angina pectoris total occlusion of coronary vessels is found, and PTCA has also been used in an attempt to restore coronary blood flow in such patients [8, 10]. Even main stem occlusions have been recanalized [11]. In patients with total occlusion of coronary vessels, collateral flow is sufficient to maintain cardiac function at rest but not during exercise [12–14]. Therefore, PTCA seems to be an ideal method for re…

“The importance of being external”: review of the literature of the rare phenomenon of common carotid occlusion with bulb reverse-crossed stenosis an…

2022

Common carotid artery occlusion (CCAO) is a rare phenomenon associated with the development of neurological symptoms. In CCAO, diversion of blood flow from the external carotid artery (ECA) to the internal carotid artery (ICA) via the carotid bulb (CB) may occur. This pathway activation has been called "carotid steal". Starting from a particular case we describe the ECD finding of a complete occlusion of CCA with patency of ICA and ECA. In case of occlusion of CCA, inversion of the ECA flow may occur, towards the ICA, and it can be damped by a significant stenosis crossed in retrograde direction that may concur to maintain the pressure balance between the two circulations. Usually, this par…

Channel Tracking Guidewire and Technique for Retrograde Approach

2020

Evaluation of the collateral circulation is critical for determining the feasibility of the retrograde approach. When assessing collateral channels it is of paramount importance to take time and review the previous angiogram carefully, for multiple potential collateral pathways, as the predominant collateral may change over time prior to the procedure. Careful review of collaterals prior to the procedure can reduce contrast and radiation dose as well as the duration of the procedure.Retrograde access to the distal vessel can be achieved via septal collaterals, epicardial collaterals (atrial channel), or (patent or occluded) coronary bypass grafts. Generally septals are used more often 65–70…

Collateral Sensitivity in Drug-Resistant Tumor Cells

2013

Collateral sensitivity is a term for the hypersensitivity of otherwise drug-resistant cells. The selective killing of tumor cells by drugs exerting collateral sensitivity might be used as a novel treatment strategy. In this chapter, we give an overview on drug resistance phenotypes with known collateral sensitivities; furthermore, their molecular and cellular mechanisms were discussed to explain mediation of these hypersensitivities.

Critical single proximal left arterial descending coronary artery stenosis to mimic chronic myocardial ischemia: a new model induced by minimal invas…

2008

<i>Background/Aims:</i> The present report examines a new pig model for progressive induction of high-grade stenosis, for the study of chronic myocardial ischemia and the dynamics of collateral vessel growth. <i>Methods:</i> Thirty-nine Landrace pigs were instrumented with a novel experimental stent (GVD stent) in the left anterior descending coronary artery. Eight animals underwent transthoracic echocardiography at rest and under low-dose dobutamine. Seven animals were examined by nuclear PET and SPECT analysis. Epi-, mid- and endocardial fibrosis and the numbers of arterial vessels were examined by histology. <i>Results:</i> Functional analysis showed a…

Older adult psychopathology: international comparisons of self-reports, collateral reports, and cross-informant agreement

2020

ABSTRACTObjectives:To conduct international comparisons of self-reports, collateral reports, and cross-informant agreement regarding older adult psychopathology.Participants:We compared self-ratings of problems (e.g. I cry a lot) and personal strengths (e.g. I like to help others) for 10,686 adults aged 60–102 years from 19 societies and collateral ratings for 7,065 of these adults from 12 societies.Measurements:Data were obtained via the Older Adult Self-Report (OASR) and the Older Adult Behavior Checklist (OABCL; Achenbach et al., 2004).Results:Cronbach’s alphas were .76 (OASR) and .80 (OABCL) averaged across societies. Across societies, 27 of the 30 problem items with the highest mean ra…

Banking Competition, Housing Prices and Macroeconomic Stability

2012

We develop a dynamic general equilibrium model with an imperfectly competitive bank-loans market and collateral constraints that tie investors credit capacity to the value of their real estate holdings. Banks set optimal lending rates taking into account the effects of their price policies on their market share and on the volume of funds demanded by each customer. Lending margins have a significant effect on aggregate variables. Over the long run, fostering banking competition increases total consumption and output by triggering a reallocation of available collateral towards investors. However, as regards the short-run dynamics, we find that most macroeconomic variables are more responsive …