Helical High-Resolution Volume-Rendered 3-Dimensional Computer Tomography Angiography in the Detection of Intracranial Aneurysms

PurposeWe used an imaging technique based on 3-dimensional (3D) C-arm CT to assess the apposition of three types of stents after coiling of intracranial aneurysms.MethodsAll patients with intracranial aneurysms were considered who received stent-assisted coiling with Enterprise2, Neuroform EZ, or Neuroform Atlas stents confirmed by C-arm CT imaging at our institution between June 2015 and November 2017. A 3D digital subtraction angiography (DSA) scan for vessel imaging followed by a high-resolution cone beam CT (HR-CBCT) scan for coil and stent imaging was performed. The images were fused to obtain dual volume 3D fusion images. We investigated malapposition of the stent trunk (crescent sign) and of the stent edges (edge malapposition) and used the χ2 statistic to test for an association with stent types. Inter-rater agreement between two raters was estimated using Cohen’s kappa statistics.ResultsWe evaluated 75 consecutive cases. Enterprise2 stents were used in 22 cases, Neuroform EZ in 26, and Neuroform Atlas in 27 cases. By stent type, crescent sign was detected in 27% of Enterprise2, 8% of Neuroform EZ, and none of Neuroform Atlas stents (p=0.007), while edge malapposition was detected in 27% of Enterprise2, 58% of Neuroform EZ, and 30% of Neuroform Atlas stents (p=0.05). Excellent (κ=0.81) and good (κ=0.78) agreement between the raters was found for the detection of edge apposition and crescent sign, respectively.ConclusionStent malapposition was clearly visualized by dual volume 3D imaging. The Neuroform Atlas stents showed good apposition even in vessels with strong curvature.

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High resolution spot scan imaging of frozen, hydrated actin bundles with 400kV electrons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122964 ◽

1992 ◽

Vol 50 (1) ◽

pp. 512-513

Author(s):

J. Jakana ◽

M.F. Schmid ◽

P. Matsudaira ◽

W. Chiu

Keyword(s):

High Resolution ◽

Binding Proteins ◽

Actin Binding ◽

Eukaryotic Cells ◽

Dimensional Structure ◽

Structural Basis ◽

Actin Bundle ◽

Actin Bundles ◽

3 Dimensional ◽

Macromolecular Assembly

Actin is a protein found in all eukaryotic cells. In its polymerized form, the cells use it for motility, cytokinesis and for cytoskeletal support. An example of this latter class is the actin bundle in the acrosomal process from the Limulus sperm. The different functions actin performs seem to arise from its interaction with the actin binding proteins. A 3-dimensional structure of this macromolecular assembly is essential to provide a structural basis for understanding this interaction in relationship to its development and functions.

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High-Resolution Vessel Wall Magnetic Resonance Imaging of Small Unruptured Intracranial Aneurysms

Journal of Clinical Medicine ◽

10.3390/jcm10020225 ◽

2021 ◽

Vol 10 (2) ◽

pp. 225

Author(s):

Łukasz Zwarzany ◽

Ernest Tyburski ◽

Wojciech Poncyljusz

Keyword(s):

Magnetic Resonance Imaging ◽

Risk Factors ◽

Magnetic Resonance ◽

High Resolution ◽

Vessel Wall ◽

Intracranial Aneurysms ◽

Aneurysm Rupture ◽

Resonance Imaging ◽

Aneurysm Wall ◽

Conventional Risk Factors

Background: We decided to investigate whether aneurysm wall enhancement (AWE) on high-resolution vessel wall magnetic resonance imaging (HR VW-MRI) coexists with the conventional risk factors for aneurysm rupture. Methods: We performed HR VW-MRI in 46 patients with 64 unruptured small intracranial aneurysms. Patient demographics and clinical characteristics were recorded. The PHASES score was calculated for each aneurysm. Results: Of the 64 aneurysms, 15 (23.4%) showed wall enhancement on post-contrast HR VW-MRI. Aneurysms with wall enhancement had significantly larger size (p = 0.001), higher dome-to-neck ratio (p = 0.024), and a more irregular shape (p = 0.003) than aneurysms without wall enhancement. The proportion of aneurysms with wall enhancement was significantly higher in older patients (p = 0.011), and those with a history of prior aneurysmal SAH. The mean PHASES score was significantly higher in aneurysms with wall enhancement (p < 0.000). The multivariate logistic regression analysis revealed that aneurysm irregularity and the PHASES score are independently associated with the presence of AWE. Conclusions: Aneurysm wall enhancement on HR VW-MRI coexists with the conventional risk factors for aneurysm rupture.

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3-Dimensional Characterization of Polycrystalline Bulk Materials Using High-Energy Synchrotron Radiation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2353 ◽

2007 ◽

Vol 539-543 ◽

pp. 2353-2358 ◽

Cited By ~ 10

Author(s):

Ulrich Lienert ◽

Jonathan Almer ◽

Bo Jakobsen ◽

Wolfgang Pantleon ◽

Henning Friis Poulsen ◽

...

Keyword(s):

High Resolution ◽

Synchrotron Radiation ◽

High Energy ◽

Mapping Technique ◽

X Ray Diffraction ◽

Bulk Materials ◽

Reciprocal Space Mapping ◽

3 Dimensional ◽

Individual Grains

The implementation of 3-Dimensional X-Ray Diffraction (3DXRD) Microscopy at the Advanced Photon Source is described. The technique enables the non-destructive structural characterization of polycrystalline bulk materials and is therefore suitable for in situ studies during thermo-mechanical processing. High energy synchrotron radiation and area detectors are employed. First, a forward modeling approach for the reconstruction of grain boundaries from high resolution diffraction images is described. Second, a high resolution reciprocal space mapping technique of individual grains is presented.

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Detection of cervical spine trauma: Are 3-dimensional reconstructed images as accurate as multiplanar computer tomography?

Journal of Medical Imaging and Radiation Sciences ◽

10.1016/j.jmir.2021.04.004 ◽

2021 ◽

Author(s):

Asad Shakil ◽

Aeman Muneeb ◽

Muhammad Salman Khan ◽

Amir Humza Sohail ◽

Sameeha Ismail ◽

...

Keyword(s):

Cervical Spine ◽

Computer Tomography ◽

Cervical Spine Trauma ◽

Spine Trauma ◽

3 Dimensional

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Contrast agent volume in coronary computer tomography angiography—where are the limits?

Quantitative Imaging in Medicine and Surgery ◽

10.21037/qims-21-488 ◽

2021 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

Grigorios Korosoglou ◽

Sorin Giusca

Keyword(s):

Contrast Agent ◽

Computer Tomography ◽

Computer Tomography Angiography

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Optical Imaging of the Small Intestine Immune Compartments Across Scales

10.21203/rs.3.rs-1046138/v1 ◽

2021 ◽

Author(s):

Arielle Planchette ◽

Cédric Schmidt ◽

Olivier Burri ◽

Mercedes Gomez de Agüero ◽

Aleksandra Radenovic ◽

...

Keyword(s):

Spatial Distribution ◽

Small Intestine ◽

High Resolution ◽

Imaging Modality ◽

Regions Of Interest ◽

Label Free ◽

3 Dimensional ◽

Wide Range ◽

Mouse Small Intestine ◽

Made In

Abstract The limitations of 2D microscopy constrain our ability to observe and understand tissue-wide networks that are, by nature, 3-dimensional. Optical projection tomography enables the acquisition of large volumes (ranging from micrometres to centimetres) in various tissues, with label-free capacities for the observation of auto-fluorescent signals as well fluorescent-labelled targets of interest in multiple channels. We present a multi-modal workflow for the characterization of both structural and quantitative parameters of the mouse small intestine. As proof of principle, we evidence its applicability for imaging the mouse intestinal immune compartment and surrounding mucosal structures. We quantify the volumetric size and spatial distribution of Isolated Lymphoid Follicles (ILFs) and quantify density of villi throughout centimetre long segments of intestine. Furthermore, we exhibit the age- and microbiota-dependence for ILF development, and leverage a technique that we call reverse-OPT for identifying and homing in on regions of interest. Several quantification capabilities are displayed, including villous density in the autofluorescent channel and the size and spatial distribution of the signal of interest at millimetre-scale volumes. The concatenation of 3D image acquisition with the reverse-OPT sample preparation and a 2D high-resolution imaging modality adds value to interpretations made in 3D. This cross-modality referencing technique is found to provide accurate localisation of ROIs and to add value to interpretations made in 3D. Importantly, OPT may be used to identify sparsely-distributed regions of interest in large volumes whilst retaining compatibility with high-resolution microscopy modalities, including confocal microscopy. We believe this pipeline to be approachable for a wide-range of specialties, and to provide a new method for characterisation of the mouse intestinal immune compartment.

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