Diagnosis of acute ischemia using dual energy CT after mechanical thrombectomy

2015 ◽  
Vol 8 (10) ◽  
pp. 996-1000 ◽  
Author(s):  
Joanna Gariani ◽  
Victor Cuvinciuc ◽  
Delphine Courvoisier ◽  
Bernhard Krauss ◽  
Vitor Mendes Pereira ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Mechanical Thrombectomy ◽  
Dual Energy ◽  
Institutional Review Board ◽  
Dual Energy Ct ◽  
Acute Ischemia ◽  
Weighted Sum ◽  
Unenhanced Ct ◽  
Institutional Review ◽  
Contrast Ct

Background and purposeTo assess the performance of dual energy unenhanced CT in the detection of acute ischemia after mechanical thrombectomy.MethodsRetrospective study, approved by the local institutional review board, including all patients that underwent intra-arterial thrombectomy in our institution over a period of 2 years. The presence of acute ischemia and hemorrhage was evaluated by three readers. Sensitivity and specificity of the non-contrast CT weighted sum image (NCCT) and the virtual non-contrast reconstructed image (VNC) were estimated and compared using generalized estimating equations to account for the non-independence of regions in each patient.Results58 patients (27 women and 31 men; mean age 70.4 years) were included in the study, yielding 580 regions of interest. Sensitivity and specificity in detecting acute ischemia were higher for all readers when using VNC, with a significant increase in sensitivity for two readers (p<0.001 and 0.01) and a significant increase in specificity in one reader (p<0.001). Specificity in detecting hemorrhage was excellent for all readers.ConclusionsDual energy unenhanced CT VNC images were superior in the identification of acute ischemia in comparison with NCCT.

Characterization of Subarachnoid Hyperdensities After Thrombectomy for Acute Stroke Using Dual-Energy CT

Neurology ◽  
2021 ◽  
pp. 10.1212/WNL.0000000000013198
Author(s):  
Arturo Renú ◽  
Carlos Laredo ◽  
Alejandro Rodríguez-Vázquez ◽  
Daniel Santana ◽  
Mariano Werner ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Acute Stroke ◽  
Mechanical Thrombectomy ◽  
Dual Energy ◽  
Common Finding ◽  
Dual Energy Ct ◽  
Consecutive Series ◽  
Contrast Extravasation ◽  
Logistic Regression Models ◽  
Increased Risk

Background and Objectives:The presence of post-interventional subarachnoid hyperdensities (SA-HD) is a relatively common finding after mechanical thrombectomy (MT). We aimed to assess the incidence, characteristics, clinical relevance and predictors of SA-HD after MT as categorized through the use of post-interventional Dual Energy-CT (DE-CT).Methods:A single-center consecutive series of acute stroke patients treated with MT were retrospectively reviewed. Post-treatment SA-HD were defined as incident extra-axial hyperdensities in a follow-up DE-CT performed within a median of 8 hours after MT. SA-HD were further classified according to their content (isolated contrast extravasation versus blood extravasation) and extension [diffuse (hyperdensities in more than one extraparenchymal compartments) versus non-diffuse]. Adjusted logistic regression models assessed the association of SA-HD with pretreatment and procedural variables and with bad clinical outcome (shift towards worse categories in the ordinal Rankin Scale at 90 days).Results:SA-HD were observed in 120 (28%) of the 424 included patients (isolated contrast extravasation n=22, blood extravasation n=98). In this group, SA-HD were diffuse in 72 (60%) patients (isolated contrast extravasation n=7, blood extravasation n=65) and non-diffuse in 48 (40%) patients (isolated contrast extravasation n=15, blood extravasation n=33). Diffuse SA-HD were significantly associated with worse clinical outcome in adjusted models (cOR=2.3, 95%CI=1.36-4.00, p=0.002), unlike the specific SA-HD content alone. In contrast with the absence of SA-HD, only the diffuse pattern with blood extravasation was significantly associated with worse clinical outcome (cOR=2.4, 95%CI=1.36-4.15, p=0.002). Diffuse SA-HD patterns were predicted by M2 occlusions, more thrombectomy passes and concurrent parenchymal hematomas.Discussion:In our cohort of patients imaged within a median of 8 hours after MT, post-interventional SA-HD showed a diffuse pattern in 17% of thrombectomies and were associated with more arduous procedures. Diffuse SA-HD but not local collections of blood or contrast extravasations were associated with an increased risk of poor outcome and death. These findings reinforce the need for improvement in reperfusion strategies.Classification of Evidence:This study provides Class II evidence that in individuals with proximal carotid artery territory occlusions treated with mechanical thrombectomy, diffuse post-interventional subarachnoid hyperdensities on imaging 8 hours post-procedure are associated with worse clinical outcomes at 90 days.

scholarly journals Virtual Non-Contrast Dual-Energy CT Reconstructions More Accurately Estimate Core Infarct Volume Over Conventional Non-Contrast CT

2020 ◽  
Author(s):  
Dylan N. Wolman ◽  
Fasco van Ommen ◽  
Elizabeth Tong ◽  
Frans Kauw ◽  
Lior Molvin ◽  
...  
Keyword(s):  
Infarct Volume ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Contrast Ct ◽  
Core Infarct

scholarly journals A prospective study of dual-energy CT in determining the metastatic and non-metastatic lymph nodes of colorectal cancer

2020 ◽  
Author(s):  
Lin Qiu ◽  
Junjiao Hu ◽  
Zeping Weng ◽  
Fasheng Li ◽  
Fei Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Lymph Nodes ◽  
Electron Density ◽  
Sensitivity And Specificity ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Metastatic Node ◽  
Metastatic Lymph Nodes ◽  
Quantitative Parameters ◽  
Metastatic Lymph

Abstract Background To explore the ability of Dual-energy CT (DECT) to differentiate metastatic from non-metastatic lymph nodes in colorectal cancer (CRC). Methods Seventy-one patients with primary CRC underwent contrast-enhanced DECT imaging before surgery. The colorectal specimen was scanned after surgery, and lymph nodes were matched to the pathology report. The DECT quantitative parameters were analyzed: dual-energy curve slope value(λHU), standardized iodine concentration (n△HU), iodine water ratio (nIWR), electron density value (nρeff), and effective atom-number (nZ), for the metastatic and non-metastatic lymph node differentiation. Also, sensitivity and specificity analyses were performed by using receiver operating characteristic curve. Results One hundred and fifty lymph nodes including 66 non-metastatic and 84 metastatic lymph nodes were matched using the radiological-pathological correlation. Metastatic node had a significantly greater λHU, n△HU and nIWR values than non-metastatic node in both arterial and venous phases (P < 0.01). The AUC, sensitivity and specificity were 0.80, 80.30% and 65.48% for λHU; 0.86, 69.70% and 95.24% for n△HU; 0.88, 71.21% and 95.24% for nIWR in the arterial phase. No significant difference was found in electron density and effective Z value for differentiation. Conclusion Dual-energy CT quantitative parameters may be helpful in diagnosing metastatic lymph nodes of CRC.

scholarly journals The diagnostic performance of dual energy CT for diagnosing gout: a systematic literature review and meta-analysis

Rheumatology ◽  
2019 ◽  
Vol 58 (12) ◽  
pp. 2117-2121 ◽  
Author(s):  
Mihaela Gamala ◽  
Johannes W G Jacobs ◽  
Jaap M van Laar
Keyword(s):  
Diagnostic Accuracy ◽  
Sensitivity And Specificity ◽  
Meta Analysis ◽  
Dual Energy ◽  
Disease Stage ◽  
Cochrane Library ◽  
Dual Energy Ct ◽  
Recent Onset ◽  
Short Disease Duration ◽  
Library Studies

Abstract Objective This study aimed to assess the utility of dual energy CT (DECT) for diagnosing gout. Methods A systematic literature search was performed in PubMed, EMBASE and Cochrane Library. Studies evaluating the utility of DECT for diagnosing gout were included. Reference standards were detection of monosodium urate crystals at SF assessment or a validated set of criteria. The methodological quality of studies was evaluated according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 criteria. Data from person-based and joint-/localization-based evaluations were pooled separately, and subgroup analyses for disease stage/duration and reference standard were performed. Results Ten studies were included; in person-based evaluations, the pooled (95% CI) sensitivity and specificity were 0.81 (0.77, 0.86) and 0.91 (0.85, 0.95), respectively. In joint-based evaluations, they were 0.83 (0.79, 0.86) and 0.88 (0.83, 0.92), respectively. At short disease duration (⩽6 weeks), the pooled (95% CI) sensitivity and specificity at the joint level were 0.55 (0.46, 0.64) and 0.89 (0.84, 0.94), respectively. Conclusion DECT has a high diagnostic accuracy in established gout, but its diagnostic sensitivity is low in subjects with recent onset gout.

scholarly journals Feasibility of using post-contrast dual-energy CT for pediatric radiation treatment planning and dose calculation

2020 ◽  
pp. 20200170
Author(s):  
Ozgur Ates ◽  
Chia-ho Hua ◽  
Li Zhao ◽  
Nadav Shapira ◽  
Yoad Yagil ◽  
...  
Keyword(s):  
Proton Therapy ◽  
Dose Calculation ◽  
Iodine Concentration ◽  
Dual Energy ◽  
Conventional Approach ◽  
Dual Energy Ct ◽  
Post Contrast ◽  
Dose Distributions ◽  
Iodinated Contrast ◽  
Contrast Ct

Objectives: When iodinated contrast is administered during CT simulation, standard practice requires a separate non-contrast CT for dose calculation. The objective of this study is to validate our hypothesis that since iodine affects Hounsfield units (HUs) more than electron density (ED), the information from post-contrast dual-layer CT (DLCT) would be sufficient for accurate dose calculation for both photon and proton therapy. Methods and materials: 10 pediatric patients with abdominal tumors underwent DLCT scans before and after iodinated contrast administration for radiotherapy planning. Dose distributions with these DLCT-based methods were compared to those with conventional calibration-curve methods that map HU images to ED and stopping-power ratio (SPR) images. Results: For photon plans, conventional and DLCT approaches based on post-contrast scans underestimated the PTV D99 by 0.87 ± 0.70% (p = 0.18) and 0.36 ± 0.31% (p = 0.34), respectively, comparing to their non-contrast optimization plans. Renal iodine concentration was weakly associated with D99 deviation for both conventional (R2 = 0.10) and DLCT (R2 = 0.02) approaches. For proton plans, the clinical target volume D99 errors were 3.67 ± 2.43% (p = 0.0001) and 0.30 ± 0.25% (p = 0.40) for conventional and DLCT approaches, respectively. The proton beam range changed noticeably with the conventional approach. Renal iodine concentration was highly associated with D99 deviation for the conventional approach (R2 = 0.83) but not for DLCT (R2 = 0.007). Conclusion: Conventional CT with iodine contrast resulted in a large dosimetric error for proton therapy, compared to true non-contrast plans, but the error was less for photon therapy. These errors can be greatly reduced in the case of the proton plans if DLCT is used, raising the possibility of using only a single post-contrast CT for radiotherapy dose calculation, thus reducing the time and imaging dose required. Advances in knowledge: This study is the first to compare directly the differences in the calculated dose distributions between pre- and post-contrast CT images generated by single-energy CT and dual-energy CT methods for photon and proton therapy.

Sign in / Sign up

Export Citation Format

Share Document