scholarly journals Gutter Characteristics and Stent Compression of Self-Expanding vs Balloon-Expandable Chimney Grafts in Juxtarenal Aneurysm Models

2020 ◽  
Vol 27 (3) ◽  
pp. 452-461
Author(s):  
Jorn P. Meekel ◽  
Theodorus G. van Schaik ◽  
Rutger J. Lely ◽  
Gerie Groot ◽  
Bram B. van der Meijs ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Fold Increase ◽  
The Other ◽  
Stent Grafts ◽  
Computed Tomography Scans ◽  
Different Types ◽  
Type Ia ◽  
Juxtarenal Aneurysm ◽  
Chimney Graft

Purpose: To assess in silicone juxtarenal aneurysm models the gutter characteristics and compression of different types of chimney graft (CG) configurations. Materials and Methods: Fifty-seven combinations of Excluder C3 or Conformable Excluder stent-grafts (23, 26, and 28.5 mm) were deployed in 2 silicone juxtarenal aneurysm models with 3 types of CGs: Viabahn self-expanding (VSE; 6 and 13 mm) or Viabahn balloon-expandable (VBX; 6, 10, and 12 mm) stent-grafts and Advanta V12 balloon-expandable stent-grafts (ABX; 6 and 12 mm). Setups were divided into 4 groups on the basis of increasing CG and main graft (MG) diameters. Two independent observers assessed gutter size and type as well as CG compression on computed tomography scans using postprocessing software. Results: In the smaller diameter combinations (6-mm CG and 23-, 26-, and 28.5-mm MGs), both VSE (p=0.006 to 0.050) and ABX (p=0.045 to 0.050) showed lower gutter areas and volumes compared with VBX. In turn, the VBX showed a nonsignificant tendency to decreased compression, especially compared to ABX. Use of the Excluder C3 showed a 6-fold increase in type A1 gutters (related to type Ia endoleak) as compared to the Conformable Excluder (p=0.018). Balloon-expandable stent-grafts (both ABX and VBX) showed a 3-fold increase in type A1 gutters in comparison with self-expanding stent-grafts (p=0.008). Conclusion: The current study suggests that use of the Conformable Excluder in combination with VSE chimney grafts is superior to the other tested CG/MG combinations in terms of gutter size, gutter type, and CG compression.

Morphological consequences of lateral outfracture of the inferior turbinate

2013 ◽  
Vol 127 (3) ◽  
pp. 323-328 ◽  
Author(s):  
B C Hanna ◽  
N Bailie ◽  
G Gallagher ◽  
J Cole
Keyword(s):  
Computed Tomography ◽  
Computer Modelling ◽  
Lateral Displacement ◽  
Inferior Turbinate ◽  
The Other ◽  
Nasal Airflow ◽  
Computed Tomography Scans ◽  
Appreciable Reduction

AbstractObjective:We report three cases of lateral outfracture of the inferior turbinate, which demonstrate a range of changes in the size, position and shape of the inferior turbinate.Method:During a study of the validity of computer modelling of nasal airflow, computed tomography scans of the noses of patients who had undergone lateral outfracture of the inferior turbinate were collected. The pre-operative scan was compared with the post-operative scan six weeks later.Results:In one patient, there was only a small lateral displacement of the inferior turbinate. In the other two cases, appreciable reduction in the volume of one inferior turbinate was noted, in addition to minor changes in the shape.Conclusion:Lateral outfracture of the inferior turbinate produces varied and inconsistent changes in morphology which may affect the shape, size and position of the turbinate.

scholarly journals The five digits of the giraffe metatarsal

2020 ◽  
Vol 131 (3) ◽  
pp. 699-705
Author(s):  
Laurel R Yohe ◽  
Nikos Solounias
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Fossil Record ◽  
The Other ◽  
Micro Computed Tomography ◽  
Common Assumption ◽  
Internal Morphology ◽  
Computed Tomography Scans ◽  
The Common ◽  
Taxonomic Groups

Abstract Evolution has shaped the limbs of hoofed animals in specific ways. In artiodactyls, it is the common assumption that the metatarsal is composed of the fusion of digits III and IV, whereas the other three digits have been lost or are highly reduced. However, evidence from the fossil record and internal morphology of the metatarsal challenges these assumptions. Furthermore, only a few taxonomic groups have been analysed. In giraffes, we discovered that all five digits are present in the adult metatarsal and are highly fused and modified rather than lost. We examined high-resolution micro-computed tomography scans of the metatarsals of two mid and late Miocene giraffid fossils and the extant giraffe and okapi. In all the Giraffidae analysed, we found a combination of four morphologies: (1) four articular facets; (2) four or, in most cases, five separate medullary cavities internally; (3) a clear, small digit I; and (4) in the two fossil taxa of unknown genus, the presence of external elongated grooves where the fusions of digits II and V have taken place. Giraffa and Okapia, the extant Giraffidae, show a difference from all the extinct taxa in having more flattened digits tightly packed together, suggesting convergent highly fused digits despite divergent ecologies and locomotion. These discoveries provide evidence that enhances our understanding of how bones fuse and call into question current hypotheses of digit loss.

scholarly journals Thoracic Endovascular Aortic Repair With Single/Double Chimney Technique for Aortic Arch Pathologies

2017 ◽  
Vol 24 (3) ◽  
pp. 383-393 ◽  
Author(s):  
Tun Wang ◽  
Chang Shu ◽  
Ming Li ◽  
Quan-ming Li ◽  
Xin Li ◽  
...  
Keyword(s):  
Aortic Dissection ◽  
Aortic Arch ◽  
Graft Patency ◽  
Type Ii ◽  
Stent Grafts ◽  
Type Ii Endoleak ◽  
Chimney Technique ◽  
Type Ia ◽  
Chimney Graft

Purpose: To summarize a single-center experience using the single/double chimney technique in association with thoracic endovascular aortic repairs (TEVAR) for aortic arch pathologies. Methods: From November 2007 to March 2016, 122 patients (mean age 50.4±12.7 years, range 29–80; 92 men) with aortic arch pathologies underwent TEVAR combined with single (n=101) or double (n=21) chimney grafts to reconstruct the supra-aortic branches: 21 innominate arteries, 114 left common carotid arteries, and 8 left subclavian arteries (LSA). Pathologies included type B aortic dissection (n=47), aortic arch dissection (n=49), retrograde type A aortic dissection (n=8), thoracic aortic aneurysm (n=7), penetrating aortic arch ulcer (n=9), and post-TEVAR type I endoleak (n=2). Follow-up examinations included computed tomography at 0.5, 3, 6, and 12 months and yearly thereafter. Results: The aortic stent-grafts were deployed in zone 0 (n=21), zone 1 (n=93), and zone 2 (n=8). One (0.8%) of the 122 patients died at 4 days due to a perforated peptic ulcer. Type Ia endoleaks were found intraoperatively in 13 (10.7%) patients, including 3 with the double chimney technique. Type II endoleaks occurred in 6 (4.9%) patients; 3 were treated with duct occluders in the LSA. Postoperative chimney graft migration occurred in 1 (0.8%) patient with double chimneys; additional stent-grafts were deployed in both chimneys. Median follow-up was 32.3 months, during which 1 (0.8%) patient died after a stroke at 3 months. Chimney stent-graft patency was observed in the remaining 120 patients. Two (1.7%) secondary TEVARs were performed for distal aortic dissection. Nine asymptomatic type Ia endoleaks and 1 type II endoleak persisted in follow-up; a type II endoleak in 1 patient with Marfan syndrome sealed in 52 months. Conclusion: TEVAR with the chimney technique provides a safe, minimally invasive alternative with good chimney graft patency and low postoperative mortality during midterm follow-up. The double chimney technique should be used judiciously owing to its potential complications.

scholarly journals Collected Transatlantic Experience From the PERICLES Registry: Use of Chimney Grafts to Treat Post-EVAR Type Ia Endoleaks Shows Good Midterm Results

2018 ◽  
Vol 25 (4) ◽  
pp. 492-498 ◽  
Author(s):  
Sonia Ronchey ◽  
Stefano Fazzini ◽  
Salvatore Scali ◽  
Giovanni Torsello ◽  
Paul Kubilis ◽  
...  
Keyword(s):  
Endovascular Aneurysm Repair ◽  
Primary Patency ◽  
Graft Occlusion ◽  
Technical Success ◽  
Stent Grafts ◽  
Midterm Results ◽  
Type Ia ◽  
Aneurysm Repair ◽  
Chimney Graft

Purpose: The aim of this retrospective analysis was to evaluate the performance of the chimney (ch) technique in the treatment of type Ia endoleaks after standard endovascular aneurysm repair (EVAR). Methods: Between January 2008 and December 2014, 517 chEVAR procedures were performed in 13 US and European vascular centers (PERICLES registry). Thirty-nine patients (mean age 76.9±7.1 years; 33 men) were treated for persistent type Ia endoleak and had computed tomography angiography or magnetic resonance angiography follow-up at >1 month. Endurant abdominal stent-grafts were used in the 20 cases. Single chimney graft placement was performed in 18 (46%) patients and multiple in 21 (54%). Overall, 70 visceral vessels were targeted for revascularization. Results: Technical success was achieved in 35 (89.7%) cases; 3 persistent type Ia endoleaks and 1 chimney graft occlusion were detected within the first 30 days. Thirty-day mortality was 2.6%. Two other deaths (not aneurysm related) occurred during a mean follow-up of 21.9 months (0.23–71.3). Primary patency of the chimney grafts was 94.3% at 36 months. In a subgroup analysis comparing Endurant to other stent-grafts, no significant differences were observed regarding persistent endoleak [1/20 (5%) vs 2/19 (11%), p=0.6] or reintervention [1/20 (5%) vs 0/19 (0%)]. Conclusion: The present series demonstrates that chEVAR in the treatment of post-EVAR type Ia endoleaks has satisfactory results independent of the abdominal and chimney graft combinations. Midterm results show that chEVAR is an effective method for treating type Ia endoleaks.

scholarly journals Deep Learning Applied to Intracranial Hemorrhage Detection

2021 ◽  
Author(s):  
Luis Cortes-Ferre ◽  
Miguel Angel Gutiérrez-Naranjo ◽  
Juan José Egea-Guerrero ◽  
Marcin Balcerzyk
Keyword(s):  
Computed Tomography ◽  
Deep Learning ◽  
Intracranial Hemorrhage ◽  
The Other ◽  
Patient Diagnosis ◽  
Learning Techniques ◽  
Computed Tomography Scans ◽  
Novel Method ◽  
The One ◽  
Urgent Procedure

Intracranial hemorrhage is a serious health problem requiring rapid and often intensive medical care. Identifying the location and type of any hemorrhage present is a critical step in treating the patient. Diagnosis requires an urgent procedure and the detection of the hemorrhage is a hard and time-consuming process for human experts. In this paper, we propose a novel method based on Deep Learning techniques which can be useful as decision support system. Our proposal is two-folded. On the one hand, the proposed technique classifies slices of computed tomography scans for hemorrhage existence or not, achieving 92.7% accuracy and 0.978 ROC-AUC. On the other hand, our method provides visual explanation to the chosen classification by using the so-called Grad-CAM method. TRANSLATE with x English ArabicHebrewPolish BulgarianHindiPortuguese CatalanHmong DawRomanian Chinese SimplifiedHungarianRussian Chinese TraditionalIndonesianSlovak CzechItalianSlovenian DanishJapaneseSpanish DutchKlingonSwedish EnglishKoreanThai EstonianLatvianTurkish FinnishLithuanianUkrainian FrenchMalayUrdu GermanMalteseVietnamese GreekNorwegianWelsh Haitian CreolePersian TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster Portal Back TRANSLATE with x English ArabicHebrewPolish BulgarianHindiPortuguese CatalanHmong DawRomanian Chinese SimplifiedHungarianRussian Chinese TraditionalIndonesianSlovak CzechItalianSlovenian DanishJapaneseSpanish DutchKlingonSwedish EnglishKoreanThai EstonianLatvianTurkish FinnishLithuanianUkrainian FrenchMalayUrdu GermanMalteseVietnamese GreekNorwegianWelsh Haitian CreolePersian TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster Portal Back

scholarly journals Deep Learning based Staging of Bone Lesions from Computed Tomography Scans (January 2021)

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Samira Masoudi ◽  
Sherif Mehralivand ◽  
Stephanie A. Harmon ◽  
Nathan Lay ◽  
Liza Lindenberg ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Deep Learning ◽  
Bone Lesions ◽  
Computed Tomography Scans

scholarly journals Evaluation of Cytotoxic and Mutagenic Effects of the Synthetic Cathinones Mexedrone, α-PVP and α-PHP

2021 ◽  
Vol 22 (12) ◽  
pp. 6320
Author(s):  
Monia Lenzi ◽  
Veronica Cocchi ◽  
Sofia Gasperini ◽  
Raffaella Arfè ◽  
Matteo Marti ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Metabolic Activation ◽  
Fold Increase ◽  
Synthetic Cathinones ◽  
The Other ◽  
Oxygen Species ◽  
Genetic Damage ◽  
Mutagenic Potential ◽  
Tk6 Cells ◽  
Mutagenic Effects

Mexedrone, α-PVP and α-PHP are synthetic cathinones. They can be considered amphetamine-like substances with a stimulating effect. Actually, studies showing their impact on DNA are totally absent. Therefore, in order to fill this gap, aim of the present work was to evaluate their mutagenicity on TK6 cells. On the basis of cytotoxicity and cytostasis results, we selected the concentrations (35–100 µM) to be used in the further analysis. We used the micronucleus (MN) as indicator of genetic damage and analyzed the MNi frequency fold increase by flow cytometry. Mexedrone demonstrated its mutagenic potential contrary to the other two compounds; we then proceeded by repeating the analyzes in the presence of extrinsic metabolic activation in order to check if it was possible to totally exclude the mutagenic capacity for α-PVP and α-PHP. The results demonstrated instead the mutagenicity of their metabolites. We then evaluated reactive oxygen species (ROS) induction as a possible mechanism at the basis of the highlighted effects but the results did not show a statistically significant increase in ROS levels for any of the tested substances. Anyway, our outcomes emphasize the importance of mutagenicity evaluation for a complete assessment of the risk associated with synthetic cathinones exposure.

Correlation between tympanometry volume and three-dimensional computed tomography mastoid volumetry in tympanoplasty candidates

2021 ◽  
pp. 1-5
Author(s):  
L Epprecht ◽  
L Qingsong ◽  
N Stenz ◽  
S Hashimi ◽  
T Linder
Keyword(s):  
Computed Tomography ◽  
Tympanic Membrane ◽  
Cell Volume ◽  
Radiation Injury ◽  
Three Dimensional ◽  
Non Invasive ◽  
Tympanic Membrane Perforations ◽  
Computed Tomography Scans ◽  
Air Cells ◽  
Mastoid Air Cells

Abstract Objective Ventilation of the middle ear and mastoid air cells is believed to play an important role in the pathogenesis of chronic ear disease. Traditionally, ventilation is assessed by computed tomography. However, this exposes patients to cumulative radiation injury. In cases with a perforation in the tympanic membrane, tympanometry potentially presents a non-invasive alternative to measure the ventilated middle-ear and mastoid air cell volume. This study hypothesised that total tympanometry volume correlates with ventilated middle-ear and mastoid air cell volume. Method Total tympanometry volume was compared with ventilated middle-ear and mastoid air cell volume on computed tomography scans in 20 tympanic membrane perforations. Results There was a high correlation between tympanometry and computed tomography volumes (r = 0.78; p < 0.001). A tympanometry volume more than 2 ml predicted good ventilation on computed tomography. Conclusion These results may help reduce the need for pre-operative computed tomography in uncomplicated cases with tympanic membrane perforations.

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