T1-hyperintense renal lesions: can high signal predict lack of enhancement?

2015 ◽  
Vol 40 (8) ◽  
pp. 3175-3181 ◽  
Author(s):  
Jenna Le ◽  
Milana Flusberg ◽  
Alla M. Rozenblit ◽  
Victoria Chernyak
Keyword(s):  
High Signal ◽  
Renal Lesions

Acquisition of EELS spectra for high-resolution spectroscopy

1993 ◽  
Vol 51 ◽  
pp. 578-579
Author(s):  
Maoxu Qian ◽  
Mehmet Sarikaya ◽  
Edward A. Stern
Keyword(s):  
Energy Loss ◽  
Detection System ◽  
High Resolution Spectroscopy ◽  
High Signal ◽  
Short Report ◽  
Edge Structure ◽  
High Background ◽  
Gain Variation ◽  
Sufficient Energy ◽  
On Line

It is difficult, in general, to perform quantitative EELS to determine, for example, relative or absolute compositions of elements with relatively high atomic numbers (using, e.g., K edge energies from 500 eV to 2000 eV), to study ELNES (energy loss near edge structure) signal using the white lines to determine oxidation states, and to analyze EXELFS (extended energy loss fine structure) to study short range ordering. In all these cases, it is essential to have high signal-to-noise (S/N) ratio (low systematical error) with high overall counts, and sufficient energy resolution (∽ 1 eV), requirements which are, in general, difficult to attain. The reason is mainly due to three important inherent limitations in spectrum acquisition with EELS in the TEM. These are (i) large intrinsic background in EELS spectra, (ii) channel-to-channel gain variation (CCGV) in the parallel detection system, and (iii) difficulties in obtaining statistically high total counts (∽106) per channel (CH). Except the high background in the EELS spectrum, the last two limitations may be circumvented, and the S/N ratio may be attained by the improvement in the on-line acquisition procedures. This short report addresses such procedures.

The diagnostic utility of pericholecystic high signal by magnetic resonance cholangiography in the patient with acute cholecystitis

2001 ◽  
Vol 120 (5) ◽  
pp. A577-A577
Author(s):  
T SEKI ◽  
M FURUKAWA ◽  
M OGIHARA ◽  
Y MAGAMI ◽  
T HORIBE ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Acute Cholecystitis ◽  
Magnetic Resonance Cholangiography ◽  
High Signal ◽  
Diagnostic Utility

1913: The Radiographic Evolution of Radio Frequency Ablated Renal Lesions

2004 ◽  
Vol 171 (4S) ◽  
pp. 505-505
Author(s):  
Edward D. Matsumoto ◽  
Lori Watumall ◽  
D. Brooke Johnson ◽  
Kenneth Ogan ◽  
Grant D. Taylor ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Renal Lesions

Liquoid Induced Stasis and the Generalized Shwartzman Reaction

1979 ◽  
Vol 41 (04) ◽  
pp. 804-810 ◽  
Author(s):  
Knut Nordstoga
Keyword(s):  
Red Cells ◽  
Renal Lesions ◽  
Intravenous Injections ◽  
Shwartzman Reaction ◽  
Glomerular Capillaries

SummaryThe composition of the occlusive material within dilated glomerular capillaries, following intravenous injections of Liquoid in blue foxes, was studied electron microscopically; it was found that it mainly consisted of a debris in which disintegrated red cells constituted the major component. Damaged platelets and necrotic endothelial remnants were other components. These observations were interpreted as a result of glomerular stasis, and it was concluded that stasis in glomerular capillaries is a basic event in the development of the renal lesions accompanying the generalized Shwartzman reaction.

A Re-Appraisal of the Role of Blood Coagulation and Platelets in the Generalized Shwartzman Phenomenon

1966 ◽  
Vol 15 (03/04) ◽  
pp. 519-538 ◽  
Author(s):  
J Levin ◽  
E Beck
Keyword(s):  
Blood Coagulation ◽  
The State ◽  
Coagulation System ◽  
Renal Lesions ◽  
Intravascular Coagulation ◽  
Renal Glomeruli ◽  
Coagulation Mechanism ◽  
Shwartzman Phenomenon ◽  
Do So

SummaryThe role of intravascular coagulation in the production of the generalized Shwartzman phenomenon has been evaluated. The administration of endotoxin to animals prepared with Thorotrast results in activation of the coagulation mechanism with the resultant deposition of fibrinoid material in the renal glomeruli. Anticoagulation prevents alterations in the state of the coagulation system and inhibits development of the renal lesions. Platelets are not primarily involved. Platelet antiserum produces similar lesions in animals prepared with Thorotrast, but appears to do so in a manner which does not significantly involve intravascular coagulation.The production of adrenal cortical hemorrhage, comparable to that seen in the Waterhouse-Friderichsen syndrome, following the administration of endotoxin to animals that had previously received ACTH does not require intravascular coagulation and may not be a manifestation of the generalized Shwartzman phenomenon.

EVALUATION OF FOCAL RENAL LESIONS WITH CONTRAST ENHANCED GREY-SCALE HARMONIC ULTRASOUND

2005 ◽  
Vol 26 (S 1) ◽  
Author(s):  
F Frauscher ◽  
L Pallwein ◽  
J Gradl ◽  
M Schurich ◽  
A Pelzer ◽  
...  
Keyword(s):  
Renal Lesions ◽  
Grey Scale ◽  
Contrast Enhanced

Attempt at differentiation of solid renal lesions by CEUS

2007 ◽  
Vol 28 (S 1) ◽  
Author(s):  
A Lewicki ◽  
M Jêdrzejczyk ◽  
W Jakubowski ◽  
W Pypno ◽  
P Marczyñski ◽  
...  
Keyword(s):  
Renal Lesions

A compact guided-wave EMAT with pulsed electromagnet for ferromagnetic tube inspection

2020 ◽  
Vol 64 (1-4) ◽  
pp. 951-958
Author(s):  
Tianhao Liu ◽  
Yu Jin ◽  
Cuixiang Pei ◽  
Jie Han ◽  
Zhenmao Chen
Keyword(s):  
Power Plants ◽  
Signal To Noise Ratio ◽  
Small Diameter ◽  
Performance Testing ◽  
Guided Wave ◽  
High Signal ◽  
Receiver Coil ◽  
Signal To Noise ◽  
Corrosion Defects

Small-diameter tubes that are widely used in petroleum industries and power plants experience corrosion during long-term services. In this paper, a compact inserted guided-wave EMAT with a pulsed electromagnet is proposed for small-diameter tube inspection. The proposed transducer is noncontact, compact with high signal-to-noise ratio and unattractive to ferromagnetic tubes. The proposed EMAT is designed with coils-only configuration, which consists of a pulsed electromagnet and a meander pulser/receiver coil. Both the numerical simulation and experimental results validate its feasibility on generating and receiving L(0,2) mode guided wave. The parameters for driving the proposed EMAT are optimized by performance testing. Finally, feasibility on quantification evaluation for corrosion defects was verified by experiments.

Clinical Manifestations and Radiological Characteristics on Rosai-Dorfman Disease: A Retrospective Observational Study

2020 ◽  
Vol 5 (5) ◽  
Keyword(s):  
Blood Vessels ◽  
Abdominal Cavity ◽  
Clinical Manifestations ◽  
Ct Images ◽  
High Signal ◽  
Radiological Features ◽  
Imaging Characteristics ◽  
Rosai Dorfman Disease ◽  
Heterogeneous Enhancement ◽  
The Masses

Background and Objective: Rosai-Dorfman disease (RDD) are usually misdiagnosed because of rarity and nonspecific clinical and radiological features. The aim of our study is to explore the clinical and imaging characteristics of RDD to improve diagnostic accuracy. Methods: Clinical and imaging data in 10 patients with RDD were retrospectively analyzed. 7 patients were underwent CT scanning and 3 patients were underwent MR examination. Results: 8 (8/10) patients presented with painless enlarged lymph nodes (LNs) or mass. 3 cases were involved with LNs, 5 cases were involved with extra-nodal tissues, and the remaining 2 cases were involved with LNs and extra-nodal tissue simultaneously. In enhanced CT images, enlarged LNs displayed mild or moderate enhancement, and 2 cases showed heterogeneous ring-enhancement. MR features of 3 patients with extra-nodal RDD, 2 cases showed a mass located in the subcutaneous and anterior abdominal wall respectively, and 1 case showed an intracranial mass. Besides, all lesions showed high signal foci on DWI images, and were characterized by marked heterogeneous enhancement with blurred edge. The dural/fascia tail sign and dilated blood vessels could be seen around all the lesions on enhanced MRI. Radiological features of 2 cases with LN and extranodal tissue involved, one case presented with the swelling and thickening of pharyngeal lymphoid ring and nasopharynx, meanwhile with enlarged LNs in bilateral submandibular area, neck and abdominal cavity, and also companied with osteolytic lesion in right proximal humerus. All these LNs displayed mild and moderate enhancement on CT images. Another case showed enlarged LNs in bilateral neck accompanied with soft tissue mass in the sinuses. Conclusions: RDD occurred commonly in young and middle-aged men and presented with painless enlarged LNs or mass.RDD had a huge diversity of imaging findings, which varied with different location. The radiological features, such as small patches of high signal foci in the masses on DWI images, heterogeneous enhancement and blood vessels around the masses, are helpful in diagnosis of extranodal RDD.

Tantalum Oxide Nanoparticles as Versatile Contrast Agents for X-ray Computed Tomography

2020 ◽  
Author(s):  
Shatadru Chakravarty ◽  
Jeremy Hix ◽  
Kaitlyn Wieweora ◽  
Maximilian Volk ◽  
Elizabeth Kenyon ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Contrast Agents ◽  
Mesoporous Silica Nanoparticles ◽  
Sol Gel ◽  
Tantalum Oxide ◽  
High Signal ◽  
Drug Delivery Vehicles ◽  
X Ray Computed

Here we describe the synthesis, characterization and in vitro and in vivo performance of a series of tantalum oxide (TaOx) based nanoparticles (NPs) for computed tomography (CT). Five distinct versions of 9-12 nm diameter silane coated TaOx nanocrystals (NCs) were fabricated by a sol-gel method with varying degrees of hydrophilicity and with or without fluorescence, with the highest reported Ta content to date (78%). Highly hydrophilic NCs were left bare and were evaluated in vivo in mice for micro-CT of full body vasculature, where following intravenous injection, TaOx NCs demonstrate high CT contrast, circulation in blood for ~ 3 h, and eventual accumulation in RES organs; and following injection locally in the mammary gland, where the full ductal tree structure can be clearly delineated. Partially hydrophilic NCs were encapsulated within mesoporous silica nanoparticles (MSNPs; TaOx@MSNPs) and hydrophobic NCs were encapsulated within poly(lactic-co-glycolic acid) (PLGA; TaOx@PLGA) NPs, serving as potential CT-imagable drug delivery vehicles. Bolus intramuscular injections of TaOx@PLGA NPs and TaOx@MSNPs to mimic the accumulation of NPs at a tumor site produce high signal enhancement in mice. In vitro studies on bare NCs and formuated NPs demonstrate high cytocompatibility and low dissolution of TaOx. This work solidifies that TaOx-based NPs are versatile contrast agents for CT.

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