Micro-CT-Based Quantification of Extracted Thrombus Burden Characteristics and Association With Angiographic Outcomes in Patients With ST-Elevation Myocardial Infarction: The QUEST-STEMI Study

Background: Angiographic detection of thrombus in STEMI is associated with adverse outcomes. However, routine thrombus aspiration failed to demonstrate the anticipated benefit. Hence, management of high coronary thrombus burden remains challenging. We sought to assess for the first time extracted thrombotic material characteristics utilizing micro-computed tomography (micro-CT).Methods: One hundred thirteen STEMI patients undergoing thrombus aspiration were enrolled. Micro-CT was undertaken to quantify retrieved thrombus volume, surface, and density. Correlation of these indices with angiographic and electrocardiographic outcomes was performed.Results: Mean aspirated thrombus volume, surface, and density (±standard deviation) were 15.71 ± 20.10 mm3, 302.89 ± 692.54 mm2, and 3139.04 ± 901.88 Hounsfield units, respectively. Aspirated volume and surface were significantly higher (p < 0.001) in patients with higher angiographic thrombus burden. After multivariable analysis, independent predictors for thrombus volume were reference vessel diameter (RVD) (p = 0.011), right coronary artery (RCA) (p = 0.039), and smoking (p = 0.027), whereas RVD (p = 0.018) and RCA (p = 0.019) were predictive for thrombus surface. Thrombus volume and surface were independently associated with distal embolization (p = 0.007 and p = 0.028, respectively), no-reflow phenomenon (p = 0.002 and p = 0.006, respectively), and angiographically evident residual thrombus (p = 0.007 and p = 0.002, respectively). Higher thrombus density was correlated with worse pre-procedural TIMI flow (p < 0.001). Patients with higher aspirated volume and surface developed less ST resolution (p = 0.042 and p = 0.023, respectively).Conclusions: Angiographic outcomes linked with worse prognosis were more frequent among patients with larger extracted thrombus. Despite retrieving larger thrombus load in these patients, current thrombectomy devices fail to deal with thrombotic material adequately. Further studies of novel thrombus aspiration technologies are warranted to improve patient outcomes.Clinical Trial Registration: QUEST-STEMI trial ClinicalTrials.gov number: NCT03429608 Date of registration: February 12, 2018. The study was prospectively registered.

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568 Imaging and quantitative estimation of thrombus burden in patients with ST elevation acute myocardial infarction (STEMI) with the use of micro-computed tomography-A methodological approach

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jez319.298 ◽

2020 ◽

Vol 21 (Supplement_1) ◽

Author(s):

E Karagiannidis ◽

N V Konstantinidis ◽

G Sofidis ◽

E Chatzinikolaou ◽

G Sianos

Keyword(s):

Myocardial Infarction ◽

Computed Tomography ◽

Acute Myocardial Infarction ◽

Clinical Outcomes ◽

Quantitative Estimation ◽

Adverse Outcomes ◽

Micro Ct ◽

Thrombus Aspiration ◽

Micro Computed Tomography ◽

St Elevation

Abstract Funding Acknowledgements Operational Program "Human Resources Development, Education and Lifelong Learning" - co-financed by the European Social Fund and Greek national funds Background Acute myocardial infarction with ST elevation (STEMI) remains one of the leading causes of mortality. High thrombus burden has been proven to be an independent risk factor for stent thrombosis and for Major Adverse Clinical outcomes. However randomized controlled trials concerning thrombus aspiration showed controversial results, providing no evidence of benefits for thrombus aspiration. A possible explanation is that aspiration was performed as a routine strategy, whereas these patients should be considered as a heterogeneous group and they should be risk-stratified. Thus, it is important to classify patients according to the volume of thrombus burden. The currently existing classifications of thrombus burden are based on visual assessment of angiographic characteristics and they are not reflecting the volume of the thrombi in actual numbers. To the best of our knowledge, never before has the exact volume of thrombus burden been quantified. Purpose The study aims to assess for the first time, through the application of innovative technologies (micro-Computed Tomography, micro-CT), important characteristics of aspirated thrombi (volume and density), which might be linked to certain clinical outcomes, in patients with STEMI. Methodology After being aspirated, thrombi are preserved in formalin. As they consist of soft tissue with low X-ray absorption, thrombi have to be stained using contrast enhancing chemicals prior to scanning; in particular a solution containing 0.3% phosphotungstic acid is used (Metscher protocol). The scanning procedure results into a series of projection images arranged in the form of image stacks which, in turn, are reformed in sections with the use of special software, which applies a modified algorithm of backward projection Feldkamp. The resulting sections are combined to create the 3D models which are further analyzed to extract useful measurements for the characteristics of the thrombi, such as volume and density. Results From January 2018 to May 2019, 66 patients were enrolled in the study. Mean age was 60.36 (±11.71) years and the majority of them (78.7%) were men. Revascularization was achieved in mean 358 ± 255 minutes from symptom onset. Distal embolization was observed in 27.5% of the patients and no-reflow phenomenon was seen in 11.6%. Angiographically evident residual thrombus burden was observed in 6 patients (8.7%). Micro-CT managed to effectively quantify the volume and the density of aspirated thrombi. Mean volume was 12.98 ± 10.84 mm3, mean density was 2992 ± 872 HU and mean surface was 0.206 ± 0.19. Conclusion Micro-CT can be used as a tool to effectively assess important characteristics of aspirated thrombi, which might be linked to certain clinical outcomes. This method could become the gold standard for the exact measurement of thrombus burden and could be used in larger, clinically-oriented trials to help stratify patients with thrombus burden according to their risk for adverse outcomes. Abstract 568 Figure. Coronary thrombi as depicted on micro-CT

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Observation of the Pulp Chamber of Maxillary First Premolars: A Micro-computed Tomographic Study

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405615666191016125937 ◽

2020 ◽

Vol 16 (3) ◽

pp. 224-230

Author(s):

Gozde Serindere ◽

Ceren Aktuna Belgin ◽

Kaan Orhan

Keyword(s):

Root Canal ◽

Age Groups ◽

Slice Thickness ◽

Micro Ct ◽

Micro Computed Tomography ◽

Pulp Chamber ◽

Anatomical Structures ◽

Computed Tomographic ◽

The Mean ◽

Chamber Floor

Background: There are a few studies about the evaluation of maxillary first premolars internal structure with micro-computed tomography (micro-CT). The aim of this study was to assess morphological features of the pulp chamber in maxillary first premolar teeth using micro- CT. Methods: Extracted 15 maxillary first premolar teeth were selected from the patients who were in different age groups. The distance between the pulp orifices, the diameter of the pulp and the width of the pulp chamber floor were measured on the micro-CT images with the slice thickness of 13.6 µm. The number of root canal orifices and the presence of isthmus were evaluated. Results: The mean diameter of orifices was 0.73 mm on the buccal side while it was 0.61 mm on palatinal side. The mean distance between pulp orifices was 2.84 mm. The mean angle between pulp orifices was -21.53°. The mean height of pulp orifices on the buccal side was 4.32 mm while the mean height of pulp orifices on the palatinal side was 3.56 mm. The most observed shape of root canal orifices was flattened ribbon. No isthmus was found in specimens. Conclusion: Minor anatomical structures can be evaluated in more detail with micro-CT. The observation of the pulp cavity was analyzed using micro-CT.

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Micro-Computed Tomography Analysis of Subchondral Bone Regeneration Using Osteochondral Scaffolds in an Ovine Condyle Model

Applied Sciences ◽

10.3390/app11030891 ◽

2021 ◽

Vol 11 (3) ◽

pp. 891

Author(s):

Taylor Flaherty ◽

Maryam Tamaddon ◽

Chaozong Liu

Keyword(s):

Computed Tomography ◽

Bone Regeneration ◽

Subchondral Bone ◽

Volume Ratio ◽

Bone Volume ◽

Osteochondral Defects ◽

Micro Ct ◽

Micro Computed Tomography ◽

Trabecular Thickness ◽

Osteochondral Scaffold

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.

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Prognostic value of D-dimer for adverse outcomes in patients with infective endocarditis: an observational study

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-02078-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ying-Wen Lin ◽

Mei Jiang ◽

Xue-biao Wei ◽

Jie-leng Huang ◽

Zedazhong Su ◽

...

Keyword(s):

Regression Analysis ◽

Infective Endocarditis ◽

Adverse Events ◽

Prognostic Value ◽

Multivariable Analysis ◽

Adverse Outcomes ◽

Hospital Death ◽

Large Sample Size ◽

Cox Regression Analysis ◽

D Dimer

Abstract Background Increased D-dimer levels have been shown to correlate with adverse outcomes in various clinical conditions. However, few studies with a large sample size have been performed thus far to evaluate the prognostic value of D-dimer in patients with infective endocarditis (IE). Methods 613 patients with IE were included in the study and categorized into two groups according to the cut-off of D-dimer determined by receiver operating characteristic (ROC) curve analysis for in-hospital death: > 3.5 mg/L (n = 89) and ≤ 3.5 mg/L (n = 524). Multivariable regression analysis was used to determine the association of D-dimer with in-hospital adverse events and six-month death. Results In-hospital death (22.5% vs. 7.3%), embolism (33.7% vs 18.2%), and stroke (29.2% vs 15.8%) were significantly higher in patients with D-dimer > 3.5 mg/L than in those with D-dimer ≤ 3.5 mg/L. Multivariable analysis showed that D-dimer was an independent risk factor for in-hospital adverse events (odds ratio = 1.11, 95% CI 1.03–1.19, P = 0.005). In addition, the Kaplan–Meier curve showed that the cumulative 6-month mortality was significantly higher in patients with D-dimer > 3.5 mg/L than in those with D-dimer ≤ 3.5 mg/L (log-rank test = 39.19, P < 0.0001). Multivariable Cox regression analysis showed that D-dimer remained a significant predictor for six-month death (HR 1.11, 95% CI 1.05–1.18, P < 0.001). Conclusions D-dimer is a reliable prognostic biomarker that independently associated with in-hospital adverse events and six-month mortality in patients with IE.

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Additive-manufactured Ti-6Al-4 V/Polyetheretherketone composite porous cage for Interbody fusion: bone growth and biocompatibility evaluation in a porcine model

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04022-0 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Pei-I Tsai ◽

Meng-Huang Wu ◽

Yen-Yao Li ◽

Tzu-Hung Lin ◽

Jane S. C. Tsai ◽

...

Keyword(s):

Bone Formation ◽

Bone Growth ◽

Lumbar Fusion ◽

High Porosity ◽

Ti Alloy ◽

Micro Ct ◽

Micro Computed Tomography ◽

Intervertebral Fusion ◽

Porous Ti ◽

Peek Composite

Abstract Background We developed a porous Ti alloy/PEEK composite interbody cage by utilizing the advantages of polyetheretherketone (PEEK) and titanium alloy (Ti alloy) in combination with additive manufacturing technology. Methods Porous Ti alloy/PEEK composite cages were manufactured using various controlled porosities. Anterior intervertebral lumbar fusion and posterior augmentation were performed at three vertebral levels on 20 female pigs. Each level was randomly implanted with one of the five cages that were tested: a commercialized pure PEEK cage, a Ti alloy/PEEK composite cage with nonporous Ti alloy endplates, and three composite cages with porosities of 40, 60, and 80%, respectively. Micro-computed tomography (CT), backscattered-electron SEM (BSE-SEM), and histological analyses were performed. Results Micro-CT and histological analyses revealed improved bone growth in high-porosity groups. Micro-CT and BSE-SEM demonstrated that structures with high porosities, especially 60 and 80%, facilitated more bone formation inside the implant but not outside the implant. Histological analysis also showed that bone formation was higher in Ti alloy groups than in the PEEK group. Conclusion The composite cage presents the biological advantages of Ti alloy porous endplates and the mechanical and radiographic advantages of the PEEK central core, which makes it suitable for use as a single implant for intervertebral fusion.

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Using micro-computed tomography to reveal the anatomy of adult Diaphorina citri Kuwayama (Insecta: Hemiptera, Liviidae) and how it pierces and feeds within a citrus leaf

Scientific Reports ◽

10.1038/s41598-020-80404-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Javier Alba-Tercedor ◽

Wayne B. Hunter ◽

Ignacio Alba-Alejandre

Keyword(s):

Computed Tomography ◽

Significant Advance ◽

Micro Ct ◽

Diaphorina Citri ◽

Ct Reconstruction ◽

Internal Anatomy ◽

Micro Computed Tomography ◽

Citrus Leaf ◽

Teaching Aids ◽

Adult Feeding

AbstractThe Asian citrus psyllid (ACP), Diaphorina citri, is a harmful pest of citrus trees that transmits Candidatus Liberibacter spp. which causes Huanglongbing (HLB) (citrus greening disease); this is considered to be the most serious bacterial disease of citrus plants. Here we detail an anatomical study of the external and internal anatomy (excluding the reproductive system) using micro-computed tomography (micro-CT). This is the first complete 3D micro-CT reconstruction of the anatomy of a psylloid insect and includes a 3D reconstruction of an adult feeding on a citrus leaf that can be used on mobile devices. Detailed rendered images and videos support first descriptions of coxal and scapus antennal glands and sexual differences in the internal anatomy (hindgut rectum, mesothoracic ganglion and brain). This represents a significant advance in our knowledge of ACP anatomy, and of psyllids in general. Together the images, videos and 3D model constitute a unique anatomical atlas and are useful tools for future research and as teaching aids.

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ST-Elevation Myocardial Infarction and COVID-19 Pneumonia: The Importance of Risk-Stratification of Myocardial Injury in COVID-19 Era

Indian Journal of Clinical Cardiology ◽

10.1177/2632463621992389 ◽

2021 ◽

pp. 263246362199238

Author(s):

Julio C. Sauza-Sosa ◽

Oscar Millan-Iturbe ◽

Jorge Mendoza-Ramirez ◽

Carlos N. Velazquez-Gutierrez ◽

Erika Lizeth De la Cruz Reyna ◽

...

Keyword(s):

Risk Stratification ◽

Injury Risk ◽

Myocardial Injury ◽

Cardiovascular Complications ◽

Adverse Outcomes ◽

St Elevation ◽

Diagnostic Coronary Angiography ◽

Serial Measurements ◽

Initial Classification

Background: Myocardial injury is a common manifestation in patients with coronavirus disease (COVID-19), and the correlation with adverse outcomes has been demonstrated; therefore, adequate monitoring of myocardial injury markers is very important. Case Summary: A patient with COVID-19 was hospitalized in our hospital with an initial classification of intermediate risk for myocardial injury, after serial measurements of myocardial injury markers, risk was readjusted to high, as shown later by electrocardiographic abnormalities. The patient underwent emergency diagnostic coronary angiography and successful angioplasty. The patient was discharged to home. Discussion: Myocardial injury risk-stratification is essential in patients with COVID-19, since it is essential in the recognition of patients who are susceptible to cardiovascular complications.

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A Micro-Computed Tomography Comparison of the Porosity in Additively Fabricated CuCr1 Alloy Parts Using Virgin and Surface-Modified Powders

Materials ◽

10.3390/ma14081995 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1995

Author(s):

Mirko Sinico ◽

Suraj Dinkar Jadhav ◽

Ann Witvrouw ◽

Kim Vanmeensel ◽

Wim Dewulf

Keyword(s):

High Energy ◽

High Energy Density ◽

Micro Ct ◽

Micro Computed Tomography ◽

Powder Bed ◽

Metallurgical Defects ◽

Ct Analysis ◽

Ct Data ◽

Surface Modified ◽

Fusion Pores

Recently, the use of novel CuCr1 surface-modified powder for reliable laser powder-bed fusion (LPBF) manufacturing has been proposed, enabling a broader LPBF processing window and longer powder storage life. Nevertheless, virgin CuCr1 powder is also LPBF processable, on the condition that a high-energy density is employed. In this work, we compare two dense specimens produced from virgin and surface-modified CuCr1 powder. Furthermore, a third sample fabricated from surface-modified powder is characterized to understand an abnormal porosity content initially detected through Archimedes testing. Utilizing high-resolution micro-CT scans, the nature of the defects present in the different samples is revealed. Pores are analyzed in terms of size, morphology and spatial distribution. The micro-CT data reveal that the virgin CuCr1 dense specimen displays keyhole pores plus pit cavities spanning multiple layer thicknesses. On the other hand, the sample fabricated with the surface-modified CuCr1 powder mainly contains small and spherical equi-distributed metallurgical defects. Finally, the CT analysis of the third specimen reveals the presence of a W contamination, favoring lack-of-fusion pores between subsequent LPBF layers. The LPBF melting mode (keyhole or conductive), the properties of the material, and the potential presence of contaminants are connected to the different porosity types and discussed.

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Effects of pre-extraction intermittent PTH administration on extraction socket healing in bisphosphonate administered ovariectomized rats

Scientific Reports ◽

10.1038/s41598-020-79787-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jae-Young Kim ◽

Hyo-Won Jang ◽

Jung-In Kim ◽

In-Ho Cha

Keyword(s):

Tooth Extraction ◽

Bisphosphonate Therapy ◽

Ovariectomized Rats ◽

Control Group ◽

Micro Ct ◽

Micro Computed Tomography ◽

Extraction Socket ◽

Before And After ◽

Socket Healing ◽

Positive Effect

AbstractThe purpose of this study was to investigate the effect of administering intermittent parathyroid hormone (iPTH) before tooth extraction versus after tooth extraction on the risk of developing MRONJ in experimental animal model. Twenty-five ovariectomized rats received 6 weeks of bisphosphonate therapy. They were classified into 3 groups, based on the timing of the medication, as Control, Pre-PTH and Post-PTH groups. For Control group, normal saline was administered before and after tooth extraction. iPTH was administered during 4 weeks before tooth extraction for Pre-PTH group and after tooth extraction for Post-PTH group. The animals were euthanized 8 weeks after tooth extraction. Macroscopic, histological, micro-computed tomography (micro-CT), and histomorphometric examinations were conducted. The incidences of impaired healing were 11.11% both in Pre-PTH and Post-PTH groups, which was lower than the Control group (42.86%). Bone healing in the extraction socket, based on micro-CT and histomorphometry evaluations, was best in Post-PTH and worst in Control group. The Pre-PTH group showed moderate healing pattern. Despite of limitations in this study, the authors identified Pre-PTH group seems to have positive effect on extraction socket healing. With regard to timing, administering iPTH after tooth extraction was superior to applying it before tooth extraction.

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