scholarly journals Contrast-Enhanced Magnetic Resonance Imaging with Magnetic Transfer Effect in Differential Diagnosis of Hemangiomas and Metastases of Liver

2017 ◽  
pp. 20-28
Author(s):  
M. Yu. Sannikov ◽  
O. Yu. Borodin ◽  
A. A. Ermakova ◽  
A. A. Kolotushkina
Keyword(s):  
Differential Diagnosis ◽  
Liver Metastases ◽  
Sensitivity And Specificity ◽  
Paired Comparison ◽  
Magnetization Transfer ◽  
Contrast Ratio ◽  
Liver Lesion ◽  
Transfer Effect ◽  
Focal Liver Lesion ◽  
Focal Lesions

Objective: to investigate the operating characteristics of contrast MRI of the liver using magnetization transfer effect in the differential diagnosis of hemangiomas and metastatic lesions in comparison with dynamic contrast.Material and methods. The material of the study were dynamic contrast MRI images of 25 patients with diagnosis of direction of focal liver lesion. Inclusion criteria were detection of typical MR-semiotic for hemangioma (n = 10 to 40% of cases) or multiple liver metastases (n = 15 to 60% of cases).In the group with metastases exclusion criteria was the primary detection of obscure single focal lesions, as well as the diagnosis of other primary tumors, in particular cholangiocellular cancer (n = 1). All MRI studies were performed using MRI Toshiba Titan Octave with of 1.5 Tesla magnetic field. T1-weighted static contrast MRI investigation of liver performed after 3–5 minutes after a series of dynamic contrast MRI with modes: T1-FE-FSat and T1-TSEMTS (Δf = -210 Hz, FA = 600°). The magnevist at a dose of 0.1 mmol/kg was used as a contrast agent. Each focal liver lesion differentiated between hemangiomaand metastasis with the calculation of contrast ratio (CR) for each lesion. Statistical analysis of CR was performed using T-test and T-test Welch. The sensitivity and specificity parameters were compared during the ROC-analysis.Results. In our statistical analysis groups formed not from patients, because we were compared results about focal lesions of a liver referred to metastasis or hemangiomas. All the patients included in a research had focal lesions mostly multiple and in the comparative analysis of contrast ratio in the T1-FE-FSat and T1-TSE-MTC was carried out on 21 (20%) hemangiomas and 84 (80%) metastasises. The significant (p < 10–4) contrast enhancement using T1-TSE-MTS, as in the case of hemangiomas and in metastatic lesions relative to T1-FE-FSat revealed by comparing the CRs. No significant differences were found in the differentiation of hemangiomas and liver metastases in modes T1-FE-FSat and T1-TSE-MTS when paired comparison of ROC-curves (p > 0.18). No significant differences were found when paired comparison of CRs between hemangiomas in T1-FE-FSat mode and metastases in T1-TSEMTSimages (p > 0.8). An additive effect (sensitivity and specificity – 98.8% and 85.7%) occurs when we used to CRcomm=35.7% in T1-FE-FSat modes and T1-TSE-MTS.Conclusions. 1. Contrast MRI using magnetization transfer effect allows significantly increase the contrast of focal liver formations on the type of hemangiomas and metastases. 2. The achieved contrast level in 2D TSE images with magnetization transfer effect of liver metastatic foci corresponds to that of hemangiomas in 2D FE mode. 3. Maximum parameters of sensitivity and specificity in the differential diagnosis of hemangiomas and liver metastases obtained by using 2D-FE-FSat and 2D-TSE-MTC in post contrast phase.

scholarly journals Improving acute demyelinating lesion detection: which T1-weighted magnetic resonance acquisition is more sensitive to gadolinium enhancement?

2019 ◽  
Vol 77 (7) ◽  
pp. 485-492
Author(s):  
Lázaro Luiz Faria do AMARAL ◽  
Diego Cardoso FRAGOSO ◽  
Antonio José da ROCHA
Keyword(s):  
Single Dose ◽  
Magnetic Resonance ◽  
Spin Echo ◽  
Magnetization Transfer ◽  
Contrast Ratio ◽  
Accurate Method ◽  
Lesion Detection ◽  
Observer Agreement ◽  
Focal Lesions ◽  
Rapid Acquisition

ABSTRACT Because of the need for a standardized and accurate method for detecting multiple sclerosis (MS) inflammatory activity, different magnetic resonance (MR) acquisitions should be compared in order to choose the most sensitive sequence for clinical routine. Objective To compare the sensitivity of a T1-weighted image to a single dose of gadolinium (Gd) administration both with and without magnetization transfer to detect contrast enhancement in active demyelinating focal lesions. Methods A sample of relapsing-remitting MS patients were prospectively examined separately by two neuroradiologists using a 1.5 Tesla scanner. The outcome parameters were focused on Gd-enhancement detection attributed to acute demyelination. All MR examinations with at least one Gd-enhancing lesion were considered positive (MR+) and each lesion was analyzed according to its size and contrast ratio. Results Thirty-six MR examinations were analyzed with a high inter-observer agreement for MR+ detection (k coefficient > 0.8), which was excellent for the number of Gd-enhancing lesions (0.91 T1 spin-echo (SE), 0.88 T1 magnetization transfer contrast (MTC) sequence and 0.99 magnetization-prepared rapid acquisition with gradient-echo (MPRAGE). Significantly more MR+ were reported on the T1 MTC scans, followed by the T1 SE, and MPRAGE scans. Confidently, the T1 MTC sequence demonstrated higher accuracy in the detection of Gd-enhancing lesions, followed by the T1 SE and MPRAGE sequences. Further comparisons showed that there was a statistically significant increase in the contrast ratio and area of Gd-enhancement on the T1 MTC images when compared with both the SE and MPRAGE images. Conclusion Single-dose Gd T1 MTC sequence was confirmed to be the most sensitive acquisition for predicting inflammatory active lesions using a 1.5 T magnet in this sample of MS patients.

The value of preoperative computed tomography combined with ultrasound in the investigation of small indeterminate liver lesions in patients with colorectal cancer

2017 ◽  
Vol 58 (11) ◽  
pp. 1288-1293 ◽  
Author(s):  
Mirna Abraham-Nordling ◽  
Emma Öistämö ◽  
Thomas Josephson ◽  
Fredrik Hjern ◽  
Lennart Blomqvist
Keyword(s):  
Colorectal Cancer ◽  
Computed Tomography ◽  
Liver Metastases ◽  
Liver Lesion ◽  
Liver Cyst ◽  
Focal Liver Lesion ◽  
Focal Liver Lesions ◽  
Liver Lesions ◽  
Newly Diagnosed ◽  
Work Up

Background Computed tomography (CT) is used routinely for the preoperative detection of colorectal cancer (CRC) metastases. When small indeterminate focal liver lesions are detected that are too small to characterize (TSTC) on CT, additional imaging is usually needed, resulting in a potential delay in obtaining a complete diagnostic work-up. Purpose To determine the diagnostic accuracy of ultrasound (US) of the liver performed in direct conjunction to CT in the preoperative investigation among patients with newly diagnosed CRC when indeterminate liver lesions were found on CT. Material and Methods Preoperative investigations with CT and consecutive US where CT had shown at least one focal liver lesion in 74 patients diagnosed with CRC between June 2009 and February 2012 were retrospectively reviewed. Either histopathological findings or a combination of imaging and clinical follow-up one to three years after surgery was used as the reference. Results Liver metastases were diagnosed with CT/US in 13 out of 74 patients (17.6%). In one patient, a liver cyst was preoperatively regarded as liver metastasis by a combined CT/US. The sensitivity and specificity for the CT with consecutive US procedure was 100% (13/13) and 98.4% (60/61). Conclusion US performed in conjunction with CT in patients with indeterminate focal liver lesions on CT is an accurate work-up for detection of liver metastases in patients with newly diagnosed CRC. Although our results are promising, they cannot be considered safely generalizable to all hospitals.

scholarly journals The role of ultrasound in the differential diagnosis of liver tumors

2020 ◽  
pp. 35-42
Author(s):  
A. N. Katrich ◽  
S. V. Polshikov
Keyword(s):  
Differential Diagnosis ◽  
Liver Metastases ◽  
Liver Tumors ◽  
Spectral Characteristics ◽  
Liver Lesion ◽  
Contrast Enhanced ◽  
Number Of Patients ◽  
The Us ◽  
Diagnostic Capabilities ◽  
Specific Symptoms

Background. Liver lesions are increasingly found in a huge number of patients. Ultrasound (US) is the method of choice in liver lesion characterization. The limitations of traditional US techniques are well known. Multiparametric ultrasound (MPUS) includes multiple facets of the US examination, and their combination can significantly improve the diagnostic capabilities of the method.Objective. To evaluate the capabilities of MPUS in the differential diagnosis of liver tumors.Material and Methods. A retrospective analysis included 172 patients with morphologically confirmed liver tumors. All patients underwent an MPUS examination.Results. Traditional US techniques have a rather low specificity in the differential diagnosis of liver neoplasms: the sign of “contour clarity” was typical for hemangiomas, hepatocellular adenomas (HCA), liver metastases and was recorded in 82, 100, 96% cases, respectively; heterogeneous echostructure was noted in all nosological entities, groups of hepatocellular carcinomas (HCC), liver metastases and HCA were characterized by foci of various types of echogenicity. Specific symptoms were discovered in patients with liver metastases (32%) and focal nodular hyperplasia (FNH) (96%). Intratumoral blood flow was recorded in 34 (19.7%) cases. The study of spectral characteristics was possible only in 11 (6.4%) patients. Statistically significant differences in contrast-enhanced US parameters “contrasting onset in focus” were found between the groups “FNH & hemangioma” (р < 0.000046), “FNH & HCA” (р < 0.006293), “MTS & FNH” (р < 0.028125), “FNH & HCC” (р < 0.024933), “maximum fill-in time” – “FNH & hemangioma” (р < 0.012590), “FNH & HCC” (р < 0.007983), “MTS & HCC” (р < 0.000243). Statistically significant differences in the wash-out time were obtained in “MTS & HCC” and “MTS & HCA” groups.Conclusion. Conventional US should be used as basic screening, follow-up and navigation in the neoplastic biopsy. Contrast-enhanced US within MPUS is currently a well-established technique which allows a more precise and confident diagnosis of liver tumors.

Contrast-Enhanced MRI with Magnetization Transfer Effect in the Imaging of Brain Metastatic Lesions

2017 ◽  
pp. 8-17
Author(s):  
A. A. Ermakova ◽  
O. Yu. Borodin ◽  
M. Yu. Sannikov ◽  
S. D. Koval ◽  
V. Yu. Usov
Keyword(s):  
Comparative Analysis ◽  
Roc Analysis ◽  
Magnetization Transfer ◽  
Metastatic Lesion ◽  
Transfer Effect ◽  
Wilcoxon Test ◽  
Post Contrast ◽  
Metastatic Lesions ◽  
The Brain ◽  
Non Parametric

Purpose: to investigate the diagnostic opportunities of contrast  magnetic resonance imaging with the effect of magnetization transfer effect in the diagnosis of focal metastatic lesions in the brain.Materials and methods.Images of contrast MRI of the brain of 16  patients (mean age 49 ± 18.5 years) were analysed. Diagnosis of  the direction is focal brain lesion. All MRI studies were carried out  using the Toshiba Titan Octave with magnetic field of 1.5 T. The  contrast agent is “Magnevist” at concentration of 0.2 ml/kg was  used. After contrasting process two T1-weighted studies were  performed: without T1-SE magnetization transfer with parameters of pulse: TR = 540 ms, TE = 12 ms, DFOV = 24 sm, MX = 320 × 224  and with magnetization transfer – T1-SE-MTC with parameters of pulse: ΔF = −210 Hz, FA(МТС) = 600°, TR = 700 ms, TE = 10 ms,  DFOV = 23.9 sm, MX = 320 x 224. For each detected metastatic  lesion, a contrast-to-brain ratio (CBR) was calculated. Comparative  analysis of CBR values was carried out using a non-parametric  Wilcoxon test at a significance level p < 0.05. To evaluate the  sensitivity and specificity of the techniques in the detection of  metastatic foci (T1-SE and T1-SE-MTC), ROC analysis was used. The sample is divided into groups: 1 group is foci ≤5 mm in size, 2  group is foci from 6 to 10 mm, and 3 group is foci >10 mm. Results.Comparative analysis of CBR using non-parametric Wilcoxon test showed that the values of the CBR on T1-weighted  images with magnetization transfer are significantly higher (p  <0.001) that on T1-weighted images without magnetization transfer. According to the results of the ROC analysis, sensitivity in detecting  metastases (n = 90) in the brain on T1-SE-MTC and T1-SE was  91.7% and 81.6%, specificity was 100% and 97.6%, respectively.  The accuracy of the T1-SE-MTC is 10% higher in comparison with  the technique without magnetization transfer. Significant differences (p < 0.01) between the size of the foci detected in post-contrast T1- weighted images with magnetization transfer and in post-contrast  T1-weighted images without magnetization transfer, in particular for  foci ≤5 mm in size, were found. Conclusions1. Comparative analysis of CBR showed significant (p < 0.001)  increase of contrast between metastatic lesion and white matter on  T1-SE-MTC in comparison with T1-SE.2. The sensitivity, specificity and accuracy of the magnetization transfer program (T1-SE-MTC) in detecting foci of  metastatic lesions in the brain is significantly higher (p < 0.01), relative to T1-SE.3. The T1-SE-MTC program allows detecting more foci in comparison with T1-SE, in particular foci of ≤5 mm (96% and 86%, respectively, with p < 0.05).

Ultrasonic differential diagnostics of cyst and cystic tumors of the spleen

2020 ◽  
Vol 24 (3) ◽  
pp. 63-75
Author(s):  
Yu. A. Stepanova ◽  
M. Z. Alimurzaeva ◽  
D. A. Ionkin
Keyword(s):  
Differential Diagnosis ◽  
Cancer Metastasis ◽  
Malignant Tumors ◽  
Dynamic Control ◽  
Differential Diagnostics ◽  
Epithelial Lining ◽  
Focal Lesions ◽  
Morphological Form ◽  
Cystic Tumors ◽  
Number Of Patients

The incidence of focal lesions in the spleen is 3.2–4.2% per 100,000 population. Spleen cysts are rare (incidence 0.75 per 100,000). These are single or multiple, thin- and smooth-walled cavities filled with a transparent liquid. Distinguish between primary (or true) cysts, lined with epithelium, and secondary (or false), devoid of epithelial lining. Among the primary cysts, there are congenital cysts formed in the embryonic period due to the migration of peritoneal cells into the spleen tissue, dermoid and epidermoid cysts. A special group of primary cysts are parasitic cysts. Cystic tumors of the spleen include lymphangioma and lymphoma.The main difficulties in the diagnosis and differential diagnosis of cysts and cystic tumors of the spleen are associated with the rarity of this pathology and, as a consequence, a small number of works, including a significant number of the cases. However, in those works where a large number of the cases are described, most often this is one morphological form and an analysis of its various characteristics.Purpose. Based on the analysis of our own examination data of a significant number of patients with cysts and cystic tumors of the spleen, to assess the possibility of differential diagnosis of individual morphological forms according to ultrasound data.Materials and methods. 323 patients with cysts and cystic tumors of the spleen from 15 to 77 years old (men – 105 (32.5%); women – 218 (67.5%) were treated at A.V. Vishnevsky National Medical Research Center of Surgery for the period from 1980 to 2020. All patients underwent ultrasound during examination. Surgical treatment was carried out in various ways – (85.1%), when making a preoperative diagnosis of an uncomplicated spleen cyst of small size, dynamic observation was carried out (verification by puncture biopsy data).Results. Morphological verification of cysts and cystic tumors of the spleen was presented as follows (taking into account possible difficulties in identifying the epithelial lining): true cyst – 182 (56.4%); dermoid cyst – 3 (0.9%) (malignant – in 1 case); pseudocyst – 16 (5.0%); pancreatogenic – 34 (10.5%); echinococcus – 52 (16.1%); lymphangioma – 24 (7.4%); lymphoma – 10 (3.1%); ovarian cancer metastasis – 2 (0.6%). The article describes the ultrasound signs of the above forms of the lesions with an emphasis on the complexity of diagnosis.Conclusions. Primary and parasitic spleen cysts are well differentiated according to ultrasound; false cysts of the spleen, depending on the cause of their occurrence, can create difficulties in their identification and differentiation (they require careful dynamic control); cystic tumors of the spleen should be differentiated from malignant tumors and metastases of a cystic structure, as a result of which such vigilance should always be present when they are detected.

State-of-the-art MR Imaging of Fat-containing Focal Lesions of the Liver

2019 ◽  
Vol 15 (5) ◽  
pp. 435-442
Author(s):  
Joanna Podgorska ◽  
Agnieszka Anysz-Grodzicka ◽  
Andrzej Cieszanowski
Keyword(s):  
Differential Diagnosis ◽  
Imaging Techniques ◽  
Hepatobiliary Phase ◽  
Focal Lesions ◽  
Dysplastic Nodules ◽  
Nodular Hyperplasia ◽  
Specific Finding ◽  
Magnetic Resonance Imaging Mri ◽  
Adrenal Rest ◽  
Mri Characteristics

Background: Fat can be identified in numerous liver lesions, and usually is not a specific finding. Distinguishing between different kinds of fatty deposits is an important part of differential diagnosis. Magnetic Resonance Imaging (MRI) is superior to other imaging techniques because it allows distinguishing intracellular from macroscopic fat. Discussion: Intracellular lipid may be found in focal hepatic steatosis, hepatic adenoma, hepatocellular carcinoma and, less commonly, in focal nodular hyperplasia as well as regenerative and dysplastic nodules. Macroscopic fat is seen in angiomyolipoma, lipoma, metastases from fatcontaining neoplasms, primary or metastatic liposarcoma, hydatid cyst, pseudolipoma of the Glisson capsule, pericaval fat collection, lipopeliosis, hepatic teratoma, focal hepatic extramedullary haematopoiesis and adrenal rest tumour. Conclusion: Liver nodules should be characterised with regard to underlying liver condition, MRI characteristics and contrast enhancement pattern, including hepatobiliary phase. In many cases, identification of fatty content may help narrowing the differential diagnosis.

scholarly journals Performance of Ultrasound Techniques and the Potential of Artificial Intelligence in the Evaluation of Hepatocellular Carcinoma and Non-Alcoholic Fatty Liver Disease

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 790
Author(s):  
Monica Lupsor-Platon ◽  
Teodora Serban ◽  
Alexandra Iulia Silion ◽  
George Razvan Tirpe ◽  
Alexandru Tirpe ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Hepatocellular Carcinoma ◽  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Liver Lesion ◽  
Focal Liver Lesion ◽  
Ultrasound Contrast Agents ◽  
Alcoholic Fatty Liver ◽  
Alcoholic Fatty Liver Disease

Global statistics show an increasing percentage of patients that develop non-alcoholic fatty liver disease (NAFLD) and NAFLD-related hepatocellular carcinoma (HCC), even in the absence of cirrhosis. In the present review, we analyzed the diagnostic performance of ultrasonography (US) in the non-invasive evaluation of NAFLD and NAFLD-related HCC, as well as possibilities of optimizing US diagnosis with the help of artificial intelligence (AI) assistance. To date, US is the first-line examination recommended in the screening of patients with clinical suspicion of NAFLD, as it is readily available and leads to a better disease-specific surveillance. However, the conventional US presents limitations that significantly hamper its applicability in quantifying NAFLD and accurately characterizing a given focal liver lesion (FLL). Ultrasound contrast agents (UCAs) are an essential add-on to the conventional B-mode US and to the Doppler US that further empower this method, allowing the evaluation of the enhancement properties and the vascular architecture of FLLs, in comparison to the background parenchyma. The current paper also explores the new universe of AI and the various implications of deep learning algorithms in the evaluation of NAFLD and NAFLD-related HCC through US methods, concluding that it could potentially be a game changer for patient care.

scholarly journals Impact of inter-reader contouring variability on textural radiomics of colorectal liver metastases

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Francesco Rizzetto ◽  
Francesca Calderoni ◽  
Cristina De Mattia ◽  
Arianna Defeudis ◽  
Valentina Giannini ◽  
...  
Keyword(s):  
Liver Metastases ◽  
Hausdorff Distance ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Liver Lesion ◽  
Dice Coefficient ◽  
Rf Values ◽  
Enhanced Computed Tomography ◽  
Relative Change ◽  
The Impact

Abstract Background Radiomics is expected to improve the management of metastatic colorectal cancer (CRC). We aimed at evaluating the impact of liver lesion contouring as a source of variability on radiomic features (RFs). Methods After Ethics Committee approval, 70 liver metastases in 17 CRC patients were segmented on contrast-enhanced computed tomography scans by two residents and checked by experienced radiologists. RFs from grey level co-occurrence and run length matrices were extracted from three-dimensional (3D) regions of interest (ROIs) and the largest two-dimensional (2D) ROIs. Inter-reader variability was evaluated with Dice coefficient and Hausdorff distance, whilst its impact on RFs was assessed using mean relative change (MRC) and intraclass correlation coefficient (ICC). For the main lesion of each patient, one reader also segmented a circular ROI on the same image used for the 2D ROI. Results The best inter-reader contouring agreement was observed for 2D ROIs according to both Dice coefficient (median 0.85, interquartile range 0.78–0.89) and Hausdorff distance (0.21 mm, 0.14–0.31 mm). Comparing RF values, MRC ranged 0–752% for 2D and 0–1567% for 3D. For 24/32 RFs (75%), MRC was lower for 2D than for 3D. An ICC > 0.90 was observed for more RFs for 2D (53%) than for 3D (34%). Only 2/32 RFs (6%) showed a variability between 2D and circular ROIs higher than inter-reader variability. Conclusions A 2D contouring approach may help mitigate overall inter-reader variability, albeit stable RFs can be extracted from both 3D and 2D segmentations of CRC liver metastases.

scholarly journals Evaluation of Parotid Gland Function using Equivalent Cross-relaxation Rate Imaging Applied Magnetization Transfer Effect

2012 ◽  
Vol 53 (1) ◽  
pp. 138-144 ◽  
Author(s):  
Hidetoshi SHIMIZU ◽  
Shigeru MATSUSHIMA ◽  
Yasutomi KINOSADA ◽  
Hiroki MIYAMURA ◽  
Natsuo TOMITA ◽  
...  
Keyword(s):  
Parotid Gland ◽  
Relaxation Rate ◽  
Magnetization Transfer ◽  
Transfer Effect ◽  
Cross Relaxation ◽  
Gland Function

scholarly journals Fast Isotopic Exchange between Mitochondria and Cytosol in Brain Revealed by Relayed 13C Magnetization Transfer Spectroscopy

2009 ◽  
Vol 29 (4) ◽  
pp. 661-669 ◽  
Author(s):  
Jehoon Yang ◽  
Su Xu ◽  
Jun Shen
Keyword(s):  
Isotopic Exchange ◽  
Tricarboxylic Acid Cycle ◽  
Magnetization Transfer ◽  
Tricarboxylic Acid ◽  
Transfer Effect ◽  
Resonance Spectroscopy ◽  
Exchange Reactions ◽  
Acid Cycle ◽  
Longitudinal Relaxation

In vivo13C magnetic resonance spectroscopy has been applied to studying brain metabolic processes by measuring 13C label incorporation into cytosolic pools such as glutamate and aspartate. However, the rate of exchange between mitochondrial α-ketoglutarate/oxaloacetate and cytosolic glutamate/aspartate ( Vx) extracted from metabolic modeling has been controversial. Because brain fumarase is exclusively located in the mitochondria, and mitochondrial fumarate is connected to cytosolic aspartate through a chain of fast exchange reactions, it is possible to directly measure Vx from the four-carbon side of the tricarboxylic acid cycle by magnetization transfer. In isoflurane-anesthetized adult rat brain, a relayed 13C magnetization transfer effect on cytosolic aspartate C2 at 53.2ppm was detected after extensive signal averaging with fumarate C2 at 136.1ppm irradiated using selective radiofrequency pulses. Quantitative analysis using Bloch–McConnell equations and a four-site exchange model found that VxE13–19 µmol per g per min (≫ VTCA, the tricarboxylic acid cycle rate) when the longitudinal relaxation time of malate C2 was assumed to be within ±33% of that of aspartate C2. If VxE VTCA, the isotopic exchange between mitochondria and cytosol would be too slow on the time scale of 13C longitudinal relaxation to cause a detectable magnetization transfer effect.

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