scholarly journals ICVTS on-line discussion A Patency of distal false lumen in acute dissection

2006 ◽  
Vol 6 (2) ◽  
pp. 207-208 ◽  
Author(s):  
J. Bachet
Keyword(s):  
False Lumen ◽  
On Line ◽  
Acute Dissection

scholarly journals Chronic Type A Aortic Dissection

Aorta ◽  
2016 ◽  
Vol 04 (01) ◽  
pp. 16-21 ◽  
Author(s):  
Conor Hynes ◽  
Michael Greenberg ◽  
Shawn Sarin ◽  
Gregory Trachiotis
Keyword(s):  
Aortic Dissection ◽  
Surgical Repair ◽  
False Lumen ◽  
Disease Process ◽  
Type A ◽  
Delayed Presentation ◽  
Chronic Type ◽  
Type A Aortic Dissection ◽  
First Line Therapy ◽  
Acute Dissection

AbstractStanford Type A aortic dissection is a rapidly progressing disease process that is often fatal without emergent surgical repair. A small proportion of Type A dissections go undiagnosed in the acute phase and are found upon delayed presentation of symptoms or incidentally. These chronic lesions may have a distinct natural history that may have a better prognosis and could potentially be managed differently then those presenting acutely. The method of repair depends on location and extent of the false lumen, as well as involvement of critical structures and branch arteries. Surgical repair techniques similar to those employed for acute dissection management are currently first-line therapy for chronic cases that involve the aortic valve, sinuses of Valsalva, coronary arteries, and supra-aortic branch arteries. In patients with high-risk for surgery, endovascular repairs have been successful, and active development of delivery systems and grafts will continue to enhance outcomes. We present two cases of chronic Type A aortic dissection and review the current literature.

scholarly journals Aortic dissection in Siriraj patients: Computed tomography findings

2017 ◽  
Vol 19 (3) ◽  
pp. 5-25
Author(s):  
Krisdee Prabhasavat ◽  
Sukrit Sorotpinya ◽  
Jitladda Wasinrat ◽  
Somchai Chairoongruang
Keyword(s):  
Aortic Dissection ◽  
Acute Aortic Dissection ◽  
False Lumen ◽  
Type A ◽  
Outer Wall ◽  
Type B ◽  
Computed Tomographic ◽  
Wall Calcification ◽  
Acute Dissection ◽  
Aortic Dissections

Background: CTA has replaced angiography in both diagnosis and evaluation of aortic dissection. Most findings are associated with true and false lumens which account for the most important information in both diagnosis and management. Objective: To describe computed tomographic (CT) findings including types based on Stanford classification, true and false lumens, acute and chronic aortic dissections, relation to origins of aortic branches, complications and other related findings. Methods: Computed tomographic angiography (CTA) scans of one hundred and twenty patients with aortic dissection during 2007 to 2016 were retrospectively reviewed. The findings indicating types, true and false lumens, acute and chronic, origination of aortic branches, complication and other related findings are categorized. Result: Most true lumens were smaller, having outer wall calcification. Most false lumens were larger, showing beak sign, cobweb sign, and intraluminal thrombi. However, the larger lumens could be true lumens as well as the smaller lumen could be a false lumen and outer wall calcification could be seen in a false lumen. The larger true lumens and the smaller false lumens with outer wall calcifications were more often found in chronic aortic dissection than acute aortic dissection. Both acute and chronic aortic dissections were more Stanford type B than type A. Complications included rupture, hemopericardium, hemothorax, hemomediastinum and distal organ infarction, which were more frequent in acute dissection. Intrathoracic complications were more commonly caused by type A acute dissection. Renal infarction was the most common complication in type B acute aortic dissection. Conclusion: Most CT fi ndings of aortic dissection in this study were typical. Atypical fi ndings were also found in both acute and chronic aortic dissections. Outer wall calcifi cations of false lumens in acute aortic dissection were found in 2 cases.

scholarly journals Incorrect frozen elephant trunk deployment into the false lumen of a patient with complicated type B acute dissection

2018 ◽  
Vol 55 (6) ◽  
pp. 1222-1224 ◽  
Author(s):  
Masahiko Fujii ◽  
Hiroyuki Watanabe ◽  
Masayoshi Otsu ◽  
Yuta Sugahara
Keyword(s):  
False Lumen ◽  
Type B ◽  
Frozen Elephant Trunk ◽  
Elephant Trunk ◽  
Acute Dissection

Combined Ascending Aortic Stent-Graft and Inner Branched Arch Device for Type A Aortic Dissection

2018 ◽  
Vol 25 (5) ◽  
pp. 561-565 ◽  
Author(s):  
Yuk Law ◽  
Nikolaos Tsilimparis ◽  
Fiona Rohlffs ◽  
Vladimir Makaloski ◽  
E. Sebastian Debus ◽  
...  
Keyword(s):  
Aortic Dissection ◽  
Stent Graft ◽  
False Lumen ◽  
Type A ◽  
Type I ◽  
Type A Aortic Dissection ◽  
Landing Zone ◽  
Aortic Stent Graft ◽  
Limited Experience ◽  
Acute Dissection

Purpose: To report the use of the Zenith Ascend stent-graft in conjunction with the Zenith inner branched arch device to treat type A aortic dissection. Case Report: Five patients (mean age 66 years, range 52–78; 4 men) with type A aortic dissection (2 acute) and insufficient distal landing zones were treated with the Zenith Ascend stent-graft and inner branched arch devices to extend the distal landing zone. Left carotid–subclavian bypass was performed in a staged or simultaneous setting depending on the urgency of the condition. Technical success (no type I or III endoleak and successful revascularization of all supra-aortic vessels) was achieved in all patients. Median intensive care unit stay was 5 days (range 4–23) and the median hospital stay was 16 days (range 8–25). The 2 patients with acute dissection died in hospital and at 5 months, respectively. The 3 elective patients were followed for 7, 13, and 19 months, respectively. All had false lumen thrombosis with either a reduced or stable aneurysm diameter. Conclusion: This limited experience demonstrated the feasibility and safety of the combined use of the Ascend stent-graft and inner branched arch devices. This strategy may sometimes be more beneficial than either stent-graft used alone.

scholarly journals Aortic dissection in Siriraj patients: Computed tomography findings

2017 ◽  
pp. 5-25
Author(s):  
Krisdee Prabhasavat ◽  
Sukrit Sorotpinya ◽  
Jitladda Wasinrat ◽  
Somchai Chairoongruang
Keyword(s):  
Aortic Dissection ◽  
Acute Aortic Dissection ◽  
False Lumen ◽  
Type A ◽  
Outer Wall ◽  
Type B ◽  
Computed Tomographic ◽  
Wall Calcification ◽  
Acute Dissection ◽  
Aortic Dissections

Background: CTA has replaced angiography in both diagnosis and evaluation of aortic dissection. Most findings are associated with true and false lumens which account for the most important information in both diagnosis and management. Objective: To describe computed tomographic (CT) findings including types based on Stanford classification, true and false lumens, acute and chronic aortic dissections, relation to origins of aortic branches, complications and other related findings. Methods: Computed tomographic angiography (CTA) scans of one hundred and twenty patients with aortic dissection during 2007 to 2016 were retrospectively reviewed. The findings indicating types, true and false lumens, acute and chronic, origination of aortic branches, complication and other related findings are categorized. Result: Most true lumens were smaller, having outer wall calcification. Most false lumens were larger, showing beak sign, cobweb sign, and intraluminal thrombi. However, the larger lumens could be true lumens as well as the smaller lumen could be a false lumen and outer wall calcification could be seen in a false lumen. The larger true lumens and the smaller false lumens with outer wall calcifications were more often found in chronic aortic dissection than acute aortic dissection. Both acute and chronic aortic dissections were more Stanford type B than type A. Complications included rupture, hemopericardium, hemothorax, hemomediastinum and distal organ infarction, which were more frequent in acute dissection. Intrathoracic complications were more commonly caused by type A acute dissection. Renal infarction was the most common complication in type B acute aortic dissection. Conclusion: Most CT fi ndings of aortic dissection in this study were typical. Atypical fi ndings were also found in both acute and chronic aortic dissections. Outer wall calcifi cations of false lumens in acute aortic dissection were found in 2 cases.

Toward the Best Treatment for Uncomplicated Patients With Type B Acute Aortic Dissection

Circulation ◽  
1999 ◽  
Vol 100 (suppl_2) ◽  
Author(s):  
Akira Marui ◽  
Takaaki Mochizuki ◽  
Norimasa Mitsui ◽  
Tadaaki Koyama ◽  
Fumiko Kimura ◽  
...  
Keyword(s):  
Aortic Dissection ◽  
Acute Phase ◽  
Acute Aortic Dissection ◽  
False Lumen ◽  
Chronic Phase ◽  
Aortic Diameter ◽  
Type B ◽  
Hypotensive Therapy ◽  
Acute Dissection ◽  
Patent False Lumen

Background —In the treatment of type B acute aortic dissection without complications, better results are obtained if surgery is performed before enlargement of the aorta in patients who are predicted to show aortic enlargement and if drug-based treatment is continued for patients who are predicted to show no enlargement. The purpose of this study was to predict the acute-phase factors that may affect chronic-phase aortic enlargement by studying chronic-phase enlargement of dissections in patients without complications during the acute phase. Methods and Results —In 101 patients with type B acute dissection who had no complications, univariate and multivariate factor analyses were performed to determine the predictors for chronic-phase enlargement (≥60 mm) of the dissected aorta. The independent predominant predictors for aortic enlargement in the chronic phase were a maximum aortic diameter of ≥40 mm and a patent false lumen during the acute phase. The values of actuarial freedom from aortic enlargement for the patients with a maximum aortic diameter of 40 mm and a patent false lumen at 1, 5, and 10 years were 43%, 33%, and 22%, respectively, whereas in patients with a maximum aortic diameter of <40 mm and a closed false lumen, the values were 97%, 94%, and 84%, respectively. Conclusions —These results suggest that patients with type B acute aortic dissection who show a maximum aortic diameter of ≥40 mm and a patent false lumen should undergo surgery earlier during the chronic phase before enlargement of aorta, whereas patients with a maximum aortic diameter of <40 mm and a closed false lumen should continue to receive hypotensive therapy.

scholarly journals Patency of distal false lumen in acute dissection: extent of resection and prognosis

2006 ◽  
Vol 6 (2) ◽  
pp. 204-207 ◽  
Author(s):  
G. Sakaguchi ◽  
T. Komiya ◽  
N. Tamura ◽  
C. Kimura ◽  
T. Kobayashi ◽  
...  
Keyword(s):  
False Lumen ◽  
Extent Of Resection ◽  
Acute Dissection

The on-line use of histogram data for high-speed correction and alignment of electron microscope images

1984 ◽  
Vol 42 ◽  
pp. 556-557
Author(s):  
William Krakow
Keyword(s):  
Power Spectrum ◽  
High Speed ◽  
Direct Memory Access ◽  
Digital Television ◽  
Contrast Transfer Function ◽  
The Past ◽  
High Resolution Tem ◽  
On Line ◽  
Correction Of Astigmatism ◽  
The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

Image registration with a computer driven S.T.E.M.

1978 ◽  
Vol 36 (1) ◽  
pp. 98-99
Author(s):  
A.M.H. Schepman ◽  
J.A.P. van der Voort ◽  
J.E. Mellema
Keyword(s):  
Spot Size ◽  
Scanning Transmission Electron Microscope ◽  
Small Computer ◽  
Structural Studies ◽  
Area Of Interest ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Specimen Area ◽  
On Line ◽  
Minimum Distances

A Scanning Transmission Electron Microscope (STEM) was coupled to a small computer. The system (see Fig. 1) has been built using a Philips EM400, equipped with a scanning attachment and a DEC PDP11/34 computer with 34K memory. The gun (Fig. 2) consists of a continuously renewed tip of radius 0.2 to 0.4 μm of a tungsten wire heated just below its melting point by a focussed laser beam (1). On-line operation procedures were developped aiming at the reduction of the amount of radiation of the specimen area of interest, while selecting the various imaging parameters and upon registration of the information content. Whereas the theoretical limiting spot size is 0.75 nm (2), routine resolution checks showed minimum distances in the order 1.2 to 1.5 nm between corresponding intensity maxima in successive scans. This value is sufficient for structural studies of regular biological material to test the performance of STEM over high resolution CTEM.

Design and calibration of an IVEM for general 3-dimensional imaging of non-diffracting materials

1992 ◽  
Vol 50 (2) ◽  
pp. 1040-1041
Author(s):  
Neil Rowlands ◽  
Jeff Price ◽  
Michael Kersker ◽  
Seichi Suzuki ◽  
Steve Young ◽  
...  
Keyword(s):  
3D Imaging ◽  
Tomographic Reconstruction ◽  
Three Dimensional ◽  
3 Dimensional ◽  
3D Microstructure ◽  
Image Translation ◽  
Digital Correlation ◽  
On Line ◽  
Mechanical Stage ◽  
Projection Angle

Three-dimensional (3D) microstructure visualization on the electron microscope requires that the sample be tilted to different positions to collect a series of projections. This tilting should be performed rapidly for on-line stereo viewing and precisely for off-line tomographic reconstruction. Usually a projection series is collected using mechanical stage tilt alone. The stereo pairs must be viewed off-line and the 60 to 120 tomographic projections must be aligned with fiduciary markers or digital correlation methods. The delay in viewing stereo pairs and the alignment problems in tomographic reconstruction could be eliminated or improved by tilting the beam if such tilt could be accomplished without image translation.A microscope capable of beam tilt with simultaneous image shift to eliminate tilt-induced translation has been investigated for 3D imaging of thick (1 μm) biologic specimens. By tilting the beam above and through the specimen and bringing it back below the specimen, a brightfield image with a projection angle corresponding to the beam tilt angle can be recorded (Fig. 1a).

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