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Sample records for intravascular contrast agent-enhanced

  1. Contrast agent enhanced pQCT of articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Kallioniemi, A S [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Jurvelin, J S [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Nieminen, M T [Department of Diagnostic Radiology, POB 50, 90029 OYS, Oulu University Hospital, Oulu (Finland); Lammi, M J [Department of Anatomy, Institute of Biomedicine, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Toeyraes, J [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland)

    2007-02-21

    The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T{sub 1,Gd} and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally

  2. Contrast agent enhanced pQCT of articular cartilage

    Science.gov (United States)

    Kallioniemi, A. S.; Jurvelin, J. S.; Nieminen, M. T.; Lammi, M. J.; Töyräs, J.

    2007-02-01

    The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T1,Gd and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n = 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r = -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally

  3. Contrast agent enhanced pQCT of articular cartilage

    International Nuclear Information System (INIS)

    Kallioniemi, A S; Jurvelin, J S; Nieminen, M T; Lammi, M J; Toeyraes, J

    2007-01-01

    The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T 1,Gd and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally degraded

  4. Death following intravascular administration of contrast media

    International Nuclear Information System (INIS)

    Shehadi, W.H.

    1985-01-01

    Adverse reactions to intravascularly administered contrast media preceding death and the autopsy findings in 44 patients are presented. There is a wide scatter of the age distribution of fatal reactions. The highest incidence is in the 50-70 year age group. Similar observations were obtained from the 405 deaths due to contrast media reported to the Food and Drug Administration of the United States. In the same age group the number of reactions is highest, likewise the autopsy findings. The predominant autopsy findings are pulmonary edema, congestion and hemorrhage; arteriosclerosis, both general and coronary. In the younger age group the autopsy findings are limited mostly to the respiratory tract. Fatal reactions to contrast media occur often without warning and most deaths occur within 15 min to 6 hours. Reactions to contrast media occur without relation to sex or age. (orig.)

  5. Role of informed consent for intravascular contrast media

    International Nuclear Information System (INIS)

    Hopper, K.D.; Tyler, H.N. Jr.

    1988-01-01

    To evaluate the usefulness of different degrees of informed consent for intravascular contrast media, the authors divided 100 patients into four groups: (1) informed consent with no information on intravascular contrast media, (2) simple written informed consent that detailed common risks, (3) detailed written informed consent that detailed all known risks, and (4) MD informed consent, during which a radiologist discussed all known risks of intravascular contrast media. Physician counseling time for group 4 averaged 11.4 minutes. On a postprocedure test about the common complications and risk factors of intravascular contrast media, the average scores were: group 1, 38.4%; group 2, 68.2%; group 3, 63.2%; and group 4, 69.8%. There was no statistical difference between groups 2-4 on the postprocedure test. If informed consent is to be used prior to intravascular contrast media administration, a simple written consent detailing the common risks and risk factors appears to be the best method

  6. Gaucher disease in the liver on hepatocyte specific contrast agent enhanced MR imaging

    International Nuclear Information System (INIS)

    Ayyala, Rama S.; Teot, Lisa A.; Perez Rossello, Jeanette M.

    2017-01-01

    Gaucher disease is a hereditary lipid storage disorder that affects the enzyme beta glucocerebrosidase, causing accumulation of glucocerebroside in macrophages of the reticuloendothelial system. Accumulation can occur in the liver and spleen, manifesting as hepatosplenomegaly, as well as within the bone marrow. Hepatic involvement is usually diffuse but can occasionally manifest as focal liver lesions. We present a case of a 2-year-old boy with Gaucher disease and an infiltrating liver lesion detected on imaging, which was pathologically shown to be focal changes related to the disease. Imaging characteristics of this lesion using hepatocyte specific contrast agent enhanced MRI, which have not been previously discussed in the literature, are described. (orig.)

  7. Gaucher disease in the liver on hepatocyte specific contrast agent enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ayyala, Rama S. [Morgan Stanley Children' s Hospital, Department of Radiology, Columbia University Medical Center, New York, NY (United States); Teot, Lisa A. [Boston Children' s Hospital, Department of Pathology, Harvard Medical School, Boston, MA (United States); Perez Rossello, Jeanette M. [Boston Children' s Hospital, Department of Radiology, Harvard Medical School, Boston, MA (United States)

    2017-04-15

    Gaucher disease is a hereditary lipid storage disorder that affects the enzyme beta glucocerebrosidase, causing accumulation of glucocerebroside in macrophages of the reticuloendothelial system. Accumulation can occur in the liver and spleen, manifesting as hepatosplenomegaly, as well as within the bone marrow. Hepatic involvement is usually diffuse but can occasionally manifest as focal liver lesions. We present a case of a 2-year-old boy with Gaucher disease and an infiltrating liver lesion detected on imaging, which was pathologically shown to be focal changes related to the disease. Imaging characteristics of this lesion using hepatocyte specific contrast agent enhanced MRI, which have not been previously discussed in the literature, are described. (orig.)

  8. Adverse reactions to intravascularly administered contrast media

    International Nuclear Information System (INIS)

    Olin, T.

    1986-01-01

    A hypothesis is formulated about the mechanisms causing adverse reactions to contrast media. Contrast media act in two ways. They stimulate the mast cells to release histamine and leukotrienes, and they inhibit the enzymes which otherwise degrade leukotrienes. Thus individuals, especially those with a history of allergy, are easily exposed to undue amounts of leukotrienes and these are responsible for the adverse reactions. (orig.)

  9. Contrast agent incompatibility with intravascular medications

    International Nuclear Information System (INIS)

    Irving, H.D.; Burbridge, B.E.

    1988-01-01

    In vitro and in vivo precipitation of iodinated contrast agents with commonly used medications have been reported. The intent of this in vitro study is to verify these reports and investigate other medications not previously tested. Contrast agents and medications were analyzed with a light spectrometer and observed for visible precipitates for up to 120 minutes. Previously reported incompatibilities were verified, and several new incompatibilities were discovered

  10. Contrast Agent-Enhanced Computed Tomography of Articular Cartilage: Association with Tissue Composition and Properties

    International Nuclear Information System (INIS)

    Silvast, T. S.; Jurvelin, J.S.; Aula, A.S.; Lammi, M.J.; Toeyraes, J.

    2009-01-01

    Background: Contrast agent-enhanced computed tomography may enable the noninvasive quantification of glycosaminoglycan (GAG) content of articular cartilage. It has been reported that penetration of the negatively charged contrast agent ioxaglate (Hexabrix) increases significantly after enzymatic degradation of GAGs. However, it is not known whether spontaneous degradation of articular cartilage can be quantitatively detected with this technique. Purpose: To investigate the diagnostic potential of contrast agent-enhanced cartilage tomography (CECT) in quantification of GAG concentration in normal and spontaneously degenerated articular cartilage by means of clinical peripheral quantitative computed tomography (pQCT). Material and Methods: In this in vitro study, normal and spontaneously degenerated adult bovine cartilage (n=32) was used. Bovine patellar cartilage samples were immersed in 21 mM contrast agent (Hexabrix) solution for 24 hours at room temperature. After immersion, the samples were scanned with a clinical pQCT instrument. From pQCT images, the contrast agent concentration in superficial as well as in full-thickness cartilage was calculated. Histological and functional integrity of the samples was quantified with histochemical and mechanical reference measurements extracted from our earlier study. Results: Full diffusion of contrast agent into the deep cartilage was found to take over 8 hours. As compared to normal cartilage, a significant increase (11%, P 0.5, P<0.01). Further, pQCT could be used to measure the thickness of patellar cartilage. Conclusion: The present results suggest that CECT can be used to diagnose proteoglycan depletion in spontaneously degenerated articular cartilage with a clinical pQCT scanner. Possibly, the in vivo use of clinical pQCT for CECT arthrography of human joints is feasible

  11. Prevention of adverse reactions to intravascular contrast media

    International Nuclear Information System (INIS)

    Soyer, P.; Levesque, M.

    1990-01-01

    The exact mechanisms of adverse reactions to contrast media are still imperfectly known. However, these reactions may be classified as idiosyncratic. Non-idiosyncratic reactions can be prevented by using new, non-ionic contrast agents. Idiosyncratic reactions can be prevented by specific premedication. Patients with a history of idiosyncratic reaction may benefit from corticosteroids and antihistamines administered prophylactically. Patients who seem to be more likely than others to react to contrast media must be premedicated, the risk of reaction being identified and evaluated by questioning. It has recently been suggested that all patients about to receive an intravascular injection of contrast medium should also be premedicated [fr

  12. Late adverse reactions to intravascular iodinated contrast media

    International Nuclear Information System (INIS)

    Webb, Judith A.W.; Stacul, Fulvio; Thomsen, Henrik S.; Morcos, Sameh K.

    2003-01-01

    Late adverse reactions to intravascular iodinated contrast media are defined as reactions occurring 1 h to 1 week after contrast medium injection. They have received increasing interest over the past decade, but their prevalence remains uncertain and their pathophysiology is not fully understood. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and to issue guidelines. An extensive literature search was carried out and summarized in a report. Based on the available information, simple guidelines have been drawn up. The report and guidelines were discussed at the 8th European Symposium on Urogenital Radiology in Genoa. Late adverse reactions after intravascular iodinated contrast medium include symptoms such as nausea, vomiting, headache, itching, skin rash, musculoskeletal pain, and fever. A significant proportion of these reactions is unrelated to the contrast medium; however, allergy-like skin reactions are well-documented side effects of contrast media with an incidence of approximately 2%. Late reactions appear to be commoner after non-ionic dimers. The majority of late skin reactions after contrast medium exposure are probably T-cell-mediated allergic reactions. Patients at increased risk of late skin reactions are those with a history of previous contrast medium reaction and those on interleukin-2 treatment. Most skin reactions are self-limiting and resolve within a week. Management is symptomatic and similar to the management of other drug-induced skin reactions. (orig.)

  13. Use of carbon dioxide as an intravascular contrast agent: A review of current literature

    OpenAIRE

    Ali, Fahad; Mangi, Muhammad Asif; Rehman, Hiba; Kaluski, Edo

    2017-01-01

    Use of X-ray contrast allows us to differentiate between two or more adjacent structures on radiographic studies. The X-ray contrast agent can be the one with increase X-ray absorption, like iodine and a barium X-ray contrast agent or the one with decrease X-ray absorption like air and carbon dioxide contrast agent. Each contrast agent possesses different risks and benefits in various ways. Carbon dioxide as an intravascular contrast agent can be used as an alternative intravascular contrast ...

  14. Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Jian Wang

    Full Text Available OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9 and II (n = 9 then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg and gadolinium-based macromolecular agent (P792, 15 µmol/kg, respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd

  15. Late adverse reactions to intravascular iodine based contrast media

    DEFF Research Database (Denmark)

    Bellin, Marie-France; Stacul, Fulvio; Webb, Judith A W

    2011-01-01

    DEFINITION: Late adverse reactions (LAR) to contrast media (CM) are defined as reactions occurring 1 h to 1 week after exposure. NEED FOR REVIEW: In view of more prospective studies of LAR and new data about their pathophysiology, the Contrast Medium Safety Committee (CMSC) of the European Societ...

  16. Late adverse reactions to intravascular iodine based contrast media

    DEFF Research Database (Denmark)

    Bellin, Marie-France; Stacul, Fulvio; Webb, Judith A W

    2011-01-01

    DEFINITION: Late adverse reactions (LAR) to contrast media (CM) are defined as reactions occurring 1 h to 1 week after exposure. NEED FOR REVIEW: In view of more prospective studies of LAR and new data about their pathophysiology, the Contrast Medium Safety Committee (CMSC) of the European Society...... or delayed reading intradermal). The main risk factors for LAR are a previous reaction to contrast medium, a history of allergy, and interleukin-2 treatment. Most skin reactions are mild or moderate and self-limiting. MANAGEMENT: Management is symptomatic and similar to the management of other drug......-induced skin reactions. To reduce the risk of repeat reactions avoidance of the relevant CM and any cross-reacting agents identified by skin testing is recommended....

  17. Slow clearance gadolinium-based extracellular and intravascular contrast media for three-dimensional MR angiography.

    Science.gov (United States)

    Bremerich, J; Colet, J M; Giovenzana, G B; Aime, S; Scheffler, K; Laurent, S; Bongartz, G; Muller, R N

    2001-04-01

    The objective of this study was to assess two new slow-clearance contrast media with extracellular and intravascular distribution for magnetic resonance angiography (MRA). Extracellular Gd-DTPA-BC(2)glucA and intravascular Gd(DO3A)(3)-lys(16) were developed within the European Biomed2 MACE Program and compared with two reference compounds, intravascular CMD-A2-Gd-DOTA and extracellular GdDOTA, in 12 rats. Pre- and post-contrast three-dimensional MR (TR/TE = 5 msec/2.2 msec; isotropic voxel size 0.86 mm(3)) was acquired for 2 hours. Signal-to-noise enhancement (DeltaSNR) was calculated. Two minutes after injection, all contrast media provided strong vascular signal enhancement. The DeltaSNR for Gd-DTPA-BC(2)glucA, Gd(DO3A)(3)-lys(16), CMD-A2-Gd-DOTA, and GdDOTA were 13.0 +/- 1.8, 25.0 +/- 3.2, 25.0 +/- 4.0, and 18.0 +/- 3.4, respectively. Gd-DTPA-BC(2)glucA, Gd(DO3A)(3)-lys(16), and CMD-A2-Gd-DOTA cleared slowly from the circulation, whereas GdDOTA cleared rapidly. Vascular DeltaSNR at 2 hours were 2.9 +/- 0.6, 25.0 +/- 3.2, 25.0 +/- 4.0, and 0.4 +/- 1.0. Gd(DO3A)(3)-lys(16) provided strong vascular and minor background enhancement, and thus may be useful for MRA or perfusion imaging. Gd-DTPA-BC(2)glucA produces persistent enhancement of extracellular water, and thus may allow quantification of extracellular distribution volume and assessment of myocardial viability.

  18. The cerebral intravascular enhancement sign is not specific: a contrast-enhanced MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Bakshi, R.; Kinkel, W.R.; Bates, V.E.; Mechtler, L.L.; Kinkel, P.R. [Lucy Dent Imaging Center, University at Buffalo, NY (United States)

    1999-02-01

    The intravascular enhancement (IVE) sign, also known as the ``arterial enhancement sign``, is an abnormal finding in the brain on contrast-enhanced MRI studies. IVE has been described in arterial cerebrovascular disorders, most commonly in acute or subacute arterial ischemic infarcts. However, the specificity of this sign has not been established. We describe four patients with disorders other than arterial strokes in whom gadolinium-enhanced high-field (1.5 T) MRI suggested IVE. The conditions were herpes simplex viral encephalitis, idiopathic cerebellitis, pneumococcal meningitis, and superior sagittal sinus thrombosis with venous infarction. IVE in these cases may be due to multiple factors, including arterial, venous, perivascular, and leptomeningeal or sulcal contrast medium accumulation. Our observations suggest that arterial ischemia, previously described as the cardinal cause of IVE, probably does not explain all instances, and urge caution in interpreting this sign as a specific MRI manifestation of acute arterial infarction or ischemia. (orig.) With 4 figs., 1 tab., 44 refs.

  19. The study of cardiovascular changes by intravascular injection of contrast media

    International Nuclear Information System (INIS)

    Kim, Yang Sook; Park, Chang Yoon

    1986-01-01

    This investigation was aimed to study the effect of contrast media on the cardiovascular system. So in this study, pithed rats were used whether alteration in cardiovascular system by contrast media were controlled centrally. Furthermore, several hypertonic solutions were also used to clarify the effect of contrast media. The results are as follows: 1. Intravenous injection of contrast media in rats (2.5 ml/kg) caused hypotension and bradycardia. The effects were neither blocked by pretreatment of atropine nor pyribenzamine+atropine. 2. NaCI 4.7%, dextrose 24.8%, urea 9.0% and glycerol 10.1% (v/v) which were equiosmolar with contrast media, caused hypotension, but did not affect the heart rate. 3. In pithed rats, intravenous injection of Angiografin increased blood pressure in a dose-dependant manner, and caused decrease in heart rate compared with those of control rats. 4. In pithed rats, bradycardia by intravascular injection with Angiografin was partially blocked by atropine. 5. Metrizamide of which iodine content was adjusted to 280 mg/ml caused increased in blood pressure when was injected intravenously in pithed rats with little effect on heart rate. 6. When perfused with contrast media in rat hindlimb at 15 ml/min./kg speed both perfusion pressure and flow effluent increased, simultaneously. These results suggest that hypotension might be caused by the central effect due to hyperosmolarity of contrast media and bradycardia caused by both parasympathetic stimulation and direct inhibitory action on the cardiac conductive system.

  20. Visualization of Chronic Myocardial Infarction Using the Intravascular Contrast Agent MS-325 (Gadofosveset in Patients

    Directory of Open Access Journals (Sweden)

    Thomas Thouet

    2012-01-01

    Full Text Available Aims. The aim of this study was to evaluate the potential of visualizing chronic myocardial infarction in patients using the intravascular CA MS-325 (gadofosveset, EPIX Pharmaceuticals, Mass, USA. Methods. Nine patients were enrolled in a clinical phase II multicenter trial for MRCA and perfusion imaging using MS-325. They had objective evidence of chronic myocardial infarction as visualized by previously performed late gadolinium (Gd enhancement imaging (LGE with a conventional extracellular Gd-DTPA CA (Magnevist, Bayer Healthcare, Germany, 0.2 mmol/kg/body weight serving as reference standard. A prepulse-optimized LGE study was performed immediately and at several time points after injection of MS-325 (0.05 mmol/kg/body weight. The number and localization of segments demonstrating LGE with MS-325 as well as signal intensities were compared with the reference standard (Gd-DTPA. Results. Using MS-325, LGE could be detected at every time point in all 9 patients. The accuracy of LGE with MS-325 as compared to LGE with Gd-DTPA was highest 54±4 minutes after contrast injection, resulting in a sensitivity of 84% with a specificity of 98%. Conclusion. The intravascular CA MS-325 has the potential to visualize chronic myocardial infarction. However, in comparison with Gd-DTPA, the transmural extent and the number of segments are smaller.

  1. Intravascular enhancement with identical iodine delivery rate using different iodine contrast media in a circulation phantom.

    Science.gov (United States)

    Mihl, Casper; Wildberger, Joachim E; Jurencak, Tomas; Yanniello, Michael J; Nijssen, Estelle C; Kalafut, John F; Nalbantov, Georgi; Mühlenbruch, Georg; Behrendt, Florian F; Das, Marco

    2013-11-01

    Both iodine delivery rate (IDR) and iodine concentration are decisive factors for vascular enhancement in computed tomographic angiography. It is unclear, however, whether the use of high-iodine concentration contrast media is beneficial to lower iodine concentrations when IDR is kept identical. This study evaluates the effect of using different iodine concentrations on intravascular attenuation in a circulation phantom while maintaining a constant IDR. A circulation phantom with a low-pressure venous compartment and a high-pressure arterial compartment simulating physiological circulation parameters was used (heart rate, 60 beats per minute; stroke volume, 60 mL; blood pressure, 120/80 mm Hg). Maintaining a constant IDR (2.0 g/s) and a constant total iodine load (20 g), prewarmed (37°C) contrast media with differing iodine concentrations (240-400 mg/mL) were injected into the phantom using a double-headed power injector. Serial computed tomographic scans at the level of the ascending aorta (AA), the descending aorta (DA), and the left main coronary artery (LM) were obtained. Total amount of contrast volume (milliliters), iodine delivery (grams of iodine), peak flow rate (milliliter per second), and intravascular pressure (pounds per square inch) were monitored using a dedicated data acquisition program. Attenuation values in the AA, the DA, and the LM were constantly measured (Hounsfield unit [HU]). In addition, time-enhancement curves, aortic peak enhancement, and time to peak were determined. All contrast injection protocols resulted in similar attenuation values: the AA (516 [11] to 531 [37] HU), the DA (514 [17] to 531 [32] HU), and the LM (490 [10] to 507 [17] HU). No significant differences were found between the AA, the DA, and the LM for either peak enhancement (all P > 0.05) or mean time to peak (AA, 19.4 [0.58] to 20.1 [1.05] seconds; DA, 21.1 [1.0] to 21.4 [1.15] seconds; LM, 19.8 [0.58] to 20.1 [1.05] seconds). This phantom study demonstrates that

  2. Biliary cystadenoma with bile duct communication depicted on liver-specific contrast agent-enhanced MRI in a child

    Energy Technology Data Exchange (ETDEWEB)

    Marrone, Gianluca; Carollo, Vincenzo; Luca, Angelo [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Diagnostic and Interventional Radiology, Palermo (Italy); Maggiore, Giuseppe [University Hospital S. Chiara, Gastroenterology and Hepatology, Department of Paediatrics, Pisa (Italy); Sonzogni, Aurelio [Riuniti Hospital, Pathology Department, Bergamo (Italy)

    2011-01-15

    Biliary cystadenoma is a benign, but potentially malignant, cystic neoplasm of the biliary ducts occurring most commonly in middle-aged females and very rarely in children. We present a 9-year-old boy with biliary cystadenoma, diagnosed by MRI using a new liver-specific contrast agent (gadoxetic acid) that is eliminated by the biliary system. The images clearly demonstrate the communication between the multiloculated cystic mass and the biliary tree, suggesting the possibility of biliary cystadenoma. Due to the malignant potential of a cystadenoma, the lesion was resected. The resection was complete and the postoperative course was uneventful. (orig.)

  3. Dextran or Saline Can Replace Contrast for Intravascular Optical Coherence Tomography in Lower Extremity Arteries.

    Science.gov (United States)

    Kendrick, Daniel E; Allemang, Matthew T; Gosling, Andre F; Nagavalli, Anil; Kim, Ann H; Nishino, Setsu; Parikh, Sahil A; Bezerra, Hiram G; Kashyap, Vikram S

    2016-10-01

    To examine the hypothesis that alternative flush media could be used for lower extremity optical coherence tomography (OCT) imaging in long lesions that would normally require excessive use of contrast. The OPTical Imaging Measurement of Intravascular Solution Efficacy (OPTIMISE) trial was a single-center, prospective study (ClinicalTrials.gov identifier NCT01743872) that enrolled 23 patients (mean age 68±11 years; 14 men) undergoing endovascular intervention involving the superficial femoral artery. Four flush media (heparinized saline, dextran, carbon dioxide, and contrast) were used in succession in random order for each image pullback. Quality was defined as ≥270° visualization of vessel wall layers from each axial image. Mean proportions (± standard deviation) of image quality for each flush medium were assessed using 1-way analysis of variance and are reported with the 95% confidence intervals (CI). Four OCT catheters failed, leaving 19 patients who completed the OCT imaging protocol; from this cohort, 51 highest quality runs were selected for analysis. Average vessel diameter was 3.99±1.01 mm. OCT imaging allowed 10- to 15-μm resolution of the lumen border, with diminishing quality as vessel diameter increased. Plaque characterization revealed fibrotic lesions. Mean proportions of image quality were dextran 87.2%±12% (95% CI 0.81 to 0.94), heparinized saline 74.3%±24.8% (95% CI 0.66 to 0.93), contrast 70.1%±30.5% (95% CI 0.52 to 0.88), and carbon dioxide 10.0%±10.4% (95% CI 0.00 to 0.26). Dextran, saline, and contrast provided better quality than carbon dioxide (pDextran or saline flush media can allow lesion characterization, avoiding iodinated contrast. Carbon dioxide is inadequate for peripheral OCT imaging. Axial imaging may aid in enhancing durability of peripheral endovascular interventions. © The Author(s) 2016.

  4. Three-dimensional contrast-enhanced MRI using an intravascular contrast agent for detection of traumatic intra-abdominal hemorrhage and abdominal parenchymal injuries: an experimental study

    International Nuclear Information System (INIS)

    Weishaupt, D.; Ruehm, S.G.; Patak, M.A.; Schmidt, M.; Debatin, J.F.; Hetzer, F.H.

    2000-01-01

    The aim of this study was to compare the performance of 3D MRI in conjunction with an intravascular contrast agent to spiral contrast-enhanced CT, regarding the detection of abdominal parenchymal injuries as well as peritoneal hemorrhage in an animal model. Liver and kidney injuries were created surgically in six female pigs under general anesthesia. All pigs underwent contrast-enhanced spiral CT and 3D MR imaging following administration of an intravascular contrast agent (NC100150 Injection). Two readers rated their confidence independently on MR and CT data sets using a five-point scale for the presence of organ injury and hemoperitoneum. Autopsy findings served as standard of reference. Sensitivity and specificity for MR in detecting hepatic and renal injuries as well as hemoperitoneum was 100 %. Computed tomography was less accurate with sensitivity and specificity values of 90 and 94 %, respectively. Receiver operating characteristics (ROC) analysis revealed a higher confidence when interpretation was based on MR images. In an animal model 3D MR imaging in conjunction with an intravascular contrast agent proved highly accurate in detecting and localizing parenchymal injuries to the upper abdomen as well as in detecting intraperitoneal blood collections. (orig.)

  5. Dynamic magnetic resonance angiography of the arteries of the hand. A comparison between an extracellular and an intravascular contrast agent

    International Nuclear Information System (INIS)

    Reisinger, Clemens; Gluecker, Thomas; Jacob, Augustinus Ludwig; Bongartz, Georg; Bilecen, Deniz

    2009-01-01

    The purpose of this study was to compare the image quality of the intravascular contrast agent gadofosveset with the extracellular contrast agent gadoterate meglumine in time-resolved three-dimensional magnetic resonance (MR) angiography of the human arteries of the hand. The value of cuff compression technique for suppression of venous enhancement for both contrast agents was also investigated. Three-dimensional MR angiograms of both hands of 11 healthy volunteers were acquired for each contrast agent at 1.5-T, while subsystolic cuff compression was applied at one side. Quantitative and qualitative evaluation were performed and analyzed with Student's t-test. Visualization of vessels was superior in the images acquired with gadofosveset, especially in the late phases. Quantitative and qualitative evaluation showed significantly higher values for gadofosveset. The cuff compression at the lower arm proved to be an effective method to enhance arterial vessels. In conclusion the blood pool agent gadofosveset is superior for the dynamic imaging of the vessels of the hand when compared with the extracellular contrast agent gadoterate meglumine. To fully utilize the advantages of intravascular contrast agents, venous overlay has to be delayed or reduced, which can be achieved effectively by subsystolic lower arm cuff compression. (orig.)

  6. Repeat survey of current practice regarding corticosteroid prophylaxis for patients at increased risk of adverse reaction to intravascular contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, S. [Department of Radiology, Wishaw General Hospital, Lanarkshire Acute Hospitals NHS Trust, 50, Netherton Street, Wishaw, Lanarkshire ML2 0DP (United Kingdom)]. E-mail: sureshradhakrish@hotmail.com; Manoharan, S. [Department of Radiology, Wishaw General Hospital, Lanarkshire Acute Hospitals NHS Trust, 50, Netherton Street, Wishaw, Lanarkshire ML2 0DP (United Kingdom); Fleet, M. [Department of Radiology, Wishaw General Hospital, Lanarkshire Acute Hospitals NHS Trust, 50, Netherton Street, Wishaw, Lanarkshire ML2 0DP (United Kingdom)

    2005-01-01

    AIM: To compare the findings of a survey undertaken by us in 2002 regarding steroid premedication given in radiology departments to reduce the risk of adverse reactions in patients at increased risk of intravascular contrast media reactions with a similar survey published in 1994 by R. Seymour et al. The high risk patients considered in our survey were patients with history of asthma, drug allergies, hay fever and eczema. MATERIALS AND METHODS: A total of 225 questionnaires were sent to the consultant in charge for audit for radiology departments from the list given by the Royal College of Radiologists. 175 of the 225 questionnaires were returned (response rate 77.8%) and of these 172 were analysed with respect to the type, dose and duration of steroids. RESULTS: Compared to the survey in 1994, it was found that the number of departments who use steroid cover for all category of risk factors had increased compared to previous survey (73.8% in 2002 versus 55.3% in 1994 (p=0.001). There is now almost universal use of non-ionic contrast 98.8% versus 82.4% in 1994 (p=0.001). There is no agreed policy among radiology departments for the need or the dose or duration of steroid cover. CONCLUSION: Despite the more widespread use of non-ionic contrast media, the use of steroid premedication has increased which is contrary to what is expected as the incidence of adverse reaction to non ionic media is less than ionic contrast media.

  7. Effect of different saline chaser volumes and flow rates on intravascular contrast enhancement in CT using a circulation phantom

    International Nuclear Information System (INIS)

    Behrendt, Florian F.; Bruners, Philipp; Keil, Sebastian; Plumhans, Cedric; Mahnken, Andreas H.; Das, Marco; Ackermann, Diana; Guenther, Rolf W.; Muehlenbruch, Georg

    2010-01-01

    Purpose: To evaluate the influence of different saline chaser volumes and different saline chaser flow rates on the intravascular contrast enhancement in MDCT. Materials and methods: In a physiological flow phantom contrast medium (120 ml, 300 mgI/ml, Ultravist 300) was administered at a flow rate of 6 ml/s followed by different saline chaser volumes (0, 30, 60 and 90 ml) at the same injection rate or followed by a 30-ml saline chaser at different injection rates (2, 4, 6 and 8 ml/s). Serial CT-scans at a level covering the pulmonary artery, the ascending and the descending aorta replica were obtained. Time-enhancement curves were computed and both pulmonary and aortic peak enhancement and peak time were determined. Results: Compared to contrast medium injection without a saline chaser the pushing with a saline chaser (30, 60, and 90 ml) resulted in a statistically significant increased pulmonary peak enhancement (all p = 0.008) and prolonged peak time (p = 0.032, p = 0.024 and p = 0.008, respectively). Highest aortic peak enhancement values were detected for a saline chaser volume of 30 ml. A saline chaser flow rate of 8 ml/s resulted in the highest pulmonary peak enhancement values compared to flow rates of 2, 4 and 6 ml/s (all p = 0.008). Aortic peak enhancement showed the highest values for a flow rate of 6 ml/s. Conclusion: A saline chaser volume of 30 ml and an injection rate of 6 ml/s are sufficient to best improve vascular contrast enhancement in the pulmonary artery and the aorta in MDCT.

  8. Patients' oral hydration levels and incidence of immediate to short-term mild side-effects in contrast agent enhanced MRI diagnostics

    International Nuclear Information System (INIS)

    Jonker, Leon; Fallahi, Farshid

    2015-01-01

    Aim: Gadolinium-based contrast agents for radiodiagnostic purposes can lead to side effects, including nephrotoxicity in patients with renal insufficiency. This study evaluated whether the occurrence of mild side effects from gadolinium-based contrast enhanced magnetic resonance imaging (MRI) correlates to patients' oral hydration levels. Methods: Oral fluid intake levels 24 h pre- and 24 h post-MRI, as well as incidence of mild side-effects experienced 30 min and 24 h post-MRI were recorded by using a patient self-reporting questionnaire. Results: A total of 174 patients, 29 controls, 98 administered Prohance and 47 receiving Dotarem, were enrolled. Overall, the most frequently reported side-effect was headache; nausea only occurred in patients receiving contrast agent. One or more side-effects experienced 24 h following the MRI scan were reported by 10% (controls), 24% (Prohance) and 22% (Dotarem) of patients, respectively. Multivariate ordinal regression analysis showed that only male gender (OR 0.24, 95% CI 0.11–0.53) was statistically significantly associated with a decreased incidence of side-effects 30 min after MRI. At 24-h post MRI, a lack of contrast agent (OR 0.40, 95% CI 0.09–1.74) and male gender (OR 0.46, 95% CI 0.19–1.09) were associated with fewer side-effects. Conclusions: The level oral fluid intake before and after undergoing gadolinium-based contrast-enhanced MRI does not appear to markedly affect the incidence of common undesirable mild symptoms experienced shortly after the procedure. Confounding differences between patients in reporting side-effects may contribute to these findings. - Highlights: • We assess the incidence of patient-reported side-effects after contrast-enhanced MRI. • We examine the potential impact of oral hydration levels on side-effects. • Patient reported side-effects are high compared to those reported by clinicians. • Female gender and contrast agent itself are associated with increased side

  9. Intravascular malignant lymphomatosis

    International Nuclear Information System (INIS)

    Martin-Duverneuil, N.; Lafitte, F.; Chiras, J.; Mokhtari, K.; Behin, A.; Hoang-Xuan, K.

    2002-01-01

    Intravascular malignant lymphomatosis is a rare and probably often overlooked disease characterised by massive intravascular proliferation of lymphoid cells, usually with a poor prognosis. CT and MRI appearances are nonspecific; the most suggestive finding being both asymmetrical, bilateral, contrast enhancing high-signal areas on T2 weighting and infarct-like lesions of the cortex and basal ganglia. We report two patients with previously unreported dural and spinal cord involvement. (orig.)

  10. Intravascular malignant lymphomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Duverneuil, N.; Lafitte, F.; Chiras, J. [Service de Neuroradiologie Charcot, Batiment Babinski, Hopital de la Salpetriere, 75013 Paris (France); Mokhtari, K. [Service de Neuropathologie, Hopital de la Salpetriere, 75013 Paris (France); Behin, A.; Hoang-Xuan, K. [Departement de Neurologie, Hopital de la Salpetriere, 75013 Paris (France)

    2002-09-01

    Intravascular malignant lymphomatosis is a rare and probably often overlooked disease characterised by massive intravascular proliferation of lymphoid cells, usually with a poor prognosis. CT and MRI appearances are nonspecific; the most suggestive finding being both asymmetrical, bilateral, contrast enhancing high-signal areas on T2 weighting and infarct-like lesions of the cortex and basal ganglia. We report two patients with previously unreported dural and spinal cord involvement. (orig.)

  11. Development of a conjugated gadolinium and cisplatin-gelatin possessing properties as an intravascular contrast agent for MR imaging

    International Nuclear Information System (INIS)

    Sonoda, Akinaga; Nitta, Norihisa; Ohta, Shinichi; Seko, Ayumi; Jo, Jun-ichiro; Morikawa, Shigehiro; Tabata, Yasuhiko; Takahashi, Masashi; Murata, Kiyoshi

    2009-01-01

    Purpose: The purpose of this study is to create a Gd-DTPA-Gel-Cis compound, which made from gadolinum (Gd), diethylenetriaminepentaacetic acid (DTPA)-dianhydride, cis-diamminedichloroplatinum (Cis) and bovine gelatin (Gel), that makes it possible to visualize Cis as intravascular agent under magnetic resonance imaging (MRI). Materials and methods: The amount of DTPA, Gd, and Cis were titrated to determine the new compound's conjugation ratio with gelatin. Considering these functions, Gd-DTPA-Gel-Cis was synthesized, and its stability in bovine serum was evaluated. In addition, the signal intensity of the diluted sample was measured under 1.5 Tesla MRI. Results: The synthesized 10 mg/ml of Gd-DTPA-Gel-Cis contained 42.84 μg/ml of Gd and 1.53 μg/ml of platinum. Gd-DTPA-Gel-Cis (100 mg/10 ml) enclosed into the cellulose dialysis tubing was placed in 90 ml of bovine serum and shaken reciprocally at 72 stroke/min at 37 deg. C. Partial release of free Pt was shown at 6 and 24 h, but no release of Gd occurred for a 24-h period. And high stability of Gd conjugated to DTPA-Gel-Cis. This result suggests possible anti-tumor effectiveness and high stability of Gd conjugated to DTPA-Gel-Cis. The diluted sample presented high signal intensity under 1.5 Tesla MRI. Conclusion: Gd-DTPA-Gel-Cis has been developed successfully and we have proven its stability and contrast ability in MRI.

  12. Clinical application of intravascular administration of non-ionic, low osmolar contrast agent, Ioversol (Optiray 320) and its side effects comparison with Meglumine Iothalamate (Conray 60)

    International Nuclear Information System (INIS)

    Hong, Hyun Sook; Kim, Dae Ho; Lee, Hae Kyung; Chung, Moo Chan; Choi, Deuk Lin; Kwon, Kuy Hyang; Kim, Ki Jung

    1990-01-01

    Ioversol, the non-ionic, low osmolar contrast agent has been well characterized chemically and in terms of basic toxicity testing. Ioversol has a fomula similar to that of other nonionic agent. We review the results of intravascular use of this contrast agent, compared ionic contrast media(Meglumine Iothalamate (Conray 60)). Each study was assessed for imaging quality,and patients were monitored vital signs, changes of hematology and blood chemistry and urinalysis before and after contrast administration and were observed for occurrence of side effects. A small number of side effects were reported but no clinically significant sequelae in Ioversol group and much less vital sign changes compared with Conray group. There were no significant changes in vital signs related to the use of Ioversol, and no significant alterations in the renal function parameter or other blood chemistry and hematology measurement were encountered in both contrast media. In most cases, the image qualities were good. In conclusion, Ioversol is safe, well tolerated and efficious for use in intravascular contrast agent, and less vital sign changes and side effect than ionic Meglumine Iothalamte, and Ioversol is likely to provide a useful and acceptable alternative to other low osmolar and nonionic contrast agents

  13. Intravascular ultrasound guidance to minimize the use of iodine contrast in percutaneous coronary intervention: the MOZART (Minimizing cOntrast utiliZation With IVUS Guidance in coRonary angioplasTy) randomized controlled trial.

    Science.gov (United States)

    Mariani, José; Guedes, Cristiano; Soares, Paulo; Zalc, Silvio; Campos, Carlos M; Lopes, Augusto C; Spadaro, André G; Perin, Marco A; Filho, Antonio Esteves; Takimura, Celso K; Ribeiro, Expedito; Kalil-Filho, Roberto; Edelman, Elazer R; Serruys, Patrick W; Lemos, Pedro A

    2014-11-01

    The aim of this study was to evaluate the impact of intravascular ultrasound (IVUS) guidance on the final volume of contrast agent used in patients undergoing percutaneous coronary intervention (PCI). To date, few approaches have been described to reduce the final dose of contrast agent in PCIs. We hypothesized that IVUS might serve as an alternative imaging tool to angiography in many steps during PCI, thereby reducing the use of iodine contrast. A total of 83 patients were randomized to angiography-guided PCI or IVUS-guided PCI; both groups were treated according to a pre-defined meticulous procedural strategy. The primary endpoint was the total volume contrast agent used during PCI. Patients were followed clinically for an average of 4 months. The median total volume of contrast was 64.5 ml (interquartile range [IQR]: 42.8 to 97.0 ml; minimum, 19 ml; maximum, 170 ml) in the angiography-guided group versus 20.0 ml (IQR: 12.5 to 30.0 ml; minimum, 3 ml; maximum, 54 ml) in the IVUS-guided group (p MOZART]; NCT01947335). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  14. MDCT angiography of the pulmonary arteries: intravascular contrast enhancement does not depend on iodine concentration when injecting equal amounts of iodine at standardized iodine delivery rates

    International Nuclear Information System (INIS)

    Keil, S.; Plumhans, C.; Behrendt, F.F.; Das, M.; Muehlenbruch, G.; Mahnken, A.H.; Guenther, R.W.; Stanzel, S.; Seidensticker, P.; Knackstedt, C.; Wildberger, J.E.

    2008-01-01

    To compare the impact of iodine concentration using two different contrast materials (CM) at standardized iodine delivery rate (IDR) and overall iodine load in 16-multidetector-row-CT-angiography (MDCTA) of the pulmonary arteries of 192 patients with known or suspected pulmonary embolism. One hundred three patients (group A) received 148 ml of a CM containing 300 mg iodine/ml (Ultravist 300 trademark, BayerScheringPharma) at a flow rate of 4.9 ml/s. Eighty-nine patients (group B) received 120 ml of a CM with a concentration of 370 mg iodine/ml (Ultravist370 trademark) at a flow rate of 4.0 ml/s, resulting in a standardized IDR (∝1.5 gI/s) and the same overall amount of iodine (44.4 g). Both CM injections were followed by a saline chaser. Mean density values were determined in the pulmonary trunk, the ascending and the descending aorta, respectively. Applying repeated-measures ANOVA, no statistically significant differences between both MDCTA protocols were found (p=0.5790): the mean density in the pulmonary trunk was 355±116 Hounsfield Units (group A) and 358±115 (group B). The corresponding values for the ascending and descending aorta were 295±79 (group A) and 284±65 (group B) as well as 272±71 and 262±70. In conclusion, the use of standardized IDR and overall iodine load provides comparable intravascular CM density in pulmonary 16-MDCTA for delivering contrast materials with different iodine concentrations. (orig.)

  15. Assessing intravascular fluid status

    African Journals Online (AJOL)

    The assessment of intravascular fluid volume is a difficult undertaking in both the intensive care unit and theatre situation ... equally applicable to pulmonary capillary wedge pressure. .... airway pressure, the more difficult it becomes to interpret ...

  16. Disseminated intravascular coagulation (DIC)

    Science.gov (United States)

    ... Jr, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice . 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 141. Thachil J, Toh CH. Current concepts in the management of disseminated intravascular coagulation. Thromb Res . 2012;129 ...

  17. Fluorescent Method for Observing Intravascular Bonghan Duct

    Directory of Open Access Journals (Sweden)

    Byung-Cheon Lee

    2005-12-01

    Full Text Available Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of the intra-vascular thread in connection with acupuncture is discussed. Especially, this threadlike duct can be a circulation path for herb-liquid flow, which may provide the scientific mechanism for therapeutic effect of herbal acupuncture.

  18. Intravascular pulmonary metastases

    International Nuclear Information System (INIS)

    Shepard, J.A.O.; Moore, E.H.; Templeton, P.A.; McLoud, T.C.

    1988-01-01

    The diagnosis of intravascular metastatic tumor emboli to the lungs is rarely made. The authors present a characteristic radiographic finding of intravascular lung metastases that they observed in four patients with diagnoses or right atrial myoxoma, invasive renal cell carcinoma, invasive pelvic osteosarcoma, and recurrent pelvic chondrosarcoma. Substantiation of intravascular pulmonary metastases was achieved by means of autopsy, pulmonary artery biopsy, and surgical documentation of tumor invasion of the inferior vena cava or pelvic veins. In all four cases, chest computed tomography (CT) demonstrated branching, beaded opacities extending from the hila into the periphery of the lung in the distribution of pulmonary arteries. In one case, similar findings were observed in magnetic resonance (MR) images of the chest. Follow-up studies in three cases showed progressive enlargement and varicosity of the abnormal pulmonary artery consistent with proliferation of intravascular tumor. In the case of metastatic osteosarcoma, intraluminal ossification was also observed at CT. In three of four cases, pulmonary infarction was demonstrated in the distribution of the abnormal pulmonary arteries seen at CT as small, peripheral, wedge-shaped opacities. The demonstration of progressively dilated and beaded pulmonary arteries in patients with extrathoracic malignancies is suggestive of intravascular lung metastases, particularly when accompanied by peripheral infarction

  19. Assessment of DNA double-strand breaks induced by intravascular iodinated contrast media following in vitro irradiation and in vivo, during paediatric cardiac catheterization.

    Science.gov (United States)

    Gould, Richard; McFadden, Sonyia L; Horn, Simon; Prise, Kevin M; Doyle, Philip; Hughes, Ciara M

    2016-01-01

    Paediatric cardiac catheterizations may result in the administration of substantial amounts of iodinated contrast media and ionizing radiation. The aim of this work was to investigate the effect of iodinated contrast media in combination with in vitro and in vivo X-ray radiation on lymphocyte DNA. Six concentrations of iodine (15, 17.5, 30, 35, 45, and 52.5 mg of iodine per mL blood) represented volumes of iodinated contrast media used in the clinical setting. Blood obtained from healthy volunteers was mixed with iodinated contrast media and exposed to radiation doses commonly used in paediatric cardiac catheterizations (0 mGy, 70 mGy, 140 mGy, 250 mGy and 450 mGy). Control samples contained no iodine. For in vivo experimentation, pre and post blood samples were collected from children undergoing cardiac catheterization, receiving iodine concentrations of up to 51 mg of iodine per mL blood and radiation doses of up to 400 mGy. Fluorescence microscopy was performed to assess γH2AX-foci induction, which corresponded to the number of DNA double-strand breaks. The presence of iodine in vitro resulted in significant increases of DNA double-strand breaks beyond that induced by radiation for ≥ 17.5 mg/mL iodine to blood. The in vivo effects of contrast media on children undergoing cardiac catheterization resulted in a 19% increase in DNA double-strand breaks in children receiving an average concentration of 19 mg/mL iodine to blood. A larger investigation is required to provide further information of the potential benefit of lowering the amount of iodinated contrast media received during X-ray radiation investigations. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Intravascular "mulberry-like" bodies

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Klebe, J G; Henriques, U V

    1988-01-01

    Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesion...... and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis.......Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions...

  1. In vivo cleavage rate of a dextran-bound magnetic resonance imaging contrast agent: preparation and intravascular pharmacokinetic characteristics in the rabbit.

    Science.gov (United States)

    Hals, Petter Arnt; Sontum, Per Christian; Holtz, Eckart; Klaveness, Jo; Rongved, Pål

    2013-02-01

    Earlier described dextran-based contrast agents for magnetic resonance imaging (MRI) comprising the gadolinium chelate diethylenetriamine pentaacetic acid (GdDTPA, 1) have shown significantly shorter in vivo contrast duration in rat than what would be expected from the initial average molecular weight (Mw) of the dextran fraction (71.4 kD). To investigate this further, four dextran fractions with given initial average molecular weight (Mw) of 10.4, 41.0, 71.4 and 580 kD were used as starting material to prepare products 2-5 where one of the carboxylic acid functionalities in GdDTPA was used as a direct covalent ester linker to hydroxyl groups in dextrans. A fifth derivative (6) was an amide-ester bound β-alanine-DTPAGd conjugate with dextran having Mw 71.4 kD. The reference compound GdDTPA (1) and gadoliniumlabelled dextran derivatives 2-6 were injected intravenously in rabbits. Pharmacokinetic parameters showed that when GdDTPA is ester-bound directly to dextran hydroxyls, the cleavage rates of 2-5 were only moderately dependent on the molecular weights of the dextrans, having blood pool half-lives comparable to the low-molecular reference compound (t 1/2,β 0.3 - 0.5 hrs.). Presence of a β-alanine spacer in 6 prolonged the plasma half-life t 1/2,β to 6.9 hours, rendering a blood residence time suitable for blood pool slow release of GdDTPA. Biological cleavage regenerates the clinically acceptable carrier dextran and the β-alanine derivative of GdDTPA, pointing at a clinically acceptable product class for blood-pool contrast in MRI.

  2. Control of asthma for reducing the risk of bronchospasm in asthmatics undergoing general anesthesia and/or intravascular administration of radiographic contrast media.

    Science.gov (United States)

    Liccardi, Gennaro; Salzillo, Antonello; De Blasio, Francesco; D'Amato, Gennaro

    2009-07-01

    It is well known that patients suffering from bronchial asthma undergoing surgical procedures requiring general anesthesia (GA) or the administration of water soluble radiographic contrast media (RCM) have an increased risk of potentially severe bronchospasm. Nevertheless, little attention has been devoted to the possible preventive measures to reduce the occurrence of this potentially life-threatening event. It has been shown that the most important risk factor for bronchospasm during GA induction and/or the use of RCM is represented by a high degree of bronchial hyperreactivity with airway instability not adequately controlled by long-term anti-inflammatory treatment. The aim of this commentary is to underline the need for an accurate clinical and functional evaluation of asthmatics undergoing surgical procedures requiring GA or radiological procedures requiring the administration of RCM, as well as to suggest a stepwise preventive pharmacological approach for reducing the risk of bronchospasm. The authors' suggestions represent clinical experience of the respiratory section of an internal hospital-based working group whose aim is the prevention of asthmatic/anaphylactic/anaphylactoid reactions during the administration of anesthetics and/or RCM. The MEDLINE database was searched with a combination of keywords: general anesthesia, radio contrast media [and] bronchial asthma. The main limitation of this commentary is the scarcity of available literature on this topic. The authors suggest a therapeutic approach before surgical procedures requiring GA and/or RCM administration based on the degree of asthma control as assessed by clinical/functional criteria. In this setting, in addition to the necessity of obtaining the best control of airway reactivity, the authors suggest that an optimal control of asthma symptoms in 'real life' conditions might likely constitute a safety issue in asthmatic patients in the case of emergency procedures.

  3. Intravascular (catheter) MR imaging

    International Nuclear Information System (INIS)

    Cohen, A.M.; Hurst, G.C.; Katz, D.E.; Dverk, J.L.; Wiesen, E.J.; Czerski, L.W.; Malaya, R.; Bellon, E.M.

    1989-01-01

    Intravascular MR probes allow excellent spatial resolution and have the potential to detect arterial wall microstructure. Ultrasonic intravascular probes suggest that detailed morphologic information can assist clinical decision making. Catheter MR probes of 2--7 mm outside diameter (OD) were built of copper wire, Teflon, and parts from standard commercial catheters. The probes were connected to the surface coil receiver input of our Picker VISTA 2055HP 1.5-T imaging system. The extant (linear) body coil was used for transmit. Phantoms were constructed of coaxial glass MR tubes, filled with doped water. Watanabe rabbit aorta and human autopsy iliac artery specimens were examined within 4 hours of excision or stored by freezing. In vivo iliac arteries in dogs under general anesthesia were imaged, with percutaneous placement of the probe. Results are presented

  4. Fluorescent Method for Observing Intravascular Bonghan Duct

    OpenAIRE

    Byung-Cheon Lee; Ku Youn Baik; Hyeon-Min Johng; Baekkyoung Sung; Kyung Soon Soh; Dae-In Kang; Kwang-Sup Soh

    2005-01-01

    Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of ...

  5. Intravascular "mulberry-like" bodies

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Klebe, J G; Henriques, U V

    1988-01-01

    Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions...... and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis....

  6. Interventional and intravascular MR angiography

    International Nuclear Information System (INIS)

    Ladd, M.E.; Debatin, J.F.

    2000-01-01

    Magnetic resonance imaging (MRI) has a number of characteristics which make it attractive for guidance of intravascular therapeutic procedures, including high soft tissue contrast, imaging in any arbitrary oblique plane, lack of ionizing radiation, and the ability to provide functional information, such as flow velocity and volume per unit time. For MR guidance of vascular interventions to be safe, catheters and guidewires must be visualized relative to the vascular system and surrounding tissues. A number of approaches for making instruments visible in an MR environment are presented, including both passive and active techniques. Passive techniques depend on contrast agents or susceptibility artifacts, whereas active techniques, including MR tracking, MR profiling, and active field inhomogeneity, use some form of electrical coil built into the instrument. The potential for obtaining high-resolution images of the vessel wall using coils built into a catheter is also discussed. These images provide the capability to distinguish and identify various plaque components. The additional capabilities of MRI could potentially open up new applications beyond those currently performed under X-ray fluoroscopic guidance. (orig.) [de

  7. Dosimetry in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing 32 P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  8. Intravascular bronchio-alveolar tumor

    International Nuclear Information System (INIS)

    Mata, J.M.; Caceres, J.; Prat, J.; Lopez, J.I.; Velilla, O.

    1991-01-01

    In 1975 Dail and Liebow described the clinical and pathological characteristics of a pulmonary tumor which they dominated intravascular bronchio-alveolar tumor (IVBAT). Our aim is to acquaint radiologists with the existence of this tumor by describing the radiologic findings in 2 patients with IVBAT, 1 with hepatic involvement ant the other with pulmonary osteoarthropathy. (author). 7 refs.; 2 figs

  9. Network flow of mobile agents enhances the evolution of cooperation

    Science.gov (United States)

    Ichinose, G.; Satotani, Y.; Nagatani, T.

    2018-01-01

    We study the effect of contingent movement on the persistence of cooperation on complex networks with empty nodes. Each agent plays the Prisoner's Dilemma game with its neighbors and then it either updates the strategy depending on the payoff difference with neighbors or it moves to another empty node if not satisfied with its own payoff. If no neighboring node is empty, each agent stays at the same site. By extensive evolutionary simulations, we show that the medium density of agents enhances cooperation where the network flow of mobile agents is also medium. Moreover, if the movements of agents are more frequent than the strategy updating, cooperation is further promoted. In scale-free networks, the optimal density for cooperation is lower than other networks because agents get stuck at hubs. Our study suggests that keeping a smooth network flow is significant for the persistence of cooperation in ever-changing societies.

  10. 21 CFR 880.5200 - Intravascular catheter.

    Science.gov (United States)

    2010-04-01

    ... Devices § 880.5200 Intravascular catheter. (a) Identification. An intravascular catheter is a device that consists of a slender tube and any necessary connecting fittings and that is inserted into the patient's vascular system for short term use (less than 30 days) to sample blood, monitor blood pressure, or...

  11. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiovascular intravascular filter. 870.3375... Cardiovascular intravascular filter. (a) Identification. A cardiovascular intravascular filter is an implant that... and Revision of 2/12/90 (K90-1)” and (ii) “Guidance for Cardiovascular Intravascular Filter 510(k...

  12. Dosimetric model for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Flower, E.E.; Stroud, D.B.

    2000-01-01

    Full text: Intravascular brachytherapy has been shown to be a prophylaxis for restenosis. Adventitial macrophages, which are extremely radiosensitive, initiate neointima formation. A model of the dose levels of the treatment range is developed, assuming that the adventitia is the target tissue. If the adventitia receives a dose of less than 10 Gy, it is assumed the treatment will be ineffective. If the dose to any part of the wall is above 30 Gy, it is assumed that the treatment could be detrimental. Hence the treatment range is between 10 and 30 Gy, with 20 Gy being the optimum dosage to the adventitia. An algorithm using numerical integration of published dose kernels calculates the dose at any point surrounding a beta ( 32 P) line source of finite length. Dose profiles were obtained to demonstrate edge effects. For long lesions, the source is often stepped along the artery. Dose changes due to separation or overlapping of sources during source stepping procedures were also determined. Isodose curves were superimposed on intravascular ultrasound images to demonstrate dose levels. For an exposure time of 60 seconds with a 200mCi source, the optimum dose of 20 Gy occurs at a distance 1.94mm from the centre of the source. The upper limit of the treatment dose range (30 Gy) occurs at 1.59mm. The lower limit of the treatment dose range (10 Gy) occurs at 2.7mm. Significant perturbations to the treatment dose range can be caused by non-centering of the source, edge effects and separation or overlapping of sources in stepping procedures. Despite these concerns, many successful procedures have been reported and this implies that the model is over simplified and requires modifications. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  13. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    OpenAIRE

    Kensuke Tashiro, MD; Shuji Yamashita, MD; Mitsunaga Narushima, MD; Isao Koshima, MD; Shimpei Miyamoto, MD

    2017-01-01

    Background:. Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined...

  14. Coagulación intravascular diseminada = Disseminated intravascular coagulation

    Directory of Open Access Journals (Sweden)

    Arango Barrientos, Marcos

    2010-12-01

    Full Text Available La coagulación intravascular diseminada (CID es una entidad clínica frecuente que se presenta como fenómeno secundario a diversas enfermedades entre las cuales se destacan las infecciones graves, las neoplasias y las catástrofes obstétricas. Se caracteriza por una activación difusa y simultánea de los sistemas endógenos de la coagulación y la fibrinólisis. El depósito de pequeños trombos en la circulación conduce finalmente a disfunción orgánica múltiple y en algunos casos a la muerte. Las manifestaciones clínicas pueden incluir fenómenos trombóticos y hemorrágicos. Se ha propuesto un puntaje de fácil aplicación para simplificar el diagnóstico de la entidad. El tratamiento incluye el control específico de la causa subyacente que favorece la aparición de la CID, el soporte con hemoderivados en pacientes con manifestaciones de sangrado y la anticoagulación terapéutica en pacientes con trombosis mayores. El desarrollo de CID es un factor pronóstico adverso que aumenta significativamente la tasa de mortalidad. En este artículo de revisión se incluyen los siguientes aspectos de la CID: historia, epidemiología, clasificación, entidades asociadas, fisiopatología, clínica, diagnóstico, tratamiento y pronóstico.

  15. Dosimetry in intravascular brachytherapy; Calculos dosimetricos em braquiterapia intravascular

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing {sup 32} P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  16. Dosimetry in intravascular brachytherapy; Calculos dosimetricos em braquiterapia intravascular

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing {sup 32} P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  17. Intravascular photoacoustic imaging: a new tool for vulnerable plaque identification.

    Science.gov (United States)

    Jansen, Krista; van Soest, Gijs; van der Steen, Antonius F W

    2014-06-01

    The vulnerable atherosclerotic plaque is believed to be at the root of the majority of acute coronary events. Even though the exact origins of plaque vulnerability remain elusive, the thin-cap fibroatheroma, characterized by a lipid-rich necrotic core covered by a thin fibrous cap, is considered to be the most prominent type of vulnerable plaque. No clinically available imaging technique can characterize atherosclerotic lesions to the extent needed to determine plaque vulnerability prognostically. Intravascular photoacoustic imaging (IVPA) has the potential to take a significant step in that direction by imaging both plaque structure and composition. IVPA is a natural extension of intravascular ultrasound that adds tissue type specificity to the images. IVPA utilizes the optical contrast provided by the differences in the absorption spectra of plaque components to image composition. Its capability to image lipids in human coronary atherosclerosis has been shown extensively ex vivo and has recently been translated to an in vivo animal model. Other disease markers that have been successfully targeted are calcium and inflammatory markers, such as macrophages and matrix metalloproteinase; the latter two through application of exogenous contrast agents. By simultaneously displaying plaque morphology and composition, IVPA can provide a powerful prognostic marker for disease progression, and as such has the potential to transform the current practice in percutaneous coronary intervention. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  18. Novel approaches to the management of disseminated intravascular coagulation

    NARCIS (Netherlands)

    Levi, M. [=Marcel M.; de Jonge, E.; van der Poll, T.; ten Cate, H.

    2000-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to widespread deposition of fibrin in the circulation. We addressed the issue of whether there is evidence that this fibrin deposition contributes to multiple organ

  19. Quinine-induced disseminated intravascular coagulation.

    Science.gov (United States)

    Spearing, R L; Hickton, C M; Sizeland, P; Hannah, A; Bailey, R R

    Recurrent disseminated intravascular coagulation occurred in 3 women after ingestion of quinine tablets for cramp. All had circulating quinine-dependent antibodies to platelets and in 2 there was initial evidence of antibody consumption, with low titres that rose steeply over the next few days and remained high for many months.

  20. Intravascular volume after aneurysmal subarachnoid hemorrhage

    NARCIS (Netherlands)

    Hoff, R.G.

    2009-01-01

    Intravascular volume after aneurysmal subarachnoid hemorrhage A subarachnoid hemorrhage (SAH) from a ruptured cerebral aneurysm is a devastating disorder with an often poor prognosis. The occurrence of delayed cerebral ischemia (DCI) is one of the most important factors determining outcome in

  1. Disseminated Intravascular Coagulation Following Induction of ...

    African Journals Online (AJOL)

    Background: Disseminated Intravascular coagulopathy (DIC) has been reported following use of Misoprostol which is an old drug with new indications in Obstetrics and. Gynecology. Its effectiveness, low cost, stability in tropical conditions and ease of administration as well as side effects like gastrointestinal effect, uterine ...

  2. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Directory of Open Access Journals (Sweden)

    Kensuke Tashiro, MD

    2017-11-01

    Conclusions:. Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery.

  3. Theoretical model of intravascular paramagnetic tracers effect on tissue relaxation

    DEFF Research Database (Denmark)

    Kjølby, Birgitte Fuglsang; Østergaard, Leif; Kiselev, Valerij G

    2006-01-01

    The concentration of MRI tracers cannot be measured directly by MRI and is commonly evaluated indirectly using their relaxation effect. This study develops a comprehensive theoretical model to describe the transverse relaxation in perfused tissue caused by intravascular tracers. The model takes...... into account a number of individual compartments. The signal dephasing is simulated in a semianalytical way by embedding Monte Carlo simulations in the framework of analytical theory. This approach yields a tool for fast, realistic simulation of the change in the transverse relaxation. The results indicate...... with bulk blood. The enhancement of relaxation in tissue is due to the contrast in magnetic susceptibility between blood vessels and parenchyma induced by the presence of paramagnetic tracer. Beyond the perfusion measurements, the results can be applied to quantitation of functional MRI and to vessel size...

  4. Mapping intravascular ultrasound controversies in interventional cardiology practice.

    Directory of Open Access Journals (Sweden)

    David Maresca

    Full Text Available Intravascular ultrasound is a catheter-based imaging modality that was developed to investigate the condition of coronary arteries and assess the vulnerability of coronary atherosclerotic plaques in particular. Since its introduction in the clinic 20 years ago, use of intravascular ultrasound innovation has been relatively limited. Intravascular ultrasound remains a niche technology; its clinical practice did not vastly expand, except in Japan, where intravascular ultrasound is an appraised tool for guiding percutaneous coronary interventions. In this qualitative research study, we follow scholarship on the sociology of innovation in exploring both the current adoption practices and perspectives on the future of intravascular ultrasound. We conducted a survey of biomedical experts with experience in the technology, the practice, and the commercialization of intravascular ultrasound. The collected information enabled us to map intravascular ultrasound controversies as well as to outline the dynamics of the international network of experts that generates intravascular ultrasound innovations and uses intravascular ultrasound technologies. While the technology is praised for its capacity to measure coronary atherosclerotic plaque morphology and is steadily used in clinical research, the lack of demonstrated benefits of intravascular ultrasound guided coronary interventions emerges as the strongest factor that prevents its expansion. Furthermore, most of the controversies identified were external to intravascular ultrasound technology itself, meaning that decision making at the industrial, financial and regulatory levels are likely to determine the future of intravascular ultrasound. In light of opinions from the responding experts', a wider adoption of intravascular ultrasound as a stand-alone imaging modality seems rather uncertain, but the appeal for this technology may be renewed by improving image quality and through combination with

  5. Techniques for Intravascular Foreign Body Retrieval

    International Nuclear Information System (INIS)

    Woodhouse, Joe B.; Uberoi, Raman

    2013-01-01

    As endovascular therapies increase in frequency, the incidence of lost or embolized foreign bodies is increasing. The presence of an intravascular foreign body (IFB) is well recognized to have the potential to cause serious complications. IFB can embolize and impact critical sites such as the heart, with subsequent significant morbidity or mortality. Intravascular foreign bodies most commonly result from embolized central line fragments, but they can originate from many sources, both iatrogenic and noniatrogenic. The percutaneous approach in removing an IFB is widely perceived as the best way to retrieve endovascular foreign bodies. This minimally invasive approach has a high success rate with a low associated morbidity, and it avoids the complications related to open surgical approaches. We examined the characteristics, causes, and incidence of endovascular embolizations and reviewed the various described techniques that have been used to facilitate subsequent explantation of such materials

  6. Intravascular photoacoustic imaging of human coronary atherosclerosis

    Science.gov (United States)

    Jansen, Krista; van der Steen, Antonius F. W.; Springeling, Geert; van Beusekom, Heleen M. M.; Oosterhuis, J. Wolter; van Soest, Gijs

    2011-03-01

    We demonstrate intravascular photoacoustic imaging of human coronary atherosclerotic plaque. We specifically imaged lipid content, a key factor in vulnerable plaques that may lead to myocardial infarction. An integrated intravascular photoacoustics (IVPA) and ultrasound (IVUS) catheter with an outer diameter of 1.25 mm was developed. The catheter comprises an angle-polished optical fiber adjacent to a 30 MHz single-element transducer. The ultrasonic transducer was optically isolated to eliminate artifacts in the PA image. We performed measurements on a cylindrical vessel phantom and isolated point targets to demonstrate its imaging performance. Axial and lateral point spread function widths were 110 μm and 550 μm, respectively, for PA and 89 μm and 420 μm for US. We imaged two fresh human coronary arteries, showing different stages of disease, ex vivo. Specific photoacoustic imaging of lipid content, is achieved by spectroscopic imaging at different wavelengths between 1180 and 1230 nm.

  7. Heterogeneous Intravascular Ultrasound Findings of Stent Thrombosis

    OpenAIRE

    Morofuji, Toru; Inaba, Shinji; Aisu, Hiroe; Takahashi, Kayo; Saito, Makoto; Higashi, Haruhiko; Yoshii, Toyofumi; Sumimoto, Takumi

    2017-01-01

    Objective The underlying mechanisms of stent thrombosis are not completely understood. Methods We experienced 12 definite stent thrombosis cases (1 early, 1 late, and 10 very late) at our hospital from July 2011 to April 2016 and evaluated the possible causes of stent thrombosis by intravascular ultrasound (IVUS). Results Five different potential morphological causes of stent thrombosis (neoatherosclerosis, stent malapposition, stent fracture, edge dissection, and stent underexpansion) were d...

  8. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Science.gov (United States)

    Yamashita, Shuji; Narushima, Mitsunaga; Koshima, Isao; Miyamoto, Shimpei

    2017-01-01

    Background: Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined its usefulness. Methods: Between January 2013 and February 2015, 11 anastomoses in 11 cases of lymphaticovenular anastomosis for lymphedema patients, 14 anastomoses in 7 cases of free perforator flap transfer with supermicrosurgical perforator-to-perforator anastomosis, and 9 anastomoses in 5 cases of fingertip replantation were performed using hemi-IVaS. Time required for anastomosis and complications were examined. Flap survival rate was also examined in free perforator flap transfer cases and fingertip replantation cases. Results: In all cases, anastomoses were performed without complications such as inadvertent catching of the back wall of the vessel during the procedure or the need for reanastomoses. The average time required to complete the anastomosis was 16.4 ± 3.20 minutes using the hemi IVaS technique. All flaps survived in the supermicrosurgical perforator-to-perforator anastomosis as well as fingertip replantation cases. Conclusions: Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery. PMID:29263952

  9. Intravascular imaging with a storage phosphor detector

    Energy Technology Data Exchange (ETDEWEB)

    Shikhaliev, Polad M; Petrek, Peter; Matthews, Kenneth L II; Fritz, Shannon G [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA (United States); Bujenovic, L Steven [PET Imaging Center, Our Lady of the Lake Medical Center, Baton Rouge, LA (United States); Xu Tong, E-mail: pshikhal@lsu.ed [Department of Physics, Carleton University, Ottawa (Canada)

    2010-05-21

    The aim of this study is to develop and test an intravascular positron imaging system based on a storage phosphor detector for imaging and detecting vulnerable plaques of human coronary arteries. The radiotracer F18-FDG accumulates in vulnerable plaques with inflammation of the overlying cap. The vulnerable plaques can, therefore, be imaged by recording positrons emitted from F18-FDG with a detector inserted into the artery. A prototype intravascular detector was constructed based on storage phosphor. The detector uses a flexible storage phosphor tube with 55 mm length, 2 mm diameter and 0.28 mm wall thickness. The intravascular detector is guided into the vessel using x-ray fluoroscopy and the accumulated x-ray signal must be erased prior to positron imaging. For this purpose, a light diffuser, 0.9 mm in diameter and 55 mm in length, was inserted into the detector tube. The light diffuser was connected to a laser source through a 2 m long optical fiber. The diffuser redirected the 0.38 W laser light to the inner surface of the phosphor detector to erase it. A heart phantom with 300 cm{sup 3} volume and three coronary arteries with 3.2 mm diameter and with several plaques was constructed. FDG solution with 0.5 {mu}Ci cm{sup -3} activity concentration was filled in the heart and coronary arteries. The detector was inserted in a coronary artery and the signal from the plaques and surrounding background activity was recorded for 2 min. Then the phosphor detector was extracted and read out using a storage phosphor reader. The light diffuser erased the signal resulting from fluoroscopic exposure to level below that encountered during positron imaging. Vulnerable plaques with area activities higher than 1.2 nCi mm{sup -2} were visualized by the detector. This activity is a factor of 10-20 lower than that expected in human vulnerable plaques. The detector was able to image the internal surface of the coronary vessels with 50 mm length and 360{sup 0} circumference. Spatial

  10. Mapping Intravascular Ultrasound Controversies in Interventional Cardiology Practice

    NARCIS (Netherlands)

    Maresca, D.; Adams, S.; Maresca, B.; Van der Steen, A.F.W.

    2014-01-01

    Intravascular ultrasound is a catheter-based imaging modality that was developed to investigate the condition of coronary arteries and assess the vulnerability of coronary atherosclerotic plaques in particular. Since its introduction in the clinic 20 years ago, use of intravascular ultrasound

  11. Pathologic contrast enhancement of cerebral lesions: A comparative study using stereotactic CT, stereotactic MR imaging, and stereotactic biopsy

    International Nuclear Information System (INIS)

    Earnest, F. IV; Kelly, P.J.; Scheithauer, B.; Kall, B.; Cascino, T.L.; Ehman, R.L.; Forbes, G.

    1986-01-01

    The author compared the pattern and degree of Gd-DTPA dimeglumine contrast enhancement demonstrated on stereotactic MR images with that seen on stereotactic CT images obtained after conventional iodinated contrast agent enhancement and with histopathologic findings on sequential stereotactic brain biopsies. Stereotactic biopsies of the areas that enhanced on CT or MR imaging revealed tumor tissue with neovascularity. Tumor tissue with no or mild neovascularity did not enhance with contrast agent administration. Isolated tumor cells were frequently found beyond the margins of some primary brain neoplasms defined by contrast agent-enhanced MR imaging and CT. The histopathologic findings associated with pathologic contrast agent enhancement are presented

  12. Ventricular metastasis resulting in disseminated intravascular coagulation

    Directory of Open Access Journals (Sweden)

    Davis Ian D

    2005-05-01

    Full Text Available Abstract Background Disseminated Intravascular Coagulation (DIC complicates up to 7% of malignancies, the commonest solid organ association being adenocarcinoma. Transitional Cell Carcinoma (TCC has rarely been associated with DIC. Case presentation A 74-year-old woman with TCC bladder and DIC was found to have a cardiac lesion suspicious for metastatic disease. The DIC improved with infusion of plasma and administration of Vitamin K, however the cardiac lesion was deemed inoperable and chemotherapy inappropriate; given the patients functional status. We postulate that direct activation of the coagulation cascade by the intraventricular metastasis probably triggered the coagulopathy in this patient. Conclusion Cardiac metastases should be considered in cancer patients with otherwise unexplained DIC. This may influence treatment choices.

  13. Guidelines for the diagnosis and management of disseminated intravascular coagulation

    NARCIS (Netherlands)

    Levi, M. [=Marcel M.; Toh, C. H.; Thachil, J.; Watson, H. G.

    2009-01-01

    The diagnosis of disseminated intravascular coagulation (DIC) should encompass both clinical and laboratory information. The International Society for Thrombosis and Haemostasis (ISTH) DIC scoring system provides objective measurement of DIC. Where DIC is present the scoring system correlates with

  14. Disseminated intravascular and intracardiac thrombosis after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Deepak K Tempe

    2017-01-01

    Full Text Available Massive intracardiac and intravascular thrombosis is a rare complication following cardiopulmonary bypass (CPB. Most of the cases of the disseminated thrombosis have been reported in patients undergoing complex cardiac surgeries and those receiving antifibrinolytic agents during CPB. We report the occurrence of disseminated intravascular and intracardiac thrombosis after CPB in a patient undergoing mitral valve replacement in which no antifibrinolytic agent was used. The possible pathophysiology and management of the patient is discussed.

  15. Intravascular Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Maria S. Khan MD, FACP

    2014-03-01

    Full Text Available Case Presentation . A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH 1231 IU/L. Except for a positive DNA test for Epstein–Barr virus (EBV infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion . Intravascular large cell B-cell lymphoma (IVLBCL is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH

  16. Iodinated contrast media alter immune responses in pro-inflammatory states.

    LENUS (Irish Health Repository)

    O'Donnell, David H

    2010-07-01

    Hypertonic saline causes a transient elevation of blood osmolality and has been shown to alter cellular inflammatory responses in pro-inflammatory states. Intravascular administration of iodine contrast media also causes a transient elevation of blood osmolarity.

  17. A quality management program in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Chakri, Abderrahim; Thomadsen, Bruce

    2002-01-01

    While simple, intravascular brachytherapy (IVB) presents a considerable potential for harm to the patient. The medical physicist maintains the responsibility to minimize the likelihood of operational problems or dosimetric errors. The principals for safe operation remain the same as with any radiotherapy treatment: to deliver the correct dose, to the correct location, safety. To develop an effective and comprehensive quality management (QM) program for IVB, a physicist should utilize proven risk assessment techniques rather than simply thinking of things to check, and follow guidances such as ISO9001:2000. The proposed QM program includes the following: Procedures designed to assure the safety of the patient: Identification of the patient; tests of the integrity and patency for the delivery catheter, operation of the source train, and patency of the catheter in the treatment position; a check for recovery preparations; and verification of source recovery. Procedures to assure positional accuracy of the treatment: Verification of the positioning the catheter in the artery and of the sources in the catheter. Procedures to assure dosimetry accuracy: Acceptance testing of the device, including verification of the source strength and uniformity, and of the treatment duration tables; verification of the treatment prescription and duration for each patient; and control measures that minimize the likelihood of errors removing the source at the correct time

  18. Disseminated intravascular coagulation in solid tumors

    International Nuclear Information System (INIS)

    Terzieff, V.; Alonso, I.; Vázquez, A.

    2004-01-01

    It is estimated that 20-25% of cases of disseminated intravascular coagulation (DIC) relate to an underlying neoplasia primarily hematologic. It is estimated that about 5% of patients with solid tumors have CID clinic, although the incidence of subclinical alterations is much higher. The CID is not limited to the activation of the coagulation cascade, which leads to bleeding micro thrombosis and consumption of coagulation factors. Solid tumors are frequently associated adenocarcinomas producers mucin (especially gastric), usually in the context of a disseminated disease. The mucin may act as a promoter of the cascade, but probably it is a multi-event. High levels of TNF to produced by the tumor mass and chemotherapy-induced cell lysis have Also linked. Although the bleeding is usually oriented diagnosis, the most frequent cause of death is thrombosis. There are no specific tests for diagnosis. Elevated levels of D-dimer and products oriented fibrinogen degradation diagnosis. No reduction fibrinogen and almost always, one thrombocytopenia consumption. Treatment is complex and there is no consensus on many points. To recover the lost factors for consumption, it is recommended to use fresh frozen plasma and / or washed red blood cells. the heparin anticoagulation low dose is indicated since the disease causal can not be controlled quickly, but should not be initiated if there thrombocytopenia 50.000.El under profuse bleeding can require the use of tranexamic acid or EACA. Acute DIC, the case of our patient, is rare and very serious

  19. Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications

    Science.gov (United States)

    Ma, Dinglong; Bec, Julien; Yankelevich, Diego R.; Gorpas, Dimitris; Fatakdawala, Hussain; Marcu, Laura

    2014-01-01

    Abstract. We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures. PMID:24898604

  20. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    still the first line of defense. However, with the fidelity of 64-slice CT imaging, this technique has recently become an option when the patient presents with symptoms of reduced arterial flow. Single photon emission computerized tomography (SPECT) treadmill exercise testing is a standard non-invasive test for decreased perfusion of heart muscle, but is time consuming and not suited for emergent evaluation. Once the invasive clinical option of catherization is chosen, this provides the opportunity for intravascular ultrasound (IVUS) imaging. As the probe is pulled through the artery, the diameter at different parts is measurable, and monochrome contrast in the constricted area reveals the presence of tissue with a different ultrasonic response. Also, via an optical catheter with a fiber-optic conductor, the possibly of spectroscopic analysis of arterial walls is now a reality. In this case, the optical transducer is coupled to a near-infrared spectrometer. Revealing the arterial chemical health means that plaque vulnerability and imminent risk could be assessed by the physician. The classical emergency use of catherization involves a contrast agent and dynamic X-ray imaging to locate the constriction, determine its severity, and possibly perform angioplasty, and stent placement.

  1. Intravascular brachytherapy for peripheral vascular disease

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2008-09-01

    Full Text Available Scientific background: Percutaneous transluminal angioplasties (PTA through balloon dilatation with or without stenting, i.e. vessel expansion through balloons with or without of implantation of small tubes, called stents, are used in the treatment of peripheral artery occlusive disease (PAOD. The intravascular vessel irradiation, called intravascular brachytherapy, promises a reduction in the rate of repeated stenosis (rate of restenosis after PTA. Research questions: The evaluation addresses questions on medical efficacy, cost-effectiveness as well as ethic, social and legal implications in the use of brachytherapy in PAOD patients. Methods: A systematic literature search was conducted in August 2007 in the most important medical electronic databases for publications beginning from 2002. The medical evaluation included randomized controlled trials (RCT. The information synthesis was performed using meta-analysis. Health economic modeling was performed with clinical assumptions derived from the meta-analysis and economical assumptions derived from the German Diagnosis Related Groups (G-DRG-2007. Results: Medical evaluation: Twelve publications about seven RCT on brachytherapy vs. no brachytherapy were included in the medical evaluation. Two RCT showed a significant reduction in the rate of restenosis at six and/or twelve months for brachytherapy vs. no brachytherapy after successful balloon dilatation, the relative risk in the meta-analysis was 0.62 (95% CI: 0.46 to 0.84. At five years, time to recurrence of restenosis was significantly delayed after brachytherapy. One RCT showed a significant reduction in the rate of restenosis at six months for brachytherapy vs. no brachytherapy after PTA with optional stenting, the relative risk in the meta-analysis was 0.76 (95% CI: 0.61 to 0.95. One RCT observed a significantly higher rate of late thrombotic occlusions after brachytherapy in the subgroup of stented patients. A single RCT for brachytherapy

  2. Fulminant intravascular lymphomatosis mimicking acute haemorrhagic leukoencephalopathy.

    Science.gov (United States)

    Marino, D; Sicurelli, F; Cerase, A; Tripodi, S; Cintorino, M; Lazzi, S; Federico, A

    2012-09-15

    Intravascular lymphomatosis (IVL) is a rare non-Hodgkin's lymphoma, usually of B cell lineage, characterized by massive angiotropic growth. The clinical presentation of IVL may include changes in mental status, non-localizing neurological deficits, seizures, fever of unknown origin and skin changes. Because of its rarity and the absence of specific diagnostic procedures except for cerebral biopsy, diagnosis is often postmortem. Brain MRI usually shows non-specific abnormalities. The purpose of this case report is to increase the knowledge of clinical and neuroimaging features of IVL by describing the findings observed in a 71-year-old patient. A 71-year-old male was admitted for right hemiparesis, acute cognitive impairment and febricula. A bone marrow biopsy resulted normal. He then developed a rapid progressive impairment of his mental status and left hemisoma motor seizures. Brain CT and MRI were interpreted as consistent with acute haemorrhagic leukoencephalopathy (AHLE), including multiple areas of restricted diffusion without gadolinium enhancement and a small focal area of gadolinium enhancement in the left temporal lobe white matter. The patient died within a few days and the autopsy led to the diagnosis of IVL. IVL may present with a variety of clinical signs and symptoms, including stroke and hemiparesis. IVL may mimic AHLE at brain MRI. However, the evidence of multiple areas of restricted diffusion without gadolinium enhancement and of a small area of gadolinium enhancement could have led to the correct diagnosis. IVL should be added to the differential diagnosis of AHLE at brain MRI. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Therapeutic intervention in disseminated intravascular coagulation: have we made any progress in the last millennium?

    NARCIS (Netherlands)

    Levi, Marcel; de Jonge, Evert; van der Poll, Tom

    2002-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to widespread deposition of fibrin in the circulation. Recent knowledge on important pathogenetic mechanisms that may lead to DIC has resulted in novel preventive and

  4. Emergency treatment by intravascular embolization in traumatic carotid cavernous fistula

    International Nuclear Information System (INIS)

    Tang Jun; Sun Zengtao; Liu Zuoqin; Liu Yanjun; Li Fengxin

    2006-01-01

    Objective: To discuss the method of intervenfional intravascular treatment in traumatic carotid cavernous fistula (TCCF) and the significance of clinical application in emergency. Methods: In 297 eases of TCCF, 36 cases were treated by interventional intravascular embolization by detachable balloon, embolization orificium or occlusion in one side of carotid artery. In the 36 cases, serious epistaxis occurred in 22 eases, cortical vein inflow in 9 cases, intracranial hemorrhage in 3 cases, aggravation of eyesight in 3 cases, and limb dysfunction in 2 cases. Results: Fistula was successfully embolized and internal carotid artery remained patent in 19 cases. Complete embolization of orificium or internal carotid artery was achieved in 17 eases. The serious epistaxias in 22 cases and intracranial hemorrhage in 3 cases stopped. Eyesight recovered in 2 eases and improved in 1 case. Limb dysfunction improved evidently in 2 cases. Conclusion: Intravascular embolization treatment is the first therapeutic choice for TCCF, especially in emergency. It is necessary, safe and effective. (authors)

  5. Intravascular ultrasonic-photoacoustic (IVUP) endoscope with 2.2-mm diameter catheter for medical imaging.

    Science.gov (United States)

    Bui, Nhat Quang; Hlaing, Kyu Kyu; Nguyen, Van Phuc; Nguyen, Trung Hau; Oh, Yun-Ok; Fan, Xiao Feng; Lee, Yong Wook; Nam, Seung Yun; Kang, Hyun Wook; Oh, Junghwan

    2015-10-01

    Intravascular ultrasound (IVUS) imaging is extremely important for detection and characterization of high-risk atherosclerotic plaques as well as gastrointestinal diseases. Recently, intravascular photoacoustic (IVPA) imaging has been used to differentiate the composition of biological tissues with high optical contrast and ultrasonic resolution. The combination of these imaging techniques could provide morphological information and molecular screening to characterize abnormal tissues, which would help physicians to ensure vital therapeutic value and prognostic significance for patients before commencing therapy. In this study, integration of a high-frequency IVUS imaging catheter (45MHz, single-element, unfocused, 0.7mm in diameter) with a multi-mode optical fiber (0.6mm in core diameter, 0.22 NA), an integrated intravascular ultrasonic-photoacoustic (IVUP) imaging catheter, was developed to provide spatial and functional information on light distribution in a turbid sample. Simultaneously, IVUS imaging was co-registered to IVPA imaging to construct 3D volumetric sample images. In a phantom study, a polyvinyl alcohol (PVA) tissue-mimicking arterial vessel phantom with indocyanine green (ICG) and methylene blue (MB) inclusion was used to demonstrate the feasibility of mapping the biological dyes, which are used in cardiovascular and cancer diagnostics. For the ex vivo study, an excised sample of pig intestine with ICG was utilized to target the biomarkers present in the gastrointestinal tumors or the atherosclerotic plaques with the proposed hybrid technique. The results indicated that IVUP endoscope with the 2.2-mm diameter catheter could be a useful tool for medical imaging. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Contrast-enhanced peripheral MRA

    DEFF Research Database (Denmark)

    Nielsen, Yousef W; Thomsen, Henrik S

    2012-01-01

    MRI contrast agent is injected intravenously and T1-weighted images are acquired in the subsequent arterial first-pass phase. In order to achieve high quality MR angiograms without interfering venous contamination or artifacts, a number of factors need to be taken into account. This includes magnetic......-state MRA. Gadolinium(Gd)-based contrast agents are used for CE-MRA of the peripheral arteries. Extracellular Gd agents have a pharmacokinetic profile similar to iodinated contrast media. Accordingly, these agents are employed for first-pass MRA. Blood-pool Gd-based agents are characterized by prolonged...... intravascular stay, due to macromolecular structure or protein binding. These agents can be used for first-pass, as well as steady-state MRA. Some Gd-based contrast agents with low thermodynamic stability have been linked to development of nephrogenic systemic fibrosis in patients with severe renal...

  7. Intravascular Young's modulus reconstruction using a parametric finite element model

    NARCIS (Netherlands)

    Baldewsing, R.A.; Oomens, C.W.J.; Steen, van der A.F.W.; Yuhas, D.; Schneider, S.C.

    2003-01-01

    IntraVascular UltraSound (IVUS) elastography may be used to detect vulnerable, rupture prone plaques, which are held responsible for the majority of acute coronary syndromes. IVUS elastography accomplishes this by visualising local incremental radial strain of arteries, in so-called elastograms.

  8. 21 CFR 880.5440 - Intravascular administration set.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intravascular administration set. 880.5440 Section 880.5440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use...

  9. Heartbeat OCT: In vivo intravascular megahertz-optical coherence tomography

    NARCIS (Netherlands)

    T. Wang (Tianshi); A.F.H. Pfeiffer (Andreas); E.S. Regar (Eveline); W. Wieser (Wolfgang); H.M.M. van Beusekom (Heleen); C.T. Lancée (Charles); T. Springeling (Tirza); I. Krabbendam (Ilona); A.F.W. van der Steen (Ton); R. Huber (Roman); G. van Soest (Gijs)

    2015-01-01

    textabstractCardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging

  10. Mechanical scanning in intravascular ultrasound imaging: Artifacts and driving mechanisms

    NARCIS (Netherlands)

    H. ten Hoff (H.); E.J. Gussenhoven (Elma); C.M. Korbijn (Carin); F. Mastik (Frits); C.T. Lancée (Charles); N. Bom (Klaas)

    1995-01-01

    textabstractObjective: Currently, intravascular ultrasound (US) imaging catheters are developed and produced to provide a complementary diagnostic method in the treatment of blood vessel obstructive disease. Typical catheter dimensions are a diameter of 1–2.5 mm and a length of 1–1.5 m. A real-time

  11. Intravascular catheter related infections in children admitted on the ...

    African Journals Online (AJOL)

    peripheral venous intravascular catheters uncoated with no antibiotic or antiseptic, was done. Social demographic characteristics, anthropometry, clinical examination including the catheter site were determined at enrollment. The children had their blood, catheter tip and hub samples taken off for culture and sensitivity as ...

  12. Disseminated intravascular coagulation in meningococcal sepsis. Case 7

    NARCIS (Netherlands)

    Zeerleder, S.; Zürcher Zenklusen, R.; Hack, C. E.; Wuillemin, W. A.

    2003-01-01

    We report on a man (age: 49 years), who died from severe meningococcal sepsis with disseminated intravascular coagulation (DIC), multiple organ dysfunction syndrome and extended skin necrosis. We discuss in detail the pathophysiology of the activation of coagulation and fibrinolysis during sepsis.

  13. Intravascular catheter sepsis | Mer | South African Medical Journal

    African Journals Online (AJOL)

    Intravascular devices are an integral component of modern-day medical practice. They are used to administer intravenous fluids, medications, blood products and parenteral nutrition. In addition, they serve as a valuable monitor of the haemodynamic status of critically ill patients.

  14. Intravascular forward-looking ultrasound transducers for microbubble-mediated sonothrombolysis.

    Science.gov (United States)

    Kim, Jinwook; Lindsey, Brooks D; Chang, Wei-Yi; Dai, Xuming; Stavas, Joseph M; Dayton, Paul A; Jiang, Xiaoning

    2017-06-14

    Effective removal or dissolution of large blood clots remains a challenge in clinical treatment of acute thrombo-occlusive diseases. Here we report the development of an intravascular microbubble-mediated sonothrombolysis device for improving thrombolytic rate and thus minimizing the required dose of thrombolytic drugs. We hypothesize that a sub-megahertz, forward-looking ultrasound transducer with an integrated microbubble injection tube is more advantageous for efficient thrombolysis by enhancing cavitation-induced microstreaming than the conventional high-frequency, side-looking, catheter-mounted transducers. We developed custom miniaturized transducers and demonstrated that these transducers are able to generate sufficient pressure to induce cavitation of lipid-shelled microbubble contrast agents. Our technology demonstrates a thrombolysis rate of 0.7 ± 0.15 percent mass loss/min in vitro without any use of thrombolytic drugs.

  15. Neuroendocrine and renal effects of intravascular volume expansion in compensated heart failure

    DEFF Research Database (Denmark)

    Gabrielsen, A; Bie, P; Holstein-Rathlou, N H

    2001-01-01

    To examine if the neuroendocrine link between volume sensing and renal function is preserved in compensated chronic heart failure [HF, ejection fraction 0.29 +/- 0.03 (mean +/- SE)] we tested the hypothesis that intravascular and central blood volume expansion by 3 h of water immersion (WI) elicits...... sustained angiotensin-converting enzyme inhibitor therapy, n = 9) absolute and fractional sodium excretion increased (P Renal free water clearance increased during WI in control subjects but not in HF......, albeit plasma vasopressin concentrations were similar in the two groups. In conclusion, the neuroendocrine link between volume sensing and renal sodium excretion is preserved in compensated HF. The natriuresis of WI is, however, modulated by the prevailing ANG II and Aldo concentrations. In contrast...

  16. Newer techniques for intravascular and intraoperative neurointerventional procedures

    International Nuclear Information System (INIS)

    Higashida, R.T.; Halbach, V.V.; Hieshima, G.B.; Yang, P.

    1987-01-01

    A videotape demonstrating newer techniques used in intravascular and intraoperative embolization procedures will be presented. The authors discuss the use of some of the newer embolic agents, real-time digital subtraction angiography, roadmapping techniques, and the use of microcatheters and steerable micro guide wires, which has greatly facilitated neurovascullar embolization procedures and enhanced patient safety. A number of actual intraoperative and intravascular cases will be shown demonstrating treatment of vascular malformations of the brain and spinal cord, carotid cavernous sinus fistulas, aneurysms and dural arteriovenous malformations. The indications for treatment, patient selection, technical preparation and newer methodologies and approaches to complex vascular lesions of the brain and spinal cord are discussed in detail

  17. Intravascular brachytherapy: a model for the calculation of the dose

    International Nuclear Information System (INIS)

    Pirchio, Rosana; Martin, Gabriela; Rivera, Elena; Cricco, Graciela; Cocca, Claudia; Gutierrez, Alicia; Nunez, Mariel; Bergoc, Rosa; Guzman, Luis; Belardi, Diego

    2002-01-01

    In this study we present the radiation dose distribution for a theoretical model with Montecarlo simulation, and based on an experimental model developed for the study of the prevention of restenosis post-angioplasty employing intravascular brachytherapy. In the experimental in vivo model, the atherosclerotic plaques were induced in femoral arteries of male New Zealand rabbits through surgical intervention and later administration of cholesterol enriched diet. For the intravascular irradiation we employed a 32P source contained within the balloon used for the angioplasty. The radiation dose distributions were calculated using the Monte Carlo code MCNP4B according to a segment of a simulated artery. We studied the radiation dose distribution in the axial and radial directions for different thickness of the atherosclerotic plaques. The results will be correlated with the biologic effects observed by means of histological analysis of the irradiated arteries (Au)

  18. Design of low noise transimpedance amplifier for intravascular ultrasound

    KAUST Repository

    Reda, Dina

    2009-11-01

    In this paper, we study transimpedance amplifiers for capacitive sensing applications with a focus on Intravascular Ultra Sound (IVUS). We employ RF noise cancellation technique on capacitive feedback based transimpedance amplifiers. This technique eliminates the input-referred noise of TIAs completely and enhances the dynamic range of front-end electronics. Simulation results verify the proposed technique used in two different TIA topologies employing shunt-shunt feedback. ©2009 IEEE.

  19. Asian-variant intravascular lymphoma in the African race

    Directory of Open Access Journals (Sweden)

    Holly Geyer

    2012-03-01

    Full Text Available Intravascular large B-cell lymphoma (IVLBCL is an exceptionally rare form of non- Hodgkin lymphoma (NHL distinguished by the preferential growth of neoplastic cells within blood vessel lumen. Challenging to detect and deemed disseminated at diagnosis, this condition is characterized by a highly aggressive, inconspicuous course with a high mortality rate. We describe the case of a 48 year-old African-American female presenting with a two month history of low-grade fevers and malaise. Laboratory data was notable for anemia, thrombocytopenia, elevated liver function tests, and hematuria. An extensive workup for infectious, rheumatologic and malignant causes was negative. Her symptoms progressed and within two weeks, she was admitted for disseminated intravascular coagulation (DIC. Her course was complicated by diffuse pulmonary hemorrhage and ultimately, care was withdrawn. Autopsy identified widespread CD-20 positive intravascular large B-cell lymphoma with significant hepatosplenic involvement, characteristic of the Asian variant IVLBCL. This case uniquely highlights development of the Asian variant IVLBVL in a previously undescribed race. Identified by its intraluminal vascular growth pattern, IVLBCL generally spares lymphatic channels. Diagnosis and differentiation of this condition from other hematological malignancies via skin, visceral and bone marrow biopsy is imperative as anthracycline-containing chemotherapies may significantly improve clinical outcomes. This article outlines the common presentation, natural course, and treatment options of IVLBCL, along with the histopathology, immunohistochemistry, and chromosomal aberrations common to this condition.

  20. Renal denervation by intravascular ultrasound: Preliminary in vivo study

    Science.gov (United States)

    Sinelnikov, Yegor; McClain, Steve; Zou, Yong; Smith, David; Warnking, Reinhard

    2012-10-01

    Ultrasound denervation has recently become a subject of intense research in connection with the treatment of complex medical conditions including neurological conditions, development of pain management, reproduction of skin sensation, neuropathic pain and spasticity. The objective of this study is to investigate the use of intravascular ultrasound to produce nerve damage in renal sympathetic nerves without significant injury to the renal artery. This technique may potentially be used to treat various medical conditions, such as hypertension. The study was approved by the Institutional Animal Care and Use Committee. Ultrasound was applied to renal nerves of the swine model for histopathological evaluation. Therapeutic ultrasound energy was delivered circumferentially by an intravascular catheter maneuvered into the renal arteries. Fluoroscopic imaging was conducted pre-and post-ultrasound treatment. Animals were recovered and euthanized up to 30 hours post procedure, followed by necropsy and tissue sample collection. Histopathological examination showed evidence of extensive damage to renal nerves, characterized by nuclear pyknosis, hyalinization of stroma and multifocal hemorrhages, with little or no damage to renal arteries. This study demonstrates the feasibility of intravascular ultrasound as a minimally invasive renal denervation technique. Further studies are necessary to evaluate the long-term safety and efficacy of this technique and its related clinical significance.

  1. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound.

    Science.gov (United States)

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  2. Dynamic contrast enhanced ultrasound for therapy monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, John M. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Williams, Ross [Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Tremblay-Darveau, Charles; Sheeran, Paul S. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Milot, Laurent [Department of Medical Imaging, University of Toronto, Toronto, ON (Canada); Bjarnason, Georg A. [Department of Medical Oncology, University of Toronto, and Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); Burns, Peter N., E-mail: burns@sri.utoronto.ca [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Department of Medical Imaging, University of Toronto, Toronto, ON (Canada)

    2015-09-15

    Quantitative imaging is a crucial component of the assessment of therapies that target the vasculature of angiogenic or inflamed tissue. Dynamic contrast-enhanced ultrasound (DCE-US) using microbubble contrast offers the advantages of being sensitive to perfusion, non-invasive, cost effective and well suited to repeated use at the bedside. Uniquely, it employs an agent that is truly intravascular. This papers reviews the principles and methodology of DCE-US, especially as applied to anti-angiogenic cancer therapies. Reproducibility is an important attribute of such a monitoring method: results are discussed. More recent technical advances in parametric and 3D DCE-US imaging are also summarised and illustrated.

  3. Advances in equine computed tomography and use of contrast media.

    Science.gov (United States)

    Puchalski, Sarah M

    2012-12-01

    Advances in equine computed tomography have been made as a result of improvements in software and hardware and an increasing body of knowledge. Contrast media can be administered intravascularly or intrathecally. Contrast media is useful to differentiate between tissues of similar density. Equine computed tomography can be used for many different clinical conditions, including lameness diagnosis, fracture identification and characterization, preoperative planning, and characterization of skull diseases. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Silver nanoparticles as optical clearing agent enhancers to improve caries diagnostic by optical coherence tomography

    Science.gov (United States)

    Carneiro, Vanda S. M.; Mota, Cláudia C. B. O.; Souza, Alex F.; da Silva, Evair J.; da Silva, Andrea F.; Gerbi, Marleny E. M. M.; Gomes, Anderson S. L.

    2018-02-01

    The use of silver nanoparticles as optical clearing agent (OCA) enhancers to improve caries diagnostic by optical coherence tomography (OCT) is demonstrated here. Five molars with no evident cavitation were selected. The OCAs were based on aqueous solution of silver nanoparticles (AgNP, 1.18x 1014 particles/mL, ø ≈ 10nm) and its dilution at 10% in glycerol. Teeth were placed on a platform with a micrometric screw, and after applying the OCAs, they were scanned with a Callisto SD-OCT system operating ate 930nm central wavelength. The occlusal surfaces were scanned by OCT, capturing crosssectional images with 8 mm transversal scanning, generating numerical matrices (2000x512). The OCT images had their transverse dimension preserved. AgNP-OCAs promoted image stretching due to the modification in the light optical path caused by AgNP-OCAs refractive indices close to that of the enamel. AgNP-OCAs evidenced the enamel birefringence and highlighted initial demineralization areas, that presented defined margins with higher contrast between sound and demineralized regions, with higher OCT signal intensity in those areas.

  5. Why Have So Many Intravascular Glucose Monitoring Devices Failed?

    Science.gov (United States)

    Smith, John L; Rice, Mark J

    2015-07-01

    Secondary to the inherent limitations of both point-of-care and central laboratory glucose technologies, continuous glucose measurement has recently enjoyed a high level of investment. Because of the perceived advantages by some of measuring in the intravascular space compared to the subcutaneous tissue, a number of technologies have been developed. In this review, we evaluate nine systems that have shown promise, although only one of these has been cleared for sale in the United States. The detection methodology, regulatory status, technical issues, and company circumstance surrounding each technology are examined. © 2015 Diabetes Technology Society.

  6. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K; Hørlyck, Arne; Østergaard, Kristine Hovkjær

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination....... All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure....... revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along...

  7. Thyroid storm complicated by bicytopenia and disseminated intravascular coagulation.

    Science.gov (United States)

    Tokushima, Yoshinori; Sakanishi, Yuta; Nagae, Kou; Tokushima, Midori; Tago, Masaki; Tomonaga, Motosuke; Yoshioka, Tsuneaki; Hyakutake, Masaki; Sugioka, Takashi; Yamashita, Shu-ichi

    2014-07-24

    Male, 23. Thyroid storm. Delirium • diarrhea • fever • hypertension • hyperventilation • tachycardia • weight loss. -. -. Endocrinology and Metabolic. Unusual clinical course. The clinical presentation of thyroid storm includes fever, tachycardia, hypertension, and neurological abnormalities. It is a serious condition with a high mortality rate. Furthermore, some other complications affect the clinical course of thyroid storm. Although it is reported that prognosis is poor when thyroid storm is complicated by disseminated intravascular coagulation syndrome (DIC) and leukopenia, reports of such cases are rare. A 23-year-old man presented with delirium, high pyrexia, diarrhea, and weight loss of 18 kg over 2 months. According to the criteria of Burch and Wartofsky, he was diagnosed with thyroid storm on the basis of his symptom-complex and laboratory data that confirmed the presence of hyperthyroidism. Investigations also found leukopenia, thrombocytopenia, and disseminated intravascular coagulation, all of which are very rare complications of thyroid storm. We successfully treated him with combined therapy including anti-thyroid medication, despite leukopenia. Early diagnosis and treatment are essential in ensuring a good outcome for patients with this rare combination of medical problems.

  8. High speed intravascular photoacoustic imaging of atherosclerotic arteries (Conference Presentation)

    Science.gov (United States)

    Piao, Zhonglie; Ma, Teng; Qu, Yueqiao; Li, Jiawen; Yu, Mingyue; He, Youmin; Shung, K. Kirk; Zhou, Qifa; Kim, Chang-Seok; Chen, Zhongping

    2016-02-01

    Cardiovascular disease is the leading cause of death in the industrialized nations. Accurate quantification of both the morphology and composition of lipid-rich vulnerable atherosclerotic plaque are essential for early detection and optimal treatment in clinics. In previous works, intravascular photoacoustic (IVPA) imaging for detection of lipid-rich plaque within coronary artery walls has been demonstrated in ex vivo, but the imaging speed is still limited. In order to increase the imaging speed, a high repetition rate laser is needed. In this work, we present a high speed integrated IVPA/US imaging system with a 500 Hz optical parametric oscillator laser at 1725 nm. A miniature catheter with 1.0 mm outer diameter was designed with a 200 μm multimode fiber and an ultrasound transducer with 45 MHz center frequency. The fiber was polished at 38 degree and enclosed in a glass capillary for total internal reflection. An optical/electrical rotary junction and pull-back mechanism was applied for rotating and linearly scanning the catheter to obtain three-dimensional imaging. Atherosclerotic rabbit abdominal aorta was imaged as two frame/second at 1725 nm. Furthermore, by wide tuning range of the laser wavelength from 1680 nm to 1770 nm, spectroscopic photoacoustic analysis of lipid-mimicking phantom and an human atherosclerotic artery was performed ex vivo. The results demonstrated that the developed IVPA/US imaging system is capable for high speed intravascular imaging for plaque detection.

  9. Intravascular stenting (IVaS) method for fingertip replantation.

    Science.gov (United States)

    Narushima, Mitsunaga; Mihara, Makoto; Koshima, Isao; Gonda, Koichi; Takuya, Iida; Kato, Harunosuke; Nakanishi, Kenji; Yamamoto, Yusuke; Araki, Jun; Abe, Hiroaki; Mundinger, Gerhard S; Kikuchi, Kazuki; Uehara, Eri

    2009-01-01

    Remarkable progress has been made in microsurgery. However, fingertip replantation following amputation has not gained much popularity because of its technical difficulty. We have developed the intravascular stenting (IVaS) method, in which a nylon monofilament is placed inside the vessel lumen to act as a temporary stent, facilitating anastomosis completion. This report describes 7 fingertip replantations using the IVaS method. Intravascular stent size varied from 4-0 to 6-0 (0.199-0.07 mm diameter). There were no cases in which the back wall of a vessel became inadvertently caught in the anastomosis. The overall survival rate for distal digital replants was 85% (6/7 replants). It is very difficult to evenly anastomose vessels of differing diameter, especially on a supermicrosurgical scale. In this respect, the IVaS method plays a role in stably anchoring the 2 vessel ends, allowing for the even spacing of suture knots, even in vessels of different caliber. Because of its ease of use and exactitude, many surgeons may be able to use the IVaS method to reliably complete small anastomoses in fingertip replantations.

  10. An Implantable Intravascular Pressure Sensor for a Ventricular Assist Device

    Directory of Open Access Journals (Sweden)

    Luigi Brancato

    2016-08-01

    Full Text Available The aim of this study is to investigate the intravascular application of a micro-electro-mechanical system (MEMS pressure sensor to directly measure the hemodynamic characteristics of a ventricular assist device (VAD. A bio- and hemo-compatible packaging strategy is implemented, based on a ceramic thick film process. A commercial sub-millimeter piezoresistive sensor is attached to an alumina substrate, and a double coating of polydimethylsiloxane (PDMS and parylene-C is applied. The final size of the packaged device is 2.6 mm by 3.6 mm by 1.8 mm. A prototype electronic circuit for conditioning and read-out of the pressure signal is developed, satisfying the VAD-specific requirements of low power consumption (less than 14.5 mW in continuous mode and small form factor. The packaged sensor has been submitted to extensive in vitro tests. The device displayed a temperature-independent sensitivity (12 μ V/V/mmHg and good in vitro stability when exposed to the continuous flow of saline solution (less than 0.05 mmHg/day drift after 50 h. During in vivo validation, the transducer has been successfully used to record the arterial pressure waveform of a female sheep. A small, intravascular sensor to continuously register the blood pressure at the inflow and the outflow of a VAD is developed and successfully validated in vivo.

  11. Th1 Differentiation Drives the Accumulation of Intravascular, Non-protective CD4 T Cells during Tuberculosis.

    Science.gov (United States)

    Sallin, Michelle A; Sakai, Shunsuke; Kauffman, Keith D; Young, Howard A; Zhu, Jinfang; Barber, Daniel L

    2017-03-28

    Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1-polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find that IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73 + CXCR3 + T-bet dim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL- 12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1 + KLRG1 + Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69 + CD103 + tissue resident phenotype effectors in lung. In contrast, Th1-cell-derived IFN-γ inhibits the accumulation of intravascular CX3CR1 + KLRG1 + Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis. Published by Elsevier Inc.

  12. Th1 Differentiation Drives the Accumulation of Intravascular, Non-protective CD4 T Cells during Tuberculosis

    Directory of Open Access Journals (Sweden)

    Michelle A. Sallin

    2017-03-01

    Full Text Available Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1-polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find that IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73+CXCR3+T-betdim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL- 12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1+KLRG1+ Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69+CD103+ tissue resident phenotype effectors in lung. In contrast, Th1-cell-derived IFN-γ inhibits the accumulation of intravascular CX3CR1+KLRG1+ Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis.

  13. Th1 differentiation drives the accumulation of intravascular, non-protective CD4 T cells during tuberculosis

    Science.gov (United States)

    Sallin, Michelle A.; Sakai, Shunsuke; Kauffman, Keith D.; Young, Howard A.; Zhu, Jinfang; Barber, Daniel L.

    2017-01-01

    SUMMARY Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1 polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73+CXCR3+T-betdim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL-12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1+KLRG1+ Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69+CD103+ tissue resident phenotype effectors in lung. In contrast, Th1 cell-derived IFNγ inhibits the accumulation of intravascular CX3CR1+KLRG1+ Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis. PMID:28355562

  14. Contrast medium-induced nephropathy: the pathophysiology

    DEFF Research Database (Denmark)

    Persson, P B; Tepel, Martin

    2006-01-01

    A widespread, rather general, definition of contrast-induced nephropathy (CIN) is an impairment in renal function occurring within 3 days following the intravascular administration of contrast media (CM) and the absence of an alternative aetiology. In spite of the vast clinical importance of CIN...... haemodynamics, regional hypoxia, auto-, and paracrine factors (adenosine, endothelin, reactive oxygen species) to direct cytotoxic effects. Although these potential mediators of CIN will be discussed separately, several factors may act in concert to perturb kidney function after exposure to contrast media. From...... the current knowledge of the mechanisms causing CIN, it is not possible to recommend a certain class of contrast media, except to avoid large doses of CM of the first generation. From a pathophysiological perspective, volume expansion is effective in avoiding CIN, since water permeability of the collecting...

  15. Contrast-enhanced peripheral MRA. Technique and contrast agents

    International Nuclear Information System (INIS)

    Nielsen, Yousef W.; Thomsen, Henrik S.

    2012-01-01

    In the last decade contrast-enhanced magnetic resonance angiography (CE-MRA) has gained wide acceptance as a valuable tool in the diagnostic work-up of patients with peripheral arterial disease. This review presents current concepts in peripheral CE-MRA with emphasis on MRI technique and contrast agents. Peripheral CE-MRA is defined as an MR angiogram of the arteries from the aortic bifurcation to the feet. Advantages of CE-MRA include minimal invasiveness and lack of ionizing radiation. The basic technique employed for peripheral CE-MRA is the bolus-chase method. With this method a paramagnetic MRI contrast agent is injected intravenously and T1-weighted images are acquired in the subsequent arterial first-pass phase. In order to achieve high quality MR angiograms without interfering venous contamination or artifacts, a number of factors need to be taken into account. This includes magnetic field strength of the MRI system, receiver coil configuration, use of parallel imaging, contrast bolus timing technique, and k-space filling strategies. Furthermore, it is possible to optimize peripheral CE-MRA using venous compression techniques, hybrid scan protocols, time-resolved imaging, and steady-state MRA. Gadolinium(Gd)-based contrast agents are used for CE-MRA of the peripheral arteries. Extracellular Gd agents have a pharmacokinetic profile similar to iodinated contrast media. Accordingly, these agents are employed for first-pass MRA. Blood-pool Gd-based agents are characterized by prolonged intravascular stay, due to macromolecular structure or protein binding. These agents can be used for first-pass, as well as steady-state MRA. Some Gd-based contrast agents with low thermodynamic stability have been linked to development of nephrogenic systemic fibrosis in patients with severe renal insufficiency. Using optimized technique and a stable MRI contrast agent, peripheral CE-MRA is a safe procedure with diagnostic accuracy close to that of conventional catheter X

  16. Site requirements and kinetics of immune-dependent elimination of intravascularly administered lung stage schistosomula in mice immunized with highly irradiated cercariae of Schistosoma mansoni

    International Nuclear Information System (INIS)

    Mangold, B.L.; Dean, D.A.; Coulson, P.S.; Wilson, R.A.

    1986-01-01

    Experiments were performed to compare the migration and survival of 75Se-labeled schistosomes, introduced by percutaneous cercarial exposure or by intravascular administration of 7-day-old lung stage schistosomula, in control and irradiated cercaria-immunized mice. Schistosomula were intravascularly introduced into the lungs, systemic organs and liver by injection via the femoral vein (FV), left ventricle (LV), and superior mesenteric vein (SMV), respectively. The fate of challenge larvae was examined by autoradiography of host tissues and by recovery of adult worms. It was found that both normal and immune elimination were site-dependent. In control mice 45%-60% of cercarial penetrants and lung schistosomula injected into the FV and LV were recoverable as adult worms, while a significantly greater number (70%-85%) were recoverable when lung schistosomula were injected into the SMV. In immunized mice, parasites introduced as either cercariae or FV-injected schistosomula were both highly sensitive to immune elimination. LV-injected schistosomula were also sensitive but to a slightly lesser degree. In contrast, schistosomula placed directly in the liver by SMV injection were totally insensitive to immune elimination. It was concluded that elimination of schistosomula in irradiated cercaria-immunized mice occurs in the lungs and/or in the systemic organs, but not in the liver. Also, it was concluded that immune elimination is not a rapid process, since more than 7 days were required after intravascular challenge for the development of demonstrable differences between control and immunized mice

  17. Intravascular Ultrasound Imaging of Peripheral Arteries as an Adjunct to Balloon Angioplasty and Atherectomy

    International Nuclear Information System (INIS)

    Korogi, Yukunori; Hirai, Toshinori; Takahashi, Mutsumasa

    1996-01-01

    This article reviews many of the applications of intravascular ultrasound (US) imaging for peripheral arterial diseases. In vitro studies demonstrate an excellent correlation between ultrasound measurements of lumen and plaque crossectional area compared with histologic sections. In vivo clinical studies reveal the enhanced diagnostic capabilities of this technology compared with angiography. Intravascular US imaging can provide valuable information on the degree, eccentricity, and histologic type of stenosis before intervention, and on the morphological changes in the arterial wall and the extent of excision after intervention. Intravascular US may also serve as a superior index for gauging the diameter of balloon, stent, laser probe, and/or atherectomy catheter appropriate for a proposed intervention. Significant new insights into the mechanisms of balloon angioplasty and atherectomy have been established by intravascular US findings. Intravascular US imaging has been shown to be a more accurate method than angiography for determining the cross-sectional area of the arterial lumen, and for assessing severity of stenosis. Quantitative assessment of the luminal cross-sectional area after the balloon dilatation should be more accurate than angiography as intimal tears or dissections produced by the dilatation may not be accurately evaluated with angiography. At the present time, intravascular US is still a controversial imaging technique. Outcome studies are currently being organized to assess the clinical value and cost effectiveness of intravascular ultrasound in the context of these interventional procedures

  18. Molecular imaging with targeted contrast ultrasound.

    Science.gov (United States)

    Piedra, Mark; Allroggen, Achim; Lindner, Jonathan R

    2009-01-01

    Molecular imaging with contrast-enhanced ultrasound uses targeted microbubbles that are retained in diseased tissue. The resonant properties of these microbubbles produce acoustic signals in an ultrasound field. The microbubbles are targeted to diseased tissue by using certain chemical constituents in the microbubble shell or by attaching disease-specific ligands such as antibodies to the microbubble. In this review, we discuss the applications of this technique to pathological states in the cerebrovascular system including atherosclerosis, tumor angiogenesis, ischemia, intravascular thrombus, and inflammation. Copyright 2009 S. Karger AG, Basel.

  19. Contrast Materials

    Science.gov (United States)

    ... is mixed with water before administration liquid paste tablet When iodine-based and barium-sulfate contrast materials ... for patients with kidney failure or allergies to MRI and/or computed tomography (CT) contrast material. Microbubble ...

  20. Design and implementation of an intravascular brachytherapy installation in cardiology

    International Nuclear Information System (INIS)

    Prieto, C.; Vano, E.; Fernandez, J.M.; Sabate, M.; Galvan, Y.C.

    2001-01-01

    Intravascular Brachytherapy (IVB) is a very promising technique for reducing restenosis rates. However, neither the exact absolute dose needed nor the optimal spatial and temporal distribution of dose inside the vessel wall for a successful treatment, nor the physical dosimetry of the various radioactive sources and devices for dose delivery, are well known. In this paper, an overview will be given of the design strategy, the dosimetric and radiation protection-related problems that we have met during the implementation of this technique at San Carlos hospital, adopted or foreseen solutions, and future research fields that we intend to carry out in order to reduce uncertainties and to achieve a deeper knowledge of the parameters that have an influence on the treatment. (author)

  1. Robust intravascular optical coherence elastography by line correlations

    International Nuclear Information System (INIS)

    Soest, Gijs van; Mastik, Frits; Jong, Nico de; Steen, Anton F W van der

    2007-01-01

    We present a new method for intravascular optical coherence elastography, which is robust against motion artefacts. It employs the correlation between adjacent lines, instead of subsequent frames. Pressure to deform the tissue is applied synchronously with the line scan rate of the optical coherence tomography (OCT) instrument. The viability of the method is demonstrated with a simulation study. We find that the root mean square (rms) error of the displacement estimate is 0.55 μm, and the rms error of the strain is 0.6%. It is shown that high-strain spots in the vessel wall, such as observed at the sites of vulnerable atherosclerotic lesions, can be detected with the technique

  2. Emerging Technology Update Intravascular Photoacoustic Imaging of Vulnerable Atherosclerotic Plaque.

    Science.gov (United States)

    Wu, Min; Fw van der Steen, Antonius; Regar, Evelyn; van Soest, Gijs

    2016-10-01

    The identification of vulnerable atherosclerotic plaques in the coronary arteries is emerging as an important tool for guiding atherosclerosis diagnosis and interventions. Assessment of plaque vulnerability requires knowledge of both the structure and composition of the plaque. Intravascular photoacoustic (IVPA) imaging is able to show the morphology and composition of atherosclerotic plaque. With imminent improvements in IVPA imaging, it is becoming possible to assess human coronary artery disease in vivo . Although some challenges remain, IVPA imaging is on its way to being a powerful tool for visualising coronary atherosclerotic features that have been specifically associated with plaque vulnerability and clinical syndromes, and thus such imaging might become valuable for clinical risk assessment in the catheterisation laboratory.

  3. Evaluation of Disseminated Intravascular Coagulation in the Craniocerebral Traumas

    Directory of Open Access Journals (Sweden)

    Faruk Altinel

    2014-06-01

    Full Text Available Traumatic injury is one of the most important cause of disseminated intravascular coagulation (DIC. It occurs because of blood loss and hemodilution due to fluid resuscitation. The incidence of trauma associated DIC is mainly higher in the craniocerebral traumas. Even though craniocerebral trauma related DIC is well defined, the pathophysiology has been poorly characterized in the literature. Due to the fact that brain tissue is highly significant for procoagulant molecules, craniocerebral traumas are closely related to DIC. In the current study, 30 patients admitted to emergency room have been considered on the first and fifth day of admission to the hospital for the coagulation tests to evaluate DIC in both two groups. [Cukurova Med J 2014; 39(3.000: 488-495

  4. Positive intraluminal bowel contrast on computed tomography following oral ingestion of Kayexelate

    International Nuclear Information System (INIS)

    Zissin, R.; Stackievicz, R.; Osadchy, A.; Gayer, G.

    2008-01-01

    Our study presents the computed tomography (CT) manifestations of orally ingested kayexelate (a powdered form of sodium polystyrene sulphonate) used to treat hyperkalemia. Five patients with whom kayexelate appeared as high-attenuating intraluminal enteric content, similar to oral contrast material or leakage of intravascular contrast, are reported. Radiologists should be familiar with its appearance as it may mimic oral or vascular contrast within the gastrointestinal tract, a finding that may lead to a diagnostic error or misinterpretation. (author)

  5. Monte Carlo dosimetry of a tandem positioned beta-emitting intravascular brachytherapy source train

    International Nuclear Information System (INIS)

    Wallace, Steven A.; Schumer, Wendy; Horrigan, Mark

    2002-01-01

    Prevention of restenosis following interventional coronary procedures with catheter based beta-emitting sources is currently under clinical trial investigations. Systems utilizing fixed length source trains limit the clinician's ability to increase the radiation source length as required. A technique known as 'pull back' is used when the segment of artery requiring radiation is longer than the available fixed length source train. In this instance, tandem positioning of the fixed length source is used to treat the longer length of artery. The aim of this study was to examine the dosimetry of the junction region associated with pull back treatments using a commercially available 90 Sr/Y catheter based intravascular brachytherapy source train. Dose profiles were calculated, using the Monte Carlo code MCNP4B, at radial distances of 1.5, 2.0, and 2.5 mm for pull back techniques using 2.5 mm overlapping, abutting, and 2.5 mm spaced source trains. Results at the protocol prescription radius of 2 mm showed a junction dose elevated 61% above prescription for 2.5 mm overlapping source trains. For 2.5 mm spaced trains, this figure falls to 64% below prescription dose. In contrast, abutted source trains exhibited only a 1% depression below prescription dose in the junction region. The reference point dose rate per unit activity of this source was found to be consistent with previous studies

  6. Hemostasia normal y coagulación intravascular diseminada en obstetricia Normal hemostasis and disseminated intravascular clotting in Obstetrics

    Directory of Open Access Journals (Sweden)

    Danilo Nápoles Méndez

    2012-03-01

    Full Text Available En el período gravido - puerperal, la coagulación sanguínea sufre cambios que se impone conocer para interpretar correctamente esos trastornos cuando se presentan en esta etapa, teniendo en cuenta las posibles complicaciones y el peligro para la vida que pueden presentarse. El objetivo del presente artículo es proporcionar a los obstetras una revisión bibliográfica que les permita actualizarse acerca del tema y facilite su modo de actuación ante pacientes con coagulación intravascular diseminada. Se concluye que es preciso diagnosticar tempranamente el proceso en la fase bioquímica de bajo grado y aplicar en las féminas el tratamiento expedito de la enfermedad de base para eliminar las complicaciones o disminuir su ocurrenciaIn the period from pregnancy to puerperium, blood clotting suffers changes which are important to be known in order to interpret correctly those dysfunctions when they appear in this stage, keeping in mind the possible complications and the danger for life which can take place. The objective of the present work is to provide the obstetricians a literature review that allows them to be updated about the topic and facilitate their performance in case of patients with disseminated intravascular clotting. It is concluded that it is necessary to have an early diagnosis on the process during the low grade biochemical phase and to apply in these women the expedite treatment of the base disease to eliminate complications or to decrease their occurrence.

  7. The sliding rail system (monorail): description of a new technique for intravascular instrumentation and its application to coronary angioplasty.

    Science.gov (United States)

    Bonzel, T; Wollschläger, H; Kasper, W; Meinertz, T; Just, H

    1987-01-01

    The sliding rail technique is a new technique for intravascular instrumentation, especially coronary stenosis dilatation. The so-called monorail balloon catheter is the first device which can be used according to this technique. The monorail catheter has a single lumen shaft and only a short central tube within the distal balloon part. With the guidewire inserted into the tube, the balloon can be advanced or retracted on the guidewire as on a sliding rail. The most relevant improvements for coronary dilatation are steerability, contrast flow and rapid and easy exchangeability of balloon catheters and other intracoronary devices. These characteristics are felt to result in a more simple and time- and fluoroscopy-saving dilatation procedure. A special transfusion catheter may also improve procedural safety. The first clinical results in 69 patients with a success rate of 96%, an emergency bypass rate of two patients (one infarction) and a stenosis improvement of 58% confirm the theoretically conceived advantages.

  8. Local intravascular coagulation and fibrin deposition on intestinal ischemia-reperfusion in rats

    NARCIS (Netherlands)

    Schoots, Ivo G.; Levi, Marcel; Roossink, E. H. Paulina; Bijlsma, Pieter B.; van Gulik, Thomas M.

    2003-01-01

    Background. This study investigates intravascular coagulation and thrombotic obstruction in the splanchnic vasculature after intestinal ischemia in relation to epithelial integrity and function. Methods. Intestinal ischemia was induced in rats by superior mesenteric artery occlusion for 20 or 40

  9. Intravascular radiation for restenosis prevention: could it be the holy grail?

    International Nuclear Information System (INIS)

    King, S.B.

    1996-01-01

    This brief editorial discusses the use of intravascular radiation in preventing restenosis after angioplasty in coronary interventions. Results in porcine coronary arteries and clinical applications are briefly reported. (UK)

  10. New treatment strategies for disseminated intravascular coagulation based on current understanding of the pathophysiology

    NARCIS (Netherlands)

    Levi, Marcel; de Jonge, Evert; van der Poll, Tom

    2004-01-01

    A variety of clinical conditions may cause systemic activation of coagulation, ranging from insignificant laboratory changes to severe disseminated intravascular coagulation (DIC). DIC consists of a widespread, systemic activation of coagulation, resulting in diffuse fibrin deposition in small and

  11. Non-radiological contrast agents (MRI)

    International Nuclear Information System (INIS)

    Bonnemain, B.; Lautrou, J.; Meyer, D.; Doucet, D.

    1987-01-01

    Over the past few years, extensive research has been carried out in an attempt to develop contrast agents that could help improve both the performance (acquisition times) and the diagnostic efficacy of Magnetic Resonance Imaging (MRI) techniques. On the basis of physicochemical and pharmacological criteria discussed in this presentation, a few efficacious, well-tolerated compounds could be developed. Two of them, the gadolinium complexes Gd-DOTA and Gd-DTPA, are currently being tried in man. This first generation of contrast agents, which are aspecific markers of the intravascular space, has been shown to have good diagnostic potential in conventional MRI procedures. The diagnostic contribution of these contrast agents will probably be a most essential factor in new MRI techniques using low field strengh or fast imaging sequences [fr

  12. Comparison and evaluation of indicator dilution models for bolus of ultrasound contrast agents

    Czech Academy of Sciences Publication Activity Database

    Harabis, V.; Kolář, R.; Mézl, M.; Jiřík, Radovan

    2013-01-01

    Roč. 34, č. 2 (2013), s. 151-162 ISSN 0967-3334 R&D Projects: GA ČR GAP102/12/2380 Institutional support: RVO:68081731 Keywords : perfusion model * ultrasound * contrast agent * intravascular perfusion * tissue phantom Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.617, year: 2013

  13. Recent advances in contrast-enhanced magnetic resonance angiography

    International Nuclear Information System (INIS)

    Meaney, J.F.M.; Goyen, M.

    2007-01-01

    Magnetic resonance angiography (MRA) provides a means of visualizing vascular structures noninvasively and is increasingly replacing conventional X-ray angiography in routine use. Contrast-enhanced MRA (CE-MRA), in which gadolinium contrast agents are used to shorten the T1 relaxation, offers increased resolution and higher signal-to-noise ratio compared with earlier flow-dependent [time-of-flight (TOF) or phase-contrast (PC)] techniques. Currently available contrast agents differ in their ability to lower T1 values, and hence the choice of contrast agent is an important consideration in the successful use of CE-MRA. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first of a new class of intravascular contrast agents. This agent is extensively (approximately 85%) and reversibly bound to human serum albumin and is retained within the vasculature thus allowing steady-state imaging to be perform-ed. An additional benefit is that gado0fosveset offers higher relaxivity compared with other contrast agents, thus giving a lower blood T1 values which also makes it ideal for first-pass imaging. Clinical trials have consistently shown that gadofosveset enhanced MRA is more sensitive, specific and accurate than time-of-flight MRA, gives fewer uninterpretable scans and affords greater diagnostic confidence. Intravascular contrast agents such as gadofosveset, therefore, offer the potential for improved vascular imaging. (orig.)

  14. The Incidence of Intravascular Needle Entrance during Inferior Alveolar Nerve Block Injection.

    Science.gov (United States)

    Taghavi Zenouz, Ali; Ebrahimi, Hooman; Mahdipour, Masoumeh; Pourshahidi, Sara; Amini, Parisa; Vatankhah, Mahdi

    2008-01-01

    Dentists administer thousands of local anesthetic injections every day. Injection to a highly vascular area such as pterygomandibular space during an inferior alveolar nerve block has a high risk of intravascular needle entrance. Accidental intravascular injection of local anesthetic agent with vasoconstrictor may result in cardiovascular and central nervous system toxicity, as well as tachycardia and hypertension. There are reports that indicate aspiration is not performed in every injection. The aim of the present study was to assess the incidence of intravascular needle entrance in inferior alveolar nerve block injections. Three experienced oral and maxillofacial surgeons performed 359 inferior alveolar nerve block injections using direct or indirect techniques, and reported the results of aspiration. Aspirable syringes and 27 gauge long needles were used, and the method of aspiration was similar in all cases. Data were analyzed using t-test. 15.3% of inferior alveolar nerve block injections were aspiration positive. Intravascular needle entrance was seen in 14.2% of cases using direct and 23.3% of cases using indirect block injection techniques. Of all injections, 15.8% were intravascular on the right side and 14.8% were intravascular on the left. There were no statistically significant differences between direct or indirect block injection techniques (P = 0.127) and between right and left injection sites (P = 0.778). According to our findings, the incidence of intravascular needle entrance during inferior alveolar nerve block injection was relatively high. It seems that technique and maneuver of injection have no considerable effect in incidence of intravascular needle entrance.

  15. The Incidence of Intravascular Needle Entrance during Inferior Alveolar Nerve Block Injection

    Directory of Open Access Journals (Sweden)

    Sara Pourshahidi

    2008-04-01

    Full Text Available

    Background and aims. Dentists administer thousands of local anesthetic injections every day. Injection to a highly vascular area such as pterygomandibular space during an inferior alveolar nerve block has a high risk of intravascular needle entrance. Accidental intravascular injection of local anesthetic agent with vasoconstrictor may result in cardiovascular and central nervous system toxicity, as well as tachycardia and hypertension. There are reports that indicate aspiration is not performed in every injection. The aim of the present study was to assess the incidence of intravascular needle entrance in inferior alveolar nerve block injections.

    Materials and methods. Three experienced oral and maxillofacial surgeons performed 359 inferior alveolar nerve block injections using direct or indirect techniques, and reported the results of aspiration. Aspirable syringes and 27 gauge long needles were used, and the method of aspiration was similar in all cases. Data were analyzed using t-test.

    Results. 15.3% of inferior alveolar nerve block injections were aspiration positive. Intravascular needle entrance was seen in 14.2% of cases using direct and 23.3% of cases using indirect block injection techniques. Of all injections, 15.8% were intravascular on the right side and 14.8% were intravascular on the left. There were no statistically significant differences between direct or indirect block injection techniques (P = 0.127 and between right and left injection sites (P = 0.778.

    Conclusion. According to our findings, the incidence of intravascular needle entrance during inferior alveolar nerve block injection was relatively high. It seems that technique and maneuver of injection have no considerable effect in incidence of intravascular needle entrance.

  16. Gallium SPECT detection of neoplastic intravascular obstruction of the superior vena cava

    International Nuclear Information System (INIS)

    Swayne, L.C.; Kaplan, I.L.

    1989-01-01

    A rare case of an intravascular neoplastic obstruction of the superior vena cava is discussed. The lesion was detected with gallium single photon emission computed tomography (SPECT) despite a normal appearance on a concurrent radiographic CT study. A computer-generated composite SPECT-CT image confirmed the intravascular localization of the radioisotope, and a subsequent CT-guided transthoracic needle biopsy revealed a poorly differentiated adenocarcinoma

  17. Effector CD4+ T cells recognize intravascular antigen presented by patrolling monocytes.

    Science.gov (United States)

    Westhorpe, Clare L V; Norman, M Ursula; Hall, Pam; Snelgrove, Sarah L; Finsterbusch, Michaela; Li, Anqi; Lo, Camden; Tan, Zhe Hao; Li, Songhui; Nilsson, Susan K; Kitching, A Richard; Hickey, Michael J

    2018-02-21

    Although effector CD4 + T cells readily respond to antigen outside the vasculature, how they respond to intravascular antigens is unknown. Here we show the process of intravascular antigen recognition using intravital multiphoton microscopy of glomeruli. CD4 + T cells undergo intravascular migration within uninflamed glomeruli. Similarly, while MHCII is not expressed by intrinsic glomerular cells, intravascular MHCII-expressing immune cells patrol glomerular capillaries, interacting with CD4 + T cells. Following intravascular deposition of antigen in glomeruli, effector CD4 + T-cell responses, including NFAT1 nuclear translocation and decreased migration, are consistent with antigen recognition. Of the MHCII + immune cells adherent in glomerular capillaries, only monocytes are retained for prolonged durations. These cells can also induce T-cell proliferation in vitro. Moreover, monocyte depletion reduces CD4 + T-cell-dependent glomerular inflammation. These findings indicate that MHCII + monocytes patrolling the glomerular microvasculature can present intravascular antigen to CD4 + T cells within glomerular capillaries, leading to antigen-dependent inflammation.

  18. MRI phenotypes of localized intravascular coagulopathy in venous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Kevin S.H. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); Dowd, Christopher F.; Hess, Christopher P. [University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Mathes, Erin F.; Frieden, Ilona J. [University of California, San Francisco, Department of Dermatology, San Francisco, CA (United States); Rosbe, Kristina W. [University of California, San Francisco, Department of Otolaryngology, San Francisco, CA (United States); Hoffman, William Y. [University of California, San Francisco, Department of Surgery, San Francisco, CA (United States)

    2015-10-15

    The incidence of localized intravascular coagulopathy (LIC) in venous malformations varies with lesion size and location, as well as the presence of palpable phleboliths. The development of LIC can cause pain and hemorrhage and can progress to disseminated intravascular coagulopathy (DIC) and thromboembolic disease resulting in death in some cases. Early recognition of LIC can relieve symptoms and prevent progression to life-threatening complications. The aim of this work was to identify MRI features of venous malformation associated with LIC. We hypothesized that venous malformations with larger capacitance, slower flow and less physiological compression (greater stasis) were more likely to be associated with LIC. In this HIPAA-compliant and IRB-approved study, we retrospectively reviewed clinical records and MRI for consecutive patients undergoing evaluation of venous malformations at our multidisciplinary Birthmarks and Vascular Anomalies Center between 2003 and 2013. Inclusion required consensus diagnosis of venous malformation and availability of laboratory data and MRI; patients on anticoagulation or those previously undergoing surgical or endovascular treatment were excluded. LIC was diagnosed when D-dimer exceeded 1,000 ng/mL and/or fibrinogen was less than 200 mg/dL. Two board-certified radiologists assessed the following MRI features for each lesion: morphology (spongiform vs. phlebectatic), presence of phleboliths, size, location (truncal vs. extremity), and tissue type(s) involved (subcutis, muscle, bone and viscera). Univariate logistic regression analyses were used to test associations between LIC and MRI findings, and stepwise regression was applied to assess the significance of the individual imaging predictors. Seventy patients, 37 with LIC, met inclusion criteria during the 10-year study period (age: 14.5 +/- 13.6 years [mean +/- standard deviation]; 30 male, 40 female). Both elevated D-dimer and low fibrinogen were associated with the presence of

  19. MRI phenotypes of localized intravascular coagulopathy in venous malformations

    International Nuclear Information System (INIS)

    Koo, Kevin S.H.; Dowd, Christopher F.; Hess, Christopher P.; Mathes, Erin F.; Frieden, Ilona J.; Rosbe, Kristina W.; Hoffman, William Y.

    2015-01-01

    The incidence of localized intravascular coagulopathy (LIC) in venous malformations varies with lesion size and location, as well as the presence of palpable phleboliths. The development of LIC can cause pain and hemorrhage and can progress to disseminated intravascular coagulopathy (DIC) and thromboembolic disease resulting in death in some cases. Early recognition of LIC can relieve symptoms and prevent progression to life-threatening complications. The aim of this work was to identify MRI features of venous malformation associated with LIC. We hypothesized that venous malformations with larger capacitance, slower flow and less physiological compression (greater stasis) were more likely to be associated with LIC. In this HIPAA-compliant and IRB-approved study, we retrospectively reviewed clinical records and MRI for consecutive patients undergoing evaluation of venous malformations at our multidisciplinary Birthmarks and Vascular Anomalies Center between 2003 and 2013. Inclusion required consensus diagnosis of venous malformation and availability of laboratory data and MRI; patients on anticoagulation or those previously undergoing surgical or endovascular treatment were excluded. LIC was diagnosed when D-dimer exceeded 1,000 ng/mL and/or fibrinogen was less than 200 mg/dL. Two board-certified radiologists assessed the following MRI features for each lesion: morphology (spongiform vs. phlebectatic), presence of phleboliths, size, location (truncal vs. extremity), and tissue type(s) involved (subcutis, muscle, bone and viscera). Univariate logistic regression analyses were used to test associations between LIC and MRI findings, and stepwise regression was applied to assess the significance of the individual imaging predictors. Seventy patients, 37 with LIC, met inclusion criteria during the 10-year study period (age: 14.5 +/- 13.6 years [mean +/- standard deviation]; 30 male, 40 female). Both elevated D-dimer and low fibrinogen were associated with the presence of

  20. Renal Sympathetic Denervation System via Intraluminal Ultrasonic Ablation: Therapeutic Intravascular Ultrasound Design and Preclinical Evaluation.

    Science.gov (United States)

    Chernin, Gil; Szwarcfiter, Iris; Bausback, Yvonne; Jonas, Michael

    2017-05-01

    To assess the safety and performance of a nonfocused and nonballooned ultrasonic (US) catheter-based renal sympathetic denervation (RDN) system in normotensive swine. RDN with the therapeutic intravascular US catheter was evaluated in 3 experiments: (i) therapeutic intravascular US RDN vs a control group of untreated animals with follow-up of 30, 45, and 90 days (n = 6; n = 12 renal arteries for each group); (ii) therapeutic intravascular US RDN vs radiofrequency (RF) RDN in the contralateral artery in the same animal (n = 2; n = 4 renal arteries); and (iii) therapeutic intravascular US RDN in a recently stent-implanted renal artery (n = 2; n = 4 renal arteries). In the first experiment, therapeutic intravascular US RDN was safe, without angiographic evidence of dissection or renal artery stenosis. Neuronal tissue vacuolization, nuclei pyknosis, and perineuronal inflammation were evident after RDN, without renal artery wall damage. Norepinephrine levels were significantly lower after therapeutic intravascular US RDN after 30, 45, and 90 days compared with the control group (200.17 pg/mg ± 63.35, 184.75 pg/mg ± 44.51, and 203.43 pg/mg ± 58.54, respectively, vs 342.42 pg/mg ± 79.97). In the second experiment, deeper neuronal ablation penetrance was found with therapeutic intravascular US RDN vs RF RDN (maximal penetrance from endothelium of 7.0 mm vs 3.5 mm, respectively). There was less damage to the artery wall after therapeutic intravascular US RDN than with RF RDN, after which edema and injured endothelium were seen. In the third experiment, denervation inside the stent-implanted segments was feasible without damage to the renal artery wall or stent. The therapeutic intravascular US system performed safely and reduced norepinephrine levels. Deeper penetrance and better preservation of vessel wall were observed with therapeutic intravascular US RDN vs RF RDN. Neuronal ablations were observed in stent-implanted renal arteries. Copyright © 2017 SIR. Published

  1. Heartbeat OCT: in vivo intravascular megahertz-optical coherence tomography

    Science.gov (United States)

    Wang, Tianshi; Pfeiffer, Tom; Regar, Evelyn; Wieser, Wolfgang; van Beusekom, Heleen; Lancee, Charles T.; Springeling, Geert; Krabbendam, Ilona; van der Steen, Antonius F.W.; Huber, Robert; van Soest, Gijs

    2015-01-01

    Cardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging system that we called “Heartbeat OCT”, combining a fast Fourier Domain Mode Locked laser, fast pullback, and a micromotor actuated catheter, designed to examine a coronary vessel in less than one cardiac cycle. We acquired in vivo data sets of two coronary arteries in a porcine heart with both Heartbeat OCT, working at 2.88 MHz A-line rate, 4000 frames/s and 100 mm/s pullback speed, and with a commercial system. The in vivo results show that Heartbeat OCT provides faithfully rendered, motion-artifact free, fully sampled vessel wall architecture, unlike the conventional IV-OCT data. We present the Heartbeat OCT system in full technical detail and discuss the steps needed for clinical translation of the technology. PMID:26713214

  2. A Micromotor Catheter for Intravascular Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Tianshi Wang

    2015-03-01

    Full Text Available We have developed a new form of intravascular optical coherence tomography (IV-OCT that allows the extremely fast acquisition of high-resolution images of the coronary arteries. This process leads to much better image quality by eliminating cardiac motion artefacts and undersampling. It relies on a catheter that incorporates a synchronous micromotor with a diameter of 1.0 mm and a rotational speed of up to 5600 revolutions per second, enabling an IV-OCT frame rate of 5.6 kHz. This speed is matched by a wavelength-swept laser that generates up to 2.8 million image lines per second. With this setup, our team achieved IV-OCT imaging of up to 5600 frames per second (fps in vitro and 4000 fps in vivo, deployed at a 100 mm·s−1 pullback velocity. The imaging session is triggered by the electrocardiogram of the subject, and can scan a coronary artery in the phase of the heartbeat where the heart is at rest, providing a name for this new technology: the “Heartbeat OCT.”

  3. Intravascular trans-catheter fibrinolysis in acute arterial obstructions

    International Nuclear Information System (INIS)

    Roversi, R.; Rossi, C.; Ricci, S.; Gemelli, G.; Ciliberti, M.A.

    1987-01-01

    The author's experiences is reported on intravascular fibrinolytic therapy with urokinase in acute arterial obstructions. Thirty-eight patients were treated, from 1983 to 1986, for acute thrombosis and/or thromboembolization, 22 of which developed on an atherosclerotic lesion, and 10 on a surgical stenotic by-pass graft. A complete vascular recanalization has been obtained, at the end of the procedure, in 69,4% of the cases, 77,7% had a definite final clinical improvement. The results correspond to the medium statistical of the various casistics analyzed for comparison. Surgery has been performed on 27,7% of the patients. Complication have been observed in 8% of the cases. IAF technique is of greatest value in the treatment of those lesions; better results have been obtained with intra-thrombus injection of the drug (as emphasized by many authors) in association with PTA and surgery. A close cooperation between interventional radiology, vascular surgery and angiology is therefore necessary in this field

  4. Primary intravascular large B-cell lymphoma of pituitary

    Directory of Open Access Journals (Sweden)

    K R Anila

    2012-01-01

    Full Text Available A 68-year-old retired nurse, who was a known hypertensive on medication, presented with prolonged fever of 2-month duration without any clinical evidence of infection. On examination she had altered mental status. She also had other nonspecific complaints such as sleep disturbances, loss of weight, etc. On investigation, she was found to have anemia, thrombocytopenia, raised erythrocyte sedimentation rate (ESR, C-reactive protein (CRP, and lactate dehydrogenase (LDH values. She also had electrolyte imbalance. Radiological evaluation of brain showed mass lesion in the sella turcica, suggestive of pituitary adenoma. Biochemical evaluation showed hypopituitarism. Trans-sphenoidal biopsy was done. Based on histopathological and immunohistochemical findings a diagnosis of intravascular large B-cell lymphoma (IVLBCL of pituitary was made. Our patient′s condition deteriorated rapidly and she succumbed to her illness before therapy could be initiated. We are reporting this case because of the rare subtype of large B-cell lymphoma presenting at an extremely unusual primary site.

  5. Intravascular ultrasound based dose assessment in endovascular brachytherapy

    International Nuclear Information System (INIS)

    Catalano, Gianpiero; Tamburini, Vittorio; Colombo, Antonio; Nishida, Takahiro; Parisi, Giovanni; Mazzetta, Chiara; Orecchia, Roberto

    2003-01-01

    Background: the role of endovascular brachytherapy in restenosis prevention is well documented. Dose is usually prescribed at a fixed distance from the source axis by angiographic quantification of vessel diameter. Recently, intravascular ultrasound (IVUS) was introduced in dose prescription, allowing a better evaluation of the vessel anatomy. This study retrospectively explores the difference between prescription following angiographic vessel sizing and delivered dose calculated with IVUS. Methods and results: Seventeen lesions were studied with IVUS, identifying on irradiated segment, three sections on which measuring minimal and maximal distance from the centre of IVUS catheter to the adventitia; using dedicated software, corresponding doses were calculated. The dose ranged widely, with maximal and minimal values of 71.6 and 4.9 Gy; furthermore, heterogeneity in dose among different sections was observed. In the central section, the maximal dose was 206% of the one prescribed with the QCA model at 2 mm from the source axis, while the minimal dose was 96%. In proximal and distal sections, respective values were 182, 45, 243, and 122%. Conclusions: Our analysis confirmed the dose inhomogeneity delivered with an angiographic fixed-dose prescription strategy. A dose variation was found along the irradiated segment due to the differences in vessel thickness. IVUS emerged as an important tool in endovascular brachytherapy, especially for irregular-shaped vessels

  6. Intravascular ultrasound assessed incomplete stent apposition and stent fracture in stent thrombosis after bare metal versus drug-eluting stent treatment the Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Kosonen, Petteri; Vikman, Saila; Jensen, Lisette Okkels

    2012-01-01

    This prospective multicenter registry used intravascular ultrasound (IVUS) in patients with definite stent thrombosis (ST) to compare rates of incomplete stent apposition (ISA), stent fracture and stent expansion in patients treated with drug-eluting (DES) versus bare metal (BMS) stents. ST...... is a rare, but potential life threatening event after coronary stent implantation. The etiology seems to be multifactorial....

  7. Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies: a report from the International Working Group for Intravascular Optical Coherence Tomography Standardization and Validation

    DEFF Research Database (Denmark)

    Falk, Erling

    2012-01-01

    The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving...

  8. Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies : A report from the International Working Group for Intravascular Optical Coherence Tomography Standardization and Validation

    NARCIS (Netherlands)

    G.J. Tearney (Guillermo); E.S. Regar (Eveline); T. Akasaka (Takashi); S. Adriaenssens (Stef); P. Barlis (Peter); H.G. Bezerra (Hiram); B.E. Bouma (Brett); N. Bruining (Nico); J.-M. Cho (Jin-Man); S. Chowdhary (Saqib); M.A. Costa (Marco); R. de Silva (Ranil); J. Dijkstra (Jouke); C. di Mario (Carlo); D. Dudeck (Darius); E. Falk (Erling); M.D. Feldman (Marc); P.J. Fitzgerald (Peter); H.M. Garcia-Garcia (Hector); N. Gonzalo (Nieves); J.F. Granada (Juan); G. Guagliumi (Giulio); N.R. Holm (Niels); Y. Honda (Yasuhiro); F. Ikeno (Fumiaki); Y. Kawasaki; W. Kochman (Waclav); L. Koltowski (Lukasz); T. Kubo (Takashi); T. Kume (Teruyoshi); H. Kyono (Hiroyuki); C.C.S. Lam (Cheung Chi Simon); G. Lamouche (Guy); D.P. Lee (David); M.B. Leon (Martin); A. Maehara (Akiko); O. Manfrini (Olivia); G.S. Mintz (Gary); K. Mizuno (Kyiouchi); M-A.M. Morel (Marie-Angèle); S. Nadkarni (Seemantini); H. Okura (Hiroyuki); H. Otake (Hiromasa); A. Pietrasik (Arkadiusz); F. Prati (Francesco); L. Rber (Lorenz); M. Radu (Maria); N. Rieber (Nikolaus); M. Riga (Maria); S.M. Rollins; M. Rosenberg (Mireille); V. Sirbu (Vasile); P.W.J.C. Serruys (Patrick); K. Shimada; T. Shinke (Toshiro); J. Shite (Junya); E. Siegel (Eliot); S. Sonada (Shinjo); U. Suter (Ueli); S. Takarada (Shigeho); A. Tanaka (Atsushi); M. Terashima (Mitsuyasu); T. Troels (Thim); M. Uemura (Mayu); G.J. Ughi (Giovanni); H.M.M. van Beusekom (Heleen); A.F.W. van der Steen (Ton); G.A. van Es (Gerrit Anne); G. van Soest (Gijs); R. Virmani (Renu); S. Waxman (Sergio); N.J. Weissman (Neil); G. Weisz (Giora)

    2012-01-01

    textabstractObjectives: The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the

  9. Magnetic resonance imaging contrast agents: Overview and perspectives

    International Nuclear Information System (INIS)

    Yan Guoping; Robinson, Leslie; Hogg, Peter

    2007-01-01

    Magnetic resonance imaging (MRI) is a non-invasive clinical imaging modality, which has become widely used in the diagnosis and/or staging of human diseases around the world. Some MRI examinations include the use of contrast agents. The categorizations of currently available contrast agents have been described according to their effect on the image, magnetic behavior and biodistribution in the body, respectively. In this field, superparamagnetic iron oxide particles and soluble paramagnetic metal chelates are two main classes of contrast agents for MRI. This review outlines the research and development of MRI contrast agents. In future, the ideal MRI contrast agent will be focused on the neutral tissue- or organ-targeting materials with high relaxivity and specificity, low toxicity and side effects, suitable long intravascular duration and excretion time, high contrast enhancement with low dose in vivo, and with minimal cost

  10. Observation of Intravascular Changes of Superabsorbent Polymer Microsphere (SAP-MS) with Monochromatic X-Ray Imaging

    International Nuclear Information System (INIS)

    Tanimoto, Daigo; Ito, Katsuyoshi; Yamamoto, Akira; Sone, Teruki; Kobatake, Makito; Tamada, Tsutomu; Umetani, Keiji

    2010-01-01

    This study was designed to evaluate the intravascular transformation behavior of superabsorbent polymer microsphere (SAP-MS) in vivo macroscopically by using monochromatic X-ray imaging and to quantitatively compare the expansion rate of SAP-MS among different kinds of mixtures. Fifteen rabbits were used for our study and transcatheter arterial embolization (TAE) was performed for their auricular arteries using monochromatic X-ray imaging. We used three kinds of SAP-MS (particle diameter 100-150 μm) mixture as embolic spherical particles: SAP-MS(H) absorbed with sodium meglumine ioxaglate (Hexabrix 320), SAP-MS(V) absorbed with isosmolar contrast medium (Visipaque 270), and SAP-MS(S) absorbed with 0.9% sodium saline. The initial volume of SAP-MS particles just after TAE and its final volume 10 minutes after TAE in the vessel were measured to calculate the expansion rate (ER) (n = 30). Intravascular behavior of SAP-MS particles was clearly observed in real time at monochromatic X-ray imaging. Averaged initial volumes of SAP-MS (H) (1.24 x 10 7 μm 3 ) were significantly smaller (p 7 μm 3 ) and SAP-MS (S) (5.85 x 10 7 μm 3 ). Averaged final volumes of SAP-MS (H) were significantly larger than averaged initial volumes (4.41 x 10 7 μm 3 vs. 1.24 x 10 7 μm 3 ; p < 0.0001, ER = 3.55). There were no significant difference between averaged final volumes and averaged initial volumes of SAP-MS (V) and SAP-MS (S). SAP-MS (H), which first travels distally, reaches to small arteries, and then expands to adapt to the vessel lumen, is an effective particle as an embolic agent, causing effective embolization.

  11. Application of intravascular ultrasound in percutaneous coronary interventional therapy

    International Nuclear Information System (INIS)

    Wang Jingping; Li Bao; An Jian; Yang Bin; Wang Zhongchao; Wang Rijun; Zhang Wutang; Lei Xinyu; Wang Huixian; Lu Lifang; Gao Yongli

    2009-01-01

    Objective: To evaluate intravascular ultrasound (IVUS)in demonstrating the characteristics of coronary plaque and in implanting the coronary stent. Methods: Before stent implantation, IVUS was used to observe the plaque character/sties(soft, fibrotic, calcified or mixed) as well as the eccentric degree in 28 patients with angiographically-proved single coronary branch lesion. The minimal luminal diameter, minimal cross-sectional area and plaque area were measured. After stent deployment the above measurements were repeated, and the location, symmetrical index and expansion of the stent were observed. Results: A total of 36 stents was implanted in 28 patients with coronary disease. After the procedure the minimal luminal diameter and the minimal cross-sectional area was increased, while the plaque area was decreased. The difference between the values before and after the stent implantation was statistically significant (P<0.01). IVUS after stent deployment found that in all cases the stent had a nice location and covered the lesion completely with no interlayer at its both ends. Excellent expansion of the stent was seen in 30 cases (83.3%). Insufficient expansion occurred in 3 cases and undesirable contact of the stent to the arterial wall was found in 3 cases (16.7%). In such circumstances, one size bigger low-compliance balloon dilatation was adopted, or the original balloon was used again with higher pressure (18-22 atm), in order to expand the stent once more, and good results accord with IVUS optimal criteria were obtained. Conclusions: IVUS can clearly demonstrate the pathological features of the coronary lesions, such as plaque type, eccentric degree, luminal diameter, cross-sectional area and plaque area, which are very helpful in guiding the selection of the proper stent before the procedure, and are also very useful in evaluating the location, expansion of the stent as well as the stent-to-wall contact condition after the procedure. (authors)

  12. Intravascular papillary endothelial hyperplasia: magnetic resonance imaging of finger lesions

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jinkyeong; Kim, Jee-Young [The Catholic University of Korea, Department of Radiology, St. Vincent' s Hospital, College of Medicine, Suwon, Gyeonggi-do (Korea, Republic of); Yoo, Changyoung [The Catholic University of Korea, Department of Hospital Pathology, St. Vincent' s Hospital, College of Medicine, Suwon, Gyeonggi-do (Korea, Republic of)

    2016-02-15

    To describe magnetic resonance imaging (MRI) features of intravascular papillary endothelial hyperplasia (IPEH), to identify findings differentiating IPEH of the finger from that of other locations, and to correlate these with pathology. Nineteen patients with 20 I.E. masses of the finger (n = 13) and other locations (n = 7) were evaluated. All patients underwent MRI, and the results were correlated with pathology. Seventeen IPEHs, including all IPEHs of the finger, were located in the subcutis, the three other lesions in the muscle layer. On T1WI, all masses were isointense or slightly hyperintense. IPEHs of the finger (n = 13) revealed focal hyperintense nodules (n = 2) or central hypointensity (n = 2) on T1WI, hypointensity with a hyperintense rim (n = 7), hyperintensity with hypointense nodules (n = 5), or isointensity with a hypointense rim (n = 1) on T2WI, and rim enhancement (n = 5), heterogeneous enhancement with nodular nonenhanced areas (n = 6), peripheral nodular enhancement (n = 1), or no enhancement (n = 1) on gadolinium-enhanced T1WI. IPEHs of other locations (n = 7) demonstrated focal hyperintense nodules (n = 5) on T1WI, hyperintensity with hypointense nodules (n = 5) or heterogeneous signal intensity (n = 2) on T2WI, and rim or rim and septal enhancement (n = 6) or peripheral nodular enhancement (n = 1). Microscopically, IPEHs were composed of thrombi that were hypointense on T2WI and papillary endothelial proliferations that showed T2 hyperintensity and enhancement. MRI of finger IPEH reveals well-demarcated subcutaneous masses with hypointensity or hypointense nodules with peripheral hyperintensity on T2WI, as well as peripheral enhancement. T1 hyperintense nodules, internal heterogeneity on T2WI, and septal enhancement are more common in IPEH of other locations. (orig.)

  13. ARCOCT: Automatic detection of lumen border in intravascular OCT images.

    Science.gov (United States)

    Cheimariotis, Grigorios-Aris; Chatzizisis, Yiannis S; Koutkias, Vassilis G; Toutouzas, Konstantinos; Giannopoulos, Andreas; Riga, Maria; Chouvarda, Ioanna; Antoniadis, Antonios P; Doulaverakis, Charalambos; Tsamboulatidis, Ioannis; Kompatsiaris, Ioannis; Giannoglou, George D; Maglaveras, Nicos

    2017-11-01

    Intravascular optical coherence tomography (OCT) is an invaluable tool for the detection of pathological features on the arterial wall and the investigation of post-stenting complications. Computational lumen border detection in OCT images is highly advantageous, since it may support rapid morphometric analysis. However, automatic detection is very challenging, since OCT images typically include various artifacts that impact image clarity, including features such as side branches and intraluminal blood presence. This paper presents ARCOCT, a segmentation method for fully-automatic detection of lumen border in OCT images. ARCOCT relies on multiple, consecutive processing steps, accounting for image preparation, contour extraction and refinement. In particular, for contour extraction ARCOCT employs the transformation of OCT images based on physical characteristics such as reflectivity and absorption of the tissue and, for contour refinement, local regression using weighted linear least squares and a 2nd degree polynomial model is employed to achieve artifact and small-branch correction as well as smoothness of the artery mesh. Our major focus was to achieve accurate contour delineation in the various types of OCT images, i.e., even in challenging cases with branches and artifacts. ARCOCT has been assessed in a dataset of 1812 images (308 from stented and 1504 from native segments) obtained from 20 patients. ARCOCT was compared against ground-truth manual segmentation performed by experts on the basis of various geometric features (e.g. area, perimeter, radius, diameter, centroid, etc.) and closed contour matching indicators (the Dice index, the Hausdorff distance and the undirected average distance), using standard statistical analysis methods. The proposed method was proven very efficient and close to the ground-truth, exhibiting non statistically-significant differences for most of the examined metrics. ARCOCT allows accurate and fully-automated lumen border

  14. Cryospectrophotometric determination of tumor intravascular oxyhemoglobin saturations: dependence on vascular geometry and tumor growth.

    Science.gov (United States)

    Fenton, B M; Rofstad, E K; Degner, F L; Sutherland, R M

    1988-12-21

    To delineate the complex relationships between overall tumor oxygenation and vascular configuration, intravascular oxyhemoglobin (HbO2) saturation distributions were measured with cryospectrophotometric techniques. Four factors related to vascular morphometry and tumor growth were evaluated: a) vessel diameter, b) distance of vessel from the tumor surface, c) tumor volume, and d) vascular density. To measure intertumor heterogeneity, two murine sarcomas (RIF-1 and KHT) and two human ovarian carcinoma xenografts (OWI and MLS) were utilized. In contrast to skeletal muscle, a preponderance of very low HbO2 saturations was observed for both large and small tumors of all lines. Saturations up to about 90% were also generally present, however, even in very large tumors. Variations in vascular configuration were predominantly tumor-line dependent rather than due to inherent characteristics of the host vasculature, and widely disparate HbO2 distributions were found for alternate lines implanted in identical host mice. Although peripheral saturations remained fairly constant with tumor growth, HbO2 values were markedly lower for vessels nearer the tumor center and further decreased with increasing tumor volume. HbO2 saturations did not change substantially with increasing vascular density (except for KHT tumors), although density did decrease with increasing distance from tumor surface. Combined effects of vessel diameter, tumor volume, and vessel location on HbO2 saturations were complex and varied markedly with both tumor line and vessel class. For specific classes, HbO2 distributions correlated closely with radiobiological hypoxic fractions, i.e., for tumor lines in which hypoxic fraction increased substantially with tumor volume, corresponding HbO2 values decreased, while for lines in which hypoxic fraction remained constant, HbO2 values also were unchanged. Although these trends may also be a function of differing oxygen consumption rates between tumor lines

  15. Voxel-based plaque classification in coronary intravascular optical coherence tomography images using decision trees

    Science.gov (United States)

    Kolluru, Chaitanya; Prabhu, David; Gharaibeh, Yazan; Wu, Hao; Wilson, David L.

    2018-02-01

    Intravascular Optical Coherence Tomography (IVOCT) is a high contrast, 3D microscopic imaging technique that can be used to assess atherosclerosis and guide stent interventions. Despite its advantages, IVOCT image interpretation is challenging and time consuming with over 500 image frames generated in a single pullback volume. We have developed a method to classify voxel plaque types in IVOCT images using machine learning. To train and test the classifier, we have used our unique database of labeled cadaver vessel IVOCT images accurately registered to gold standard cryoimages. This database currently contains 300 images and is growing. Each voxel is labeled as fibrotic, lipid-rich, calcified or other. Optical attenuation, intensity and texture features were extracted for each voxel and were used to build a decision tree classifier for multi-class classification. Five-fold cross-validation across images gave accuracies of 96 % +/- 0.01 %, 90 +/- 0.02% and 90 % +/- 0.01 % for fibrotic, lipid-rich and calcified classes respectively. To rectify performance degradation seen in left out vessel specimens as opposed to left out images, we are adding data and reducing features to limit overfitting. Following spatial noise cleaning, important vascular regions were unambiguous in display. We developed displays that enable physicians to make rapid determination of calcified and lipid regions. This will inform treatment decisions such as the need for devices (e.g., atherectomy or scoring balloon in the case of calcifications) or extended stent lengths to ensure coverage of lipid regions prone to injury at the edge of a stent.

  16. Alterations of serum potassium, serum magnesium and adenosine diphosphate due to various contrast media containing iodine

    International Nuclear Information System (INIS)

    Lehrberger, G.

    1979-01-01

    As an introduction of the chemical structure of contrast media is explained. Then follows a survey about the complication rates in examinations with intravascularly applicable iodine-containing contrast media. In the next part clinical symptoms and signs of general and localized contrast media incompatibility reactions, the contrast medium protein reaction and the relationship between allergic reaction and contrast medium are explained. It was tried to attribute the large amount of side-effects to one primary reaction. In this connection the three above-mentioned components were investigated. (orig./MG) [de

  17. Contrast settling in cerebral aneurysm angiography

    International Nuclear Information System (INIS)

    Wang Zhijie; Hoffmann, Kenneth R; Guterman, Lee R; Wang Zhou; Rudin, Stephen; Meng Hui

    2005-01-01

    During angiography, blood flow is visualized with a radiopaque contrast agent, which is denser than blood. In complex vasculature, such as cerebral saccular aneurysms, the density difference may produce an appreciable gravity effect, where the contrast material separates from blood and settles along the gravity direction. Although contrast settling has been occasionally reported before, the fluid mechanics behind it have not been explored. Furthermore, the severity of contrast settling in cerebral aneurysms varies significantly from case to case. Therefore, a better understanding of the physical principles behind this phenomenon is needed to evaluate contrast settling in clinical angiography. In this study, flow in two identical groups of sidewall aneurysm models with varying parent-vessel curvature was examined by angiography. Intravascular stents were deployed into one group of the models. To detect contrast settling, we used lateral view angiography. Time-intensity curves were analysed from the angiographic data, and a computational fluid dynamic analysis was conducted. Results showed that contrast settling was strongly related to the local flow dynamics. We used the Froude number, a ratio of flow inertia to gravity force, to characterize the significance of gravity force. An aneurysm with a larger vessel curvature experienced higher flow, which resulted in a larger Froude number and, thus, less gravitational settling. Addition of a stent reduced the aneurysmal flow, thereby increasing the contrast settling. We found that contrast settling resulted in an elevated washout tail in the time-intensity curve. However, this signature is not unique to contrast settling. To determine whether contrast settling is present, a lateral view should be obtained in addition to the anteroposterior (AP) view routinely used clinically so as to rule out contrast settling and hence to enable a valid time-intensity curve analysis of blood flow in the aneurysm

  18. Contrast media

    International Nuclear Information System (INIS)

    Decazes, Ph.

    2004-01-01

    The Guerbet firm, which holds 69% of the capital on the contrast media for medical imagery, could sale about 20% of this capital in order to accelerate its development in the United States, one of its next market with the Japan. (O.M.)

  19. Currently available methodologies for the processing of intravascular ultrasound and optical coherence tomography images.

    Science.gov (United States)

    Athanasiou, Lambros; Sakellarios, Antonis I; Bourantas, Christos V; Tsirka, Georgia; Siogkas, Panagiotis; Exarchos, Themis P; Naka, Katerina K; Michalis, Lampros K; Fotiadis, Dimitrios I

    2014-07-01

    Optical coherence tomography and intravascular ultrasound are the most widely used methodologies in clinical practice as they provide high resolution cross-sectional images that allow comprehensive visualization of the lumen and plaque morphology. Several methods have been developed in recent years to process the output of these imaging modalities, which allow fast, reliable and reproducible detection of the luminal borders and characterization of plaque composition. These methods have proven useful in the study of the atherosclerotic process as they have facilitated analysis of a vast amount of data. This review presents currently available intravascular ultrasound and optical coherence tomography processing methodologies for segmenting and characterizing the plaque area, highlighting their advantages and disadvantages, and discusses the future trends in intravascular imaging.

  20. Neuroimaging: do we really need new contrast agents for MRI?

    International Nuclear Information System (INIS)

    Roberts, T.P.L.; Chuang, N.; Roberts, H.C.

    2000-01-01

    The use of exogenous contrast media in magnetic resonance imaging of the brain has brought dramatic improvement in the sensitivity of detection and delineation of pathological structures, such as primary and metastatic brain tumors, inflammation and ischemia. Disruption of the blood brain barrier leads to accumulation of the intravenously injected contrast material in the extravascular space, leading to signal enhancement. Magnetic resonance angiography benefits from T 1 -shortening effects of contrast agent, improving small vessel depiction and providing vascular visualization even in situations of slow flow. High speed dynamic MRI after bolus injection of contrast media allows tracer kinetic modeling of cerebral perfusion. Progressive enhancement over serial post-contrast imaging allows modeling of vascular permeability and thus quantitative estimation of the severity of blood brain barrier disruption. With such an array of capabilities and ever improving technical abilities, it seems that the role of contrast agents in MR neuroimaging is established and the development of new agents may be superfluous. However, new agents are being developed with prolonged intravascular residence times, and with in-vivo binding of ever-increasing specificity. Intravascular, or blood pool, agents are likely to benefit magnetic resonance angiography of the carotid and cerebral vessels; future agents may allow the visualization of therapeutic drug delivery, the monitoring of, for example, gene expression, and the imaging evaluation of treatment efficacy. So while there is a substantial body of work that can be performed with currently available contrast agents, especially in conjunction with optimized image acquisition strategies, post processing, and mathematical analysis, there are still unrealized opportunities for novel contrast agent introduction, particularly those exploiting biological specificity. This article reviews the current use of contrast media in magnetic resonance

  1. Polymeric nanoparticles as OCT contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Al Rawashdeh, Wa' el [RWTH Aachen University, Experimental Molecular Imaging (Germany); Kray, Stefan [RWTH Aachen University, Institute for Semiconductor Electronics (Germany); Pich, Andrij; Pargen, Sascha; Balaceanu, Andreea [RWTH Aachen University, Interactive Material Research (DWI) (Germany); Lenz, Markus; Spoeler, Felix [RWTH Aachen University, Institute for Semiconductor Electronics (Germany); Kiessling, Fabian, E-mail: fkiessling@ukaachen.de; Lederle, Wiltrud [RWTH Aachen University, Experimental Molecular Imaging (Germany)

    2012-12-15

    In this study, the optical properties of two nano-sized polymer colloids in optical coherence tomography (OCT) were compared in vitro with respect to their potential use as contrast agents. We used two types of particles: compact hydrophobic spherical polystyrene (PS) particles and soft water-swollen nanogel (NG) particles both with grafted hydrophilic shell, both prepared at two different sizes (PS at 300 and 150 nm, NG at 300 and 200 nm). The OCT backscattering signals of the particles in a vessel-mimicking highly scattering agar/TiO{sub 2} phantom were compared on either number of particles or weight percent. Larger particles and higher concentrations produced higher OCT contrast. At each concentration tested, a markedly higher contrast was achieved by PS particles than NG particles. PS particles generated a markedly higher OCT contrast than the phantom at concentrations of at least 1 Multiplication-Sign 10{sup 10} or 0.1 % for PS 300 nm and at least 3 Multiplication-Sign 10{sup 11} particles/mL or 0.4 % for PS 150 nm. The contrast generated by NG 300 nm was above the phantom contrast at concentrations of at least 3 Multiplication-Sign 10{sup 11} particles/mL or 1 %, whereas NG 200 nm only at 4 %. At any given weight percent, the differences in OCT contrast between differently sized particles were much less evident than in the comparison based on particle number. PS 300 nm generated also a good contrast ex vivo on chicken muscle tissue. These results strongly suggest that PS spheres have strong potential as intravascular OCT contrast agent, while NG particles need further contrast enhancer for being used as OCT contrast agent.

  2. Perioperative Intravascular Fluid Assessment and Monitoring: A Narrative Review of Established and Emerging Techniques

    Directory of Open Access Journals (Sweden)

    Sumit Singh

    2011-01-01

    Full Text Available Accurate assessments of intravascular fluid status are an essential part of perioperative care and necessary in the management of the hemodynamically unstable patient. Goal-directed fluid management can facilitate resuscitation of the hypovolemic patient, reduce the risk of fluid overload, reduce the risk of the injudicious use of vasopressors and inotropes, and improve clinical outcomes. In this paper, we discuss the strengths and limitations of a spectrum of noninvasive and invasive techniques for assessing and monitoring intravascular volume status and fluid responsiveness in the perioperative and critically ill patient.

  3. Monooxignase ensymic system of a liver of rats exposed to intravascular laser irradiation of blood

    International Nuclear Information System (INIS)

    Ibadova, G.A.

    1997-01-01

    Experimental study of the dynamic monooxidation of liver enzymic system was carried out on rats with experimental salmonellosis and the influence of the blood intravascular laser irradiation of blood on these enzymes was revealed. It was determined that by experimental salmonellosis oppression of the MOES activity of hepatocytes occurred. The blood intravascular irradiation by He-Ne laser promotes MOES oppression in rats suffered from salmonellosis. IVLIB as well as UV-laser show pronounced effect on the enzymes detoxication protection, mobilize their resistance to endogenic intoxication under the conditions of experimental salmonellosis. (author)

  4. Leiomyosarcoma of the Uterus with Intravascular Tumor Extension and Pulmonary Tumor Embolism

    International Nuclear Information System (INIS)

    McDonald, Douglas K.; Kalva, Sanjeeva P.; Fan, C.-M.; Vasilyev, Aleksandr

    2007-01-01

    We report the case of a 48-year-old woman presenting with recurrent uterine leiomyosarcoma (LMS) associated with right iliac vein and inferior vena cava (IVC) invasion and left lower lobe pulmonary tumor embolus. Because the prognosis and treatment differ from that of thrombotic pulmonary emboli, the differentiating imaging characteristics of intravascular tumor embolism are reviewed. To our knowledge, only two other cases of intravenous uterine leiomyosarcomatosis have been described in the existing literature, and this is the first reported case of the entity with associated intravascular tumor embolism

  5. Intravascular brachytherapy in prevention of the secondary restenosis angioplasty transluminal coronaries

    International Nuclear Information System (INIS)

    Mejia, S.

    2001-01-01

    The radiotherapy coronary intravascular has demonstrated in a convincing way in clinical and experimental studies that produces a favorable decrease of the restenosis process. There is enough evidence to define this technique as the main current therapeutic option in the handling of the reestenosis intra stent. Accumulated experience exists of up to 3 years in patient's treaties with radiation gamma and multiple studies in several centers that demonstrate similar benefits with issuing beta. The present articulates it revises a series of radiotherapy systems and makes a setting a day on the employment of the brachytherapy intravascular in cardiologic patient

  6. Intravascular ultrasound evaluation of a pseudolesion created by stent placement in the right artery.

    Science.gov (United States)

    Zientek, D M; Rodgers, G P

    1999-10-01

    The creation of a pseudolesion after guidewire placement in tortuous arterial segments is a well recognized phenomenon. Intravascular ultrasound has been useful in assessing deployment of intracoronary stents and equivocal angiographic findings. We present a case in which a pseudolesion was not observed until after placement of an intracoronary stent. Intravascular ultrasound demonstrated no dissection or significant lesion; however, there was focal calcification just distal to the stent providing a substrate for the distorted vessel architecture. The lesion resolved with removal of the guidewire.

  7. Use of an Intravascular Fluorescent Continuous Glucose Sensor in ICU Patients

    NARCIS (Netherlands)

    Strasma, Paul J.; Finfer, Simon; Flower, Oliver; Hipszer, Brian; Kosiborod, Mikhail; Macken, Lewis; Sechterberger, Marjolein; van der Voort, Peter H. J.; DeVries, J. Hans; Joseph, Jeffrey I.

    2015-01-01

    Hyperglycemia and hypoglycemia are associated with adverse clinical outcomes in intensive care patients. In product development studies at 4 ICUs, the safety and performance of an intravascular continuous glucose monitoring (IV-CGM) system was evaluated in 70 postsurgical patients. The GluCath

  8. Disseminated intravascular coagulation or acute coagulopathy of trauma shock early after trauma? A prospective observational study

    DEFF Research Database (Denmark)

    Johansson, Per Ingemar; Sorensen, Anne Marie; Perner, Anders

    2011-01-01

    ABSTRACT: INTRODUCTION: It is debated whether the early trauma induced coagulopathy (TIC) in severely injured patients reflects disseminated intravascular coagulation (DIC) with a fibrinolytic phenotype, acute coagulopathy of trauma shock (ACoTS) or yet other entities. This study investigated the...

  9. Prospective validation of the International Society of Thrombosis and Haemostasis scoring system for disseminated intravascular coagulation

    NARCIS (Netherlands)

    Bakhtiari, Kamran; Meijers, Joost C. M.; de Jonge, Evert; Levi, Marcel

    2004-01-01

    Objectives: A diagnosis of disseminated intravascular coagulation (DIC) is hampered by the lack of an accurate diagnostic test. Based on the retrospective analysis of studies in patients with DIC, a scoring system (0-8 points) using simple and readily available routine laboratory tests has been

  10. Disseminated intravascular coagulation as an unusual presentation of an Epstein-Barr virus infection

    NARCIS (Netherlands)

    van Steijn, JHM; van Tol, KM; van Essen, LH; Gans, ROB

    2000-01-01

    Epstein-Barr viral (EBV)-infection usually presents as fever, sore throat, fatigue, lymphadenopathy and atypical lymphocytosis. We describe a patient with disseminated intravascular coagulation as the presenting symptom caused by a primary EBV infection. (C) 2000 Elsevier Science B.V. All rights

  11. Contrast media: interactions with other drugs and clinical tests

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Exley, C.M.; Thomsen, Henrik S.

    2005-01-01

    Many patients with multiple medical problems who are receiving a variety of drugs are investigated with imaging techniques which require intravascular contrast media. The Contrast Media Safety Committee of the European Society of Urogenital Radiology therefore decided to review the literature and to draw up simple guidelines on interactions between contrast media and other drugs. An extensive literature search was carried out and summarized in a report. Based on the available information, simple guidelines have been drawn up. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela. Contrast media may interact with other drugs, and may interfere with isotope studies and biochemical measurements. Awareness of the patient drug history is important to avoid potential hazards. Simple guidelines are presented. (orig.)

  12. Contrast-enhanced MRI of the lung

    International Nuclear Information System (INIS)

    Kauczor, Hans-Ulrich; Kreitner, Karl-Friedrich

    2000-01-01

    The lung has long been neglected by MR imaging. This is due to unique intrinsic difficulties: (1) signal loss due to cardiac pulsation and respiration; (2) susceptibility artifacts caused by multiple air-tissue interfaces; (3) low proton density. There are many MR strategies to overcome these problems. They consist of breath-hold imaging, respiratory and cardiac gating procedures, use of short repetition and echo times, increase of the relaxivity of existing spins by administration of intravenous contrast agents, and enrichment of spin density by hyperpolarized noble gases or oxygen. Improvements in scanner performance and frequent use of contrast media have increased the interest in MR imaging and MR angiography of the lung. They can be used on a routine basis for the following indications: characterization of pulmonary nodules, staging of bronchogenic carcinoma, in particular assessment of chest wall invasion; evaluation of inflammatory activity in interstitial lung disease; acute pulmonary embolism, chronic thromboembolic pulmonary hypertension, vascular involvement in malignant disease; vascular abnormalities. Future perspectives include perfusion imaging using extracellular or intravascular (blood pool) contrast agents and ventilation imaging using inhalation of hyperpolarized noble gases, of paramagnetic oxygen or of aerosolized contrast agents. These techniques represent new approaches to functional lung imaging. The combination of visualization of morphology and functional assessment of ventilation and perfusion is unequalled by any other technique

  13. Contrast media osmolality and plasma volume changes

    International Nuclear Information System (INIS)

    Hine, A.L.; Lui, D.; Dawson, P.; Middlesex Hospital, London

    1985-01-01

    A theoretical and experimental study of the plasma volume expansion consequent on the hyperosmolality of contrast media is presented. In the case of the ratio 1.5 media theory and experiment coincide closely but in the case of the ratio 3 media the observed changes exceed the predicted. It is proposed that this is due partly to the slower diffusion of the ratio 3 media out of the intravascular space and partly due to the fact that the osmotic load presented by these media is greater than would be expected from a study of their commercial solutions in which osmolality is reduced by molecular aggregation. The implications for the relative haemodynamic effects of different contrast media are discussed. The osmotic effects of contrast media also play a part in determining the image quality achievable in intravenous digital subtraction angiography (IV-DSA). It is predicted that ratio 3 contrast media will give better quality images in IV-DSA than ratio 1.5 media. (orig.)

  14. Assessment of the coronary venous system in heart failure patients by blood pool agent enhanced whole-heart MRI

    Energy Technology Data Exchange (ETDEWEB)

    Manzke, Robert [University Hospital of Ulm, Department of Internal Medicine II, Ulm (Germany); Philips Research Europe, Clinical Sites Research, Hamburg (Germany); Binner, Ludwig; Bornstedt, Axel; Merkle, Nico; Lutz, Anja; Gradinger, Robert [University Hospital of Ulm, Department of Internal Medicine II, Ulm (Germany); Rasche, Volker [University Hospital of Ulm, Department of Internal Medicine II, Ulm (Germany); Experimental Cardiovascular Imaging, Internal Medicine II, Ulm (Germany)

    2011-04-15

    To investigate the feasibility of MRI for non-invasive assessment of the coronary sinus (CS) and the number and course of its major tributaries in heart failure patients. Fourteen non-ischaemic heart failure patients scheduled for cardiac resynchronisation therapy (CRT) underwent additional whole-heart coronary venography. MRI was performed 1 day before device implantation. The visibility, location and dimensions of the CS and its major tributaries were assessed and the number of potential implantation sites identified. The MRI results were validated by X-ray venography conventionally acquired during the device implantation procedure. The right atrium (RA), CS and mid-cardiac vein (MCV) could be visualised in all patients. 36% of the identified candidate branches were located posterolaterally, 48% laterally and 16% anterolaterally. The average diameter of the CS was quantified as 9.8 mm, the posterior interventricular vein (PIV) 4.6 mm, posterolateral segments 3.3 mm, lateral 2.9 mm and anterolateral 2.9 mm. Concordance with X-ray in terms of number and location of candidate branches was given in most cases. Contrast-enhanced MRI venography appears feasible for non-invasive pre-interventional assessment of the course of the CS and its major tributaries. (orig.)

  15. Assessment of the coronary venous system in heart failure patients by blood pool agent enhanced whole-heart MRI

    International Nuclear Information System (INIS)

    Manzke, Robert; Binner, Ludwig; Bornstedt, Axel; Merkle, Nico; Lutz, Anja; Gradinger, Robert; Rasche, Volker

    2011-01-01

    To investigate the feasibility of MRI for non-invasive assessment of the coronary sinus (CS) and the number and course of its major tributaries in heart failure patients. Fourteen non-ischaemic heart failure patients scheduled for cardiac resynchronisation therapy (CRT) underwent additional whole-heart coronary venography. MRI was performed 1 day before device implantation. The visibility, location and dimensions of the CS and its major tributaries were assessed and the number of potential implantation sites identified. The MRI results were validated by X-ray venography conventionally acquired during the device implantation procedure. The right atrium (RA), CS and mid-cardiac vein (MCV) could be visualised in all patients. 36% of the identified candidate branches were located posterolaterally, 48% laterally and 16% anterolaterally. The average diameter of the CS was quantified as 9.8 mm, the posterior interventricular vein (PIV) 4.6 mm, posterolateral segments 3.3 mm, lateral 2.9 mm and anterolateral 2.9 mm. Concordance with X-ray in terms of number and location of candidate branches was given in most cases. Contrast-enhanced MRI venography appears feasible for non-invasive pre-interventional assessment of the course of the CS and its major tributaries. (orig.)

  16. Quantification of the effect of water exchange in dynamic contrast MRI perfusion measurements in the brain and heart

    DEFF Research Database (Denmark)

    Larsson, H B; Rosenbaum, S; Fritz-Hansen, T

    2001-01-01

    Measurement of myocardial and brain perfusion when using exogenous contrast agents (CAs) such as gadolinium-DTPA (Gd-DTPA) and MRI is affected by the diffusion of water between compartments. This water exchange may have an impact on signal enhancement, or, equivalently, on the longitudinal...... exchange can have a significant effect on perfusion estimation (F) in the brain when using Gd-DTPA, where it acts as an intravascular contrast agent....

  17. Human pharmacokinetics of iohexol. A new nonionic contrast medium

    International Nuclear Information System (INIS)

    Olsson, B.; Aulie, A.; Sveen, K.; Andrew, E.

    1983-01-01

    The pharmacokinetics of iohexol, a new nonionic, water-soluble contrast medium, have been determined after intravenous injection in 20 healthy volunteers, at four different dose levels (125-500 mg I/kg). The apparent volume of distribution was 0.27 1/kg, indicating distribution in the extracellular water. The biologic half-life was 121 minutes, comparable with that of other intravascular contrast media. Iohexol was excreted completely unmetabolized in the urine, with a 100% recovery 24 hours after injection. A comparison of iohexol and chromium-51 ( 51 Cr)-EDTA clearances indicates that iohexol is mainly excreted by glomerular filtration. The 51 Cr-EDTA clearance was the same when injected separately and concomitantly with iohexol, indicating that glomerular filtration rate is not affected by iohexol. No dose dependency was observed in the investigated parameters t1/2 alpha, t1/2 beta, Vd, ClT or ClR. Iohexol pharmacokinetics are in correspondence with previously reported data on intravascular contrast media

  18. Impact of intravascular enhancement, heart rate, and calcium score on diagnostic accuracy in multislice Computed Tomography coronary angiography

    International Nuclear Information System (INIS)

    Cademartiri, Filippo; Mollet, Nico R.; Kriestin, Gabriel P.; Runza, Giuseppe; Bartolotta, Tommaso Vincenzo; Galia, Massimo; Midiri, Massimo; Belgrano, Manuel; Pozzi Mucelli, Roberto

    2005-01-01

    Purpose. To assess the effect of intravascular enhancement, heart rate, and calcium score on diagnostic accuracy in the detection of significant coronary artery stenosis using 16-row multislice computed tomography (MSCT). Materials and methods. One hundred patients (88 males; 59±11 years) with suspected coronary artery disease who had undergone conventional coronary angiography (CA) and MSCT-CA were retrospectively enrolled for the study. Patients underwent a MSCT-CA, with the following protocol: collimation 16x0.75 mm, gantry rotation time 420 ms, feed/rotation 2.8 mm, kV 120, mAs 400-500. The protocol for contrast material administration was 100 ml of Iodixanol 320 mgI/nl at 4 ml/s and the scan delay was defined with a bolus tracking technique. In all patients vascular enhancement was measured in the aortic root, and the left and the right coronary arteries. The average enhancement was used to divide the population in two groups of 50 patients each, one with lower enhancement (Low), and one with higher enhancement (High). In the two groups diagnostic accuracy (per coronary segment) for the detection of significant stenosis (≥50% lumen reduction) was evaluated in vessels ≥2mm in diameter using quantitative CA as the reference standard. The differences in diagnostic accuracy were compared with a Chi-square test and a p [it

  19. A new method to measure necrotic core and calcium content in coronary plaques using intravascular ultrasound radiofrequency-based analysis

    NARCIS (Netherlands)

    E.S. Shin (Eun-Seok); H.M. Garcia-Garcia (Hector); P.W.J.C. Serruys (Patrick)

    2010-01-01

    textabstractAlthough previous intravascular ultrasound (IVUS) radiofrequency-based analysis data showed acceptable reproducibility for plaque composition, measurements are not easily obtained, particularly that of lumen contour, because of the limited IVUS resolution. The purpose of this study was

  20. Perfusion imaging with magnetic-susceptibility contrast media

    International Nuclear Information System (INIS)

    Rosen, B.R.; Belliveau, J.W.; Betteridge, D.; Cohen, M.S.; Weisskoff, R.M.; Vevea, J.M.; Rzedzian, R.P.; Brady, T.J.

    1989-01-01

    In animal models, transient signal los on T2-weighted images has been well documented following intravenous injection of high-magnetic-susceptibility contrast agents that are compartmentalized within the brain intravascular space. These signal changes have been correlated with physiologic parameters, such as blood flow and volume. The advent of whole-body single-shot imaging capability, coupled with the approval of paramagnetic contrasts agents for human use, has enabled the authors to demonstrate susceptibility contrast in the human brain, allowing for generation of functional images. With use of a 1.5-T imaging system gradient-echo images (TE = 60 msec) were acquired in 75 msec. Sequential single-sections images were sampled every 1 second following bolus administration of 0.1 mmol/kg of Gd-DTPA

  1. P-shaped Coiled Stator Ultrasound Motor for Rotating Intravascular Surgery Device

    Directory of Open Access Journals (Sweden)

    Toshinobu ABE

    2015-01-01

    Full Text Available The primary focus of this paper is the development of an ultra-miniature ultrasound motor for use in the human blood vessel. Since the size of the drive source for rotating the atherectomy device and intravascular ultrasonography system are large currently in practical use, it is installed outside the body, and the rotational power for the atherectomy device and intravascular ultrasonography system are transmitted through the long tortuous blood vessel. Such systems suffer from the problem that the rotation becomes non-uniform, and the problem that the available time is limited. We have therefore developed a P-shaped coiled stator ultrasound motor as a miniature ultrasound motor for rotating the ultrasound sensor for use in blood vessels in order to solve these problems. In this paper, we describe measurement of the torque, revolution speed, output power, efficiency, and particle motion on acoustic waveguide of the P-shaped coiled stator ultrasound motor.

  2. Intravascular versus surface cooling for targeted temperature management after out-of-hospital cardiac arrest

    DEFF Research Database (Denmark)

    Glover, Guy W; Thomas, Richard M; Vamvakas, George

    2016-01-01

    , maintenance and rewarming phases in addition to adverse events. All-cause mortality, as well as a composite of poor neurological function or death, as evaluated by the Cerebral Performance Category and modified Rankin scale were analysed. RESULTS: For patients managed at 33 °C there was no difference between......BACKGROUND: Targeted temperature management is recommended after out-of-hospital cardiac arrest and may be achieved using a variety of cooling devices. This study was conducted to explore the performance and outcomes for intravascular versus surface devices for targeted temperature management after...... out-of-hospital cardiac arrest. METHOD: A retrospective analysis of data from the Targeted Temperature Management trial. N = 934. A total of 240 patients (26%) managed with intravascular versus 694 (74%) with surface devices. Devices were assessed for speed and precision during the induction...

  3. Transbiliary intravascular ultrasound-guided diagnostic biopsy of an inaccessible pancreatic head mass

    Directory of Open Access Journals (Sweden)

    Jeffrey Forris Beecham Chick, MD, MPH, DABR

    2017-06-01

    Full Text Available Percutaneous image-guided biopsies of pancreatic malignancies may prove challenging and nondiagnostic due to a variety of anatomic considerations. For patients with complex post-surgical anatomy, such as a Roux-en-Y gastric bypass, diagnosis via endoscopic ultrasound with fine-needle aspiration may not be possible because of an inability to reach the proximal duodenum. This report describes the first diagnostic case of transbiliary intravascular ultrasound-guided biopsy of a pancreatic head mass in a patient with prior Roux-en-Y gastric bypass for which a diagnosis could not be achieved via percutaneous and endoscopic approaches. Transbiliary intravascular ultrasound-guided biopsy resulted in a diagnosis of pancreatic adenocarcinoma, allowing the initiation of chemotherapy.

  4. Intravascular Papillary Endothelial Hyperplasia Associated with Venous Pool Arising in the Lower Lip: A Case Report

    Directory of Open Access Journals (Sweden)

    Hisanobu Yonezawa

    2009-01-01

    Full Text Available Intravascular papillary endothelial hyperplasia is a benign nonneoplastic vascular lesion that consists of endothelial cells with abundant vascular tissue with papillary proliferation. An adult female had a painless growing dark red nodule on the left side of the lower lip and often touched and gnawed at it for more than 4 years. The lesion was a tender, smooth mass approximately 1 cm in diameter without discoloration reaction. Magnetic resonance imaging of the lesion showed specific findings. She was diagnosed clinically as having mimicked hemangioma, and the lesion was totally excised under local anesthesia. Histopathological examination revealed that papillary proliferated endothelial cells with venous pool, and the lesion was diagnosed as intravascular papillary endothelial hyperplasia associated with venous pool. There has been no recurrence for more than 1 year. Despite the benign nature of this lesion, it could have been mistaken for a malignant tumor because of its clinical course and radiologic findings.

  5. Effect of catecholamines and insulin on plasma volume and intravascular mass of albumin in man

    DEFF Research Database (Denmark)

    Hilsted, J; Christensen, N J; Larsen, S

    1989-01-01

    1. The effect of intravenous catecholamine infusions and of intravenous insulin on plasma volume and intravascular mass of albumin was investigated in healthy males. 2. Physiological doses of adrenaline (0.5 microgram/min and 3 microgram/min) increased peripheral venous packed cell volume...... significantly; intravenous noradrenaline at 0.5 microgram/min had no effect on packed cell volume, whereas packed cell volume increased significantly at 3 micrograms of noradrenaline/min. No significant change in packed cell volume was found during saline infusion. 3. During adrenaline infusion at 6 micrograms...... in packed cell volume, plasma volume, intravascular mass of albumin and transcapillary escape rate of albumin during hypoglycaemia may be explained by the combined actions of adrenaline and insulin....

  6. MRI evaluation and follow-up of bone necrosis after meningococcal infection and disseminated intravascular coagulation

    International Nuclear Information System (INIS)

    Damry, N.; Schurmans, T.; Perlmutter, N.

    1993-01-01

    Disseminated intravascular coagulation (DIC) is a serious complication of meningococcal septicaemia. It often results in infarction of various tissues namely the skin, adrenal glands, kidneys, brain and, much less commonly, bones. We describe a patient who presented bone lesions after meningococcal septicaemia. In addition to plain radiography and scintigraphy the lesions were evaluated with MRI and have proved to be extensive and still progressive, approxximately 18 months after the onset of the disease. (orig.)

  7. Novel Double-Needle System That Can Prevent Intravascular Injection of Any Filler

    Directory of Open Access Journals (Sweden)

    Hsiang Huang, MD

    2017-09-01

    Full Text Available Summary:. A new type of needle system combines 2 parts, an inner needle and an outer needle. The inner needle is used for filler injection and the outer needle acts as a guiding needle that can observe blood reflow when inserting into the vessel lumen during injection process. This new needle system can be used for all kinds of filler, providing real time monitoring for physician and preventing intravascular injection of any filler.

  8. Distribution of [35S] taurine in mouse retina after intravitreal and intravascular injection

    International Nuclear Information System (INIS)

    Pourcho, R.G.

    1977-01-01

    The distribution of [ 35 S] taurine in mouse retinae was studied by autoradiographic techniques after either intravitreal or intravascular injection. The route of injection did not affect the final localization. The major sites of label accumulation were the outer nuclear layer, the inner nuclear layer, and Mueller cell processes adjacent to the vitreal surface. The distribution was consistent with the interpretation that taurine was localized within two cellular compartments of mouse retina, photoreceptor cells and Mueller cells. (author)

  9. Association of insulin resistance and coronary artery remodeling: an intravascular ultrasound study

    OpenAIRE

    Kim, Sang-Hoon; Moon, Jae-Youn; Lim, Yeong Min; Kim, Kyung Ho; Yang, Woo-In; Sung, Jung-Hoon; Yoo, Seung Min; Kim, In Jai; Lim, Sang-Wook; Cha, Dong-Hun; Cho, Seung-Yun

    2015-01-01

    Background There are few studies that investigated the correlation between insulin resistance (IR) and the coronary artery remodeling. The aim of the study is to investigate the association of IR measured by homeostasis model assessment of insulin resistance (HOMA-IR) and coronary artery remodeling evaluated by intravascular ultrasound (IVUS). Methods A total of 298 consecutive patients who received percutaneous coronary interventions under IVUS guidance were retrospectively enrolled. The val...

  10. Conceptual source design and dosimetric feasibility study for intravascular treatment: a proposal for intensity modulated brachytherapy

    International Nuclear Information System (INIS)

    Kim, Si Yong; Han, Eun Young; Palta, Jatinder R.; Ha, Sung W.

    2003-01-01

    To propose a conceptual design of a novel source for intensity modulated brachytherapy. The source design incorporates both radioactive and shielding materials (stainless steel or tungsten), to provide an asymmetric dose intensity in the azimuthal direction. The intensity modulated intravascular brachytherapy was performed by combining a series of dwell positions and times, distributed along the azimuthal coordinates. Two simple designs for the beta-emitting sources, with similar physical dimensions to a 90 Sr/Y Novoste Beat-Cath source, were considered in the dosimetric feasibility study. In the first design, the radioactive and materials each occupy half of the cylinder and in the second, the radioactive material occupies only a quarter of the cylinder. The radial and azimuthal dose distributions around each source were calculated using the MCNP Monte Carlo code. The preliminary hypothetical simulation and optimization results demonstrated the 87% difference between the maximum and minimum doses to the lumen wall, due to off-centering of the radiation source, could be reduced to less than 7% by optimizing the azimuthal dwell positions and times of the partially shielded intravascular brachytherapy sources. The novel brachytherapy source design, and conceptual source delivery system, proposed in this study show promising dosimetric characteristics for the realization of intensity modulated brachytherapy in intravascular treatment. Further development of this concept will center on building a delivery system that can precisely control the angular motion of a radiation source in a small-diameter catheter

  11. Evaluation of CT virtual intravascular endoscopy in fenestrated stent grafts: a preliminary study

    International Nuclear Information System (INIS)

    Sun, Z.; Allen, Y.; Fitzsimmons, B.; Hartely, D.; Lawrence-Brown, M.

    2007-01-01

    We aim in this study to investigate the potential value of CT virtual intravascular endoscopy in patients diagnosed with abdominal aortic aneurysms undergoing fenestrated stent grafts. Both pre-and post-fenestration (within 3 months of implantation) multislice CT data were collected in eight patients and used for generation of virtual endoscopy images in our preliminary study. Variable fenestrations were deployed in 25 aortic branches with scallop fenestration implanted in six aortic ostia, large fenestration in four aortic ostia and small fenestration in 15 renal ostia, respectively. Measurements of the aortic ostia diameters both pre- and post-fenestration were successfully performed with virtual intravascular endoscopy visualization, and endovascular stents as well as their relationship to the aortic ostia were clearly demonstrated. Our results showed that there was no significant change of diameter of the aortic ostia following fenestrated stem grafts. Endovascular stents were clearly visualized on virtual endoscopy images, and no apparent deformity or malrotation was observed in this small group. Our preliminary study provides new insights into anatomic configuration/dimension of aortic ostia and endovascular stents, and virtual intravascular endoscopy could be a valuable technique to follow-up patients treated with fenestrated stent grafts. (orig.)

  12. Evaluation of CT virtual intravascular endoscopy in fenestrated stent grafts: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z. [Dept. of Imaging and Applied Physics, Curtin Univ. of Tech., Perth, WA (Australia); Allen, Y.; Fitzsimmons, B.; Hartely, D. [Cook R and D, WA (Australia); Lawrence-Brown, M. [Dept. of Public Health, Curtin Univ. of Tech., Perth, WA (Australia)

    2007-06-15

    We aim in this study to investigate the potential value of CT virtual intravascular endoscopy in patients diagnosed with abdominal aortic aneurysms undergoing fenestrated stent grafts. Both pre-and post-fenestration (within 3 months of implantation) multislice CT data were collected in eight patients and used for generation of virtual endoscopy images in our preliminary study. Variable fenestrations were deployed in 25 aortic branches with scallop fenestration implanted in six aortic ostia, large fenestration in four aortic ostia and small fenestration in 15 renal ostia, respectively. Measurements of the aortic ostia diameters both pre- and post-fenestration were successfully performed with virtual intravascular endoscopy visualization, and endovascular stents as well as their relationship to the aortic ostia were clearly demonstrated. Our results showed that there was no significant change of diameter of the aortic ostia following fenestrated stem grafts. Endovascular stents were clearly visualized on virtual endoscopy images, and no apparent deformity or malrotation was observed in this small group. Our preliminary study provides new insights into anatomic configuration/dimension of aortic ostia and endovascular stents, and virtual intravascular endoscopy could be a valuable technique to follow-up patients treated with fenestrated stent grafts. (orig.)

  13. Disseminated intravascular coagulation caused by moojenactivase, a procoagulant snake venom metalloprotease.

    Science.gov (United States)

    Sartim, Marco A; Cezarette, Gabriel N; Jacob-Ferreira, Anna L; Frantz, Fabiani G; Faccioli, Lucia H; Sampaio, Suely V

    2017-10-01

    Snake venom toxins that activate coagulation factors are key players in the process of venom-induced coagulopathy, and account for severe clinical manifestations. The present study applies a variety of biochemical, hematological, and histopathological approaches to broadly investigate the intravascular and systemic effects of moojenactivase (MooA), the first described PIIId subclass metalloprotease isolated from Bothrops sp. venom that activates coagulation factors. MooA induced consumption coagulopathy with high toxic potency, characterized by prolongation of prothrombin and activated partial thromboplastin time, consumption of fibrinogen and the plasma coagulation factors X and II, and thrombocytopenia. MooA promoted leukocytosis and expression of the proinflammatory cytokines interleukin-6 and tumor necrosis factor-α, accompanied by tissue factor-dependent procoagulant activity in peripheral blood mononuclear cells. This metalloprotease also caused intravascular hemolysis, elevated plasma levels of creatine kinase-MB, aspartate transaminase, and urea/creatinine, and induced morphopathological alterations in erythrocytes, heart, kidney, and lungs associated with thrombosis and hemorrhage. Diagnosis of MooA-induced disseminated intravascular coagulation represents an important approach to better understand the pathophysiology of Bothrops envenomation and develop novel therapeutic strategies targeting hemostatic disturbances. Copyright © 2017. Published by Elsevier B.V.

  14. Cardiovascular disease in haemodialysis: role of the intravascular innate immune system.

    Science.gov (United States)

    Ekdahl, Kristina N; Soveri, Inga; Hilborn, Jöns; Fellström, Bengt; Nilsson, Bo

    2017-05-01

    Haemodialysis is a life-saving renal replacement modality for end-stage renal disease, but this therapy also represents a major challenge to the intravascular innate immune system, which is comprised of the complement, contact and coagulation systems. Chronic inflammation is strongly associated with cardiovascular disease (CVD) in patients on haemodialysis. Biomaterial-induced contact activation of proteins within the plasma cascade systems occurs during haemodialysis and initially leads to local generation of inflammatory mediators on the biomaterial surface. The inflammation is spread by soluble activation products and mediators that are generated during haemodialysis and transported in the extracorporeal circuit back into the patient together with activated leukocytes and platelets. The combined effect is activation of the endothelium of the cardiovascular system, which loses its anti-thrombotic and anti-inflammatory properties, leading to atherogenesis and arteriosclerosis. This concept suggests that maximum suppression of the intravascular innate immune system is needed to minimize the risk of CVD in patients on haemodialysis. A potential approach to achieve this goal is to treat patients with broad-specificity systemic drugs that target more than one of the intravascular cascade systems. Alternatively, 'stealth' biomaterials that cause minimal cascade system activation could be used in haemodialysis circuits.

  15. Intravascular pulmonary metastases from sarcoma: appearance on computed tomography in 3 cases

    International Nuclear Information System (INIS)

    Ting, P.T.; Burrowes, P.W.; Gray, R.R.

    2005-01-01

    Various common malignant neoplasms (ie, liver, kidney, stomach and breast) have been reported to embolize to the pulmonary arterial system. This uncommon occurrence can also result from metastatic sarcoma. We report 3 cases- 2 chondrosarcomas and 1 osteosarcoma-associated with intravascular motastases to the pulmonary vasculature and discuss the clinical presentation and differentiating radiologic features on computed tomography (CT). Intravascular pulmonary tumour emboli may present with nonspecific respiratory symptoms or remain completely asymptomatic, and therefore, many patients are often misdiagnosed with thromboembolic disease or undiagnosed until autopsy. Chest CTs in all our patients demonstrated a striking pattern of multifocal tubular branching beaded opacities along the pulmonary vasculature in a multilobular distribution. Our observations and a review of the literature indicate that chest CT is the most useful diagnostic tool for detecting intravascular pulmonary tumour emboli. CT can distinguish this entity from mucous plugging by demonstrating the normal adjacent bronchus. The tubular nature of these metastases distinguishes them from the more common parenchymal metastases. (author)

  16. The lateral neostriatum is necessary for compensatory ingestive behaviour after intravascular dehydration in female rats.

    Science.gov (United States)

    Lelos, M J; Harrison, D J; Rosser, A E; Dunnett, S B

    2013-12-01

    Aberrant striatal function results in an array of physiological symptoms, including impaired consummatory and regulatory behaviours, which can lead to weight loss and dehydration. It was hypothesised, therefore, that cell loss in the neostriatum may contribute to altered fluid intake by regulating physiological signals related to dehydration status. To test this theory, rats with lesions of the lateral neostriatum and sham controls underwent a series of physiological challenges, including the experimental induction of intracellular and intravascular dehydration. No baseline differences in prandial or non-prandial drinking were observed, nor were differences in locomotor activity evident between groups. Furthermore, intracellular dehydration increased water intake in lesion rats in a manner comparable to sham rats. Interestingly, a specific impairment was evident in lesion rats after subcutaneous injection of poly-ethylene glycol was used to induce intravascular dehydration, such that lesion rats failed to adapt their water intake to this physiological change. The results suggest that the striatal lesions resulted in regulatory dysfunction by impairing motivational control over compensatory ingestive behaviour after intravascular hydration, while the physiological signals related to dehydration remain intact. Loss of these cells in neurodegenerative disorders, such Huntington's disease, may contribute to regulatory changes evident in the course of the disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Conceptual source design and dosimetric feasibility study for intravascular treatment: a proposal for intensity modulated brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Si Yong; Han, Eun Young; Palta, Jatinder R. [College of Medicine, Florida Univ., Florida (United States); Ha, Sung W. [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2003-06-01

    To propose a conceptual design of a novel source for intensity modulated brachytherapy. The source design incorporates both radioactive and shielding materials (stainless steel or tungsten), to provide an asymmetric dose intensity in the azimuthal direction. The intensity modulated intravascular brachytherapy was performed by combining a series of dwell positions and times, distributed along the azimuthal coordinates. Two simple designs for the beta-emitting sources, with similar physical dimensions to a {sub 90}Sr/Y Novoste Beat-Cath source, were considered in the dosimetric feasibility study. In the first design, the radioactive and materials each occupy half of the cylinder and in the second, the radioactive material occupies only a quarter of the cylinder. The radial and azimuthal dose distributions around each source were calculated using the MCNP Monte Carlo code. The preliminary hypothetical simulation and optimization results demonstrated the 87% difference between the maximum and minimum doses to the lumen wall, due to off-centering of the radiation source, could be reduced to less than 7% by optimizing the azimuthal dwell positions and times of the partially shielded intravascular brachytherapy sources. The novel brachytherapy source design, and conceptual source delivery system, proposed in this study show promising dosimetric characteristics for the realization of intensity modulated brachytherapy in intravascular treatment. Further development of this concept will center on building a delivery system that can precisely control the angular motion of a radiation source in a small-diameter catheter.

  18. Pulsed arterial spin labeling using TurboFLASH with suppression of intravascular signal.

    Science.gov (United States)

    Pell, Gaby S; Lewis, David P; Branch, Craig A

    2003-02-01

    Accurate quantification of perfusion with the ADC techniques requires the suppression of the majority of the intravascular signal. This is normally achieved with the use of diffusion gradients. The TurboFLASH sequence with its ultrashort repetition times is not readily amenable to this scheme. This report demonstrates the implementation of a modified TurboFLASH sequence for FAIR imaging. Intravascular suppression is achieved with a modified preparation period that includes a driven equilibrium Fourier transform (DEFT) combination of 90 degrees-180 degrees-90 degrees hard RF pulses subsequent to the inversion delay. These pulses rotate the perfusion-prepared magnetization into the transverse plane where it can experience the suitably placed diffusion gradients before being returned to the longitudinal direction by the second 90 degrees pulse. A value of b = 20-30 s/mm(2) was thereby found to suppress the majority of the intravascular signal. For single-slice perfusion imaging, quantification is only slightly modified. The technique can be readily extended to multislice acquisition if the evolving flow signal after the DEFT preparation is considered. An advantage of the modified preparation scheme is evident in the multislice FAIR images by the preservation of the sign of the magnetization difference. Copyright 2003 Wiley-Liss, Inc.

  19. An experimental method for detecting blood splatter from retractable phlebotomy and intravascular devices.

    Science.gov (United States)

    Haiduven, Donna; Applegarth, Shawn; Shroff, Miloni

    2009-03-01

    This study was designed to evaluate the safety of retractable intravascular devices in terms of their potential to produce blood splatter. A method for measuring this blood splatter designed by the research team was used to evaluate 3 specific intravascular devices. Scientific filters were positioned around the retraction mechanisms of the devices and weighed with an analytical scale, both before and after activation, in a simulated vein containing mock venous blood. The difference in filter mass was used as the primary unit of analysis to detect blood splatter. In addition, the filters were visually inspected for the presence or absence of blood. A paired t-test revealed significant differences in the prefilter and postfilter groups for 2 of the 3 devices tested (P blood was detected on 23% to 40% of the scientific filters for 2 of the devices. Our findings indicate a potential for bloodborne pathogen exposure with the use of intravascular devices with a retractable mechanism. This experiment may serve as a model in the design and implementation of future sharps device evaluation protocols to validate the threat of bloodborne pathogen exposure.

  20. Hydrophilic Polymer Embolism: Implications for Manufacturing, Regulation, and Postmarket Surveillance of Coated Intravascular Medical Devices.

    Science.gov (United States)

    Mehta, Rashi I; Mehta, Rupal I

    2018-03-19

    Hydrophilic polymers are ubiquitously applied as surface coatings on catheters and intravascular medical technologies. Recent clinical literature has heightened awareness on the complication of hydrophilic polymer embolism, the phenomenon wherein polymer coating layers separate from catheter and device surfaces, and may be affiliated with a range of unanticipated adverse reactions. Significant system barriers have limited and delayed reporting on this iatrogenic complication, the full effects of which remain underrecognized by healthcare providers and manufacturers of various branded devices. In 2015, the United States Food and Drug Administration acknowledged rising clinical concerns and stated that the agency would work with stakeholders to further evaluate gaps that exist in current national and international device standards for coated intravascular medical technologies. The present article reviews current knowledge on this complication as well as factors that played a role in delaying detection and dissemination of information and new knowledge once hazards and clinical risks were identified. Furthermore, organ-specific effects and adverse reaction patterns are summarized, along with implications for device manufacturing, safety assurance, and regulation. Qualitative and quantitative particulate testing are needed to optimize coated intravascular device technologies. Moreover, general enhanced processes for medical device surveillance are required for timely adverse event management and to ensure patient safety.

  1. Nanodiamond-Manganese dual mode MRI contrast agents for enhanced liver tumor detection.

    Science.gov (United States)

    Hou, Weixin; Toh, Tan Boon; Abdullah, Lissa Nurrul; Yvonne, Tay Wei Zheng; Lee, Kuan J; Guenther, Ilonka; Chow, Edward Kai-Hua

    2017-04-01

    Contrast agent-enhanced magnetic resonance (MR) imaging is critical for the diagnosis and monitoring of a number of diseases, including cancer. Certain clinical applications, including the detection of liver tumors, rely on both T1 and T2-weighted images even though contrast agent-enhanced MR imaging is not always reliable. Thus, there is a need for improved dual mode contrast agents with enhanced sensitivity. We report the development of a nanodiamond-manganese dual mode contrast agent that enhanced both T1 and T2-weighted MR imaging. Conjugation of manganese to nanodiamonds resulted in improved longitudinal and transverse relaxivity efficacy over unmodified MnCl 2 as well as clinical contrast agents. Following intravenous administration, nanodiamond-manganese complexes outperformed current clinical contrast agents in an orthotopic liver cancer mouse model while also reducing blood serum concentration of toxic free Mn 2+ ions. Thus, nanodiamond-manganese complexes may serve as more effective dual mode MRI contrast agent, particularly in cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Effects of iodinated contrast media on blood and endothelium

    International Nuclear Information System (INIS)

    Aspelin, Peter; Stacul, Fulvio; Thomsen, Henrik S.; Morcos, Sameh K.; Molen, Aart J. van der

    2006-01-01

    The aim of the study was to assess the effects of iodinated contrast media on blood components and endothelium based on experimental and clinical studies and to produce clinically relevant guidelines for reducing thrombotic and hematologic complications following the intravascular use of contrast media. A report was drafted after review of the literature and discussions among the members of the Contrast Media Safety Committee of the European Society of Urogenital Radiology. The final report was produced following discussion at the 12th European Symposium on Urogenital Radiology in Ljubljana, Slovenia (2005). Experimental data indicate that all iodinated contrast media produce an anticoagulant effect and that this effect is greater with ionic contrast media. Several of the in vitro and experimental in vivo studies on haematological effects of contrast media have not been confirmed by clinical studies. Low- or iso-osmolar contrast media should be used for diagnostic and interventional angiographic procedures, including phlebography. Meticulous angiographic technique is the most important factor for reducing the thrombotic complications associated with angiographic procedures. Drugs and interventional devices that decrease the risk of thromboembolic complications during interventional procedures minimize the importance of the effects of contrast media. (orig.)

  3. Effects of iodinated contrast media on blood and endothelium

    Energy Technology Data Exchange (ETDEWEB)

    Aspelin, Peter [Karolinska Institute/Huddinge University Hospital, Division of Radiology, Centre for Surgical Sciences, Stockholm (Sweden); Stacul, Fulvio [Institute of Radiology, Trieste (Italy); Thomsen, Henrik S. [Copenhagen University Hospital at Herlev, Department of Diagnostic Radiology 54E2, Herlev (Denmark); Morcos, Sameh K. [Sheffield Teaching Hospitals NHS Trust, Department of Diagnostic Imaging, Northern General Hospital, Sheffield (United Kingdom); Molen, Aart J. van der [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands)

    2006-05-15

    The aim of the study was to assess the effects of iodinated contrast media on blood components and endothelium based on experimental and clinical studies and to produce clinically relevant guidelines for reducing thrombotic and hematologic complications following the intravascular use of contrast media. A report was drafted after review of the literature and discussions among the members of the Contrast Media Safety Committee of the European Society of Urogenital Radiology. The final report was produced following discussion at the 12th European Symposium on Urogenital Radiology in Ljubljana, Slovenia (2005). Experimental data indicate that all iodinated contrast media produce an anticoagulant effect and that this effect is greater with ionic contrast media. Several of the in vitro and experimental in vivo studies on haematological effects of contrast media have not been confirmed by clinical studies. Low- or iso-osmolar contrast media should be used for diagnostic and interventional angiographic procedures, including phlebography. Meticulous angiographic technique is the most important factor for reducing the thrombotic complications associated with angiographic procedures. Drugs and interventional devices that decrease the risk of thromboembolic complications during interventional procedures minimize the importance of the effects of contrast media. (orig.)

  4. The fluoro-less and contrast-less peripheral endovascular intervention: Halfway there

    Energy Technology Data Exchange (ETDEWEB)

    Ephrem, Georges, E-mail: g.ephrem@gmail.com; Garikipati, Sireesha; Hanson, Ivan D.

    2016-09-15

    Introduction: Percutaneous endovascular revascularization requires the use of fluoroscopic guidance and radiopaque contrast. We present a successful intervention without the use of iodinated contrast. Case: A 92-year-old man with dry gangrene involving the second and fourth left toes had acute on chronic kidney injury. Arterial duplex showed severe stenosis in bilateral superficial femoral arteries (SFAs). Fluoroscopic and ultrasound guidance and intravascular imaging were used to avoid iodinated contrast. After right to left femoral crossover, the entire left SFA was imaged with ultrasound. The lesion was delineated with radiopaque measuring tapes then wired. Near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) imaging were performed. Points of interest were correlated with corresponding radiopaque markings on the ruler. Stenting and post-dilation resulted in complete stent expansion and no evidence of dissection by IVUS. The total procedure time was 113 min and the total radiation dose 813 mGy. The day after the procedure, there was a palpable dorsalis pedis pulse. He was discharged to inpatient rehabilitation on dual antiplatelet therapy. Discussion: Contrast and radiation continue to limit the feasibility of endovascular angiography and intervention. Carbon dioxide (CO2) digital subtraction angiography is an alternative for these patients but has several disadvantages. Previously proposed projects demonstrated the real potential of performing endovascular peripheral intervention without fluoroscopy or contrast. Conclusion: This case is a clear demonstration of a successful use of a combination of fluoroscopy, ultrasonography and intravascular imaging to achieve a successful endovascular intervention to treat critical limb ischemia, without the use of iodinated contrast.

  5. X-ray contrast media-an overview

    International Nuclear Information System (INIS)

    Christiansen, Cathrine

    2005-01-01

    X-ray contrast media are chemically inert drugs which are given intravascularly in very high amounts within a very short time period. Although they are regarded as relatively safe drugs, adverse reactions can occur: these are normally divided into immediate and delayed reactions. The latter appear hours to days after injection. Immediate reactions have been drastically reduced since the introduction of non-ionic monomers and non-ionic dimers. However, the delayed reactions still occur in a frequency of 1-3% in X-ray contrast media exposed patients. The majority of these reactions are mild and manifest as skin eruption, but severe reactions can also occur. Further improvement of the safety of these drugs is only possible with a better understanding of etiologies behind the observed adverse reactions

  6. Polymer coating embolism from intravascular medical devices - a clinical literature review.

    Science.gov (United States)

    Chopra, Amitabh M; Mehta, Monik; Bismuth, Jean; Shapiro, Maksim; Fishbein, Michael C; Bridges, Alina G; Vinters, Harry V

    Over the past three decades, lubricious (hydrophobic and/or hydrophilic) polymer-coated devices have been increasingly adopted by interventional physicians and vascular surgeons to access and treat a wider range of clinical presentations. Recent clinical literature highlights the presence of polymer coating emboli within the anatomy - a result of coating separation from an intravascular device - and associates it with a range of adverse clinical sequelae. The 2015 U.S. Food and Drug Administration safety communication titled "Lubricious Coating Separation from Intravascular Medical Devices" acknowledges these concerns and concludes that it will work with stakeholders to develop nonclinical test methodologies, establish performance criteria, and identify gaps in current national and international device standards for coating integrity performance. Despite this communication and multiple case reports from interventional physicians, pathologists, dermatologists and other involved physician specialties, polymer coating embolism remains clinically underrecognized. This article consolidates the available literature on polymer coating embolism (1986-2016) and highlights the following relevant information for the physician: (a) the history and elusive nature of polymer coating embolism; (b) potential incidence rates of this phenomenon; (c) reported histologic findings and clinical effects of polymer emboli in the anatomy; (d) the importance of the collaborative clinician-pathologist partnership to report polymer embolism findings; and (e) the importance to study particulate release from intravascular devices so as to further understand and potentially evolve coated interventional technologies. Preliminary research on coatings highlights the potential of using iterations of coatings on medical devices that attain the desired therapeutic result and mitigate or eliminate particulates altogether. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Management of subarachnoid hemorrhage classified grade V. Possibility of intravascular treatment

    Energy Technology Data Exchange (ETDEWEB)

    Uzura, Masahiko; Oshima, Kousuke; Morishima, Hiroyuki; Uchida, Kazuyoshi; Watanabe, Hiroyuki; Nakamura, Homare; Tanaka, Katsuyuki; Sekino, Hiroaki; Akashi, Katsuya [St. Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

    2001-10-01

    Management outcomes in poor-grade patients (World Federation of Neurological Surgeons Committee on a Universal Subarachnoid Hemorrhage Grading Scale Grade V) with ruptured cerebral aneurysms have historically been unsatisfactory. In the present study, we examined the possibility of intravascular treatment for ruptured aneurysm detected by 3-Dimensional CT angiography (3D-CTA) in poor-grade SAH patients. From April 1997 to July 2000, 3D-CTA was performed on 54 of 73 patients admitted with Grade V subarachnoid hemorrhage (SAH). Excluding 3 patients who underwent emergency surgery for ruptured aneurysms and intracerebral hematomas, CT findings from the remaining 51 patients were analyzed. The study included 23 men and 28 women, ranging in age from 28 to 91 with an average age of 63.6. The patients' initial scores on the Glasgow Coma Scale upon admission were 3 in 36 patients (including 19 patients who had undergone cardio-pulmonary arrest), 4 in 11 patients, 5 in 2 patients, and 6 in 2 patients. Ruptured aneurysms responsible for SAH were clearly delineated in 41 aneurysms from 39 patients, with 32 aneurysms in the anterior circulation and 9 in the posterior circulation. Patients with Glasgow Coma Scale of 4 or higher whose score did not progressively decrease for 12 hours after symptom onset were considered for intravascular treatment. In our study, 4 of 39 patients (10.3%) met these criteria. Glasgow Outcome Scale results were good recovery in 1 case, moderate disability in 1 case, severe disability in 1 case, and death in the remaining 48 cases. These results suggest that the management course for poor-grade (WFNS Grade V) SAH patients who retain brain stem reflexes contain the following: identification of aneurysms by 3D-CTA, maintenance of adequate sedation and external drainage to treat acute hydrocephalus, continued minimum 12-hour observation, monitoring levels of consciousness where possible, and consideration of aggressive therapy including

  8. Ischemia monitoring in off-pump coronary artery bypass surgery using intravascular near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Zerkowski Hans-Reinhard

    2006-05-01

    Full Text Available Abstract Background In off-pump coronary artery bypass surgery, manipulations on the beating heart can lead to transient interruptions of myocardial oxygen supply, which can generate an accumulation of oxygen-dependent metabolites in coronary venous blood. The objective of this study was to evaluate the reliability of intravascular near-infrared spectroscopy as a monitoring method to detect possible ischemic events in off-pump coronary artery bypass procedures. Methods In 15 elective patients undergoing off-pump myocardial revascularization, intravascular near-infrared spectroscopic analysis of coronary venous blood was performed. NIR signals were transferred through a fiberoptic catheter for signal emission and collection. For data analysis and processing, a miniature spectrophotometer with multivariate statistical package was used. Signal acquisition and analysis were performed before and after revascularization. Spectroscopic data were compared with hemodynamic parameters, electrocardiogram, transesophageal echocardiography and laboratory findings. Results A conversion to extracorporeal circulation was not necessary. The mean number of grafts per patient was 3.1 ± 0.6. An intraoperative myocardial ischemia was not evident, as indicated by electrocardiogram and transesophageal echocardiography. Continuous spectroscopic analysis showed reproducible absorption spectra of coronary sinus blood. Due to uneventful intraoperative courses, clear ischemia-related changes could be detected in none of the patients. Conclusion Our initial results show that intravascular near-infrared spectroscopy can reliably be used for an online intraoperative ischemia monitoring in off-pump coronary artery bypass surgery. However, the method has to be further evaluated and standardized to determine the role of spectroscopy in off-pump coronary artery bypass surgery.

  9. Rash, disseminated intravascular coagulation and legionella: Episode 10 and a rewind into the past

    Directory of Open Access Journals (Sweden)

    Prashanth M. Thalanayar

    2015-01-01

    Full Text Available Legionella pneumophila is the most common cause of legionellosis and is one of the organisms causing atypical pneumonia. We report the presentation of disseminated intravascular coagulation (DIC and skin rash in a single case of severe Legionella pneumonia. The unique clinical presentation of a diffuse rash diagnosed as purpura fulminans and the unpredictable variations encountered during the diagnostic work-up of the case make this write-up crucial. This article synthesizes all reported cases of L. pneumonia associated with cutaneous manifestations as well as cases presenting with DIC. Furthermore, this manuscript illustrates the correlation between cutaneous and coagulopathic manifestations, and morbidity and mortality from L. pneumonia.

  10. Fatal Klebsiella pneumoniae meningitis and concomitant disseminated intravascular coagulation in a patient with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Ho Min-Po

    2009-01-01

    Full Text Available Bacterial meningitis remains a major cause of death and long-term neurologic sequelae worldwide. We present a case of fatal Klebsiella pneumoniae meningitis and concomitant disseminated intravascular coagulation (DIC in a 72-year-old woman with diabetes mellitus (DM. Both blood and cerebrospinal fluid cultures grew Klebsiella pneumoniae . Due to advanced age, newly recognized DM, K. pneumoniae bacteremia, and DIC, the prognosis of our patient was poor. Eight hours after arrival to the emergency department, cardiopulmonary resuscitation was necessary in this patient, but she died despite an early diagnosis and appropriate antibiotic therapy.

  11. Acute kidney injury and disseminated intravascular coagulation due to mercuric chloride poisoning

    Directory of Open Access Journals (Sweden)

    J Dhanapriya

    2016-01-01

    Full Text Available Mercury is a toxic heavy metal and occurs in organic and inorganic forms. Inorganic mercury includes elemental mercury and mercury salts. Mercury salts are usually white powder or crystals, and widely used in indigenous medicines and folk remedies in Asia. Inorganic mercury poisoning causes acute kidney injury (AKI and gastrointestinal manifestations and can be life-threatening. We describe a case with unknown substance poisoning who developed AKI and disseminated intravascular coagulation (DIC. Renal biopsy showed acute tubular necrosis. Later, the consumed substance was proven to be mercuric chloride. His renal failure improved over time, and his creatinine normalized after 2 months.

  12. Disseminated intravascular coagulation in a patient with metastatic prostate cancer: Fatal outcome following strontium-89 therapy

    Energy Technology Data Exchange (ETDEWEB)

    Leong, C.; McKenzie, R.; Coupland, D.B. [Univ. of British Columbia, (Canada)] [and others

    1994-10-01

    A patient with metastatic prostate cancer was found to have low-grade disseminated intravascular coagulation (DIC). He had significant bone pain despite external-beam radiotherapy and was given {sup 89}Sr with subsequent thrombocytopenia and epistaxis. The patient died from generalized hemorrhage 36 days postinjection. Although it is not possible to establish a causal relationship between {sup 89}Sr and DIC, practitioners should be alert to complications associated with the primary disorder which might occur at a time to raise concern about the intervention. 8 refs., 1 tab.

  13. [Intravascular Hemolysis Caused by Stenosis of an Elephant Trunk;Report of a Case].

    Science.gov (United States)

    Takamaru, Rikako; Kawahito, Koji; Aizawa, Kei; Misawa, Yoshio

    2017-07-01

    Symptomatic intravascular hemolysis after prosthetic aortic graft replacement is rare. It is primarily attributed to mechanical injury of red blood cells caused by stenosis of the vascular graft. A 50-year-old man presented with hemolytic anemia, 5 years after total arch replacement with an elephant trunk for type A aortic dissection. The hemolysis was caused by graft stenosis of the elephant trunk. Endovascular treatment for the stenotic elephant trunk was successfully performed. The postoperative course was uneventful, and the hemolysis was resolved immediately after operation.

  14. Intravascular Large B-Cell Lymphoma Presenting with Diffuse Gallbladder Wall Thickening: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Sayf Al-Katib

    2018-01-01

    Full Text Available Intravascular large B-cell lymphoma is a rare subtype of extranodal diffuse B-cell lymphoma characterized by proliferation of neoplastic cells within the lumen of small and medium sized vessels. Clinical and imaging findings are nebulous as the intravascular subtype of lymphoma can involve a multitude of organs. Involvement of the gallbladder is extremely uncommon, and imaging findings can be easily confused for more prevalent pathologies. We report a case of intravascular large B-cell lymphoma in an 83-year-old male and review clinical presentation and imaging findings on CT, ultrasound, hepatobiliary iminodiacetic acid (HIDA scan, and MRI. It is important for the radiologist to know about this disease as the imaging findings are atypical of other types of lymphoma, and this may lead to a delay in diagnosis and treatment.

  15. Combined hyponatremia and hypocalcemia after intravascular absorption of 1.5% glycine during operative hysteroscopy. A case report

    Directory of Open Access Journals (Sweden)

    Sherif S. Sultan

    2016-07-01

    Full Text Available Intravascular absorption of distending media may complicate operative hysteroscopy. Consequences differ according to type, amount and speed of absorption of the distending media. We report a case of intravascular absorption of more than one liter of 1.5% glycine. A 36 years old female developed metabolic acidosis, hyponatremia and hypocalcemia during operative hysteroscopy scheduled for resection of a uterine fibroid. Serum sodium reached down to 119 mmol/l and ionized calcium to 0.898 mmol/l. Serial estimations of arterial blood gases and serum electrolytes were followed. Management was successful in preventing serious side effects. Meticulous monitoring of distending media input/output balance remains the cornerstone in prevention of intravascular absorption.

  16. Effects of Hypoxia on Erythrocyte Membrane Properties—Implications for Intravascular Hemolysis and Purinergic Control of Blood Flow

    Directory of Open Access Journals (Sweden)

    Ryszard Grygorczyk

    2017-12-01

    Full Text Available Intravascular hemolysis occurs in hereditary, acquired, and iatrogenic hemolytic conditions but it could be also a normal physiological process contributing to intercellular signaling. New evidence suggests that intravascular hemolysis and the associated release of adenosine triphosphate (ATP may be an important mechanism for in vivo local purinergic signaling and blood flow regulation during exercise and hypoxia. However, the mechanisms that modulate hypoxia-induced RBC membrane fragility remain unclear. Here, we provide an overview of the role of RBC ATP release in the regulation of vascular tone and prevailing assumptions on the putative release mechanisms. We show importance of intravascular hemolysis as a source of ATP for local purinergic regulation of blood flow and discuss processes that regulate membrane propensity to rupture under stress and hypoxia.

  17. Offline fusion of co-registered intravascular ultrasound and frequency domain optical coherence tomography images for the analysis of human atherosclerotic plaques

    DEFF Research Database (Denmark)

    Räber, Lorenz; Heo, Jung Ho; Radu, Maria D

    2012-01-01

    To demonstrate the feasibility and potential usefulness of an offline fusion of matched optical coherence tomography (OCT) and intravascular ultrasound (IVUS)/virtual histology (IVUS-VH) images.......To demonstrate the feasibility and potential usefulness of an offline fusion of matched optical coherence tomography (OCT) and intravascular ultrasound (IVUS)/virtual histology (IVUS-VH) images....

  18. Comparison of utility of blood cultures from intravascular catheters and peripheral veins: a systematic review and decision analysis.

    Science.gov (United States)

    Falagas, Matthew E; Kazantzi, Maria S; Bliziotis, Ioannis A

    2008-01-01

    Blood cultures are sometimes obtained from intravascular catheters for convenience. However, there is controversy regarding this practice. The authors compared the diagnostic test characteristics of blood cultures obtained from intravascular catheters and peripheral veins. Relevant studies for inclusion in this review were identified through PubMed (January 1970-October 2005) and the Cochrane Central Register of Controlled Trials. Studies that reported clear definitions of true bacteraemia were included in the analysis. Two reviewers independently extracted the data. Six studies were included in the analysis, providing data for 2677 pairs of blood cultures obtained from an intravascular catheter and a peripheral venipuncture. A culture obtained from an intravascular catheter was found to be a diagnostic test for bacteraemia with better sensitivity (OR 1.85, 95 % CI 1.14-2.99, fixed effects model) and better negative predictive value (almost with statistical significance) (OR 1.55, 95 % CI 0.999-2.39, fixed effects model) but with less specificity (OR 0.33, 95 % CI 0.18-0.59, random effects model) and lower positive predictive value (OR 0.41, 95 % CI 0.23-0.76, random effects model) compared to a culture taken by peripheral venipuncture. In a group of 1000 patients, eight additional patients with true bacteraemia would be identified and 59 falsely diagnosed as having bacteraemia by a blood culture obtained from an intravascular catheter compared to results of the peripheral blood culture. Given the consequences of undertreating patients with bacteraemia, the authors believe that, based on the available evidence, at least one blood culture should be obtained from the intravascular catheter.

  19. Technical aspects of contrast-enhanced magnetic resonance imaging of the breast: literature review

    International Nuclear Information System (INIS)

    Leopoldino, Denise de Deus; Gracio, Tatiana Schiller; D'Ippolito, Giuseppe; Bezerra, Alexandre Sergio de Araujo; Gracio, Tatiana Schiller

    2005-01-01

    With the advances in surface coil technology and the development of new imaging protocols in addition to the increase of the use of contrast agents, contrast enhanced magnetic resonance imaging (MRI) has emerged as a promising modality for detection, diagnosis and staging of breast cancer. Despite these advances, there are some unresolved issues, including no defined standard technique for contrast-enhanced breast MRI and no standard criteria of interpretation for the evaluation of such studies. In this article, we review the literature and discuss the general requirements and recommendations for contrast agent-enhanced breast MRI, including image interpretation criteria, MR equipment, dedicated radiofrequency coils, use of paramagnetic contrast agents, fat-suppression techniques, planes of acquisition, pulse sequence specifications and artifact sources. (author)

  20. Patient selection and preparation strategies for the use of contrast material in patients with chronic kidney disease

    DEFF Research Database (Denmark)

    Andersen, Poul Erik

    2012-01-01

    administration of iodinated contrast media can result in contrast-induced acute kidney injury and Gadolinium can induce nephrogenic systemic fibrosis (NSF). It is important to identify these high-risk patients by means of se-creatinine/e glomerular filtration rate. The indication for contrast examination should......The prevalence of chronic kidney disease and peripheral arterial disease is increasing. Thus, it is increasingly problematic to image these patients as the number of patients needing a vascular examination is increasing accordingly. In high-risk patients with impaired kidney function, intravascular...

  1. Acute Kidney Injury by Radiographic Contrast Media: Pathogenesis and Prevention

    Science.gov (United States)

    Faga, Teresa; Pisani, Antonio; Michael, Ashour

    2014-01-01

    It is well known that iodinated radiographic contrast media may cause kidney dysfunction, particularly in patients with preexisting renal impairment associated with diabetes. This dysfunction, when severe, will cause acute renal failure (ARF). We may define contrast-induced Acute Kidney Injury (AKI) as ARF occurring within 24–72 hrs after the intravascular injection of iodinated radiographic contrast media that cannot be attributed to other causes. The mechanisms underlying contrast media nephrotoxicity have not been fully elucidated and may be due to several factors, including renal ischaemia, particularly in the renal medulla, the formation of reactive oxygen species (ROS), reduction of nitric oxide (NO) production, and tubular epithelial and vascular endothelial injury. However, contrast-induced AKI can be prevented, but in order to do so, we need to know the risk factors. We have reviewed the risk factors for contrast-induced AKI and measures for its prevention, providing a long list of references enabling readers to deeply evaluate them both. PMID:25197639

  2. Combined hyponatremia and hypocalcemia after intravascular absorption of 1.5% glycine during operative hysteroscopy. A case report

    OpenAIRE

    Sherif S. Sultan

    2016-01-01

    Intravascular absorption of distending media may complicate operative hysteroscopy. Consequences differ according to type, amount and speed of absorption of the distending media. We report a case of intravascular absorption of more than one liter of 1.5% glycine. A 36 years old female developed metabolic acidosis, hyponatremia and hypocalcemia during operative hysteroscopy scheduled for resection of a uterine fibroid. Serum sodium reached down to 119 mmol/l and ionized calcium to 0.898 mmol/l...

  3. Development of contrast media

    International Nuclear Information System (INIS)

    Krause, W.

    1993-01-01

    Description of all contrast media (ionic and nonionic monomers, ionic and nonionic dimers) was presented. Chemotoxicity, osmolality and viscosity of some contrast agents were analyzed. The main adverse reactions to ionic and nonionic contrast media were described

  4. Development of sup 1 sup 9 sup 2 Ir radiation sources for intravascular irradiation

    CERN Document Server

    Kogure, H; Iwamoto, S; Iwata, K; Kawauchi, Y; Nagata, Y; Sorita, T; Suzuki, K

    2003-01-01

    Intravascular brachytherapy is a novel therapy for preventing the restenosis of coronary artery by use of low-dose irradiation. JAERI and Kyoto University have been developing sup 1 sup 9 sup 2 Ir radiation sources by the cooperative research project entitled as 'The research on safety and effectiveness of the intravascular brachytherapy for preventing restenosis of the coronary artery disease' since 1998. The radiation source was introduced into the stenosis through a catheter (a guide-tube to insert directly into vascular) to irradiate the diseased part. Ten sup 1 sup 9 sup 2 Ir seed sources (phi 0.4 mm x 2.5 mm) were positioned between nylon spacers (phi 0.3 mm x 1.0 mm) in a flexible covering tube and the tube was plugged with a core-wire; the tube was shrunk to fix the inside materials and the size is 0.46 mm in diameter and 3 m in length. The physically optimal design was determined to insert the radiation source easily into vascular and to get the dose uniformity in the diseased part. The production me...

  5. Intrauterine intravascular transfusion for fetal haemolytic anaemia: the Western Australian experience.

    Science.gov (United States)

    Newnham, J P; Phillips, J M; Stock, R

    1992-11-16

    To report the first four years' clinical experience with fetal intravascular blood transfusion for the treatment of fetal haemolytic anaemia in Western Australia. King Edward Memorial Hospital, Perth, which is the sole tertiary level perinatal centre in Western Australia with a referral base of approximately 25,000 pregnancies each year. Transfusion was by injection of packed cells from Rh-negative donors into the fetal umbilical vein near the site of insertion into the placenta. Fetal haemoglobin levels were measured before and after each transfusion. In most cases, the fetus was paralysed by intramuscular tubocurarine. Sixty intravenous transfusions were performed in 20 pregnancies. At the time of the initial transfusion, the mean haemoglobin level was 5.8 g/dL (range, 2.5-8.5 g/dL) and six fetuses had signs of hydrops. The case survival rate was 80% and the procedure survival rate was 93%. Three of the deaths occurred in the first five cases. Caesarean section was performed during two of the procedures, one because of bleeding from the cord puncture site and one because of tamponade of the umbilical vessels. Fetal intravascular transfusion is a highly effective treatment for fetal alloimmunisation and allows pregnancies to continue to term and to be delivered vaginally. However, the procedure may be difficult and requires a team approach with ready access to fetal monitoring and emergency caesarean section. Our results suggest that increasing experience of the team is a major factor in improved outcome.

  6. Pulmonary intravascular lymphoma detected by FDG PET-CT: a case report.

    Science.gov (United States)

    Kohan, A A; Paganini, L; Biedak, P; Arma, J I; Dalurzo, M C L; Garcia-Monaco, R D

    2013-01-01

    Intravascular lymphoma is a rare subtype of extranodal Non-Hodgkin's lymphoma. Its prognosis is poor in a high percentage of cases due to its insidious appearance and low clinical suspicion. Its diagnosis is usually only reached after an autopsy. It may affect different organs as a whole or only one organ. It is extremely rare that the lung is the only damaged organ. Its diagnosis depends of the clinician's suspicion and proper evaluation with imaging studies as well as correct selection of the organ to be biopsied. When detected on time, the treatment of choice is a combination of a series of chemotherapy associated to a monoclonal antibody (anti-CD20). We present the case of a male patient who underwent a positron emission tomography-computed tomography with 2-[F-18]-fluoro-2 deoxy-D-glucose (FDG) due to symptoms suggestive of a lymphoproliferative disease with no clear structural abnormalities. The images led to a diagnosis of pulmonary intravascular large B cell lymphoma. Copyright © 2012 Elsevier España, S.L. and SEMNIM. All rights reserved.

  7. Plasma volume, intravascular albumin and its transcapillary escape rate in patients with extensive skin disease

    DEFF Research Database (Denmark)

    Parving, H H; Worm, A M; Rossing, N

    1976-01-01

    Plasma volume and plasma concentration and transcapillary escape rate of albumin (TER alb), i.e. the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, were determined using 125I-labelled human albumin in eight patients with extensive skin disease....... Plasma volume and plasma albumin concentration were reduced (P less than 0-05). Thus the intravascular albumin mass was moderately decreased to an average of 0-55 +/- 0-06 (s.d.) g/cm height compared with a normal mean value of 0-77 +/- 0-07 (s.d.) g/cm. This 29% decrease is statistically significant (P...... less than 0-001). The transcapillary escape rate of albumin (TER alb) was significantly elevated, mean 8-6 +/- 1-1 (s.d.) % X h-1, as compared to normal subjects, mean 5-6 +/- 1-1 (s.d.) % X h-1, (+54%, P less than 0-001). The same patients were studied again after a 1-week treatment with prednisone...

  8. Focus on the research utility of intravascular ultrasound - comparison with other invasive modalities

    Directory of Open Access Journals (Sweden)

    Hoye Angela

    2011-01-01

    Full Text Available Abstract Intravascular ultrasound (IVUS is an invasive modality which provides cross-sectional images of a coronary artery. In these images both the lumen and outer vessel wall can be identified and accurate estimations of their dimensions and of the plaque burden can be obtained. In addition, further processing of the IVUS backscatter signal helps in the characterization of the type of the plaque and thus it has been used to study the natural history of the atherosclerotic evolution. On the other hand its indigenous limitations do not allow IVUS to assess accurately stent struts coverage, existence of thrombus or exact site of plaque rupture and to identify some of the features associated with increased plaque vulnerability. In order this information to be obtained, other modalities such as optical coherence tomography, angioscopy, near infrared spectroscopy and intravascular magnetic resonance imaging have either been utilized or are under evaluation. The aim of this review article is to present the current utilities of IVUS in research and to discuss its advantages and disadvantages over the other imaging techniques.

  9. Cardiac variation of inferior vena cava: new concept in the evaluation of intravascular blood volume.

    Science.gov (United States)

    Nakamura, Kensuke; Tomida, Makoto; Ando, Takehiro; Sen, Kon; Inokuchi, Ryota; Kobayashi, Etsuko; Nakajima, Susumu; Sakuma, Ichiro; Yahagi, Naoki

    2013-07-01

    Evaluation of the intravascular blood volume is an important assessment in emergency and critical care medicine. Measurement of the inferior vena cava (IVC) respiratory variation by ultrasound echography is useful, but it entails subjective problems. We have hypothesized that IVC cardiac variation is also correlated with intravascular blood volume and analyzed it automatically using computer software of two kinds, later comparing the results. Snakes, software to track boundaries by curve line continuity, and template matching software were incorporated into a computer with an ultrasound machine to track the short-axis view of IVC automatically and analyze it with approximation by ellipse. Eight healthy volunteers with temporary mild hypovolemia underwent echography before and after passive leg raising and while wearing medical anti-shock trousers. IVC cardiac variation was visually decreased by both leg raising and medical anti-shock trousers. The collapse index (maximum - minimum/maximum) of area during three cardiac beats was decreased showing a good relationship to fluid load simulations; 0.24 ± 0.03 at baseline versus 0.11 ± 0.01 with leg raising and 0.12 ± 0.01 with medical anti-shock trousers. In conclusion, IVC cardiac variation has the potential to provide an evaluation of water volume. It presents some advantages in mechanical analysis over respiratory variation. At the very least, we need to exercise some caution with cardiac variation when evaluating respiratory variation.

  10. One-stage surgery for removal of intravascular leiomyomatosis extending to right ventricle.

    Science.gov (United States)

    Chiang, Ching-Shu; Chen, Po-Lin; Kuo, Tzu-Ting; Chen, I-Ming; Wu, Nai-Yuan; Chang, Hsiao-Huang

    2018-03-01

    Intravascular leiomyomatosis (IVL) is a rare nonmalignant tumor that can be fatal if untreated. A 49-year-old nulliparous Asian woman who underwent hysterectomy and left salpingo-oophorectomy for multiple uterine leiomyomas 18 months prior presented complaining of intermittent palpitation and chest tightness for approximately 1 month. Echocardiography revealed a large mobile tumor mass extending from the inferior vena cava (IVC) to the right atrium that partially obstructed IVC flow and tricuspid inflow. Thoracicabdominopelvic computed tomography revealed a left adnexal tumor (4.8 × 2.5 cm) causing intravascular obstruction extending from the left internal iliac vein to the IVC, right atrium, and right ventricle. IVL with right heart involvement INTERVENTIONS:: Under cardiopulmonary bypass, a one-stage surgery combining sternotomy and laparotomy was performed. The tumor was approached and extracted via sternotomy, and tumor detachment and removal of residual tumors was accomplished via laparotomy. A firm, smooth, and regularly shape tumor 15.5 × 5.5 × 2.5 in size was completely removed and histopathologically confirmed as IVL. The patient tolerated the surgical procedure well and no postoperative complication was noted. We describe a one-stage surgical approach to completely remove an IVL extending to the right ventricle.

  11. Radiographic contrast media

    International Nuclear Information System (INIS)

    Golman, K.; Holtz, E.; Almen, T.

    1987-01-01

    Contrast media are used in diagnostic radiology to enhance the X-ray attenuation between a body structure of interest and the surrounding tissue. A detail becomes perceptible on a roentgenogram only when its contrast exceeds a minimum value in relation to the background. Small areas of interest must have higher contrast than the background. The contrast effect depends on concentration of the contrast media with the body. A high contrast media concentration difference thus gives rise to more morphological details in the radiographs. Contrast media can be divided into negative contrast media such as air and gas which attenuate X-rays less than the body tissues, and positive contrast materials which attenuate X-rays more than the body tissues. The positive contrast media all contain either iodine (atomic number 53) or barium (atomic number 56) and can be divided into water-insoluble and water-soluble contrast media

  12. Intravascular ultrasound assessment of minimumlumen area and intimal hyperplasia in in-stent restenosis after drug-eluting or bare-metal stent implantation. The Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Vikman, Saila; Antonsen, Lisbeth

    2017-01-01

    presenting with a DES or bare-metal stent (BMS) in-stent restenosis. Methods: The ``Nordic Intravascular Ultrasound Study (NIVUS)'' study was conducted in Nordic and Baltic countries as a prospective multicenter registry. Two hundred nine patients (DES n = 121 and BMS n = 88) with instent restenosis were...

  13. Intravascular Ultrasound

    Science.gov (United States)

    ... Rounds Seminar Series & Daily Conferences Fellowships and Residencies School of Perfusion Technology Education Resources Library & Learning Resource Center CME Resources THI Journal THI Cardiac Society Register for the Cardiac Society ...

  14. Interactions of ionic and nonionic contrast agents with thrombolytic agents

    International Nuclear Information System (INIS)

    Fareed, J.; Moncada, R.; Scanlon, P.; Hoppensteadt, D.; Huan, X.; Walenga, J.M.

    1987-01-01

    Both the ionic and nonionic intravascular contrast media have been used before and after the administration of thrombolytic agents to evaluate clot lysis during angioplasty and the treatment of myocardial infarction. In experimental animal models, the authors found that the clot lytic efficacy of streptokinase, streptokinase-plasminogen complex, and tissue plasminogen activator (t-PA) is markedly augmented if these agents are administered within 1 hour after the angiographic producers. Furthermore, contrast agents injected after the administration of t-Pa exhibit a synergistic action. In stimulated models administration of one ionic contrast medium (Angiovist, Berlex, Wayne, NJ) and two nonionic contrast agents (Isovue-370, Squibb Diagnostics, New Brunswick, NJ; Omnipaque-350, Winthrop, NY) 15 minutes before the administration of t-PA resulted in marked enhancement of the lytic activity. Although the mechanism of this interaction is unknown at this time, it should be taken into consideration in the treatment of patients with myocardial infarction, in whom contrast agents are continually used to evaluate the therapeutic lysis. Furthermore, this interaction may be partly related to the therapeutic efficacy and/or hemorrhagic actions observed

  15. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    NARCIS (Netherlands)

    Huisman, Jeroen; Egede, R.; Rdzanek, A.; Böse, D.; Erbel, R.; van der Palen, Jacobus Adrianus Maria; von Birgelen, Clemens

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility

  16. Direct sGC activation bypasses no scavenging reactions of intravascular free oxy-hemoglobin and limits vasoconstriction

    NARCIS (Netherlands)

    N.J.H. Raat (Nicolaas); D.M. Tabima (D. Marcela); P. Specht (Patricia); J. Tejero (Jesús); M.P. Champion (Michael); D.B. Kim-Shapiro (Daniel); J.G. Baust (John ); E.G. Mik (Egbert); M. Hildesheim (Mariana); J.-P. Stasch (Johannes-Peter); E.-M. Becker (Eva-Maria); H. Truebel (Hubert); M.T. Gladwin (Mark)

    2013-01-01

    textabstractAims: Hemoglobin-based oxygen carriers (HBOC) provide a potential alternative to red blood cell (RBC) transfusion. Their clinical application has been limited by adverse effects, in large part thought to be mediated by the intravascular scavenging of the vasodilator nitric oxide (NO) by

  17. Macromolecular contrast agents for MR mammography: current status

    International Nuclear Information System (INIS)

    Daldrup-Link, Heike E.; Brasch, Robert C.

    2003-01-01

    Macromolecular contrast media (MMCM) encompass a new class of diagnostic drugs that can be applied with dynamic MRI to extract both physiologic and morphologic information in breast lesions. Kinetic analysis of dynamic MMCM-enhanced MR data in breast tumor patients provides useful estimates of tumor blood volume and microvascular permeability, typically increased in cancer. These tumor characteristics can be applied to differentiate benign from malignant lesions, to define the angiogenesis status of cancers, and to monitor tumor response to therapy. The most immediate challenge to the development of MMCM-enhanced mammography is the identification of those candidate compounds that demonstrate the requisite long intravascular distribution and have the high tolerance necessary for clinical use. Potential mammographic applications and limitations of various MMCM, defined by either experimental animal testing or clinical testing in patients, are reviewed in this article. (orig.)

  18. Contrast-enhanced magnetic resonance imaging of tumours of the central nervous systems: a clinical review

    International Nuclear Information System (INIS)

    Graif, M.; Steiner, R.E.

    1986-01-01

    The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain, stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed. (author)

  19. Intravascular Large B-Cell Lymphoma Presenting as Interstitial Lung Disease

    Directory of Open Access Journals (Sweden)

    Elham Vali Khojeini

    2014-01-01

    Full Text Available Intravascular large B-cell lymphoma (IVLBL is a rare subtype of diffuse large B-cell lymphoma that resides in the lumen of blood vessels. Patients typically present with nonspecific findings, particularly bizarre neurologic symptoms, fever, and skin lesions. A woman presented with shortness of breath and a chest CT scan showed diffuse interstitial thickening and ground glass opacities suggestive of an interstitial lung disease. On physical exam she was noted to have splenomegaly. The patient died and at autopsy was found to have an IVLBL in her lungs as well as nearly all her organs that were sampled. Although rare, IVLBL should be included in the differential diagnosis of interstitial lung disease and this case underscores the importance of the continuation of autopsies.

  20. Application of Gafchromic registered film in the dosimetry of an intravascular brachytherapy source

    International Nuclear Information System (INIS)

    Song Haijun; Roa, D. Eduardo; Yue Ning; D'Errico, Francesco; Chen Zhe; Nath, Ravinder

    2006-01-01

    The methodology of brachytherapy source dosimetry with Gafchromic registered MD 55-2 film (ISP Technologies, Inc.) is examined with an emphasis on the nonlinearity of the optical density-dose relation within the dynamic dose range, the radial distance-dependent measurement uncertainty, and the format of data presentation. The specific source chosen for this study was a Checkmate trade mark sign (Cordis Corporation) intravascular brachytherapy system. The two-dimensional dose distribution around the source was characterized by a comprehensive analysis of measurement uncertainties. A comparative analysis of the dosimetric data from the vendor and from the scientific literature showed a substantial consistency of the information available for the Checkmate trade mark sign source. Our two-dimensional dosimetric data for the Checkmate trade mark sign source trains is presented in the form of measured along and away dose tables

  1. Intravascular Papillary Endothelial Hyperplasia (Masson’s Tumor) of the Radial Artery: A Case Report

    International Nuclear Information System (INIS)

    Stark, Christopher; Olsen, Daniel; Morris, Christopher; Bertges, Daniel; Najarian, Kenneth

    2016-01-01

    Intravascular papillary endothelial hyperplasia (IPEH), often referred to as Masson’s tumor, is a benign non-neoplastic vascular lesion of the skin and subcutaneous tissues. Although it is rare, knowledge of the existence of IPEH is important as it can mimic other benign and malignant tumors, most notably angiosarcoma. IPEH remains an incompletely understood entity; however, most consider it to be the result of reactive endothelial proliferation following thrombus formation within a vessel, vascular malformation, or adjacent to a vessel. In this article, we report a case of IPEH arising within an arteriovenous malformation of the radial artery and present accompanying multimodality imaging and pathology figures. We will also describe the clinical presentation, pathophysiology, histology, imaging features, and management of IPEH.

  2. Intravascular large B-cell lymphoma presenting with anasarca-type edema and acute renal failure.

    Science.gov (United States)

    Bilgili, Serap Gunes; Yılmaz, Deniz; Soyoral, Yasemin Usul; Karadag, Ayse Serap; Bayram, Irfan

    2013-09-01

    Intravascular lymphoma (IVL) is a rare extra nodal subtype (usually of B-cell origin) presenting with infiltration of large neoplastic lymphocytes into lumina of blood vessels, leading to vascular occlusion. The early diagnosis is very crucial, however it is usually diagnosed postmortem investigation in most of the cases. A 56-year-old female presented with elevated creatinine level, and anasarca-type edema that superimposed with hard, indurated, erythematous plaques extending to inguinal region, abdomen, anterior aspect of chest, and face. B-cell IVL was confirmed with skin biopsy. The patient had some degree of clinical improvement following chemotherapy. B-cell IVL presenting with anasarca edema was not previously reported in the literature. Even if its rarity, IVL should be considered in the differential diagnosis of renal failure with anasarca edema.

  3. A state-of-the-art review on segmentation algorithms in intravascular ultrasound (IVUS) images.

    Science.gov (United States)

    Katouzian, Amin; Angelini, Elsa D; Carlier, Stéphane G; Suri, Jasjit S; Navab, Nassir; Laine, Andrew F

    2012-09-01

    Over the past two decades, intravascular ultrasound (IVUS) image segmentation has remained a challenge for researchers while the use of this imaging modality is rapidly growing in catheterization procedures and in research studies. IVUS provides cross-sectional grayscale images of the arterial wall and the extent of atherosclerotic plaques with high spatial resolution in real time. In this paper, we review recently developed image processing methods for the detection of media-adventitia and luminal borders in IVUS images acquired with different transducers operating at frequencies ranging from 20 to 45 MHz. We discuss methodological challenges, lack of diversity in reported datasets, and weaknesses of quantification metrics that make IVUS segmentation still an open problem despite all efforts. In conclusion, we call for a common reference database, validation metrics, and ground-truth definition with which new and existing algorithms could be benchmarked.

  4. Intravascular Papillary Endothelial Hyperplasia (Masson’s Tumor) of the Radial Artery: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Stark, Christopher, E-mail: Christopher.stark@uvmhealth.org [University of Vermont Medical Center, Department of Radiology (United States); Olsen, Daniel [Mayo Clinic, Department of Pathology (United States); Morris, Christopher [University of Vermont Medical Center, Department of Radiology (United States); Bertges, Daniel [University of Vermont Medical Center, Department of Surgery (United States); Najarian, Kenneth [University of Vermont Medical Center, Department of Radiology (United States)

    2016-11-15

    Intravascular papillary endothelial hyperplasia (IPEH), often referred to as Masson’s tumor, is a benign non-neoplastic vascular lesion of the skin and subcutaneous tissues. Although it is rare, knowledge of the existence of IPEH is important as it can mimic other benign and malignant tumors, most notably angiosarcoma. IPEH remains an incompletely understood entity; however, most consider it to be the result of reactive endothelial proliferation following thrombus formation within a vessel, vascular malformation, or adjacent to a vessel. In this article, we report a case of IPEH arising within an arteriovenous malformation of the radial artery and present accompanying multimodality imaging and pathology figures. We will also describe the clinical presentation, pathophysiology, histology, imaging features, and management of IPEH.

  5. The role of the adventitia in the arterial response to angioplasty: the effect of intravascular radiation

    International Nuclear Information System (INIS)

    Wilcox, Josiah N.; Waksman, Ron; King, Spencer B.; Scott, Neal A.

    1996-01-01

    Purpose: In the current series of experiments we have characterized cell proliferation leading to vascular lesion formation in a porcine model for post-angioplasty restenosis and examined the mechanism of action of intravascular beta irradiation in the prevention of lesion formation in this model. Methods and Materials: Juvenile male pigs were subjected to balloon overstretch injury of the left anterior descending and circumflex coronary arteries using clinical angioplasty catheters. Proliferating cells were labelled by injections of 50 mg/kg of bromo-deoxyuridine (BrDU) 24, 16 and 8 hrs prior to sacrifice and were detected by immunohistochemistry using a specific antibody to BrDU. In some cases, BrDU was given as a pulse 3 days after angioplasty and the animals sacrificed on day 14 to follow the migration of the cells which had proliferated earlier. Characterization of the proliferating cells was performed by immunohistochemistry using antibodies to specific cytoskeletal proteins specific for smooth muscle cells and myofibroblasts. Some vessels were treated at the time of angioplasty with 14 or 28 Gy (to a depth of 2 mm) intravascular irradiation using a flexible catheter with a pure beta emitter 90 SR/Y and the effect on cell proliferation and terminal transferase-mediated UTP nick-end labelling (TUNEL) examined 3 or 7 days later. Results: The first major site of cell proliferation between 2-3 days after angioplasty is the adventitia and not the medial wall. Seven days after angioplasty cell proliferation is predominant in the neointima and is reduced in the media and adventitia. Differential staining with antibodies directed against smooth muscle alpha actin and other cytoskeletal proteins indicates that the proliferating adventitial cells are myofibroblasts. Pulse label studies with BrDU indicates that the proliferating adventitial myofibroblasts migrate into the neointima and contribute to the mass of the restenosis lesion. Fourteen days after angioplasty the

  6. Specific features of red blood cell morphology in hemolytic disease neonates undergoing intrauterine intravascular blood transfusion

    Directory of Open Access Journals (Sweden)

    A. V. Ivanova

    2016-01-01

    Full Text Available The paper presents data on the characteristics of red blood cell morphology in infants who have undergone intrauterine intravascular blood transfusion for hemolytic disease of the fetus. The infants are shown to have a reduction in the mean volume of red blood cells and in their mean level of hemoglobin, a decrease in the fraction of fetal hemoglobin and an increase in oxygen tension at half saturation. The above morphological characteristics of red blood cells remain decreased during the neonatal period after exchange transfusion or others, as clinically indicated, which seems to suggest that the compensatory-adaptive mechanisms to regulate hematopoiesis are exhausted and a donor’s red blood cells continue to be predominant.

  7. Histopathological approach for diagnosis of intravascular leiomyosarcoma of the femoral vein

    Directory of Open Access Journals (Sweden)

    Gaurav Singal

    2016-04-01

    Full Text Available Malignant tumors arising from venous walls in the lower extremities are uncommon and intravascular leiomyosarcoma represents only a small proportion and rare of soft tissue leiomyosarcoma. All publications in the literature are of small clinical series or case reports. We present a case of primary leiomyosarcoma of the femoral vein in a 40 year old man; which is a rare lesion with less than 40 cases reported. The patient presented with swelling and localized leg pain. The diagnosis was made histopathologically, the tumor was resected, vascular reconstruction was performed, and for postoperative radiation therapy and chemotherapy patient was referred to the oncologist. Primary leiomyosarcoma of a major peripheral artery is extremely rare, and this report share the clinical presentation, histopathological findings, treatment, and prognosis in these patients

  8. Splenic angiomyxoma with intravascular tumor embolus in a dog: a case report.

    Science.gov (United States)

    Lee, Eun-Mi; Kim, Ah-Young; Lee, Eun-Joo; Park, Jin-Kyu; Kim, Tae-Hwan; Park, Se-Il; Jeong, Kyu-Shik

    2016-07-01

    A 13-year-old castrated male Yorkshire terrier dog had a soft splenic mass, which measured 11 cm in the greatest diameter. Microscopically, the parenchyma of the spleen was completely replaced by myxoid substances. Numerous spindle and stellate cells were loosely arranged in the myxoid stroma, and variable vessels of variable sizes were observed in a loose matrix with poorly defined margins. Immunohistochemical analysis showed that tumor cells were positive for desmin and alpha-SMA, but negative for S-100. Interestingly, intravascular tumor embolus with positive α-SMA expression was observed. This case is meaningful, because angiomyxoma, a rare tumor of dogs, occurs in the spleen. Even in human cases, splenic angiomyxoma was not reported.

  9. Intravascular ultrasound assessment of remodelling and reference segment plaque burden in type-2 diabetic patients

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Mintz, Gary S

    2007-01-01

    AIMS: Intravascular ultrasound (IVUS) assesses arterial remodelling by comparing the lesion external elastic membrane (EEM) with the reference segments; however, reference segments are rarely disease-free. The aim was to assess lesion and reference segment remodelling and plaque burden in patients...... with type-2 diabetes mellitus. METHODS AND RESULTS: We used pre-intervention IVUS to study 62 de novo lesions in 43 patients with type-2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal...... size [slope = -0.12 (95% CI -0.17 to -0.07); P type-2 diabetes mellitus. CONCLUSION: Lesions in type-2 diabetic patients are different from previous reports in non-diabetics. Lesions in type-2 diabetics are characterized by a large reference segment plaque burden...

  10. Early Blood Transfusion and Resolution of Disseminated Intravascular Coagulation Associated with Massive Subgaleal Hemorrhage.

    Science.gov (United States)

    Modanlou, Houchang; Hutson, Shandee; Merritt, Allan Thurman

    2016-01-01

    A male infant delivered to a primipara woman following vacuum applications. He was vigorous at birth, with small caput and scalp bruising. His head was enlarging; he became pale with respiratory distress. Subgaleal hemorrhage (SGH) was suspected. His hematocrit was noted to be 26.2 percent prior to transfusion of O, Rh-negative blood (40 mL/kg). Moderate disseminated intravascular coagulation (DIC) was noted at 12 hours of age. Posttransfusion of fresh frozen plasma (FFP), his condition became stable, and DIC gradually resolved. Head magnetic resonance imaging did not show intracranial hemorrhage. Although one episode of seizures was noted, electroencephalogram was normal. With the application of obstetric vacuum, we recommend that the neonatal health care professionals frequently evaluate the infant's condition. In light of developing fluctuant subgaleal fluid associated with pallor, anemia, metabolic acidosis, and respiratory distress, immediate blood transfusion is warranted. In the presence of DIC, transfusion of FFP is beneficial.

  11. Catheter design optimization for practical intravascular photoacoustic imaging (IVPA) of vulnerable plaques

    Science.gov (United States)

    Iskander-Rizk, Sophinese; Wu, Min; Springeling, Geert; Mastik, Frits; Beurskens, Robert H. S. H.; van der Steen, Antonius F. W.; van Soest, Gijs

    2018-02-01

    Intravascular photoacoustic/ultrasound imaging (IVPA/US) can image the structure and composition of atherosclerotic lesions identifying lipid-rich plaques ex vivo and in vivo. In the literature, multiple IVPA/US catheter designs were presented and validated both in ex-vivo models and preclinical in-vivo situations. Since the catheter is a critical component of the imaging system, we discuss here a catheter design oriented to imaging plaque in a realistic and translatable setting. We present a catheter optimized for light delivery, manageable flush parameters and robustness with reduced mechanical damage risks at the laser/catheter joint interface. We also show capability of imaging within sheath and in water medium.

  12. An automated approach for segmentation of intravascular ultrasound images based on parametric active contour models

    International Nuclear Information System (INIS)

    Vard, Alireza; Jamshidi, Kamal; Movahhedinia, Naser

    2012-01-01

    This paper presents a fully automated approach to detect the intima and media-adventitia borders in intravascular ultrasound images based on parametric active contour models. To detect the intima border, we compute a new image feature applying a combination of short-term autocorrelations calculated for the contour pixels. These feature values are employed to define an energy function of the active contour called normalized cumulative short-term autocorrelation. Exploiting this energy function, the intima border is separated accurately from the blood region contaminated by high speckle noise. To extract media-adventitia boundary, we define a new form of energy function based on edge, texture and spring forces for the active contour. Utilizing this active contour, the media-adventitia border is identified correctly even in presence of branch openings and calcifications. Experimental results indicate accuracy of the proposed methods. In addition, statistical analysis demonstrates high conformity between manual tracing and the results obtained by the proposed approaches.

  13. Comparison of angiography and intravascular ultrasound before and after balloon angioplasty of the femoropopliteal artery

    International Nuclear Information System (INIS)

    Lankeren, Winnifred van; Gussenhoven, Elma J.; Pieterman, Herman; Sambeek, Marc R. H. M. van; Lugt, Aad van der

    1998-01-01

    Purpose: To compare angiographic and intravascular ultrasound (IVUS) data before and after balloon angioplasty (PTA) of the femoropopliteal artery.Methods: Qualitative and quantitative analyses were performed on corresponding angiographic and IVUS levels obtained from 135 patients.Results: IVUS detected more lesions, calcified lesions, and vascular damage than angiography. Sensitivity of angiography was good for the presence of a lesion (84%), moderate for eccentric lesions (53%) and for vascular damage (52%), and poor for calcified lesions (30%). The increase in angiographic diameter stenosis was associated with a decrease in lumen area and increase in percentage area stenosis on IVUS.Conclusions: Angiography is less sensitive than IVUS for detecting lesion eccentricity, calcified lesions, and vascular damage. Presence of a lesion and amount of plaque were underestimated angiographically. Only before PTA was good agreement found between angiographic diameter stenosis and lumen size on IVUS.

  14. Perspectives on Imaging the Left Main Coronary Artery Using Intravascular Ultrasound and Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Harry C Lowe

    2015-01-01

    Full Text Available Percutaneous Coronary Intervention (PCI for significant left main coronary artery (LMCA stenosis is increasingly being viewed as a viable alternative to Coronary Artery Bypass Grafting (CABG (1. This is leading to an expectation of increasing numbers of such procedures, with a consequent focus on both the ability to image both lesion severity, and assess more accurately the results of PCI. While there have been advances in physiologic assessment of left main severity using fractional flow reserve (FFR, imaging of the LMCA using Intravascular Ultrasound (IVUS and more recently Optical Coherence Tomography (OCT has the specific advantage of being able to provide detailed anatomical information both pre and post PCI, such that it is timely to review briefly the current status of these two imaging technologies in the context of LMCA intervention.

  15. Intravascular papillary endothelial hyperplasia of the extremities: MR imaging findings with pathologic correlation

    International Nuclear Information System (INIS)

    Lee, Sang Hoon; Suh, Jin-Suck; Lim, Byung Il; Yang, Woo Ick; Shin, Kyoo-Ho

    2004-01-01

    We report the MRI findings of three cases of intravascular papillary endothelial hyperplasia (IPEH) of the extremities with correlation of the pathologic findings. The IPEH is a non-neoplastic reactive lesion within the vessels and is commonly associated with thrombi. Signal intensity of the IPEH is complex due to the thrombi and the PEH itself. The thrombi are characterized by a slightly hyperintense signal on T1- and T2-weighted images compared with that of muscle when it comes at the medium stage of hemorrhage. Papillary endothelial hyperplastic tissue appears either as iso- or hyperintense to the muscle on T2- and T1-weighted images and shows variable enhancement on Gd-DTPA-enhanced images. (orig.)

  16. Tracer kinetic model selection for dynamic contrast-enhanced magnetic resonance imaging of locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Kallehauge, Jesper Folsted; Tanderup, Kari; Duan, Chong

    2014-01-01

    , the TM was optimal in 17.0%, the ETM was optimal in 2.2%, the C-TU in 23.4% and the 2CXM was optimal in 57.3%. Throughout the tumour, a high correlation was found between Ktrans(TM) and Fp(2CXM), ρ = 0.91. Conclusion. The 2CXM was most often optimal in describing the contrast agent enhancement of pre......Background. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) offers a unique capability to probe tumour microvasculature. Different analysis of the acquired data will possibly lead to different conclusions. Therefore, the objective of this study was to investigate under which...

  17. Establishment of virtual three-dimensional model for intravascular interventional devices and its clinical value

    International Nuclear Information System (INIS)

    Wei Xin; Zhong Liming; Xie Xiaodong; Wang Chaohua; You Jian; Hu Hong; Hu Kongqiong; Zhao Xiaowei

    2012-01-01

    Objective: To explore virtual three-dimensional (3D) model for intravascular interventional devices,the method of preoperative simulation and its value in clinical work. Methods: The virtual models including catheter, guide wire, stent and coil were established by using the 3D moulding software of 3D Studio MAX R3. The interventional preoperative simulation was performed on personal computer including 21 patients of cerebral aneurysm embolization (anterior communicating artery 5, posterior communicating artery 10,middle cerebral artery 3, internal carotid artery 2, and vertebral artery 1), during interventional procedures, the surgeon relied on the simulation results for plastic micro-guide wire, catheter and the release of micro-coils and stents. Results: (1) All the virtual instruments and real instruments had similar shape,the overall tine for constructing virtual model was about 20 hours. The preoperative simulation took 50 to 80 minutes. (2) The simulation result of catheter insertion in the 18 cases had relevant value to guide micro-catheter, molding micro-guide wire tip, and shortened the operating time. For embolization, the simulation results of filling coil and releasing stent were similar to surgical results in 76% of the patients (16/21). (3)For teaching and training, 93% (38/41) of doctors in training believed that preoperative simulation facilitated the understanding of surgery. Conclusions: The method of virtual model of intravascular interventional devices was reliable. The preoperative simulation results could be used to guide practical clinical operation with relatively high degree of similarity, and could play a role in promoting researches on interventional virtual operations. (authors)

  18. Intravascular large B-cell lymphoma of the kidney: A case report

    Directory of Open Access Journals (Sweden)

    Jia Nan

    2011-09-01

    Full Text Available Abstract We report a 41-year-old Chinese woman with intravascular large B-cell lymphoma diagnosed by percutaneous renal biopsy. The patient was admitted to Nanfang Hospital of Southern Medical University, Guangzhou, China with complaints of high spiking fever for a month and bilateral lower limb fatigue with difficulty ambulating for the past 5 months. She had renal dysfunction with a total urinary protein of 5.61 g/dL (56.1 g/L, serum albumin of 2.89 g/dL (28.9 g/L, urea nitrogen of 2.24 mg/dL (1.6 mmol/L, and serum creatinine of 0.54 mg/dL (48 μmol/L. Bone marrow biopsy revealed myeloproliferative disorder without abnormal myeloid or lymphocytic proliferation. Positron Emission Tomography-Computed Tomography (PET-CT showed marked bilateral swelling and enlargement of the renal parenchyma with splenic enlargement and involvement of multiple vertebrae. Percutaneous renal biopsy showed island-like accumulations of medium to large lymphoid cells in many areas of the interstitium, with round vesicular nuclei containing distinct basophilic nucleoli. Immunohistochemical analysis together with other supportive investigation confirmed the diagnosis of intravascular large B-cell lymphoma. Ten days later, she was started on chemotherapy with CHOP (cyclophosphamide, doxorubicin, leurocristime and prednisone for a week. Palliative radiotherapy DT 40Gy/20F with other supportive treatment was provided for metastatic foci in the medullary cavity of the sternum, T1-T7. The patient regained muscle strength in both lower limbs and was able to walk again after three weeks. The patient was discharged after hepatic and renal function and proteinuria values had returned to normal. Follow-up data shows the patient to be alive nine months after discharge.

  19. Prediction of postpercutaneous coronary intervention myocardial infarction: insights from intravascular imaging, coronary flow, and biomarker evaluation.

    Science.gov (United States)

    Hoole, Stephen P; Hernández-Sánchez, Jules; Brown, Adam J; Giblett, Joel P; Bennett, Martin R; West, Nick E J

    2018-05-01

    Percutaneous coronary intervention-induced myocardial infarction (PMI) has prognostic significance. Identifying patients at high risk for PMI is desirable as it may alter strategy and facilitate early preventative therapy. We therefore sought to establish whether preprocedural demographic, interventional (plaque characteristics and coronary microcirculatory function), and inflammatory, endothelial damage, and platelet-derived biomarker data could predict the risk of PMI. We performed target vessel pressure wire to assess fractional flow reserve, index of microcirculatory resistance (IMR) and coronary flow reserve, plaque characterization by virtual histology intravascular ultrasound, and assayed peripheral biomarkers before uncomplicated PCI in 88 patients. We then analyzed post-PCI cardiac troponin level to adjudicate PMI based on the third universal definition of myocardial infarction. Overall incidence of PMI was 27%. Women [10/15 (66%) vs. 14/73 (19%), PPMI. Preprocedural coronary flow reserve was lower in individuals with a subsequent PMI (1.8±1.2 vs. 2.1±1.3. P=0.03), and patients with higher pre-PCI IMR were more likely to sustain PMI [IMR>22: 10/23 (44%) vs. ≤22: 14/65 (22%), P=0.04], although neither was predictive after multivariate analysis. Plaque characterization by virtual histology intravascular ultrasound did not discriminate those at risk of PMI. However, peripheral venous interleukin (IL)-18 and IL-8 levels were independently negatively and positively associated with PMI, respectively. Women and those with low BMI, particularly when associated with high IL-8 and low IL-18 levels, appear to be at increased risk of PMI.

  20. The effects of serial intravascular transfusions in ascitic/hydropic RhD-alloimmunized fetuses.

    Science.gov (United States)

    Craparo, F J; Bonati, F; Gementi, P; Nicolini, U

    2005-02-01

    To evaluate the effects of serial intravascular transfusions on RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion by measuring multiple hematological/biochemical blood variables. Thirty-one singleton pregnancies were referred for management of RhD alloimmunization. Seven fetuses had hydrops on presentation and were transfused immediately. The remainder underwent weekly ultrasound examinations, and fetal blood sampling and transfusion were performed on development of ascites. In the 104 samples collected overall from the 31 fetuses, glucose, uric acid, urea, creatinine, total protein, total and direct bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase, alkaline phosphatase, lactic dehydrogenase, amylase, pseudocholinesterase (PCHE), creatine kinase, triglycerides and cholesterol were measured and compared with a reference range for non-anemic fetuses. The median gestational age at first transfusion was 26 (range, 18-34) weeks. There were three fetal losses after the first transfusion, two of which were due to procedure-related complications; one further loss occurred. At the first transfusion fetal hematocrit, pO2, total protein, PCHE, creatinine and urea concentrations were significantly decreased compared to reference data, while total and direct bilirubin, AST, ALT, amylase, triglyceride and uric acid concentrations were increased. In all surviving fetuses ascites/hydrops had disappeared by the second transfusion. Fetal pO2, total protein, AST, ALT and PCHE concentrations had normalized by the third transfusion. Correction of fetal anemia did not affect the other variables. RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion had a survival rate of 87%. Alterations of several biochemical fetal blood indices are present at the first sampling/transfusion, but most variables normalize with intravascular transfusions. Copyright 2005 ISUOG.

  1. Evaluation of cerebral intravascular blood flow by time density curve study of intravenous digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Imamura, Toru; Kogure, Kyuya (Tohoku Univ., Sendai (Japan). School of Medicine); Sekine, Teiko; Satoh, Kei; Endoh, Minoru; Tsuburaya, Kenji; Hoshi, Akihiko

    1992-01-01

    Time density curve (TDC) can be reconstructed from the data of intravenous digital subtraction angiography (IVDSA). We evaluated peak time (PT) and modal transit time (MOTT) of the TDC as the probable indicator of cerebral intravascular blood flow. Cerebral IVDSA and single photon emission CT (SPECT) were performed on 12 patients with ischemic cerebrovascular disease, which consisted of 3 internal carotid artery (ICA) occlusions, one middle cerebral artery (MCA) occlusion, one anterior cerebral artery (ACA) branch occlusion and 7 lacunar infarctions. We classified former 4 patients as occlusion group and latter 8 as reference group. In 3 patients (2 ICA and one MCA occlusions), SPECT study revealed definite hypoaccumulation in the MCA territory of occlusive side. Two regions of interest (ROI) were placed on the territories of right and left middle cerebral arteries in the frontal view of cerebral IVDSA. Digital data processor fitted {gamma} curve to the TDC of each ROI, and calculated PT and MOTT. The absolute lateralities of PT and MOTT of MCA territory was significantly (p<0.05) larger in occlusion group than reference group. Patients with hypoaccumulation in SPECT had significantly (p<0.02) larger laterality of MOTT than patients with isoaccumulation. One ICA occluded patient without hypoaccumulation in corresponding MCA territory had relatively small laterality of MOTT similar to the patients of ACA branch occlusion and lacunar infarction. These results suggest that PT and MOTT are possible to detect the laterality of the intravascular blood flow in MCA territories caused by major artery occlusion. Cerebral TDC study of IVDSA may be useful in some clinical therapeutic situations such as hemodilution or intra-arterial thrombolysis, and worth further clinical evaluation. (author).

  2. Prospective implementation of an algorithm for bedside intravascular ultrasound-guided filter placement in critically ill patients.

    Science.gov (United States)

    Killingsworth, Christopher D; Taylor, Steven M; Patterson, Mark A; Weinberg, Jordan A; McGwin, Gerald; Melton, Sherry M; Reiff, Donald A; Kerby, Jeffrey D; Rue, Loring W; Jordan, William D; Passman, Marc A

    2010-05-01

    Although contrast venography is the standard imaging method for inferior vena cava (IVC) filter insertion, intravascular ultrasound (IVUS) imaging is a safe and effective option that allows for bedside filter placement and is especially advantageous for immobilized critically ill patients by limiting resource use, risk of transportation, and cost. This study reviewed the effectiveness of a prospectively implemented algorithm for IVUS-guided IVC filter placement in this high-risk population. Current evidence-based guidelines were used to create a clinical decision algorithm for IVUS-guided IVC filter placement in critically ill patients. After a defined lead-in phase to allow dissemination of techniques, the algorithm was prospectively implemented on January 1, 2008. Data were collected for 1 year using accepted reporting standards and a quality assurance review performed based on intent-to-treat at 6, 12, and 18 months. As defined in the prospectively implemented algorithm, 109 patients met criteria for IVUS-directed bedside IVC filter placement. Technical feasibility was 98.1%. Only 2 patients had inadequate IVUS visualization for bedside filter placement and required subsequent placement in the endovascular suite. Technical success, defined as proper deployment in an infrarenal position, was achieved in 104 of the remaining 107 patients (97.2%). The filter was permanent in 21 (19.6%) and retrievable in 86 (80.3%). The single-puncture technique was used in 101 (94.4%), with additional dual access required in 6 (5.6%). Periprocedural complications were rare but included malpositioning requiring retrieval and repositioning in three patients, filter tilt >/=15 degrees in two, and arteriovenous fistula in one. The 30-day mortality rate for the bedside group was 5.5%, with no filter-related deaths. Successful placement of IVC filters using IVUS-guided imaging at the bedside in critically ill patients can be established through an evidence-based prospectively

  3. Contrast induced nephropathy

    DEFF Research Database (Denmark)

    Stacul, Fulvio; van der Molen, Aart J; Reimer, Peter

    2011-01-01

    PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic me...

  4. Generalized phase contrast:

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Palima, Darwin

    Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast...

  5. Sonographic evaluation of intravascular volume status: Can internal jugular or femoral vein collapsibility be used in the absence of IVC visualization?

    Directory of Open Access Journals (Sweden)

    Alistair Kent

    2015-01-01

    Full Text Available Introduction: Inferior vena cava collapsibility index (IVC-CI has been shown to correlate with both clinical and invasive assessment of intravascular volume status, but has important limitations such as the requirement for advanced sonographic skills, the degree of difficulty in obtaining those skills, and often challenging visualization of the IVC in the postoperative patient. The current study aims to explore the potential for using femoral (FV or internal jugular (IJV vein collapsibility as alternative sonographic options in the absence of adequate IVC visualization. Methods: A prospective, observational study comparing IVC-CI and Fem- and/or IJV-CI was performed in two intensive care units (ICU between January 2012 and April 2014. Concurrent M-mode measurements of IVC-CI and FV- and/or IJV-CI were collected during each sonographic session. Measurements of IVC were obtained using standard technique. IJV-CI and FV-CI were measured using high-frequency, linear array ultrasound probe placed in the corresponding anatomic areas. Paired data were analyzed using coefficient of correlation/determination and Bland-Altman determination of measurement bias. Results: We performed paired ultrasound examination of IVC-IJV (n = 39 and IVC-FV (n = 22, in 40 patients (mean age 54.1; 40% women. Both FV-CI and IJV-CI scans took less time to complete than IVC-CI scans (both, P < 0.02. Correlations between IVC-CI/FV-CI (R 2 = 0.41 and IVC-CI/IJV-CI (R 2 = 0.38 were weak. There was a mean -3.5% measurement bias between IVC-CI and IJV-CI, with trend toward overestimation for IJV-CI with increasing collapsibility. In contrast, FV-CI underestimated collapsibility by approximately 3.8% across the measured collapsibility range. Conclusion: Despite small measurement biases, correlations between IVC-CI and FV-/IJV-CI are weak. These results indicate that IJ-CI and FV-CI should not be used as a primary intravascular volume assessment tool for clinical decision support in

  6. [Optimal intravascular brachytherapy: safety and radiation protection, reliability and precision guaranteed by guidelines, recommendations and regulatory requirements].

    Science.gov (United States)

    Quast, Ulrich; Kaulich, Theodor W; Lorenz, Joachim

    2002-02-01

    The success of intravascular brachytherapy relies entirely on the interdisciplinary approach. Interventional cardiologists, radiation oncologists and medical physicists must form a team from day 1. All members of the team need special knowledge and regular training in the field of vascular radiation therapy. Optimization of intravascular brachytherapy requires the use of standardized methods of dose specification, recording and reporting. This also implies using standardized methods of source calibration in terms of absorbed dose to water and having methods for simple internal control of the dosimetric quantities of new or replaced sources. Guidance is offered by international recommendations (AAPM TG 60, DGMP Report 16, NCS and EVA GEC-ESTRO). LEGAL REQUIREMENTS FOR RADIATION PROTECTION--WHAT'S NEW?: In Europe, new legal requirements on radiation protection issues have to be fulfilled. For Germany, the revised "Strahlenschutzverordnung" has been released recently. Nearly all organizational and medical processes are affected. For intravascular brachytherapy, several changes of requirements have to be considered. However, to follow these requirements does not cause serious problems. DGMP REPORT 16: GUIDELINES FOR MEDICAL PHYSICAL ASPECTS OF INTRAVASCULAR BRACHYTHERAPY: Evaluation of clinical results by comparison of intravascular brachytherapy treatment parameters is possible only if the prescribed dose and the applied dose distribution are reported clearly, completely and uniformly. The DGMP guidelines thus recommend to prescribe the dose to water at the system related reference point PRef at 2 mm radial distance for intracoronary application (and at 5 mm for peripheral vessels). The mean dose at 1 mm tissue depth (respectively at 2 mm) should be reported in addition. To safely define the planning target volume from the injured length, safety margins of at least 5 mm (10 mm) have to be taken into account on both ends. Safety margins have also to be considered for

  7. Perforations during contrast enema

    International Nuclear Information System (INIS)

    Vogel, H.; Steinkamp, U.; Grabbe, E.; Allgemeines Krankenhaus Ochsenzoll, Hamburg

    1983-01-01

    During contrast enema, perforation into the retroperitoneal space can be differentiated from perforation into the peritoneum and perforation into the intestinal wall associated with formation of barium granulomas or submucosal spreading of the contrast medium. Other special forms are perforation with contrast medium embolism of diverticula; of the processus vermiformis; penetration of contrast medium into fistulous systems and from the operated areas. Risk factors are: balloon catheter, intestinal tubes with a hard tip, preternatural anus, excessive enema pressure, contrast medium additions, preceding manipulations, intestinal diseases, advanced age and delegation of manipulations to assistants and unskilled staff. Children are particularly at risk. (orig.) [de

  8. Contrast induced nephropathy

    DEFF Research Database (Denmark)

    Stacul, Fulvio; van der Molen, Aart J; Reimer, Peter

    2011-01-01

    PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic me....../min/1.73 m (2) is CIN risk threshold for intravenous contrast medium. • Hydration with either saline or sodium bicarbonate reduces CIN incidence. • Patients with eGFR = 60 ml/min/1.73 m (2) receiving contrast medium can continue metformin normally....

  9. Myocardial contrast defect associated with thrombotic coronary occlusion: Pre-autopsy diagnosis of a cardiac death with post-mortem CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Heon; Cha, Jang Gyu [Dept. of Radiology, Soonchunhyang University Hospital, Bucheon (Korea, Republic of); Park, Hye Jin; Lee, Soo Kyoung; Yang, Kyung Moo [Dept. of Forensic Medicine, National Forensic Service, Wonju (Korea, Republic of)

    2015-10-15

    We report the case of a female who died of suspected acute myocardial infarction. Post-mortem CT angiography (PMCTA) was performed with intravascular contrast infusion before the standard autopsy, and it successfully demonstrated the complete thrombotic occlusion of a coronary artery and also a corresponding perfusion defect on myocardium. We herein describe the PMCTA findings of a cardiac death with special emphasis on the potential benefits of this novel CT technique in forensic practice.

  10. Reduction of exit-site infections of tunnelled intravascular catheters among neutropenic patients by sustained-release chlorhexidine dressings: results from a prospective randomized controlled trial.

    Science.gov (United States)

    Chambers, S T; Sanders, J; Patton, W N; Ganly, P; Birch, M; Crump, J A; Spearing, R L

    2005-09-01

    Exit-site and tunnel infections of tunnelled central intravascular catheters are a frequent source of morbidity among neutropenic patients and may necessitate catheter removal. They require antimicrobial therapy that increases healthcare costs and is associated with adverse drug reactions. A prospective randomized clinical trial was conducted among adult patients undergoing chemotherapy in a haematology unit. Tunnelled intravascular catheters were randomized to receive the control of a standard dressing regimen as recommended by the British Committee for Standards in Haematology, or to receive the intervention of a sustained-release chlorhexidine dressing. Follow-up data were available in 112 of 114 tunnelled intravascular catheters which were randomized. Exit-site or combined exit-site/tunnel infections occurred in 23 (43%) of 54 catheters in the control group, and five (9%) of 58 catheters in the intervention group [odds ratio (OR) for intervention group compared with control group =0.13, 95% confidence intervals (CI) 0.04-0.37, P<0.001]. More tunnelled intravascular catheters were prematurely removed from the control group than the intervention group for documented infections [20/54 (37%) vs 6/58 (10%), OR=0.20, 95%CI 0.53-0.07]. However, there was no difference in the numbers of tunnelled intravascular catheters removed for all proven and suspected intravascular catheter-related infections [21/54 (39%) vs 19/58 (33%)], or in the time to removal of catheters for any reason other than death or end of treatment for underlying disease. Thus chlorhexidine dressings reduced the incidence of exit-site/tunnel infections of indwelling tunnelled intravascular catheters without prolonging catheter survival in neutropenic patients, and could be considered as part of the routine management of indwelling tunnelled intravascular catheters among neutropenic patients.

  11. Head to head comparison of optical coherence tomography, intravascular ultrasound echogenicity and virtual histology for the detection of changes in polymeric struts over time

    DEFF Research Database (Denmark)

    Brugaletta, Salvatore; Gomez-Lara, Josep; Bruining, Nico

    2012-01-01

    To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation. In the A......To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation...

  12. 3D dosimetry study of 188Re liquid balloon for intravascular brachytherapy using BANG polymer gel dosemeters

    International Nuclear Information System (INIS)

    Wuu, S.; Schiff, P.B.; Maryanski, M.; Liu, T.; Borzillary, S.; Weinberger, J.

    2002-01-01

    It has been suggested that the combination of intravascular brachytherapy and coronary stent implantation may result in further reduction of restenosis after percutaneous balloon angioplasty. The use of an angioplasty balloon filled with a P 188 Re liquid beta source for intravascular brachytherapy provides the advantage of accurate source positioning and uniform dose distribution to the coronary vessel wall. The effect of source edge and stent on the dose distribution of the target tissue may be clinically important. In BANG gels, the absorbed radiation produces free-radical chain polymerisation of acrylic monomers that are initially dissolved in the gel. The number of polymer particles is proportional to the absorbed dose. In this study, 3D dose distributions are presented for 188 Re balloons, with and without stents, using a prototype He-Ne laser CT scanner and the proprietary BANG polymer gel dosemeters. (author)

  13. Studies on polyaspartamide gadolinium complexes as potential magnetic resonance imaging contrast agents

    International Nuclear Information System (INIS)

    Yan Guoping; Liu Maili; Li Liyun

    2005-01-01

    Purpose: A series of polyaspartamide gadolinium complexes containing pyridoxamine groups were studied as the potential magnetic resonance imaging (MRI) contrast agents for liver enhancement. Methods: These polyaspartamide gadolinium complexes were prepared and evaluated by relaxivity, acute toxicity studies and magnetic resonance imaging of the liver in rats. Results: These polyaspartamide gadolinium complexes have higher relaxation effectiveness than that of the clinically used gadolinium diethylenetriaminepentaacetic acid and possess the low intravenous acute toxicities to Institute for Cancer Research (ICR) mice. Magnetic resonance imaging of the liver in rats indicated that they greatly enhance the contrast of magnetic resonance images and provide prolonged intravascular duration in the liver. Conclusion: These results indicated that the polyaspartamide gadolinium complexes containing pyridoxamine groups could be considered as the appropriate MRI contrast agents for liver enhancement

  14. Specific features of a neonatal period in infants following intrauterine intravascular blood transfusion for fetal hemolytic disease

    Directory of Open Access Journals (Sweden)

    A. V. Ivanova

    2015-01-01

    Full Text Available The paper gives data on the characteristics of a neonatal period in infants following intrauterine blood transfusion for Rh-induced fetal hemolytic disease. It is shown that the early diagnosis and detection of the signs of fetal hemolytic disease, and intrauterine intravascular blood transfusion may prolong pregnancy, ensure the birth of a baby with normal anthropometric indicators, optimize his/her neonatal period and prognosis of severe hemolytic disease in the fetus and newborn.

  15. Lumen and calcium characteristics within calcified coronary lesions. Comparison of computed tomography coronary angiography versus intravascular ultrasound

    OpenAIRE

    Noll, Dariusz; Kruk, Mariusz; Pręgowski, Jerzy; Kaczmarska, Edyta; Kryczka, Karolina; Pracoń, Radosław; Skwarek, Mirosław; Dzielińska, Zofia; Petryka, Joanna; Śpiewak, Mateusz; Lubiszewska, Barbara; Norwa-Otto, Bożena; Opolski, Maksymilian; Witkowski, Adam; Demkow, Marcin

    2013-01-01

    Introduction Computed tomography coronary angiography (CTCA) is a diagnostic method used for exclusion of coronary artery disease. However, lower accuracy of CTCA in assessment of calcified lesions is a significant factor impeding applicability of CTCA for assessment of coronary atherosclerosis. Aim To provide insight into lumen and calcium characteristics assessed with CTCA, we compared these parameters to the reference of intravascular ultrasound (IVUS). Material and methods Two hundred and...

  16. Phase contrast image synthesis

    DEFF Research Database (Denmark)

    Glückstad, J.

    1996-01-01

    A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase funct...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....

  17. Dose-volume histograms based on serial intravascular ultrasound: a calculation model for radioactive stents

    International Nuclear Information System (INIS)

    Kirisits, Christian; Wexberg, Paul; Gottsauner-Wolf, Michael; Pokrajac, Boris; Ortmann, Elisabeth; Aiginger, Hannes; Glogar, Dietmar; Poetter, Richard

    2001-01-01

    Background and purpose: Radioactive stents are under investigation for reduction of coronary restenosis. However, the actual dose delivered to specific parts of the coronary artery wall based on the individual vessel anatomy has not been determined so far. Dose-volume histograms (DVHs) permit an estimation of the actual dose absorbed by the target volume. We present a method to calculate DVHs based on intravascular ultrasound (IVUS) measurements to determine the dose distribution within the vessel wall. Materials and methods: Ten patients were studied by intravascular ultrasound after radioactive stenting (BX Stent, P-32, 15-mm length) to obtain tomographic cross-sections of the treated segments. We developed a computer algorithm using the actual dose distribution of the stent to calculate differential and cumulative DVHs. The minimal target dose, the mean target dose, the minimal doses delivered to 10 and 90% of the adventitia (DV10, DV90), and the percentage of volume receiving a reference dose at 0.5 mm from the stent surface cumulated over 28 days were derived from the DVH plots. Results were expressed as mean±SD. Results: The mean activity of the stents was 438±140 kBq at implantation. The mean reference dose was 111±35 Gy, whereas the calculated mean target dose within the adventitia along the stent was 68±20 Gy. On average, DV90 and DV10 were 33±9 Gy and 117±41 Gy, respectively. Expanding the target volume to include 2.5-mm-long segments at the proximal and distal ends of the stent, the calculated mean target dose decreased to 55±17 Gy, and DV 90 and DV 10 were 6.4±2.4 Gy and 107±36 Gy, respectively. Conclusions: The assessment of DVHs seems in principle to be a valuable tool for both prospective and retrospective analysis of dose-distribution of radioactive stents. It may provide the basis to adapt treatment planning in coronary brachytherapy to the common standards of radiotherapy

  18. Efficacy of alfaxalone for intravascular anesthesia and euthanasia in blue crabs (Callinectes sapidus).

    Science.gov (United States)

    Minter, Larry J; Harms, Craig A; Archibald, Kate E; Broadhurst, Heather; Bailey, Kate M; Christiansen, Emily F; Lewbart, Gregory A; Posner, Lysa P

    2013-09-01

    The objective of this study was to characterize the behavioral effects and changes in heart rate of four doses of alfaxalone delivered by intravascular injection to blue crabs (Callinectes sapidus). Thirty (male, n = 27; female, n = 3) blue crabs were randomly assigned to one of four treatment groups of alfaxalone: eight animals were assigned to each of the 5-, 10-, and 15-mg/kg treatment groups, and the remaining six animals were assigned to the 100-mg/kg group. Times for anesthetic induction and recovery periods were recorded. Righting reflex, defensive posturing, and heart rate were evaluated before, during, and after the anesthetic trial. Anesthesia was induced in all 14 animals consolidated into the high-dosage group (15 mg/kg [n = 8] and 100 mg/kg [n = 6]), which was significantly greater than 8 of 16 animals in the low-dosage group (5 mg/kg [n = 2] and 10 mg/kg [n = 6]). Median anesthesia induction time for all crabs was 0.4 min, with no significant difference in induction time between groups observed. Median recovery time was 9.4 min (n = 2), 6.1 min (n = 5), 11.3 min (n = 8), and 66.1 min (n = 5) for the 5-, 10-, 15-, and 100-mg/kg groups, respectively. Recovery times were significantly longer for crabs exposed to an induction dose of 100 mg/kg compared with the 10- and 15-mg/kg induction doses. A significant decrease in the median heart rate was observed between the baseline value and that observed at both induction and 5 min postinjection in the 100-mg/kg dose trial. Two mortalities were observed during the anesthesia trials (n = 1, 10 mg/kg; n = 1, 100 mg/kg), both associated with the autotomization of limbs. In summary, the intravascular administration of alfaxalone at 15 mg/kg provided rapid and reliable sedation, whereas alfaxalone administered at 100 mg/kg produced rapid and long lasting anesthesia.

  19. Dialysis and contrast media

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Thomsen, Henrik S.; Webb, Judith A.W.

    2002-01-01

    In a previous survey we revealed uncertainty among responders about (a) whether or not to perform hemodialysis in patients with severely reduced renal function who had received contrast medium; and (b) when to perform hemodialysis in patients on regular treatment with hemodialysis or continuous ambulatory dialysis who received contrast medium. Therefore, the Contrast Media Safety Committee of The European Society of Urogenital Radiology decided to review the literature and to issue guidelines. The committee performed a Medline search. Based on this, a report and guidelines were prepared. The report was discussed at the Ninth European Symposium on Urogenital Radiology in Genoa, Italy. Hemodialysis and peritoneal dialysis safely remove both iodinated and gadolinium-based contrast media. The effectiveness of hemodialysis depends on many factors including blood and dialysate flow rate, permeability of dialysis membrane, duration of hemodialysis and molecular size, protein binding, hydrophilicity, and electrical charge of the contrast medium. Generally, several hemodialysis sessions are needed to removal all contrast medium, whereas it takes 3 weeks for continuous ambulatory dialysis to remove the agent completely. There is no need to schedule the dialysis in relation to the injection of iodinated or MR contrast media or the injection of contrast agent in relation to the dialysis program. Hemodialysis does not protect poorly functioning kidneys against contrast-medium-induced nephrotoxicity. Simple guidelines are given. (orig.)

  20. Intravascular near-infrared fluorescence molecular imaging of atherosclerosis: toward coronary arterial visualization of biologically high-risk plaques

    Science.gov (United States)

    Calfon, Marcella A.; Vinegoni, Claudio; Ntziachristos, Vasilis; Jaffer, Farouc A.

    2010-01-01

    New imaging methods are urgently needed to identify high-risk atherosclerotic lesions prior to the onset of myocardial infarction, stroke, and ischemic limbs. Molecular imaging offers a new approach to visualize key biological features that characterize high-risk plaques associated with cardiovascular events. While substantial progress has been realized in clinical molecular imaging of plaques in larger arterial vessels (carotid, aorta, iliac), there remains a compelling, unmet need to develop molecular imaging strategies targeted to high-risk plaques in human coronary arteries. We present recent developments in intravascular near-IR fluorescence catheter-based strategies for in vivo detection of plaque inflammation in coronary-sized arteries. In particular, the biological, light transmission, imaging agent, and engineering principles that underlie a new intravascular near-IR fluorescence sensing method are discussed. Intravascular near-IR fluorescence catheters appear highly translatable to the cardiac catheterization laboratory, and thus may offer a new in vivo method to detect high-risk coronary plaques and to assess novel atherosclerosis biologics.

  1. Contrast analysis : A tutorial

    NARCIS (Netherlands)

    Haans, A.

    2018-01-01

    Contrast analysis is a relatively simple but effective statistical method for testing theoretical predictions about differences between group means against the empirical data. Despite its advantages, contrast analysis is hardly used to date, perhaps because it is not implemented in a convenient

  2. Intravascular Immune Surveillance by CXCR6+ NKT Cells Patrolling Liver Sinusoids

    Directory of Open Access Journals (Sweden)

    Geissmann Frederic

    2005-01-01

    Full Text Available We examined the in vivo behavior of liver natural killer T cells (NKT cells by intravital fluorescence microscopic imaging of mice in which a green fluorescent protein cDNA was used to replace the gene encoding the chemokine receptor CXCR6. NKT cells, which account for most CXCR6+ cells in liver, were found to crawl within hepatic sinusoids at 10-20 µm/min and to stop upon T cell antigen receptor activation. CXCR6-deficient mice exhibited a selective and severe reduction of CD1d-reactive NKT cells in the liver and decreased susceptibility to T-cell-dependent hepatitis. CXCL16, the cell surface ligand for CXCR6, is expressed on sinusoidal endothelial cells, and CXCR6 deficiency resulted in reduced survival, but not in altered speed or pattern of patrolling of NKT cells. Thus, NKT cells patrol liver sinusoids to provide intravascular immune surveillance, and CXCR6 contributes to liver-based immune responses by regulating their abundance.

  3. Orbital Atherectomy Plaque Modification Assessment of the Femoropopliteal Artery Via Intravascular Ultrasound (TRUTH Study).

    Science.gov (United States)

    Babaev, Anvar; Zavlunova, Susanna; Attubato, Michael J; Martinsen, Brad J; Mintz, Gary S; Maehara, Akiko

    2015-10-01

    The Tissue Removal Assessment with Ultrasound of the SFA and Popliteal (TRUTH) study assessed the performance of the orbital atherectomy system (OAS) to treat femoropopliteal arteries, including determining its effect on plaque removal. Patients with symptomatic femoropopliteal peripheral arterial disease were treated with the OAS followed by adjunctive balloon angioplasty (BA). Intravascular ultrasound (IVUS) images were collected pre- and post-OAS and post-OAS BA. Patients were followed through 12 months post-procedure. Twenty-nine lesions were treated with OAS-BA in 25 patients. The mean maximum balloon inflation pressure was 5.2 ± 1.2 atm. Virtual histology IVUS (VH-IVUS) analysis revealed at the maximum calcium ablation site that calcium reduction was responsible for 86% of the lumen area increase. The minimum lumen area increased from 4.0 mm(2) to 9.1 mm(2) (<.0001), and the percentage of area stenosis decreased from 76.9% to 43.0% (<.0001) after OAS-BA. At 12 months, the target lesion revascularization rate was 8.2%, and ankle-brachial index and Rutherford classification improved significantly from baseline through follow-up. The VH-IVUS analysis reveals that OAS modifies the calcified component of the plaque burden. It is hypothesized that calcium modification by OAS changes the lesion compliance, allowing for low pressure adjunctive BA. The clinical outcomes were favorable through 12-month follow-up. © The Author(s) 2015.

  4. Impact of peri-stent remodeling on restenosis: a volumetric intravascular ultrasound study.

    Science.gov (United States)

    Nakamura, M; Yock, P G; Bonneau, H N; Kitamura, K; Aizawa, T; Tamai, H; Fitzgerald, P J; Honda, Y

    2001-05-01

    Vessel remodeling is an important mechanism of late lumen loss after nonstent coronary interventions. However, its impact on in-stent restenosis has not been systematically investigated. Serial volumetric intravascular ultrasound analyses (poststent and follow-up) were performed in 55 lesions treated with a balloon-expandable stent (ACS MultiLink) using standard stent deployment techniques. The vessel volume (VV), lumen volume (LV), and volume bordered by the stent (SV) were measured using Simpson's method. The volume of plaque and neointima outside the stent (peri-stent volume, PSV) and volume of neointima within the stent (intrastent volume) were also measured. The change of each parameter during the follow-up period (follow-up minus poststent) was calculated and then divided by SV to normalize these values (designated as percent change [%]). As expected, %PSV directly correlated with %VV (Pexterior to a coronary stent occurs to a variable degree after stent implantation. There is a distinct trade-off between positive remodeling and in-stent hyperplasia: in segments in which the degree of peri-stent remodeling is less, intrastent neointimal proliferation is greater and accompanied by more significant late lumen loss.

  5. Transcatheter Arterial Embolization for Postpartum Hemorrhage with Disseminated Intravascular Coagulation: Outcome Assessment

    Energy Technology Data Exchange (ETDEWEB)

    An, Eun Jung; Kim, Young Hwan; Kwon, Bo Ra; Kim, See Hyung [Dept. of Radiology, Dongsan Medical Center, Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2011-12-15

    We evaluated the efficacy and predictors of clinical outcome after transcatheter arterial embolization (TAE) for treatment of postpartum hemorrhage with disseminated intravascular coagulation (DIC). Of 127 patients who underwent TAE for postpartum hemorrhage, 46 progressed to DIC (group 1), 81 showed normal range hematological parameters (group 2). We retrospectively evaluated etiology, embolization methods and the efficacy of TAE for intergroup comparison Pearson Chi-Square test and logistic regression model. Overall TAE failed to control bleeding in 9 patients in spite of technical success. Lower bleeding control rate was found in group 2 (82.6%) relative to group 1 (98.8%, p = 0.001). And embolization methods were not statistically different between two groups no statistically significant predictors associated with failed hemostasis except the amount of transfusion in group 1. Although bleeding control rate is lower in postpartum hemorrhage with DIC than without DIC, we believe that TAE with correction of DIC is an effective method for postpartum hemorrhage with DIC.

  6. Transcatheter Arterial Embolization for Postpartum Hemorrhage with Disseminated Intravascular Coagulation: Outcome Assessment

    International Nuclear Information System (INIS)

    An, Eun Jung; Kim, Young Hwan; Kwon, Bo Ra; Kim, See Hyung

    2011-01-01

    We evaluated the efficacy and predictors of clinical outcome after transcatheter arterial embolization (TAE) for treatment of postpartum hemorrhage with disseminated intravascular coagulation (DIC). Of 127 patients who underwent TAE for postpartum hemorrhage, 46 progressed to DIC (group 1), 81 showed normal range hematological parameters (group 2). We retrospectively evaluated etiology, embolization methods and the efficacy of TAE for intergroup comparison Pearson Chi-Square test and logistic regression model. Overall TAE failed to control bleeding in 9 patients in spite of technical success. Lower bleeding control rate was found in group 2 (82.6%) relative to group 1 (98.8%, p = 0.001). And embolization methods were not statistically different between two groups no statistically significant predictors associated with failed hemostasis except the amount of transfusion in group 1. Although bleeding control rate is lower in postpartum hemorrhage with DIC than without DIC, we believe that TAE with correction of DIC is an effective method for postpartum hemorrhage with DIC.

  7. Hyperkalemia after irradiation of packed red blood cells: Possible effects with intravascular fetal transfusion

    International Nuclear Information System (INIS)

    Thorp, J.A.; Plapp, F.V.; Cohen, G.R.; Yeast, J.D.; O'Kell, R.T.; Stephenson, S.

    1990-01-01

    Plasma potassium, calcium, and albumin concentrations in irradiated blood, and in fetal blood before and after transfusion, were measured. Dangerously high plasma potassium levels were observed in some units of irradiated packed red blood cells (range, 13.9 to 66.5 mEq/L; mean, 44.7 mEq/L) and could be one possible explanation for the high incidence of fetal arrhythmia associated with fetal intravascular transfusion. There are many factors operative in the preparation of irradiated packed red blood cells that may predispose to high potassium levels: the age of the red blood cells, the number of procedures used to concentrate the blood, the duration of time elapsed from concentration, the duration of time elapsed from irradiation, and the hematocrit. Use of fresh blood, avoidance of multiple packing procedures, limiting the hematocrit in the donor unit to less than or equal to 80%, and minimizing the time between concentration, irradiation and transfusion may minimize the potassium levels, and therefore making an additional washing procedure unnecessary

  8. Protein Z efficiently depletes thrombin generation in disseminated intravascular coagulation with poor prognosis.

    Science.gov (United States)

    Lee, Nuri; Kim, Ji-Eun; Gu, Ja-Yoon; Yoo, Hyun Ju; Kim, Inho; Yoon, Sung-Soo; Park, Seonyang; Han, Kyou-Sup; Kim, Hyun Kyung

    2016-01-01

    Disseminated intravascular coagulation (DIC) is characterized by consumption of coagulation factors and anticoagulants. Thrombin generation assay (TGA) gives useful information about global hemostatic status. We developed a new TGA system that anticoagulant addition can deplete thrombin generation in plasma, which may reflect defective anticoagulant system in DIC. TGAs were measured on the calibrated automated thrombogram with and without thrombomodulin or protein Z in 152 patients who were suspected of having DIC, yielding four parameters including lag time, endogenous thrombin potential, peak thrombin and time-to-peak in each experiment. Nonsurvivors showed significantly prolonged lag time and time-to-peak in TGA-protein Z system, which was performed with added protein Z. In multivariate Cox regression analysis, lag time and time-to-peak in TGA system were significant independent prognostic factors. In TGA-protein Z system, lag time and time-to-peak were revealed as independent prognostic factors of DIC. Protein Z addition could potentiate its anticoagulant effect in DIC with poor prognosis, suggesting the presence of defective protein Z system. The prolonged lag time and time-to-peak in both TGA and TGA-protein Z systems are expected to be used as independent prognostic factors of DIC.

  9. TWO NOVEL ACM (ACTIVE CONTOUR MODEL) METHODS FOR INTRAVASCULAR ULTRASOUND IMAGE SEGMENTATION

    International Nuclear Information System (INIS)

    Chen, Chi Hau; Potdat, Labhesh; Chittineni, Rakesh

    2010-01-01

    One of the attractive image segmentation methods is the Active Contour Model (ACM) which has been widely used in medical imaging as it always produces sub-regions with continuous boundaries. Intravascular ultrasound (IVUS) is a catheter based medical imaging technique which is used for quantitative assessment of atherosclerotic disease. Two methods of ACM realizations are presented in this paper. The gradient descent flow based on minimizing energy functional can be used for segmentation of IVUS images. However this local operation alone may not be adequate to work with the complex IVUS images. The first method presented consists of basically combining the local geodesic active contours and global region-based active contours. The advantage of combining the local and global operations is to allow curves deforming under the energy to find only significant local minima and delineate object borders despite noise, poor edge information and heterogeneous intensity profiles. Results for this algorithm are compared to standard techniques to demonstrate the method's robustness and accuracy. In the second method, the energy function is appropriately modified and minimized using a Hopfield neural network. Proper modifications in the definition of the bias of the neurons have been introduced to incorporate image characteristics. The method overcomes distortions in the expected image pattern, such as due to the presence of calcium, and employs a specialized structure of the neural network and boundary correction schemes which are based on a priori knowledge about the vessel geometry. The presented method is very fast and has been evaluated using sequences of IVUS frames.

  10. Intravascular optical imaging of high-risk plaques in vivo by targeting macrophage mannose receptors

    Science.gov (United States)

    Kim, Ji Bak; Park, Kyeongsoon; Ryu, Jiheun; Lee, Jae Joong; Lee, Min Woo; Cho, Han Saem; Nam, Hyeong Soo; Park, Ok Kyu; Song, Joon Woo; Kim, Tae Shik; Oh, Dong Joo; Gweon, Daegab; Oh, Wang-Yuhl; Yoo, Hongki; Kim, Jin Won

    2016-03-01

    Macrophages mediate atheroma expansion and disruption, and denote high-risk arterial plaques. Therefore, they are substantially gaining importance as a diagnostic imaging target for the detection of rupture-prone plaques. Here, we developed an injectable near-infrared fluorescence (NIRF) probe by chemically conjugating thiolated glycol chitosan with cholesteryl chloroformate, NIRF dye (cyanine 5.5 or 7), and maleimide-polyethylene glycol-mannose as mannose receptor binding ligands to specifically target a subset of macrophages abundant in high-risk plaques. This probe showed high affinity to mannose receptors, low toxicity, and allowed the direct visualization of plaque macrophages in murine carotid atheroma. After the scale-up of the MMR-NIRF probe, the administration of the probe facilitated in vivo intravascular imaging of plaque inflammation in coronary-sized vessels of atheromatous rabbits using a custom-built dual-modal optical coherence tomography (OCT)-NIRF catheter-based imaging system. This novel imaging approach represents a potential imaging strategy enabling the identification of high-risk plaques in vivo and holds promise for future clinical implications.

  11. Optimization of dual-wavelength intravascular photoacoustic imaging of atherosclerotic plaques using Monte Carlo optical modeling

    Science.gov (United States)

    Dana, Nicholas; Sowers, Timothy; Karpiouk, Andrei; Vanderlaan, Donald; Emelianov, Stanislav

    2017-10-01

    Coronary heart disease (the presence of coronary atherosclerotic plaques) is a significant health problem in the industrialized world. A clinical method to accurately visualize and characterize atherosclerotic plaques is needed. Intravascular photoacoustic (IVPA) imaging is being developed to fill this role, but questions remain regarding optimal imaging wavelengths. We utilized a Monte Carlo optical model to simulate IVPA excitation in coronary tissues, identifying optimal wavelengths for plaque characterization. Near-infrared wavelengths (≤1800 nm) were simulated, and single- and dual-wavelength data were analyzed for accuracy of plaque characterization. Results indicate light penetration is best in the range of 1050 to 1370 nm, where 5% residual fluence can be achieved at clinically relevant depths of ≥2 mm in arteries. Across the arterial wall, fluence may vary by over 10-fold, confounding plaque characterization. For single-wavelength results, plaque segmentation accuracy peaked at 1210 and 1720 nm, though correlation was poor (blood, a primary and secondary wavelength near 1210 and 1350 nm, respectively, may offer the best implementation of dual-wavelength IVPA imaging. These findings could guide the development of a cost-effective clinical system by highlighting optimal wavelengths and improving plaque characterization.

  12. Persistent lesion hyperintensity on brain diffusion-weighted MRI is an early sign of intravascular lymphoma.

    Science.gov (United States)

    Kageyama, Takashi; Yamanaka, Haruo; Nakamura, Fumihiko; Suenaga, Toshihiko

    2017-06-08

    A 63-year-old man presented with right-sided hemianopia and unsteady gait. Brain MRI revealed multiple hyperintense infarct-like lesions on diffusion-weighted images (DWI). Hyperintensity persisted in some of these lesions even after 6 weeks, although his symptoms were ameliorated then. The patient developed episodic dizziness and a transient event of apraxia at 18 weeks after the first episode. Brain MRI revealed additional hyperintense lesions on DWI, which persisted even after 7 weeks. Eventually, the patient manifested cauda equina syndrome 39 weeks after the first episode. Brain MRI showed the presence of new lesions in addition to the persistent hyperintense lesions on DWI over 21 weeks in the right frontal lobe. Based on laboratory findings and the pathological assessment of bone marrow and random skin biopsies, the patient was diagnosed with intravascular lymphoma (IVL). Persistent hyperintense lesions on DWI of brain MRI may precede the clinical exacerbation of IVL. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Risk of disseminated intravascular coagulation in patients undergoing US-guided transperineal prostatic biopsy

    International Nuclear Information System (INIS)

    Stella, M.S.; Comparato, D.; Camici, M.; Evangelisti, L.; Gaudio, V.; De Negri, F.; Talarico, L.; Giusti, C.; Morelli, G.

    1991-01-01

    Disseminated intravascular coagulation (DIC) is a severe life-threatening acute bleeding disorder. Traumatized tissues, tumors, necrotic tissues, or bacterial endotoxines release similar material in the blood to the tissutal factors activating the coagulation cascade. This preliminary study was aimed at verifying the risk of DIV in patients undergoing US-guided transperineal prostatic biopsy with Chiba and Tru-Cut needles. To evaluate the activation degree of coagulation factors in the circulation, the authors measured the concentrations of urinary fibrin degradation products in 10 patients undergoing US-guided transperineal prostatic biopsy, both before and after biopsy, every second hour, for 24 hours. Every tube of urine sample contained soya bean trypsin inhibitor and bovine thrombin to prevent any further fibrin degradation during incubation period for the possible presence of blood in urine samples. The results showed that 7/10 patients had marked increase in urinary fibrin degradation product levels (up to 800 XXXX%), with a 3-phase trend: early peak after 2-6 hours, middle peak after 6-14 hours, and late peak after 18-24 hours, which proved the activation of the coagulation cascade

  14. CT virtual intravascular endoscopy assessment of coronary artery plaques: A preliminary study

    International Nuclear Information System (INIS)

    Sun Zhonghua; Dimpudus, Franky Jacobus; Nugroho, Johanes; Adipranoto, Jeffrey Daniel

    2010-01-01

    Purpose: The purpose of this study was to investigate the potential value of CT virtual intravascular endoscopy (VIE) in the visualization and assessment of coronary plaques in patients suspected of coronary artery disease. Materials and methods: 20 (13 men, 7 women, mean age 54 years) consecutive patients with suspected coronary artery disease undergoing 64-slice CT angiography were included in the study. Four main coronary artery branches were assessed with regard to the presence of coronary plaques based on 2D axial, multiplanar reformation, 3D volume rendering and VIE visualizations. The coronary plaques were characterized into calcified, noncalcified and mixed plaques. The intraluminal appearances of these coronary plaques were demonstrated with VIE images and correlated with 2D and 3D images to determine the diagnostic value of VIE for the assessment of the plaques. Results: VIE was able to identify and demonstrate the intraluminal appearances of coronary plaques in 18 patients involving 32 coronary artery branches which were shown as an irregularly intraluminal protruding sign in extensively calcified plaques and smooth protruding appearance in noncalcified or focally calcified plaques. An irregular intraluminal appearance was also noticed in the presence of mixed plaques due to variable components with different CT attenuations contained within the plaques. VIE accurately confirmed the degree of coronary stenosis or occlusion despite the presence of heavy calcification. Conclusion: VIE could be used as a complementary tool to conventional CT visualizations for the analysis of luminal changes and assessment of disease extent caused by the coronary plaques.

  15. Indium-111-oxine labeled platelet scintigraphy for detection of intracardiac and intravascular thrombi

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Michio; Ojima, Kenji; Tsuda, Takashi [Niigata Univ. (Japan). School of Medicine

    1983-09-01

    This study was designed to evaluate the efficacy of scintigraphy by using /sup 111/In-oxine labeled platelets for the detection of either intracardiac or intravascular thrombi. Fourteen cases of thrombi diagnosed or suspected on the basis of either angiography or two-dimensional echography were examined. They included four cases of left ventricular thrombi, three of left atrial thrombi, four of vascular thrombi and three of inflammatory disease. Platelet samples from the patients were labeled by /sup 111/In-oxine according to the method originated by Yui et al. The labeling efficiency was 72.4+-9.8%. The platelets retained good function except for collagen aggregability. Hot areas of high quality in the scintigram were demonstrated in six cases including two with left ventricular thrombi, two with left atrial thrombi and two with vascular thrombi. These areas accorded well with the findings of angiography, echography or surgery. The removed thrombi had a layer of aggregated platelets on the surface. Platelet survival was shortened in a case of prosthetic valve endocarditis without a hot area, and was normal in four out of the five cases including two with a hot area. It is concluded that this method is potentially predictive in detecting thrombi.

  16. Development of an intravascular ultrasound elastography based on a dual-element transducer

    Science.gov (United States)

    Shih, Cho-Chiang; Chen, Pei-Yu; Ma, Teng; Zhou, Qifa; Shung, K. Kirk; Huang, Chih-Chung

    2018-04-01

    The ability to measure the elastic properties of plaques and vessels would be useful in clinical diagnoses, particularly for detecting a vulnerable plaque. This study demonstrates the feasibility of the combination of intravascular ultrasound (IVUS) and acoustic radiation force elasticity imaging for detecting the distribution of stiffness within atherosclerotic arteries ex vivo. A dual-frequency IVUS transducer with two elements was used to induce the propagation of the shear wave (by the 8.5 MHz pushing element) which could be simultaneously monitored by the 31 MHz imaging element. The wave-amplitude image and the wave-velocity image were reconstructed by measuring the peak displacement and wave velocity of shear wave propagation, respectively. System performance was verified using gelatin phantoms. The phantom results demonstrate that the stiffness differences of shear modulus of 1.6 kPa can be distinguished through the wave-amplitude and wave-velocity images. The stiffness distributions of the atherosclerotic aorta from a rabbit were obtained, for which the values of peak displacement and the shear wave velocity were 3.7 ± 1.2 µm and 0.38 ± 0.19 m s-1 for the lipid-rich plaques, and 1.0 ± 0.2 µm and 3.45 ± 0.45 m s-1 for the arterial walls, respectively. These results indicate that IVUS elasticity imaging can be used to distinguish the elastic properties of plaques and vessels.

  17. Intravascular application of electrocautery in a rabbit model of abdominal aortic endarterectomy.

    Science.gov (United States)

    Wang, Chuan; Xin, Yi; Li, Na; Li, Diankun; Li, Jingxing; Gu, Chengxiong

    2017-07-01

    Effective therapies for preventing perioperative complications such as thrombosis and inflammation after coronary endarterectomy (CE) are lacking. Electrocoagulation electrotomes have been routinely used in surgery for their cutting, clotting, and hemostatic properties. As strong flattening tools, their electrocautery function may prevent mechanical intimal-adventitial injury to arterial circulation and attenuate stenosis. The present study investigated the effects of intravascular application of electrocautery on ameliorating inflammation and thrombosis in a rabbit model of abdominal aortic endarterectomy. New Zealand rabbits were randomly divided into the sham, control (endarterectomy), and study (endarterectomy + electrocautery) groups with 10 in each group. Abdominal aortas were partially blocked and intima was removed. Electrocautery was performed with an electrocoagulation electrotome through the entire blocked vessel lumen. Vascular ultrasound parameters, molecular biological and histological characteristics of the abdominal aorta including vascular diameter, blood flow velocity, serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels, and apoptosis rate of vascular endothelial cells (ECs) were evaluated postoperatively by vascular Doppler ultrasound, ELISA, real-time RT-PCR, flow cytometry, and immunofluorescence at various time points. Compared with the endarterectomy + electrocautery group, the isolated endarterectomy group had significantly increased levels and gene expression of TNF-α and IL-6 (Pelectrocautery has favorable short-term effects on the abdominal aorta and can reduce inflammation in a rabbit model of abdominal aorta endarterectomy. Long-term anti-inflammatory and anti-thrombotic effects on arterial remodeling and the clinical value of electrocautery in CE remain to be determined.

  18. Validating Intravascular Imaging with Serial Optical Coherence Tomography and Confocal Fluorescence Microscopy.

    Science.gov (United States)

    Tardif, Pier-Luc; Bertrand, Marie-Jeanne; Abran, Maxime; Castonguay, Alexandre; Lefebvre, Joël; Stähli, Barbara E; Merlet, Nolwenn; Mihalache-Avram, Teodora; Geoffroy, Pascale; Mecteau, Mélanie; Busseuil, David; Ni, Feng; Abulrob, Abedelnasser; Rhéaume, Éric; L'Allier, Philippe; Tardif, Jean-Claude; Lesage, Frédéric

    2016-12-15

    Atherosclerotic cardiovascular diseases are characterized by the formation of a plaque in the arterial wall. Intravascular ultrasound (IVUS) provides high-resolution images allowing delineation of atherosclerotic plaques. When combined with near infrared fluorescence (NIRF), the plaque can also be studied at a molecular level with a large variety of biomarkers. In this work, we present a system enabling automated volumetric histology imaging of excised aortas that can spatially correlate results with combined IVUS/NIRF imaging of lipid-rich atheroma in cholesterol-fed rabbits. Pullbacks in the rabbit aortas were performed with a dual modality IVUS/NIRF catheter developed by our group. Ex vivo three-dimensional (3D) histology was performed combining optical coherence tomography (OCT) and confocal fluorescence microscopy, providing high-resolution anatomical and molecular information, respectively, to validate in vivo findings. The microscope was combined with a serial slicer allowing for the imaging of the whole vessel automatically. Colocalization of in vivo and ex vivo results is demonstrated. Slices can then be recovered to be tested in conventional histology.

  19. Reversible Hypopituitarism Associated with Intravascular Large B-Cell Lymphoma: Case Report of Successful Immunochemotherapy.

    Science.gov (United States)

    Sawada, Yusuke; Ishii, Sumiyasu; Koga, Yasuhiko; Tomizawa, Taku; Matsui, Ayako; Tomaru, Takuya; Ozawa, Atsushi; Shibusawa, Nobuyuki; Satoh, Tetsurou; Shimizu, Hiroaki; Hirato, Junko; Yamada, Masanobu

    2016-03-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of diffuse large B-cell lymphoma. There have been only a limited number of reports regarding pituitary dysfunction associated with IVLBCL. We present a 71-year-old woman with hypopituitarism without any hypothalamic/pituitary abnormalities as assessed by magnetic resonance imaging. She presented with edema, abducens palsy, and elevated levels of lactate dehydrogenase and soluble interleukin-2 receptor. Provocative testing showed that the peaks of luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone and adrenocorticotropic hormone were evoked to normal levels by simultaneous administration of luteinizing hormone-releasing hormone, thyrotropin-releasing hormone and corticotropin-releasing hormone, but the responses of these four pituitary hormones showed a delayed pattern. She was diagnosed with IVLBCL with cerebrospinal invasion by pathological findings of the bone marrow, skin, and cerebrospinal fluid. She achieved hematological remission after immunochemotherapy. Pituitary function was also restored without hormonal replacement, and the improvement of the pituitary function was confirmed by dynamic testing. We reviewed the literature with respect to hypopituitarism associated with IVLBCL. There were less than 20 case reports and most of the patients died. Endocrinological course was described in only two cases, and both of them required hormonal supplementation. To our knowledge, this is the first case of hypopituitarism induced by IVLBCL that was successfully managed by immunochemotherapy alone. This case suggests that early diagnosis and treatment of IVLBCL might improve anterior pituitary function and enable patients to avoid hormone replacement therapy.

  20. Contrast agents for MRI

    International Nuclear Information System (INIS)

    Bonnemain, B.

    1994-01-01

    Contrast agents MRI (Magnetic Resonance Imaging) have been developed to improve the diagnostic information obtained by this technic. They mainly interact on T1 and T2 parameters and increase consequently normal to abnormal tissues contrast. The paramagnetic agents which mainly act on longitudinal relaxation rate (T1) are gadolinium complexes for which stability is the main parameter to avoid any release of free gadolinium. The superparamagnetic agents that decrease signal intensity by an effect on transversal relaxation rate (T2) are developed for liver, digestive and lymph node imaging. Many area of research are now opened for optimal use of present and future contrast agents in MRI. (author). 28 refs., 4 tabs

  1. Compressive Phase Contrast Tomography

    International Nuclear Information System (INIS)

    Maia, Filipe; MacDowell, Alastair; Marchesini, Stefano; Padmore, Howard A.; Parkinson, Dula Y.; Pien, Jack; Schirotzek, Andre; Yang, Chao

    2010-01-01

    When x-rays penetrate soft matter, their phase changes more rapidly than their amplitude. Interference effects visible with high brightness sources creates higher contrast, edge enhanced images. When the object is piecewise smooth (made of big blocks of a few components), such higher contrast datasets have a sparse solution. We apply basis pursuit solvers to improve SNR, remove ring artifacts, reduce the number of views and radiation dose from phase contrast datasets collected at the Hard X-Ray Micro Tomography Beamline at the Advanced Light Source. We report a GPU code for the most computationally intensive task, the gridding and inverse gridding algorithm (non uniform sampled Fourier transform).

  2. Generalized Phase Contrast

    CERN Document Server

    Glückstad, Jesper

    2009-01-01

    Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast (GPC) method including an overview of the range of current and potential applications of GPC in wavefront sensing and phase imaging, structured laser illumination and image projection, optical trapping and manipulation, and optical encryption and decryption. The GPC method goes further than the restrictive assumptions of conventional Zernike phase contrast analysis and achieves an expanded range of validity beyond weak phase perturbations. The generalized analysis yields design criteria for tuning experimental parameters to achieve optimal performance in terms of accuracy, fidelity and light efficiency. Optimization can address practical issues, such as finding an optimal spatial filter for the chosen application, ...

  3. Mamografia Espectral de Contraste

    OpenAIRE

    Martins, Inês Santiago; Pereira, Inês; Pacheco, Hugo Pisco; Moutinho, Leonor

    2014-01-01

    A mamografia de contraste é uma aplicação recente possível com a mamografia digital directa, que utiliza contraste iodado endovenoso tendo como princípio a neovascularização induzida no cancro da mama, permitindo obter informação morfológica e funcional. Na mamografia espectral de contraste realiza-se uma aquisição simultânea com alta e baixa energia para cada incidência após administração de contraste iodado endovenoso. É depois feita uma imagem recombinada em que são realçadas as áreas que ...

  4. Aspiration of Barium Contrast

    OpenAIRE

    Fuentes Santos, Cristina; Steen, Bárbara

    2014-01-01

    The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical fil...

  5. Formation of potential antigens from radiographic contrast media

    International Nuclear Information System (INIS)

    Nilsson, R.; Ehrenberg, L.; Fedorcsak, I.

    1987-01-01

    The use of radiographic contrast media is occasionally accompanied by more or less serious adverse effects, evidently of complex etiology, following intravascular administration. Some of these reactions are suspected of having an allergic basis. The in vitro and in vivo formation of iodinated serum proteins following gamma irradiation in the presence of two commonly used radiographic contrast media is demonstrated. Non-toxic concentrations of ascorbate present during the irradiation is shown to prevent the formation of such iodo-proteins in vitro as well as in vivo. The amounts of potentially antigenic iodoprotein formed during radiographic procedures will certainly be very small, but this quantity may be sufficient to elicit a hypersensitivity reaction in cases when an individual has been previously sensitized to immunologically similar iodo-proteins, a mechanism that could account for certain rare and unpredictable reations. The radiation induced formation of iodo-proteins may also serve as a model for the formation of iodine containing antigens mediated by a free radical mechanism, i.e. in the metabolism of iodinated compounds like erythrosine, a widely used colouring agent for certain foods. (orig.)

  6. Angioplasty Guided by Intravascular Ultrasound: Meta-Analysis of Randomized Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, José Albuquerque Neto de, E-mail: jafneto@cardiol.br; Nogueira, Iara Antonia Lustosa [Universidade Federal do Maranhão, São Luiz, MA (Brazil); Figueiro, Mabel Fernandes; Buehler, Anna Maria; Berwanger, Otavio [Instituto de Ensino e Pesquisa do Hospital do Coração, São Paulo, SP (Brazil)

    2013-08-15

    The impact of intravascular ultrasound (IVUS) use on stenting has shown inconclusive results. Systematic review and meta-analysis of the impact of IVUS on stenting regarding the clinical and angiographic evolution. A search was performed in Medline/Pubmed, CENTRAL, Embase, Lilacs, Scopus and Web of Science databases. It included randomized clinical trials (RCTs) that evaluated the implantation of stents guided by IVUS, compared with those using angiography alone (ANGIO). The minimum follow-up duration was six months and the following outcomes were assessed: thrombosis, mortality, myocardial infarction, percutaneous and surgical revascularization, major adverse cardiovascular events (MACE) and restenosis. The binary outcomes were presented considering the number of events in each group; the estimates were generated by a random effects model, considering Mantel-Haenszel statistics as weighting agent and magnitude of effect for the relative risk (RR) with its respective 95% confidence interval (95%CI). Higgins I{sup 2} test was used to quantify the consistency between the results of each study. A total of 2,689 articles were evaluated, including 8 RCTs. There was a 27% reduction in angiographic restenosis (RR: 0.73, 95% CI: 0.54-0.97, I{sup 2} = 51%) and statistically significant reduction in the rates of percutaneous revascularization and overall (RR: 0.88; 95% CI: 0.51 to 1.53, I{sup 2} = 61%, RR: 0.73, 95% CI: 0.54 to 0.99, I{sup 2} = 55%), with no statistical difference in surgical revascularization (RR: 0.95, 95% CI: 0.52-1.74, I{sup 2} = 0%) in favor of IVUS vs. ANGIO. There were no differences regarding the other outcomes in the comparison between the two strategies. Angioplasty with stenting guided by IVUS decreases the rates of restenosis and revascularization, with no impact on MACE, acute myocardial infarction, mortality or thrombosis outcomes.

  7. Polymer-coated albumin microspheres as carriers for intravascular tumour targeting of cisplatin.

    Science.gov (United States)

    Verrijk, R; Smolders, I J; McVie, J G; Begg, A C

    1991-01-01

    We used a poly-lactide-co-glycolide polymer (PLAGA 50:50) to formulate cisplatin (cDDP) into microspheres designed for intravascular administration. Two systems were developed. PLAGA-coated albumin microspheres and microspheres consisting of PLAGA only. PLAGA-coated microspheres displayed a mean diameter of 31.8 +/- 0.9 microns and a payload of 7.5% cDDP (w/w). Solid PLAGA microspheres exhibited a mean diameter of 19.4 +/- 0.6 microns and a payload of 20% cDDP. Release characteristics and in vitro effects on L1210 leukemia and B16 melanoma cell lines were investigated. Both types of microsphere overcame the initial rapid release of cDDP (burst effect), and PLAGA-coated albumin microspheres also showed a lag phase of approximately 30 min before cDDP release began. PLAGA-coated albumin microspheres released most of their payload through diffusion, and the coating eventually cracked after 7 days' incubation in saline supplemented with 0.1% Tween at 37 degrees C, enabling the release of any cDDP remaining. Effects of platinum, pre-released from PLAGA-coated albumin microspheres on the in vitro growth of L1210 cells were comparable with those of standard formulations (dissolved) of cDDP. Material released from non-drug-loaded PLAGA microspheres had no effect on L1210 cell growth, suggesting the absence of cytotoxic compounds in the matrix. The colony-forming ability of B16 cells was also equally inhibited by standard cDDP and pre-released drug. These studies show that formulation of cDDP in PLAGA-based microspheres prevents the rapid burst effect of cDDP seen in previous preparations and offers an improved system of administration for hepatic artery infusion or adjuvant therapy, enabling better clinical handling and the promise of a higher ratio of tumour tissue to normal tissue.

  8. Intravascular ultrasound evaluation of JETSTREAM atherectomy removal of superficial calcium in peripheral arteries.

    Science.gov (United States)

    Maehara, Akiko; Mintz, Gary S; Shimshak, Thomas M; Ricotta, Joseph J; Ramaiah, Venkatesh; Foster, Malcolm T; Davis, Thomas P; Gray, William A

    2015-05-01

    Endovascular treatment of calcified femoral-popliteal disease is challenging. We sought to evaluate the mechanism of lumen gain when using the JETSTREAM Atherectomy System to treat calcified peripheral artery lesions. The JETSTREAM Calcium Study was a prospective, single-arm, multicentre study to evaluate the JETSTREAM Atherectomy System for severely calcified femoral-popliteal artery lesions, i.e., patients with claudication and lesions with superficial calcium >90° and >5 mm in length as determined by intravascular ultrasound (IVUS). The 2.1 mm catheter was used in this study without distal protection. Fifty-five patients underwent angiographic screening: 26 (45%) met IVUS inclusion criteria. Angiographic calcium was moderate in eight cases and severe in 14, with no available data for four cases. Visual diameter stenosis was 86±9% pre-treatment, 37±13% post atherectomy, and 10±6% post adjunctive treatment (adjunctive PTA+stenting in eight and adjunct PTA alone in 16). IVUS showed lumen area increased from 6.6±3.7 mm2 to 10.0±3.6 mm2 (p=0.001): calcium reduction was responsible for 86±23% of the lumen increase. Although the superficial calcium arc did not change (151±70° to 146±71°, p=0.83), the arc of reverberation increased (23±20° to 65±40°, p=0.006), indicating device-related modification of calcium. Adjunctive balloon angioplasty was performed in 62% of the lesions, and stent implantation in 31%. In 11 cases with adjunctive balloon dilation, the MLA increased from 7.1 (6.4, 7.8) mm2 post atherectomy to 11.9 (10.3, 13.5) mm2 post balloon (pAtherectomy System increased lumen dimensions in moderately or severely calcified femoral-popliteal lesions by removing superficial calcium without major complications.

  9. Abnormal pulmonary artery stiffness in pulmonary arterial hypertension: in vivo study with intravascular ultrasound.

    Directory of Open Access Journals (Sweden)

    Edmund M T Lau

    Full Text Available BACKGROUND: There is increasing recognition that pulmonary artery stiffness is an important determinant of right ventricular (RV afterload in pulmonary arterial hypertension (PAH. We used intravascular ultrasound (IVUS to evaluate the mechanical properties of the elastic pulmonary arteries (PA in subjects with PAH, and assessed the effects of PAH-specific therapy on indices of arterial stiffness. METHOD: Using IVUS and simultaneous right heart catheterisation, 20 pulmonary segments in 8 PAH subjects and 12 pulmonary segments in 8 controls were studied to determine their compliance, distensibility, elastic modulus and stiffness index β. PAH subjects underwent repeat IVUS examinations after 6-months of bosentan therapy. RESULTS: AT BASELINE, PAH SUBJECTS DEMONSTRATED GREATER STIFFNESS IN ALL MEASURED INDICES COMPARED TO CONTROLS: compliance (1.50±0.11×10(-2 mm(2/mmHg vs 4.49±0.43×10(-2 mm(2/mmHg, p<0.0001, distensibility (0.32±0.03%/mmHg vs 1.18±0.13%/mmHg, p<0.0001, elastic modulus (720±64 mmHg vs 198±19 mmHg, p<0.0001, and stiffness index β (15.0±1.4 vs 11.0±0.7, p = 0.046. Strong inverse exponential associations existed between mean pulmonary artery pressure and compliance (r(2 = 0.82, p<0.0001, and also between mean PAP and distensibility (r(2 = 0.79, p = 0.002. Bosentan therapy, for 6-months, was not associated with any significant changes in all indices of PA stiffness. CONCLUSION: Increased stiffness occurs in the proximal elastic PA in patients with PAH and contributes to the pathogenesis RV failure. Bosentan therapy may not be effective at improving PA stiffness.

  10. Gadolinium neutron capture brachytherapy (GdNCB), a new treatment method for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Enger, Shirin A.; Rezaei, Arash; Munck af Rosenschoeld, Per; Lundqvist, Hans

    2006-01-01

    Restenosis is a major problem after balloon angioplasty and stent implantation. The aim of this study is to introduce gadolinium neutron capture brachytherapy (GdNCB) as a suitable modality for treatment of stenosis. The utility of GdNCB in intravascular brachytherapy (IVBT) of stent stenosis is investigated by using the GEANT4 and MCNP4B Monte Carlo radiation transport codes. To study capture rate, Kerma, absorbed dose and absorbed dose rate around a Gd-containing stent activated with neutrons, a 30 mm long, 5 mm diameter gadolinium foil is chosen. The input data is a neutron spectrum used for clinical neutron capture therapy in Studsvik, Sweden. Thermal neutron capture in gadolinium yields a spectrum of high-energy gamma photons, which due to the build-up effect gives an almost flat dose delivery pattern to the first 4 mm around the stent. The absorbed dose rate is 1.33 Gy/min, 0.25 mm from the stent surface while the dose to normal tissue is in order of 0.22 Gy/min, i.e., a factor of 6 lower. To spare normal tissue further fractionation of the dose is also possible. The capture rate is relatively high at both ends of the foil. The dose distribution from gamma and charge particle radiation at the edges and inside the stent contributes to a nonuniform dose distribution. This will lead to higher doses to the surrounding tissue and may prevent stent edge and in-stent restenosis. The position of the stent can be verified and corrected by the treatment plan prior to activation. Activation of the stent by an external neutron field can be performed days after catherization when the target cells start to proliferate and can be expected to be more radiation sensitive. Another advantage of the nonradioactive gadolinium stent is the possibility to avoid radiation hazard to personnel

  11. Exogenous normal lymph alleviates microcirculation disturbances and abnormal hemorheological properties in rats with disseminated intravascular coagulation

    International Nuclear Information System (INIS)

    Niu, Chun-Yu; Zhao, Zi-Gang; Zhang, Yu-Ping; Hou, Ya-Li; Li, Jun-Jie; Jiang, Hua; Zhang, Jing

    2013-01-01

    Disturbances of the microcirculation and abnormal hemorheological properties are important factors that play an important role in disseminated intravascular coagulation (DIC) and result in organ dysfunction or failure. In the present study, we established an animal model of DIC using intravenous Dextran 500 in rats, and used exogenous normal lymph corresponding to 1/15 of whole blood volume for injection through the left jugular vein. We found that normal lymph could improve the blood pressure and survival time of rats with DIC. The results regarding the mesenteric microcirculation showed that the abnormality of the diameter of mesenteric microvessels and micro-blood flow speed in the DIC+lymph group was significantly less than in the DIC+saline group. Whole blood viscosity, relative viscosity, plasma viscosity, hematocrit (Hct), erythrocyte sedimentation rate (ESR), and electrophoresis time of erythrocytes were significantly increased in the DIC+saline group compared to the control group. The electrophoretic length and migration of erythrocytes from the DIC+saline and DIC+lymph groups were significantly slower than the control group. Blood relative viscosity, Hct, ESR, and electrophoretic time of erythrocytes were significantly increased in the DIC+lymph group compared to the control group. Whole blood viscosity, relative viscosity and reduced viscosity were significantly lower in the DIC+lymph group than in the DIC+saline group, and erythrocyte deformability index was also significantly higher than in the DIC+saline and control groups. These results suggest that exogenous normal lymph could markedly improve the acute microcirculation disturbance and the abnormal hemorheological properties in rats with DIC induced by Dextran 500

  12. Exogenous normal lymph alleviates microcirculation disturbances and abnormal hemorheological properties in rats with disseminated intravascular coagulation

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Chun-Yu; Zhao, Zi-Gang; Zhang, Yu-Ping [Institute of Microcirculation, Hebei North University, Zhangjiakou (China); Hou, Ya-Li [Department of Clinical Laboratory, First Affiliated Hospital, Hebei North University, Zhangjiakou (China); Li, Jun-Jie; Jiang, Hua; Zhang, Jing [Institute of Microcirculation, Hebei North University, Zhangjiakou (China)

    2013-02-01

    Disturbances of the microcirculation and abnormal hemorheological properties are important factors that play an important role in disseminated intravascular coagulation (DIC) and result in organ dysfunction or failure. In the present study, we established an animal model of DIC using intravenous Dextran 500 in rats, and used exogenous normal lymph corresponding to 1/15 of whole blood volume for injection through the left jugular vein. We found that normal lymph could improve the blood pressure and survival time of rats with DIC. The results regarding the mesenteric microcirculation showed that the abnormality of the diameter of mesenteric microvessels and micro-blood flow speed in the DIC+lymph group was significantly less than in the DIC+saline group. Whole blood viscosity, relative viscosity, plasma viscosity, hematocrit (Hct), erythrocyte sedimentation rate (ESR), and electrophoresis time of erythrocytes were significantly increased in the DIC+saline group compared to the control group. The electrophoretic length and migration of erythrocytes from the DIC+saline and DIC+lymph groups were significantly slower than the control group. Blood relative viscosity, Hct, ESR, and electrophoretic time of erythrocytes were significantly increased in the DIC+lymph group compared to the control group. Whole blood viscosity, relative viscosity and reduced viscosity were significantly lower in the DIC+lymph group than in the DIC+saline group, and erythrocyte deformability index was also significantly higher than in the DIC+saline and control groups. These results suggest that exogenous normal lymph could markedly improve the acute microcirculation disturbance and the abnormal hemorheological properties in rats with DIC induced by Dextran 500.

  13. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Chang Yoon [The Hotchkiss School, Lakeville, CT (United States); Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ku, Cheol Ryong [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Cho, Yoon Hee, E-mail: wooriminji@gmail.com [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Eun Jig, E-mail: ejlee423@yuhs.ac [Endocrinology, Brain Korea 21 Project for Medical Science, Institute of Endocrine Research, and Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University College of Medicine, Seoul (Korea, Republic of); Endocrinology, Northwestern University Feinberg School of Medicine, Chicago, IL (United States)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. Black-Right-Pointing-Pointer PCA inhibits proliferation and migration in PDGF-induced VSMCs. Black-Right-Pointing-Pointer PCA has anti-platelet effects in ex vivo rat whole blood. Black-Right-Pointing-Pointer We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2 Prime -deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 {mu}M). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA's antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  14. Assessing intravascular volume by difference in pulse pressure in pigs submitted to graded hemorrhage.

    Science.gov (United States)

    Pestel, Gunther J; Hiltebrand, Luzius B; Fukui, Kimiko; Cohen, Delphine; Hager, Helmut; Kurz, Andrea M

    2006-10-01

    We assessed changes in intravascular volume monitored by difference in pulse pressure (dPP%) after stepwise hemorrhage in an experimental pig model. Six pigs (23-25 kg) were anesthetized (isoflurane 1.5 vol%) and mechanically ventilated to keep end-tidal CO2 (etCO2) at 35 mmHg. A PA-catheter and an arterial catheter were placed via femoral access. During and after surgery, animals received lactated Ringer's solution as long as they were considered volume responders (dPP>13%). Then animals were allowed to stabilize from the induction of anesthesia and insertion of catheters for 30 min. After stabilization, baseline measurements were taken. Five percent of blood volume was withdrawn, followed by another 5%, and then in 10%-increments until death from exsanguination occurred. After withdrawal of 5% of blood volume, all pigs were considered volume responders (dPP>13%); dPP rose significantly from 6.1+/-3.3% to 19.4+/-4.2%. The regression analysis of stepwise hemorrhage revealed a linear relation between blood loss (hemorrhage in %) and dPP (y=0.99*x+14; R2=0.7764; P<.0001). In addition, dPP was the only parameter that changed significantly between baseline and a blood loss of 5% (P<0.01), whereas cardiac output, stroke volume, heart rate, MAP, central venous pressure, pulmonary artery occlusion pressure, and systemic vascular resistance, respectively, remained unchanged. We conclude that in an experimental hypovolemic pig model, dPP correlates well with blood loss.

  15. An experimental study on the influence of the intravascular gianturco type stents on the vascular structures

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yeon Hyeon [Sejong General Hospital, Bucheon (Korea, Republic of); Park, Jae Hyung; Han, Joon Koo; Han, Man Chung; Kim, Chu Wan [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1991-07-15

    Twenty-seven Gianturco-type self-expandable stainless steel intravascular stents were placed into the infrarenal abdominal aortas (n=17) and inferior venae cavae (n=10) in 14 mongrel dogs. In 8 aortas, stents were delivered after balloon catheter-induced denudation of the intima, and in 4 out of the 8 aortas, the stents were also placed into the normal sites to compare the neointimal thickness of the normal and denuded sites. Angiography, light microscopic, and scanning electron microscopic examinations were performed after 1 week (n=1), 2 weeks (n=6), 3 weeks (n=5), and 6 weeks (n=2). The patency rate and thrombosis rate were 100% and 35% in the aortas and 100% and 60% in the inferior venae cavae. The aortic stent wires were covered with thin fibrinous membrane after 1 week. Nearly complete transparent neointimal covering was found in the aortas and caval veins after 2 weeks. There was no significant difference in intimal thickness between the denuded and normal aortas after 2 weeks ({rho} =0.51) and 3 weeks ({rho} =0.56). In 4 dogs with caval vein stents, there was evidence of hemorrhage infarction in the lungs. The thrombosis rate of 12 stents with a stent-artery ratio (SAR) of 1.5 or higher was 41%, while there was no thrombus on the 4 stents with SAR 1.2 or lower, except for 1 specimen after 1 week. It is suggested that stents with SAR 1.2 or lower are more suitable. The high thrombosis rate of the inferior venae cavae may be related with slow blood flow.

  16. Endothelial progenitor cell mobilization and increased intravascular nitric oxide in patients undergoing cardiac rehabilitation.

    Science.gov (United States)

    Paul, Jonathan D; Powell, Tiffany M; Thompson, Michael; Benjamin, Moshe; Rodrigo, Maria; Carlow, Andrea; Annavajjhala, Vidhya; Shiva, Sruti; Dejam, Andre; Gladwin, Mark T; McCoy, J Philip; Zalos, Gloria; Press, Beverly; Murphy, Mandy; Hill, Jonathan M; Csako, Gyorgy; Waclawiw, Myron A; Cannon, Richard O

    2007-01-01

    We investigated whether cardiac rehabilitation participation increases circulating endothelial progenitor cells (EPCs) and benefits vasculature in patients already on stable therapy previously shown to augment EPCs and improve endothelial function. Forty-six of 50 patients with coronary artery disease completed a 36-session cardiac rehabilitation program: 45 were treated with HMG-CoA reductase inhibitor (statin) therapy > or = 1 month (average baseline low-density lipoprotein cholesterol = 81 mg/dL). Mononuclear cells isolated from blood were quantified for EPCs by flow cytometry (CD133/VEGFR-2 cells) and assayed in culture for EPC colony-forming units (CFUs). In 23 patients, EPCs were stained for annexin-V as a marker of apoptosis, and nitrite was measured in blood as an indicator of intravascular nitric oxide. Endothelial progenitor cells increased from 35 +/- 5 to 63 +/- 10 cells/mL, and EPC-CFUs increased from 0.9 +/- 0.2 to 3.1 +/- 0.6 per well (both P < .01), but 11 patients had no increase in either measure. Those patients whose EPCs increased from baseline showed significant increases in nitrite and reduction in annexin-V staining (both P < .01) versus no change in patients without increase in EPCs. Over the course of the program, EPCs increased prior to increase in nitrite in the blood. Cardiac rehabilitation in patients receiving stable statin therapy and with low-density lipoprotein cholesterol at goal increases EPC number, EPC survival, and endothelial differentiation potential, associated with increased nitric oxide in the blood. Although this response was observed in most patients, a significant minority showed neither EPC mobilization nor increased nitric oxide in the blood.

  17. In-111-oxine labeled platelet scintigraphy for detection of intracardiac and intravascular thrombi

    Energy Technology Data Exchange (ETDEWEB)

    Hanano, Masaharu; Kimura, Michio; Ojima, Kenji [Niigata Univ. (Japan). School of Medicine

    1984-06-01

    /sup 111/In-labeled platelet scintigraphy was carried out in 20 patients suspected of thrombosis, to evaluate its efficacy for the detection of intracardiac and intravascular thrombi. Hemostatic studies including PT, aPTT, fibrinogen, FDP, platelet retention by Hellem II method, platelet aggregation induced by ADP (1 ..mu..M, 10 ..mu..M), collagen (2 ..mu..g/ml) and arachidonate (2 mM), and platelet survival were examined simultaneously. Two of these patients were also studied by fibrinogen scintigraphy labeled with sup(99m)Tc. The platelets obtained from the patients were labeled with /sup 111/In-oxine according to a method originated by Yui et al. In the platelet scintigram, positive findings were demonstrated in 9 cases : 2 left ventricular, 3 left atrial, and 4 vascular thrombi. These were in a good accordance to the findings obtained by at least one from angiography, echography and surgery. Platelet aggregation induced by 1 ..mu..M ADP was elevated in 4 of the 7 patients with positive findings and 3 of the 7 patients with negative findings. Shortened platelet survivals were observed in two of the 10 patients; dissecting aortic aneurysm and infective prosthetic valve endocarditis with hepatosplenomegaly. There was no significant difference in the platelet function and the platelet survival between the patients with positive and negative findings. It was difficult to detect thrombi by the fibrinogen scintigraphy labeled with sup(99m)Tc in the two patients studied. In conclusion, /sup 111/In-labeled platelet scintigraphy seems to be very useful to detect thrombi.

  18. Multidimensional segmentation of coronary intravascular ultrasound images using knowledge-based methods

    Science.gov (United States)

    Olszewski, Mark E.; Wahle, Andreas; Vigmostad, Sarah C.; Sonka, Milan

    2005-04-01

    In vivo studies of the relationships that exist among vascular geometry, plaque morphology, and hemodynamics have recently been made possible through the development of a system that accurately reconstructs coronary arteries imaged by x-ray angiography and intravascular ultrasound (IVUS) in three dimensions. Currently, the bottleneck of the system is the segmentation of the IVUS images. It is well known that IVUS images contain numerous artifacts from various sources. Previous attempts to create automated IVUS segmentation systems have suffered from either a cost function that does not include enough information, or from a non-optimal segmentation algorithm. The approach presented in this paper seeks to strengthen both of those weaknesses -- first by building a robust, knowledge-based cost function, and then by using a fully optimal, three-dimensional segmentation algorithm. The cost function contains three categories of information: a compendium of learned border patterns, information theoretic and statistical properties related to the imaging physics, and local image features. By combining these criteria in an optimal way, weaknesses associated with cost functions that only try to optimize a single criterion are minimized. This cost function is then used as the input to a fully optimal, three-dimensional, graph search-based segmentation algorithm. The resulting system has been validated against a set of manually traced IVUS image sets. Results did not show any bias, with a mean unsigned luminal border positioning error of 0.180 +/- 0.027 mm and an adventitial border positioning error of 0.200 +/- 0.069 mm.

  19. Improved automated lumen contour detection by novel multifrequency processing algorithm with current intravascular ultrasound system.

    Science.gov (United States)

    Kume, Teruyoshi; Kim, Byeong-Keuk; Waseda, Katsuhisa; Sathyanarayana, Shashidhar; Li, Wenguang; Teo, Tat-Jin; Yock, Paul G; Fitzgerald, Peter J; Honda, Yasuhiro

    2013-02-01

    The aim of this study was to evaluate a new fully automated lumen border tracing system based on a novel multifrequency processing algorithm. We developed the multifrequency processing method to enhance arterial lumen detection by exploiting the differential scattering characteristics of blood and arterial tissue. The implementation of the method can be integrated into current intravascular ultrasound (IVUS) hardware. This study was performed in vivo with conventional 40-MHz IVUS catheters (Atlantis SR Pro™, Boston Scientific Corp, Natick, MA) in 43 clinical patients with coronary artery disease. A total of 522 frames were randomly selected, and lumen areas were measured after automatically tracing lumen borders with the new tracing system and a commercially available tracing system (TraceAssist™) referred to as the "conventional tracing system." The data assessed by the two automated systems were compared with the results of manual tracings by experienced IVUS analysts. New automated lumen measurements showed better agreement with manual lumen area tracings compared with those of the conventional tracing system (correlation coefficient: 0.819 vs. 0.509). When compared against manual tracings, the new algorithm also demonstrated improved systematic error (mean difference: 0.13 vs. -1.02 mm(2) ) and random variability (standard deviation of difference: 2.21 vs. 4.02 mm(2) ) compared with the conventional tracing system. This preliminary study showed that the novel fully automated tracing system based on the multifrequency processing algorithm can provide more accurate lumen border detection than current automated tracing systems and thus, offer a more reliable quantitative evaluation of lumen geometry. Copyright © 2011 Wiley Periodicals, Inc.

  20. Determination of Stent Stenosis: An In Vivo Experimental Comparison of Intravascular Ultrasound and Angiography with Histology

    International Nuclear Information System (INIS)

    Schuermann, Karl; Vorwerk, Dierk; Uppenkamp, Robert; Klosterhalfen, Bernd; Buecker, Arno; Guenther, Rolf W.

    1998-01-01

    Purpose: To compare intravascular ultrasound (IVUS) and angiography with histology in determining the degree of stent stenosis in an in vivo experiment. Methods: In 16 sheep, a total of 64 stents were implanted into the external iliac arteries. Two stents were inserted on either side. Patency was followed by angiography and IVUS. Four types of stent were used: two Dacron-covered (Cragg Endopro and heparinized Cragg Endopro) and two non-covered (Cragg and Memotherm stents). Eight animals were killed after 1 month, eight others after 6 months. Histological sections were prepared from the stented vessels. Measurements of the patent and total stent diameters determined by IVUS, angiography, and histology were compared. Results: Correlation between IVUS and angiography was 0.75, between IVUS and histology 0.77, and between angiography and histology 0.85. A mean stent stenosis of 17 ± 11% (range 0-51%) was found on angiography, of 10 ± 11% (0-46%) on IVUS, and of 20 ± 11% (4%-49%) on histology. In comparison with histology, IVUS underestimated the degree of stenosis by 10 ± 8%, and angiography underestimated it by 3 ± 6%. Resolution of IVUS was calculated to be about 0.35 mm and that of angiography to be about 0.15 mm. Conclusion: Under experimental conditions, IVUS was not superior to angiography in determining the degree of stent stenosis in long-segment stenoses of iliac artery stents, when measurements were correlated with histology. Angiography is sufficient for following the patency of iliac artery stents

  1. High grade primary adrenal intravascular large B-cell lymphoma manifesting as Addison disease Linfoma intravascular de alto grado de células B grandes y origen suprarrenal que se manifiesta en forma de enfermedad de Addison

    OpenAIRE

    J. Venizelos; D. Tamiolakis; M. Lambropoulou; G. Alexiadis; G. Petrakis; N. Papadopoulos

    2007-01-01

    We report a rare case of a 68 aged male who presented with adrenal failure and was diagnosed of high grade large B-cell lymphoma primarily arising in the adrenal glands. The patient was administrated with additional chemotherapy but he passed away 7 months later due to infection in the lungs. Intravascular lymphoma should be suspected in patients with bilateral adrenal masses who present with rapidly progressive adrenal insufficiency.Publicamos el caso poco frecuente de un varón de 68 años de...

  2. Macromolecular contrast media. A new approach for characterising breast tumors with MR-mammography

    International Nuclear Information System (INIS)

    Daldrup, H.E.; Gossmann, A.; Koeln Univ.; Wendland, M.; Brasch, R.C.; Rosenau, W.

    1997-01-01

    The value of macromolecular contrast agents (MMCM) for the characterization of benign and malignant breast tumors will be demonstrated in this review. Animal studies suggest a high potential of MMCM to increase the specificity of MR-mammography. The concept of tumor differentiation is based on the pathological hyperpermeability of microvessels in malignant tumors. MMCM show a leak into the interstitium of carcinomas, whereas they are confined to the intravascular space in benign tumors. Capabilities and limitations of the MMCM-prototype. Albumin-Gd-DTPA, for breast tumor characterization will be summarized and compared to the standard low molecular weight contrast agent Gd-DTPA. Initial experience with new MMCM, such as Dendrimers, Gd-DTPA-Polylysine and MS-325 will be outlined. The potential of 'blood-pool'-iron oxides, such as AMI-227 for the evaluation of tumor microvascular permeabilities will be discussed. (orig.) [de

  3. Synthesis and evaluation of gadolinium complexes based on PAMAM as MRI contrast agents.

    Science.gov (United States)

    Yan, Guo-Ping; Hu, Bin; Liu, Mai-Li; Li, Li-Yun

    2005-03-01

    Diethylenetriaminepentaacetic acid (DTPA) and pyridoxamine (PM) were incorporated into the amine groups on the surface of ammonia-core poly(amidoamine) dendrimers (PAMAM, Generation 2.0-5.0) to obtain dendritic ligands. These dendritic ligands were reacted with gadolinium chloride to yield the corresponding dendritic gadolinium (Gd) complexes. The dendritic ligands and their gadolinium complexes were characterized by(1)HNMR, IR, UV and elemental analysis. Relaxivity studies showed that the dendritic gadolinium complexes possessed higher relaxation effectiveness compared with the clinically used Gd-DTPA. After administration of the dendritic gadolinium complexes (0.09 mmol kg(-1) ) to rats, magnetic resonance imaging of the liver indicated that the dendritic gadolinium complexes containing pyridoxamine groups enhanced the contrast of the MR images of the liver, provided prolonged intravascular duration and produced highly contrasted visualization of blood vessels.

  4. Aspiration of Barium Contrast

    Directory of Open Access Journals (Sweden)

    Cristina Fuentes Santos

    2014-01-01

    Full Text Available The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical file was reviewed, images were found of a barium swallow study that the patient had undergone months earlier, and we were able to observe the exact moment of the aspiration of the contrast material. The patient had been asymptomatic since the test.

  5. MR angiography of the carotid arteries and intracranial circulation: advantage of a high relaxivity contrast agent

    International Nuclear Information System (INIS)

    Anzalone, N.; Scotti, R.; Iadanza, A.

    2006-01-01

    Several studies have shown the usefulness of contrast-enhanced MR angiography (CE-MRA) for imaging the supraortic vessels, and, as a consequence, it has rapidly become a routine imaging modality. The main advantage over unenhanced techniques is the possibility to acquire larger volumes, allowing demonstration of the carotid artery from its origin to the intracranial portion. Most published studies on CE-MRA of the carotid arteries have been performed with standard Gd-based chelates whose T1 relaxivity values are similar. Recently new gadolinium chelates such as gadobenate dimeglumine (Gd-BOP-TA, MultiHance; Bracco Imaging, Milan, Italy) have been developed which have markedly higher intravascular T1 relaxivity values. When administered at an equivalent dose to that of a standard agent, these newer contrast agents produce significantly greater intravascular signal enhancement. The availability of an appropriate high-relaxivity contrast agent might also help to overcome some of the intrinsic technical problems (e. g. those related to flow) that affect time-of-flight (TOF) and phase contrast (PC) MR angiography of the intracranial vasculature. To avoid the problem of superimposition of veins, ultrafast gradient echo MRA techniques with very short TR and TE have been developed. Although the precise sequence parameters vary between manufacturers, they are basically similar. The choice between performing a time-resolved or high spatial resolution CE-MRA examination depends upon the precise clinical application. The most common applications include the study of cerebral aneurysms, arteriovenous malformations, dural arteriovenous fistulas and dural venous diseases

  6. Thyroid storm with multiple organ failure, disseminated intravascular coagulation, and stroke with a normal serum FT3 level.

    Science.gov (United States)

    Harada, Yuko; Akiyama, Hisanao; Yoshimoto, Tatsuji; Urao, Yasuko; Ryuzaki, Munekazu; Handa, Michiko

    2012-01-01

    Thyroid storm is a rare disorder with a sudden onset, rapid progression and high mortality. We experienced a case of thyroid storm which had a devastating course, including multiple organ failure (MOF), severe hypoglycemia, disseminated intravascular coagulation (DIC), and stroke. It was difficult to make a diagnosis of thyroid storm in the present patient, because she did not have a history of thyroid disease and her serum FT3 level was normal. Clinicians should be aware that thyroid storm can occur even when there is an almost normal level of thyroid hormones, and that intensive anticoagulation is required for patients with atrial fibrillation to prevent stroke after thyroid storm.

  7. The advantage of high relaxivity contrast agents in brain perfusion

    International Nuclear Information System (INIS)

    Cotton, F.; Hermier, M.

    2006-01-01

    Accurate MRI characterization of brain lesions is critical for planning therapeutic strategy, assessing prognosis and monitoring response to therapy. Conventional MRI with gadolinium-based contrast agents is useful for the evaluation of brain lesions, but this approach primarily depicts areas of disruption of the blood-brain barrier (BBB) rather than tissue perfusion. Advanced MR imaging techniques such as dynamic contrast agent-enhanced perfusion MRI provide physiological information that complements the anatomic data available from conventional MRI. We evaluated brain perfusion imaging with gadobenate dimeglumine (Gd-BOPTA, MultiHance; Bracco Imaging, Milan, Italy). The contrast-enhanced perfusion technique was performed on a Philips Intera 1.5-T MR system. The technique used to obtain perfusion images was dynamic susceptibility contrast-enhanced MRI, which is highly sensitive to T2* changes. Combined with PRESTO perfusion imaging, SENSE is applied to double the temporal resolution, thereby improving the signal intensity curve fit and, accordingly, the accuracy of the derived parametric images. MultiHance is the first gadolinium MR contrast agent with significantly higher T1 and T2 relaxivities than conventional MR contrast agents. The higher T1 relaxivity, and therefore better contrast-enhanced T1-weighted imaging, leads to significantly improved detection of BBB breakdown and hence improved brain tumor conspicuity and delineation. The higher T2 relaxivity allows high-quality T2*-weighted perfusion MRI and the derivation of good quality relative cerebral blood volume (rCBV) maps. We determined the value of MultiHance for enhanced T2*-weighted perfusion imaging of histologically proven (by surgery or stereotaxic biopsy) intraaxial brain tumors (n=80), multiple sclerosis lesions (n=10), abscesses (n=4), neurolupus (n=15) and stroke (n=16). All the procedures carried out were safe and no adverse events occurred. The acquired perfusion images were of good quality in

  8. Contrast media: future aspects

    International Nuclear Information System (INIS)

    Weinmann, H.J.; Platzek, J.; Schirmer, H.; Pietsch, H.; Carretero, J.; Harto, J.; Medina, J.; Riefke, B.; Martin, J.

    2005-01-01

    In spite of the dramatic development in CT, there was no major breakthrough in the iodinated contrast media development. New agents based on hybrid between MRI and CT compounds may be a new innovative alternative. This new approach may also open new indications such as radiotherapy. (orig.)

  9. Roentgen contrast medium

    International Nuclear Information System (INIS)

    Tamborski, C.

    1989-01-01

    The patent deals with a roentgen contrast medium containing a perfluorinebrominealkylether of the formula C m F 2m+1 OC n F 2n Br dispersed in water, preferentially in the presence of a non-ionic dispersing agent such as a fluorinated amidoaminoxide. 2 tabs

  10. High grade primary adrenal intravascular large B-cell lymphoma manifesting as Addison disease Linfoma intravascular de alto grado de células B grandes y origen suprarrenal que se manifiesta en forma de enfermedad de Addison

    Directory of Open Access Journals (Sweden)

    J. Venizelos

    2007-08-01

    Full Text Available We report a rare case of a 68 aged male who presented with adrenal failure and was diagnosed of high grade large B-cell lymphoma primarily arising in the adrenal glands. The patient was administrated with additional chemotherapy but he passed away 7 months later due to infection in the lungs. Intravascular lymphoma should be suspected in patients with bilateral adrenal masses who present with rapidly progressive adrenal insufficiency.Publicamos el caso poco frecuente de un varón de 68 años de edad que debutó con insuficiencia adrenal y fue diagnosticado de linfoma de alto grado de células B grandes ubicado principalmente en las glándulas suprarrenales. Al paciente le administraron quimioterapia adicional, pero falleció 7 meses después de infección pulmonar. El linfoma intravascular debe sospecharse en los pacientes con masas suprarrenales bilaterales que presenten insuficiencia adrenal rápidamente progresiva.

  11. Iodinated contrast media nephrotoxicity

    International Nuclear Information System (INIS)

    Meyrier, A.

    1994-01-01

    In the late seventies, iodinated contrast agents (ICA) were considered to be a major cause of acute iatrogenic renal failure. Over the last decade new contrast agents have been synthesized, nonionic and less hyperosmolar. The incidence of acute renal failure due to ICAs, varies from 3.7 to 70% of cases according to the series, with an average figure of 10.2%. The pathophysiology of ICA nephrotoxicity was mainly studied in laboratory animal models. Three main factors are involved in an inducing ICA-mediated decrease in glomerular filtration rate: reduction of the renal plasma flow, a direct cytotoxic effect on renal tubular cells and erythrocyte alteration leading to intra-renal sludge. Excluding dysglobulinemias with urinary excretion of immunoglobulin light chains, which represent a special case of maximum nephrotoxicity, 4 main risk factors of renal toxicity have been identified in nondiabetic subjects: previous renal failure with serum creatinine levels greater than 140 μmol per liter, extracellular dehydration, age over 60 and use of high doses of ICA and/or repeated ICA injections before serum creatinine levels return to baseline. Preventive measures for avoiding ICA nephrotoxicity are threefold: maintain or restore adequate hydration with saline infusion, stop NSAID treatment several days before ICA administration, and allow a 5 day interval before repeating contrast media injections. New, nonionic and moderately hyperosmolar contrast agents appear to be much less nephrotoxic than conventional ICAs in laboratory animals and in high-risk patients. It is advisable to select such contrast media for investigating high-risk patients. This approach was recently substantiated in well designed, randomized clinical studies which included more than 2 000 patients. (author)

  12. Evaluation of Directional Atherectomy Studied by Intravascular Ultrasound in Femoropopliteal Artery Stenosis

    International Nuclear Information System (INIS)

    Tielbeek, Alexander V.; Vroegindeweij, Dammis; Gussenhoven, Elma J.; Buth, Jacob; Landman, Guido H.M.

    1997-01-01

    Purpose: To evaluate the role of intravascular ultrasound (IVUS) before and after directional atherectomy (DA) in the treatment of femoropopliteal artery stenosis. Methods: In 12 patients with 16 stenoses IVUS was performed before and immediately after an angiographically successful DA. This was defined as a diameter reduction (DR) ≤ 50%, which was calculated using the minimal lumen diameter compared with the diameter of a nearby 'normal' segment. In the presence of residual plaque on IVUS an additional DA was performed. Endpoints studied were DR ≤ 30% on IVUS compared with the IVUS findings of the angiographically normal reference segment, or when no additional atherosclerotic material could be removed by further DA passages. Results: Additional DA (mean 1.6 per lesion) had to be performed in all patients. Initial DA increased the cross-sectional free lumen area (FLA) from 3.8 ± 2.0 mm 2 to 8.1 ± 2.7 mm 2 (p= 0.0004). Additional DA increased FLA to 9.3 ± 2.3 mm 2 (p= 0.002) after the second passage and to 9.8 ± 2.4 mm 2 (p= 0.09) after the final DA run. The plaque area (PLA) before DA decreased from 18.1 ± 4.2 mm 2 to 15.4 ± 4.8 mm 2 (p= 0.002) after the first passage, and to 13.5 ± 5.0 mm 2 (p= 0.004) and 12.8 ± 4.4 mm 2 (p= 0.07) after the second and final DA runs, respectively. PLA of the reference segment (9.5 ± 5.7 mm 2 ) was significantly smaller (p= 0.006) than the final PLA of the treated lesion, indicating a large amount of retained plaque. As a result of DA there was an increase in the area bordered by the medial layer, i.e., the total vessel area (from 21.9 ± 4.7 mm 2 to 23.0 ± 4.7 mm 2 ), significantly in eccentric and soft lesions. On IVUS, dissection and plaque rupture after the final passage was seen in 12 of 16 stenoses; two dissections were seen on the completion angiogram. After the final passage in all stenoses except three, the DR with IVUS was ≤ 30%. Conclusion: Lumen enlargement following DA is predominantly due to plaque

  13. Imaging findings of intravascular papillary endothelial hyperplasia presenting in extremities: correlation with pathological findings.

    Science.gov (United States)

    Lee, Sun Joo; Choo, Hye Jung; Park, Ji Sung; Park, Yeong-Mi; Eun, Choong Ki; Hong, Sung Hwan; Hwang, Ji Young; Lee, In Sook; Lee, Jongmin; Jung, Soo-Jin

    2010-08-01

    To describe magnetic resonance imaging (MRI) and ultrasound (US) findings of intravascular papillary endothelial hyperplasia (IPEH) arising in extremities. Six patients with IPEH confirmed by surgical resection were reviewed retrospectively. Before resection, 3 patients underwent both MRI and US and 3 patients underwent only MRI. Two radiologists retrospectively reviewed MR/US imaging results and correlated them with pathological features. The 6 IPEHs were diagnosed as 4 mixed forms and 2 pure forms. The pre-existing pathology of four mixed forms was intramuscular or intermuscular hemangioma. By MRI, the mixed form of IPEH (n = 4) revealed iso- to slightly high signal intensity containing nodule-like foci of high signal intensity on T1-weighted images (T1WI) and high signal intensity-containing nodule-like foci of low signal intensity on T2-weighted images (T2WI). The pure form of IPEH (n = 2) showed homogeneous iso- signal intensity on T1WI and high and low signal intensity containing nodule-like foci of low signal intensity on T2WI. On gadolinium-enhanced fat-suppressed T1WI, 50% of cases (n = 3: mixed forms) revealed peripheral, septal, and central enhancement. The other IPEHs (n = 3: 1 mixed and 2 pure forms) showed peripheral and septal enhancement or only peripheral enhancement. By US, two mixed forms of IPEH showed well-defined hypoechoic masses containing hyperechoic septa and central portion with vascularities. One pure form of IPEH was a homogeneous hypoechoic mass with septal and peripheral vascularities on color Doppler imaging. The foci of high signal intensity on T1WI, foci of low signal intensity on T2WI, and non-enhancing portions on MRI and the hypoechoic portion on US were histopathologically correlated with thrombi and the peripheral/septal or central enhancing areas on MRI, hyperechoic septa and the central portion on US, and septal/central or peripheral vascularities on color Doppler imaging corresponded to hypertrophic papillary epithelium and

  14. Imaging findings of intravascular papillary endothelial hyperplasia presenting in extremities: correlation with pathological findings

    International Nuclear Information System (INIS)

    Lee, Sun Joo; Choo, Hye Jung; Park, Ji Sung; Park, Yeong-Mi; Eun, Choong Ki; Hong, Sung Hwan; Hwang, Ji Young; Lee, In Sook; Lee, Jongmin; Jung, Soo-Jin

    2010-01-01

    To describe magnetic resonance imaging (MRI) and ultrasound (US) findings of intravascular papillary endothelial hyperplasia (IPEH) arising in extremities. Six patients with IPEH confirmed by surgical resection were reviewed retrospectively. Before resection, 3 patients underwent both MRI and US and 3 patients underwent only MRI. Two radiologists retrospectively reviewed MR/US imaging results and correlated them with pathological features. The 6 IPEHs were diagnosed as 4 mixed forms and 2 pure forms. The pre-existing pathology of four mixed forms was intramuscular or intermuscular hemangioma. By MRI, the mixed form of IPEH (n = 4) revealed iso- to slightly high signal intensity containing nodule-like foci of high signal intensity on T1-weighted images (T1WI) and high signal intensity-containing nodule-like foci of low signal intensity on T2-weighted images (T2WI). The pure form of IPEH (n = 2) showed homogeneous iso- signal intensity on T1WI and high and low signal intensity containing nodule-like foci of low signal intensity on T2WI. On gadolinium-enhanced fat-suppressed T1WI, 50% of cases (n = 3: mixed forms) revealed peripheral, septal, and central enhancement. The other IPEHs (n = 3: 1 mixed and 2 pure forms) showed peripheral and septal enhancement or only peripheral enhancement. By US, two mixed forms of IPEH showed well-defined hypoechoic masses containing hyperechoic septa and central portion with vascularities. One pure form of IPEH was a homogeneous hypoechoic mass with septal and peripheral vascularities on color Doppler imaging. The foci of high signal intensity on T1WI, foci of low signal intensity on T2WI, and non-enhancing portions on MRI and the hypoechoic portion on US were histopathologically correlated with thrombi and the peripheral/septal or central enhancing areas on MRI, hyperechoic septa and the central portion on US, and septal/central or peripheral vascularities on color Doppler imaging corresponded to hypertrophic papillary epithelium and

  15. Disseminated intravascular coagulopathy caused by Kikuchi–Fujimoto disease resulting in death: first case report in Turkey

    Directory of Open Access Journals (Sweden)

    Uslu E

    2014-02-01

    Full Text Available Emine Uslu,1 Sibel Gurbuz,2 Abdulsamet Erden,1 Fatma Aykas,1 Hatice Karagoz,1 Samet Karahan,1 Hatice Karaman,3 Ali Cetinkaya,1 Deniz Avci1 1Internal Medicine Department, 2Infection Disease Department, 3Clinical Pathology Department, Kayseri Training and Research Hospital, Kayseri, Turkey Abstract: Kikuchi disease, also called Kikuchi–Fujimoto disease or Kikuchi's histiocytic necrotizing lymphadenitis, is a rare, benign condition of unknown cause, usually characterized by cervical lymphadenopathy and fever. The diagnosis is based on histopathology. Our patient was a woman with bilateral cervical lymphadenopathy, fever, chest and abdominal pain, fatigue, maculopapular rash on her face, trunk, and upper and lower extremities. Immunological and rheumatological tests were negative. We took a cervical lymph node biopsy that showed a proliferative and necrotizing process centered in the paracortex characterized by patchy circumscribed or confluent areas of necrosis associated with karyorrhexis, and was remarkable by the absence of granulocytes and the paucity of plasma cells. These findings confirmed the diagnosis of Kikuchi's disease. The patient's hemoglobin values decreased, and the peripheral blood smear revealed schistocytes. Blood tests showed raised D-dimer, activated partial thromboplastin time, prothrombin time, and international normalized ratio with decreased fibrinogen. The patient's condition quickly worsened and disseminated intravascular coagulopathy eventually developed. Her initial management consisted of a corticosteroid and hydroxychloroquine. Keywords: disseminated intravascular coagulopathy, Kikuchi–Fujimoto disease, necrotizing lymphadenitis

  16. Pulmonary artery intravascular abscess: A rare complication of incomplete infective endocarditis treatment in the setting of injection drug use

    Directory of Open Access Journals (Sweden)

    Simran Gupta

    Full Text Available Infective endocarditis (IE is a serious complication of injection drug use. Right-sided IE encompasses 5–10% of all IE cases, with the majority involving the tricuspid valve (TV. The predominant causal organism is Staphylococcus aureus. Most cases of right-sided IE can be successfully treated with antimicrobials, but approximately 5–16% require eventual surgical intervention. We report the case of a 36-year-old female with active injection drug use who developed methicillin-sensitive Staphylococcus aureus IE of the tricuspid valve. Associated with poor adherence to medical therapy as a consequence of opioid addiction, she developed septic emboli to the lungs and an intravascular abscess in the left main pulmonary artery. These long-term potentially fatal, sequelae of incompletely treated IE require surgical intervention, as medical therapy is unlikely to be sufficient. Surgical management may involve TV replacement, pulmonary artery resection, and pneumonectomy. Prevention of these complications may have been achieved by concurrent opioid addiction therapy. An intravascular pulmonary artery abscess is a novel complication of advanced IE that has not been previously reported. This complication likely arose due to incomplete IE treatment as a consequence of opioid addiction, highlighting the need for concurrent addiction management. Intravenous antimicrobial therapy is likely not adequate, and surgical intervention, including pulmonary artery resection and pneumonectomy may be necessary. Keywords: Pulmonary artery abscess, Infective endocarditis, Injection drug use, Opioid use disorder

  17. Mamografia com contraste

    OpenAIRE

    Baptista, Rita; Silva, Carina; Reis, Cláudia

    2016-01-01

    O estudo pretendeu apresentar as indicações clínicas, vantagens e princípios da mamografia com contraste, identificar as evoluyções tecnológicas para a mamografia com contraste e caracterizar as práticas e os desafios dos técnicos de radiologia do Hospital de Santarém (único no país a utilizar esta técnica). O cancro da mama é uma das principais causas de morte nas mulheres, em todo o mundo, mas principalmente nos Estados Unidos da América, Canadá, Europa Ocidental e Austrália. Em Portugal, e...

  18. Current iodinated contrast media

    International Nuclear Information System (INIS)

    Stacul, F.

    2001-01-01

    The number of scientific papers on iodinated contrast media is declining. Indeed, comparative trials between high-osmolality and low-osmolality agents largely showed the higher safety and tolerability of the latter, and this is no longer a matter of discussion. Only financial constraints could prevent a total conversion to low-osmolality agents. Research comparing low-osmolality (nonionic monomers, ionic dimer) and iso-osmolality contrast media (nonionic dimers) are still ongoing. Both classes of nonionic compounds proved safer than the ionic dimer. The relative merits of nonionic monomers and nonionic dimers are a matter for debate, and criteria for a selective use of different agents for different procedures could be discussed. (orig.)

  19. Anisotropic contrast optical microscope.

    Science.gov (United States)

    Peev, D; Hofmann, T; Kananizadeh, N; Beeram, S; Rodriguez, E; Wimer, S; Rodenhausen, K B; Herzinger, C M; Kasputis, T; Pfaunmiller, E; Nguyen, A; Korlacki, R; Pannier, A; Li, Y; Schubert, E; Hage, D; Schubert, M

    2016-11-01

    An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm 2 object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves

  20. Patterns of contrast enhancement in the brain and meninges.

    Science.gov (United States)

    Smirniotopoulos, James G; Murphy, Frances M; Rushing, Elizabeth J; Rees, John H; Schroeder, Jason W

    2007-01-01

    Contrast material enhancement for cross-sectional imaging has been used since the mid 1970s for computed tomography and the mid 1980s for magnetic resonance imaging. Knowledge of the patterns and mechanisms of contrast enhancement facilitate radiologic differential diagnosis. Brain and spinal cord enhancement is related to both intravascular and extravascular contrast material. Extraaxial enhancing lesions include primary neoplasms (meningioma), granulomatous disease (sarcoid), and metastases (which often manifest as mass lesions). Linear pachymeningeal (dura-arachnoid) enhancement occurs after surgery and with spontaneous intracranial hypotension. Leptomeningeal (pia-arachnoid) enhancement is present in meningitis and meningoencephalitis. Superficial gyral enhancement is seen after reperfusion in cerebral ischemia, during the healing phase of cerebral infarction, and with encephalitis. Nodular subcortical lesions are typical for hematogenous dissemination and may be neoplastic (metastases) or infectious (septic emboli). Deeper lesions may form rings or affect the ventricular margins. Ring enhancement that is smooth and thin is typical of an organizing abscess, whereas thick irregular rings suggest a necrotic neoplasm. Some low-grade neoplasms are "fluid-secreting," and they may form heterogeneously enhancing lesions with an incomplete ring sign as well as the classic "cyst-with-nodule" morphology. Demyelinating lesions, including both classic multiple sclerosis and tumefactive demyelination, may also create an open ring or incomplete ring sign. Thick and irregular periventricular enhancement is typical for primary central nervous system lymphoma. Thin enhancement of the ventricular margin occurs with infectious ependymitis. Understanding the classic patterns of lesion enhancement--and the radiologic-pathologic mechanisms that produce them--can improve image assessment and differential diagnosis.

  1. Use of high concentration contrast media (HCCM): principles and rationale--body CT

    International Nuclear Information System (INIS)

    Brink, James A.

    2003-01-01

    Numerous complex pharmacokinetic interrelationships affect the use of contrast media for computed tomography (CT) imaging. The volume, concentration, and rate of injection, all affect the degree of enhancement that is achieved with an injection of contrast material. In addition, the injection technique, whether the contrast is infused with a constant injection rate (uniphasic injection) or whether the rate is altered during the injection (multiphasic injection) also affect the magnitude and duration of contrast enhancement. In body CT imaging, the liver poses unique challenges in managing the use of intravenous contrast material because of its dual blood supply and the need to complete imaging before equilibrium occurs between the intravascular and extravascular compartments. The magnitude of hepatic enhancement that is ultimately achieved is related primarily to the amount of iodinated contrast material that accumulates in the extravascular space within the target organ, independent of the speed of the CT scanner. The key determinant of the onset of the equilibrium phase is the injection duration. Given that a high injection flow rate (4-5 ml/s) is desirable for arterial phase imaging, the injection duration is maintained with use of an appropriate contrast volume. Thus, modifications of total iodine dose are best done with alterations in contrast concentration. The magnitude of arterial enhancement that is achieved is related to both the concentration and rate of contrast administration. The speed of the scanner determines its ability to record image data during the most advantageous time period, the peak of arterial enhancement. Thus, rapid imaging is particularly advantageous for optimal contrast use in CT angiography as well as in multiphasic imaging of the parenchymal organs

  2. Contrast Invariant SNR

    DEFF Research Database (Denmark)

    Weiss, Pierre; Escande, Paul; Dong, Yiqiu

    We design an image quality measure independent of local contrast changes, which constitute simple models of illumination changes. Given two images, the algorithm provides the image closest to the first one with the component tree of the second. This problem can be cast as a specific convex progra...... algorithms based on interior point methods. The algorithm has potential applications in change detection, color image processing or image fusion. A Matlab implementation is available at http://www.math.univ-toulouse.fr/_weiss/PageCodes.html....

  3. Local release of ATP into the arterial inflow and venous drainage of human skeletal muscle: insight from ATP determination with the intravascular microdialysis technique

    DEFF Research Database (Denmark)

    Mortensen, Stefan; Thaning, Pia; Nyberg, Michael Permin

    2011-01-01

    is released into plasma, we measured plasma [ATP] with the intravascular microdialysis technique at rest and during dynamic exercise (normoxia and hypoxia), passive exercise, thigh compressions and arterial ATP, tyramine and ACh infusion in a total of 16 healthy young men. Femoral arterial and venous...

  4. Impact of statin therapy on coronary plaque composition: A systematic review and meta-analysis of virtual histology intravascular ultrasound studies

    NARCIS (Netherlands)

    M. Banach (Maciej); C. Serban (Corina); A. Sahebkar (Amirhossein); D.P. Mikhailidis (Dimitri P.); S. Ursoniu (Sorin); K.K. Ray (Kausik K.); J. Rysz (Jacek); P.P. Toth (Peter); P. Muntner (Paul); S. Mosteoru (Svetlana); H.M. Garcia-Garcia (Hector); G.K. Hovingh (Kees); J.J.P. Kastelein (John); P.W.J.C. Serruys (Patrick)

    2015-01-01

    textabstractBackground: Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic

  5. Impact of statin therapy on coronary plaque composition: a systematic review and meta-analysis of virtual histology intravascular ultrasound studies

    NARCIS (Netherlands)

    Banach, Maciej; Serban, Corina; Sahebkar, Amirhossein; Mikhailidis, Dimitri P.; Ursoniu, Sorin; Ray, Kausik K.; Rysz, Jacek; Toth, Peter P.; Muntner, Paul; Mosteoru, Svetlana; García-García, Hector M.; Hovingh, G. Kees; Kastelein, John J. P.; Serruys, Patrick W.

    2015-01-01

    Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic review and meta-analysis

  6. Impact of analyzing fewer image frames per segment during offline volumetric radiofrequency based intravascular ultrasound measurements of target lesions prior to percutaneous coronary interventions

    NARCIS (Netherlands)

    Huisman, J.; Hartmann, M.; Hartmann, M.; Mintz, G.S.; van Houwelingen, G.K.; Stoel, M.G.; de Man, F.H.; Louwerenburg, H.; von Birgelen, Clemens

    2012-01-01

    In the present study, we evaluated the impact of a 50% reduction in number of image frames (every second frame) on the analysis time and variability of offline volumetric radiofrequency-based intravascular ultrasound (RF-IVUS) measurements in target lesions prior to percutaneous coronary

  7. Relation between lung perfusion defects and intravascular clots in acute pulmonary thromboembolism: assessment with breath-hold SPECT-CT pulmonary angiography fusion images.

    Science.gov (United States)

    Suga, Kazuyoshi; Yasuhiko, Kawakami; Iwanaga, Hideyuki; Tokuda, Osamu; Matsunaga, Naofumi

    2008-09-01

    The relation between lung perfusion defects and intravascular clots in acute pulmonary thromboembolism (PTE) was comprehensively assessed on deep-inspiratory breath-hold (DIBrH) perfusion SPECT-computed tomographic pulmonary angiography (CTPA) fusion images. Subjects were 34 acute PTE patients, who had successfully performed DIBrH perfusion SPECT using a dual-headed SPECT and a respiratory tracking system. Automated DIBrH SPECT-CTPA fusion images were used to assess the relation between lung perfusion defects and intravascular clots detected by CTPA. DIBrH SPECT visualized 175 lobar/segmental or subsegmental defects in 34 patients, and CTPA visualized 61 intravascular clots at variable locations in 30 (88%) patients, but no clots in four (12%) patients. In 30 patients with clots, the fusion images confirmed that 69 (41%) perfusion defects (20 segmental, 45 subsegmental and 4 lobar defects) of total 166 defects were located in lung territories without clots, although the remaining 97 (58%) defects were located in lung territories with clots. Perfusion defect was absent in lung territories with clots (one lobar branch and three segmental branches) in four (12%) of these patients. In four patients without clots, nine perfusion defects including four segmental ones were present. Because of unexpected dissociation between intravascular clots and lung perfusion defects, the present fusion images will be a useful adjunct to CTPA in the diagnosis of acute PTE.

  8. A new treatment planning formalism for catheter-based beta sources used in intravascular brachytherapy.

    Science.gov (United States)

    Patel, N S; Chiu-Tsao, S T; Tsao, H S; Harrison, L B

    2001-01-01

    Intravascular brachytherapy (IVBT) is an emerging modality for the treatment of atherosclerotic lesions in the artery. As part of the refinement in this rapidly evolving modality of treatment, the current simplistic dosimetry approach based on a fixed-point prescription must be challenged by future rigorous dosimetry method employing image-based three-dimensional (3D) treatment planning. The goals of 3D IVBT treatment planning calculations include (1) achieving high accuracy in a slim cylindrical region of interest, (2) accounting for the edge effect around the source ends, and (3) supporting multiple dwell positions. The formalism recommended by Task Group 60 (TG-60) of the American Association of Physicists in Medicine (AAPM) is applicable for gamma sources, as well as short beta sources with lengths less than twice the beta particle range. However, for the elongated beta sources and/or seed trains with lengths greater than twice the beta range, a new formalism is required to handle their distinctly different dose characteristics. Specifically, these characteristics consist of (a) flat isodose curves in the central region, (b) steep dose gradient at the source ends, and (c) exponential dose fall-off in the radial direction. In this paper, we present a novel formalism that evolved from TG-60 in maintaining the dose rate as a product of four key quantities. We propose to employ cylindrical coordinates (R, Z, phi), which are more natural and suitable to the slim cylindrical shape of the volume of interest, as opposed to the spherical coordinate system (r, theta, phi) used in the TG-60 formalism. The four quantities used in this formalism include (1) the distribution factor, H(R, Z), (2) the modulation function, M(R, Z), (3) the transverse dose function, h(R), and (4) the reference dose rate at 2 mm along the perpendicular bisector, D(R0=2 mm, Z0=0). The first three are counterparts of the geometry factor, the anisotropy function and the radial dose function in the

  9. Compensation of spectral artifacts in dual-modality intravascular optical coherence tomography and near-infrared spectroscopy (Conference Presentation)

    Science.gov (United States)

    Fard, Ali M.; Gardecki, Joseph A.; Ughi, Giovanni J.; Hyun, Chulho; Tearney, Guillermo J.

    2016-02-01

    Intravascular optical coherence tomography (OCT) is a high-resolution catheter-based imaging method that provides three-dimensional microscopic images of coronary artery in vivo, facilitating coronary artery disease treatment decisions based on detailed morphology. Near-infrared spectroscopy (NIRS) has proven to be a powerful tool for identification of lipid-rich plaques inside the coronary walls. We have recently demonstrated a dual-modality intravascular imaging technology that integrates OCT and NIRS into one imaging catheter using a two-fiber arrangement and a custom-made dual-channel fiber rotary junction. It therefore enables simultaneous acquisition of microstructural and composition information at 100 frames/second for improved diagnosis of coronary lesions. The dual-modality OCT-NIRS system employs a single wavelength-swept light source for both OCT and NIRS modalities. It subsequently uses a high-speed photoreceiver to detect the NIRS spectrum in the time domain. Although use of one light source greatly simplifies the system configuration, such light source exhibits pulse-to-pulse wavelength and intensity variation due to mechanical scanning of the wavelength. This can be in particular problematic for NIRS modality and sacrifices the reliability of the acquired spectra. In order to address this challenge, here we developed a robust data acquisition and processing method that compensates for the spectral variations of the wavelength-swept light source. The proposed method extracts the properties of the light source, i.e., variation period and amplitude from a reference spectrum and subsequently calibrates the NIRS datasets. We have applied this method on datasets obtained from cadaver human coronary arteries using a polygon-scanning (1230-1350nm) OCT system, operating at 100,000 sweeps per second. The results suggest that our algorithm accurately and robustly compensates the spectral variations and visualizes the dual-modality OCT-NIRS images. These

  10. Evolution of contrast agents for ultrasound imaging and ultrasound-mediated drug delivery

    Directory of Open Access Journals (Sweden)

    Vera ePaefgen

    2015-09-01

    Full Text Available Ultrasound is one of the most frequently used diagnostic methods. It is a non-invasive, comparably inexpensive imaging method with a broad spectrum of applications, which can be increased even more by using bubbles as contrast agents. There are various different types of bubbles: filled with different gases, composed of soft- or hard-shell materials, and ranging in size from nano- to micrometers. These intravascular contrast agents enable functional analyses, e.g. to acquire organ perfusion in real-time. Molecular analyses are achieved by coupling specific ligands to the bubbles’ shell, which bind to marker molecules in the area of interest. Bubbles can also be loaded with or attached to drugs, peptides or genes and can be destroyed by ultrasound pulses to locally release the entrapped agent. Recent studies show that ultrasound contrast agents are also valuable tools in hyperthermia-induced ablation therapy of tumors, or can increase cellular uptake of locally released drugs by enhancing membrane permeability. This review summarizes important steps in the development of ultrasound contrast agents and introduces the current clinical applications of contrast-enhanced ultrasound. Additionally, an overview of the recent developments in ultrasound probe design for functional and molecular diagnosis as well as for drug delivery is given.

  11. Changes in Renal Function in Elderly Patients Following Intravenous Iodinated Contrast Administration: A Retrospective Study

    International Nuclear Information System (INIS)

    Alsafi, A.; Alsafi, Z.; Lakhani, A.; Strickland, N.H.

    2014-01-01

    Contrast-induced nephropathy (CIN) is a recognised complication of intravascular administration of iodinated contrast media (ICM). Previous studies suggest a higher incidence in the elderly, but no large study has assessed this to date. We set out to assess changes in creatinine in elderly inpatients following computed tomography (CT) examination and compare those who received intravenous contrast to those who did not. Methods. Using the Radiology Information System in two teaching hospitals, inpatients over the age of seventy who had a CT examination and a baseline creatinine were identified and their follow-up creatinine levels were analysed. Elderly inpatients who underwent a non contrast CT over the same period were used as controls. Results. 677 elderly inpatients who received ICM were compared with 487 controls. 9.2% of patients who received ICM developed acute kidney injury (AKI) compared to 3.5% of inpatient controls (Ρ<0.0001). Patients with higher baseline eGFR had a higher incidence of post-CT AKI. Conclusions. The incidence of post-CT AKI is higher in patients who received IV ICM compared to those who did not; the difference may be partly attributable to contrast-induced nephropathy. This suggests that the incidence of CIN in the elderly may not be as high as previously thought.

  12. Phase Contrast Imaging

    DEFF Research Database (Denmark)

    1996-01-01

    The invention relates to a method and a system for synthesizing a prescribed intensity pattern based on phase contrast imaging that is not based on the assumption of prior art methods that the pahase shift phi is less than 1 radian. An improved method based on a simple imaging operation...... phasors attain predetermined values for predetermined spatial frequencies, and the phasor value of the specific resolution element of the spatial phase mask corresponds to a distinct intensity level of the image of the resolution element in the intensity pattern, and a spatial phase filter for phase...... shifting of a part of the electromagntic radiation, in combination with an imaging system for generation of the intensity pattern by interference in the image plane of the imaging system between the part of the electromagnetic raidation that has been phase shifted by the phase filter and the remaining part...

  13. Paramagnetic contrast material

    International Nuclear Information System (INIS)

    McNamara, M.T.

    1987-01-01

    Paramagnetic contrast materials have certainly demonstrated clinical utility in a variety of organ systems for improved detection of various neoplastic, inflammatory, infectious, and physiologic abnormalities. Although the more commonly employed extracellular agents, such as Gd-DTPA, have been quite safe and useful, particularly in the CNS, it is almost certain that other substances will achieve more success in various other organs, such as iron oxides in the reticuloendothelial system and persisting extracellular agents in the cardiovascular system. Finally, as MRI technology continues to evolve, producing such exciting new sequences as gradient-echo fast scans, the roles of currently existing and newly discovered paramagnetic pharmaceuticals must be continuously reevaluated both to obtain maximum clinical benefit and to guide the search for newer agents that may further optimize the diagnostic efficacy of MRI

  14. New MR contrast agent

    International Nuclear Information System (INIS)

    Grossman, C.D.; Subramanian, G.; Schneider, R.; Szeverenyi, N.E.; Rosenbaum, A.M.; Gagne, G.; Tillapaugh-Fay, G.; Berlin, R.; Ritter-Hrncirik, C.; Yu, S.

    1990-01-01

    This paper evaluates an MR contrast agent-meglumine tris-(2,6-dicarboxypyridine) gadolinium (III) or gadolinium dipicolinate (Gd-DPC)-produced in-house. Rats were anesthetized with pentobarbital. For renal imaging, bowel motion artifact was minimized with glucagon (0.014 mg/kg, intravenous (IV)). Enhanced images were generated on a 2-T chemical shift imaging system with a 31-cm horizontal bore magnet after IV injection of Gd-DPC (100 μM/kg). Coronal sections of the kidneys and sagittal sections of the brain, 2 mm thick, were made. Six to eight excitations and 128 or 356 phase-encoding steps were used for each image. Control animals were injected with equivalent doses of gadopentetate dimeglumine

  15. Successful Control of Disseminated Intravascular Coagulation by Recombinant Thrombomodulin during Arsenic Trioxide Treatment in Relapsed Patient with Acute Promyelocytic Leukemia

    Directory of Open Access Journals (Sweden)

    Motohiro Shindo

    2012-01-01

    Full Text Available Disseminated intravascular coagulation (DIC frequently occurs in patients with acute promyelocytic leukemia (APL. With the induction of therapy in APL using all-trans retinoic acid (ATRA, DIC can be controlled in most cases as ATRA usually shows immediate improvement of the APL. However, arsenic trioxide (ATO which has been used for the treatment of relapse in APL patients has shown to take time to suppress APL cells, therefore the control of DIC in APL with ATO treatment is a major problem. Recently, the recombinant soluble thrombomodulin fragment has received a lot of attention as the novel drug for the treatment of DIC with high efficacy. Here, we present a relapsed patient with APL in whom DIC was successfully and safely controlled by rTM during treatment with ATO.

  16. Intravascular ultrasound guided directional atherectomy versus directional atherectomy guided by angiography for the treatment of femoropopliteal in-stent restenosis

    Science.gov (United States)

    Krishnan, Prakash; Tarricone, Arthur; K-Raman, Purushothaman; Majeed, Farhan; Kapur, Vishal; Gujja, Karthik; Wiley, Jose; Vasquez, Miguel; Lascano, Rheoneil A.; Quiles, Katherine G.; Distin, Tashanne; Fontenelle, Ran; Atallah-Lajam, Farah; Kini, Annapoorna; Sharma, Samin

    2017-01-01

    Background: The aim of this study was to compare 1-year outcomes for patients with femoropopliteal in-stent restenosis using directional atherectomy guided by intravascular ultrasound (IVUS) versus directional atherectomy guided by angiography. Methods and results: This was a retrospective analysis for patients with femoropopliteal in-stent restenosis treated with IVUS-guided directional atherectomy versus directional atherectomy guided by angiography from a single center between March 2012 and February 2016. Clinically driven target lesion revascularization was the primary endpoint and was evaluated through medical chart review as well as phone call follow up. Conclusions: Directional atherectomy guided by IVUS reduces clinically driven target lesion revascularization for patients with femoropopliteal in-stent restenosis. PMID:29265002

  17. Factors influencing nurses' decision-making process on leaving in the peripheral intravascular catheter after 96 hours: a longitudinal study.

    Science.gov (United States)

    Palese, Alvisa; Cassone, Andrea; Kulla, Annamaria; Dorigo, Sabrina; Magee, Jesse; Artico, Marco; Camero, Francesco; Cassin, Catia; Cialdella, Sandra; Floridia, Giuseppe; Nadlišek, Boris; Palcic, Annamaria; Valle, Giulia; Sclauzero, Paola

    2011-01-01

    The clinical and research debate on the peripheral intravascular (PIV) catheter length of stay in situ is ongoing. The principal aim of this study was to explore the factors behind a nurse's decision to leave a PIV in place for more than 96 hours. The study focused on 7 northern Italian hospitals in 2009. A consequent sample of 269 PIV catheters was included. Direct observation and interviews were adopted. The time of the expected PIV replacement was fixed at 96 hours after its positioning, in accordance with the international guideline. Several factors were taken into account in regard to replacement of the PIV catheters by nurses, ranging from analysis based on their own clinical experience with PIV complications and analysis of the patient's clinical situation to the critical analysis of their own work situation. This clinical decision-making process is valuable: leaving the PIV in place for more than 96 hours is a complex decision and not simply a guideline violation.

  18. Linear-regression convolutional neural network for fully automated coronary lumen segmentation in intravascular optical coherence tomography

    Science.gov (United States)

    Yong, Yan Ling; Tan, Li Kuo; McLaughlin, Robert A.; Chee, Kok Han; Liew, Yih Miin

    2017-12-01

    Intravascular optical coherence tomography (OCT) is an optical imaging modality commonly used in the assessment of coronary artery diseases during percutaneous coronary intervention. Manual segmentation to assess luminal stenosis from OCT pullback scans is challenging and time consuming. We propose a linear-regression convolutional neural network to automatically perform vessel lumen segmentation, parameterized in terms of radial distances from the catheter centroid in polar space. Benchmarked against gold-standard manual segmentation, our proposed algorithm achieves average locational accuracy of the vessel wall of 22 microns, and 0.985 and 0.970 in Dice coefficient and Jaccard similarity index, respectively. The average absolute error of luminal area estimation is 1.38%. The processing rate is 40.6 ms per image, suggesting the potential to be incorporated into a clinical workflow and to provide quantitative assessment of vessel lumen in an intraoperative time frame.

  19. Acute Kidney Injury due to Menstruation-related Disseminated Intravascular Coagulation in an Adenomyosis Patient: A Case Report

    Science.gov (United States)

    Son, Jungmin; Seong, Eun Young; Song, Sang Heon; Lee, Soo Bong; Kang, Jin; Yang, Byeong Yun; Lee, Su Jin; Choi, Jong-Ryeol; Lee, Kyu-Sup; Kwak, Ihm Soo

    2010-01-01

    The authors report a case of acute kidney injury (AKI) resulting from menstruation-related disseminated intravascular coagulation (DIC) in an adenomyosis patient. A 40-yr-old woman who had received gonadotropin for ovulation induction therapy presented with anuria and an elevated serum creatinine level. Her medical history showed primary infertility with diffuse adenomyosis. On admission, her pregnancy test was negative and her menstrual cycle had started 1 day previously. Laboratory data were consistent with DIC, and it was believed to be related to myometrial injury resulting from heavy intramyometrial menstrual flow. Gonadotropin is considered to play an important role in the development of fulminant DIC. This rare case suggests that physicians should be aware that gonadotropin may provoke fulminant DIC in women with adenomyosis. PMID:20808684

  20. Linear-regression convolutional neural network for fully automated coronary lumen segmentation in intravascular optical coherence tomography.

    Science.gov (United States)

    Yong, Yan Ling; Tan, Li Kuo; McLaughlin, Robert A; Chee, Kok Han; Liew, Yih Miin

    2017-12-01

    Intravascular optical coherence tomography (OCT) is an optical imaging modality commonly used in the assessment of coronary artery diseases during percutaneous coronary intervention. Manual segmentation to assess luminal stenosis from OCT pullback scans is challenging and time consuming. We propose a linear-regression convolutional neural network to automatically perform vessel lumen segmentation, parameterized in terms of radial distances from the catheter centroid in polar space. Benchmarked against gold-standard manual segmentation, our proposed algorithm achieves average locational accuracy of the vessel wall of 22 microns, and 0.985 and 0.970 in Dice coefficient and Jaccard similarity index, respectively. The average absolute error of luminal area estimation is 1.38%. The processing rate is 40.6 ms per image, suggesting the potential to be incorporated into a clinical workflow and to provide quantitative assessment of vessel lumen in an intraoperative time frame. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  1. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    DEFF Research Database (Denmark)

    Huisman, Jennifer; Egede, Rasmus; Rdzanek, Adam

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility...... of volumetric VH-IVUS measurements, experienced analysts of 4 European IVUS centers performed independent analyses (in total 8,052 cross-sectional analyses) to obtain volumetric data of 40 coronary segments (length 20.0 ± 0.3 mm) from target lesions prior to percutaneous intervention that were performed...... in the setting of stable (65%) or unstable angina pectoris (35%). Geometric and compositional VH-IVUS measurements were highly correlated for the different comparisons. Overall intraclass correlation for vessel, lumen, plaque volume and plaque burden was 0.99, 0.92, 0.96, and 0.83, respectively; for fibrous...

  2. Bioresorbable Scaffold for Treatment of Coronary Artery Lesions: Intravascular Ultrasound Results From the ABSORB Japan Trial.

    Science.gov (United States)

    Okada, Kozo; Honda, Yasuhiro; Kitahara, Hideki; Otagiri, Kyuhachi; Tanaka, Shigemitsu; Hollak, M Brooke; Yock, Paul G; Popma, Jeffrey J; Kusano, Hajime; Cheong, Wai-Fung; Sudhir, Krishnankutty; Fitzgerald, Peter J; Kimura, Takeshi

    2018-04-09

    The aim of this study was to characterize post-procedural intravascular ultrasound (IVUS) findings in the ABSORB Japan trial, specifically stratified by the size of target coronary arteries. Despite overall noninferiority confirmed in recent randomized trials comparing bioresorbable vascular scaffolds (BVS) (Absorb BVS) and cobalt-chromium everolimus-eluting metallic stents (CoCr-EES), higher event rates of Absorb BVS have been reported with suboptimal deployment, especially in small coronary arteries. In the ABSORB Japan trial, 150 patients (2:1 randomization) were scheduled in the IVUS cohort. Small vessel was defined as mean reference lumen diameter strategy, possibly different between polymeric and metallic devices, needs to be established for bioresorbable scaffold technology. (AVJ-301 Clinical Trial: A Clinical Evaluation of AVJ-301 Absorb™ BVS) in Japanese Population [ABSORB JAPAN]; NCT01844284). Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  3. Comparison of intravascular ultrasound and angiographic assessement of coronary reference segment size in patients with type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Mintz, Gary S

    2008-01-01

    During percutaneous coronary intervention, the reference segment is assessed angiographically. This report described the discrepancy between angiographic and intravascular ultrasound (IVUS) assessment of reference segment size in patients with type 2 diabetes mellitus. Preintervention IVUS was used...... to study 62 de novo lesions in 41 patients with type 2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal-looking segments within 5 mm proximal and distal to the lesion. Plaque burden...... was measured as plaque CSA/external elastic membrane (EEM) CSA. Using IVUS, the reference lumen diameter was 2.80 +/- 0.42 mm and the reference EEM diameter was 4.17 +/- 0.56 mm. The angiographic reference diameter was 2.63 +/- 0.36 mm. Mean difference between the IVUS EEM diameter and angiographic reference...

  4. Optical Coherence Tomography Analysis of Attenuated Plaques Detected by Intravascular Ultrasound in Patients with Acute Coronary Syndromes

    Directory of Open Access Journals (Sweden)

    Takashi Kubo

    2011-01-01

    Full Text Available Background. Recent intravascular ultrasound (IVUS studies have demonstrated that hypoechoic plaque with deep ultrasound attenuation despite absence of bright calcium is common in acute coronary syndrome. Such “attenuated plaque” may be an IVUS characteristic of unstable lesion. Methods. We used optical coherence tomography (OCT in 104 patients with unstable angina to compare lesion characteristics between IVUS-detected attenuated plaque and nonattenuated plaque. Results. IVUS-detected attenuated plaque was observed in 41 (39% patients. OCT-detected lipidic plaque (88% versus 49%, <0.001, thin-cap fibroatheroma (48% versus 16%, <0.001, plaque rupture (44% versus 11%, <0.001, and intracoronary thrombus (54% versus 17%, <0.001 were more often seen in IVUS-detected attenuated plaques compared with nonattenuated plaques. Conclusions. IVUS-detected attenuated plaque has many characteristics of unstable coronary lesion. The presence of attended plaque might be an important marker of lesion instability.

  5. Determination of regional flow by use of intravascular PET tracers: microvascular theory and experimental validation for pig livers

    DEFF Research Database (Denmark)

    Munk, O L; Bass, L; Feng, H

    2003-01-01

    Today, the standard approach for the kinetic analysis of dynamic PET studies is compartment models, in which the tracer and its metabolites are confined to a few well-mixed compartments. We examine whether the standard model is suitable for modern PET data or whether theories including more...... physiologic realism can advance the interpretation of dynamic PET data. A more detailed microvascular theory is developed for intravascular tracers in single-capillary and multiple-capillary systems. The microvascular models, which account for concentration gradients in capillaries, are validated and compared...... with the standard model in a pig liver study. METHODS: Eight pigs underwent a 5-min dynamic PET study after (15)O-carbon monoxide inhalation. Throughout each experiment, hepatic arterial blood and portal venous blood were sampled, and flow was measured with transit-time flow meters. The hepatic dual...

  6. Intravascular ultrasound as a novel tool for the diagnosis and targeted treatment of functional popliteal artery entrapment syndrome

    Directory of Open Access Journals (Sweden)

    Anna E. Boniakowski, MD

    2017-06-01

    Full Text Available Functional popliteal artery entrapment syndrome can be difficult to diagnose, as the imaging modalities presently employed are designed to detect anatomic entrapment. We describe a novel imaging technique to aid in diagnosis in this cohort. A 22-year-old cyclist presented with exercise-limiting claudication. Magnetic resonance angiography with provocative maneuvers was nondiagnostic. Digital subtraction angiography revealed long-segment occlusion of the popliteal artery with plantar flexion; however, the specific site of compression remained unclear. Intravascular ultrasound allowed specific localization of compression and further confirmed the diagnosis. Thus, we report this as an adjunctive imaging modality to definitively diagnose functional popliteal artery entrapment syndrome and to assist in operative planning.

  7. Lack of plasma albumin impairs intravascular lipolysis and explains the associated free fatty acids deficiency and hypertriglyceridemia

    Directory of Open Access Journals (Sweden)

    Oliveira Helena CF

    2010-12-01

    Full Text Available Abstract Background Abnormalities in lipid metabolism and transport are hallmarks in analbuminemic Nagase rats (NAR and humans. Triglyceridemia is nearly 3- to 5-fold higher in female NAR than in control Sprague-Dawley rats (SDR. Also, NAR present with a severe plasma free fatty acid (FFA deficit. There are conflicting results regarding the mechanisms underlying NAR hypertriglyceridemia. Objective We aimed at investigating whether liver lipogenesis and triglyceride secretion rates into the plasma contribute to the hypertriglyceridemia in NAR. We also studied whether heparin or albumin administration would release the hypothesized lipolysis inhibition in NAR. Methods The incorporation of tritiated water into lipids and the linear accumulation rate of plasma triglycerides after Triton WR1339 injection were the measures of liver lipogenesis and triglyceride secretion rates. Results Lipogenesis (596 ± 40 vs. 929 ± 124 μmol 3H2O/g/h and triglyceride (4.25 ± 1.00 vs. 7.04 ± 1.68 mg/dL/min secretion rates were slower (P ≤ 0.05 in fasted NAR than in control SDR. The injection of either heparin or albumin elicited an increase in NAR plasma FFA levels over time. FFA levels reached control levels 90 min after the albumin administration, increasing from 0.36 ± 0.05 to 1.34 ± 0.16 mEq/L (P ≤ 0.05. These results indicate that the lack of plasma albumin inhibits intravascular lipolysis and causes the FFA deficit observed in NAR. Conclusion NAR hepatic triglyceride synthesis and output do not contribute to NAR hypertriglyceridemia. We propose that the lack of albumin diminishes intravascular lipolysis which reduces the plasma triglyceride removal rate and explain both NAR hypertriglyceridemia and FFA deficiency.

  8. Erythrocyte creatine as a marker of intravascular hemolysis due to left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Kubo, Toru; Okumiya, Toshika; Baba, Yuichi; Hirota, Takayoshi; Tanioka, Katsutoshi; Yamasaki, Naohito; Sugiura, Tetsuro; Doi, Yoshinori L; Kitaoka, Hiroaki

    2016-03-01

    Erythrocyte creatine, a marker of erythrocyte age that increases with shortening of erythrocyte survival, has been reported to be a quantitative and reliable marker for intravascular hemolysis. We hypothesized that hemolysis could also occur due to intraventricular obstruction in patients with hypertrophic cardiomyopathy (HCM). The purpose of this study was to examine the presence of subclinical hemolysis and the relation between intravascular hemolysis and intraventricular pressure gradient (IVPG). We measured erythrocyte creatine in 92 HCM patients. Twelve patients had left ventricular outflow tract obstruction (LVOTO), 4 had midventricular obstruction (MVO), and the remaining 76 were non-obstructive. Erythrocyte creatine levels ranged from 0.92 to 4.36μmol/g hemoglobin. Higher levels of erythrocyte creatine were associated with higher IVPG (r=0.437, pcreatine levels are high (≥1.8μmol/g hemoglobin), subclinical hemolysis is considered to be present. Half of LVOTO patients and no MVO patients showed high erythrocyte creatine levels. Although non-obstructive patients did not show significant intraventricular obstruction at rest, some showed high erythrocyte creatine levels. When LVOT-PG was measured during the strain phase of the Valsalva maneuver in 20 non-obstructive patients, 7 of those 20 patients showed LVOTO. In the 20 patients, there was no relation between erythrocyte creatine levels and LVOT-PG before the Valsalva maneuver (r=0.125, p=0.600), whereas there was a significant correlation between erythrocyte creatine and LVOT-PG provoked by the Valsalva maneuver (r=0.695, p=0.001). There is biochemical evidence of subclinical hemolysis in patients with HCM, and this hemolysis seems to be associated with LVOTO provoked by daily physical activities. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  9. Induction Therapy With Antithymocyte Globulin in Patients Undergoing Cardiac Transplantation Is Associated With Decreased Coronary Plaque Progression as Assessed by Intravascular Ultrasound.

    Science.gov (United States)

    Azarbal, Babak; Cheng, Richard; Vanichsarn, Christopher; Patel, Jignesh K; Czer, Lawrence S; Chang, David H; Kittleson, Michelle M; Kobashigawa, Jon A

    2016-01-01

    Antithymocyte globulin (ATG) is used as induction therapy after cardiac transplant for enhancing immunosuppression and delaying the initiation of nephrotoxic drugs. It is unknown if ATG induction is associated with decreased coronary plaque progression by intravascular ultrasound (IVUS). Patients transplanted between March 2010 and December 2012 with baseline and 1-year IVUS were included. All patients transplanted were included in a secondary analysis. Change in plaque progression was measured in a blinded fashion on matched coronary segments and contrasted between patients induced with ATG and those who were not. One hundred and three patients were included in IVUS arms. Mean age at transplant was 55.8 ± 12.6 years, and 33.0% were female. Patients induced with ATG were more sensitized (54.3% versus 14.3%). Plaque progression was attenuated in patients who received ATG by changes in maximal intimal area (1.0 ± 1.2 versus 2.3 ± 2.6 mm(2); P = 0.001), maximal percent stenosis (6.3 ± 7.9 versus 12.8 ± 12.3%; = 0.003), maximal intimal thickness (0.2 ± 0.2 versus 0.3 ± 0.3 mm; P = 0.035), and plaque volume (0.5 ± 0.7 versus 1.0 ± 1.3 mm(3)/mm; P = 0.016). Rapid plaque progression by maximal percent stenosis (≥ 20%) occurred less frequently in the ATG arm (4.3% versus 26.3; P = 0.003). Survival (P = 0.242) and any treated rejection (P = 0.166) were not statistically different between groups. Patients receiving ATG had a higher rate of first-year infection (P = 0.003), perhaps related to increased intravenous antibiotic use immediately postoperatively, and a trend toward more biopsy-proven rejection (P = 0.073). Induction therapy with ATG is associated with reduced first-year coronary plaque progression as assessed by IVUS, despite an increased prevalence of sensitized patients with a trend toward more rejection. © 2016 American Heart Association, Inc.

  10. Informed consent in contrast-enhanced CT. Understanding of risks and identification of possible prognostic factors

    International Nuclear Information System (INIS)

    Roehrl, S.; Dendl, L.M.; Scharf, G.; Stroszczynski, C.; Schreyer, A.G.; Zeman, F.

    2015-01-01

    Aim of our study was to assess understanding of risks associated with intravascular application of contrast media in patients undergoing CT examination. We wanted to evaluate epidemiologic and socio-economic prognostic factors for a higher understanding of risks. Additionally, we evaluated a possible correlation between an extensive, outcome-oriented oral informed consent and better understanding of risks. 120 patients distributed in 2 study arms participated in this prospective study. In study arm I, the treating physician was not informed that his patients participated in a study whereas the physician in study arm II knew about the survey. After the informed consent we performed a standardized, semi-structured interview to enquire the 3 most frequent risks of intravascular application of contrast agents (anaphylactoid reactions, nephropathy and thyrotoxic crisis) and epidemiologic data. The understanding of the risks was evaluated using a 6 point scale. Patients scored 3.73 points in study arm I and 4.93 points in arm II on average. The statistical difference between both study arms was highly significant (p < 0.001). In a combined logistic regression analysis, only ''higher education'' (p = 0.001) and participation in study arm II (p =0.001) showed a significant connection to a better understanding of risks. Patients profit from an outcome-oriented and individualized informed consent. Due to the significant correlation between educational level and understanding of risks, informed consent should be adjusted to the educational status of the individual patient, e.g. by using didactic aids or individualized information sheets.

  11. Contrast-enhanced ultrasound in the diagnosis of nodules in liver cirrhosis.

    Science.gov (United States)

    Kim, Tae Kyoung; Jang, Hyun-Jung

    2014-04-07

    Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents are useful for the diagnosis of the nodules in liver cirrhosis. CEUS can be used as a problem-solving method for indeterminate nodules on computed tomography (CT) or magnetic resonance imaging (MRI) or as an initial diagnostic test for small newly detected liver nodules. CEUS has unique advantages over CT and MRI including no renal excretion of contrast, real-time imaging capability, and purely intravascular contrast. Hepatocellular carcinoma (HCC) is characterized by arterial-phase hypervascularity and later washout (negative enhancement). Benign nodules such as regenerative nodules or dysplastic nodules are usually isoechoic or slightly hypoechoic in the arterial phase and isoechoic in the late phase. However, there are occasional HCC lesions with atypical enhancement including hypovascular HCC and hypervascular HCC without washout. Cholangiocarcinomas are infrequently detected during HCC surveillance and mostly show rim-like or diffuse hypervascularity followed by rapid washout. Hemangiomas are often found at HCC surveillance and are easily diagnosed by CEUS. CEUS can be effectively used in the diagnostic work-up of small nodules detected at HCC surveillance. CEUS is also useful to differentiate malignant and benign venous thrombosis and to guide and monitor the local ablation therapy for HCC.

  12. In which patients should serum creatinine be measured before iodinated contrast medium administration?

    International Nuclear Information System (INIS)

    Thomsen, Henrik S.

    2005-01-01

    Routine measurement of serum creatinine before injection of intravascular iodinated contrast material in all patients would be cumbersome and have an associated cost. There is doubt about whether serum creatinine should be measured routinely in all patients or selectively. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines on this important practical issue. A literature search was carried out and summarized in a report. Based on the available information and discussions amongst the members of the Committee, guidelines were produced. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. The practice for identifying patients at risk of contrast medium induced nephropathy varies considerably from one institution to another. Patients at risk constitute only a small percentage of all cases referred for contrast enhanced imaging examination. However, it is important to identify them and take the necessary precautions. Recent serum creatinine level should be available in patients with an increased probability of a raised serum creatinine level (renal disease, renal surgery, proteinuria, diabetes mellitus, hypertension, gout, current intake of nephrotoxic drugs). A simple guideline has been produced. (orig.)

  13. In which patients should serum creatinine be measured before iodinated contrast medium administration?

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, Henrik S. [Copenhagen University Hospital, Herlev (Denmark). Department of Diagnostic Radiology; Morcos, Sameh K. [Northern General Hospital, Department of Diagnostic Imaging, Sheffield Teaching Hospitals NHS Trust, Sheffield (United Kingdom)

    2005-04-01

    Routine measurement of serum creatinine before injection of intravascular iodinated contrast material in all patients would be cumbersome and have an associated cost. There is doubt about whether serum creatinine should be measured routinely in all patients or selectively. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines on this important practical issue. A literature search was carried out and summarized in a report. Based on the available information and discussions amongst the members of the Committee, guidelines were produced. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. The practice for identifying patients at risk of contrast medium induced nephropathy varies considerably from one institution to another. Patients at risk constitute only a small percentage of all cases referred for contrast enhanced imaging examination. However, it is important to identify them and take the necessary precautions. Recent serum creatinine level should be available in patients with an increased probability of a raised serum creatinine level (renal disease, renal surgery, proteinuria, diabetes mellitus, hypertension, gout, current intake of nephrotoxic drugs). A simple guideline has been produced. (orig.)

  14. Effect of nitrendipine on renal function and on hormonal parameters after intravascular iopromide

    DEFF Research Database (Denmark)

    Madsen, J K; Jensen, J W; Sandermann, J

    1998-01-01

    PURPOSE: To evaluate the effect of the low-molecular nonionic radiographic contrast agent iopromide (Ultravist) on renal function, vasoactive peptides (angiotensin II, aldosterone, arginine vasopressin, and atrial natriuretic factor (ANF)), and blood pressure, and to evaluate the influence....... Renal tubular function was estimated from the clearance of lithium. Hormones were measured by radioimmunoassays. RESULTS: Arteriography with iopromide did not change renal function. No differences between the nitrendipine and placebo groups were found in renal hemodynamics, tubular sodium handling...

  15. Phase Contrast Imaging

    International Nuclear Information System (INIS)

    Menk, Ralf Hendrik

    2008-01-01

    All standard (medical) x-ray imaging technologies, rely primarily on the amplitude properties of the incident radiation, and do not depend on its phase. This is unchanged since the discovery by Roentgen that the intensity of an x-ray beam, as measured by the exposure on a film, was related to the relative transmission properties of an object. However, recently various imaging techniques have emerged which depend on the phase of the x-rays as well as the amplitude. Phase becomes important when the beam is coherent and the imaging system is sensitive to interference phenomena. Significant new advances have been made in coherent optic theory and techniques, which now promise phase information in medical imaging. The development of perfect crystal optics and the increasing availability of synchrotron radiation facilities have contributed to a significant increase in the application of phase based imaging in materials and life sciences. Unique source characteristics such as high intensity, monochromaticity, coherence and high collimating provide an ideal source for advanced imaging. Phase contrast imaging has been applied in both projection and computed tomography modes, and recent applications have been made in the field of medical imaging. Due to the underlying principle of X-ray detection conventional image receptors register only intensities of wave fields and not their phases. During the last decade basically five different methods were developed that translate the phase information into intensity variations. These methods are based on measuring the phase shift φ directly (using interference phenomena), the gradient ∇ φ , or the Laplacian ∇ 2 φ. All three methods can be applied to polychromatic X-ray sources keeping in mind that the native source is synchrotron radiation, featuring monochromatic and reasonable coherent X-ray beams. Due to the vast difference in the coefficients that are driven absorption and phase effects (factor 1,000-10,000 in the energy

  16. A Randomized, Double-Blind, Placebo-Controlled, Phase 2b Study to Evaluate the Safety and Efficacy of Recombinant Human Soluble Thrombomodulin, ART-123, in Patients With Sepsis and Suspected Disseminated Intravascular Coagulation

    NARCIS (Netherlands)

    Vincent, Jean-Louis; Ramesh, Mayakonda K.; Ernest, David; Larosa, Steven P.; Pachl, Jan; Aikawa, Naoki; Hoste, Eric; Levy, Howard; Hirman, Joe; Levi, Marcel; Daga, Mradul; Kutsogiannis, Demetrios J.; Crowther, Mark; Bernard, Gordon R.; Devriendt, Jacques; Puigserver, Joan Vidal; Blanzaco, Daniel U.; Esmon, Charles T.; Parrillo, Joseph E.; Guzzi, Louis; Henderson, Seton J.; Pothirat, Chaicharn; Mehta, Parthiv; Fareed, Jawed; Talwar, Deepak; Tsuruta, Kazuhisa; Gorelick, Kenneth J.; Osawa, Yutaka; Kaul, Inder

    2013-01-01

    Objectives: To determine the safety and efficacy of recombinant thrombomodulin (ART-123) in patients with suspected sepsis-associated disseminated intravascular coagulation. Design: Phase 2b, international, multicenter, double-blind, randomized, placebo-controlled, parallel group, screening trial.

  17. The clinical importance and prediction of steal following femoro-femoral cross-over bypass: study of the donor iliac artery by intravascular ultrasound, arteriography, duplex scanning and pressure measurements

    DEFF Research Database (Denmark)

    Vogt, K C; Rasmussen, J G; Schroeder, T V

    2000-01-01

    to evaluate the clinical significance of the steal phenomenon following femoro-femoral bypass, and whether the addition of intravascular ultrasound (IVUS) to the established examinations of the donor iliac artery can improve the prediction of patients who will develop steal.......to evaluate the clinical significance of the steal phenomenon following femoro-femoral bypass, and whether the addition of intravascular ultrasound (IVUS) to the established examinations of the donor iliac artery can improve the prediction of patients who will develop steal....

  18. The Value of Contrast Echocardiography

    Directory of Open Access Journals (Sweden)

    Shannon C. Treiber

    2016-01-01

    Full Text Available Purpose: There is much evidence-based research proving the effectiveness of contrast echocardiography, but there are still questions and concerns about its specific uses. This study tested the effectiveness of contrast echocardiography in defining the left ventricular endocardial border. Methods: From 30 patients, a total of 60 echocardiograms –– 30 with and 30 without use of contrast –– were retrospectively reviewed by four blinded cardiologists with advanced training in echocardiography. No single cardiologist reviewed contrast and noncontrast images of the same patient. Each set of 30 echocardiograms was then studied for wall-motion scoring. Visualization of left ventricular wall segments and a global visualization confidence level of interpretation were recorded. Results: Of all wall segments (N = 510, 91% were visualized in echocardiograms with use of contrast, whereas 75% of the walls were visualized in echocardiograms without contrast (P < 0.001. Of 30 examinations, 17 contrast echocardiograms were read with high confidence compared to 6 without contrast use (P = 0.004. The number of walls visualized with contrast was increased in 18 patients (60%, whereas noncontrast echocardiograms yielded more visualized walls in 6 patients (20%, P = 0.002. Conclusions: This study demonstrates that contrast is valuable to echocardiographic imaging. Its use should be supported throughout echocardiography clinics and encouraged in certain patients for whom resting and stress echocardiography results without contrast often prove uninterpretable.

  19. One Patient, Two Uncommon B-Cell Neoplasms: Solitary Plasmacytoma following Complete Remission from Intravascular Large B-Cell Lymphoma Involving Central Nervous System

    Directory of Open Access Journals (Sweden)

    Joycelyn Lee

    2014-01-01

    Full Text Available Second lymphoid neoplasms are an uncommon but recognized feature of non-Hodgkin’s lymphomas, putatively arising secondary to common genetic or environmental risk factors. Previous limited evaluations of clonal relatedness between successive mature B-cell malignancies have yielded mixed results. We describe the case of a man with intravascular large B-cell lymphoma involving the central nervous system who went into clinical remission following immunochemotherapy and brain radiation, only to relapse 2 years later with a plasmacytoma of bone causing cauda equina syndrome. The plasmacytoma stained strongly for the cell cycle regulator cyclin D1 on immunohistochemistry, while the original intravascular large cell lymphoma was negative, a disparity providing no support for clonal identity between the 2 neoplasms. Continued efforts atcataloging and evaluating unique associations of B-cell malignancies are critical to improving understanding of overarching disease biology in B-cell malignancies.

  20. SIADH and partial hypopituitarism in a patient with intravascular large B-cell lymphoma: a rare cause of a common presentation

    Science.gov (United States)

    Akhtar, Simeen; Cheesman, Edmund; Jude, Edward B

    2013-01-01

    Hyponatraemia is a very common electrolyte abnormality with varied presenting features depending on the underlying cause. The authors report the case of a 75-year-old, previously fit, gentleman who presented with weight loss, lethargy and blackouts. He required four admissions to the hospital over an 8-month period. Investigations revealed persistent hyponatraemia consistent with a diagnosis of syndrome of inappropriate antidiuretic hormone secretion, macrocytic anaemia and partial hypopituitarism. Unfortunately, all other investigations that were performed failed to identify the underlying cause and a diagnosis of intravascular large B-cell lymphoma was only confirmed following postmortem studies. The authors recommend that endocrinologists should be involved at the outset in the management of patients with persistent hyponatraemia and that intravascular large B-cell lymphoma should be considered in the differential diagnosis of hyponatraemia. PMID:23362070

  1. Effects of computed tomography contrast medium factors on contrast enhancement

    International Nuclear Information System (INIS)

    Terasawa, Kazuaki; Hatcho, Atsushi; Okuda, Itsuko

    2011-01-01

    The various nonionic iodinated contrast media used in contrast computed tomography (CT) studies differ in terms of their composition, characteristics, and iodine concentration (mgI/ml), as well as the volume injected (ml). Compared with ionic iodinated contrast media, nonionic iodinated contrast media are low-osmolar agents, with different agents having different osmotic pressures. Using a custom-made phantom incorporating a semipermeable membrane, the osmotic flow rate (hounsfield unit (HU)/s) could easily be measured based on the observed increase in CT numbers, and the relationship between the osmotic pressure and the osmotic flow rate could be obtained (r 2 =0.84). In addition, taking the effects of patient size into consideration, the levels of contrast enhancement in the abdominal aorta (AA) and inferior vena cava (IVC) were compared among four types of CT contrast medium. The results showed differences in contrast enhancement in the IVC during the equilibrium phase depending on the type of contrast medium used. It was found that the factors responsible for the differences observed in enhancement in the IVC were the osmotic flow rate and the volume of the blood flow pathways in the circulatory system. It is therefore considered that the reproducibility of contrast enhancement is likely to be reduced in the examination of parenchymal organs, in which scanning must be performed during the equilibrium phase, even if the amount of iodine injected per unit body weight (mgI/kg) is maintained at a specified level. (author)

  2. Preintervention lesion remodelling affects operative mechanisms of balloon optimised directional coronary atherectomy procedures: a volumetric study with three dimensional intravascular ultrasound

    Science.gov (United States)

    von Birgelen, C; Mintz, G; de Vrey, E A; Serruys, P; Kimura, T; Nobuyoshi, M; Popma, J; Leon, M; Erbel, R; de Feyter, P J

    2000-01-01

    AIMS—To classify atherosclerotic coronary lesions on the basis of adequate or inadequate compensatory vascular enlargement, and to examine changes in lumen, plaque, and vessel volumes during balloon optimised directional coronary atherectomy procedures in relation to the state of adaptive remodelling before the intervention.
DESIGN—29 lesion segments in 29 patients were examined with intravascular ultrasound before and after successful balloon optimised directional coronary atherectomy procedures, and a validated volumetric intravascular ultrasound analysis was performed off-line to assess the atherosclerotic lesion remodelling and changes in plaque and vessel volumes that occurred during the intervention. Based on the intravascular ultrasound data, lesions were classified according to whether there was inadequate (group I) or adequate (group II) compensatory enlargement.
RESULTS—There was no significant difference in patient and lesion characteristics between groups I and II (n = 10 and 19), including lesion length and details of the intervention. Quantitative coronary angiographic data were similar for both groups. However, plaque and vessel volumes were significantly smaller in group I than in II. In group I, 9 (4)% (mean (SD)) of the plaque volume was ablated, while in group II 16 (11)% was ablated (p = 0.01). This difference was reflected in a lower lumen volume gain in group I than in group II (46 (18) mm3 v 80 (49) mm3 (p atherectomy procedures. Plaque ablation was found to be particularly low in lesions with inadequate compensatory vascular enlargement.


Keywords: intravascular ultrasound; ultrasonics; remodelling; coronary artery disease; atherectomy PMID:10648496

  3. Reliability of mechanical and phased-array designs for serial intravascular ultrasound examinations--animal and clinical studies in stented and non-stented coronary arteries.

    Science.gov (United States)

    Tardif, J C; Bertrand, O F; Mongrain, R; Lespérance, J; Grégoire, J; Paiement, P; Bonan, R

    2000-10-01

    Both mechanical and multi-element intravascular ultrasound designs have potential advantages and limitations that may impact on their value for clinical and research purposes. Determination of the reproducibility of measurements is critical before a given system can be used in studies such as regression of atherosclerosis trials. We performed serial intravascular ultrasound imaging with catheters using mechanical and phased-array designs in stented and non-stented coronary arteries in dogs and in patients. Both systems correlated well for areas (r > or = 0.90, p or = 0.84. p mechanical designs for measurements of area (mean difference in dogs and in patients: -0.24 and 0.96 mm2, p mechanical system (r > or = 0.96 for all measurements). The differences in absolute and relative variability between the mechanical and phased-array designs, both for reanalysis of same frames and serial pullbacks, were very small. Although multi-element and mechanical intravascular ultrasound designs are not strictly interchangeable, their similar reproducibility and the small differences in measurements demonstrate that both designs are acceptable alternatives for trials of regression of atherosclerosis. Determination of the variability for serial pullbacks of both designs was also important to assess the statistical power of such trials.

  4. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncica, Ana Maria; Saftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...

  5. Properties of conventional contrast media

    International Nuclear Information System (INIS)

    Muetzel, W.

    1981-01-01

    A comprehensive overview is given of the properties of contrast media currently used in computed tomography (CT). The chemical structure of the compounds and the physicochemical properties derived therefrom are described. Emphasis is placed on the importance of the physicochemical properties of contrast media for tolerance and the pharmacokinetic behavior of compounds in the body. An outline is given of the basic ideas governing rational use of contrast media in CT, which result from complex, time-dependent distribution of contrast media in different tissue spaces. (Auth.)

  6. Contrast-enhanced ultrasound in diagnosis and characterization of focal hepatic lesions.

    Science.gov (United States)

    Molins, Inés Gómez; Font, Juan Manuel Fernández; Alvaro, Juan Carrero; Navarro, Jose Luís Lledó; Gil, Marta Fernández; Rodríguez, Conrado M Fernández

    2010-12-28

    The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases, has led to an important increase in identification of focal liver lesions. The development of contrast-enhanced ultrasound (CEUS) opens a new window in the diagnosis and follow-up of these lesions. This technique offers obvious advantages over the computed tomography and magnetic resonance, without a decrease in its sensitivity and specificity. The new second generation contrast agents, due to their intravascular distribution, allow a continuous evaluation of the enhancement pattern, which is crucial in characterization of liver lesions. The dual blood supply in the liver shows three different phases, namely arterial, portal and late phases. The enhancement during portal and late phases can give important information about the lesion's behavior. Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis. The role of emerging techniques as a contrast-enhanced three-dimensional US is also discussed. In this article, the advantages, indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed.

  7. Atorvastatin and prevention of contrast induced nephropathy following coronary angiography

    Directory of Open Access Journals (Sweden)

    Peyman Bidram

    2015-01-01

    Full Text Available Background: Contrast induced nephropathy (CIN is one of the most common complications after radiographic procedures using intravascular radiocontrast media. The aim of the current study was to assess the effect of atorvastatin on prevention of CIN in patients undergoing coronary angiography. Materials and Methods: In a clinical trial study, 200 patients referred for angiography were randomly divided into two groups of using 80 mg atorvastatin and placebo before the procedure. Furthermore, 100 patients who were under chronic treatment of statins were included as the third group. Serum creatinine (Scr levels before and after the procedure were evaluated and incidence of CIN (post-procedural Scr of >0.5 mg/dl or >25% from baseline was assessed. Results: Mean age of the participants was 60.06 ± 0.69 years and 276 (92% were male. There were no significant differences between group with respect to age and gender. In pre-operation atorvastatin, placebo and long term statin groups, the incidence of CIN was 1%, 2% and 1%, and mean changes of Glomerular filtration rate (GFR was 3.68 ± 1.32, −0.77 ± 1.21 and 1.37 ± 0.86; and mean changes of creatinine (Cr was −0.05 ± 0.02, 0.02 ± 0.02 and −0.01 ± 0.01 respectively. (P = 0.776, 0.026 and 0.041 respectively. In pre-operation atorvastatin group, Cr decreased, and GFR increased significantly (P = 0.019 and 0.007 respectively. Conclusion: pre-operation short term high dose atorvastatin use was associated with a significant decrease in serum Cr level and increase in GFR after angiography.

  8. Effect of pre-donation fluid intake on fluid shift from interstitial to intravascular compartment in blood donors.

    Science.gov (United States)

    Deepika, Chenna; Murugesan, Mohandoss; Shastry, Shamee

    2018-02-01

    Fluid shifts from interstitial to intravascular space during blood donation helps in compensating the lost blood volume. We aimed to determine the volume of fluid shift following donation in donors with and without pre-donation fluid intake. We studied the fluid shift in 325 blood donors prospectively. Donors were divided in groups- with no fluid intake (GI) and either water (GII) or oral rehydrating fluids (GIII) before donation. Fluid shift following donation was calculated based on the difference between the pre and post donation blood volume. The influence of oral fluid intake, age, gender and body mass index (BMI) on volume of fluid shift was analyzed. The fluid shift was significant between donors without fluids (GI: 127 ± 81 ml) and donors with fluid intake (GII & III: 96 ± 45 ml) (p donation. As per our observation, the oral fluids before donation might not contribute to increase in fluid shift in blood donors after donation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Feasibility of Using Intravascular Ultrasonography for Assessment of Giant Cavernous Aneurysm after Endovascular Treatment: A Technical Report

    Science.gov (United States)

    Majidi, Shahram; Grigoryan, Mikayel; Tekle, Wondwossen G; Watanabe, Masaki; Qureshi, Adnan I

    2012-01-01

    Introduction Intravascular ultrasonography (IVUS) has been shown as a valuable adjunct imaging tool during endovascular procedures but its value in detection of any recurrence during follow up after endovascular coil embolization of large and giant intracranial aneurysms is not reported. Methods A 41 years old man who had been treated using stent assisted coil embolization for cavernous segment aneurysm of the left internal carotid artery underwent 60 month angiographic follow up. Concurrently, IVUS catheter was advanced under fluoroscopic guidance inside the cavernous portion of the left internal carotid artery. Then IVUS images were used to visualize the stent, coil loops, and aneurysm neck. Results The angiographic images were limited because of superimposition of the aneurysm on the parent vessel in all projections. IVUS images demonstrated that the stent was patent along its whole length and there was no sign of stent deformity or in-stent thrombosis. Loops of the coil were visualized as hyperechoic signals inside the aneurysm and there was no sign of herniated loops of coil inside the stent. Conclusion In this case report, we observed that adjunct use of IVUS can provide valuable information not ascertained by angiography during follow up assessment of coil embolized aneurysm. PMID:22737259

  10. Successful renal transplantation from a brain-dead deceased donor with head injury, disseminated intravascular coagulation and deranged renal functions

    Directory of Open Access Journals (Sweden)

    P P Ghuge

    2013-01-01

    Full Text Available Deceased donors (DDs with the brain death due to head injury are the major source of organs for transplantation. The incidence of post-head injury disseminated intravascular coagulation (DIC ranges from 24% to 50%. Many centers do not accept organs from donors with DIC due to increased risk of primary graft non-function and/or high chances of morbidity/mortality. We performed two successful renal transplants from a DD with head injury with DIC and deranged renal function. One of the recipients developed transient thrombocytopenia, but there was no evidence of DIC or delayed graft functions in either of the recipients. Over a follow-up of 1 month, both are doing well with stable graft function and hematological profile. Thus, a carefully selected DD with severe DIC even with deranged renal function is not a contraindication for organ donation if other risk factors for primary non-function are excluded. This approach will also help in overcoming organ shortage.

  11. Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

    Directory of Open Access Journals (Sweden)

    Varga Albert

    2011-06-01

    Full Text Available Abstract Background the clinical decision making could be difficult in patients with borderline lesions (visually assessed stenosis severity of 30 to 50% of the left main coronary artery (LM. The aim of the study was to evaluate the relationship between transthoracic Doppler (TTDE peak diastolic flow velocity (PDV and intravascular ultrasound (IVUS measurements in the assessment of angiographically borderline LM lesions. Methods 27 patients (mean age 64 ± 8 years, 21 males with borderline LM stenosis referred for IVUS examination were included in the study. We performed standard IVUS with minimal lumen area (MLA and plaque burden (PB measurement and routine quantitative coronary angiography (QCA with diameter stenosis (%DS and area stenosis (%AS assessment in all. During TTDE, resting PDV was measured in the LM. Results interpretable Doppler signal could be obtained in 24 patients (88% feasibility; therefore these patients entered the final analysis. MLA was 7.1 ± 2.7 mm2. TTDE measured PDV correlated significantly with IVUS-derived MLA (r = -0.46, p 2 LM stenosis. Conclusion In angiographically borderline LM disease, resting PDV from transthoracic echocardiography is increased in presence of increased plaque burden by IVUS. TTDE evaluation might be a useful adjunct to other invasive and non-invasive methods in the assessment of borderline LM lesions. Further, large scale studies are needed to establish the exact cut-off value of PDV for routine clinical application.

  12. Mechanism of lumen gain with a novel rotational aspiration atherectomy system for peripheral arterial disease: examination by intravascular ultrasound.

    Science.gov (United States)

    Hassan, Ali H M; Ako, Junya; Waseda, Katsuhisa; Honda, Yasuhiro; Zeller, Thomas; Leon, Martin B; Fitzgerald, Peter J

    2010-01-01

    The purpose of this study was to evaluate the mechanism of luminal gain with a novel atheroablation system (Pathway PV) for the treatment of peripheral artery disease using intravascular ultrasound (IVUS). The atherectomy system is a rotational atherectomy device, which employs expandable rotating blades with ports that allow flushing and aspiration of the plaque material or thrombus. In this first-in-man clinical study, IVUS analysis was available in 6 patients with lower limb ischemia treated with this device. The treatment results were assessed using IVUS at pre and post atherectomy. Lumen beyond burr size (LBB) was defined as lumen gain divided by the estimated burr area determined by the burr-size. IVUS analysis was available in six patients (superficial femoral artery n=3, popliteal artery n=2, posterior tibial artery n=1). Atheroablation achieved a significant increase in lumen area (LA) (preintervention 3.9+/-0.4, postatheroablation 8.0+/-1.7 mm(2), Patherectomy device achieved significant luminal gain by debulking in the absence of vessel stretching. The LA was greater than burr-sized lumen expectancy at cross-sections along the treated segments, suggesting a complimentary role of aspiration in luminal gain in atherosclerotic peripheral artery lesions.

  13. Performance Evaluation of Five Different Disseminated Intravascular Coagulation (DIC) Diagnostic Criteria for Predicting Mortality in Patients with Complicated Sepsis.

    Science.gov (United States)

    Ha, Sang Ook; Park, Sang Hyuk; Hong, Sang Bum; Jang, Seongsoo

    2016-11-01

    Disseminated intravascular coagulation (DIC) is a major complication in sepsis patients. We compared the performance of five DIC diagnostic criteria, focusing on the prediction of mortality. One hundred patients with severe sepsis or septic shock admitted to intensive care unit (ICU) were enrolled. Routine DIC laboratory tests were performed over the first 4 days after admission. The overall ICU and 28-day mortality in DIC patients diagnosed from five criteria (International Society on Thrombosis and Haemostasis [ISTH], the Japanese Association for Acute Medicine [JAAM], the revised JAAM [R-JAAM], the Japanese Ministry of Health and Welfare [JMHW] and the Korean Society on Thrombosis and Hemostasis [KSTH]) were compared. Both KSTH and JMHW criteria showed superior performance than ISTH, JAAM and R-JAAM criteria in the prediction of overall ICU mortality in DIC patients (odds ratio 3.828 and 5.181, P = 0.018 and 0.006, 95% confidence interval 1.256-11.667 and 1.622-16.554, respectively) when applied at day 1 after admission, and survival analysis demonstrated significant prognostic impact of KSTH and JMHW criteria on the prediction of 28-day mortality (P = 0.007 and 0.049, respectively) when applied at day 1 after admission. In conclusion, both KSTH and JMHW criteria would be more useful than other three criteria in predicting prognosis in DIC patients with severe sepsis or septic shock.

  14. Serotonin syndrome, disseminated intravascular coagulation, and hepatitis after a single ingestion of MDMA in an Asian woman.

    Science.gov (United States)

    Nadkarni, Girish N; Hoskote, Sumedh S; Piotrkowski, Jared; Annapureddy, Narender

    2014-01-01

    N-Methyl-3,4-methylenedioxyamphetamine (MDMA), also called "Ecstasy," is a commonly abused psychoactive drug among the American youth. We present the case of a 23-year-old Korean-American woman who presented with seizure, delirium, and rigidity after MDMA ingestion. She was febrile (38.7°C), tachycardic (188 beats/min), tachypneic (26 breaths/min) with a borderline blood pressure (95/43 mm Hg). Examination revealed generalized muscle rigidity, tremors, hyperreflexia, and ocular clonus, leading to the diagnosis of serotonin syndrome. Urine toxicology screen was only positive for amphetamines, consistent with the history of MDMA ingestion. Initial laboratory testing showed thrombocytopenia, further testing showed deranged prothrombin time, partial thromboplastin time, decreased fibrinogen, and elevated D-dimer, suggesting disseminated intravascular coagulation. Hepatic transaminases trended up dramatically reflecting acute hepatitis. The patient received supportive care and improved by hospital day 3. MDMA toxicity manifested as serotonin syndrome, hepatitis, and coagulopathy is exceedingly rare. MDMA is metabolized by the hepatic CYP2D6 enzyme. Certain populations, such as Koreans, Chinese, and Japanese have a high prevalence of a polymorphism that confers reduced enzyme activity. We discuss this hypothesis as a possible cause for this severe presentation in our patient after a single ingestion.

  15. Monte Carlo dose calculations of beta-emitting sources for intravascular brachytherapy: a comparison between EGS4, EGSnrc, and MCNP.

    Science.gov (United States)

    Wang, R; Li, X A

    2001-02-01

    The dose parameters for the beta-particle emitting 90Sr/90Y source for intravascular brachytherapy (IVBT) have been calculated by different investigators. At a distant distance from the source, noticeable differences are seen in these parameters calculated using different Monte Carlo codes. The purpose of this work is to quantify as well as to understand these differences. We have compared a series of calculations using an EGS4, an EGSnrc, and the MCNP Monte Carlo codes. Data calculated and compared include the depth dose curve for a broad parallel beam of electrons, and radial dose distributions for point electron sources (monoenergetic or polyenergetic) and for a real 90Sr/90Y source. For the 90Sr/90Y source, the doses at the reference position (2 mm radial distance) calculated by the three code agree within 2%. However, the differences between the dose calculated by the three codes can be over 20% in the radial distance range interested in IVBT. The difference increases with radial distance from source, and reaches 30% at the tail of dose curve. These differences may be partially attributed to the different multiple scattering theories and Monte Carlo models for electron transport adopted in these three codes. Doses calculated by the EGSnrc code are more accurate than those by the EGS4. The two calculations agree within 5% for radial distance <6 mm.

  16. The Precise Determination of Vascular Lumen and Stent Diameters: Correlation Among Calibrated Angiography, Intravascular Ultrasound, and Pressure-Fixed Specimens

    International Nuclear Information System (INIS)

    Froelich, Jens J.; Hoppe, Martin; Nahrstedt, Christoph; Barth, Klemens H.; Wagner, H. Joachim; Klose, Klaus J.

    1997-01-01

    Purpose: Luminal diameters measured in vivo by calibrated-catheter angiography and by intravascular ultrasound were correlated with those obtained from pressure-fixed histologic cross-sections to determine the accuracy of both methods. Methods: Angiographic and endosonographic diameter measurements were performed in the center of stents placed in the iliac arteries of 10 miniature pigs and were compared with luminal and stent diameters in postmortem, pressure-fixed, histologic cross-sections from identical locations. Results: Compared with histologic diameters, magnification-corrected angiographic measurements still magnified vascular luminal diameters by 0.7 ± 0.71 mm (r= 0.41, Pearson; p 0.5, Wilcoxon, matched pairs). Similarly, stent diameters correlated well between endosonographic and histologic measurements (r= 0.91; p= 0.002), and less well between angiographic and histologic diameters (r= 0.62; p= 0.002). Conclusion: Since calibrated angiography still overestimates vascular lumina, endosonography is the preferred technique for accurate in vivo measurements

  17. Results of a randomized controlled pilot trial of intravascular renal denervation for management of treatment-resistant hypertension.

    Science.gov (United States)

    Jacobs, Lotte; Persu, Alexandre; Huang, Qi-Fang; Lengelé, Jean-Philippe; Thijs, Lutgarde; Hammer, Frank; Yang, Wen-Yi; Zhang, Zhen-Yu; Renkin, Jean; Sinnaeve, Peter; Wei, Fang-Fei; Pasquet, Agnès; Fadl Elmula, Fadl Elmula M; Carlier, Marc; Elvan, Arif; Wunder, Cora; Kjeldsen, Sverre E; Toennes, Stefan W; Janssens, Stefan; Verhamme, Peter; Staessen, Jan A

    2017-12-01

    Previous trials of catheter-based renal-artery denervation (RDN) as treatment modality in resistant hypertension (rHT) generated unconvincing results. In the Investigator-Steered Project on Intravascular Denervation for Management of Treatment-Resistant Hypertension (INSPiRED; NCT01505010), we optimized selection and management of rHT patients. With ethical clearance to randomize 18 patients, three Belgian hypertension centers screened 29 rHT patients on treatment with ≥3 drugs, of whom 17 after optimization of treatment (age efficacy endpoint, and 2.5 mL/min/1.73 m 2 (+1.5 vs. -1.1 mL/min/1.73 m 2 ; P = .86) for eGFR, the primary safety endpoint. At 6 month, ECG voltages and the number of prescribed drugs (P ≤ .036) were lower in RDN patients, but quality of life and adherence, captured by questionnaire and urine analysis were similar in both groups. Changes in BP and adherence were unrelated. No major complications occurred. The INSPiRED pilot suggests that RDN with the EnligHTN ™ system is effective and safe and generated insights useful for the design of future RDN trials.

  18. Intravascular streaming and variable delivery to brain following carotid artery infusions in the Sprague-Dawley rat

    International Nuclear Information System (INIS)

    Saris, S.C.; Wright, D.C.; Oldfield, E.H.; Blasberg, R.G.

    1988-01-01

    Intracarotid artery infusions in animals are commonly performed in studies of the blood-brain barrier and in chemotherapy trials. Implicit in the analysis of these experiments is that the infusate will be distributed to the territory of the internal carotid artery in a manner that is proportional to blood flow. Fifteen Sprague-Dawley rats were studied to determine if poor infusate mixing with blood due to intravascular streaming occurred during intracarotid artery drug infusions and if it could be eliminated with fast retrograde infusion. In three experimental groups, a radiolabeled flow tracer-- 14 C-iodoantipyrine (IAP)--was infused retrograde through the external carotid artery into the common carotid artery at slow, medium, and fast rates (0.45, 1.5, and 5.0 ml/min). In a control group, IAP was injected intravenously (i.v.). Local isotope concentrations in the brain were determined by quantitative autoradiography, and the variability of isotope delivery was assessed in the frontoparietal cortex, temporal cortex, and caudate putamen of all animals. Streaming phenomena were manifest in all selected anatomic areas after the slow and medium rates of intraarterial infusion. After fast intracarotid infusion or i.v. injection, there was uniform distribution of isotope in the same brain regions

  19. Detection of attenuated plaque in stable angina with 64-multidetector computed tomography: a comparison with intravascular ultrasound.

    Science.gov (United States)

    Jinzaki, Masahiro; Okabe, Teruo; Endo, Ayaka; Kawamura, Akio; Koga, Seiko; Yamada, Minoru; Fukuda, Keiichi; Kuribayashi, Sachio

    2012-01-01

    To clarify multidetector computed tomography (MDCT) findings of attenuated plaque detected by intravascular ultrasound (IVUS). One hundred and fifty-four patients with stable angina underwent MDCT before IVUS. The attenuated plaque was identified in the targeted artery with IVUS, and the same artery was analyzed with MDCT for the presence of a high density area (HDA) >130 Hounsfield units (HU), and a low density area (LDA) HDA in attenuated plaque was compared with that in calcified plaque. Ten attenuated plaques and 15 calcified plaques were identified in 9 of 154 patients (males=9, 66.2 ± 9.5 years). Eight of the 10 attenuated plaques and all 15 calcified plaques were accompanied with a HDA on MDCT. The HDA ranged from 174 to 667 HU (mean 389.0 ± 148.3 HU) in the 8 attenuated plaques, and from 545 to 1,205 HU (mean 920.9 ± 215.9 HU) in 15 calcified plaques. There was a significant difference in CT density of the HDA between the attenuated and calcified plaque (PHDA. MDCT has the ability to demonstrate attenuated plaque as the combination of HDA (approximately 400 HU on average) and LDA HDA can be differentiated from calcified plaque by its lower CT density value.

  20. In vivo evaluation of axial integrity of coronary stents using intravascular ultrasound: Insights on longitudinal stent deformation.

    Science.gov (United States)

    Dvir, Danny; Kitabata, Hironori; Barbash, Israel M; Minha, Sa'ar; Badr, Salem; Loh, Joshua P; Chen, Fang; Torguson, Rebecca; Waksman, Ron

    2014-09-01

    To evaluate the axial integrity of different coronary stents using intravascular ultrasound (IVUS). Longitudinal stent deformation was recently reported. Consecutive patients who underwent IVUS analysis after drug-eluting stent (DES) implantation for de novo coronary lesions were evaluated. Stent length was compared with label length for calculation of absolute change and relative difference (absolute change divided by label length). A total of 233 DES utilizing five different platforms were included. The median absolute change in stent length was 0.90 mm (interquartile range [IQR] 0.48-1.39) and the relative difference was 5.24% (IQR 2.55-8.29). There was no significant difference among the groups in median absolute or relative change: Cypher 0.89 mm/3.89%, Taxus 0.88 mm/5.39%, Endeavor 1.16 mm/6.77%, Xience V 0.86 mm/5.80%, and PROMUS Element 0.79 mm/5.34% (P = 0.085, P = 0.072, respectively). Multivariate logistic regression revealed that the Cypher stent was independently correlated with a lower change in length, whereas stent label length and deployment pressure were correlated with higher absolute change. The axial integrity of DES platforms examined in vivo was high, with only mild changes in stent length after implantation. While there are differences between first- and second-generation DES, axial integrity among second-generation DES was similar. © 2013 Wiley Periodicals, Inc.

  1. Chronic intravascular coagulation associated with chronic myelocytic leukemia. Use of heparin in connection with a surgical procedure.

    Science.gov (United States)

    German, H J; Smith, J A; Lindenbaum, J

    1976-10-01

    A women with Philadelphia chromosome-positive chronic myelocytic leukemia lived nearly 12 years from the time of diagnosis. During most of this period she received no therapy, and marked cyclic oscillations in the white blood cell count were documented. The last two years of her illness were marked by a hemorrhagic disorder associated with hypofibrinogenemia, thrombocytopenia, increased plasma fibrinopeptide A concentration and markedly elevated serum levels of fibrin degradation products. The coagulation disorder was rapidly reversible on several occasions with heparin therapy. After treatment with heparin and platelet transfusions, the patient underwent successful resection of a large ovarian cyst with excellent hemostasis during the procedure. Postoperatively, the administration of heparin and platelets was discontinued and a large wound hematoma developed. After resumption of therapy with heparin and platelets, the remainder of her postoperative course was uneventful. The literature on the subject is reviewed and tentative guidelines are offered concerning the management of patients with intravascular coagulation who require diagnostic or therapeutic surgical procedures.

  2. Accuracy of multidetector row computed tomography for the detection of transplant vasculopathy: comparison with invasive coronary angiography and intravascular ultrasound

    International Nuclear Information System (INIS)

    Carrascosa, P.; Capunay, C.; Carrascosa, J.; Perrone, S.; Deviggiano, A.; Lopez, E.M.; Lev, G.; Garcia, M.J.

    2009-01-01

    Objective: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for detection of luminal stenosis and cardiac allograft vasculopathy in comparison with coronary angiography (CA) and intravascular ultrasound (IVUS) respectively. Material and methods: Nineteen cardiac transplant patients scheduled for follow-up CA were included. MDCT coronary angiography was performed using a 16-row CT scanner within 7-14 days after CA and IVUS. Studies were analyzed by independent readers; two observers evaluated the CT datasets for the presence of coronary artery stenosis > 50% and allograft vasculopathy. Results: The sensitivity for detecting > 50% luminal stenosis was 80-88% and specificity, 98-99% and for detection of cardiac allograft vasculopathy, the sensitivity was 91-96% and specificity, 88-91%. Conclusion: In this preliminary series, our results indicate that MDCT coronary angiography was capable of detecting both significant coronary stenosis as well as diffuse intimal proliferation. This non-invasive procedure could be an alternative to CA and IVUS in the surveillance of heart transplant patients. (authors) [es

  3. A novel microbubble construct for intracardiac or intravascular MR manometry: a theoretical study

    International Nuclear Information System (INIS)

    Dharmakumar, Rohan; Plewes, Donald B; Wright, Graham A

    2005-01-01

    It has been demonstrated that gas-filled microbubble contrast agents, based on their volume changes, can serve as pressure probes in an MR field. It was recently reported that such an MR-based pressure measurement with microbubbles at 1.5 T must make use of microbubbles that have a volumetric magnetic susceptibility difference with the blood of at least 34 ppm in SI units. In this work, we show through analytical approximations and numerical simulations that such a microbubble formulation can be achieved by coating typical lipid-shelled microbubbles with particles of high dipole moment. Through finite-element simulations we demonstrate that the effective volumetric magnetic susceptibility of a coated microbubble is dependent on the radius, the shell volume fraction and the magnetic susceptibility of the particulates on the shell. Our calculations suggest that a suitable microbubble formulation which will be MR-sensitive to small pressure changes at 1.5 T must be 2-3 μm in radius and be uniformly coated with single-domain magnetic nanoparticles, such as magnetite, at shell volume fractions below 5%

  4. The new numbers contrast sensitivity chart for contrast sensitivity measurement

    Directory of Open Access Journals (Sweden)

    Bharkbhum Khambhiphant

    2011-10-01

    Conclusions: These charts show reasonable agreement and can be used interchangeably with the MARS. It is helpful for Thai people who can only read numbers in doing the test. We can use them in routinely contrast sensitivity measurement.

  5. Adriamycin nephrosis and contrast media

    International Nuclear Information System (INIS)

    Thomsen, H.S.; Golman, K.; Hemmingsen, L.; Larsen, S.; Skaarup, P.; Koebenhavns Amts Sygehus, Herlev; Koebenhavns Amts Sygehus, Herlev; Centralsygehuset, Nykoebing Falster; Malmoe Allmaenna Sjukhus

    1990-01-01

    Urine profiles (albumin, glucose, NAG, LDH, GGT and sodium) were followed for 9 days after intravenous injection of either diatrizoate, iohexol, or saline in 27 Wistar rats with nephrosis induced by Adriamycin 42 days before. Another 9 rats exposed to neither Adriamycin nor contrast media served as controls. None of the contrast media caused further increased albuminuria of significance, whereas both induced significantly increased excretion of all 5 tubular components. The excretion of NAG and sodium was significantly higher following diatrizoate than following iohexol. From 24 h post injection there was no significantly greater excretion of any of the components after either diatrizoate or iohexol than after saline among the rats given Adriamycin. At the end of day 9 after contrast medium injection neither serum sodium, potassium, glucose, urea, creatinine, nor albumin revealed any contrast media related changes. Kidney histology showed quantitatively larger lesions in kidneys exposed to Adriamycin and contrast media than in kidneys exposed to Adriamycin and saline. There were no differences between the two contrast media groups. It is thus concluded, that both high osmolar ionic and low osmolar non-ionic contrast media cause temporary tubular dysfunction but no further glomerular dysfunction in rats with nephrosis induced by Adriamycin. The histologic findings indicate that both media may worsen non-reversible renal lesions. (orig.)

  6. Contrast-enhanced MR angiography of abdominal vessels: Is there still a role for angiography?

    Energy Technology Data Exchange (ETDEWEB)

    Vosshenrich, R.; Fischer, U. [Department of Radiology, Georg-August-Universitaet Goettingen (Germany)

    2002-01-01

    The purpose of this review article is to describe recent advantages in contrast-enhanced (CE) three-dimensional (3D) magnetic resonance angiography (MRA) in comparison with other vascular imaging techniques, and to discuss their current clinical applications for the imaging of abdominal vessels. Principles and technical considerations are presented and clinical applications are reviewed for different vascular diseases. In ruptured aortic aneurysms and acute dissections CT is the method of first choice. Contrast-enhanced 3D MRA can be well used for therapeutic planning and follow-up in patients with stable disease. A comprehensive MR examination including CE 3D MRA, MR urography and MR nephrogram has the potential to replace the conventional studies for the evaluation of renal vascular disease. It is an accurate method for imaging the origins of coeliac and superior mesenteric arteries, although the image resolution is too low for reliable assessment of the inferior mesenteric artery. Contrast-enhanced 3D MRA has emerged as the method of choice for studying the portal venous system in liver transplant recipients, in patients with portal hypertension and in cases with abdominal tumours for preoperative evaluation. Additional non-invasive flow measurements are useful in monitoring portal hypertension. The abdominal veins can be well imaged using unenhanced MR techniques. Imaging may be facilitated with intravascular contrast media. Contrast-enhanced 3D MRA can replace intra-arterial DSA for diagnosis, therapy planning and follow-up in patients with abdominal vascular disease. Catheter-based arteriography will still be used for interventional procedures such as percutaneous transluminal angioplasty, stent placement and embolisation. (orig.)

  7. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncică, Ana Maria; Săftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...... cancers and visualization of the portal venous system and esophageal varices. In addition, contrast agents can be used to differentiate pancreatic lesions. The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies. The sensitivity of power Doppler...

  8. Pathogenic factors associated with development of disseminated intravascular coagulopathy (DIC) in a tertiary academic hospital in South Africa.

    Science.gov (United States)

    Mayne, Elizabeth S; Mayne, Anthony L H; Louw, Susan J

    2018-01-01

    Disseminated intravascular coagulopathy (DIC) is a thrombotic microangiopathy arising from consumption of both coagulation factors and platelets. DIC is triggered by a number of clinical conditions including severe infection, trauma and obstetric complications. Early diagnosis and treatment of the underlying condition is paramount. A high clinical index of suspicion is needed to ensure that patients at risk of developing DIC are appropriately investigated. In order to establish the clinical conditions most frequently associated with DIC, we reviewed all DIC screens received at a tertiary hospital in Johannesburg, South Africa over a 1 year period. The commonest clinical condition associated with DIC in our population was infection with 84% of patients infected with an identified pathogen. The most frequently diagnosed pathogen was HIV followed by Mycobacterium tuberculosis and other bacterial infections. In the majority of cases, bacteria were isolated from blood cultures. In 47 patients, HIV was the only pathogen which could be isolated. A relative risk ratio of 2.73 and an odds ratio of 29.97 was attributed to HIV for development of a DIC. A malignancy was present in 51 of the patients of which approximately 60% had co-existing infection. No cause could be attributed in 30 patients. Infection was identified in the majority of the patients diagnosed with DIC in this study. HIV showed the highest relative risk ratio of all pathogens although previous studies have not suggested that HIV was strongly associated with DIC. In almost half of the HIV infected patients, there was no other pathogen isolated despite extensive investigation. This suggests that HIV has a strong association with the development of DIC, warranting further research into the relationship between HIV and disseminated microvascular thrombosis.

  9. Automatic segmentation and 3D reconstruction of intravascular ultrasound images for a fast preliminar evaluation of vessel pathologies.

    Science.gov (United States)

    Sanz-Requena, Roberto; Moratal, David; García-Sánchez, Diego Ramón; Bodí, Vicente; Rieta, José Joaquín; Sanchis, Juan Manuel

    2007-03-01

    Intravascular ultrasound (IVUS) imaging is used along with X-ray coronary angiography to detect vessel pathologies. Manual analysis of IVUS images is slow and time-consuming and it is not feasible for clinical purposes. A semi-automated method is proposed to generate 3D reconstructions from IVUS video sequences, so that a fast diagnose can be easily done, quantifying plaque length and severity as well as plaque volume of the vessels under study. The methodology described in this work has four steps: a pre-processing of IVUS images, a segmentation of media-adventitia contour, a detection of intima and plaque and a 3D reconstruction of the vessel. Preprocessing is intended to remove noise from the images without blurring the edges. Segmentation of media-adventitia contour is achieved using active contours (snakes). In particular, we use the gradient vector flow (GVF) as external force for the snakes. The detection of lumen border is obtained taking into account gray-level information of the inner part of the previously detected contours. A knowledge-based approach is used to determine which level of gray corresponds statistically to the different regions of interest: intima, plaque and lumen. The catheter region is automatically discarded. An estimate of plaque type is also given. Finally, 3D reconstruction of all detected regions is made. The suitability of this methodology has been verified for the analysis and visualization of plaque length, stenosis severity, automatic detection of the most problematic regions, calculus of plaque volumes and a preliminary estimation of plaque type obtaining for automatic measures of lumen and vessel area an average error smaller than 1mm(2) (equivalent aproximately to 10% of the average measure), for calculus of plaque and lumen volume errors smaller than 0.5mm(3) (equivalent approximately to 20% of the average measure) and for plaque type estimates a mismatch of less than 8% in the analysed frames.

  10. Newly Developed Biocompatible Material: Dispersible Titanium-Doped Hydroxyapatite Nanoparticles Suitable for Antibacterial Coating on Intravascular Catheters.

    Science.gov (United States)

    Furuzono, Tsutomu; Okazaki, Masatoshi; Azuma, Yoshinao; Iwasaki, Mitsunobu; Kogai, Yasumichi; Sawa, Yoshiki

    2017-01-01

    Thirteen patients with chlorhexidine-silver sulfadiazine-impregnated catheters have experienced serious anaphylactic shock in Japan. These adverse reactions highlight the lack of commercially available catheters impregnated with strong antibacterial chemical agents. A system should be developed that can control both biocompatibility and antibacterial activity. Hydroxyapatite (HAp) is biocompatible with bone and skin tissues. To provide antibacterial activity by using an external physical stimulus, titanium (Ti) ions were doped into the HAp structure. Highly dispersible, Ti-doped HAp (Ti-HAp) nanoparticles suitable as a coating material were developed. In 3 kinds of Ti-HAp [Ti/(Ca + Ti) = 0.05, 0.1, 0.2], the Ti content in the HAp was approximately 70% of that used in the Ti-HAp preparation, as determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). ICP-AES and X-ray diffraction showed Ti ions were well substituted into the HAp lattice. The nanoparticles were almost uniformly coated on a polyethylene (PE) sheet in a near-monolayer with a surface coverage ratio >95%. The antibacterial activity of the Ti-HAp nanoparticles containing 7.3% Ti ions and coating the sheet was evaluated by calculating the survival ratio of Pseudomonas aeruginosa on the coated sheet after ultraviolet (UV) irradiation. The Ti-HAp-coated sheet showed a 50% decrease in the number of P. aeruginosa compared with that on an uncoated control PE sheet after UV irradiation for 30 s. Key Messages: A system of biocompatibility and antibacterial activity with an on/off switch controlled by external UV stimulation was developed. The system is expected to be applicable in long-term implanted intravascular catheters. © 2017 S. Karger AG, Basel.

  11. Prothrombin Time, Activated Partial Thromboplastin Time, Fibrinogen, dan D-dimer Sebagai Prediktor Decompensated Disseminated Intravascular Coagulation Sisseminated pada Sepsis

    Directory of Open Access Journals (Sweden)

    Fenny

    2011-03-01

    Full Text Available Sepsis is a systemic response to infection especially in pneumonia case. Sepsis can cause complications such as disseminated intravascular coagulation (DIC which can be divided into compensated and decompensated DIC. The purpose of this study was to assess whether the value of prothrombin time (PT, activated partial thromboplastin time (aPTT, fibrinogen, and D-dimer levels can be used as predictors of decompensated DIC in sepsis patients. This study was conducted at the Laboratory of Clinical Pathology Rumah Sakit Hasan Sadikin Bandung since September 2008 to June 2010. Subjects were patients with sepsis caused by pneumonia. PT and aPTT values, fibrinogen, and D-dimer levels was recorded from all sepsis patients then patients were observed until diagnosed decompensated or non-decompensated DIC, then the value of PT, aPTT, fibrinogen and D-dimer levels in the group of decompensated DIC and non-decompensated DIC were analysed. This study used cohort design. Subjects were 39 sepsis patients (58% with outcome decompensated DIC and 28 sepsis patients (42% with outcome non-decompensated DIC. From the hemostasis parameter test out, it was found that PT, aPTT, and fibrinogen were the predictor of decompensated DIC in patients with sepsis with relative risk 240.500, 7.157, and 6.421; respectively. Conclusions, prothrombin time, aPTT, fibrinogen are the test to know coagulation activation. Hemostasis parameter to predict decompensated DIC in sepsis patients are the shorten PT, aPTT, and the increased fibrinogen

  12. A study of coronary artery rotational motion with dense scale-space optical flow in intravascular ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Danilouchkine, M G; Mastik, F; Steen, A F W van der [Department of Biomedical Engineering, Erasmus Medical Center, Ee2302, PO Box 2040, 3000 CA, Rotterdam (Netherlands)], E-mail: m.danilouchkine@ErasmusMC.nl, E-mail: f.mastik@ErasmusMC.nl, E-mail: a.vandersteen@ErasmusMC.nl

    2009-03-21

    This paper describes a novel method for estimating tissue motion in two-dimensional intravascular ultrasound (IVUS) images of a coronary artery. It is based on the classical Lukas-Kanade (LK) algorithm for optical flow (OF). The OF vector field quantifies the amount of misalignment between two consecutive frames in a sequence of images. From the theoretical standpoint, two fundamental improvements are proposed in this paper. First, using a simplified representation of the vessel wall as a medium with randomly distributed scatterers, it was shown that the OF equation satisfies the integral brightness conservation law. Second, a scale-space embedding for the OF equation was derived under the assumption of spatial consistency in IVUS acquisitions. The spatial coherence is equivalent to a locally affine motion model. The latter effectively captures and appropriately describes a complex deformation pattern of the coronary vessel wall under the varying physiological conditions (i.e. pulsatile blood pressure). The accuracy of OF tracking was estimated on the tissue-mimicking phantoms subjected to the controlled amount of angular deviation. Moreover, the performance of the classical LK and proposed approach was compared using the simulated IVUS images with an atherosclerotic lesion. The experimental results showed robust and reliable performance of up to 5{sup 0} of rotation, which is within the plausible range of circumferential displacement of the coronary arteries. Subsequently, the algorithm was used to analyze vessel wall motion in 18 IVUS pullbacks from 16 patients. The in vivo experiments revealed that the motion of coronary arteries is primarily determined by the cardiac contraction.

  13. Lumen and calcium characteristics within calcified coronary lesions. Comparison of computed tomography coronary angiography versus intravascular ultrasound.

    Science.gov (United States)

    Noll, Dariusz; Kruk, Mariusz; Pręgowski, Jerzy; Kaczmarska, Edyta; Kryczka, Karolina; Pracoń, Radosław; Skwarek, Mirosław; Dzielińska, Zofia; Petryka, Joanna; Spiewak, Mateusz; Lubiszewska, Barbara; Norwa-Otto, Bożena; Opolski, Maksymilian; Witkowski, Adam; Demkow, Marcin; Rużyłło, Witold; Kępka, Cezary

    2013-01-01

    Computed tomography coronary angiography (CTCA) is a diagnostic method used for exclusion of coronary artery disease. However, lower accuracy of CTCA in assessment of calcified lesions is a significant factor impeding applicability of CTCA for assessment of coronary atherosclerosis. To provide insight into lumen and calcium characteristics assessed with CTCA, we compared these parameters to the reference of intravascular ultrasound (IVUS). Two hundred and fifty-two calcified lesions within 97 arteries of 60 patients (19 women, age 63 ±10 years) underwent assessment with both 2 × 64 slice CT (Somatom Definition, Siemens) and IVUS (s5, Volcano Corp.). Coronary lumen and calcium dimensions within calcified lesions were assessed with CTCA and compared to the reference measurements made with IVUS. On average CTCA underestimated mean lumen diameter (2.8 ±0.7 mm vs. 2.9 ±0.8 mm for IVUS), lumen area (6.4 ±3.4 mm(2) vs. 7.0 ±3.7 mm(2) for IVUS, p < 0.001) and total calcium arc (52 ±35° vs. 83 ±54°). However, analysis of tertiles of the examined parameters revealed that the mean lumen diameter, lumen area and calcium arc did not significantly differ between CTCA and IVUS within the smallest lumens (1(st) tertile of mean lumen diameter at 2.1 mm, and 1(st) tertile of lumen area at 3.7 mm(2)) and lowest calcium arc (mean of 40°). Although, on average, CTCA underestimates lumen diameter and area as well as calcium arc within calcified lesions, the differences are not significant within the smallest vessels and calcium arcs. The low diagnostic accuracy of CTCA within calcified lesions may be attributed to high variance and not to systematic error of measurements.

  14. Near-Infrared Spectroscopy Enhances Intravascular Ultrasound Assessment of Vulnerable Coronary Plaque: A Combined Pathological and In Vivo Study.

    Science.gov (United States)

    Puri, Rishi; Madder, Ryan D; Madden, Sean P; Sum, Stephen T; Wolski, Kathy; Muller, James E; Andrews, Jordan; King, Karilane L; Kataoka, Yu; Uno, Kiyoko; Kapadia, Samir R; Tuzcu, E Murat; Nissen, Steven E; Virmani, Renu; Maehara, Akiko; Mintz, Gary S; Nicholls, Stephen J

    2015-11-01

    Pathological studies demonstrate the dual significance of plaque burden (PB) and lipid composition for mediating coronary plaque vulnerability. We evaluated relationships between intravascular ultrasound (IVUS)-derived PB and arterial remodeling with near-infrared spectroscopy (NIRS)-derived lipid content in ex vivo and in vivo human coronary arteries. Ex vivo coronary NIRS and IVUS imaging was performed through blood in 116 coronary arteries of 51 autopsied hearts, followed by 2-mm block sectioning (n=2070) and histological grading according to modified American Heart Association criteria. Lesions were defined as the most heavily diseased 2-mm block per imaged artery on IVUS. IVUS-derived PB and NIRS-derived lipid core burden index (LCBI) of each block and lesion were analyzed. Block-level analysis demonstrated significant trends of increasing PB and LCBI across more complex atheroma (Ptrend <0.001 for both LCBI and PB). Lesion-based analyses demonstrated the highest LCBI and remodeling index within coronary fibroatheroma (Ptrend <0.001 and 0.02 versus all plaque groups, respectively). Prediction models demonstrated similar abilities of PB, LCBI, and remodeling index for discriminating fibroatheroma (c indices: 0.675, 0.712, and 0.672, respectively). A combined PB+LCBI analysis significantly improved fibroatheroma detection accuracy (c index 0.77, P=0.028 versus PB; net-reclassification index 43%, P=0.003), whereas further adding remodeling index did not (c index 0.80, P=0.27 versus PB+LCBI). In vivo comparisons of 43 age- and sex-matched patients (to the autopsy cohort) undergoing combined NIRS-IVUS coronary imaging yielded similar associations to those demonstrated ex vivo. Adding NIRS to conventional IVUS-derived PB imaging significantly improves the ability to detect more active, potentially vulnerable coronary atheroma. © 2015 American Heart Association, Inc.

  15. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    Energy Technology Data Exchange (ETDEWEB)

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R., E-mail: akennedy@mail.med.upenn.edu

    2014-03-15

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD{sub 50}) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD{sub 50} in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals.

  16. Development of a New Intravascular Low-Profile Device for Exclusion of Aortic Aneurysm: An Experimental Pilot Study

    International Nuclear Information System (INIS)

    Strecker, Ernst-Peter; Haberstroh, Joerg; Boos, Irene; Metz, Stephan; Langer, Mathias; Moliner, Manuel Maynar

    2004-01-01

    Purpose: To present a new intravascular device for the treatment of aorto-iliac aneurysms. Methods: This new device was tested in five dogs with abdominal aortic aneurysm created experimentally by overdilation of a balloon-expandable stent with a 16 or 18 mm wide PTA balloon catheter. The design of the device is based on a self-expanding aortic stent which consists of two stretchable circular frames filled with a textile Dacron mesh membrane that is suspended horizontally into the infrarenal abdominal aorta proximally to the aneurysm. The frames are part of a preshaped double helical structure that is introduced longitudinally through a catheter in a parallel fashion and forming the desired shape at the vessel site to be occluded. Two iliac stent-grafts are introduced in a low-profile status through the membrane sealing the aneurysm sac and holding the stent-grafts in place. After stent-graft expansion, a new bifurcation located more proximally than the natural one is created. The follow-up of the dogs was performed clinically and angiographically, and specimens were evaluated histomorphologically. Results: The membrane device can be introduced through a 9 Fr vascular sheath. Technical success was achieved in four of five dogs. Nine of ten stent-grafts could be fixed securely within the membrane, thus preventing dislocation. Aneurysms were excluded immediately, and blood flow to the external iliac arteries was restored by the stent-grafts. At 6-9 months follow-up of technically successful implanted devices, there were no endoleaks, no migration, no stenoses at contact sites between the implant material and vascular wall, and no stenosis or occlusion of the stent-grafts. At microscopic evaluation, the interspace between the membranes was filled with thrombotic material, thus ensuring exclusion of the aneurysm. Conclusion: This new device was found to be flexible, low profile and useful in excluding abdominal aortic aneurysm in the experimental setting

  17. Comparison of visual versus microscopic methods to detect blood splatter from an intravascular catheter with engineered sharps injury protection.

    Science.gov (United States)

    Ansari, Aiysha; Ramaiah, Padmaja; Collazo, Lillian; Salihu, Hamisu M; Haiduven, Donna

    2013-11-01

    To determine whether retractable intravenous devices produced blood splatter and whether blood splatter frequency differed between visual and microscopy detection methods. In this laboratory-based experiment, 105 venipunctures were performed in a simulated brachial vein containing mock venous blood. The retraction mechanism was activated in a testing chamber with precut fabric filters, placed at 3 different locations, to capture blood splatter. Differences in filter mass, visual inspection, and microscopic analysis for presence of blood on filters were the units of analysis. Descriptive statistics, paired Student t tests, and κ statistics were used for data analysis. Blood splatter was detected visually and microscopically as follows: filter A, 70% and 71%, respectively; filter B, 12% and 9%, respectively; and filter C, 13% and 10%, respectively. A statistically significant difference was observed in the mean mass of filter A between before and after activation when confirmed by the naked eye (P = .014) and microscopically (P = .0092). Substantial agreement between methods was observed for filter A (κ - 0.78 [95% confidence interval, 0.64-0.92]), filter B (κ - 0.73 [95% confidence interval, 0.51-0.95]), and filter C (κ - 0.75 [95% confidence interval, 0.55-0.96]). However, blood was detected by microscopy and not by the naked eye in 7 instances (7%). Our findings demonstrate that splatter, which can potentially expose healthcare workers (HCWs) to bloodborne pathogens, is associated with the activation of intravascular catheters with retraction mechanisms. HCWs may not detect this splatter when it occurs and may not report a splash to mucous membranes or nonintact skin. The need to wear personal protective equipment when using such devices is reinforced.

  18. Risk of developing acute kidney injury associated to contrast media in patients with severe acute pancreatitis, Unidad de Cuidados Intensivos, Hospital Rafael Angel Calderon Guardia, September 2006 to December 2012

    International Nuclear Information System (INIS)

    Nunez Delgado, Karla

    2014-01-01

    The risk of acute kidney injury associated to contrast media is described in patients with severe acute pancreatitis in the Unidad de Cuidados Intensivos of the Hospital Rafael Angel Calderon Guardia of September 2006 to December 2012. The sociodemographic and clinical characteristics of the population studied are identified by data collecting, obtained from clinical records and statistical database of the Intensive Care Unit. The magnitude of the problem is determined by calculating the prevalence of acute kidney injury and possible complications in the study group. Radiologic studies realized by intravascular contrast media were used for diagnostic and therapeutic purposes. The incidence of acute renal injury induced by contrast media has been of the 48.1%, similar to that reported by other authors. Acute kidney injury induced by contrast media is associated with an increase use of health resources, prolonged hospital stay and increased of the hospital mortality. The diagnostic process is described from admission of the patient to hospital [es

  19. Contrast Media: Are There Differences in Nephrotoxicity among Contrast Media?

    Science.gov (United States)

    2014-01-01

    Iodinated contrast agents are usually classified based upon their osmolality—high, low, and isosmolar. Iodinated contrast agents are also nephrotoxic in some but not all patients resulting in loss of glomerular filtration rate. Over the past 30 years, nephrotoxicity has been linked to osmolality although the precise mechanism underlying such a link has been elusive. Improvements in our understanding of the pathogenesis of nephrotoxicity and prospective randomized clinical trials have attempted to further explore the relationship between osmolality and nephrotoxicity. In this review, the basis for our current understanding that there are little if any differences in nephrotoxic potential between low and isosmolar contrast media will be detailed using data from clinical studies. PMID:24587997

  20. Magnetic resonance angiography with blood-pool contrast agents: future applications

    Energy Technology Data Exchange (ETDEWEB)

    Fink, C. [Univ. Hospitals, Grosshadern, Munich (Germany); Goyen, M. [Univ. Medical Center, Hamburg-Eppendorf, Hamburg (Germany); Lotz, J. [Hannover Medical School, Hannover (Germany)

    2007-03-15

    Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

  1. Magnetic resonance angiography with blood-pool contrast agents: future applications

    International Nuclear Information System (INIS)

    Fink, C.; Goyen, M.; Lotz, J.

    2007-01-01

    Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

  2. Pathogenesis of Renal Failure in Multiple Myeloma: Any Role of Contrast Media?

    Directory of Open Access Journals (Sweden)

    Michele Mussap

    2014-01-01

    Full Text Available The spectrum of kidney disease-associated monoclonal immunoglobulin and plasma cell malignancies is remarkably broad and encompasses nearly all nephropathologic entities. Multiple myeloma with kidney impairment at presentation is a medical emergency since the recovery of kidney function is associated with survival benefits. In most cases, kidney impairment may be the first clinical manifestation of malignant plasma cell dyscrasias like multiple myeloma and light chain amyloidosis. Multiple myeloma per se cannot be considered a main risk factor for developing acute kidney injury following intravascular administration of iodinated contrast media. The risk is increased by comorbidities such as chronic kidney disease, diabetes, hypercalcemia, dehydration, and use of nephrotoxic drugs. Before the administration of contrast media, the current recommended laboratory tests for assessing kidney function are serum creatinine measurement and the estimation of glomerular filtration rate by using the CKD-EPI equation. The assessment of Bence Jones proteinuria is unnecessary for evaluating the risk of kidney failure in patients with multiple myeloma, since this test cannot be considered a surrogate biomarker of kidney function.

  3. Pathogenesis of Renal Failure in Multiple Myeloma: Any Role of Contrast Media?

    Science.gov (United States)

    Mussap, Michele; Merlini, Giampaolo

    2014-01-01

    The spectrum of kidney disease-associated monoclonal immunoglobulin and plasma cell malignancies is remarkably broad and encompasses nearly all nephropathologic entities. Multiple myeloma with kidney impairment at presentation is a medical emergency since the recovery of kidney function is associated with survival benefits. In most cases, kidney impairment may be the first clinical manifestation of malignant plasma cell dyscrasias like multiple myeloma and light chain amyloidosis. Multiple myeloma per se cannot be considered a main risk factor for developing acute kidney injury following intravascular administration of iodinated contrast media. The risk is increased by comorbidities such as chronic kidney disease, diabetes, hypercalcemia, dehydration, and use of nephrotoxic drugs. Before the administration of contrast media, the current recommended laboratory tests for assessing kidney function are serum creatinine measurement and the estimation of glomerular filtration rate by using the CKD-EPI equation. The assessment of Bence Jones proteinuria is unnecessary for evaluating the risk of kidney failure in patients with multiple myeloma, since this test cannot be considered a surrogate biomarker of kidney function. PMID:24877060

  4. Porphyrin-containing polyaspartamide gadolinium complexes as potential magnetic resonance imaging contrast agents.

    Science.gov (United States)

    Yan, Guo-Ping; Li, Zhen; Xu, Wei; Zhou, Cheng-Kai; Yang, Lian; Zhang, Qiao; Li, Liang; Liu, Fan; Han, Lin; Ge, Yuan-Xing; Guo, Jun-Fang

    2011-04-04

    Porphyrin-containing polyaspartamide ligands (APTSPP-PHEA-DTPA) were synthesized by the incorporation of diethylenetriaminepentaacetic acid (DTPA) and 5-(4'-aminophenyl)-10,15,20-tris(4'-sulfonatophenyl) porphyrin, trisodium salt (APTSPP) into poly-α,β-[N-(2-hydroxyethyl)-l-aspartamide] (PHEA). These ligands were further reacted with gadolinium chloride to produce macromolecule-gadolinium complexes (APTSPP-PHEA-DTPA-Gd). Experimental data of (1)H NMR, IR, UV and elemental analysis evidenced the formation of the polyaspartamide ligands and gadolinium complexes. In vitro and in vivo property tests indicated that APTSPP-PHEA-DTPA-Gd possessed noticeably higher relaxation effectiveness, less toxicity to HeLa cells, and significantly higher enhanced signal intensities (SI) of the VX2 carcinoma in rabbits with lower injection dose requirement than that of Gd-DTPA. Moreover, APTSPP-PHEA-DTPA-Gd was found to greatly enhance the contrast of MR images of the VX2 carcinoma, providing prolonged intravascular duration, and distinguished the VX2 carcinoma and normal tissues in rabbits according to MR image signal enhancements. These porphyrin-containing polyaspartamide gadolinium complexes can be used as the candidates of contrast agents for targeted MRI to tumors. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  5. Is the inferior vena cava diameter measured by bedside ultrasonography valuable in estimating the intravascular volume in patients with septic shock?

    Directory of Open Access Journals (Sweden)

    Mortaza Talebi Doluie

    2016-07-01

    Full Text Available Introduction:Resuscitation should be initiated immediately in shock. Early goal-directed therapy is an established algorithm for the resuscitation in septic shock. The first step is to maintain cardiac preload. Central venous pressure (CVP plays an important role in goal-directed therapy. Central venous catheterization is invasive and time-consuming in emergency conditions. There are some alternative and noninvasive methods for estimating the intravascular volume such as measuring the inferior vena cava (IVC diameter by ultrasonography. Methods: We searched PubMed, Google scholar, and Scopus databases with keywords (central venous pressure OR venous pressure OR CVP AND (ultrasonography OR sonography AND (sepsis OR septic shock AND (inferior vena cava OR IVC.Result: The search resulted in 2550 articles. The articles were appraised regarding the relevance, type of article, and statistical methods. Finally, 12 articles were selected. The number of patients was between 30 and 83 cases (mean age=57-67 years, intubated and non-intubated in each study. The IVC diameter was measured in respiratory cycle by bedside ultrasonography in longitudinal subxiphoid view and caval index was calculated, then they were compared with the CVP measured by central venous catheter.Discussion: CVP is an indicator of intravascular fluid status and right heart function. CVP measurement is an invasive method and of course with some complications. The IVC is the biggest vein of venous system with low-pressure; expansion of the vein reflects intravascular volume.Conclusion: It seems that IVC diameter measured by ultrasonography could be used as an alternative method for the determination of CVP in the emergency or critical patients.

  6. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography.

    Science.gov (United States)

    Carlier, Stéphane; Didday, Rich; Slots, Tristan; Kayaert, Peter; Sonck, Jeroen; El-Mourad, Mike; Preumont, Nicolas; Schoors, Dany; Van Camp, Guy

    2014-06-01

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator's identification of landmarks to establish the image synchronization. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    International Nuclear Information System (INIS)

    Carlier, Stéphane; Didday, Rich; Slots, Tristan; Kayaert, Peter; Sonck, Jeroen; El-Mourad, Mike; Preumont, Nicolas; Schoors, Dany; Van Camp, Guy

    2014-01-01

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization

  8. Intravascular ultrasound-guided optimized stent deployment. Immediate and 6 months clinical and angiographic results from the Multicenter Ultrasound Stenting in Coronaries Study (MUSIC Study)

    Science.gov (United States)

    de Jaegere, P; Mudra, H; Figulla, H; Almagor, Y; Doucet, S; Penn, I; Colombo, A; Hamm, C; Bartorelli, A; Rothman, M; Nobuyoshi, M; Yamaguchi, T; Voudris, V; DiMario, C; Makovski, S; Hausmann, D; Rowe, S; Rabinovich, S; Sunamura, M; van Es, G A

    1998-08-01

    A study was set up to validate the safety and feasibility of intravascular ultrasound-guided stenting without subsequent anticoagulation, and its impact on the 6 months restenosis rate. The study was designed to be multicentred, prospective, and observational. One hundred and sixty-one patients with stable angina and a de novo coronary artery lesion were enrolled. In four patients, the implantation of a Palmaz-Schatz (with spiral bridge) stent had failed. One of these four patients died 3 days following bypass surgery. In two other patients, intravascular ultrasound assessment was not performed. One hundred and twenty-five of the remaining 155 patients (81%) were treated with aspirin (100 mg x day(-1)), because all three criteria for optimized stent expansion were met. Twenty-two of the remaining 38 patients (25%), in whom at least one criterion was not met were treated with aspirin and acenocoumarol (3 months, INR 2.5-3.5), while 16 patients only received aspirin. Stent thrombosis was documented in two patients (1.3%) for which repeat angioplasty was performed. During the hospital stay, there were no deaths or Q-wave myocardial infarctions. Five patients (3.2%) sustained a non-Q-wave myocardial infarction. During the follow-up period (198+/-38 days, complete for all patients, except one), one patient (0.6%) sustained a Q-wave myocardial infarction, one (0.6%) underwent bypass surgery, and repeat angioplasty was performed in nine patients (5.7%). In two of the nine patients, repeat angioplasty involved another lesion. Therefore, the target lesion revascularization rate during follow-up was 4.5% (seven patients). At quantitative coronary angiography, the minimal lumen diameter (mean+/-SD) increased from 1.12+/-0.34 mm before to 2.89+/-0.35 mm after stenting. Repeat angiography at 6 months was performed in 144 patients (92%). The minimal lumen diameter at follow-up was 2.12+/-0.67 mm. Restenosis (diameter stenosis of 50% or more) was documented in 12 patients or 8

  9. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Carlier, Stéphane, E-mail: sgcarlier@hotmail.com [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Didday, Rich [INDEC Medical Systems Inc., Santa Clara, CA (United States); Slots, Tristan [Pie Medical Imaging BV, Maastricht (Netherlands); Kayaert, Peter; Sonck, Jeroen [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); El-Mourad, Mike; Preumont, Nicolas [Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Schoors, Dany; Van Camp, Guy [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium)

    2014-06-15

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization.

  10. How to misuse echo contrast

    Directory of Open Access Journals (Sweden)

    Missios Anna

    2009-01-01

    Full Text Available Abstract Background Primary intracardiac tumours are rare, there are however several entities that can mimic tumours. Contrast echocardiography has been suggested to aid the differentiation of various suspected masses. We present a case where transthoracic echocardiography completely misdiagnosed a left atrial mass, partly due to use of echo contrast. Case presentation An 80 year-old woman was referred for transthoracic echocardiography because of one-month duration of worsening of dyspnoea. Transthoracic echocardiography displayed a large echodense mass in the left atrium. Intravenous injection of contrast (SonoVue, Bracco Inc., It indicated contrast-enhancement of the structure, suggesting tumour. Transesophageal echocardiography revealed, however, a completely normal finding in the left atrium. Subsequent gastroscopy examination showed a hiatal hernia. Conclusion It is noteworthy that the transthoracic echocardiographic exam completely misdiagnosed what seemed like a left atrial mass, which in part was an effect of the use of echo contrast. This example highlights that liberal use of transoesophageal echocardiography is often warranted if optimal display of cardiac structures is desired.

  11. Life-threatening urethral hemorrhage after placement of a Foley catheter in a patient with uroseptic disseminated intravascular coagulation due to chronic urinary retention induced by untreated benign prostatic hyperplasia.

    Science.gov (United States)

    Ikegami, Yukihiro; Yoshida, Keisuke; Imaizumi, Tsuyoshi; Isosu, Tsuyoshi; Kurosawa, Shin; Murakawa, Masahiro

    2016-10-01

    A 77-year-old man with severe septic disseminated intravascular coagulation following urinary infection was transported to our hospital. He had developed urinary retention induced by untreated prostatic hyperplasia. Immediate drainage with a Foley catheter was successfully carried out, but the hematuria progressed to life-threatening hemorrhage. Complete hemostasis was impossible by surgical treatment because the tissue around the prostatic urethra was very fragile and hemorrhagic. Organized treatments (continuous hemodiafiltration combined with polymyxin-B immobilized fiber column hemoperfusion and systemic treatment with antibiotics and coagulation factors) were commenced soon after the operation. The patient eventually recovered from the septic disseminated intravascular coagulation. This case report illustrates the risk of placement of Foley catheters in patients with severe septic disseminated intravascular coagulation.

  12. Multiscale image contrast amplification (MUSICA)

    Science.gov (United States)

    Vuylsteke, Pieter; Schoeters, Emile P.

    1994-05-01

    This article presents a novel approach to the problem of detail contrast enhancement, based on multiresolution representation of the original image. The image is decomposed into a weighted sum of smooth, localized, 2D basis functions at multiple scales. Each transform coefficient represents the amount of local detail at some specific scale and at a specific position in the image. Detail contrast is enhanced by non-linear amplification of the transform coefficients. An inverse transform is then applied to the modified coefficients. This yields a uniformly contrast- enhanced image without artefacts. The MUSICA-algorithm is being applied routinely to computed radiography images of chest, skull, spine, shoulder, pelvis, extremities, and abdomen examinations, with excellent acceptance. It is useful for a wide range of applications in the medical, graphical, and industrial area.

  13. Contrast enhancement CT by iopamidol

    International Nuclear Information System (INIS)

    Mori, Masaki; Makita, Nobue; Yanai, Kyoko

    1984-01-01

    In order to evaluate the contrast enhancement effect and safety of iopamidol (IOP) in CT examination, IOP was compared with angiographin (AG). In the liver and abdominal aorta, peak CT values were obtained earlier and were higher in the group with AG than in the group with IOP. However, CT values in the group with IOP decreased a little more slowly than those in the group with AG. There was no significant difference in the effect on contrast enhancement between the groups. Intravenous injection of IOP caused lower degree of burning sensation than that of AG, and some of the patients with IOP did not feel burning sensation at all. Changes in clinical laboratory values were slight before and after intravenous injection of IOP. These results suggest that IOP is satisfactory in terms of safety and effect on contrast enhancement in CT examination. (Namekawa, K.)

  14. Contrast-guided image interpolation.

    Science.gov (United States)

    Wei, Zhe; Ma, Kai-Kuang

    2013-11-01

    In this paper a contrast-guided image interpolation method is proposed that incorporates contrast information into the image interpolation process. Given the image under interpolation, four binary contrast-guided decision maps (CDMs) are generated and used to guide the interpolation filtering through two sequential stages: 1) the 45(°) and 135(°) CDMs for interpolating the diagonal pixels and 2) the 0(°) and 90(°) CDMs for interpolating the row and column pixels. After applying edge detection to the input image, the generation of a CDM lies in evaluating those nearby non-edge pixels of each detected edge for re-classifying them possibly as edge pixels. This decision is realized by solving two generalized diffusion equations over the computed directional variation (DV) fields using a derived numerical approach to diffuse or spread the contrast boundaries or edges, respectively. The amount of diffusion or spreading is proportional to the amount of local contrast measured at each detected edge. The diffused DV fields are then thresholded for yielding the binary CDMs, respectively. Therefore, the decision bands with variable widths will be created on each CDM. The two CDMs generated in each stage will be exploited as the guidance maps to conduct the interpolation process: for each declared edge pixel on the CDM, a 1-D directional filtering will be applied to estimate its associated to-be-interpolated pixel along the direction as indicated by the respective CDM; otherwise, a 2-D directionless or isotropic filtering will be used instead to estimate the associated missing pixels for each declared non-edge pixel. Extensive simulation results have clearly shown that the proposed contrast-guided image interpolation is superior to other state-of-the-art edge-guided image interpolation methods. In addition, the computational complexity is relatively low when compared with existing methods; hence, it is fairly attractive for real-time image applications.

  15. Iodinated contrast media nephrotoxicity. Nephrotoxicite des produits de contraste iodes

    Energy Technology Data Exchange (ETDEWEB)

    Meyrier, A. (Hopital Avicenne, 93 - Bobigny (France))

    1994-01-01

    In the late seventies, iodinated contrast agents (ICA) were considered to be a major cause of acute iatrogenic renal failure. Over the last decade new contrast agents have been synthesized, nonionic and less hyperosmolar. The incidence of acute renal failure due to ICAs, varies from 3.7 to 70% of cases according to the series, with an average figure of 10.2%. The pathophysiology of ICA nephrotoxicity was mainly studied in laboratory animal models. Three main factors are involved in an inducing ICA-mediated decrease in glomerular filtration rate: reduction of the renal plasma flow, a direct cytotoxic effect on renal tubular cells and erythrocyte alteration leading to intra-renal sludge. Excluding dysglobulinemias with urinary excretion of immunoglobulin light chains, which represent a special case of maximum nephrotoxicity, 4 main risk factors of renal toxicity have been identified in nondiabetic subjects: previous renal failure with serum creatinine levels greater than 140 [mu]mol per liter, extracellular dehydration, age over 60 and use of high doses of ICA and/or repeated ICA injections before serum creatinine levels return to baseline. Preventive measures for avoiding ICA nephrotoxicity are threefold: maintain or restore adequate hydration with saline infusion, stop NSAID treatment several days before ICA administration, and allow a 5 day interval before repeating contrast media injections. New, nonionic and moderately hyperosmolar contrast agents appear to be much less nephrotoxic than conventional ICAs in laboratory animals and in high-risk patients. It is advisable to select such contrast media for investigating high-risk patients. This approach was recently substantiated in well designed, randomized clinical studies which included more than 2 000 patients. (author).

  16. Quantitative contrast-enhanced mammography for contrast medium kinetics studies

    Science.gov (United States)

    Arvanitis, C. D.; Speller, R.

    2009-10-01

    Quantitative contrast-enhanced mammography, based on a dual-energy approach, aims to extract quantitative and temporal information of the tumour enhancement after administration of iodinated vascular contrast media. Simulations using analytical expressions and optimization of critical parameters essential for the development of quantitative contrast-enhanced mammography are presented. The procedure has been experimentally evaluated using a tissue-equivalent phantom and an amorphous silicon active matrix flat panel imager. The x-ray beams were produced by a tungsten target tube and spectrally shaped using readily available materials. Measurement of iodine projected thickness in mg cm-2 has been performed. The effect of beam hardening does not introduce nonlinearities in the measurement of iodine projected thickness for values of thicknesses found in clinical investigations. However, scattered radiation introduces significant deviations from slope equal to unity when compared with the actual iodine projected thickness. Scatter correction before the analysis of the dual-energy images provides accurate iodine projected thickness measurements. At 10% of the exposure used in clinical mammography, signal-to-noise ratios in excess of 5 were achieved for iodine projected thicknesses less than 3 mg cm-2 within a 4 cm thick phantom. For the extraction of temporal information, a limited number of low-dose images were used with the phantom incorporating a flow of iodinated contrast medium. The results suggest that spatial and temporal information of iodinated contrast media can be used to indirectly measure the tumour microvessel density and determine its uptake and washout from breast tumours. The proposed method can significantly improve tumour detection in dense breasts. Its application to perform in situ x-ray biopsy and assessment of the oncolytic effect of anticancer agents is foreseeable.

  17. Pseudo-extravasation rate constant of dynamic susceptibility contrast-MRI determined from pharmacokinetic first principles.

    Science.gov (United States)

    Li, Xin; Varallyay, Csanad G; Gahramanov, Seymur; Fu, Rongwei; Rooney, William D; Neuwelt, Edward A

    2017-11-01

    Dynamic susceptibility contrast-magnetic resonance imaging (DSC-MRI) is widely used to obtain informative perfusion imaging biomarkers, such as the relative cerebral blood volume (rCBV). The related post-processing software packages for DSC-MRI are available from major MRI instrument manufacturers and third-party vendors. One unique aspect of DSC-MRI with low-molecular-weight gadolinium (Gd)-based contrast reagent (CR) is that CR molecules leak into the interstitium space and therefore confound the DSC signal detected. Several approaches to correct this leakage effect have been proposed throughout the years. Amongst the most popular is the Boxerman-Schmainda-Weisskoff (BSW) K 2 leakage correction approach, in which the K 2 pseudo-first-order rate constant quantifies the leakage. In this work, we propose a new method for the BSW leakage correction approach. Based on the pharmacokinetic interpretation of the data, the commonly adopted R 2 * expression accounting for contributions from both intravascular and extravasating CR components is transformed using a method mathematically similar to Gjedde-Patlak linearization. Then, the leakage rate constant (K L ) can be determined as the slope of the linear portion of a plot of the transformed data. Using the DSC data of high-molecular-weight (~750 kDa), iron-based, intravascular Ferumoxytol (FeO), the pharmacokinetic interpretation of the new paradigm is empirically validated. The primary objective of this work is to empirically demonstrate that a linear portion often exists in the graph of the transformed data. This linear portion provides a clear definition of the Gd CR pseudo-leakage rate constant, which equals the slope derived from the linear segment. A secondary objective is to demonstrate that transformed points from the initial transient period during the CR wash-in often deviate from the linear trend of the linearized graph. The inclusion of these points will have a negative impact on the accuracy of the leakage

  18. Synergistic enhancement of iron oxide nanoparticle and gadolinium for dual-contrast MRI

    International Nuclear Information System (INIS)

    Zhang, Fan; Huang, Xinglu; Qian, Chunqi; Zhu, Lei; Hida, Naoki; Niu, Gang; Chen, Xiaoyuan

    2012-01-01

    Highlights: ► MR contrast agents exert influence on T 1 or T 2 relaxation time of the surrounding tissue. ► Combined use of iron oxide and Gd-DTPA can improve the sensitivity/specificity of lesion detection. ► Dual contrast MRI enhances the delineation of tumor borders and small lesions. ► The effect of DC-MRI can come from the high paramagnetic susceptibility of Gd 3+ . ► The effect of DC-MRI can also come from the distinct pharmacokinetic distribution of SPIO and Gd-DTPA. -- Abstract: Purpose: The use of MR contrast agents allows accurate diagnosis by exerting an influence on the longitudinal (T 1 ) or transverse (T 2 ) relaxation time of the surrounding tissue. In this study, we combined the use of iron oxide (IO) particles and nonspecific extracellular gadolinium chelate (Gd) in order to further improve the sensitivity and specificity of lesion detection. Procedures: With a 7-Tesla scanner, pre-contrasted, IO-enhanced and dual contrast agent enhanced MRIs were performed in phantom, normal animals, and animal models of lymph node tumor metastases and orthotopic brain tumor. For the dual-contrast (DC) MRI, we focused on the evaluation of T 2 weighted DC MRI with IO administered first, then followed by the injection of a bolus of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA). Results: Based on the C/N ratios and MRI relaxometry, the synergistic effect of coordinated administration of Gd-DTPA and IO was observed and confirmed in phantom, normal liver and tumor models. At 30 min after administration of Feridex, Gd-DTPA further decreased T 2 relaxation in liver immediately after the injection. Additional administration of Gd-DTPA also immediately increased the signal contrast between tumor and brain parenchyma and maximized the C/N ratio to −4.12 ± 0.71. Dual contrast MRI also enhanced the delineation of tumor borders and small lesions. Conclusions: DC-MRI will be helpful to improve diagnostic accuracy and decrease the threshold size for

  19. Ultrasound Contrast Agent Microbubble Dynamics

    NARCIS (Netherlands)

    Overvelde, M.L.J.; Vos, Henk; de Jong, N.; Versluis, Michel; Paradossi, Gaio; Pellegretti, Paolo; Trucco, Andrea

    2010-01-01

    Ultrasound contrast agents are traditionally used in ultrasound-assisted organ perfusion imaging. Recently the use of coated microbubbles has been proposed for molecular imaging applications where the bubbles are covered with a layer of targeting ligands to bind specifically to their target cells.

  20. Color contrasting in radioscopy systems

    International Nuclear Information System (INIS)

    Lopaev, V.P.; Pavlov, S.V.; Nazarenko, V.G.

    1979-01-01

    Transformation principles for achromatic radioscopy control systems to color ones have been considered. Described is the developed ''Gamma 1'' roentgen-TV facility with color contrasting, which is based on the principle of analog conversion of brightness signal to a hue. By means of color channels amplifiers realized are the special amplitude characteristics, permitting in comparison with the common method of analogous transformation to obtain the greater number of hues within the identical range of brightnesses of image under investigation due to introducing purple colors. The investigation of amplitude resolution capability of color contrasting device has shown, that in the case of color contrasting of image the amplitude resolution is 1.7-1.8 time higher than in the case of achromatic one. Defectoscopic sensitivity during the testing of 5-20 mm thick steel products in the process of experimental-production tests turned out to be 1.1-1.3 time higher when using color contrasting of radioscopic image. Realization simplicity, high resolution, noise stability and wide functional possibilities of the facility show the prospects for its using during the quality control of welded joints in products of power engineering

  1. Monte Carlo dose characterization of a new 90Sr/90Y source with balloon for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Wang Ruqing; Li, X. Allen; Lobdell, John

    2003-01-01

    Beta emitting source wires or seeds have been adopted in clinical practice of intravascular brachytherapy for coronary vessels. Due to the limitation of penetration depth, this type of source is normally not applicable to treat vessels with large diameter, e.g., peripheral vessel. In the effort to extend application of its beta source for peripheral vessels, Novoste has recently developed a new catheter-based system, the Corona trade mark sign 90 Sr/ 90 Y system. It is a source train of 6 cm length and is jacketed by a balloon. The existence of the balloon increases the penetration of the beta particles and maintains the source within a location away from the vessel wall. Using the EGSnrc Monte Carlo system, we have calculated the two-dimensional (2-D) dose rate distribution of the Corona trade mark sign system in water for a balloon diameter of 5 mm. The dose rates on the transverse axis obtained in this study are in good agreement with calibration results of the National Institute of Standards and Technology for the same system for balloon diameters of 5 and 8 mm. Features of the 2-D dose field were studied in detail. The dose parameters based on AAPM TG-60 protocol were derived. For a balloon diameter of 5 mm, the dose rate at the reference point (defined as r 0 =4.5 mm, 2 mm from the balloon surface) is found to be 0.010 28 Gy min -1 mCi -1 . A new formalism for a better characterization of this long source is presented. Calculations were also performed for other balloon diameters. The dosimetry for this source is compared with a 192 Ir source, commonly used for peripheral arteries. In conclusion, we have performed a detailed dosimetric characterization for a new beta source for peripheral vessels. Our study shows that, from dosimetric point of view, the Corona trade mark sign system can be used for the treatment of an artery with a large diameter, e.g., peripheral vessel

  2. Intravascular ultrasound is a critical tool for accurate endograft sizing in the management of blunt thoracic aortic injury.

    Science.gov (United States)

    Wallace, Gabriel A; Starnes, Benjamin W; Hatsukami, Thomas S; Sobel, Michael; Singh, Niten; Tran, Nam T

    2015-03-01

    Accurate measurement of true aortic luminal diameter (ALD) is critical for endograft sizing in endovascular treatment of blunt thoracic aortic injury (BTAI), but ALD is dynamic and changes with respect to patients' hemodynamic status. This study aimed to characterize how ALD at the time of diagnosis of BTAI compares with ALD at the time of endovascular repair and later at follow-up. This is an Institutional Review Board-approved, single-institution retrospective analysis of prospectively obtained data. Patients were included who presented between July 2007 and December 2012 with computed tomography angiography (CTA)-diagnosed BTAI; who underwent thoracic endovascular aortic repair (TEVAR); and who underwent preoperative CTA, intraoperative intravascular ultrasound (IVUS), and postimplantation CTA. Comparison measurements of the ALD were made among CTA and IVUS images at the level of the left subclavian artery (LSCA) and between initial CTA and postimplantation CTA at 10, 15, and 20 cm distal to the LSCA. Theoretical endograft sizes were determined and compared for each ALD at the LSCA. Twenty-two patients were included in the analysis. Mean age was 38 ± 14 years (range, 17-61 years), with 82% men and mean Injury Severity Score of 43 ± 11 (range, 24-66). Mean time from emergency department admission to initial CTA was -1.2 ± 5 hours (range, -13 to 11.5 hours; negative time implies imaging at an outside facility before admission). Mean time from initial CTA to IVUS was 1.2 ± 1.4 days (range, 2.5 hours-5.7 days) and from IVUS to postimplantation CTA 33 ± 45 days (range, 17 hours-169 days). Overall, ALD measured by IVUS was significantly larger than that by initial CTA (Δ2.5 ± 3.1 mm; P < .05). ALD was also larger at 10, 15, and 20 cm distal to the LSCA in comparing the postimplantation CTA with the initial CTA (Δ2.4, 2.0, and 2.0 mm, respectively; all P < .05). More than half the devices would be sized differently with ALD measured by IVUS at the time of TEVAR

  3. Torsten Almén (1931-2016): the father of non-ionic iodine contrast media.

    Science.gov (United States)

    Nyman, Ulf; Ekberg, Olle; Aspelin, Peter

    2016-09-01

    The Swedish radiologist Torsten Almén is the first clinical radiologist ever to have made a fundamental contribution to intravascular contrast medium design, the development of non-ionic contrast media. He became emotionally triggered by the patients' severe pain each time he injected the ionic "high-osmolar" contrast media when performing peripheral arteriographies in the early 1960s. One day he got a flash of genius that combined the observation of pain, a pathophysiological theory and how to eliminate it with suitable contrast media chemistry. After self-studies in chemistry he developed the concept of iodine contrast media not dissociating into ions in solution to reduce their osmolality and even reach plasma isotonicity. He offered several pharmaceutical companies his concept of mono- and polymeric non-ionic agents but without response, since it was considered against the chemical laws of that time. Contrast media constructed as salts and dissociating into ions in solution was regarded an absolute necessity to achieve high enough water solubility and concentration for diagnostic purposes. Finally a small Norwegian company, Nyegaard & Co., took up his idea 1968 and together they developed the essentially painless "low-osmolar" monomeric non-ionic metrizamide (Amipaque) released in 1974 and iohexol (Omipaque) in 1982 followed by the "iso-osmolar" dimeric non-ionic iodixanol (Visipaque) released in 1993. This has implied a profound paradigm shift with regard to reduction of both hypertonic and chemotoxic side effects, which have been a prerequisite for the today's widespread use of contrast medium-enhanced CT and advanced endovascular interventional techniques even in fragile patients. © The Foundation Acta Radiologica 2016.

  4. Long-term safety and feasibility of three-vessel multimodality intravascular imaging in patients with ST-elevation myocardial infarction

    DEFF Research Database (Denmark)

    Taniwaki, Masanori; Radu, Maria D; Garcia-Garcia, Hector M

    2015-01-01

    We assessed the feasibility and the procedural and long-term safety of intracoronary (i.c) imaging for documentary purposes with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary PCI in the s......We assessed the feasibility and the procedural and long-term safety of intracoronary (i.c) imaging for documentary purposes with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary PCI...... in the setting of IBIS-4 study. IBIS4 (NCT00962416) is a prospective cohort study conducted at five European centers including 103 STEMI patients who underwent serial three-vessel coronary imaging during primary PCI and at 13 months. The feasibility parameter was successful imaging, defined as the number...... of pullbacks suitable for analysis. Safety parameters included the frequency of peri-procedural complications, and major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction (MI) and any clinically-indicated revascularization at 2 years. Clinical outcomes were compared...

  5. In Vitro Capture of Small Ferrous Particles with a Magnetic Filtration Device Designed for Intravascular Use with Intraarterial Chemotherapy: Proof-of-Concept Study.

    Science.gov (United States)

    Mabray, Marc C; Lillaney, Prasheel; Sze, Chia-Hung; Losey, Aaron D; Yang, Jeffrey; Kondapavulur, Sravani; Liu, Derek; Saeed, Maythem; Patel, Anand; Cooke, Daniel; Jun, Young-Wook; El-Sayed, Ivan; Wilson, Mark; Hetts, Steven W

    2016-03-01

    To establish that a magnetic device designed for intravascular use can bind small iron particles in physiologic flow models. Uncoated iron oxide particles 50-100 nm and 1-5 µm in size were tested in a water flow chamber over a period of 10 minutes without a magnet (ie, control) and with large and small prototype magnets. These same particles and 1-µm carboxylic acid-coated iron oxide beads were likewise tested in a serum flow chamber model without a magnet (ie, control) and with the small prototype magnet. Particles were successfully captured from solution. Particle concentrations in solution decreased in all experiments (P particles in water with a large magnet), 97% (50-100-nm particles in water with a small magnet), 99% (1-5-µm particles in water with a large magnet), 99% (1-5-µm particles in water with a small magnet), 95% (50-100-nm particles in serum with a small magnet), 92% (1-5-µm particles in serum with a small magnet), and 75% (1-µm coated beads in serum with a small magnet) lower compared with matched control runs. This study demonstrates the concept of magnetic capture of small iron oxide particles in physiologic flow models by using a small wire-mounted magnetic filter designed for intravascular use. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

  6. Differentiation of early from advanced coronary atherosclerotic lesions: systematic comparison of CT, intravascular US, and optical frequency domain imaging with histopathologic examination in ex vivo human hearts.

    Science.gov (United States)

    Maurovich-Horvat, Pál; Schlett, Christopher L; Alkadhi, Hatem; Nakano, Masataka; Stolzmann, Paul; Vorpahl, Marc; Scheffel, Hans; Tanaka, Atsushi; Warger, William C; Maehara, Akiko; Ma, Shixin; Kriegel, Matthias F; Kaple, Ryan K; Seifarth, Harald; Bamberg, Fabian; Mintz, Gary S; Tearney, Guillermo J; Virmani, Renu; Hoffmann, Udo

    2012-11-01

    To establish an ex vivo experimental setup for imaging coronary atherosclerosis with coronary computed tomographic (CT) angiography, intravascular ultrasonography (US), and optical frequency domain imaging (OFDI) and to investigate their ability to help differentiate early from advanced coronary plaques. All procedures were performed in accordance with local and federal regulations and the Declaration of Helsinki. Approval of the local Ethics Committee was obtained. Overall, 379 histologic cuts from nine coronary arteries from three donor hearts were acquired, coregistered among modalities, and assessed for the presence and composition of atherosclerotic plaque. To assess the discriminatory capacity of the different modalities in the detection of advanced lesions, c statistic analysis was used. Interobserver agreement was assessed with the Cohen κ statistic. Cross sections without plaque at coronary CT angiography and with fibrous plaque at OFDI almost never showed advanced lesions at histopathologic examination (odds ratio [OR]: 0.02 and 0.06, respectively; both Padvanced lesions (OR: 2.49, P=.0003; OR: 2.60, P=.002; and OR: 31.2, Padvanced lesions than intravascular US and coronary CT angiography (area under the receiver operating characteristic curve: 0.858 [95% confidence interval {CI}: 0.802, 0.913], 0.631 [95% CI: 0.554, 0.709], and 0.679 [95% CI: 0.618, 0.740]; respectively, Padvanced coronary plaques. © RSNA, 2012

  7. Deep Learning with Convolutional Neural Network for Differentiation of Liver Masses at Dynamic Contrast-enhanced CT: A Preliminary Study.

    Science.gov (United States)

    Yasaka, Koichiro; Akai, Hiroyuki; Abe, Osamu; Kiryu, Shigeru

    2018-03-01

    Purpose To investigate diagnostic performance by using a deep learning method with a convolutional neural network (CNN) for the differentiation of liver masses at dynamic contrast agent-enhanced computed tomography (CT). Materials and Methods This clinical retrospective study used CT image sets of liver masses over three phases (noncontrast-agent enhanced, arterial, and delayed). Masses were diagnosed according to five categories (category A, classic hepatocellular carcinomas [HCCs]; category B, malignant liver tumors other than classic and early HCCs; category C, indeterminate masses or mass-like lesions [including early HCCs and dysplastic nodules] and rare benign liver masses other than hemangiomas and cysts; category D, hemangiomas; and category E, cysts). Supervised training was performed by using 55 536 image sets obtained in 2013 (from 460 patients, 1068 sets were obtained and they were augmented by a factor of 52 [rotated, parallel-shifted, strongly enlarged, and noise-added images were generated from the original images]). The CNN was composed of six convolutional, three maximum pooling, and three fully connected layers. The CNN was tested with 100 liver mass image sets obtained in 2016 (74 men and 26 women; mean age, 66.4 years ± 10.6 [standard deviation]; mean mass size, 26.9 mm ± 25.9; 21, nine, 35, 20, and 15 liver masses for categories A, B, C, D, and E, respectively). Training and testing were performed five times. Accuracy for categorizing liver masses with CNN model and the area under receiver operating characteristic curve for differentiating categories A-B versus categories C-E were calculated. Results Median accuracy of differential diagnosis of liver masses for test data were 0.84. Median area under the receiver operating characteristic curve for differentiating categories A-B from C-E was 0.92. Conclusion Deep learning with CNN showed high diagnostic performance in differentiation of liver masses at dynamic CT. © RSNA, 2017 Online

  8. Sodium Bicarbonate Versus Sodium Chloride for Preventing Contrast-Associated Acute Kidney Injury in Critically Ill Patients: A Randomized Controlled Trial.

    Science.gov (United States)

    Valette, Xavier; Desmeulles, Isabelle; Savary, Benoit; Masson, Romain; Seguin, Amélie; Sauneuf, Bertrand; Brunet, Jennifer; Verrier, Pierre; Pottier, Véronique; Orabona, Marie; Samba, Désiré; Viquesnel, Gérald; Lermuzeaux, Mathilde; Hazera, Pascal; Dutheil, Jean-Jacques; Hanouz, Jean-Luc; Parienti, Jean-Jacques; du Cheyron, Damien

    2017-04-01

    To test whether hydration with bicarbonate rather than isotonic sodium chloride reduces the risk of contrast-associated acute kidney injury in critically ill patients. Prospective, double-blind, multicenter, randomized controlled study. Three French ICUs. Critically ill patients with stable renal function (n = 307) who received intravascular contrast media. Hydration with 0.9% sodium chloride or 1.4% sodium bicarbonate administered with the same infusion protocol: 3 mL/kg during 1 hour before and 1 mL/kg/hr during 6 hours after contrast medium exposure. The primary endpoint was the development of contrast-associated acute kidney injury, as defined by the Acute Kidney Injury Network criteria, 72 hours after contrast exposure. Patients randomized to the bicarbonate group (n = 151) showed a higher urinary pH at the end of the infusion than patients randomized to the saline group (n = 156) (6.7 ± 2.1 vs 6.2 ± 1.8, respectively; p 0.99) were also similar between the saline and bicarbonate groups, respectively. Except for urinary pH, none of the outcomes differed between the two groups. Among ICU patients with stable renal function, the benefit of using sodium bicarbonate rather than isotonic sodium chloride for preventing contrast-associated acute kidney injury is marginal, if any.

  9. Microbubbles in macrocysts - Contrast-enhanced ultrasound assisted sclerosant therapy of a congenital macrocystic lymphangioma: a case report.

    Science.gov (United States)

    Menendez-Castro, Carlos; Zapke, Maren; Fahlbusch, Fabian; von Goessel, Heiko; Rascher, Wolfgang; Jüngert, Jörg

    2017-07-06

    Congenital cystic lymphangiomas are benign malformations due to a developmental disorder of lymphatic vessels. Besides surgical excision, sclerosant therapy of these lesions by intracavitary injection of OK-432 (Picibanil®), a lyophilized mixture of group A Streptococcus pyogenes, is a common therapeutical option. For an appropriate application of OK-432, a detailed knowledge about the structure and composition of the congenital cystic lymphangioma is essential. SonoVue® is a commercially available contrast agent commonly used in sonography by intravenous and intracavitary application. Here we report the case of 2 month old male patient with a large thoracic congenital cystic lymphangioma. Preinterventional imaging of the malformation was performed by contrast-enhanced ultrasound after intracavitary application of SonoVue® immediately followed by a successful sclerotherapy with OK-432. Contrast agent-enhanced ultrasound imaging offers a valuable option to preinterventionally clarify the anatomic specifications of a congenital cystic lymphangioma in more detail than by single conventional sonography. By the exact knowledge about the composition and especially about the intercystic communications of the lymphangioma sclerosant therapy becomes safer and more efficient.

  10. Ionic versus nonionic contrast media

    International Nuclear Information System (INIS)

    Zylak, C.J.; Gafni, A.

    1988-01-01

    The efficacy and effectiveness of the nonionic contrast media have been established. Widespread usage has been hampered because of the approximate tenfold increase in cost compared with the ionic media. An economic evaluation considering costs and consequences of both interventions (ionic vs nonionic contrast media) was performed; it is a cost effectiveness (CEA) and a cost-benefit analysis (CBA) for the Canadian experience. The results of the CEA demonstrate a value per life-year saved within an acceptable range when compared with value for quality-adjusted life years for programs such as treatment of severe (diastolic≥ 105 mm Hg) and mild (diastolic 95-104 mm Hg) hypertension in men aged 40. The CBA showed a net cost to society when benefits were measured as future treatment costs saved plus productivity gained. However, if people are willing to pay a small amount for the comfort of the new intervention, this will result in a break-even situation

  11. Contrast-enhanced MR angiography

    International Nuclear Information System (INIS)

    Bosmans, H.; Marchal, G.

    1996-01-01

    Despite many optimizations, the current limitations of plain MR angiography include: Saturation that impairs the visualization of veins and arteries with slow flow and spin-dephasing signal voids in locations with turbulent flow. Recently, the use of contrast agents has been proposed to cope with these remaining problems. Because of induced shortening of the T1 of the blood, saturation in the blood vessels is overcome. As a result, arteries and veins are visualized with the same signal intensity, which makes the technique less flow-dependent. In combination with short T1-weighted acquisitions, today CE MRA can be obtained while the patient is holding his breath. This last approach is most promising for abdominal applications since the respiratory motion can be frozen. As these acquisitions also use very short echo times, spin dephasing can be reduced. In conclusion, the use of contrast agents has greatly increased the clinical usefulness of MR angiography. (orig.) [de

  12. Minimum resolvable power contrast model

    Science.gov (United States)

    Qian, Shuai; Wang, Xia; Zhou, Jingjing

    2018-01-01

    Signal-to-noise ratio and MTF are important indexs to evaluate the performance of optical systems. However,whether they are used alone or joint assessment cannot intuitively describe the overall performance of the system. Therefore, an index is proposed to reflect the comprehensive system performance-Minimum Resolvable Radiation Performance Contrast (MRP) model. MRP is an evaluation model without human eyes. It starts from the radiance of the target and the background, transforms the target and background into the equivalent strips,and considers attenuation of the atmosphere, the optical imaging system, and the detector. Combining with the signal-to-noise ratio and the MTF, the Minimum Resolvable Radiation Performance Contrast is obtained. Finally the detection probability model of MRP is given.

  13. Effects of theophyline on contrast

    OpenAIRE

    A.R. Fatahiyan; B. Baqerii; A. Mohseni; A. Makhlouq

    2006-01-01

    Background and purpose: Contrast-induced nephropathy (CN) is one of the most common causes of iatrogenic acute renal failure. In fact CN is the third leading cause of new ARF in hospitalized patients. Radiocontrast-associated ARF is a significant problem in patients with cardiovascular disease. The risk factors for cardiovascular disease also predispose these patients to an increased risk of renal failure. Various strategies have been suggested for preventing CN. Since adenosine may play a ro...

  14. Needleless Intravascular Access

    African Journals Online (AJOL)

    Adele

    times higher needlestick seroconversion rate and no effective available ... Completely “needleless” theatre environments can cause a dramatic escalation in costs. However ... Examples: helicobacter pylori, campylobacter and clostridium. 3.

  15. Contrast detail phantom for SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Cabrejas, M.L. de; Arashiro, J G; Giannone, C. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Camuyrano, M; Nohara, G [Universidad de Buenos Aires, Buenos Aires (Argentina). Facultad Ciencias Exactas

    1996-06-01

    A new low variable contrast phantom for single photon emission computed tomography (SPECT) was constructed, tested and compared with other existing phantoms. It contains simulated cylindrical lesions of four different diameters (D{sub i}), embedded in a cylindrical scattering medium and a uniform section to evaluate tomographic uniformity. The concentration of tracer in the simulated lesions and the scattering medium (background) can be varied to simulate hot and cold lesions. Different applications of the phantom were tested, including determination of the minimum object contrast (OCm) necessary to detect lesions as a function of lesion size, lesion type (hot or cold) and acquisition and processing protocols by visual inspection. This parameter allows categorization of instruments comparing an `image quality index` (IQI). Preliminary comparison with the Britten contrast processing method showed that the detectable OCm was of the same order of magnitude, but the presented device seems more suitable for training and intercomparison purposes. The constructed phantom, of simple design, has proved to be useful for acquisition and processing condition evaluation, OCm estimation and external quality control. (author). 11 refs, 4 figs.

  16. Advancing High Contrast Adaptive Optics

    Science.gov (United States)

    Ammons, M.; Poyneer, L.; GPI Team

    2014-09-01

    A long-standing challenge has been to directly image faint extrasolar planets adjacent to their host suns, which may be ~1-10 million times brighter than the planet. Several extreme AO systems designed for high-contrast observations have been tested at this point, including SPHERE, Magellan AO, PALM-3000, Project 1640, NICI, and the Gemini Planet Imager (GPI, Macintosh et al. 2014). The GPI is the world's most advanced high-contrast adaptive optics system on an 8-meter telescope for detecting and characterizing planets outside of our solar system. GPI will detect a previously unstudied population of young analogs to the giant planets of our solar system and help determine how planetary systems form. GPI employs a 44x44 woofer-tweeter adaptive optics system with a Shack-Hartmann wavefront sensor operating at 1 kHz. The controller uses Fourier-based reconstruction and modal gains optimized from system telemetry (Poyneer et al. 2005, 2007). GPI has an apodized Lyot coronal graph to suppress diffraction and a near-infrared integral field spectrograph for obtaining planetary spectra. This paper discusses current performance limitations and presents the necessary instrumental modifications and sensitivity calculations for scenarios related to high-contrast observations of non-sidereal targets.

  17. Electrofluidic systems for contrast management

    Science.gov (United States)

    Rebello, Keith J.; Maranchi, Jeffrey P.; Tiffany, Jason E.; Brown, Christopher Y.; Maisano, Adam J.; Hagedon, Matthew A.; Heikenfeld, Jason C.

    2012-06-01

    Operating in dynamic lighting conditions and in greatly varying backgrounds is challenging. Current paints and state-ofthe- art passive adaptive coatings (e.g. photochromics) are not suitable for multi- environment situations. A semi-active, low power, skin is needed that can adapt its reflective properties based on the background environment to minimize contrast through the development and incorporation of suitable pigment materials. Electrofluidic skins are a reflective display technology for electronic ink and paper applications. The technology is similar to that in E Ink but makes use of MEMS based microfluidic structures, instead of simple black and white ink microcapsules dispersed in clear oil. Electrofluidic skin's low power operation and fast switching speeds (~20 ms) are an improvement over current state-ofthe- art contrast management technologies. We report on a microfluidic display which utilizes diffuse pigment dispersion inks to change the contrast of the underlying substrate from 5.8% to 100%. Voltage is applied and an electromechanical pressure is used to pull a pigment dispersion based ink from a hydrophobic coated reservoir into a hydrophobic coated surface channel. When no voltage is applied, the Young-Laplace pressure pushes the pigment dispersion ink back down into the reservoir. This allows the pixel to switch from the on and off state by balancing the two pressures. Taking a systems engineering approach from the beginning of development has enabled the technology to be integrated into larger systems.

  18. Dual-energy approach to contrast-enhanced mammography using the balanced filter method: spectral optimization and preliminary phantom measurement.

    Science.gov (United States)

    Saito, Masatoshi

    2007-11-01

    Dual-energy contrast agent-enhanced mammography is a technique of demonstrating breast cancers obscured by a cluttered background resulting from the contrast between soft tissues in the breast. The technique has usually been implemented by exploiting two exposures to different x-ray tube voltages. In this article, another dual-energy approach using the balanced filter method without switching the tube voltages is described. For the spectral optimization of dual-energy mammography using the balanced filters, we applied a theoretical framework reported by Lemacks et al. [Med. Phys. 29, 1739-1751 (2002)] to calculate the signal-to-noise ratio (SNR) in an iodinated contrast agent subtraction image. This permits the selection of beam parameters such as tube voltage and balanced filter material, and the optimization of the latter's thickness with respect to some critical quantity-in this case, mean glandular dose. For an imaging system with a 0.1 mm thick CsI:T1 scintillator, we predict that the optimal tube voltage would be 45 kVp for a tungsten anode using zirconium, iodine, and neodymium balanced filters. A mean glandular dose of 1.0 mGy is required to obtain an SNR of 5 in order to detect 1.0 mg/cm2 iodine in the resulting clutter-free image of a 5 cm thick breast composed of 50% adipose and 50% glandular tissue. In addition to spectral optimization, we carried out phantom measurements to demonstrate the present dual-energy approach for obtaining a clutter-free image, which preferentially shows iodine, of a breast phantom comprising three major components-acrylic spheres, olive oil, and an iodinated contrast agent. The detection of iodine details on the cluttered background originating from the contrast between acrylic spheres and olive oil is analogous to the task of distinguishing contrast agents in a mixture of glandular and adipose tissues.

  19. Dual-energy approach to contrast-enhanced mammography using the balanced filter method: Spectral optimization and preliminary phantom measurement

    International Nuclear Information System (INIS)

    Saito, Masatoshi

    2007-01-01

    Dual-energy contrast agent-enhanced mammography is a technique of demonstrating breast cancers obscured by a cluttered background resulting from the contrast between soft tissues in the breast. The technique has usually been implemented by exploiting two exposures to different x-ray tube voltages. In this article, another dual-energy approach using the balanced filter method without switching the tube voltages is described. For the spectral optimization of dual-energy mammography using the balanced filters, we applied a theoretical framework reported by Lemacks et al. [Med. Phys. 29, 1739-1751 (2002)] to calculate the signal-to-noise ratio (SNR) in an iodinated contrast agent subtraction image. This permits the selection of beam parameters such as tube voltage and balanced filter material, and the optimization of the latter's thickness with respect to some critical quantity--in this case, mean glandular dose. For an imaging system with a 0.1 mm thick CsI:Tl scintillator, we predict that the optimal tube voltage would be 45 kVp for a tungsten anode using zirconium, iodine, and neodymium balanced filters. A mean glandular dose of 1.0 mGy is required to obtain an SNR of 5 in order to detect 1.0 mg/cm 2 iodine in the resulting clutter-free image of a 5 cm thick breast composed of 50% adipose and 50% glandular tissue. In addition to spectral optimization, we carried out phantom measurements to demonstrate the present dual-energy approach for obtaining a clutter-free image, which preferentially shows iodine, of a breast phantom comprising three major components - acrylic spheres, olive oil, and an iodinated contrast agent. The detection of iodine details on the cluttered background originating from the contrast between acrylic spheres and olive oil is analogous to the task of distinguishing contrast agents in a mixture of glandular and adipose tissues

  20. Cervical foraminal steroid injections under CT guidance: retrospective study of in situ contrast aspects in a serial of 248 cases

    Energy Technology Data Exchange (ETDEWEB)

    Pottecher, Pierre; Krause, Denis; Di Marco, Lucy; Loffroy, Romaric; Estivalet, Louis [CHU Dijon Bocage Central, Departement de Radiologie et Imagerie Diagnostique et Interventionnelle, Dijon (France); Duhal, Romain; Demondion, Xavier [CHRU de Lille, Service de Radiologie Musculosquelettique, CCIAL, Laboratoire d' Anatomie, Faculte de Medecine de Lille, Hopital Roger Salengro, Lille (France)

    2015-01-15

    To describe all the CT findings after in situ contrast injection just before steroid injection and to recognize the abnormal aspects associated with intravascular contamination. We retrospectively evaluated 248 cervical transforaminal steroid injections done at the university hospital in Dijon, France, in 2008-2012, to treat cervicobrachial neuralgia inadequately improved by optimal medical treatment for at least 3 weeks. Features describing the opacification patterns were recorded. Five main nonvascular opacification patterns were identified: clumps of contrast agent outside the foramen (16 %), a crab claw pattern surrounding the ganglion (13 %), a ''French'' circumflex accent pattern (15 %), reflux along the needle (7 %), and facet joint capsule opacification (22 %). Concerning the situations requiring a change in needle position, intravenous injection occurred in 26 % of the patients, with a crab claw pattern in half the cases and a clump pattern in half the cases. Intraarteriolar injection was noted in two patients. CT after in situ contrast injection ensures proper needle positioning outside the blood vessels before steroid injection. Penetration of the needle tip into a vein is very common, whereas arteriolar puncture is extremely rare. (orig.)

  1. Are referring clinicians aware of patients at risk from intravenous injection of iodinated contrast media?

    International Nuclear Information System (INIS)

    Konen, Eli; Konen, Osnat; Katz, Miriam; Levy, Yair; Rozenman, Judith; Hertz, Marjorie

    2002-01-01

    AIM: The purpose of our study was to assess the level of awareness of referring clinicians to populations at risk for complications of intravascular administration of iodinated contrast media. SUBJECTS AND METHODS: Two hundred and three physicians from three university hospitals completed an anonymous questionnaire regarding risk factors and contraindications to the intravenous administration of iodinated contrast media. The questionnaire included medical conditions with increased risk for anaphylactoid reaction (asthma, hay fever and food allergy) as well as chemotoxic (ischaemic heart disease, phaeochromocytoma and myasthenia gravis) adverse reactions, some with dependence on renal function (metformin treatment, diabetes mellitus and multiple myeloma). Two additional multiple-choice questions addressed pre-medication protocols and risk of nephrotoxicity in diabetic patients. RESULTS: Asthma, food allergy and hay fever were recognized as risk factors by 81·3%, 77·8% and 61·6% of respondents respectively, while ischaemic heart disease, phaeochromocytoma and myasthenia gravis were defined as such only by 9·8%, 30·0% and 28·6% respectively. Metformin treatment, diabetes mellitus and multiple myeloma, in the presence of normal renal function, were considered as risk factors by 46·3%, 38·9% and 58·1% of respondents respectively. One of the generally accepted pre-medication protocols was selected by 89·8%. The risk of nephrotoxicity in a diabetic patient was correctly assessed by 63·5% of respondents. CONCLUSION: We found a relatively high awareness among referring clinicians of a potential anaphylactoid reaction and nephrotoxicity due to iodinated contrast media. However, additional chemotoxic adverse reactions are less well known. Future efforts to improve communication between clinicians and radiologists should be focused in this direction. Konen, E. et al. (2002)

  2. A case of pulmonary edema developed after intraarterial injection of iodinated contrast medium

    International Nuclear Information System (INIS)

    Min, Byoung Chol; Chun, Kang Woo; Koh, Jae Hyu; Yoon, Jong Sup

    1982-01-01

    Pulmonary edema is a rare adverse reaction to the iodinated contrast medium. Complaining of huge abdominal mass, a 52 years old female was admitted to the Hangang Sungsim Hospital. On physical examination, the patient appeared to be healthy. She had stable vital signs, i.e. BP: 120/80 mmHg, pulse rate: 80/min.etc. An adult head sized mass was palpated in the left mid and lower abdomen. Otherwise nonspecific. On laboratory studies the positive findings were 8-10 WBC/HPF in urine, 25.6 mg/dl for BUN and PVC in EKG. It was negative for urine protein, serum creatinline and liver function test. We injected 100 ml and 30 ml of Urografin 60 through the abdominal aorta dividing 3 times and major branches of the abdominal aorta, respectively. Immediately after complicating angiography, interstitial pulmonary edema was found, showing blurring of the vascular margins, perivascular haziness and thickening of the interlobular septal lines in the both lower lung fields. The blood pressure was dropped to 80/60 mmHg, but pulse rate was normal. She did not complain of dyspnea, and cyanosis was not developed. The urine volume was normally maintained. She was treated for pulmonary edema, which was completely absorbed after 20 hours. And the blood pressure was also normalized. We have experienced a case of pulmonary edema developed after intraarterial injection of the iodinated contrast medium without underlying cardiac, renal and hepatic problems, and reviewed the literatures on mechanisms of pulmonary edema caused by intravascular injection of the iodinated contrast materials

  3. Are referring clinicians aware of patients at risk from intravenous injection of iodinated contrast media?

    Energy Technology Data Exchange (ETDEWEB)

    Konen, Eli; Konen, Osnat; Katz, Miriam; Levy, Yair; Rozenman, Judith; Hertz, Marjorie

    2002-02-01

    AIM: The purpose of our study was to assess the level of awareness of referring clinicians to populations at risk for complications of intravascular administration of iodinated contrast media. SUBJECTS AND METHODS: Two hundred and three physicians from three university hospitals completed an anonymous questionnaire regarding risk factors and contraindications to the intravenous administration of iodinated contrast media. The questionnaire included medical conditions with increased risk for anaphylactoid reaction (asthma, hay fever and food allergy) as well as chemotoxic (ischaemic heart disease, phaeochromocytoma and myasthenia gravis) adverse reactions, some with dependence on renal function (metformin treatment, diabetes mellitus and multiple myeloma). Two additional multiple-choice questions addressed pre-medication protocols and risk of nephrotoxicity in diabetic patients. RESULTS: Asthma, food allergy and hay fever were recognized as risk factors by 81{center_dot}3%, 77{center_dot}8% and 61{center_dot}6% of respondents respectively, while ischaemic heart disease, phaeochromocytoma and myasthenia gravis were defined as such only by 9{center_dot}8%, 30{center_dot}0% and 28{center_dot}6% respectively. Metformin treatment, diabetes mellitus and multiple myeloma, in the presence of normal renal function, were considered as risk factors by 46{center_dot}3%, 38{center_dot}9% and 58{center_dot}1% of respondents respectively. One of the generally accepted pre-medication protocols was selected by 89{center_dot}8%. The risk of nephrotoxicity in a diabetic patient was correctly assessed by 63{center_dot}5% of respondents. CONCLUSION: We found a relatively high awareness among referring clinicians of a potential anaphylactoid reaction and nephrotoxicity due to iodinated contrast media. However, additional chemotoxic adverse reactions are less well known. Future efforts to improve communication between clinicians and radiologists should be focused in this direction. Konen

  4. Influence of high-dose lipid lowering treatment compared to low-dose lipid lowering treatment on plaque composition assessed by intravascular ultrasound virtual histology in patients with ST-segment elevation acute myocardial infarction

    DEFF Research Database (Denmark)

    Egede, Rasmus; Jensen, Lisette Okkels; Hansen, Henrik Steen

    2013-01-01

    Aims: The aim of this study was to evaluate the effect of low-dose versus high-dose rosuvastatin therapy on the necrotic core content in coronary plaques of angiographic non-significant lesions as assessed by intravascular ultrasound - virtual histology. Methods and results: Eighty-seven statin...

  5. Phase contrast STEM for thin samples: Integrated differential phase contrast.

    Science.gov (United States)

    Lazić, Ivan; Bosch, Eric G T; Lazar, Sorin

    2016-01-01

    It has been known since the 1970s that the movement of the center of mass (COM) of a convergent beam electron diffraction (CBED) pattern is linearly related to the (projected) electrical field in the sample. We re-derive a contrast transfer function (CTF) for a scanning transmission electron microscopy (STEM) imaging technique based on this movement from the point of view of image formation and continue by performing a two-dimensional integration on the two images based on the two components of the COM movement. The resulting integrated COM (iCOM) STEM technique yields a scalar image that is linear in the phase shift caused by the sample and therefore also in the local (projected) electrostatic potential field of a thin sample. We confirm that the differential phase contrast (DPC) STEM technique using a segmented detector with 4 quadrants (4Q) yields a good approximation for the COM movement. Performing a two-dimensional integration, just as for the COM, we obtain an integrated DPC (iDPC) image which is approximately linear in the phase of the sample. Beside deriving the CTFs of iCOM and iDPC, we clearly point out the objects of the two corresponding imaging techniques, and highlight the differences to objects corresponding to COM-, DPC-, and (HA) ADF-STEM. The theory is validated with simulations and we present first experimental results of the iDPC-STEM technique showing its capability for imaging both light and heavy elements with atomic resolution and a good signal to noise ratio (SNR). Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Radiographic contrast media, function and future reassessed

    International Nuclear Information System (INIS)

    Sovak, M.

    1988-01-01

    A brief review is given of the use of radiographic contrast media in cholecysto- and cholangiography, central nervous system imaging, urography and angiography. Other aspects briefly discussed are the use of large i.v. doses of contrast media for CT contrast enhancement and the design theory for improved water soluble contrast media. (U.K.)

  7. Use of gadolinium chelate to confirm epidural needle placement in patients with an iodinated contrast reaction

    International Nuclear Information System (INIS)

    Shetty, Sanjay K.; Nelson, Erik N.; Lawrimore, Tara M.; Palmer, William E.

    2007-01-01

    When performing epidural steroid injections for the management of chronic back pain, imaging guidance and a limited epidurogram improve accuracy of needle placement and ensure appropriate delivery of the injectate into the epidural space. We describe our experience using a gadolinium chelate as an alternative contrast agent for limited epidurography in patients with a history of an iodinated contrast reaction. Thirty-eight of 2,067 (1.8%) epidural steroid injections performed in our department over a 25-month period (December 2003-January 2006) employed gadolinium. All injections were performed in the lumbar spine employing a paramedian interlaminar approach. Procedural notes and patient charts were reviewed to evaluate for immediate or delayed complications related to incorrect intrathecal or intravascular needle placement. A retrospective analysis of selected fluoroscopic spot images was performed to evaluate confidence of epidural needle placement; this analysis compared these spot images against those obtained from age- and gender-matched control patients in whom iodinated contrast was used to confirm needle placement. Real-time fluoroscopic guidance permitted confident visualization of an epidurogram at the time of procedure in all 38 cases as documented in the procedural report, and no procedure resulted in a complication due to incorrect needle placement. Retrospective review of fluoroscopic spot images revealed at least moderate confidence of epidural needle placement by both readers in 29/38 cases (76.3%). Fluoroscopic spot images obtained using gadolinium yielded significantly less confidence than images obtained in control patients whose procedures were performed using iodinated contrast (P < 0.01). However, operators were sufficiently confident in needle placement based on real-time fluoroscopic images (not available in our subsequent review) to inject anesthestic in all 38 cases, despite the immediate consequences that could result from intrathecal

  8. Use of gadolinium chelate to confirm epidural needle placement in patients with an iodinated contrast reaction

    Energy Technology Data Exchange (ETDEWEB)

    Shetty, Sanjay K. [Massachusetts General Hospital, Harvard Medical School, Division of Musculoskeletal Radiology, Department of Radiology, Boston, MA (United States); Beth Israel Deaconess Medical Center, Harvard Medical School, Department of Radiology, Boston, MA (United States); Nelson, Erik N.; Lawrimore, Tara M.; Palmer, William E. [Massachusetts General Hospital, Harvard Medical School, Division of Musculoskeletal Radiology, Department of Radiology, Boston, MA (United States)

    2007-04-15

    When performing epidural steroid injections for the management of chronic back pain, imaging guidance and a limited epidurogram improve accuracy of needle placement and ensure appropriate delivery of the injectate into the epidural space. We describe our experience using a gadolinium chelate as an alternative contrast agent for limited epidurography in patients with a history of an iodinated contrast reaction. Thirty-eight of 2,067 (1.8%) epidural steroid injections performed in our department over a 25-month period (December 2003-January 2006) employed gadolinium. All injections were performed in the lumbar spine employing a paramedian interlaminar approach. Procedural notes and patient charts were reviewed to evaluate for immediate or delayed complications related to incorrect intrathecal or intravascular needle placement. A retrospective analysis of selected fluoroscopic spot images was performed to evaluate confidence of epidural needle placement; this analysis compared these spot images against those obtained from age- and gender-matched control patients in whom iodinated contrast was used to confirm needle placement. Real-time fluoroscopic guidance permitted confident visualization of an epidurogram at the time of procedure in all 38 cases as documented in the procedural report, and no procedure resulted in a complication due to incorrect needle placement. Retrospective review of fluoroscopic spot images revealed at least moderate confidence of epidural needle placement by both readers in 29/38 cases (76.3%). Fluoroscopic spot images obtained using gadolinium yielded significantly less confidence than images obtained in control patients whose procedures were performed using iodinated contrast (P < 0.01). However, operators were sufficiently confident in needle placement based on real-time fluoroscopic images (not available in our subsequent review) to inject anesthestic in all 38 cases, despite the immediate consequences that could result from intrathecal

  9. Extra-vascular type of oral intravascular papillary endothelial hyperplasia (Masson′s tumor of lower lip: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    G S Sarode

    2015-01-01

    Full Text Available Intravascular papillary endothelial hyperplasia (IPEH is an unusual reactive lesion of vascular origin, which rarely occurs in the oral cavity. Pathogenetically, is it divided into true, mixed and extra-vascular types. We report a case of extra-vascular IPEH of the lower lip in 54-year-old female patient. Patient gives history of trauma 4 months back with lesion developing at the site to trauma. The lesion was 3 cm × 4 cm in size with soft to firm in consistency. Histologically, it is characterized by an exuberant papillary endothelial cell proliferation toward the lumen of an enlarged blood vessel from the area of an organizing thrombus. The lesion was surgically excised under local anesthesia. The patient was followed for 1-year with no evidence of recurrence. This paper discusses the various aspects of IPEH of the oral cavity such as pathogenesis, clinical features, histopathology treatment, and prognosis.

  10. Intravascular ultrasound and angiographic demonstration of left main stem thrombus-high-risk presentation in a young adult with anabolic steroid abuse.

    Science.gov (United States)

    Garg, Pankaj; Davis, Gershan; Wilson, John Ian; Sivananthan, Mohan

    2010-01-01

    We present a case of acute myocardial infarction in a young adult with a history of anabolic steroid abuse. On diagnostic coronary angiography and intravascular ultrasound, he was found to have a distal left main stem thrombus extending into the proximal left anterior descending artery and a large intermediate vessel. As he was hemodynamically stable and pain-free, he was managed conservatively with triple antiplatelet therapy (aspirin, clopidogrel, and abciximab). This was also to avoid the risk of 'wiring the vessel,' especially if there was underlying dissection. Repeat angiography a few weeks later showed complete thrombus resolution. This is the first reported case of extensive left main stem thrombus in a young patient with anabolic steroid abuse. Management of such cases is not straightforward and our case highlights one approach to both diagnosis and treatment.

  11. Ultrasound contrast agents: an overview.

    Science.gov (United States)

    Cosgrove, David

    2006-12-01

    With the introduction of microbubble contrast agents, diagnostic ultrasound has entered a new era that allows the dynamic detection of tissue flow of both the macro and microvasculature. Underpinning this development is the fact that gases are compressible, and thus the microbubbles expand and contract in the alternating pressure waves of the ultrasound beam, while tissue is almost incompressible. Special software using multiple pulse sequences separates these signals from those of tissue and displays them as an overlay or on a split screen. This can be done at low acoustic pressures (MIdeveloped for myocardial perfusion. In radiology, the most important application is the liver, especially for focal disease. The approach parallels that of dynamic CT or MRI but ultrasound has the advantages of high spatial and temporal resolution. Thus, small lesions that can be indeterminate on CT can often be studied with ultrasound, and situations where the flow is very rapid (e.g., focal nodular hyperplasia where the first few seconds of arterial perfusion may be critical to making the diagnosis) are readily studied. Microbubbles linger in the extensive sinusoidal space of normal liver for several minutes whereas they wash out rapidly from metastases, which have a low vascular volume and thus appear as filling defects. The method has been shown to be as sensitive as three-phase CT. Microbubbles have clinical uses in many other applications where knowledge of the microcirculation is important (the macrocirculation can usually be assessed adequately using conventional Doppler though there are a few important situations where the signal boost given by microbubbles is useful, e.g., transcranial Doppler for evaluating vasospasm after subarachnoid haemorrhage). An important situation where demonstrating tissue devitalisation is important is in interstitial ablation of focal liver lesions: using microbubble contrast agents at the end of a procedure allows immediate evaluation of the

  12. Characteristics of virtual histology-intravascular unltrasound of infarction-related artery atheromatous plaque and pregnancy-associated plasma protein A level: a correlation study

    International Nuclear Information System (INIS)

    Chen Shaobo; Jiang Tiemin; Liang Guoqing; Zhao Jihong; Li Yuming

    2011-01-01

    Objective: To observe the characteristics of virtual histology-intravascular ultrasound (VH-IVUS) in 70 patients with acute ST segment elevated type myocardial infarction (AMI), the findings were compared with that in 70 patients with stable angina (control group), and to analyze the correlation between VH-IVUS characteristics and pregnancy-associated plasma protein A (PAPPA) level. Methods: Seventy patients with ST segment elevated AMI and 70 patients with stable angina, who received percutaneous coronary artery intervention and were encountered from Jan. 2008 to Dec. 2009, were involved in this study. After coronary angiography was completed,the plasma was aspirated from culprit coronary artery with ZEEK catheter. Then, IVUS examination to culprit lesion was carried out and grayscale and VH data were stored. The characteristics of VH-IVUS of culprit atheromatous plaque were observed and its correlation with PAPPA was analyzed. Results: The difference in age,gender, hypertension, smoking, diabetes mellitus and hyperlipidemia between two groups was of no statistical significance, but statistically significant difference in VH-IVUS characteristics of the atheromatous plaque existed between two groups, more fibro-fatty tissue and necrotic tissue with less dense calcium were seen in AMI group. The ratio of necrotic tissue area to calcified tissue area was (3.62±1.46) in AMI group and(7.18±2.53) in control group (P<0.01). PAPPA in AMI group was significantly higher than that in control group (P<0.01). Parameters of VH-IVUS in AMI group were highly correlated with PAPPA (P<0.05 or P<0.01). Conclusion: The characteristics of virtual histology-intravascular ultrasound of infarction-related artery atheromatous plaque include more necrotic tissue, higher ratio of necrotic tissue area to calcified tissue area and a closer correlation with PAPPA. (authors)

  13. Noninvasive in vivo plasma volume and hematocrit in humans: observing long-term baseline behavior to establish homeostasis for intravascular volume and composition

    Science.gov (United States)

    Dent, Paul; Deng, Bin; Goodisman, Jerry; Peterson, Charles M.; Narsipur, Sriram; Chaiken, J.

    2016-04-01

    A new device incorporating a new algorithm and measurement process allows simultaneous noninvasive in vivo monitoring of intravascular plasma volume and red blood cell volume. The purely optical technique involves probing fingertip skin with near infrared laser light and collecting the wavelength shifted light, that is, the inelastic emission (IE) which includes the unresolved Raman and fluorescence, and the un-shifted emission, that is, the elastic emission (EE) which includes both the Rayleigh and Mie scattered light. Our excitation and detection geometry is designed so that from these two simultaneous measurements we can calculate two parameters within the single scattering regime using radiation transfer theory, the intravascular plasma volume fraction and the red blood cell volume fraction. Previously calibrated against a gold standard FDA approved device, 2 hour monitoring sessions on three separate occasions over a three week span for a specific, motionless, and mostly sleeping individual produced 3 records containing a total of 5706 paired measurements of hematocrit and plasma volume. The average over the three runs, relative to the initial plasma volume taken as 100%, of the plasma volume±1σ was 97.56+/-0.55 or 0.56%.For the same three runs, the average relative hematocrit (Hct), referenced to an assumed initial value of 28.35 was 29.37+/-0.12 or stable to +/-0.4%.We observe local deterministic circulation effects apparently associated with the pressure applied by the finger probe as well as longer timescale behavior due to normal ebb and flow of internal fluids due to posture changes and tilt table induced gravity gradients.

  14. Clinical applications of contrast echocardiography

    International Nuclear Information System (INIS)

    Jorge, Leon Galindo

    2005-01-01

    The echocardiography is the technique more used for the diagnosis and pursuit of the cardiovascular illnesses; therefore, their diagnostic precision has acquired a vital importance in the handling of the patients with cardiovascular pathologies. However, with relative frequency, the diagnostic capacity of the echocardiography exam is diminished by limitations of the acoustic window, mainly in-patient with obesity, lung illnesses and alterations of the thoracic wall. This can be obviated with the use of the intra-esophagus echocardiography, although this it is a procedure semi-invasive and not very practical of carrying out in all the patients with problems of acoustic window. In this article the clinical applications are revised more common of the contrast echocardiography

  15. Ultrasound contrast agents: An overview

    International Nuclear Information System (INIS)

    Cosgrove, David

    2006-01-01

    With the introduction of microbubble contrast agents, diagnostic ultrasound has entered a new era that allows the dynamic detection of tissue flow of both the macro and microvasculature. Underpinning this development is the fact that gases are compressible, and thus the microbubbles expand and contract in the alternating pressure waves of the ultrasound beam, while tissue is almost incompressible. Special software using multiple pulse sequences separates these signals from those of tissue and displays them as an overlay or on a split screen. This can be done at low acoustic pressures (MI < 0.3) so that the microbubbles are not destroyed and scanning can continue in real time. The clinical roles of contrast enhanced ultrasound scanning are expanding rapidly. They are established in echocardiography to improve endocardial border detection and are being developed for myocardial perfusion. In radiology, the most important application is the liver, especially for focal disease. The approach parallels that of dynamic CT or MRI but ultrasound has the advantages of high spatial and temporal resolution. Thus, small lesions that can be indeterminate on CT can often be studied with ultrasound, and situations where the flow is very rapid (e.g., focal nodular hyperplasia where the first few seconds of arterial perfusion may be critical to making the diagnosis) are readily studied. Microbubbles linger in the extensive sinusoidal space of normal liver for several minutes whereas they wash out rapidly from metastases, which have a low vascular volume and thus appear as filling defects. The method has been shown to be as sensitive as three-phase CT. Microbubbles have clinical uses in many other applications where knowledge of the microcirculation is important (the macrocirculation can usually be assessed adequately using conventional Doppler though there are a few important situations where the signal boost given by microbubbles is useful, e.g., transcranial Doppler for evaluating

  16. Phase contrast STEM for thin samples: Integrated differential phase contrast

    International Nuclear Information System (INIS)

    Lazić, Ivan; Bosch, Eric G.T.; Lazar, Sorin

    2016-01-01

    It has been known since the 1970s that the movement of the center of mass (COM) of a convergent beam electron diffraction (CBED) pattern is linearly related to the (projected) electrical field in the sample. We re-derive a contrast transfer function (CTF) for a scanning transmission electron microscopy (STEM) imaging technique based on this movement from the point of view of image formation and continue by performing a two-dimensional integration on the two images based on the two components of the COM movement. The resulting integrated COM (iCOM) STEM technique yields a scalar image that is linear in the phase shift caused by the sample and therefore also in the local (projected) electrostatic potential field of a thin sample. We confirm that the differential phase contrast (DPC) STEM technique using a segmented detector with 4 quadrants (4Q) yields a good approximation for the COM movement. Performing a two-dimensional integration, just as for the COM, we obtain an integrated DPC (iDPC) image which is approximately linear in the phase of the sample. Beside deriving the CTFs of iCOM and iDPC, we clearly point out the objects of the two corresponding imaging techniques, and highlight the differences to objects corresponding to COM-, DPC-, and (HA) ADF-STEM. The theory is validated with simulations and we present first experimental results of the iDPC-STEM technique showing its capability for imaging both light and heavy elements with atomic resolution and a good signal to noise ratio (SNR). - Highlights: • First DPC-based atomic resolution images of potential and charge density are obtained. • This is enabled by integration and differentiation of 2D DPC signals, respectively. • Integrated DPC (iDPC) based on 4 quadrant imaging is compared to iCOM imaging. • Noise analysis and comparison with standard STEM imaging modes is provided. • iDPC allows direct imaging of light (C, N, O …) and heavy (Ga, Au …) atoms together.

  17. Phase contrast STEM for thin samples: Integrated differential phase contrast

    Energy Technology Data Exchange (ETDEWEB)

    Lazić, Ivan, E-mail: ivan.lazic@fei.com; Bosch, Eric G.T.; Lazar, Sorin

    2016-01-15

    It has been known since the 1970s that the movement of the center of mass (COM) of a convergent beam electron diffraction (CBED) pattern is linearly related to the (projected) electrical field in the sample. We re-derive a contrast transfer function (CTF) for a scanning transmission electron microscopy (STEM) imaging technique based on this movement from the point of view of image formation and continue by performing a two-dimensional integration on the two images based on the two components of the COM movement. The resulting integrated COM (iCOM) STEM technique yields a scalar image that is linear in the phase shift caused by the sample and therefore also in the local (projected) electrostatic potential field of a thin sample. We confirm that the differential phase contrast (DPC) STEM technique using a segmented detector with 4 quadrants (4Q) yields a good approximation for the COM movement. Performing a two-dimensional integration, just as for the COM, we obtain an integrated DPC (iDPC) image which is approximately linear in the phase of the sample. Beside deriving the CTFs of iCOM and iDPC, we clearly point out the objects of the two corresponding imaging techniques, and highlight the differences to objects corresponding to COM-, DPC-, and (HA) ADF-STEM. The theory is validated with simulations and we present first experimental results of the iDPC-STEM technique showing its capability for imaging both light and heavy elements with atomic resolution and a good signal to noise ratio (SNR). - Highlights: • First DPC-based atomic resolution images of potential and charge density are obtained. • This is enabled by integration and differentiation of 2D DPC signals, respectively. • Integrated DPC (iDPC) based on 4 quadrant imaging is compared to iCOM imaging. • Noise analysis and comparison with standard STEM imaging modes is provided. • iDPC allows direct imaging of light (C, N, O …) and heavy (Ga, Au …) atoms together.

  18. The fluoro-less and contrast-less peripheral endovascular intervention: a concept for the future today

    International Nuclear Information System (INIS)

    Ephrem, Georges; Lau, Joe F.; Meraj, Perwaiz M.

    2015-01-01

    Introduction: Percutaneous endovascular revascularization requires fluoroscopic guidance and radiopaque contrast use. This approach becomes problematic, especially in patients with advanced renal disease or allergies to iodinated contrast medium. The direct (exposure) and indirect (lead garment) burden of radiation affects patients and operators alike. Purpose: We propose a completely contrast-free, fluoroscopy-free approach to endovascular diagnostic arterial imaging and percutaneous intervention using available technologies, and outline a timeframe for its implementation. Project Description/Methodology: Ultrasound imaging of the leg creates a roadmap of the vessel and identifies the lesion of interest. Device-based sensors using a low-powered electromagnetic field allow for wiring of the vessel. This is followed by the use of intravascular ultrasonography and near infrared spectroscopy to characterize the lesion dimensions and composition. After completion of the diagnostic phase of the process, the interventional portion with deployment of an angioplasty balloon and/or stent is performed using the electromagnetic field-guided sensors. Feasibility: The project uses already available technologies. Benefits/Anticipated Outcomes: This project demonstrates the real potential of performing endovascular peripheral intervention without fluoroscopy or contrast in a practical, user-friendly way with the currently available technology. The prospects in renal function preservation and radiation avoidance for both patients and operators are extremely attractive. - Highlights: • We propose an endovascular peripheral intervention without fluoroscopy or contrast. • It is based on ultrasound, electromagnetic sensors, and near infrared spectroscopy. • The method is practical and uses available technology. • The prospects in renal function preservation and radiation avoidance are excellent

  19. The fluoro-less and contrast-less peripheral endovascular intervention: a concept for the future today

    Energy Technology Data Exchange (ETDEWEB)

    Ephrem, Georges, E-mail: g.ephrem@gmail.com; Lau, Joe F.; Meraj, Perwaiz M.

    2015-07-15

    Introduction: Percutaneous endovascular revascularization requires fluoroscopic guidance and radiopaque contrast use. This approach becomes problematic, especially in patients with advanced renal disease or allergies to iodinated contrast medium. The direct (exposure) and indirect (lead garment) burden of radiation affects patients and operators alike. Purpose: We propose a completely contrast-free, fluoroscopy-free approach to endovascular diagnostic arterial imaging and percutaneous intervention using available technologies, and outline a timeframe for its implementation. Project Description/Methodology: Ultrasound imaging of the leg creates a roadmap of the vessel and identifies the lesion of interest. Device-based sensors using a low-powered electromagnetic field allow for wiring of the vessel. This is followed by the use of intravascular ultrasonography and near infrared spectroscopy to characterize the lesion dimensions and composition. After completion of the diagnostic phase of the process, the interventional portion with deployment of an angioplasty balloon and/or stent is performed using the electromagnetic field-guided sensors. Feasibility: The project uses already available technologies. Benefits/Anticipated Outcomes: This project demonstrates the real potential of performing endovascular peripheral intervention without fluoroscopy or contrast in a practical, user-friendly way with the currently available technology. The prospects in renal function preservation and radiation avoidance for both patients and operators are extremely attractive. - Highlights: • We propose an endovascular peripheral intervention without fluoroscopy or contrast. • It is based on ultrasound, electromagnetic sensors, and near infrared spectroscopy. • The method is practical and uses available technology. • The prospects in renal function preservation and radiation avoidance are excellent.

  20. Informed consent in contrast-enhanced CT. Understanding of risks and identification of possible prognostic factors; Patientenaufklaerung bei kontrastmittelgestuetzter CT. Risikoverstaendnis und Identifikation moeglicher Prognosefaktoren

    Energy Technology Data Exchange (ETDEWEB)

    Roehrl, S.; Dendl, L.M.; Scharf, G.; Stroszczynski, C.; Schreyer, A.G. [University Medical Center Regensburg (Germany). Dept. of Radiology; Zeman, F. [University Medical Center Regensburg (Germany). Center for Clinical Studies

    2015-11-15

    Aim of our study was to assess understanding of risks associated with intravascular application of contrast media in patients undergoing CT examination. We wanted to evaluate epidemiologic and socio-economic prognostic factors for a higher understanding of risks. Additionally, we evaluated a possible correlation between an extensive, outcome-oriented oral informed consent and better understanding of risks. 120 patients distributed in 2 study arms participated in this prospective study. In study arm I, the treating physician was not informed that his patients participated in a study whereas the physician in study arm II knew about the survey. After the informed consent we performed a standardized, semi-structured interview to enquire the 3 most frequent risks of intravascular application of contrast agents (anaphylactoid reactions, nephropathy and thyrotoxic crisis) and epidemiologic data. The understanding of the risks was evaluated using a 6 point scale. Patients scored 3.73 points in study arm I and 4.93 points in arm II on average. The statistical difference between both study arms was highly significant (p < 0.001). In a combined logistic regression analysis, only ''higher education'' (p = 0.001) and participation in study arm II (p =0.001) showed a significant connection to a better understanding of risks. Patients profit from an outcome-oriented and individualized informed consent. Due to the significant correlation between educational level and understanding of risks, informed consent should be adjusted to the educational status of the individual patient, e.g. by using didactic aids or individualized information sheets.

  1. Evaluation of contrast in duplicated radiographs

    International Nuclear Information System (INIS)

    Thunthy, K.H.; Weinberg, R.

    1982-01-01

    This investigation evaluated changes in the contrast of duplicated radiographs made at different ultraviolet light exposures. Increasing ultraviolet light exposure had different effects on the duplicates of originals of different background densities. When correctly exposed, a duplicate radiograph enhanced contrast. When originals had the same contrast but different background densities, their duplicates did not have the same contrast. It was not possible to duplicate accurately all the different contrasts measured on an original. It was possible, however, to produce duplicates with all contrasts greater than those of the original

  2. Fluorine cardiovascular magnetic resonance angiography in vivo at 1.5 T with perfluorocarbon nanoparticle contrast agents.

    Science.gov (United States)

    Neubauer, Anne M; Caruthers, Shelton D; Hockett, Franklin D; Cyrus, Tillman; Robertson, J David; Allen, J Stacy; Williams, Todd D; Fuhrhop, Ralph W; Lanza, Gregory M; Wickline, Samuel A

    2007-01-01

    While the current gold standard for coronary imaging is X-ray angiography, evidence is accumulating that it may not be the most sensitive technique for detecting unstable plaque. Other imaging modalities, such as cardiovascular magnetic resonance (CMR), can be used for plaque characterization, but suffer from long scan and reconstruction times for determining regions of stenosis. We have developed an intravascular fluorinated contrast agent that can be used for angiography with cardiovascular magnetic resosnace at clinical field strengths (1.5 T). This liquid perfluorocarbon nanoparticle contains a high concentration of fluorine atoms that can be used to generate contrast on 19F MR images without any competing background signal from surrounding tissues. By using a perfluorocarbon with 20 equivalent fluorine molecules, custom-built RF coils, a modified clinical scanner, and an efficient steady-state free procession sequence, we demonstrate the use of this agent for angiography of small vessels in vitro, ex vivo, and in vivo. The surprisingly high signal generated with very short scan times and low doses of perfluorocarbon indicates that this technique may be useful in clinical settings when coupled with advanced imaging strategies.

  3. Binocular contrast discrimination needs monocular multiplicative noise

    Science.gov (United States)

    Ding, Jian; Levi, Dennis M.

    2016-01-01

    The effects of signal and noise on contrast discrimination are difficult to separate because of a singularity in the signal-detection-theory model of two-alternative forced-choice contrast discrimination (Katkov, Tsodyks, & Sagi, 2006). In this article, we show that it is possible to eliminate the singularity by combining that model with a binocular combination model to fit monocular, dichoptic, and binocular contrast discrimination. We performed three experiments using identical stimuli to measure the perceived phase, perceived contrast, and contrast discrimination of a cyclopean sine wave. In the absence of a fixation point, we found a binocular advantage in contrast discrimination both at low contrasts (discrimination mechanisms: a nonlinear contrast transducer and multiplicative noise (MN). A binocular combination model (the DSKL model; Ding, Klein, & Levi, 2013b) was first fitted to both the perceived-phase and the perceived-contrast data sets, then combined with either the nonlinear contrast transducer or the MN mechanism to fit the contrast-discrimination data. We found that the best model combined the DSKL model with early MN. Model simulations showed that, after going through interocular suppression, the uncorrelated noise in the two eyes became anticorrelated, resulting in less binocular noise and therefore a binocular advantage in the discrimination task. Combining a nonlinear contrast transducer or MN with a binocular combination model (DSKL) provides a powerful method for evaluating the two putative contrast-discrimination mechanisms. PMID:26982370

  4. Brute force absorption contrast microtomography

    Science.gov (United States)

    Davis, Graham R.; Mills, David

    2014-09-01

    In laboratory X-ray microtomography (XMT) systems, the signal-to-noise ratio (SNR) is typically determined by the X-ray exposure due to the low flux associated with microfocus X-ray tubes. As the exposure time is increased, the SNR improves up to a point where other sources of variability dominate, such as differences in the sensitivities of adjacent X-ray detector elements. Linear time-delay integration (TDI) readout averages out detector sensitivities on the critical horizontal direction and equiangular TDI also averages out the X-ray field. This allows the SNR to be increased further with increasing exposure. This has been used in dentistry to great effect, allowing subtle variations in dentine mineralisation to be visualised in 3 dimensions. It has also been used to detect ink in ancient parchments that are too damaged to physically unroll. If sufficient contrast between the ink and parchment exists, it is possible to virtually unroll the tomographic image of the scroll in order that the text can be read. Following on from this work, a feasibility test was carried out to determine if it might be possible to recover images from decaying film reels. A successful attempt was made to re-create a short film sequence from a rolled length of 16mm film using XMT. However, the "brute force" method of scaling this up to allow an entire film reel to be imaged presents a significant challenge.

  5. Integral equations with contrasting kernels

    Directory of Open Access Journals (Sweden)

    Theodore Burton

    2008-01-01

    Full Text Available In this paper we study integral equations of the form $x(t=a(t-\\int^t_0 C(t,sx(sds$ with sharply contrasting kernels typified by $C^*(t,s=\\ln (e+(t-s$ and $D^*(t,s=[1+(t-s]^{-1}$. The kernel assigns a weight to $x(s$ and these kernels have exactly opposite effects of weighting. Each type is well represented in the literature. Our first project is to show that for $a\\in L^2[0,\\infty$, then solutions are largely indistinguishable regardless of which kernel is used. This is a surprise and it leads us to study the essential differences. In fact, those differences become large as the magnitude of $a(t$ increases. The form of the kernel alone projects necessary conditions concerning the magnitude of $a(t$ which could result in bounded solutions. Thus, the next project is to determine how close we can come to proving that the necessary conditions are also sufficient. The third project is to show that solutions will be bounded for given conditions on $C$ regardless of whether $a$ is chosen large or small; this is important in real-world problems since we would like to have $a(t$ as the sum of a bounded, but badly behaved function, and a large well behaved function.

  6. Contrast enhanced CT of spinal cord angioma

    International Nuclear Information System (INIS)

    Nakamura, Takahiko; Ebitani, Tsutomu; Honma, Takao; Sofue, Muroto; Nakamura, Shigeru

    1982-01-01

    Contrast enhanced CT on 6 patients with spinal cord angioma showed enhancement in 2 of them. The conditions to produce contrast enhancement were the window width of 100 - 200, and the window level of 0 - 50. In spinal cord angioma, contrast enhanced CT is presently only an adjunct to angiography and myelography. Nevertheless, contrast enhanced CT is useful in the screening test for spinal cord angioma, in the patients who are nonindicated to angiography, and in the postoperative follow-up. (Ueda, J.)

  7. Using Contrastive Rhetoric in the ESL Classroom

    Science.gov (United States)

    Quinn, Janet M.

    2012-01-01

    Contrastive rhetoric studies the writing of second language learners to understand how it is affected by their first language and culture. The field of contrastive rhetoric is as multidimensional as second language writing is complex. It draws on the work of contrastive analysis, anthropology, linguistics, pedagogy, culture studies, translation…

  8. Contrast media are helpful in computerized tomography

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Contrast media very often can decisively improve the image contrasts, and thus contribute to making the differential diagnosis more specific. This survey of a symposium on the current status of CT refers particularly to the lectures that discussed the use of contrast media for neuroradiology, and the risks involved. (orig.) [de

  9. Aspectos técnicos da ressonância magnética de mama com meio de contraste: revisão da literatura Technical aspects of contrast-enhanced magnetic resonance imaging of the breast: literature review

    Directory of Open Access Journals (Sweden)

    Denise de Deus Leopoldino

    2005-08-01

    Full Text Available Com a difusão do uso de meios de contraste, avanços na tecnologia das bobinas de superfície e desenvolvimento de protocolos rápidos de aquisição de imagens, a ressonância magnética (RM de mama com meio de contraste tem-se mostrado importante modalidade na detecção, diagnóstico e estadiamento do câncer de mama. Apesar desses avanços, existem alguns pontos não consensuais no que diz respeito aos aspectos técnicos e critérios de interpretação de imagem da RM contrastada de mama. Neste artigo fazemos revisão bibliográfica dos parâmetros de interpretação de imagens e aspectos técnicos da RM de mama, incluindo considerações sobre a "performance" do equipamento, bobinas de radiofreqüência dedicadas, modo de utilização de contraste paramagnético, técnicas de supressão de gordura, planos de aquisição, seqüências de pulso e fontes de artefato.With the advances in surface coil technology and the development of new imaging protocols in addition to the increase of the use of contrast agents, contrast enhanced magnetic resonance imaging (MRI has emerged as a promising modality for detection, diagnosis and staging of breast cancer. Despite these advances, there are some unresolved issues, including no defined standard technique for contrast-enhanced breast MRI and no standard criteria of interpretation for the evaluation of such studies. In this article, we review the literature and discuss the general requirements and recommendations for contrast agent-enhanced breast MRI, including image interpretation criteria, MR equipment, dedicated radiofrequency coils, use of paramagnetic contrast agents, fat-suppression techniques, planes of acquisition, pulse sequence specifications and artifact sources.

  10. Effect of intensifying screens to subject contrast

    International Nuclear Information System (INIS)

    Lee, In Ja; Huh, Joon; Kang, Hong Seok; Yoon, Chul Ho

    1990-01-01

    It is an experimental report about object contrast according to the Kinds of screen and obtained results as follows ; 1. In the same object radiography, use acquired the difference of the object contrast between LT-II(CaWO 4 system) and G4(Gd system) screens. 2. object contrast more decreased in Gd system screen than CaWO 4 and object contrast controlled by X-ray tube voltage. 3. The difference of object contrast seen clearly in 80 kVp

  11. Contrast Enhanced US in the Abdomen

    International Nuclear Information System (INIS)

    Chung, Yong Eun; Kim, Ki Whang

    2012-01-01

    Contrast enhanced ultrasound, which was introduced in 1996, has been widely used in Europe and Eastern Asia. Ultrasound contrast agent can be classified as first generation and second generation, depending on the gas within the microbubble. With the first generation contrast agent, the high MI technique was used, and only intermittent scanning was possible due to destruction of the microbubble during scanning. Use of the second generation contrast agent with the low MI technique makes continuous scanning possible. Contrast enhanced US can be used in detection and differentiation of focal liver lesions. It is also helpful for monitoring of radiofrequency ablation and for targeting of US guided biopsy. Currently, because morphologic criteria alone may not reflect the response of the tumor to treatment, new criteria are needed for treatment evaluation after administration of anti-angiogenic agents. Contrast enhanced US could provide quantitative markers for evaluation of the response to treatment via use of dynamic contrast enhanced US. Due to cost-effectiveness, contrast enhanced US is not yet widely used in Korea; however, considering recent issues regarding contrast agent related adverse reaction, such as contrast induced nephropathy and nephrogenic systemic fibrosis, and radiation exposure, contrast enhanced US might be more widely used in Korea, as an alternative imaging modality in the future.

  12. MRI and CT contrast media extravasation

    Science.gov (United States)

    Heshmatzadeh Behzadi, Ashkan; Farooq, Zerwa; Newhouse, Jeffery H.; Prince, Martin R.

    2018-01-01

    Abstract Background: This systematic review combines data from multiple papers on contrast media extravasation to identify factors contributing to increased extravasation risk. Methods: Data were extracted from 17 papers reporting 2191 extravasations in 1,104,872 patients (0.2%) undergoing computed tomography (CT) or magnetic resonance imaging (MRI). Results: Extravasation rates were 0.045% for gadolinium-based contrast agents (GBCA) and nearly 6-fold higher, 0.26% for iodinated contrast agents. Factors associated with increased contrast media extravasations included: older age, female gender, using an existing intravenous (IV) instead of placing a new IV in radiology, in-patient status, use of automated power injection, high injection rates, catheter location, and failing to warm up the more viscous contrast media to body temperature. Conclusion: Contrast media extravasation is infrequent but nearly 6 times less frequent with GBCA for MRI compared with iodinated contrast used in CT. PMID:29489663

  13. Late lumen loss and intima hyperplasia after sirolimus-eluting and zotarolimus-eluting stent implantation in diabetic patients: the diabetes and drug-eluting stent (DiabeDES III) angiography and intravascular ultrasound trial

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Mæng, Michael; Thayssen, Per

    2011-01-01

    Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to neointimal hyperplasia (NIH). The aim of this study was to use quantitative coronary angiography (QCA) and volumetric intravascular ultrasound (IVUS) to evaluate the effects...... of the sirolimus-eluting Cypher® stent (SES) and the zotarolimus-eluting Endeavor® stent (ZES) on angiographic late lumen loss and intima hyperplasia in diabetic patients....

  14. Antiatherosclerotic effects of long-term maximally intensive statin therapy after acute coronary syndrome: insights from Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin.

    Science.gov (United States)

    Puri, Rishi; Nissen, Steven E; Shao, Mingyuan; Ballantyne, Christie M; Barter, Philip J; Chapman, M John; Erbel, Raimund; Libby, Peter; Raichlen, Joel S; Uno, Kiyoko; Kataoka, Yu; Nicholls, Stephen J

    2014-11-01

    Patients with acute coronary syndromes (ACS) display diffuse coronary atheroma instability and heightened risk of early and late recurrent coronary events. We compared the long-term antiatherosclerotic efficacy of high-intensity statins in patients with ACS when compared with stable disease. Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The overall effect of high-intensity statins on the change in coronary percent atheroma volume and major adverse cardiovascular events (death/nonfatal myocardial infarction/coronary revascularization) were evaluated in this post hoc analysis. When compared with non-ACS patients (n=678), patients with ACS (n=361) were younger, actively smoking, and have had a previous myocardial infarction (all P<0.001). At baseline, patients with ACS exhibited lower high-density lipoprotein cholesterol (43.5±11 versus 45.8±11 mg/dL; P=0.002), a higher apolipoprotein B: apolipoprotein A-1 ratio (0.90±0.24 versus 0.83±0.24; P<0.001) and greater percent atheroma volume (37.3±8.5% versus 35.9±8.1%; P=0.01) when compared with non-ACS patients. Despite similar achieved levels of lipid and inflammatory markers after high-intensity statin therapy, patients with ACS demonstrated greater percent atheroma volume regression than non-ACS patients (-1.46±0.14 versus -0.89±0.13; P=0.003). After propensity-weighted multivariable adjustment, baseline percent atheroma volume (P<0.001) and an ACS clinical presentation (P=0.02) independently associated with plaque regression. The 24-month major adverse cardiovascular events-free survival was similar between patients with ACS and non-ACS (90.6 versus 92.9%; P=0.25). Long-term high-intensity statin therapy caused greater plaque regression and comparable major adverse cardiovascular events rates in

  15. Flash Infrared Thermography Contrast Data Analysis Technique

    Science.gov (United States)

    Koshti, Ajay

    2014-01-01

    This paper provides information on an IR Contrast technique that involves extracting normalized contrast versus time evolutions from the flash thermography inspection infrared video data. The analysis calculates thermal measurement features from the contrast evolution. In addition, simulation of the contrast evolution is achieved through calibration on measured contrast evolutions from many flat-bottom holes in the subject material. The measurement features and the contrast simulation are used to evaluate flash thermography data in order to characterize delamination-like anomalies. The thermal measurement features relate to the anomaly characteristics. The contrast evolution simulation is matched to the measured contrast evolution over an anomaly to provide an assessment of the anomaly depth and width which correspond to the depth and diameter of the equivalent flat-bottom hole (EFBH) similar to that used as input to the simulation. A similar analysis, in terms of diameter and depth of an equivalent uniform gap (EUG) providing a best match with the measured contrast evolution, is also provided. An edge detection technique called the half-max is used to measure width and length of the anomaly. Results of the half-max width and the EFBH/EUG diameter are compared to evaluate the anomaly. The information provided here is geared towards explaining the IR Contrast technique. Results from a limited amount of validation data on reinforced carbon-carbon (RCC) hardware are included in this paper.

  16. Mesoporous silicon particles as intravascular drug delivery vectors: fabrication, in-vitro, and in-vivo assessments

    International Nuclear Information System (INIS)

    Chiappini, Ciro; Tasciotti, Ennio; Serda, Rita E.; Brousseau, Lou; Liu, Xuewu; Ferrari, M.

    2011-01-01

    Porous silicon is an attractive biomaterial for drug delivery thanks to its biocompatibility, biodegradability, ease of fabrication, tunable nanostructure, and porous network. Herein we briefly present the development of a multi-stage delivery vector that leverages these advantages to enhance delivery of systemically administered therapeutic agents. We illustrate the rational design, objective-oriented fabrication and geometric control of first stage porous silicon microparticles. We describe how geometry affects the biodistribution of first stage vectors and how their porous structure affects the loading and release of second stage theranostic payloads. We describe the mechanism of cellular internalization and intracellular trafficking of particles. Finally we present two multi-stage vector prototypes for the delivery of magnetic resonance imaging contrast agents and small interfering RNA (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. Mesoporous silicon particles as intravascular drug delivery vectors: fabrication, in-vitro, and in-vivo assessments

    Energy Technology Data Exchange (ETDEWEB)

    Chiappini, Ciro [Department of Biomedical Engineering, University of Texas at Austin, 1 University Station, Austin, TX, 78712 (United States); Tasciotti, Ennio; Serda, Rita E.; Brousseau, Lou; Liu, Xuewu [Department of Nanomedicine and Biomedical Engineering, Mehtodist Hospital Research Institute, 6565 Fannin Street, Houston, TX, 77030 (United States); Ferrari, M. [Department of Biomedical Engineering, University of Texas at Austin, 1 University Station, Austin, TX, 78712 (United States); Department of Nanomedicine and Biomedical Engineering, Mehtodist Hospital Research Institute, 6565 Fannin Street, Houston, TX, 77030 (United States); Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Department of Bioengineering, Rice University, Houston, TX (United States)

    2011-06-15

    Porous silicon is an attractive biomaterial for drug delivery thanks to its biocompatibility, biodegradability, ease of fabrication, tunable nanostructure, and porous network. Herein we briefly present the development of a multi-stage delivery vector that leverages these advantages to enhance delivery of systemically administered therapeutic agents. We illustrate the rational design, objective-oriented fabrication and geometric control of first stage porous silicon microparticles. We describe how geometry affects the biodistribution of first stage vectors and how their porous structure affects the loading and release of second stage theranostic payloads. We describe the mechanism of cellular internalization and intracellular trafficking of particles. Finally we present two multi-stage vector prototypes for the delivery of magnetic resonance imaging contrast agents and small interfering RNA (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Quantitative Assessment of Synovial Vascularity Using Contrast-Enhanced Power Doppler Ultrasonography: Correlation with Histologic Findings and MR Imaging Findings in Arthritic Rabbit Knee Model

    International Nuclear Information System (INIS)

    Lee, Sang Hoon; Shin, Myung Jin; Kim, Seong Moon; Kim, Namkug; Suh, Sang Hyun; Suh, Jin Suck

    2008-01-01

    To validate contrast-enhanced power Doppler ultrasonography (PD US) for the evaluation of synovial vascularity in an arthritic rabbit knee model in correlation with MR and histological findings. Power Doppler ultrasonography was performed for carrageenin-induced arthritic left knee and control right knee of 13 rabbits, first without and then with sonic contrast agent enhancement (Levovist, Schering, Berlin Germany), followed by gadolinium-enhanced MR imaging. Synovial vascularity was quantitatively assessed by calculating the color pixel area in power Doppler sonography using a computer-aided image analysis program and by grading the enhancement on MR images: grade 1, enhancement of knee joint is less than one-third of the area; grade 2, one-third to two-thirds enhancement; and grade 3, more than two-thirds enhancement. Microvessel density (MVD) was measured on slides stained immunohistochemically for CD31 antigen for histological assessment. The mean area of color pixels in PD US changed from 4.37 to 16.42 mm 2 in the arthritic knee after enhancement (p 2 in the control knee (p 0.05). Sonic contrast-enhanced PD US improves the visualization of synovial vascularity and allows quantitative measurement in experimentally induced rabbit arthritic knees

  19. Contrast media. Safety issues and ESUR guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, H.S. (ed.) [Copenhagen Univ. Hospital, Herlev (Denmark). Dept. of Diagnostic Radiology 54E2

    2006-07-01

    In 1994 the European Society of Urogenital Radiology (ESUR) set up a committee to consider the safety of the contrast media used in radiology departments. Since then, the committee has questioned members, reviewed the literature, proposed guidelines, and discussed these proposals with participants at the annual symposia on urogenital radiology. This book represents the end result of this hard work. It contains all of the agreed guidelines, updated when necessary, and thereby comprehensively covers the many different safety issues relating to the diverse contrast media: barium contrast media, iodinated contrast media, MR contrast media (both gadolinium-based extracellular and organ-specific) and ultrasound contrast media. The prevention and treatment of both acute and delayed non-renal adverse reactions as well as the renal adverse reactions are covered in detail. The inclusion of all the ESUR guidelines within one book will offer an invaluable, unique and unparalleled resource. (orig.)

  20. Contrast media. Safety issues and ESUR guidelines

    International Nuclear Information System (INIS)

    Thomsen, H.S.

    2006-01-01

    In 1994 the European Society of Urogenital Radiology (ESUR) set up a committee to consider the safety of the contrast media used in radiology departments. Since then, the committee has questioned members, reviewed the literature, proposed guidelines, and discussed these proposals with participants at the annual symposia on urogenital radiology. This book represents the end result of this hard work. It contains all of the agreed guidelines, updated when necessary, and thereby comprehensively covers the many different safety issues relating to the diverse contrast media: barium contrast media, iodinated contrast media, MR contrast media (both gadolinium-based extracellular and organ-specific) and ultrasound contrast media. The prevention and treatment of both acute and delayed non-renal adverse reactions as well as the renal adverse reactions are covered in detail. The inclusion of all the ESUR guidelines within one book will offer an invaluable, unique and unparalleled resource. (orig.)