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1.
Rev Neurol (Paris) ; 178(3): 219-225, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34785042

ABSTRACT

OBJECTIVES: To estimate the intra -and inter-rater consistency of radiologist and neurologist working in pairs attributing DWI-ASPECTS (Diffusion Alberta Stroke Program Early CT Score) in patients with acute middle cerebral artery ischemic stroke referred for mechanical thrombectomy, intravenous thrombolysis or bridging therapy. METHODS: Five neurologists and 5 radiologists working in pairs and in hour period scored independently and in two reading sessions anonymized DWI-ASPECTS of 80 patients presenting with acute anterior ischaemic stroke in our center. We measured agreement between pairs using intraclass correlation coefficients (ICCs). A Fleiss kappa was used for dichotomized (0-6;7-10) and trichotomized (0-3;4-6;7-10) ASPECTS. The interrater distribution of the score in the trichotomized (0-3;4-6;7-10) ASPECTS was calculated. We determined the interrater (Cohen kappa) and intrarater (Fleiss kappa) agreement on the ASPECTS regions. RESULTS: The average DWI-ASPECTS was 6.35 (SD±2.44) for the first reading, and 6.47 (SD±2.44) for the second one. The ICC was 0.853 (95%CI, 0.798-0.896) for the interrater, and 0.862 (95%CI, 0.834-0.885) for the intrarater evaluation. Kappa coefficients were high for dichotomized (k=0.75) and trichotomized (k=0.64) ASPECTS. Evaluators agreement on the ASPECTS category (0-3), (4-6) and (7-10) was 88, 76 and 93% respectively. The anatomic region infarcted was well identified (k=0.70-0.77), except for the internal capsula (k=0.57). Interrater agreement was fair for M5 (k=0.37), moderate for internal capsula (0.52) and substantial for the other regions (0.60-0.79). CONCLUSIONS: Reliability of DWI-ASPECTS is good when determined by radiologist and neurologist working in pairs, which corresponds to our current clinical practice. However, discrepancies are possible for cut-off determination, which may impact the indication of thrombectomy, and for the determination of the exact infarcted region. Agreement to propose category (4-6) is lower than for (0-3) and (8-10) ASPECTS categories.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Brain Ischemia/diagnostic imaging , Brain Ischemia/therapy , Humans , Neurologists , Radiologists , Reproducibility of Results , Stroke/diagnostic imaging , Stroke/therapy
2.
J Mol Cell Cardiol ; 155: 36-49, 2021 06.
Article in English | MEDLINE | ID: mdl-33652022

ABSTRACT

RATIONALE: Thioredoxin-interacting protein (Txnip) is a novel molecular target with translational potential in diverse human diseases. Txnip has several established cellular actions including binding to thioredoxin, a scavenger of reactive oxygen species (ROS). It has been long recognized from in vitro evidence that Txnip forms a disulfide bridge through cysteine 247 (C247) with reduced thioredoxin to inhibit the anti-oxidative properties of thioredoxin. However, the physiological significance of the Txnip-thioredoxin interaction remains largely undefined in vivo. OBJECTIVE: A single mutation of Txnip, C247S, abolishes the binding of Txnip with thioredoxin. Using a conditional and inducible approach with a mouse model of a mutant Txnip that does not bind thioredoxin, we tested whether the interaction of thioredoxin with Txnip is required for Txnip's pro-oxidative or cytotoxic effects in the heart. METHODS AND RESULTS: Overexpression of Txnip C247S in cells resulted in a reduction in ROS, due to an inability to inhibit thioredoxin. Hypoxia (1% O2, 24 h)-induced killing effects of Txnip were decreased by lower levels of cellular ROS in Txnip C247S-expressing cells compared with wild-type Txnip-expressing cells. Then, myocardial ischemic injuries were assessed in the animal model. Cardiomyocyte-specific Txnip C247S knock-in mice had better survival with smaller infarct size following myocardial infarction (MI) compared to control animals. The absence of Txnip's inhibition of thioredoxin promoted mitochondrial anti-oxidative capacities in cardiomyocytes, thereby protecting the heart from oxidative damage induced by MI. Furthermore, an unbiased RNA sequencing screen identified that hypoxia-inducible factor 1 signaling pathway was involved in Txnip C247S-mediated cardioprotective mechanisms. CONCLUSION: Txnip is a cysteine-containing redox protein that robustly regulates the thioredoxin system via a disulfide bond-switching mechanism in adult cardiomyocytes. Our results provide the direct in vivo evidence that regulation of redox state by Txnip is a crucial component for myocardial homeostasis under ischemic stress.


Subject(s)
Alleles , Amino Acid Substitution , Carrier Proteins/genetics , Disease Resistance/genetics , Mutation , Myocardial Infarction/etiology , Thioredoxins/genetics , Adenosine Triphosphate/metabolism , Animals , Biomarkers , Carrier Proteins/metabolism , Cell Line , Disease Models, Animal , Disease Susceptibility , Electrocardiography , Gene Expression , Glucose/metabolism , Hypoxia/genetics , Hypoxia/metabolism , Hypoxia-Inducible Factor 1/metabolism , Mice , Mice, Transgenic , Myocardial Infarction/diagnosis , Myocardial Infarction/metabolism , Organ Specificity/genetics , Oxidation-Reduction , Oxidative Stress , Reactive Oxygen Species/metabolism , Thioredoxins/metabolism , Ubiquitin Thiolesterase/metabolism
3.
Clin Nucl Med ; 46(2): e84-e85, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33031242

ABSTRACT

ABSTRACT: Gallbladder perforation is an uncommon but morbid complication of acute cholecystitis with mural ischemia and necrosis. The most common site of perforation is the fundus because of limited blood supply in this region. The Niemeier classification proposed in 1934 remains the criterion standard in grading gallbladder perforation; type 1 is acute with free perforation into the peritoneal cavity, type 2 is subacute with pericholecystic abscess, and type 3 is chronic with cholecystoenteric fistula. We report a challenging case of type 1 gallbladder perforation due to acute acalculous cholecystitis.


Subject(s)
Gallbladder/pathology , Peritoneal Cavity/pathology , Cholecystitis, Acute/etiology , Gallbladder Diseases/complications , Humans , Intestinal Fistula/etiology , Male
6.
Rev Neurol (Paris) ; 173(4): 216-221, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28377089

ABSTRACT

BACKGROUND: Since 2015, the emergence of mechanical thrombectomy as standard care in acute stroke has involved organizational changes not only for stroke centers, but also for entire emergency regional networks. The aim of our study was to assess the proportion of ischemic stroke patients, admitted to stroke units in the Northern French Alps within the first 6h of onset, eligible for thrombectomy. METHODS: This study retrospectively analyzed the clinical and radiological data of all acute stroke patients hospitalized at three stroke units of the Northern French Alps Emergency Network (RENAU) in 2014. Eligible patients had proximal arterial occlusions of the anterior and posterior cerebral circulation, as confirmed by brain imaging, which could be treated by thrombectomy within 6h of symptom onset. RESULTS: Of the 435 cases of acute ischemic stroke, 152 patients were treated by intravenous thrombolysis (IV rtPA). Of these patients, 83 (55%) had intracranial occlusions and were eligible for combined thrombectomy. Of the 283 patients not treatable by IV rtPA, 32 patients (11%) were eligible for primary thrombectomy. CONCLUSION: Thrombectomy could be performed in 26% of our acute ischemic stroke patients (n=115/435), and a large increase in endovascular procedures is expected over the next few years that will require close collaboration among all partners in the emergency networks. Using our RENAU stroke database, it will be possible to compare various factors contributing to effective activity.


Subject(s)
Stroke/surgery , Thrombectomy/statistics & numerical data , Aged , Brain Ischemia/drug therapy , Cerebrovascular Circulation , Databases, Factual , Eligibility Determination , Female , Fibrinolytic Agents/administration & dosage , Fibrinolytic Agents/therapeutic use , France/epidemiology , Humans , Magnetic Resonance Angiography , Male , Middle Aged , Registries , Retrospective Studies , Stroke/drug therapy , Stroke/epidemiology , Thrombolytic Therapy , Time-to-Treatment , Treatment Outcome
7.
PLoS One ; 12(3): e0173823, 2017.
Article in English | MEDLINE | ID: mdl-28291835

ABSTRACT

Adaptive thermogenesis and cold-induced activation of uncoupling protein 1 (Ucp1) in brown adipose tissue in rodents is well-described and attributed to sympathetic activation of ß-adrenergic signaling. The arrestin domain containing protein Arrdc3 is a regulator of obesity in mice and also appears linked to obesity in humans. We generated a mouse with conditional deletion of Arrdc3, and here we present evidence that genetic ablation of Arrdc3 specifically in adipocytes results in increased Ucp1 expression in subcutaneous and parametrial adipose tissue. Although this increase in expression did not correspond with significant changes in body weight or energy expenditure, adipocyte-specific Arrdc3-null mice had improved glucose tolerance. It was previously hypothesized that Arrdc3 ablation leads to increased ß-adrenergic receptor sensitivity; however, in vitro experiments show that Arrdc3-null adipocytes responded to ß-adrenergic receptor agonist with decreased Ucp1 levels. Additionally, canonical ß-adrenergic receptor signaling was not different in Arrdc3-null adipocytes. These data reveal a role for Arrdc3 in the regulation of Ucp1 expression in adipocytes. However, this adipocyte effect is insufficient to generate the obesity-resistant phenotype of mice with ubiquitous deletion of Arrdc3, indicating a likely role for Arrdc3 in cells other than adipocytes.


Subject(s)
Adipose Tissue, White/metabolism , Arrestins/physiology , Receptors, Adrenergic, beta/metabolism , Signal Transduction , Uncoupling Protein 1/metabolism , Animals , Arrestins/genetics , Body Composition , Mice , Mice, Knockout
8.
J Cardiovasc Pharmacol Ther ; 22(3): 219-229, 2017 05.
Article in English | MEDLINE | ID: mdl-27807222

ABSTRACT

Myocardial ischemia/reperfusion injury represents a major threat to human health and contributes to adverse cardiovascular outcomes worldwide. Despite the identification of numerous molecular mechanisms, understanding of the complex pathophysiology of this clinical syndrome remains incomplete. Thioredoxin-interacting protein (Txnip) has been of great interest in the past decade since it has been reported to be a critical regulator in human diseases with several important cellular functions. Thioredoxin-interacting protein binds to and inhibits thioredoxin, a redox protein that neutralizes reactive oxygen species (ROS), and through its interaction with thioredoxin, Txnip sensitizes cardiomyocytes to ROS-induced apoptosis. Interestingly, evidence from recent studies also suggests that some of the effects of Txnip may be unrelated to changes in thioredoxin activity. These pleiotropic effects of Txnip are mediated by interactions with other signaling molecules, such as nod-like receptor pyrin domain-containing 3 inflammasome and glucose transporter 1. Indeed, Txnip has been implicated in the regulation of inflammatory response and glucose homeostasis during myocardial ischemia/reperfusion injury. This review attempts to make the case that in addition to interacting with thioredoxin, Txnip contributes to some of the pathological consequences of myocardial ischemia and infarction through endogenous signals in multiple molecular mechanisms.


Subject(s)
Carrier Proteins/metabolism , Myocardial Reperfusion Injury/metabolism , Myocardium/metabolism , Oxidative Stress , Animals , Apoptosis , Glucose/metabolism , Humans , Inflammation Mediators/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Myocardial Reperfusion Injury/genetics , Myocardial Reperfusion Injury/pathology , Myocardium/pathology , Reactive Oxygen Species/metabolism , Signal Transduction
9.
Am J Physiol Heart Circ Physiol ; 310(11): H1748-59, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27037370

ABSTRACT

Although the precise pathogenesis of diabetic cardiac damage remains unclear, potential mechanisms include increased oxidative stress, autonomic nervous dysfunction, and altered cardiac metabolism. Thioredoxin-interacting protein (Txnip) was initially identified as an inhibitor of the antioxidant thioredoxin but is now recognized as a member of the arrestin superfamily of adaptor proteins that classically regulate G protein-coupled receptor signaling. Here we show that Txnip plays a key role in diabetic cardiomyopathy. High glucose levels induced Txnip expression in rat cardiomyocytes in vitro and in the myocardium of streptozotocin-induced diabetic mice in vivo. While hyperglycemia did not induce cardiac dysfunction at baseline, ß-adrenergic challenge revealed a blunted myocardial inotropic response in diabetic animals (24-wk-old male and female C57BL/6;129Sv mice). Interestingly, diabetic mice with cardiomyocyte-specific deletion of Txnip retained a greater cardiac response to ß-adrenergic stimulation than wild-type mice. This benefit in Txnip-knockout hearts was not related to the level of thioredoxin activity or oxidative stress. Unlike the ß-arrestins, Txnip did not interact with ß-adrenergic receptors to desensitize downstream signaling. However, our proteomic and functional analyses demonstrated that Txnip inhibits glucose transport through direct binding to glucose transporter 1 (GLUT1). An ex vivo analysis of perfused hearts further demonstrated that the enhanced functional reserve afforded by deletion of Txnip was associated with myocardial glucose utilization during ß-adrenergic stimulation. These data provide novel evidence that hyperglycemia-induced Txnip is responsible for impaired cardiac inotropic reserve by direct regulation of insulin-independent glucose uptake through GLUT1 and plays a role in the development of diabetic cardiomyopathy.


Subject(s)
Carrier Proteins/metabolism , Diabetes Mellitus, Experimental/metabolism , Glucose Transporter Type 1/metabolism , Myocardial Contraction/genetics , Myocardium/metabolism , Thioredoxins/metabolism , Animals , Carrier Proteins/genetics , Cell Line , Diabetes Mellitus, Experimental/genetics , Female , Glucose/pharmacology , Humans , Male , Mice , Mice, Knockout , Myocardial Contraction/drug effects , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Rats , Receptors, Adrenergic, beta/metabolism , Thioredoxins/genetics
10.
AJNR Am J Neuroradiol ; 37(5): 879-84, 2016 May.
Article in English | MEDLINE | ID: mdl-26659336

ABSTRACT

BACKGROUND AND PURPOSE: Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA. MATERIALS AND METHODS: A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey. RESULTS: The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial.


Subject(s)
Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Magnetic Resonance Angiography/methods , Neuroimaging/methods , Angiography, Digital Subtraction/methods , Embolization, Therapeutic/methods , Female , Humans , Male , Middle Aged , Multimodal Imaging/methods , Reproducibility of Results , Treatment Outcome
11.
Interv Neuroradiol ; 19(1): 83-6, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23472729

ABSTRACT

This paper reports the cost of endovascular materials used for the treatment of large-vessel ischemic stroke in the anterior circulation according to the angiographic score and clinical results at three months. From November 2009 to July 2011, 57 ischemic patients (mean age, 64.6 ±13.8 years) with anterior large vessel occlusion were included. Mean National Institutes of Health Stroke Scale (NIHSS) on admission was 18.4 ± 4.9. Mean duration of symptoms until the arterial puncture was 207±67 minutes. Recanalization was assessed using the Thrombolysis In Myocardial Infarction (TIMI) score. Patient selection was performed on a non-enhanced CT scanner. According to the TIMI final angiographic score and the modified Rankin score (mRS) at three months, we determined the cost of the material used. Complete (n=12, TIMI grade 3) or partial perfusion (n=35, TIMI grade 2) was achieved in 47 (82.5%) lesions. At three months, 33.3% (n=19) had a mRS score ≤ 2. The mean cost of the material used in the operative room was 5018±2402 euro. Intra-arterial thrombolysis presents a substantial initial cost and the long-term economic impact has to be evaluated. Our health system has to take the price of these new technologies into account for future medical choices and urgently evaluate them in randomized controlled trials.


Subject(s)
Anterior Cerebral Artery/surgery , Infarction, Anterior Cerebral Artery/economics , Infarction, Anterior Cerebral Artery/surgery , Thrombectomy/economics , Thrombectomy/instrumentation , Aged , Anterior Cerebral Artery/diagnostic imaging , Brain Ischemia/diagnostic imaging , Brain Ischemia/economics , Brain Ischemia/surgery , Cerebral Angiography , Cost-Benefit Analysis , Female , Health Expenditures , Hospital Costs , Humans , Infarction, Anterior Cerebral Artery/diagnostic imaging , Male , Middle Aged
12.
Acta Virol ; 57(1): 85-6, 2013.
Article in English | MEDLINE | ID: mdl-23530829

ABSTRACT

We have previously examined the antiviral effects of total alkaloids from Commelina communis L. (TAC). Here we investigated the active constituents of TAC, responsible for the antiviral effect. Harman, homonojirimycin (HNJ) and 2,5-dihydroxymethyl-3,4-dihydroxypyrrolidine were isolated from TAC by HPLC. Only HNJ showed strong antiviral activity against influenza A/PR/8/34 virus (H1N1) as measured by cytopathic effect reduction assay. The results suggest that HNJ is one of the active components of TAC.


Subject(s)
1-Deoxynojirimycin/analogs & derivatives , Antiviral Agents/pharmacology , Commelina/chemistry , Influenza A Virus, H1N1 Subtype/drug effects , 1-Deoxynojirimycin/isolation & purification , 1-Deoxynojirimycin/pharmacology , Alkaloids/pharmacology , Animals , Chromatography, High Pressure Liquid , Dogs , Harmine/analogs & derivatives , Harmine/pharmacology , Imino Furanoses/pharmacology , Madin Darby Canine Kidney Cells , Mannitol/analogs & derivatives , Mannitol/pharmacology
13.
AJNR Am J Neuroradiol ; 34(3): 570-6, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22899786

ABSTRACT

BACKGROUND AND PURPOSE: Endovascular treatment of wide-neck bifurcation aneurysms often results in incomplete occlusion or aneurysm recurrence. The goals of this study were to compare results of coil embolization with or without the assistance of self-expandable stents and to examine how stents may influence neointima formation. MATERIALS AND METHODS: Wide-neck bifurcation aneurysms were constructed in 24 animals and, after 4-6 weeks, were randomly allocated to 1 of 5 groups: 1) coil embolization using the assistance of 1 braided stent (n = 5); 2) coil embolization using the assistance of 2 braided stents in a Y configuration (n = 5); 3) coil embolization without stent assistance (n = 6); 4) Y-stenting alone (n = 4); and 5) untreated controls (n = 4). Angiographic results were compared at baseline and at 12 weeks, by using an ordinal scale. Neointima formation at the neck at 12 weeks was compared among groups by using a semiquantitative grading scale. Bench studies were performed to assess stent porosities. RESULTS: Initial angiographic results were improved with single stent-assisted coiling compared with simple coiling (P = .013). Angiographic results at 12 weeks were improved with any stent assistance (P = .014). Neointimal closure of the aneurysm neck was similar with or without stent assistance (P = .908), with neointima covering coil loops but rarely stent struts. Y-stent placement alone had no therapeutic effect. Bench studies showed that porosities can be decreased with stent compaction, but a relatively stable porous transition zone was a limiting factor. CONCLUSIONS: Stent-assisted coiling may improve results of embolization by allowing more complete initial coiling, but these high-porosity stents did not provide a scaffold for more complete neointimal closure of aneurysms.


Subject(s)
Blood Vessel Prosthesis , Endovascular Procedures/instrumentation , Intracranial Aneurysm/surgery , Mechanical Thrombolysis/instrumentation , Stents , Animals , Combined Modality Therapy/instrumentation , Dogs , Endovascular Procedures/methods , Equipment Design , Equipment Failure Analysis , Intracranial Aneurysm/diagnostic imaging , Radiography , Treatment Outcome
14.
AJNR Am J Neuroradiol ; 34(3): 596-602, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22878007

ABSTRACT

BACKGROUND AND PURPOSE: Braided self-expandable stents and flow diverters of uniform construction may develop zones of heterogeneous porosity in vivo. Unwanted stenoses may also occur at the extremities of the device. We studied these phenomena in dedicated benchtop experiments. MATERIALS AND METHODS: Five braided devices of decreasing porosity were studied. To simulate discrepancies in diameters between the landing zones of the parent vessel and the aneurysm neck area, device extremities were inserted into silicone tubes of various diameters (2-3 mm), leaving the midportion free to react to experimental manipulations, which included axial approximation of the tubes (0-7 mm), and curvature (0-135°), with or without axial compression (0-2 mm). The length of the landing zone was sequentially decreased to study terminal device stenosis. RESULTS: All devices adopted a conformation characterized by 3 different zones: bilateral landing zones, a middle compaction zone, and 2 transition zones. It is possible, during deployment, to compact stents and FDs to decrease porosity, but a limiting factor was the transition zone, which remained relatively unchanged and of higher porosity than the expansion zone. Length of the transition zone increased when devices were constrained in smaller tubes. Heterogeneities in porosity with compaction and curvatures were predictable and followed simple geometric rules. Extremity stenoses occurred increasingly with decreasing length of the landing zone. CONCLUSIONS: Braided self-expandable devices show predictable changes in porosity according to device size, vessel diameter, and curvature. Adequate landing zones are required to prevent terminal device stenosis.


Subject(s)
Blood Vessel Prosthesis , Prosthesis Failure , Stents , Equipment Design , Equipment Failure Analysis , Porosity
15.
AJNR Am J Neuroradiol ; 33(10): 2004-9, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22555582

ABSTRACT

BACKGROUND AND PURPOSE: FDs are new intracranial stents designed to occlude aneurysms while preserving flow to jailed arterial branches. We tested this fundamental principle in a new aneurysm model. MATERIALS AND METHODS: Canine lateral wall aneurysms, featuring a branch located immediately opposite the aneurysm, were created in 16 animals to study the effects on aneurysm or branch occlusion using single HP stents (n = 4), 2 overlapping HP stents (n = 4), or an FD (n = 8). Two other animals, in which an efferent arterial branch was anastomosed to the aneurysm fundus, were also treated with FDs. Angiographic results after deployment, at 2 weeks, and at 3 months were scored using an ordinal scale. The metal porosity of the FSS and the amount of FSS neointima formation was determined by postmortem photography. RESULTS: FDs led to better angiographic occlusion scores compared with HP stents (P = .026). FDs were significantly more likely to occlude the aneurysm than the branch (P = .01). When the branch was switched to originate from the aneurysm fundus, the FDs became ineffective (0/2). Neointimal closure of the aneurysm ostium was significantly better with FDs than with single or double HP stents (P = .039). Angiographic occlusion correlated with metallic porosity and neointimal tissue coverage (Spearman ρ = -0.81; P = .001). CONCLUSIONS: In this study, flow diverters occluded lateral wall aneurysms more readily than branches. Metal device porosity strongly influenced the occlusion rate.


Subject(s)
Blood Vessel Prosthesis , Disease Models, Animal , Intracranial Aneurysm/physiopathology , Intracranial Aneurysm/surgery , Stents , Animals , Blood Flow Velocity , Dogs , Equipment Design , Equipment Failure Analysis , Humans , Treatment Outcome
16.
AJNR Am J Neuroradiol ; 33(2): 320-2, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22194375

ABSTRACT

BACKGROUND AND PURPOSE: To be radiopaque, BAVM embolization products must contain high-atomic-number materials, which may also attenuate photon beams delivered with radiosurgery. This "shielding effect" has been invoked to explain why radiation therapy may be less effective for previously embolized BAVMs. To evaluate the impact of embolization material on radiation dose, we measured and compared the dose delivered to the center of an AVM model, before and following embolization with various materials in a LINAC. MATERIALS AND METHODS: Two in vitro AVM models were constructed by drilling interconnected tubular perforations in plastic water phantoms to simulate nidal vessels. Phantoms were designed to allow the positioning of a radiation detector at their center. One model was embolized with Onyx 18 and a second model, with a combination of Indermil, Lipiodol, tungsten powder, and Onyx 18. The radiation delivered was compared between embolized and nonembolized controls following irradiation with a standard 250-cGy dose. RESULTS: The mean dose of radiation delivered to the model embolized with Onyx alone was 244 ± 5 cGy before and 246 ± 5 cGy following embolization. The mean dose of radiation delivered to the model embolized with various agents was 242 ± 5 cGy before, and 254 ± 5 cGy after embolization. CONCLUSIONS: Embolic material did not reduce the radiation dose delivered by a LINAC to the center of our experimental BAVM models. The shielding effect may be compensated by scattered and reflected radiation.


Subject(s)
Embolization, Therapeutic/methods , Intracranial Arteriovenous Malformations/therapy , Radiotherapy Dosage , Models, Anatomic
17.
AJNR Am J Neuroradiol ; 33(4): 626-31, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22194386

ABSTRACT

BACKGROUND AND PURPOSE: Angiographic results are commonly used as a surrogate marker of success of coiling of intracranial aneurysms. Inter- and intraobserver agreement in judging angiographic results remain poorly characterized. Our goal was to offer such an evaluation of a grading scale commonly used to evaluate results of endovascular treatment of aneurysms. MATERIALS AND METHODS: A portfolio of 90 angiographic images from 45 patients selected from the core lab data base of a randomized trial was sent to 12 observers on 2 occasions more than 3 months apart. The variability of a 3-value grading scale used to score angiographic results and of a final judgment regarding the presence of a recurrence was studied using κ statistics. RESULTS: Ten participants responded once and 6 responded twice. Agreement was poor to moderate (κ = 0.28-0.5) for senior and junior observers judging angiographic results immediately or 12-18 months after treatment. Agreement reached a reassuring "substantial" (κ = 0.62) level, with a dichotomous presence-absence of a major recurrence, and intraobserver agreement was better in experienced core lab assessors. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments, rendering comparisons between publications risky, if not invalid. A simple dichotomous judgment can be used as a surrogate outcome in randomized trials designed to assess the value of new endovascular devices.


Subject(s)
Cerebral Angiography , Endovascular Procedures/instrumentation , Endovascular Procedures/methods , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Mechanical Thrombolysis/instrumentation , Adult , Aged , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Sensitivity and Specificity , Treatment Outcome
18.
AJNR Am J Neuroradiol ; 32(11): 2175-9, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21920868

ABSTRACT

BACKGROUND AND PURPOSE: FDs are the latest, most promising tool to treat giant and complex aneurysms. Currently available experimental aneurysm models do not reproduce the potential clinical difficulties of treating these lesions with FDs. MATERIALS AND METHODS: Six large or giant canine fusiform aneurysms were created on the distal carotid arteries of 4 animals. Four of the aneurysms had multiple arterial branches originating from the aneurysm; 2 other aneurysms had all branches clipped at the time of aneurysm construction. Aneurysms were treated with multiple telescoping prototype flow-diverting stents (total of 15 FDs). Angiography was carried out before and immediately after implantation, at 2 weeks, and immediately before sacrifice at 12 weeks. Macroscopic photography of specimens was performed, followed by biopsies of selected regions of the tissue formed on the surface of FDs. RESULTS: Technical or device-related difficulties occurred in 2 of 6 aneurysm treatments. Fusiform aneurysms with branches intact remained widely patent (mean angiographic score, 3), whereas aneurysms with clipped branches had only small residua (mean angiographic score, 1) at 12 weeks. The presence of very small defects in neointima formation on the surface of FDs, or leaks, was sufficient for residual filling of the aneurysms, which served as reservoirs to feed branches. CONCLUSIONS: Experimental canine fusiform carotid aneurysms may reproduce many of the difficulties associated with the treatment of giant aneurysms and could be appropriate for preclinical testing of FD stents.


Subject(s)
Aneurysm/diagnosis , Aneurysm/surgery , Disease Models, Animal , Prosthesis Failure , Vascular Grafting/instrumentation , Vascular Grafting/methods , Animals , Dogs , Equipment Failure Analysis , Humans , Prosthesis Design
19.
J Neuroradiol ; 38(1): 53-61, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20554324

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate retrospectively whether cerebral blood volume measurement based on pretreatment perfusion MRI is a prognostic biomarker for survival in patients with oligodendroglioma or mixed oligoastrocytoma. PATIENTS AND METHODS: Between 1998 and 2004, 54 patients (23 females and 31 males), aged 21-73 years, with oligodendroglioma (or mixed tumour) were examined prior to beginning treatment with dynamic susceptibility-weighted contrast (DSC) perfusion MRI during gadolinium first-pass. The relative cerebral blood volume (rCBV) was calculated by dividing the measurement within the tumour by the measurement of the normal-appearing contralateral region. Patients were classified in two groups, grade A and grade B, according to the Saint-Anne Hospital classification and followed-up clinically and by means of MRI until their death or for a minimum of 5 years. Patients were also classified in grade II and grade III-IV, according to the World Health Organisation (WHO) classification, and were analysed with the same methods. Age, sex, treatment, tumour grade, contrast agent uptake, and rCBV were tested using survival curves with Kaplan-Meier's method, and their differences were analysed using the log-rank test. RESULTS: In this population, median survival was 3 years. A rCBV threshold value of 2.2 was validated as a prognostic factor, for survival in these patients with oligodendrogliomas. Age, sex, contrast uptake, and maximum rCBV were found to be prognostic factors in univariate analysis. Multivariate analysis revealed that tumour grade (grade A/grade B), rCBV, age, and sex were prognostic factors independent of the other factors. The tumour grade according to the WHO classification (II versus III-IV) was also detected as an independent prognostic factor. CONCLUSION: Pretreatment rCBV measured by DSC perfusion MRI was found to be a prognostic factor for survival in patients with oligodendroglioma or mixed tumour, by using the Saint-Anne Hospital classification, which separate the IIB from the IIA.


Subject(s)
Blood Volume , Brain Neoplasms/mortality , Brain/physiopathology , Magnetic Resonance Angiography , Oligodendroglioma/mortality , Adult , Aged , Blood Volume Determination , Brain/pathology , Brain Neoplasms/pathology , Brain Neoplasms/physiopathology , Female , Humans , Male , Middle Aged , Oligodendroglioma/pathology , Oligodendroglioma/physiopathology , Predictive Value of Tests , Prognosis , ROC Curve , Retrospective Studies
20.
J Neuroradiol ; 36(5): 265-9, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19251321

ABSTRACT

PURPOSE: To describe transvenous embolization in four patients with indirect dural carotid cavernous fistulas (CCFs) via the inferior petrosal sinus (IPS) or superior ophthalmic vein (SOV), and their clinical outcomes. METHODS: The CCF approach was performed after retrograde venous catheterization from the femoral vein to the cavernous sinus via the IPS (n=1) or SOV (n=3). SOV catheterization was possible without surgical intervention. All patients presented initially with typical clinical signs of CCF. Patients treated via the SOV presented with thrombosis of the IPS. RESULTS: Catheterization and embolization were successful in all patients, with complete angiographic occlusion of the fistula. No early or late complications occurred. All patients presented with favorable clinical outcomes and complete recovery of ocular symptoms. CONCLUSION: Retrograde transvenous embolization of CCF via the IPS, or SOV if the IPS is thrombosed, is a safe procedure with a good clinical outcome.


Subject(s)
Carotid-Cavernous Sinus Fistula/therapy , Catheterization/methods , Cavernous Sinus/surgery , Embolization, Therapeutic/methods , Aged , Aged, 80 and over , Angiography , Carotid Arteries/diagnostic imaging , Carotid Arteries/pathology , Carotid-Cavernous Sinus Fistula/complications , Carotid-Cavernous Sinus Fistula/pathology , Female , Femoral Vein , Functional Laterality , Humans , Middle Aged , Oculomotor Nerve Diseases/etiology , Oculomotor Nerve Diseases/pathology , Oculomotor Nerve Diseases/therapy , Thrombosis/pathology , Thrombosis/therapy , Tomography, X-Ray Computed , Treatment Outcome , Vision Disorders/etiology , Vision Disorders/pathology , Vision Disorders/therapy
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