scholarly journals Image Patch-Based Net Water Uptake and Radiomics Models Predict Malignant Cerebral Edema After Ischemic Stroke

2020 ◽  
Vol 11 ◽  
Author(s):  
Bowen Fu ◽  
Shouliang Qi ◽  
Lin Tao ◽  
Haibin Xu ◽  
Yan Kang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Water Uptake ◽  
Cerebral Edema ◽  
Intraclass Correlation ◽  
Ct Images ◽  
Imaging Features ◽  
Lesion Segmentation ◽  
Image Patch ◽  
Ischemic Lesion ◽  
Significant Difference

Malignant cerebral edema (MCE) after an ischemic stroke results in a poor outcome or death. Early prediction of MCE helps to identify subjects that could benefit from a surgical decompressive craniectomy. Net water uptake (NWU) in an ischemic lesion is a predictor of MCE; however, CT perfusion and lesion segmentation are required. This paper proposes a new Image Patch-based Net Water Uptake (IP-NWU) procedure that only uses non-enhanced admission CT and does not need lesion segmentation. IP-NWU is calculated by comparing the density of ischemic and contralateral normal patches selected from the middle cerebral artery (MCA) area using standard reference images. We also compared IP-NWU with the Segmented Region-based NWU (SR-NWU) procedure in which segmented ischemic regions from follow-up CT images are overlaid onto admission images. Furthermore, IP-NWU and its combination with imaging features are used to construct predictive models of MCE with a radiomics approach. In total, 116 patients with an MCA infarction (39 with MCE and 77 without MCE) were included in the study. IP-NWU was significantly higher for patients with MCE than those without MCE (p < 0.05). IP-NWU can predict MCE with an AUC of 0.86. There was no significant difference between IP-NWU and SR-NWU, nor between their predictive efficacy for MCE. The inter-reader and interoperation agreement of IP-NWU was exceptional according to the Intraclass Correlation Coefficient (ICC) analysis (inter-reader: ICC = 0.92; interoperation: ICC = 0.95). By combining IP-NWU with imaging features through a random forest classifier, the radiomics model achieved the highest AUC (0.96). In summary, IP-NWU and radiomics models that combine IP-NWU with imaging features can precisely predict MCE using only admission non-enhanced CT images scanned within 24 h from onset.

scholarly journals Evaluation of the Usefulness of CO-RADS for Chest CT in Patients Suspected of Having COVID-19

Diagnostics ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 608 ◽  
Author(s):  
Tomoyuki Fujioka ◽  
Marie Takahashi ◽  
Mio Mori ◽  
Junichi Tsuchiya ◽  
Emi Yamaga ◽  
...  
Keyword(s):  
Interobserver Agreement ◽  
Characteristic Curve ◽  
Intraclass Correlation ◽  
Ct Images ◽  
Chest Ct ◽  
Rt Pcr ◽  
Radiological Society ◽  
Significant Difference ◽  
The Individual ◽  
Sensitivity Specificity

The purpose of this study was to use the Coronavirus Disease 2019 (COVID-19) Reporting and Data System (CO-RADS) to evaluate the chest computed tomography (CT) images of patients suspected of having COVID-19, and to investigate its diagnostic performance and interobserver agreement. The Dutch Radiological Society developed CO-RADS as a diagnostic indicator for assessing suspicion of lung involvement of COVID-19 on a scale of 1 (very low) to 5 (very high). We investigated retrospectively 154 adult patients with clinically suspected COVID-19, between April and June 2020, who underwent chest CT and reverse transcription-polymerase chain reaction (RT-PCR). The patients’ average age was 61.3 years (range, 21–93), 101 were male, and 76 were RT-PCR positive. Using CO-RADS, four radiologists evaluated the chest CT images. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated. Interobserver agreement was calculated using the intraclass correlation coefficient (ICC) by comparing the individual reader’s score to the median of the remaining three radiologists. The average sensitivity was 87.8% (range, 80.2–93.4%), specificity was 66.4% (range, 51.3–84.5%), and AUC was 0.859 (range, 0.847–0.881); there was no significant difference between the readers (p > 0.200). In 325 (52.8%) of 616 observations, there was absolute agreement among observers. The average ICC of readers was 0.840 (range, 0.800–0.874; p < 0.001). CO-RADS is a categorical taxonomic evaluation scheme for COVID-19 pneumonia, using chest CT images, that provides outstanding performance and from substantial to almost perfect interobserver agreement for predicting COVID-19.

Abstract W MP18: NCCT ASPECTS Underestimates Infarct Core in Early Presenters with Poor Collateral Status

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Jun-Gyu Yang ◽  
Jeong-Ho Hong ◽  
Chang-Hyun Kim ◽  
Hyuk-Won Chang ◽  
Bijoy K Menon ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
National Institutes Of Health ◽  
Multivariable Logistic Regression Analysis ◽  
Infarct Core ◽  
Anterior Circulation ◽  
Ischemic Lesion ◽  
Ischemic Change ◽  
Significant Difference ◽  
Noncontrast Ct ◽  
Occlusion Of Ica

Background and Purpose: Noncontrast CT (NCCT) identifies early ischemic change that can predict irreversible ischemic injury. However DWI is more sensitive than NCCT in detection of early ischemic lesion. Our aim was to investigate the factors that influence discrepancy in early ischemic change detection between CT and DWI among good NCCT scan. Methods: We collected consecutive 167 ischemic stroke patients with occlusion of ICA and/or MCA M1 diagnosed by CTA and DWI within 6h of onset (last seen normal, LNT) between August 2004 and February 2013. Alberta Stroke Program Early Computed Tomography Score (ASPECTS) was used to evaluate discrepancy between lesions on NCCT and DWI MR. We identified 109 patients with a good NCCT scan defined as ASPECTS 6-10. Discrepancy between NCCT and DWI was when DWI ASPECTS was 0-5 and no discrepancy was when DWI ASPECTS was 6-10. Regional leptomeningeal collateral (rLMC) score by CTA was used to evaluate collateral status. Results: We reviewed 109 patients (mean age 67.5 ± 12.5 years) with median baseline National Institutes of Health Stroke Scale (NIHSS) 14 (interquartile range, 10-19). Discrepancy group (N=40, 36.7%) had shorter time from LNT to CT (median 98 vs 132 min, p=0.013), higher score of initial NIHSS (median 17 vs 13, p=0.013), lower rLMC score (median 10.5 vs 14, p<0.001). There was no significant difference from CT to DWI time (median 41 vs 40 min) between both groups. In a multivariable logistic regression analysis, time from LNT to CT (OR 0.99; 95% CI 0.99-1.00; P=0.05), rLMC score (OR 0.21; 95% CI 0.08-0.56; P=0.002) were independently associated with the discrepancy group. Conclusion: Discrepancy between CT and DWI is common in patients with acute anterior circulation ischemic stroke. This discrepancy is more apparent when patients present early and have poor collaterals.

scholarly journals The Role of Edema in Subacute Lesion Progression After Treatment of Acute Ischemic Stroke

2021 ◽  
Vol 12 ◽  
Author(s):  
Praneeta Konduri ◽  
Katinka van Kranendonk ◽  
Anna Boers ◽  
Kilian Treurniet ◽  
Olvert Berkhemer ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Functional Outcome ◽  
Water Uptake ◽  
Infarct Volume ◽  
Lesion Volume ◽  
Ischemic Lesion ◽  
Contrast Ct ◽  
Mr Clean

Background: Ischemic lesions commonly continue to progress even days after treatment, and this lesion growth is associated with unfavorable functional outcome in acute ischemic stroke patients. The aim of this study is to elucidate the role of edema in subacute lesion progression and its influence on unfavorable functional outcome by quantifying net water uptake.Methods: We included all 187 patients from the MR CLEAN trial who had high quality follow-up non-contrast CT at 24 h and 1 week. Using a CT densitometry-based method to calculate the net water uptake, we differentiated total ischemic lesion volume (TILV) into edema volume (EV) and edema-corrected infarct volume (ecIV). We calculated these volumes at 24 h and 1 week after stroke and determined their progression in the subacute period. We assessed the effect of 24-h lesion characteristics on EV and ecIV progression. We evaluated the influence of edema and edema-corrected infarct progression on favorable functional outcome after 90 days (modified Rankin Scale: 0–2) after correcting for potential confounders. Lastly, we compared these volumes between subgroups of patients with and without successful recanalization using the Mann–Whitney U-test.Results: Median TILV increased from 37 (IQR: 18–81) ml to 68 (IQR: 30–130) ml between 24 h and 1 week after stroke, while the net water uptake increased from 22 (IQR: 16–26)% to 27 (IQR: 22–32)%. The TILV progression of 20 (8.8–40) ml was mostly caused by ecIV with a median increase of 12 (2.4–21) ml vs. 6.5 (2.7–15) ml of EV progression. Larger TILV, EV, and ecIV volumes at 24 h were all associated with more edema and lesion progression. Edema progression was associated with unfavorable functional outcome [aOR: 0.53 (0.28–0.94) per 10 ml; p-value: 0.05], while edema-corrected infarct progression showed a similar, non-significant association [aOR: 0.80 (0.62–0.99); p-value: 0.06]. Lastly, edema progression was larger in patients without successful recanalization, whereas ecIV progression was comparable between the subgroups.Conclusion: EV increases in evolving ischemic lesions in the period between 1 day and 1 week after acute ischemic stroke. This progression is larger in patients without successful recanalization and is associated with unfavorable functional outcome. However, the extent of edema cannot explain the total expansion of ischemic lesions since edema-corrected infarct progression is larger than the edema progression.

scholarly journals Correlation between CT images of lateral plateau and lateral meniscus injuries in patients with Schatzker II tibial plateau fractures:a retrospective study

2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Ying Pu ◽  
Zhu Lei ◽  
Ding Wenge ◽  
Xu Yue ◽  
Jiang Xiaowei ◽  
...  
Keyword(s):  
Tibial Plateau ◽  
Arthroscopic Surgery ◽  
Intraclass Correlation ◽  
Lateral Meniscus ◽  
Ct Images ◽  
Posterior Horn ◽  
Meniscus Injury ◽  
Significant Difference ◽  
Lateral Plateau ◽  
Meniscus Injuries

Abstract Background There is a great deal of controversy on whether routine MRI examination is needed for fresh fractures while the vast majority of patients with tibial plateau fractures (TPFs) receive preoperative X-ray and CT examinations. The purpose of the study was to analyze the exact correlation between CT images of lateral plateau and lateral meniscus injuries in Schatzker II TPFs. Methods A total of 296 patients with Schatzker II TPFs from August 2012 to January 2021 in two trauma centers were enrolled for the analysis. According to the actual situation during open reduction internal fixation (ORIF) and knee arthroscopic surgery, patients were divided into meniscus injury (including rupture, incarceration, etc.) and non-meniscus injury groups. The values of both lateral plateau depression (LPD) and lateral plateau widening (LPW) of lateral tibial plateau on CT images were measured, and their correlation with lateral meniscus injury was then analyzed. The relevant receiver operating characteristic (ROC) curve was drawn to evaluate the optimal cut-off point of the two indicators which could predict meniscus injury. Results The intra- and inter-observer reliabilities of LPD and LPW were acceptable (intraclass correlation coefficient (ICC) > 0.8). The average LPD was 13.2 ± 3.2 mm while the average value of the group without meniscus injury was 9.4 ± 3.2 mm. The difference between the two groups was statistically significant (P < 0.05). The average LPW was 8.0 ± 1.4 mm and 6.8 ± 1.6 mm in meniscus injury and non-meniscus injury groups with a significant difference (P < 0.05). The optimal predictive cut-off value of LPD and LPW was 7.9 mm (sensitivity-95.0%, specificity-58.8%, area under the curve (AUC-0.818) and 7.5 mm (sensitivity-70.0%, specificity - 70.6%, AUC - 0.724), respectively. The meniscus injury group mainly showed injuries involving the mid-body and posterior horn of lateral meniscus (98.1%, 157/160). Conclusions The mid-body and posterior horn of lateral meniscus injury is more likely to occur in patients with Schatzker II TPFs when LPD > 7.9 mm and/or LPW > 7.5 mm on CT. These findings will definitely provide guidance for orthopedic surgeons in treating such injuries. During the operation, more attention is required be paid to the treatment of the meniscus and the possible fracture reduction difficulties and poor alignment caused by meniscus rupture and incarceration should be fully considered in order to achieve better surgical results.

scholarly journals Perfusion imaging-based tissue-level collaterals predict ischemic lesion net water uptake in patients with acute ischemic stroke and large vessel occlusion

2021 ◽  
pp. 0271678X2199220
Author(s):  
Tobias D Faizy ◽  
Reza Kabiri ◽  
Soren Christensen ◽  
Michael Mlynash ◽  
Gabriella Kuraitis ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Functional Outcome ◽  
Water Uptake ◽  
Tissue Level ◽  
Large Vessel ◽  
Large Vessel Occlusion ◽  
Vessel Occlusion ◽  
Ischemic Lesion ◽  
Good Functional Outcome

Ischemic lesion Net Water Uptake (NWU) quantifies cerebral edema formation and likely correlates with the microvascular perfusion status of patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO). We hypothesized that favorable tissue-level collaterals (TLC) predict less NWU and good functional outcomes. We performed a retrospective multicenter analysis of AIS-LVO patients who underwent thrombectomy triage. TLC were measured on cerebral perfusion studies using the hypoperfusion intensity ratio (HIR; volume ratio of brain tissue with [Tmax > 10 sec/Tmax > 6 sec]); favorable TLC were regarded as HIR [Formula: see text] 0.4. NWU was determined using a quantitative densitometry approach on follow-up CT. Primary outcome was NWU. Secondary outcome was a good functional outcome (modified Rankin Scale [mRS] 0–2). 580 patients met inclusion criteria. Favorable TLC ( β: 4.23, SE: 0.65; p < 0.001) predicted smaller NWU after treatment. Favorable TLC (OR: 2.35, [95% CI: 1.31–4.21]; p < 0.001), and decreased NWU (OR: 0.75, [95% CI: 0.70–0.79]; p < 0.001) predicted good functional outcome, while controlling for age, glucose, CTA collaterals, baseline NIHSS and good vessel reperfusion status. We conclude that favorable TLC predict less ischemic lesion NWU after treatment in AIS-LVO patients. Favorable TLC and decreased NWU were independent predictors of good functional outcome.

Liver Elastography in Healthy Children Using Three Different Systems – How Many Measurements Are Necessary?

2020 ◽  
Author(s):  
Anders Batman Mjelle ◽  
Anesa Mulabecirovic ◽  
Roald Flesland Havre ◽  
Edda Jonina Olafsdottir ◽  
Odd Helge Gilja ◽  
...  
Keyword(s):  
Shear Wave ◽  
Transient Elastography ◽  
Intraclass Correlation ◽  
Age Groups ◽  
Liver Stiffness ◽  
Shear Wave Elastography ◽  
Healthy Children ◽  
Significant Difference ◽  
Pediatric Liver Disease ◽  
Liver Elastography

Abstract Purpose Liver elastography is increasingly being applied in screening for and follow-up of pediatric liver disease, and has been shown to correlate well with fibrosis staging through liver biopsy. Because time is of the essence when examining children, we wanted to evaluate if a reliable result can be achieved with fewer acquisitions. Materials and Methods 243 healthy children aged 4–17 years were examined after three hours of fasting. Participants were divided into four age groups: 4–7 years; 8–11 years; 12–14 years and 15–17 years. Both two-dimensional shear wave elastography (2D-SWE; GE Logiq E9) and point shear wave elastography (pSWE; Samsung RS80A with Prestige) were performed in all participants, while transient elastography (TE, Fibroscan) was performed in a subset of 87 children aged 8–17 years. Median liver stiffness measurement (LSM) values of 3, 4, 5, 6, 7, and 8 acquisitions were compared with the median value of 10 acquisitions (reference standard). Comparison was performed for all participants together as well as within every specific age group. We investigated both the intraclass correlation coefficient (ICC) with absolute agreement and all outliers more than 10 %, 20 % or ≥ 0.5 or 1.0 kPa from the median of 10 acquisitions. Results For all three systems there was no significant difference between three and ten acquisitions, with ICCs ≥ 0.97. All systems needed 4 acquisitions to achieve no LSM deviating ≥ 1.0 kPa of a median of ten. To achieve no LSM deviating ≥ 20 % of a median of ten acquisitions, pSWE and TE needed 4 acquisitions, while 2D-SWE required 6 acquisitions. Conclusion Our results contradict recommendations of 10 acquisitions for pSWE and TE and only 3 for 2D-SWE.

Characterization of Ischemic Stroke in CT Images using Image Processing

2017 ◽  
Vol 7 (9) ◽  
pp. 18
Author(s):  
Amal Alzain ◽  
Suhaib Alameen ◽  
Rani Elmaki ◽  
Mohamed E. M. Gar-Elnabi
Keyword(s):  
Ischemic Stroke ◽  
White Matter ◽  
Classification Accuracy ◽  
Ct Images ◽  
Gray Level ◽  
Level Variation ◽  
Interactive Data ◽  
The Brain ◽  
Brain Tissues

This study concern to characterize the brain tissues to ischemic stroke, gray matter, white matter and CSF using texture analysisto extract classification features from CT images. The First Order Statistic techniques included sevenfeatures. To find the gray level variation in CT images it complements the FOS features extracted from CT images withgray level in pixels and estimate the variation of thesubpatterns. analyzing the image with Interactive Data Language IDL software to measure the grey level of images. The results show that the Gray Level variation and   features give classification accuracy of ischemic stroke 97.6%, gray matter95.2%, white matter 97.3% and the CSF classification accuracy 98.0%. The overall classification accuracy of brain tissues 97.0%.These relationships are stored in a Texture Dictionary that can be later used to automatically annotate new CT images with the appropriate brain tissues names.

scholarly journals The The Effectiveness of Early Mobilization Time on Balance and Functional Ability after Ischemic Stroke

2019 ◽  
Vol 7 (7) ◽  
pp. 1088-1092
Author(s):  
Umi Budi Rahayu ◽  
Samekto Wibowo ◽  
Ismail Setyopranoto
Keyword(s):  
Randomized Controlled Trial ◽  
Ischemic Stroke ◽  
Functional Ability ◽  
Controlled Trial ◽  
Early Mobilization ◽  
Berg Balance Scale ◽  
Early Mobilisation ◽  
Inclusion Criteria ◽  
Randomized Controlled ◽  
Significant Difference

BACKGROUND: Early mobilisation (EM) after-ischemic stroke is a motor learning intervention aimed to restore nerve cells and to improve balance and functional ability. Unfortunately, the study of when this intervention began has not been widely studied. AIM: On this study was compared the effect of EM started at 24 hours and 48 hours after an ischemic stroke on balance and functional ability. MATERIAL AND METHODS: Randomized controlled trial involving 40 patients on 2 groups meeting predefined inclusion criteria. The levels of balance were measured using the Berg Balance Scale, and the functional ability was measured using the Barthel Index, at 5th and 7th day. RESULTS: A significant difference was observed in both balance (p = 0.038) and functional ability (p = 0.021) obtained on the 7th day of assessment between both groups. A significant difference on the 5th day was observed only in the functional ability (p = 0.002) and not in the balance (p = 0.147), between the groups. CONCLUSION: EM started at 24 hours after the ischemic stroke has been found to have a better impact on balance and functional ability compared to that at 48 hours.

Predictive value of time-variant color-coded multiphase CT angiography (mCTA) regarding clinical outcome of acute ischemic stroke: in comparison with conventional mCTA and CT perfusion

2020 ◽  
pp. 028418512098177
Author(s):  
Yu Lin ◽  
Nannan Kang ◽  
Jianghe Kang ◽  
Shaomao Lv ◽  
Jinan Wang
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Predictive Value ◽  
Ct Perfusion ◽  
Roc Curves ◽  
Multivariate Logistic Regression Model ◽  
Infarct Core ◽  
Predictive Values ◽  
Significant Difference ◽  
Core Volume

Background Color-coded multiphase computed tomography angiography (mCTA) can provide time-variant blood flow information of collateral circulation for acute ischemic stroke (AIS). Purpose To compare the predictive values of color-coded mCTA, conventional mCTA, and CT perfusion (CTP) for the clinical outcomes of patients with AIS. Material and Methods Consecutive patients with anterior circulation AIS were retrospectively reviewed at our center. Baseline collateral scores of color-coded mCTA and conventional mCTA were assessed by a 6-point scale. The reliabilities between junior and senior observers were assessed by weighted Kappa coefficients. Receiver operating characteristic (ROC) curves and multivariate logistic regression model were applied to evaluate the predictive capabilities of color-coded mCTA and conventional mCTA scores, and CTP parameters (hypoperfusion and infarct core volume) for a favorable outcome of AIS. Results A total of 138 patients (including 70 cases of good outcomes) were included in our study. Patients with favorable prognoses were correlated with better collateral circulations on both color-coded and conventional mCTA, and smaller hypoperfusion and infarct core volume (all P < 0.05) on CTP. ROC curves revealed no significant difference between the predictive capability of color-coded and conventional mCTA ( P = 0.427). The predictive value of CTP parameters tended to be inferior to that of color-coded mCTA score (all P < 0.001). Both junior and senior observers had consistently excellent performances (κ = 0.89) when analyzing color-coded mCTA maps. Conclusion Color-coded mCTA provides prognostic information of patients with AIS equivalent to or better than that of conventional mCTA and CTP. Junior radiologists can reach high diagnostic accuracy when interpreting color-coded mCTA images.

scholarly journals Computing infection distributions and longitudinal evolution patterns in lung CT images

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Dongdong Gu ◽  
Liyun Chen ◽  
Fei Shan ◽  
Liming Xia ◽  
Jun Liu ◽  
...  
Keyword(s):  
Time Course ◽  
Lower Lobe ◽  
Ground Truth ◽  
Distribution Patterns ◽  
Lung Infection ◽  
Ct Images ◽  
Community Acquired Pneumonia ◽  
Disease Course ◽  
Distribution Maps ◽  
Significant Difference

Abstract Background Spatial and temporal lung infection distributions of coronavirus disease 2019 (COVID-19) and their changes could reveal important patterns to better understand the disease and its time course. This paper presents a pipeline to analyze statistically these patterns by automatically segmenting the infection regions and registering them onto a common template. Methods A VB-Net is designed to automatically segment infection regions in CT images. After training and validating the model, we segmented all the CT images in the study. The segmentation results are then warped onto a pre-defined template CT image using deformable registration based on lung fields. Then, the spatial distributions of infection regions and those during the course of the disease are calculated at the voxel level. Visualization and quantitative comparison can be performed between different groups. We compared the distribution maps between COVID-19 and community acquired pneumonia (CAP), between severe and critical COVID-19, and across the time course of the disease. Results For the performance of infection segmentation, comparing the segmentation results with manually annotated ground-truth, the average Dice is 91.6% ± 10.0%, which is close to the inter-rater difference between two radiologists (the Dice is 96.1% ± 3.5%). The distribution map of infection regions shows that high probability regions are in the peripheral subpleural (up to 35.1% in probability). COVID-19 GGO lesions are more widely spread than consolidations, and the latter are located more peripherally. Onset images of severe COVID-19 (inpatients) show similar lesion distributions but with smaller areas of significant difference in the right lower lobe compared to critical COVID-19 (intensive care unit patients). About the disease course, critical COVID-19 patients showed four subsequent patterns (progression, absorption, enlargement, and further absorption) in our collected dataset, with remarkable concurrent HU patterns for GGO and consolidations. Conclusions By segmenting the infection regions with a VB-Net and registering all the CT images and the segmentation results onto a template, spatial distribution patterns of infections can be computed automatically. The algorithm provides an effective tool to visualize and quantify the spatial patterns of lung infection diseases and their changes during the disease course. Our results demonstrate different patterns between COVID-19 and CAP, between severe and critical COVID-19, as well as four subsequent disease course patterns of the severe COVID-19 patients studied, with remarkable concurrent HU patterns for GGO and consolidations.

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