Comparison between conventional CT and grayscale inversion CT images in the assessment of the post-operative spinal orthopaedic implants

Background and Purpose: Ischemic brain edema can be measured in computed tomography (CT) using quantitative net water uptake (NWU), a recently established imaging biomarker. NWU determined in follow-up CT after mechanical thrombectomy (MT) has shown to be a strong predictor of functional outcome. However, disruption of the blood–brain barrier after MT may also lead to contrast staining, increasing the density on CT scans, and hence, directly impairing measurements of NWU. The purpose of this study was to determine whether dual-energy dual-layer CT (DDCT) after MT can improve the quantification of NWU by measuring NWU in conventional polychromatic CT images (CP-I) and virtual non-contrast images (VNC-I). We hypothesized that VNC-based NWU (vNWU) differs from NWU in conventional CT (cNWU).Methods: Ten patients with middle cerebral artery occlusion who received a DDCT follow-up scan after MT were included. NWU was quantified in conventional and VNC images as previously published and was compared using paired sample t-tests.Results: The mean cNWU was 3.3% (95%CI: 0–0.41%), and vNWU was 11% (95%CI: 1.3–23.4), which was not statistically different (p = 0.09). Two patients showed significant differences between cNWU and vNWU (Δ = 24% and Δ = 36%), while the agreement of cNWU/vNWU in 8/10 patients was high (difference 2.3%, p = 0.23).Conclusion: NWU may be quantified precisely on conventional CT images, as the underestimation of ischemic edema due to contrast staining was low. However, a proportion of patients after MT might show significant contrast leakage resulting in edema underestimation. Further research is needed to validate these findings and investigate clinical implications.

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Functional respiratory imaging provides novel insights into the long-term respiratory sequelae of bronchopulmonary dysplasia

European Respiratory Journal ◽

10.1183/13993003.02110-2020 ◽

2020 ◽

pp. 2002110

Author(s):

Kristien Vanhaverbeke ◽

Monique Slaats ◽

Mohammed Al-Nejar ◽

Niek Everaars ◽

Annemiek Snoeckx ◽

...

Keyword(s):

Preterm Birth ◽

Lung Function ◽

Bronchopulmonary Dysplasia ◽

Functional Assessment ◽

Airway Resistance ◽

Ct Images ◽

Air Trapping ◽

Distal Airway ◽

Conventional Ct

RationaleBronchopulmonary dysplasia (BPD) is a common complication of preterm birth. Lung function and imaging are classically used to assess BPD. Functional Respiratory Imaging (FRI) combines a structural and functional assessment of the airways and their vasculature. We aimed to assess BPD with FRI and to correlate these findings with the clinical presentation.MethodsWe included 37 adolescents with a history of preterm birth (22 BPD cases and 15 preterm controls). The study protocol included a detailed history, lung function testing and CT (at TLC and FRC) with FRI. CT images were also assessed using the Aukland scoring system.ResultsBPD patients had lower FEV1/FVC (p=0.02) and impaired diffusion capacity (p=0.02).Aukland CT scores were not different between the two groups. FRI analysis showed higher lobar volumes in BPD patients at FRC (p<0.01) but not at TLC. Airway resistance was significantly higher in the BPD group, especially in the distal airways. Additionally, FRI showed more air trapping in BPD patients, in contrast to findings on conventional CT images.ConclusionThis study is the first to use FRI in research for BPD. FRI analysis showed higher lobar volumes in BPD patients, indicating air trapping and reduced inspiratory capacity. In contrast to Aukland CT scores, FRI showed more air trapping in the BPD group, suggesting that FRI might be a more sensitive detection method. Importantly, we also showed increased distal airway resistance in BPD patients. By combining structural and functional assessment, FRI may help to better understand the long-term sequelae of BPD.

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Radiomics analysis of multicenter CT images for discriminating mucinous adenocarcinoma from nomucinous adenocarcinoma in rectal cancer and comparison with conventional CT values

Journal of X-Ray Science and Technology ◽

10.3233/xst-190614 ◽

2020 ◽

Vol 28 (2) ◽

pp. 285-297 ◽

Cited By ~ 2

Author(s):

Yu-xi Ge ◽

Jie Li ◽

Jun-qin Zhang ◽

Shao-feng Duan ◽

Yan-kui Liu ◽

...

Keyword(s):

Rectal Cancer ◽

Mucinous Adenocarcinoma ◽

Ct Images ◽

Conventional Ct

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Optimized Backprojection Filtration Algorithm for Postoperative Reduction and Analysis of Respiratory Infection-Related Factors of Pelvic Fractures by CT Imaging

Scientific Programming ◽

10.1155/2021/3554718 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Aihua Pu ◽

Hua Wang ◽

Jichong Ying

Keyword(s):

Pelvic Fracture ◽

Ct Images ◽

Ct Imaging ◽

Pelvic Fractures ◽

Conventional Group ◽

Ct Image ◽

Diagnosis Group ◽

Imaging Characteristics ◽

Conventional Ct ◽

Projection Filtering

To explore the computed tomography (CT) imaging characteristics and BPF algorithm fine lung CT image efficiency for the diagnosis of pelvic fracture patients and assist clinicians to carry out the disease care and treatment, CT images based on optimized back-projection filtering (BPF) algorithm were utilized to diagnose postoperative reduction of pelvic fractures and penetrating lung infection caused by long-term bed rest. A total of 100 patients with pelvic fracture were selected and all of them underwent pelvic fracture surgery and were rolled into conventional CT diagnosis group (conventional group) and BPF algorithm optimized CT image diagnosis group (BPF group). One group used conventional CT images to guide pelvic reduction and detect lung infections, and the other used BPF algorithm to optimize the images. The results showed that the BPF group was superior to the conventional CT group in both image clarity and shadow area, and the peak signal-to-noise ratio (PSNR) was significantly better than that of the conventional group ( P < 0.05 ). Nine more cases were detected in the algorithm group than in the conventional group, and the incidence of complications was 48% in the conventional group and 28% in the BPF group, with a statistical difference of 20% between the two groups ( P < 0.05 ). In addition, the satisfaction of returning patients was 96% in the BPF group and 77% in the conventional group ( P < 0.05 ). The diagnosis of pulmonary infection was more obvious in the BPF group, indicating that BPF optimization of the CT image was suitable for clinical diagnosis and had a practical application value.

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“Conventional” CT images from spectral measurements

10.1117/12.2216988 ◽

2016 ◽

Cited By ~ 2

Author(s):

Paurakh L. Rajbhandary ◽

Norbert J. Pelc

Keyword(s):

Ct Images ◽

Spectral Measurements ◽

Conventional Ct

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Improved Diagnostic Accuracy of Bone Metastasis Detection by Water-HAP Associated to Non-Contrast CT

Diagnostics ◽

10.3390/diagnostics10100853 ◽

2020 ◽

Vol 10 (10) ◽

pp. 853

Author(s):

Yoshinobu Ishiwata ◽

Yojiro Hieda ◽

Soichiro Kaki ◽

Shinjiro Aso ◽

Keiichi Horie ◽

...

Keyword(s):

Bone Metastasis ◽

Diagnostic Accuracy ◽

Predictive Value ◽

Ct Images ◽

Kappa Coefficient ◽

Characteristic Analysis ◽

Predictive Values ◽

Contrast Ct ◽

Sensitivity Specificity ◽

Conventional Ct

We examined whether water-hydroxyapatite (HAP) images improve the diagnostic accuracy of bone metastasis compared with non-contrast CT alone. We retrospectively evaluated dual-energy computed tomography (DECT) images of 83 cancer patients (bone metastasis, 31; without bone metastasis, 52) from May 2018 to June 2019. Initially, two evaluators examined for bone metastasis on conventional CT images. In the second session, both CT and CT images plus water-HAP images on DECT. The confidence of bone metastasis was scored from 1 (benign) to 5 (malignant). The sensitivity, specificity, positive predictive values, and negative predictive values for both modalities were calculated based on true positive and negative findings. The intra-observer area under curve (AUC) for detecting bone metastasis was compared by receiver operating characteristic analysis. Kappa coefficient calculated the inter-observer agreement. In conventional CT images, sensitivity, specificity, positive predictive value, and negative predictive value of raters 1 and 2 for the identification of bone metastases were 0.742 and 0.710, 0.981 and 0.981, 0.958 and 0.957, and 0.864 and 0.850, respectively. In water-HAP, they were 1.00 and 1.00, 0.981 and 1.00, 0.969 and 1.00, and 1.00 and 1.00, respectively. In CT, AUCs were 0.861 and 0.845 in each observer. On water-HAP images, AUCs were 0.990 and 1.00. Kappa coefficient was 0.964 for CT and 0.976 for water-HAP images. The combination of CT and water-HAP images significantly increased diagnostic accuracy for detecting bone metastasis. Water-HAP images on DECT may enable accurate initial staging, reduced radiation exposure, and cost.

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Virtual monoenergetic images from spectral detector CT as a surrogate for conventional CT images: Unaltered attenuation characteristics with reduced image noise

European Journal of Radiology ◽

10.1016/j.ejrad.2019.05.019 ◽

2019 ◽

Vol 117 ◽

pp. 49-55 ◽

Cited By ~ 7

Author(s):

Nils Große Hokamp ◽

R. Gilkeson ◽

M.K. Jordan ◽

K.R. Laukamp ◽

Victor-Frederick Neuhaus ◽

...

Keyword(s):

Ct Images ◽

Image Noise ◽

Spectral Detector Ct ◽

Virtual Monoenergetic Images ◽

Conventional Ct ◽

Attenuation Characteristics ◽

Monoenergetic Images

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Quantitative and qualitative assessment of plasma cell dyscrasias in dual-layer spectral CT

European Radiology ◽

10.1007/s00330-021-07821-0 ◽

2021 ◽

Author(s):

S. C. Brandelik ◽

S. Skornitzke ◽

T. Mokry ◽

S. Sauer ◽

W. Stiller ◽

...

Keyword(s):

Bone Marrow ◽

Plasma Cell ◽

Ct Images ◽

Bone Marrow Infiltration ◽

Quantitative Detection ◽

Spectral Ct ◽

Diffuse Infiltration ◽

Plasma Cell Dyscrasias ◽

Vertebral Bodies ◽

Conventional Ct

Abstract Objectives Virtual non-calcium (VNCa) images could improve assessment of plasma cell dyscrasias by enhancing visibility of bone marrow. Thus, VNCa images from dual-layer spectral CT (DLCT) were evaluated at different calcium suppression (CaSupp) indices, correlating results with apparent diffusion coefficient (ADC) values from MRI. Methods Thirty-two patients with initial clinical diagnosis of a plasma cell dyscrasia before any chemotherapeutic treatment, who had undergone whole-body low-dose DLCT and MRI within 2 months, were retrospectively enrolled. VNCa images with CaSupp indices ranging from 25 to 95 in steps of 10, conventional CT images, and ADC maps were quantitatively analyzed using region-of-interests in the vertebral bodies C7, T12, L1-L5, and the iliac bone. Independent two-sample t-test, Wilcoxon-signed-rank test, Pearson’s correlation, and ROC analysis were performed. Results Eighteen patients had a non-diffuse, 14 a diffuse infiltration in conventional MRI. A significant difference between diffuse and non-diffuse infiltration was shown for VNCa-CT with CaSupp indices from 55 to 95, for conventional CT, and for ADC (each p < 0.0001). Significant quantitative correlation between VNCa-CT and MRI could be found with strongest correlation at CaSupp index 65 for L3 (r = 0.68, p < 0.0001) and averaged L1-L5 (r = 0.66, p < 0.0001). The optimum CT number cut-off point for differentiation between diffuse and non-diffuse infiltration at CaSupp index 65 for averaged L1-L5 was −1.6 HU (sensitivity 78.6%, specificity 75.0%). Conclusion Measurements in VNCa-CT showed the highest correlation with ADC at CaSupp index 65. VNCa technique may prove useful for evaluation of bone marrow infiltration if MRI is not feasible. Key Points • VNCa-CT images can support the evaluation of bone marrow infiltration in plasma cell dyscrasias. • VNCa measurements of vertebral bodies show significant correlation with ADC in MRI. • Averaging L1-L5 at CaSupp index 65 allowed quantitative detection of infiltration comparable to MRI ADC.

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