Search results for " computed tomography"
showing 10 items of 411 documents
Cardiac Computed Tomography Angiography Follow-Up of Resorbable Magnesium Scaffolds.
2021
Abstract Introduction An ancillary advantage of bioresorbable scaffolds is the possibility of non-invasive imaging assessment of the treated coronary segment. Cardiac computed tomography angiography (CCTA) studies of resorbable magnesium scaffolds (RMS) are scarce. Methods In this collaborative, international study, nine patients who had an RMS implanted underwent CCTA as part of follow-up assessment. Core-lab blinded quantitative and qualitative assessment was performed by an independent CCTA investigator. Results Eight studies were amenable for quantitative analysis, and the blinded CT investigator successfully located and evaluated patency of RMS in all cases. The CCTA follow-up in-scaff…
Contribution of thallium-201-SPECT to the grading of tumorous alterations of the brain
1992
Single photon emission computed tomography (SPECT) with thallium-201-chloride (201Tl) was used in 22 patients to assess the grade of malignancy of brain tumors. Low- and high-grade malignant gliomas could be well differentiated by calculating the Grade Index (GI), i.e., 201Tl uptake in the tumor area relative to a contralateral brain region. Low-grade gliomas (WHO-grade I-II) usually showed a GI of1.5. Tumors classified histologically as high-grade malignant (WHO-grade III-IV) had GI values greater than 1.42 and a mean value of 1.89. Until labelled amino-acid tracers for gamma-cameras become commercially available, thallium-201 brain-SPECT can provide an independent and complementary method…
Whole-body MRI, FDG-PET/CT, and bone marrow biopsy, for the assessment of bone marrow involvement in patients with newly diagnosed lymphoma.
2016
To compare whole-body MRI (WB-MRI) with diffusion-weighted imaging (DWI), FDG-PET/CT, and bone marrow biopsy (BMB), for the evaluation of bone marrow involvement (BMI) in patients with newly diagnosed lymphoma.This retrospective study was approved by our Institutional Review Board. Two independent radiologists and one nuclear medicine specialist reviewed all WB-MRI and FDG-PET/CT scans prospectively performed on 104 patients with newly diagnosed lymphoma (53 males; 47 Hodgkin; mean age: 44 years; range, 15-86 years) between 2013 and 2015. The delay between imaging scans and BMBs was up to 10 days. The diagnostic accuracy of WB-MRI (1.5 Tesla MR scanner, with T1w, T2w-STIR, and DWI sequences…
Volume stability of hydroxyapatite and β-tricalcium phosphate biphasic bone graft material in maxillary sinus floor elevation: a radiographic study u…
2015
Objectives The purpose of this study was to confirm volume stability of biphasic calcium phosphate (BCP) through the changes of grafted volume over the time by 3D CT analyzing software program. Patients and Methods Fifteen patients, 16 sinuses who were scheduled a staged implantation through sinus floor elevation (SFE)–lateral window technique from 2009 to 2011 were included in the study. Of the 15 patients, eight were male and seven were female (mean age 50.1). For sinus floor augmentation, BCP with local blood was packed loosely into the maxillary sinus and the grafted site was covered with a collagen membrane. For the evaluation of volume change, 3D CBCT scans were taken five times at pr…
A new 3D method for measuring cranio-facial relationships with cone beam computed tomography (CBCT)
2013
Objectives: CBCT systems, with their high precision 3D reconstructions, 1:1 images and accuracy in locating cephalometric landmarks, allows us to evaluate measurements from craniofacial structures, so enabling us to replace the anthropometric methods or bidimensional methods used until now. The aims are to analyse cranio-facial relationships in a sample of patients who had previously undergone a CBCT and create a new 3D cephalometric method for assessing and measuring patients. Study Design: 90 patients who had a CBCT (i-Cat®) as a diagnostic register were selected. 12 cephalometric landmarks on the three spatial planes (X,Y,Z) were defined and 21 linear measurements were established. Using…
Dynamic image denoising for voxel-wise quantification with Statistical Parametric Mapping in molecular neuroimaging.
2018
Purpose PET and SPECT voxel kinetics are highly noised. To our knowledge, no study has determined the effect of denoising on the ability to detect differences in binding at the voxel level using Statistical Parametric Mapping (SPM). Methods In the present study, groups of subject-images with a 10%- and 20%- difference in binding of [123I]iomazenil (IMZ) were simulated. They were denoised with Factor Analysis (FA). Parametric images of binding potential (BPND) were produced with the simplified reference tissue model (SRTM) and the Logan non-invasive graphical analysis (LNIGA) and analyzed using SPM to detect group differences. FA was also applied to [123I]IMZ and [11C]flumazenil (FMZ) clinic…
Loading modalities and bone structures at nonweight-bearing upper extremity and weight-bearing lower extremity: a pQCT study of adult female athletes.
2005
This cross-sectional study of adult female athletes assessed whether the apparent loading-related differences in bone structure are primarily associated with the loading type or the muscle performance-related joint moments. Several structural variables at shaft sites of the tibia, radius and humerus, and distal sites of the tibia and radius were measured with peripheral quantitative computed tomography (pQCT) among 113 female national level athletes (representing hurdling, volleyball, soccer, racket-sports and swimming) and their 30 nonathletic referents. For the weight-bearing lower extremities, the loading modalities of the above sports were classified into high-impact (hurdling, volleyba…
HRCT and scleroderma: semiquantitative evaluation of lung damage and functional abnormalities.
2007
This study sought to validate the Warrick score in the assessment of lung involvement in systemic sclerosis (SSc) and correlate the results with functional abnormalities. In addition, we propose the use of high resolution computed tomography (HRCT) indices of alveolitis and fibrosis to discriminate between different stages of the disease.Thirty-one patients with SSc (16 with the diffuse form and 15 with the limited form) underwent functional and HRCT evaluations of the lung. The semiquantitative evaluation of radiological involvement, as proposed by Warrick, provides a score for each lesion based on the severity and the extent of the pulmonary damage. In addition to the total score, indices…
Potential clinical value of quantitative fluorine-18-fluorodeoxyglucose-PET/computed tomography using a graph-based method analysis in evaluation of …
2019
Objectives To identify the clinical relevance of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with 18F-FDG PET/CT and to assess the potential benefit of using semiquantitative PET measures to discern malignant from benign lesions. Methods Forty-one patients who underwent F-FDG PET/CT scans during the oncologic follow-up, revealing abnormal incidental 18F-FDG accumulations in the GIT were included in this retrospective analysis. Incidental PET/CT findings were correlated with endoscopic and histological findings. Semiquantitative PET values (SUVmax, SUVmean, SULpeak, and TLG) were evaluated by using a new graph-based method. Two sample t-test analysis has been per…
A semi-automatic approach for epicardial adipose tissue segmentation and quantification on cardiac CT scans
2019
Abstract Many studies have shown that epicardial fat is associated with a higher risk of heart diseases. Accurate epicardial adipose tissue quantification is still an open research issue. Considering that manual approaches are generally user-dependent and time-consuming, computer-assisted tools can considerably improve the result repeatability as well as reduce the time required for performing an accurate segmentation. Unfortunately, fully automatic strategies might not always identify the Region of Interest (ROI) correctly. Moreover, they could require user interaction for handling unexpected events. This paper proposes a semi-automatic method for Epicardial Fat Volume (EFV) segmentation a…