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Noninvasive Imaging (noninvasive + imaging)
Terms modified by Noninvasive Imaging Selected AbstractsNoninvasive Imaging, Treatment, and Microscopic Confirmation of Clearance of Basal Cell CarcinomaDERMATOLOGIC SURGERY, Issue 3 2003Mark Goldgeier MD BACKGROUND. The diagnosis of basal cell carcinoma (BCC) is generally established by skin biopsy followed by tissue preparation and microscopic analysis. Treatment of BCC is often accomplished by surgical excision. Objective. To confirm the presence of BCC with a noninvasive imaging technique, to treat the patient with a topical immune response modifier, and to confirm the clearance of BCC noninvasively. METHODS. Confocal microscopy (CM) is a noninvasive technique for real-time imaging of skin in vivo. Imiquimod, an immune response modifier, is applied topically by the patient to the skin lesion. RESULTS. The presence of BCC was confirmed with CM. Posttreatment CM imaging confirmed the clearance of BCC from the entire treatment field. Both the pretreatment and the posttreatment CM findings were confirmed by invasive biopsy. CONCLUSION. The ability to use CM to image in real time without discomfort to the patient makes it a powerful tool to assist in the diagnosis of skin disease. [source] Noninvasive Imaging of Angiogenesis Inhibition Following Nitric Oxide Synthase Blockade in the Ischemic Rat Heart in VivoMICROCIRCULATION, Issue 4 2005CHRISTIANE WALLER MD ABSTRACT Objective: Nitric oxide synthase inhibition has anti-angiogenic properties. Magnetic resonance (MR) imaging was used to image the functional significance of these microvascular changes in a rat model of chronic ischemic myocardium in vivo. Methods: The authors quantitatively determined myocardial perfusion and regional blood volume, left ventricular geometry, and function using MR imaging. Animals received either L-NAME + hydralazine or no treatment and were investigated 1 and 2 weeks after induction of coronary artery stenosis or sham operation at rest and during vasodilatation. Double-labeling immunohistochemistry was used to visualize angiogenesis and to compare with data obtained by MR imaging. Results: Left ventricular mass and end-diastolic volumes were comparable in both groups 2 weeks after treatment. However, basal and maximum perfusion in animals with L -NAME + hydralazine treatment were reduced compared to animals not treated (p < .05). Basal regional blood volume remained constant in all groups, whereas maximum regional blood volume was reduced by L -NAME + hydralazine (p < .05). Endothelial cell proliferation, a direct marker for angiogenesis, was reduced by L -NAME + hydralazine (p < .01). Conclusions: MR imaging allows noninvasive quantification of functional microcirculation and angiogenesis in the rat heart in vivo. Nitric oxide synthase blockade results in changes in functional microcirculation and in an inhibition of angiogenesis in both ischemic and nonischemic myocardial tissue. [source] Challenges Facing Validation of Noninvasive Electrical Imaging of the HeartANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2005Martyn P. Nash Ph.D. Noninvasive imaging of regional cardiac electrophysiology remains an elusive target. Such imaging is still in its infancy, particularly in comparison to structural imaging modalities such as magnetic resonance imaging (MRI), x-ray computed tomography (CT), and ultrasound. We present an overview of noninvasive ECG imaging, and the challenges and successes of the various techniques across a range of applications. Unlike MRI and CT, reconstructing cardiac electrophysiology from remote body surface measurements is a highly ill-posed problem. We therefore first review the theoretical considerations and associated algorithms that are used to address this issue. We then focus on the important issue of validation, and review and contrast recent advances in this area. Efforts to validate ECG inverse procedures using a modeling-based approach are addressed first. We then discuss various experimental studies that have been conducted to provide appropriate data for robust validations. We present new data that are simultaneously recorded from dense arrays of electrodes on the epicardium and body surface of anesthetized pigs during sinus rhythm, ventricular pacing, and regional ischemia. These data have been obtained specifically to help validate inverse ECG procedures, and form a useful supplement to recent clinical validation studies. Finally, clinical applications and outstanding issues regarding noninvasive imaging of regional cardiac electrophysiology are addressed. [source] Detection of different tumor growth kinetics in single transgenic mice with oncogene-induced mammary carcinomas by flat-panel volume computed tomographyINTERNATIONAL JOURNAL OF CANCER, Issue 1 2009Katharina Jannasch Abstract Transgenic mouse models offer an excellent opportunity for studying the molecular basis of cancer development and progression. Here we applied flat-panel volume computed tomography (fpVCT) to monitor tumor progression as well as the development of tumor vasculature in vivo in a transgenic mouse model for oncogene-induced mammary carcinogenesis (WAP-T mice). WAP-T mice develop multiple mammary carcinomas on oncogene induction within 3 to 5 months. Following induction, 3-dimensional fpVCT data sets were obtained by serial single scans of entire mice in combination with iodine containing contrast agents and served as basis for precise measurements of tumor volumes. Thereby, we were able to depict tumors within the mammary glands at a very early stage of the development. Tumors of small sizes (0.001 cm3) were detected by fpVCT before being palpable or visible by inspection. The capability to determine early tumor onset combined with longitudinal noninvasive imaging identified diverse time points of tumor onset for each mammary carcinoma and different tumor growth kinetics for multiple breast carcinomas that developed in single mice. Furthermore, blood supply to the breast tumors, as well as blood vessels around and within the tumors, were clearly visible over time by fpVCT. Three-dimensional visualization of tumor vessels in high resolution was enhanced by the use of a novel blood pool contrast agent. Here, we demonstrate by longitudinal fpVCT imaging that mammary carcinomas develop at different time points in each WAP-T mouse, and thereafter show divergent growth rates and distinct vascularization patterns. © 2009 UICC [source] Contemporary management of pulmonary embolism: the answers to ten questionsJOURNAL OF INTERNAL MEDICINE, Issue 3 2010H. Bounameaux Abstract., Bounameaux H (Division of Angiology and Hemostasis, Department of Internal Medicine, University Hospitals of Geneva and Faculty of Medicine, Geneva, Switzerland). Contemporary management of pulmonary embolism: the answers to ten questions (Review). J Intern Med 2010; 268: 218,231. Pulmonary embolism (PE) cannot be diagnosed solely on a clinical basis, because of the lack of sensitivity and specificity of clinical signs and symptoms. Pulmonary angiography is invasive and resource demanding. Because the prevalence of PE is relatively low (20% or less) amongst individuals who are clinically suspected of having the disease, submitting all of them to imaging (multi-detector CT angiography or ventilation/perfusion lung scintigraphy) would not be cost-effective. Therefore, diagnostic algorithms have been developed that include clinical probability assessment and D-dimer measurement to select the patients who require noninvasive imaging. Once the diagnosis is suspected or confirmed, therapy must be started to avoid potentially fatal recurrence. Treatment starts for an initial 3-month period with a 5-day course of parenteral unfractionated or low-molecular-weight heparin or fondaparinux overlapping with and followed by oral vitamin K antagonists monitored to maintain an international normalized ratio of 2,3. This initial period of 3 months may then be followed by a long-term secondary prevention period in patients who experience an idiopathic thromboembolic event and are at low risk of bleeding. New oral anticoagulants that do require patient monitoring and might exhibit a more favourable benefit,risk balance are currently under extensive clinical testing and might change the situation in the near future. A critical appraisal of the contemporary management of suspected PE is given in this overview with the discussion of 10 practical questions. [source] Efficacy and Safety of Absorbable Metallic Stents with Adjunct Intracoronary Beta Radiation in Porcine Coronary ArteriesJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2007F.A.C.C., RON WAKSMAN M.D. Background: Absorbable metallic stents (AMS) utilizing Mg alloy carry advantages over permanent metallic stents because of their potential to eliminate stent thrombosis, chronic inflammation, or artifacts with noninvasive imaging. These stents, however, are associated with a modest degree of late recoil and intimal hyperplasia. The aim of the study was to test whether adjunct vascular brachytherapy (VBT) compared to AMS alone can overcome these limitations. Methods: Juvenile domestic pig coronary arteries underwent implantation of either AMS (n = 11) with prior adjunct VBT utilizing Sr/Y-90 , source seeds, with a dose of 24 Gy at 2 mm from the source, or AMS alone (n = 11). At 28 days following intravascular ultrasound, vessels were harvested and analyzed by histomorphometry. Results: Intravascular ultrasound analysis indicated that at follow-up, though statistically not significant, lumen and stent areas in the segments deployed with AMS following radiation were larger than those deployed with AMS alone (3.94 ± 1.38 and 3.53 ± 1.75 vs. 2.99 ± 1.05 and 3.58 ± 1.48). Extrastent plaque and intrastent plaque areas in the same segments were smaller (2.76 ± 0.82 and 0.24 ± 0.47 vs. 3.25 ± 1.94 and 0.58 ± 0.81). Morphometric data indicate that vessels in the VBT + AMS group showed characteristics of delayed healing and re-endothelialization. Neointimal area was significantly lower in the VBT + AMS group (0.49 ± 0.34) compared to AMS (1.3 ± 0.62, P = 0.001). Lumen area of the VBT + AMS was larger when compared with AMS alone (2.49 ± 0.82 vs. 1.75 ± 0.51, P = 0.02). Conclusion: VBT as an adjunct to AMS further reduces the intimal hyperplasia and improves the lumen area when compared to AMS alone but does not have any impact on late recoil. [source] Improving the Procedure for Detection of Intrahepatic Transplanted Islets by Magnetic Resonance ImagingAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2009M. L. Malosio Islet transplantation is an effective therapy for restoring normoglycemia in type-1 diabetes, but long-term islet graft function is achieved only in a minority of cases. Noninvasive magnetic resonance imaging of pancreatic islets is an attractive option for "real-time" monitoring of graft evolution. So far, previous studies have been performed in the absence of a standardized labeling procedure and, besides a feasibility study in patients, the effectiveness and safety of various labeling approaches were tested only with high field magnets (4.7 T). In this study, we addressed: (a) standardization of a labeling procedure for human islets with clinically-approved contrast agent Endorem®, (b) safety aspects of labeling related to inflammation and (c) quality of imaging both at 7 T and 1.5 T. We have highlighted that the ratio of Endorem®/islet is crucial for reproducible labeling, with a ratio of 2.24 ug/IEQ, allowing successful in vivo imaging both with 1.5 T and 7.0 T magnets up to 143 days after intrahepatic transplant. With this standardized labeling procedure, labeled islets are neither inflamed nor more susceptible to inflammatory insults than unlabeled ones. This report represents an important contribution towards the development of a standardized and safe clinical protocol for the noninvasive imaging of transplanted islets in humans. [source] Sodium imaging intensity increases with time after human ischemic stroke,ANNALS OF NEUROLOGY, Issue 1 2009Muhammad S. Hussain MD Objective Establishing time of onset is important in acute stroke management. Current imaging modalities do not allow determination of stroke onset time. Although correlations between sodium magnetic resonance imaging signal intensity within ischemic lesions and time of onset have been shown in animal models, the relation to onset time has not been established in human stroke. Utilizing high-quality sodium images, we tested the hypothesis that sodium signal intensity increases with time from symptom onset in human ischemic stroke. Methods Twenty-one stroke patients (63 ± 15 years old) were scanned 4 to 104 hours after symptom onset. Follow-up images were obtained in 10 patients at 23 to 161 hours after onset, yielding a total of 32 time points. A standard stroke imaging protocol was acquired at 1.5 Tesla, followed by sodium magnetic resonance imaging at 4.7 Tesla. Relative sodium signal intensity within each lesion was measured with respect to the contralateral side. Results The sodium image quality was sufficient to visualize each acute lesion (lesion volume range, 1.7,217cm3). Relative sodium signal intensity increased nonlinearly over time after stroke onset. Sodium images acquired within 7 hours (n = 5) demonstrated a relative increase in lesion intensity of 10% or less, whereas the majority beyond 9 hours demonstrated increases of 23% or more, with an eventual leveling at 69 ± 18%. Interpretation Increases of sodium signal intensity within the ischemic lesion are related to time after stroke onset. Thus, noninvasive imaging of sodium may be a novel metabolic biomarker related to stroke progression. Ann Neurol 2009;66:55,62 [source] Challenges Facing Validation of Noninvasive Electrical Imaging of the HeartANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2005Martyn P. Nash Ph.D. Noninvasive imaging of regional cardiac electrophysiology remains an elusive target. Such imaging is still in its infancy, particularly in comparison to structural imaging modalities such as magnetic resonance imaging (MRI), x-ray computed tomography (CT), and ultrasound. We present an overview of noninvasive ECG imaging, and the challenges and successes of the various techniques across a range of applications. Unlike MRI and CT, reconstructing cardiac electrophysiology from remote body surface measurements is a highly ill-posed problem. We therefore first review the theoretical considerations and associated algorithms that are used to address this issue. We then focus on the important issue of validation, and review and contrast recent advances in this area. Efforts to validate ECG inverse procedures using a modeling-based approach are addressed first. We then discuss various experimental studies that have been conducted to provide appropriate data for robust validations. We present new data that are simultaneously recorded from dense arrays of electrodes on the epicardium and body surface of anesthetized pigs during sinus rhythm, ventricular pacing, and regional ischemia. These data have been obtained specifically to help validate inverse ECG procedures, and form a useful supplement to recent clinical validation studies. Finally, clinical applications and outstanding issues regarding noninvasive imaging of regional cardiac electrophysiology are addressed. [source] | ||||||||||