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Occlusive Disease (occlusive + disease)
Kinds of Occlusive Disease Selected Abstracts"Cracking and Paving": A Novel Technique to Deliver a Thoracic Endograft Despite Ilio-Femoral Occlusive DiseaseJOURNAL OF CARDIAC SURGERY, Issue 2 2009Jacques Kpodonu M.D. High-risk surgical patients with ilio-femoral occlusive disease may not be amenable to general anesthesia and the construction of a retroperitoneal conduit. Methods and Results: We report the use of a novel technique consisting of cracking and paving of the ilio-femoral vessels with balloon angioplasty, followed by deployment of an endoconduit to deliver an endoluminal graft under local sedation to treat a high-risk 80-year-old patient with a thoracic aneurysm. Conclusion: High-risk surgical patients with iliofemoral disease can undergo endoluminal graft therapy to threat thoracic aortic aneurysms. [source] Hemodynamic Effects of Innominate Artery Occlusive Disease on Anterior Cerebral ArteryJOURNAL OF NEUROIMAGING, Issue 1 2002Teng-Yeow Tan MD Stenoses of the innominate artery (IA) may affect flow conditions in the carotid arteries. However, alternating flow in ipsilateral anterior cerebral artery (ACA) due to IA stenosis is extremely rare. A 49-year-old woman who was evaluated for symptomatic cerebrovascular disease presented with right latent subclavian and right carotid system steal. Transcranial Doppler examination displayed systolic deceleration wave-forms in the right terminal internal carotid artery and alternating flow in the right ACA. Magnetic resonance angiography demonstrated tight stenosis of the right IA. For a thorough study of the hemodynamic effects of IA stenosis, a combination of duplex and transcranial Doppler examination is required. [source] Obliterating intracranial vasculopathy mimicking multiple sclerosisACTA NEUROLOGICA SCANDINAVICA, Issue 1 2009M. Boentert Background,,, The first ever diagnosis of multiple sclerosis (MS) requires consideration of both diagnostic criteria and differential diagnosis. Clinicians are particularly challenged by rare conditions which may mimic MS symptoms and relapses. Case report,,, We report the case of a young female patient who presented with relapsing left hemispheric symptoms that were highly suspicious of MS but were caused by an idiopathic occlusive angiopathy of the circle of Willis. Conclusion,,, Occlusive disease of the great cerebral arteries in young patients is a rare but important differential diagnosis of MS. It has to be considered in patients presenting with the first symptoms suspicious of MS as substantial treatment consequences will arise. [source] Etiology of strokes in children with sickle cell anemiaDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2006Michael R. DeBaun Abstract The most devastating complication of sickle cell anemia is cerebral infarction, affecting ,30% of all individuals with sickle cell anemia. Despite being one of the most common causes of stroke in infants and children, the mechanism of cerebral infarction in this population has not been extensively studied and is poorly understood. Multiple, synergistic factors are important in the pathogenesis of stroke including the hemodynamic effects of cerebral arterial occlusive disease, viscosity, chronic and acute anemia and acute medical events. This review focuses on the relationship between these factors in order to provide a foundation for further study of the etiology of strokes in this high-risk population. MRDD Research Reviews 2006;12:192,199. © 2006 Wiley-Liss, Inc. [source] Higher arterial stiffness, greater peripheral vascular resistance and lower blood flow in lower-leg arteries are associated with long-term hyperglycaemia in type 2 diabetic patients with normal ankle-brachial indexDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 4 2009Eiji Suzuki Abstract Background Higher arterial stiffness and greater peripheral vascular resistance reduce blood flow in lower-leg arteries and contribute to the development of ischaemic limb in diabetic patients even without peripheral artery occlusive disease. The aim of this study was to clarify whether these vascular parameters are associated with long-term hyperglycaemia in diabetic patients. Methods We examined 45 type 2 diabetic patients and 38 age-matched nondiabetic subjects without peripheral artery occlusive disease assessed by ankle-brachial index consecutively admitted to our hospital, and followed them over a 3-year period (3.7 ± 0.7 years) with no vasodilative medication. Blood flow and resistive index, a measure of peripheral vascular resistance, at the popliteal artery were evaluated using gated two-dimensional cine-mode phase-contrast magnetic resonance imaging. Brachial-ankle pulse wave velocity was measured to assess arterial stiffness. Results At baseline, consistent with our previous report, diabetic patients showed higher brachial-ankle pulse wave velocity (p < 0.0001) and resistive index (p < 0.0001) and lower flow volume (p = 0.0044) than those of nondiabetic subjects. Stepwise multiple regression analysis revealed that duration of diabetes, mean HbA1c during the study, use of renin-angiotensin system inhibitors and change per year in resistive index were identified as significant independent variables predicting change per year in blood flow (r2 = 0.733, p < 0.0001) in diabetic patients. Mean HbA1c during the study was positively correlated with changes per year in brachial-ankle pulse wave velocity (p = 0.00007) and resistive index (p = 0.0014) and was negatively correlated with that in blood flow (p < 0.0001) in diabetic patients. Conclusions Long-term hyperglycaemia is a major cause of impaired peripheral circulation in lower-leg arteries in diabetic patients without peripheral artery occlusive disease. Copyright © 2009 John Wiley & Sons, Ltd. [source] The influence of exercise on foot perfusion in diabetesDIABETIC MEDICINE, Issue 10 2007D. T. Williams Abstract Aims, Diabetic foot disease is associated with both macro- and microvascular disease. Exercise has both positive and negative effects on the perfusion of lower limbs with peripheral arterial occlusive disease (PAOD). We aimed to measure changes in foot perfusion following a brief period of lower-limb exercise in individuals with and without Type 2 diabetes and non-critical PAOD. Methods, Subjects were allocated to groups according to the presence or absence of diabetes, PAOD on colour duplex imaging and clinically detectable peripheral neuropaÍthy. Transcutaneous oxygen tension (TcPO2), transcutaneous carbon dioxide tension (TcPCO2), ankle-brachial pressure indices, toe pressures and toe-brachial pressure indices (TBI) were measured. Results, One hundred and sixteen limbs were studied in 61 subjects. Post-exercise, toe pressure and TBI increased in the non-diabetic group with arterial disease, but not in the groups with diabetes. Foot TcPO2 values increased in groups with diabetes and TcPCO2 decreased in all groups with arterial disease. Increased chest TcPO2 and decreased TcPCO2 were demonstrated in the groups with diabetes. Conclusions, Elevations in foot TcPO2 and reductions in TcPCO2 indicate improved cutaneous perfusion response to local heating post-exercise. Elevated toe pressures in the non-diabetes group suggest that improved perfusion may be associated with enhanced lower limb macrovascular haemodynamics. However, improvements in TcPO2 and TcPCO2 at foot and chest sites in diabetes imply a global change in cutaneous perfusion. The results suggest that brief exercise results in an improvement in cutaneous perfusion in non-critical PAOD, particularly in individuals with diabetes. [source] Long-term follow-up of patients with asymptomatic occlusion of the internal carotid artery with good and impaired cerebral vasomotor reactivityEUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2010I. Kimiagar Background:, Cerebral hemodynamic status might be prognostic for either the symptomatic or asymptomatic course of carotid occlusive disease. It is determined by evaluating cerebral vasomotor reactivity (VMR). We assessed VMR in asymptomatic patients with total occlusion of the internal carotid artery (ICA) and followed them to evaluate the role of impaired VMR in predicting ischaemic stroke (IS). Methods:, Thirty-five patients (21 men, mean age ± SD 68 ± 7.5 years) with unilateral asymptomatic ICA occlusion were studied by transcranial Doppler and the Diamox test (intravenous 1.0 g acetazolamide) and followed for 48 months or until reaching the end-points of IS, transient ischaemic attack, or vascular death. VMR% was evaluated by recording the percent differences in peak systolic blood flow velocities in each middle cerebral artery at baseline and after Diamox administration. Results:, Based on VMR% calculations, 14 (40%) patients had good VMRs and 21 (60%) had impaired VMRs. The global annual risk of ipsilateral ischaemic events was 5.7%. The annual ipsilateral ischaemic event risk was 1.8% in patients with good VMRs, whilst it was 7.1% in patients with impaired VMRs. An impaired VMR was significantly correlated with ipsilateral IS (Kaplan,Meier log rank statistic, P = 0.04). Conclusions:, Our results support the value of VMR assessment for identifying asymptomatic patients with carotid occlusion who belong to a high-risk subgroup for IS. New trials using extracranial-to-intracranial bypass surgery in patients with asymptomatic ICA occlusion and impaired VMRs are warranted. [source] Revascularization in acute ischaemic stroke using the penumbra system: the first single center experienceEUROPEAN JOURNAL OF NEUROLOGY, Issue 11 2009I. Q. Grunwald Background and purpose:, This is the first single center experience illustrating the effectiveness of the penumbra system (PS) in the treatment of large vessel occlusive disease in the arena of acute ischaemic stroke. The PS is an innovative mechanical thrombectomy device, employed in the revascularization of large cerebral vessel occlusions in patients via the utilization of an aspiration platform. Methods:, This is a prospective, non-randomized controlled trial evaluating the clinical and functional outcome in 29 patients with acute intra-cranial occlusions consequent to mechanical thrombectomy by the PS either as mono-therapy or as an adjunct to current standard of care. Patients were evaluated by a neurologist and treated by our in house interventional neuro-radiologists. Primary end-points were revascularization of the occluded target vessel to TIMI grade 2 or 3 and neurological outcome as measured by an improvement in the NIH Stroke Scale (NIHSS) score after the procedure. Results:, Complete revascularization (TIMI 3) was achieved in 21/29 (72.4%) of patients. Partial revascularization (TIMI 2) was established in 4/29 (13.8%) of patients. Revascularization failed in four (13.8%) patients. Nineteen (19) patients (65.5%) had at least a four-point improvement in NIHSS scores. Modified Rankin scale scores of ,2 were seen in 37.9% of patients. There were no device-related adverse events. Symptomatic intra-cranial hemorrhage occurred in 7% of patients. Conclusions:, The PS has the potential of exercising a significant impact in the interventional treatment of ischaemic stroke in the future. [source] Cerebral vasomotor reactivity of bilateral severe carotid stenosis: is stroke unavoidable?EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2006A. Y. Gur We evaluated the cerebral hemodynamic features of severe bilateral carotid stenosis by assessing and comparing cerebral vasomotor reactivity (VMR) in the middle cerebral (MCA) and vertebral arteries (VA) by transcranial Doppler and the Diamox (1 g acetazolamide i.v.) test. VMR was evaluated by recording the percentage differences in peak systolic blood flow velocity in each MCA and VA at baseline and by the Diamox test. Twenty-eight symptomatic (SCAS) and 31 asymptomatic (ACAS) patients with bilateral severe (>70%) internal carotid artery stenosis were studied. The mean MCA VMR% was 29 ± 26.9% in SCAS and 43.2 ± 26.8% in ACAS patients (P < 0.01). Their respective mean VA VMR% was 30.2 ± 36.5% and 39.6 ± 24.4% (P = NS). VMR% of the symptomatic MCA side in SCAS patients was significantly lower than the opposite side (20.5 ± 31.1% and 39.2 ± 37.9% respectively; P < 0.03). In contrast, the VA VMR% of both sides in SCAS patients remained similar (28.1 ± 39.3% and 34.6 ± 47.9% respectively; P = NS). VMR% of the MCA and VA in ACAS patients was also similar for both sides of bilateral carotid stenosis. The cerebral hemodynamic features differ between SCAS and ACAS patients with bilateral carotid occlusive disease in the anterior part of the circle of Willis. An independent cerebral vascular reserve capacity of the posterior circulation is proposed. [source] Antimicrobial therapy in DermatologyJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 1 2006Cord Sunderkötter Antiseptika; Antibiotika; ,-Laktam-Resistenz; Weichteilinfektion Summary The extensive and sometimes indiscriminate use of antibiotics sometimes without strict indications has led to increases in both bacterial resistance and sensitization of patients. Systemic antibiotics in skin infections are indicated when a severe local infection occurs which spreads into the surrounding tissue or when there are signs of systemic infection. There are special indications in patients with peripheral arterial occlusive disease,diabetes or immunosuppression. Topical use of antibiotics should be abandoned and replaced by antiseptics. The ,-lactam antibiotics are the antibiotics of first choice for many skin infections. They are usually effective, have a well-defined profile of adverse events and most are affordable. Penicillin G or V are the first line treatment for erysipelas. Infections with Staphylococcus aureus are usually treated with isoxazolyl penicillins or second generation cephalosporins. In mixed infections in patients with diabetes or peripheral arterial occlusive disease,the treatment of choice is metronidazole plus ,-lactam-/,-lactamase inhibitor antibiotics, but quinolones or second generation cephalosporins can also be used, once again with metronidazole. The aim of this review is to define the indications for antibiotics in dermatology, to highlight their modes of action and adverse effects and to make suggestions for rational antibiotic therapy in cutaneous infections frequently encountered in the practice of dermatology. Zusammenfassung Der bisweilen unkritische Einsatz von Antibiotika hat die Resistenzentwicklung beschleunigt und die Sensibilisierungsrate bei Patienten erhöht. Systemische Antibiotika sind bei kutanen Superinfektionen in der Regel dann indiziert, wenn eine schwere lokale Infektion mit Ausbreitung in das umgebende Gewebe vorliegt oder wenn sich gleichzeitig Zeichen einer systemischen Infektion einstellen. Bei peripherer arterieller Verschlusskrankheit, Diabetes mellitus oder Immunsuppression kann die Indikation auch früher gestellt werden. Lokale Antibiotika sollten in der Regel gemieden und durch moderne Antiseptika ersetzt werden. ,-Laktam-Antibiotika stellen für viele bakterielle Infektionserkrankungen in der ambulanten und klinischen Dermatologie die Antibiotika der ersten Wahl dar. Sie sind häufig ausreichend wirksam, besitzen ein gut definiertes Nebenwir-kungsprofil und sind zumeist preisgünstig. So wird das klassische Streptokokken-Erysipel mit Penicillin G oder V therapiert, bei Infektionen durch S. aureus kommen primär Isoxazolyl-Penicilline oder Zweit-Generations-Cephalosporine zum Einsatz. Im Falle von Mischinfektionen bei Diabetes mellitus oder pAVK sind ,-Laktam/,-Laktamaseinhibitoren indiziert, alternativ auch Chinolone oder Zweitgenerations-Cephalosporine, jeweils in Kombination mit Metronidazol. Diese Übersicht möchte die Indikationen für Antibiotika in der Dermatologie aufzeigen, das Wichtigste zu deren Wirkungsweise und Nebenwirkungen aufzählen und Therapievorschläge für häufige Infektionen der Haut in der dermatologischen Praxis geben. [source] "Cracking and Paving": A Novel Technique to Deliver a Thoracic Endograft Despite Ilio-Femoral Occlusive DiseaseJOURNAL OF CARDIAC SURGERY, Issue 2 2009Jacques Kpodonu M.D. High-risk surgical patients with ilio-femoral occlusive disease may not be amenable to general anesthesia and the construction of a retroperitoneal conduit. Methods and Results: We report the use of a novel technique consisting of cracking and paving of the ilio-femoral vessels with balloon angioplasty, followed by deployment of an endoconduit to deliver an endoluminal graft under local sedation to treat a high-risk 80-year-old patient with a thoracic aneurysm. Conclusion: High-risk surgical patients with iliofemoral disease can undergo endoluminal graft therapy to threat thoracic aortic aneurysms. [source] LDL-apheresis up-regulates VEGF and IGF-I in patients with ischemic limbJOURNAL OF CLINICAL APHERESIS, Issue 3 2003Shuzo Kobayashi Abstract Although it is known that LDL-apheresis improves ischemic limb seen in patients with peripheral arterial occlusive disease (PAOD), the underlying mechanism(s) still remains unknown. We studied whether vascular endothelial growth factor (VEGF) and/or insulin-like growth factor-I (IGF-I) levels correlated with improvement of ischemic limbs after LDL-apheresis. Sixteen patients with PAOD (13 men, 3 women) were enrolled in our study. LDL-apheresis was performed 10 times (treated plasma 3,000 ml) for 5 weeks. Serum level of VEGF significantly increased from 262 ± 171 pg/ml to 306 ± 165 pg/ml before and after LDL-apheresis (P < 0.05). This value further increased up to 441 ± 175 pg/ml 3 months after the end of this therapy (P < 0.01, compared with the basal value and P < 0.05, compared with the value at the end of 10-times session). Increased levels of VEGF paralleled increases in the ankle-brachial pressure index (ABI). After 10-times therapy, IGF-I significantly decreased (P < 0.05), but increased over the basal value 3 months after this therapy. Plasma fibrinogen statistically decreased and remained low for 3 months. The favorable effects of LDL-apheresis may be ascribed to up-regulation of VEGF and IGF-I associated with decreased fibrinogen levels. J. Clin. Apheresis, 18:115,119, 2003. © 2003 Wiley-Liss, Inc. [source] Diagnosis of arterial occlusive disease of the upper extremities: Comparison of color duplex sonography and angiographyJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2003Muharrem Tola MD Abstract Purpose The aim of this study was to assess the abilities of color duplex sonography (CDUS) to detect and characterize arterial occlusive disease of the upper extremities. Methods We prospectively compared the results of CDUS with those of intra-arterial digital subtraction angiography, which were considered definitive, in patients with symptomatic arterial occlusive disease of the upper extremities. In each extremity, we visualized 9 arterial segments, which were each evaluated for stenoses and occlusions. Each segment was categorized on each imaging modality as not significantly narrowed (narrowed by <50%), significantly narrowed (narrowed by ,50% but <100%), or occluded (100%). Results We examined a total of 578 segments in 57 patients (34 men and 23 women) with a mean age of 50 years (range, 20,74 years). CDUS had a sensitivity, a specificity, a positive predictive value, a negative predictive value, and an accuracy of 98%, 99%, 97%, 99.5%, and 99%, respectively, for detecting occluded lesions and 79%, 100%, 100%, 99%, and 99%, respectively, for detecting hemodynamically significantly stenotic lesions. Notably, the sensitivity of CDUS for diagnosing significantly stenotic lesions (79%) was lower than that for diagnosing occlusive disease (98%). Conclusions With high sensitivity and accuracy rates, CDUS is a reliable screening method for detecting arterial occlusive disease of the upper extremities. This modality efficiently provides anatomic and hemodynamic data that are useful in cases of such disease. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:407,411, 2003 [source] Pro-inflammatory genetic profiles in subjects with peripheral arterial occlusive disease and critical limb ischemiaJOURNAL OF INTERNAL MEDICINE, Issue 1 2007A. Flex Abstract. Objectives., Single nucleotide polymorphisms in genes encoding inflammatory molecules may determine genetic profiles associated with increased risk of development and progression of cardiovascular diseases. In this study, we evaluated distribution and reciprocal interaction of a set of functionally important polymorphisms of genes encoding prototypical inflammatory molecules in subjects with peripheral arterial occlusive disease (PAOD) and critical limb ischemia (CLI). We also investigated whether synergistic interactions between these pro-inflammatory gene polymorphisms influence the risk of PAOD and CLI. Design, subjects and methods., In a genetic association study that included 157 PAOD patients and 206 controls, the following gene polymorphisms were analysed: C-reactive protein (CRP) 1059 G/C, interleukin-6 (IL-6)-174 G/C, macrophage migration inhibitory factor (MIF)-173 G/C, monocyte chemoattractant protein (MCP-1) , 2518 A/G, E-selectin (E-Sel) Ser128Arg, intercellular adhesion molecule-1 (ICAM-1) 469 E/K, matrix metalloproteinase (MMP),1 -1607 1G/2G, MMP-3 -1171 5A/6A and MMP-9 -1563 C/T. Results:, We found that IL-6, E-sel, ICAM-1, MCP-1, MMP-1 and MMP-3 gene polymorphisms were significantly and independently associated with PAOD. We also found that these pro-inflammatory polymorphisms determine genetic profiles that are associated with different levels of risk for PAOD and CLI, depending on the number of high-risk genotypes concomitantly carried by a given individual. Conclusions:, Pro-inflammatory genetic profiles are significantly more common in subjects with PAOD. Synergistic effects between pro-inflammatory genotypes might be potential markers for the presence and severity of atherosclerotic disorders. [source] Diagnostic Coronary Angiography in Patients with Peripheral Arterial Disease: A Sub-study of the Coronary Artery Revascularization Prophylaxis TrialJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2008SANTIAGO GARCIA M.D. Background: Although patients in need of elective vascular surgery are often considered candidates for diagnostic coronary angiography, the safety of this invasive study has not been systematically studied in a large cohort of patients scheduled for an elective vascular operation. The goal of this sub-study of the Coronary Artery Revascularization Prophylaxis (CARP) trial was to assess the safety of coronary angiography in patients with peripheral vascular disease. Methods: The CARP trial tested the long-term benefit of coronary artery revascularization prior to elective vascular operations. Among those patients who underwent diagnostic coronary angiography during screening for the trial, the associated complications were determined at 24 hours following the diagnostic procedure. Results: Over 5,000 patients were screened during a 4-year recruitment period at 18 major VA medical centers and the present cohort consists of 1,298 patients who underwent preoperative coronary angiography. Surgical indications for vascular surgery included an expanding aortic aneurysm (AAA) (n = 446; 34.4%) or arterial occlusive disease with either claudication (n = 457; 35.2%) or rest pain (n = 395; 30.4%). A total of 39 patients had a confirmed complication with a major complication identified in 17 patients (1.3%). Complication rates were higher in patients with arterial occlusive symptoms compared with expanding aneurysms (1.8% vs. 0.5%; P = 0.07) and were not dissimilar with femoral (2.8%) versus nonfemoral (4.7%) access sites (P = 0.42). Conclusions: Coronary angiography is safe in patients with peripheral arterial disease undergoing preoperative coronary angiography. The complication rate is higher in patients with symptoms of arterial occlusive disease. [source] Extracranial Vertebral Artery InterventionJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2007DEBABRATA MUKHERJEE M.D. Atherosclerosis is the commonest cause of vertebral artery stenosis and has a predilection for the origin and proximal section of the extracranial portion of the vessel and also the intracranial portion of the vessel. Although it has generally been thought that extracranial vertebral artery (ECVA) disease has a more benign outcome compared to intracranial vertebral artery disease, significant occlusive disease of the proximal vertebral artery is the primary cause of vertebral artery ischemia in a significant proportion of patients. We focus on the interventional management of patients with proximal ECVA disease in this article. [source] Whole-body MR angiography using a novel 32-receiving-channel MR system with surface coil technology: First clinical experienceJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2005Michael Fenchel MD Abstract Purpose To demonstrate the feasibility of detecting atherosclerotic vascular disease using an innovative magnetic resonance angiography (MRA) protocol in combination with a dedicated whole-body MR scanner with new surface coil technology. Materials and Methods A total of 10 volunteers and eight patients with peripheral arterial occlusive disease (PAOD) were examined at 1.5 T. Conventional digital subtraction angiography (DSA) of the symptomatic region was available as a reference standard in all eight patients. Depending on subjects' size, four to five three-dimensional data sets were acquired using an adapted injection protocol. Images were assessed independently by two readers for vascular pathology. Additionally, signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were measured. Results Whole-body MRA yielded excellent sensitivity and specificity of more than 95% for both readers with high interobserver agreement (k = 0.93). Surface coil signal reception rendered a high SNR (mean 151.28 ± 54.04) and CNR (mean 120.75 ± 46.47). Despite lower SNR and CNR of the cranial and cervical vessels, a two-step injection protocol exhibited less venous superposition and therefore proved to be superior compared to single-bolus injection. Conclusion Our approach provides accurate noninvasive high-resolution imaging of systemic atherosclerotic disease, covering the arterial vasculature from intracranial arteries to distal runoff vessels. The recently introduced MR scanner and coil technology is feasible to significantly increase the performance of whole-body MRA. J. Magn. Reson. Imaging 2005;21:596,603. © 2005 Wiley-Liss, Inc. [source] Topographic Patterns of Small Subcortical Infarcts Associated with MCA Stenosis: A Diffusion-Weighted MRI StudyJOURNAL OF NEUROIMAGING, Issue 3 2006Xin Wang MD ABSTRACT Background and Purpose. Small subcortical infarcts (SSI, maximum lesion diameter ,2.0 cm) are usually considered as infarcts caused by small vessel disease. However, SSI can also be associated with large artery occlusive disease such as middle cerebral artery (MCA) stenosis. We performed a prospective study to investigate the relationship between MCA stenosis and SSI distribution and further to investigate the mechanism of SSI caused by MCA stenosis. Methods. Magnetic resonance angiography (MRA) and diffusion-weighed MRI (DWI) of consecutive acute ischemic stroke patients with recent SSI were studied. The distribution of acute infarcts on DWI was categorized as cortical infarct (CI), border zone infarct (BI), or perforating artery infarct (PAI). Results. Totally, 93 cases were recruited, among which 12 had single SSI with MCA stenosis (group 1) and 26 patients had multiple SSI with MCA stenosis (group 2), while 55 patients without MCA stenosis had single SSI (group 3). For patients with single SSI and MCA stenosis, 6 had BI and 6 had PAI; for patients with multiple SSI and MCA stenosis, 25 had BI, 4 had PAI and 9 had CI (compared with group1: P= .001); for patients with single SSI but without MCA stenosis, 20 had BI and 35 had PAI (compared with group1: P= .58). Conclusion. Multiple acute infarcts along the border zone are the commonest pattern in small infarcts with MCA stenosis, especially among those with multiple acute infarcts. Our data suggest that hemodynamic compromise and artery-to-artery embolism may be both important factors for infarcts in patients with MCA stenosis. [source] Time Development Models for Perfusion Provocations Studied with Laser-Doppler Flowmetry, Applied to Iontophoresis and PORHMICROCIRCULATION, Issue 7 2009Frits F.M. De Mul ABSTRACT Objective: Clinical acceptance of laser-Doppler perfusion monitoring (LDPM) of microcirculation suffers from lack of quantitatively reliable signal data, due to varying tissue constitution, temperature, hydration, etc. In this article, we show that a novel approach using physiological models for response upon provocations provides quantitatively and clinically relevant time constants. Methods: We investigated this for two provocation protocols: postocclusive reactive hyperemia (PORH) and iontophoresis shots, measured with LDPM on extremities. PORH experiments were performed on patients with peripheral arterial occlusive disease (PAOD) or diabetes mellitus (DM), and on healthy controls. Iontophoresis experiments were performed on pre-eclamptic patients and healthy controls. We developed two dynamical physical models, both based on two characteristic time constants: for PORH, an "arterial" and a "capillary" time constant and, for iontophoresis, a "diffusion" and a "decay" time constant. Results: For the different subject groups, we could extract time constants that could probably be related to physiological differences. For iontophoresis, a shot saturation constant was determined, with very different values for different groups and administered drugs. Conclusions: With these models, the dynamics of the provocations can be investigated and quantitative comparisons between experiments and subject groups become available. The models offer a quantifiable standard that is independent of the type of LDPM instrumentation. [source] Intracranial hemorrhage following allogeneic hematopoietic stem cell transplantation,AMERICAN JOURNAL OF HEMATOLOGY, Issue 5 2009Yuho Najima Charts and radiographs of 622 allogeneic hematopoietic stem cell transplant (HSCT) recipients, over a 20-year period, were retrospectively reviewed for intracranial hemorrhage (ICH) following transplant. A total of 21 cases of ICH were identified (3.4%) including 15 cases of intraparenchymal hemorrhage (IPH), two cases of subarachnoid hemorrhage (SAH), and four cases of subdural hematoma (SDH). The median time from transplantation to the onset of ICH was 63 days (range, 6,3,488 days). The clinical features of post-transplant ICH patients were similar and included hypertension, diabetes mellitus, chronic graft-versus-host disease (GVHD), systemic infection, and veno occlusive disease (VOD), recently referred to as sinusoidal obstruction syndrome, in addition to severe thrombocytopenia. Mortality rate was especially high (89%) after IPH with a median survival of 2 days (range, 0,148 days). In contrast, all patients with SAH or SDH following HSCT survived. The cause of post-transplant ICH appears to be multifactorial, including thrombocytopenia, hypertension, acute GVHD, VOD, and radiation therapy. Most patients in our series displayed severe thrombocytopenia at the onset of ICH, even though adequate prophylactic platelet transfusions were given. By univariate analysis, cord blood transplantation, acute GVHD, systemic infection, and VOD were related to the incidence of ICH, whereas prior CNS episodes and radiation therapy did not reach statistical significance. A multivariate analysis with logistic regression identified acute GVHD as the only factor that significantly influenced ICH occurrence. Am. J. Hematol. 2009. © 2009 Wiley-Liss, Inc. [source] Pediatric moyamoya disease: An analysis of 410 consecutive casesANNALS OF NEUROLOGY, Issue 1 2010Seung-Ki Kim MD Objective Moyamoya disease (MMD) is a cerebrovascular occlusive disease of the bilateral internal carotid arteries that causes a compensatory abnormal vascular network at the base of brain. The rare incidence and various surgical techniques applied have limited the clinical research on MMD. Methods We conducted a retrospective analysis of the surgical outcome of 410 pediatric MMD patients. All patients were treated in a relatively uniform scheme at a single institution. The surgical procedures consisted of bilateral encephaloduroarteriosynangiosis augmented by bifrontal encephalogaleo-/periosteal synangiosis. Logistic regression analyses were applied to reveal the prognostic factors for surgical outcome. Results The overall clinical outcome was excellent in 66%, good in 15%, fair in 15%, and poor in 4% of the patients. Therefore, 81% of the patients had a favorable clinical outcome (excellent and good). Multivariate analyses revealed that infarction on presentation was associated with unfavorable clinical outcome (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.49,5.46; p < 0.01) and decreased vascular reserve only on single-photon emission computerized tomography (OR, 0.07; 95% CI, 0.01,0.52; p < 0.01), with favorable clinical outcome. Interpretation Our results indicate that an early diagnosis and active intervention before establishment of irreversible hemodynamic change are essential to achieve a favorable clinical outcome in children with MMD. ANN NEUROL 2010;68:92,101 [source] New England medical center posterior circulation registryANNALS OF NEUROLOGY, Issue 3 2004Louis R. Caplan MD Among 407 New England Medical Center Posterior Circulation registry patients, 59% had strokes without transient ischemic attacks (TIAs), 24% had TIAs then strokes, and 16% had only TIAs. Embolism was the commonest stroke mechanism (40% of patients including 24% cardiac origin, 14% intraarterial, 2% cardiac and arterial sources). In 32% large artery occlusive lesions caused hemodynamic brain ischemia. Infarcts most often included the distal posterior circulation territory (rostral brainstem, superior cerebellum and occipital and temporal lobes); the proximal (medulla and posterior inferior cerebellum) and middle (pons and anterior inferior cerebellum) territories were equally involved. Severe occlusive lesions (>50% stenosis) involved more than one large artery in 148 patients; 134 had one artery site involved unilaterally or bilaterally. The commonest occlusive sites were: extracranial vertebral artery (52 patients, 15 bilateral) intracranial vertebral artery (40 patients, 12 bilateral), basilar artery (46 patients). Intraarterial embolism was the commonest mechanism of brain infarction in patients with vertebral artery occlusive disease. Thirty-day mortality was 3.6%. Embolic mechanism, distal territory location, and basilar artery occlusive disease carried the poorest prognosis. The best outcome was in patients who had multiple arterial occlusive sites; they had position-sensitive TIAs during months to years. Ann Neurol 2004;56:389,398 [source] THE CONUNDRUM OF CLAUDICATIONANZ JOURNAL OF SURGERY, Issue 10 2006Ramon L. Varcoe Stable claudication has traditionally been treated conservatively by many clinicians as operative therapies involve considerable risk for a condition that is often slowly progressive and non-fatal. The relative safety of less invasive endovascular techniques brings potential survival benefits from the increased exercise tolerance that result. We aimed to revisit and clarify the aetiologies of intermittent claudication in a review of the rarer causes that can mimic atherosclerotic occlusive disease. An extensive search of Medline, Embase and the Cochrane databases was carried out to compile published work addressing the aetiology of claudication and specific non-atherosclerotic causes. The reference lists of these manuscripts were also searched for relevant articles. There are several vasculogenic and neurogenic causes for intermittent claudication, many of which are unrelated to atherosclerosis. Recognition of these rarer syndromes is essential when planning endovascular or operative management strategies. Consideration of non-atherosclerotic differential diagnoses is recommended when assessing the patient with intermittent claudication. This is particularly critical in the young patient whose pattern of symptoms and risk factors may not fit precisely with atherosclerosis. [source] Retinal and Optic Nerve DiseasesARTIFICIAL ORGANS, Issue 11 2003Eyal Margalit Abstract:, A variety of disease processes can affect the retina and/or the optic nerve, including vascular or ischemic disease, inflammatory or infectious disease, and degenerative disease. These disease processes may selectively damage certain parts of the retina or optic nerve, and the specific areas that are damaged may have implications for the design of potential therapeutic visual prosthetic devices. Outer retinal diseases include age-related macular degeneration, pathologic myopia, and retinitis pigmentosa. Although the retinal photoreceptors may be lost, the inner retina is relatively well-preserved in these diseases and may be a target for retinal prosthetic devices. Inner retinal diseases include retinal vascular diseases such as diabetic retinopathy, retinal venous occlusive disease, and retinopathy of prematurity. Other retinal diseases such as ocular infections (retinitis, endophthalmitis) may affect all retinal layers. Because the inner retinal cells, including the retinal ganglion cells, may be destroyed in these diseases (inner retinal or whole retinal), prosthetic devices that stimulate the inner retina may not be effective. Common optic nerve diseases include glaucoma, optic neuritis, and ischemic optic neuropathy. Because the ganglion cell nerve fibers themselves are damaged, visual prosthetics for these diseases will need to target more distal portions of the visual pathway, such as the visual cortex. Clearly, a sound understanding of retinal and optic nerve disease pathophysiology is critical for designing and choosing the optimal visual prosthetic device. [source] Mid-term outcome of endovascular revascularization for chronic mesenteric ischaemia,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 2 2010N. V. Dias Background: This study aimed to assess mid-term outcome after endovascular revascularization of chronic occlusive mesenteric ischaemia (CMI) and to identify possible predictors of mortality. Methods: Consecutive patients undergoing primary elective stenting for CMI between 1995 and 2007 were registered prospectively in a database. Patients with acute ischaemia were excluded. Retrospective case-note review and data analysis were performed. Results: Forty-three patients (10 men) were treated for stable (n = 30) or exacerbated (n = 13) CMI. Their median (interquartile range (i.q.r.)) age was 70 (60,79) years. Revascularization was successful in 47 of 49 vessels. The superior mesenteric artery (SMA), either alone (n = 34) or in combination with the coeliac trunk (n = 6), was the predominant target vessel. No patient died within 30 days. Median follow-up was 43 (i.q.r. 25,63) months and the estimated (s.e.) 3-year overall survival rate was 76(7) per cent. Two patients died from distal SMA occlusive disease and intestinal infarction after 6 and 18 months respectively. Previous stroke (P = 0·016), male sex (P = 0·057) and age (P = 0·066) were associated with mid-term mortality on univariable, but not multivariable analysis. Reintervention was needed in 14 patients, achieving a 3-year cumulative rate of freedom from recurrent symptoms of 88(5) per cent. Conclusion: Endovascular treatment provided high early and mid-term survival rates in this series of patients with CMI, with low complication rates. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Association between plaque instability, angiogenesis and symptomatic carotid occlusive disease,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2001R. Mofidi Background: Angiogenesis is a recognized feature of the atherosclerotic process and has been described in the context of unstable coronary atherosclerotic lesions. The aim of this study was to assess the association between angiogenesis in atherosclerotic carotid plaques and microscopic features of plaque instability, in particular intraplaque haemorrhage. Methods: Consecutive patients undergoing carotid endarterectomy were included. Endarterectomy specimens were divided into their constituent atherosclerotic lesions. Histological sections were prepared and stained with haematoxylin and eosin, and immunohistochemically with an endothelial cell marker (CD34). The quantity of intraplaque haemorrhage was measured in transverse histological sections using computerized image analysis. Microvessel counts were performed in CD34-stained sections and were verified through computerized image analysis. Results: Some 239 atherosclerotic lesions from 73 patients were available for analysis; 73 were early lesions, 74 were raised fibroatheromas and 92 were unstable atherosclerotic plaques. One hundred and fifty lesions were not haemorrhagic; 89 exhibited intraplaque haemorrhage, of which 28 involved less than 50 per cent of the plaque sectional area. There were higher microvessel counts in plaques containing over 50 per cent haemorrhage (P < 0·0001), unstable atherosclerotic lesions (P < 0·0001) and atherosclerotic lesions obtained from symptomatic patients (P < 0·001). Conclusion: There are strong associations between plaque vascularity, quantity of intraplaque haemorrhage and presence of symptomatic carotid occlusive disease. © 2001 British Journal of Surgery Society Ltd [source] Preliminary study of D-dimer as a possible marker of acute bowel ischaemiaBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 3 2001Dr S. Acosta Background: Occlusion of the superior mesenteric artery (SMA) demands prompt recognition and diagnosis. No accurate diagnostic method is available. The aim of this study was to determine whether the fibrinolytic marker D-dimer is a useful early marker of acute bowel ischaemia. Methods: Fourteen patients suspected of having acute bowel ischaemia were analysed for an increase in plasma D-dimer level. Results: Six patients had embolic or thrombotic occlusion of the SMA and all had significantly higher D-dimer levels than those without thromboembolic occlusion (P < 0·05). Four patients with strangulation of the small bowel due to adhesions and one with a ruptured aortic aneurysm also had raised D-dimer values. Conclusion: In patients with suspected thromboembolic occlusive disease of the SMA, a raised level of D-dimer indicated the presence of acute bowel ischaemia, whatever the cause. A more extensive prospective study is needed to evaluate a potential survival benefit using the test as a marker of the need for urgent laparotomy. © 2001 British Journal of Surgery Society Ltd [source] Combined glycoprotein IIb/IIIa receptor inhibition and low-dose fibrinolysis for peripheral arterial thrombosisCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2002Krishna J. Rocha-Singh MD Abstract This feasibility study evaluated the therapeutic potential of combined GP IIb/IIIa receptor inhibition with abciximab and low-dose fibrinolysis with reteplase for treatment of acute femoropopliteal thrombosis. The simultaneous intra-arterial administration of abciximab in conjunction with low-dose reteplase (, 0.5 U/hr) was safe in 13 patients; 2 patients experienced major hemorrhagic complication at a reteplase dose of 1 U/hr. The primary success rate was 100%; all patients experienced an excellent clinical response with no clinical evidence of distal embolization. No patient required repeat endovascular or surgical revascularization during mean follow-up of 9.3 months. This promising new thrombolytic strategy for the treatment of peripheral arterial occlusive disease requires further study. Cathet Cardiovasc Intervent 2002;55:457,460. © 2002 Wiley-Liss, Inc. [source] Ultrasound contrast enhancing agents in neurosonology: principles, methods,future possibilitiesACTA NEUROLOGICA SCANDINAVICA, Issue 1 2000D. W. Droste Objectives, Ultrasound of the brain supplying arteries is a standard diagnostic procedure in patients with suspected and definite acute and chronic cerebrovascular occlusive disease. Anatomical and pathological limitations led to the development of echocontrast agents which are able to survive pulmonary and capillary transit and improve the echogenicity of the flowing blood. Material and Methods, This article reviews present and future applications of echocontrast agents in conjunction with personal experiences. Results, Currently, echocontrast is used for the differentiation of internal carotid artery occlusion and pseudoocclusion, better delineation of the maximal narrowing in high-grade stenoses, and better visualization of the extracranial vertebral artery and its collaterals. Transcranial applications include the insufficient foraminal or temporal window, assessment of arteriovenous malformations, thrombosis of cerebral veins and sinuses, and intracranial aneurysms. The use of echocontrast can have direct diagnostic and therapeutic consequences. Harmonic imaging, perfusion imaging, stimulated acoustic emission, and drug delivery are possible future domains of the technique. Discussion, Besides the support of conventional neurovascular ultrasound in poor examination conditions due to the patients' anatomy or pathology, echocontrast agents may allow for novel applications in the diagnosis and treatment of cerebrovascular patients. [source] Factor XI deficiency in animal modelsJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009T. RENNÉ Summary., The blood coagulation system forms fibrin to limit blood loss from sites of injury, but also contributes to occlusive diseases such as deep vein thrombosis, myocardial infarction, and stroke. In the current model of a coagulation balance, normal hemostasis and thrombosis represent two sides of the same coin; however, data from coagulation factor XI-deficient animal models have challenged this dogma. Gene targeting of factor XI, a serine protease of the intrinsic pathway of coagulation, severely impairs arterial thrombus formation but is not associated with excessive bleeding. Mechanistically, factor XI may be activated by factor XII following contact activation or by thrombin in a feedback activation loop. This review focuses on the role of factor XI, and its deficiency states as novel target for prevention of thrombosis with low bleeding risk in animal models. 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