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1.
Journal of Chinese Physician ; (12): 1006-1009, 2018.
Article in Chinese | WPRIM | ID: wpr-705940

ABSTRACT

Objective To compare the diagnostic performances of real time of shear wave elastography (SWE) and strain ratio (SR) in differentiating benign and malignant liver tumors.Methods From March 2017 to August 2017,68 patients with 70 lesions were examined with SR and SWE respectively,the parameters of SWE were maximum real-time shear wave velocity (Vmax),average real-time shear wave velocity (Vmean) and real-time shear wave velocity elasticity ratio of lesion/peripheral liver tissue (Vratio).The receiver operating characteristic (ROC) curve of SWE and SR parameters were plotted to assess the value in distinguishing benign and malignant liver tumors.The results were compared using the area under the ROC curve (AUC).The sensitivity,specificity,accuracy of SWE and SR were calculated,The accuracy of the parameters with the largest AUC were compared between SWE and SR by McNemar test in differentiating focal liver lesions.Results The AUC of SR,Vmax,Vmean and Vratio were 0.948,0.868,0.918 and 0.956 respectively.The comparison of AUC reveals no significant difference between them.The sensitivity,specificity,accuracy of SR in differentiating benign and malignant liver tumors were 92.73%,93.33%,92.86% respectively (P >0.05).The SWE parameter with the largest AUC was Vratio.The sensitivity,specificity,accuracy of Vratio was 94.56%,100.00%,95.71%,respectively.The accuracy of Vratio and SR in differentiating benign and malignant liver tumors showed no significant difference (P >0.05).Conclusions The application of SWE and SR in the differential diagnosis of benign and malignant liver tumors is of high diagnostic value.They provide a new method for the differential diagnosis of liver tumor lesions,and the diagnostic value of both of them is equivalent.

2.
Journal of Chinese Physician ; (12): 816-819, 2018.
Article in Chinese | WPRIM | ID: wpr-705904

ABSTRACT

Objective The purpose of our study is to investigate the clinical value of virtual touch tissue quantification (VTQ)in the differential diagnosis of the benign and malignant liver tumor.Methods VTQ was used to inspect 53 patients with liver space-occupying lesions.Results After choosing the little lesions (the largest diameter less than 35 mm) from all the case groups,the VTQ value of the malignant group was higher than the hepatic hemangioma group (with significant differences among the different groups,P >0.05).Through the analysis of receiver operating characteristic curve (ROC),the optimal cutoff point as diagnosis reference value for differential diagnosis between malignant and benign groups was available.When the Area under the curve was 0.778,and with the VTQ value of 1.91 m/s,the sensitivity,specificity and Youden index was 78.6%,90.0%,0.686 respectively.The correlation analysis showed that the VTQ values of the lesion was positively correlated with the largest diameter of the lesion in the liver hemangioma group,with significant statistically differences (P < 0.05).The correlation index was 0.812.Conclusions VTQ could provide a new effective way to benign and malignant liver lesions in differential diagnosis.

3.
Journal of the Korean Radiological Society ; : 267-269, 2006.
Article in Korean | WPRIM | ID: wpr-142836

ABSTRACT

Nodular hepatic involvement of multiple myeloma is very rare. We report here on a case of nodular hepatic involvement of multiple myeloma that mimicked intrahepatic cholangiocarcinoma. In patients with multiple myeloma, hepatic involvement of the multiple myeloma might be included in the differential diagnosis of hepatic mass.


Subject(s)
Humans , Cholangiocarcinoma , Diagnosis, Differential , Liver , Multiple Myeloma
4.
Journal of the Korean Radiological Society ; : 267-269, 2006.
Article in Korean | WPRIM | ID: wpr-142833

ABSTRACT

Nodular hepatic involvement of multiple myeloma is very rare. We report here on a case of nodular hepatic involvement of multiple myeloma that mimicked intrahepatic cholangiocarcinoma. In patients with multiple myeloma, hepatic involvement of the multiple myeloma might be included in the differential diagnosis of hepatic mass.


Subject(s)
Humans , Cholangiocarcinoma , Diagnosis, Differential , Liver , Multiple Myeloma
5.
Journal of the Korean Radiological Society ; : 23-26, 2006.
Article in Korean | WPRIM | ID: wpr-92688

ABSTRACT

Fibrolamellar hepatocelluar carcinoma is a distinct clinicopathologic variant of hepatocellular carcinoma. We describe here the sonographic and CT findings of fibrolamellar hepatocellular carcinoma in a 17-year-old patient that mimicked hepatic malignant lymphoma due to the multiple small hypoattenuating nodules and extensive lymphadenopathy that we observed. We also include a review of the relevant literatures.


Subject(s)
Adolescent , Humans , Carcinoma, Hepatocellular , Liver Neoplasms , Lymphatic Diseases , Lymphoma , Ultrasonography
6.
Journal of the Korean Society of Medical Ultrasound ; : 19-22, 2005.
Article in Korean | WPRIM | ID: wpr-725470

ABSTRACT

Thymoma is the most common neoplasm in the anterior mediastinum, and extrathoracic involvement is rare. Moreover, cystic liver metastasis is extremely rare; few cases have been reported in the literature to date. We report here on a case of cystic liver metastasis of thymoma treated with surgical resection, describing the ultrasonography, CT and MRI findings.


Subject(s)
Liver , Magnetic Resonance Imaging , Mediastinum , Neoplasm Metastasis , Thymoma , Ultrasonography
7.
Korean Journal of Radiology ; : 185-198, 2004.
Article in English | WPRIM | ID: wpr-68893

ABSTRACT

The early assessment of the therapeutic response after percutaneous radiofrequency (RF) ablation is important, in order to correctly decide whether further treatment is necessary. The residual unablated tumor is usually depicted on contrast-enhanced multiphase helical computed tomography (CT) as a focal enhancing structure during the arterial and portal venous phases. Contrast-enhanced color Doppler and power Doppler ultrasonography (US) have also been used to detect residual tumors. Contrast-enhanced gray-scale US, using a harmonic technology which has recently been introduced, allows for the detection of residual tumors after ablation, without any of the blooming or motion artifacts usually seen on contrast-enhanced color or power Doppler US. Based on our experience and reports in the literature, we consider that contrast-enhanced gray-scale harmonic US constitutes a reliable alternative to contrast-enhanced multiphase CT for the early evaluation of the therapeutic response to RF ablation for liver cancer. This technique was also useful in targeting any residual unablated tumors encountered during additional ablation.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular/diagnostic imaging , Catheter Ablation , Contrast Media , Liver Neoplasms/diagnostic imaging , Polysaccharides , Suspensions , Tomography, Spiral Computed , Ultrasonography, Doppler/methods
8.
Journal of the Korean Radiological Society ; : 317-320, 2004.
Article in Korean | WPRIM | ID: wpr-49107

ABSTRACT

Pigmented liver cell adenoma is very rare benign hepatic tumor and only four cases have been reported in the literature until now. We experienced one case of pigmented liver cell adenoma with nodule-in-nodule appearance, and we report on the ultrasonographic, CT and pathologic findings.


Subject(s)
Adenoma, Liver Cell , Liver
9.
Journal of the Korean Radiological Society ; : 119-122, 2004.
Article in Korean | WPRIM | ID: wpr-118549

ABSTRACT

Familial adenomatous polyposis and hepatoblastoma are rare conditions; the latter is closely related to the FAP gene. We describe the imaging findings of hepatoblastoma in a patient with polyposis coli.


Subject(s)
Humans , Adenomatous Polyposis Coli , Colonic Neoplasms , Hepatoblastoma
10.
Korean Journal of Radiology ; : 91-100, 2003.
Article in English | WPRIM | ID: wpr-229497

ABSTRACT

OBJECTIVE: To determine the findings of various focal hepatic lesions at contrast-enhanced gray-scale ultrasound (US) using a coded harmonic angio (CHA) technique and emphasizing lesion characterization. MATERIALS AND METHODS: The study involved 95 patients with 105 focal hepatic lesions, namely 51 hepatocellular carcinomas (HCCs), 22 metastases, 22 hemangiomas, four cases of focal nodular hyperplasia (FNH), and six nontumorous nodules. After the injection of a microbubble contrast agent (SH U 508A), gray-scale harmonic US studies using a CHA technique were performed with a combination of continuous scanning to assess the intratumoral vasculature (vascular imaging) and interval-delay scanning to determine the sequential enhancement pattern (acoustic emission imaging). Each imaging pattern was categorized and analyzed. RESULTS: At vascular imaging, 69% of HCCs (35/51) showed irregular branching vessels, while in 91% of metastases (20/22) a peripherally stippled pattern was observed. Intratumoral vessels were absent in 95% of hemangiomas (21/22) and all nontumorous lesions (6/6), while in 75% of FNHs (3/4) a spoke-wheel pattern was evident. At acoustic emission imaging, 71% of HCCs (36/51) showed heterogeneous enhancement and 86% (19/22) of metastases showed rim- or flame-like peripheral enhancement during the early phase, with washout occurring in all HCCs and metastases (100%, 73/73) during the late phase. In hemangiomas, enhancement was either peripheral and nodular (19/22, 86%) or persistent and homogeneous (3/22, 14%), and 75% of FNHs (3/4) became isoechoic during the late phase. CONCLUSION: At contrast-enhanced gray-scale US using a CHA technique, a period of continuous scanning depicted the intratumoral vasculature, and interval-delay scanning demonstrated the sequential enhancement pattern. The characteristic findings of various focal hepatic lesions were thus determined.

11.
Korean Journal of Radiology ; : 124-129, 2003.
Article in English | WPRIM | ID: wpr-229493

ABSTRACT

OBJECTIVE: To compare phase-inversion sonography during the liver-specific phase of contrast enhancement using a microbubble contrast agent with conventional B-mode sonography for the detection of VX2 liver tumors. MATERIALS AND METHODS: Twenty-three rabbits, 18 of which had VX2 liver tumor implants, received a bolus injection of 0.6 g of Levovist (200 mg/ml). During the liver-specific phase of this agent, they were evaluated using both conventional sonography and contrast-enhanced phase-inversion harmonic imaging (CE-PIHI). Following sacrifice of the animals, pathologic analysis was performed and the reference standard thus obtained. The conspicuity, size and number of the tumors before and after contrast administration, as determined by a sonographer, were compared between the two modes and with the pathologic findings. RESULTS: CE-PIHI demonstrated marked hepatic parenchymal enhancement in all rabbits. For VX2 tumors detected at both conventional US and CE- PIHI, conspicuity was improved by contrast-enhanced PIHI. On examination of gross specimens, 52 VX2 tumors were identified. Conventional US correctly detected 18 of the 52 (34.6%), while PIHI detected 35 (67.3%) (p < 0.05). In particular, conventional US detected only three (8.3%) of the 36 tumors less than 10 mm in diameter, but CE-PIHI detected 19 such tumors (52.8%) (p < 0.05). CONCLUSION: Compared to conventional sonography, PIHI performed during the liver-specific phase after intravenous injection of Levovist is markedly better at detecting VX2 liver tumors.

12.
Korean Journal of Radiology ; : 224-233, 2003.
Article in English | WPRIM | ID: wpr-214907

ABSTRACT

OBJECTIVE: To analyze the contrast-enhancement patterns obtained at pulseinversion harmonic imaging (PIHI) of focal hepatic lesions, and to thus determine tumor vascularity and the acoustic emission effect. MATERIALS AND METHODS: We reviewed pulse-inversion images in 90 consecutive patients with focal hepatic lesions, namely hepatocellular carcinoma (HCC) (n=43), metastases (n=30), and hemangioma (n=17). Vascular and delayed phase images were obtained immediately and five minutes following the injection of a microbubble contrast agent. Tumoral vascularity at vascular phase imaging and the acoustic emission effect at delayed phase imaging were each classified as one of four patterns. RESULTS: Vascular phase images depicted internal vessels in 93% of HCCs, marginal vessels in 83% of metastases, and peripheral nodular enhancement in 71% of hemangiomas. Delayed phase images showed inhomogeneous enhancement in 86% of HCCs; hypoechoic, decreased enhancement in 93% of metastases; and hypoechoic and reversed echogenicity in 65% of hemangiomas. Vascular and delayed phase enhancement patterns were associated with a specificity of 91% or greater, and 92% or greater, respectively, and with positive predictive values of 71% or greater, and 85% or greater, respectively. CONCLUSION: Contrast-enhancement patterns depicting tumoral vascularity and the acoustic emission effect at PIHI can help differentiate focal hepatic lesions.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular/blood supply , Colon/pathology , Contrast Media/administration & dosage , Diagnosis, Differential , Hemangioma/blood supply , Image Enhancement/methods , Liver/pathology , Liver Neoplasms/blood supply , Lung/pathology , Microbubbles , Pancreas/pathology , Polysaccharides/administration & dosage , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Stomach/pathology
13.
Journal of the Korean Radiological Society ; : 359-366, 2001.
Article in Korean | WPRIM | ID: wpr-16780

ABSTRACT

PURPOSE: To assess the value of contrast-enhanced color Doppler ultrasonography(US) in the detection of ves-sels related to hepatocellular carcinoma(HCC). MATERIALS AND METHODS: Between July 1997 and April 2000, 76 HCCs in 70 patients (50 men and 20 women; mean age, 57.8 years) were confirmed histologically or clinically. Tumor site and size at gray scale US, and afferent, intratumoral and efferent color signals at precontrast and postcontrast color Doppler US were deter-mined. Afferent signals were classified as basket or penetrating type, and intratumoral signals as spotty, linear or mixed. Efferent signals were categorized as signal to portal vein or signal to hepatic vein, and postcontrast color signal changes as focal, general or marginal spotty type. We also measured the color percentage of intra-tumoral signals as seen during precontrast and postcontrast study. RESULTS: The detection rate changed from 41(53.9%) to 60(78.9%) in cases with afferent signals, from 50(65.8%) to 64(84.2%) in those with intratumoral signals, and from 6(7.9%) to 9(11.8%) in those with efferent signals. Overall, 74(97.4%) cases showed positive findings at postcontrast color Doppler US. The most common enhancing pattern was general, occurring in 33(43.4%) cases. The color percentage of intratumoral signals increased from an average of 8.2% to 34.9%. The detection rate of intratumoral signals from tumors less than 3 cm in diameter increased from 56.8% to 100%, and that of deeply-located tumor-related signals (17 cas-es) increased from 47.1% to 94.1%. CONCLUSION: The use of contrast enhanced color Doppler US increased the detection rate of afferent, intratumoral, and efferent signals, especially that of intratumoral signals from tumors less than 3 cm in diameter and signals from deeply located tumors. In addition, the modality can aid the diagnosis of HCC by evaluating tumor dynamics.


Subject(s)
Female , Humans , Male , Diagnosis , Hepatic Veins , Liver Neoplasms , Portal Vein , Ultrasonography, Doppler, Color
14.
Korean Journal of Radiology ; : 175-184, 2000.
Article in English | WPRIM | ID: wpr-74879

ABSTRACT

Although surgical resection remains the best option as potentially curative therapy for hepatocellular carcinoma, radiofrequency thermal ablation has begun to receive much attention as an effective minimally invasive technique for the local control of unresectable malignant hepatic tumors. Most recent radiofrequency devices equipped with a powerful generator and larger needle electrode permit larger thermal lesions, up to 5 cm in diameter, with a single ablation. In this article, the author reviews the technical developments and early clinical results obtained with radiofrequency ablation techniques.


Subject(s)
Aged , Female , Humans , Male , Carcinoma, Hepatocellular/surgery , Catheter Ablation/instrumentation , Liver Neoplasms/surgery , Middle Aged
15.
Korean Journal of Radiology ; : 185-190, 2000.
Article in English | WPRIM | ID: wpr-74878

ABSTRACT

OBJECTIVE: To document the imaging findings of hepatic cavernous heman-gioma detected in cirrhotic liver. MATERIALS AND METHODS: The imaging findings of 14 hepatic cavernous hemangiomas in ten patients with liver cirrhosis were retrospectively analyzed. A diagnosis of hepatic cavernous hemangioma was based on the findings of two or more of the following imaging studies: MR, including contrast-enhanced dynamic imaging (n = 10), dynamic CT (n = 4), hepatic arteriography (n = 9), and US (n =10). RESULTS: The mean size of the 14 hepatic hemangiomas was 0.9 (range, 0.5 -1.5) cm in the longest dimension. In 11 of these (79%), contrast-enhanced dynamic CT and MR imaging showed rapid contrast enhancement of the entire lesion during the early phase, and hepatic arteriography revealed globular enhancement and rapid filling-in. On contrast-enhanced MR images, three lesions (21%) showed partial enhancement until the 5-min delayed phases. US indicated that while three slowly enhancing lesions were homogeneously hypere-choic, 9 (82%) of 11 showing rapid enhancement were not delineated. CONCLUSION: The majority of hepatic cavernous hemangiomas detected in cirrhotic liver are small in size, and in many, hepatic arteriography and/or contrast-enhanced dynamic CT and MR imaging demonstrates rapid enhancement. US, however, fails to distinguish a lesion of this kind from its cirrhotic background.


Subject(s)
Female , Humans , Male , Diagnostic Imaging , Hemangioma, Cavernous/complications , Liver Cirrhosis/complications , Liver Neoplasms/complications , Magnetic Resonance Imaging , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed
16.
Journal of the Korean Radiological Society ; : 1167-1172, 1999.
Article in Korean | WPRIM | ID: wpr-46713

ABSTRACT

PURPOSE: To evaluate the efficacy of color and pulsed Doppler ultrasound (US) for the detection of arterial revascularization of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). MATERIALS AND METHODS: One hundred and four histologically proven HCCs (0.7-12.5 cm, mean 4.14 cm) of 87 consecutive patients who had undergone TACE using a Lipiodol-chemoagent suspension were examined using color Doppler equipment. The criteria for diagnosing arterial revascularization of HCC were detection of inward blood vessels within HCC and demonstration by spectral Doppler US of pulsatile arterial flow within the vessel. Color Doppler US was prospectively performed using a multi-Hertz probe (2.5-5 Hz), and was followed by digital subtraction angiography (DSA). RESULTS: In 37 of 104 HCCs in 87 patients treated with TACE, color and spectral Doppler US demonstrated intratumoral arterial flows, with peak systolic velocity of 4.2-220 (mean, 59) cm/sec. DSA revealed neovascularity or tumor stains in 38 HCCs (3.4-12.5 cm, mean 5.9 cm in size) including 37 which on Doppler US showed arterial flow. The remaining 66 of 104 HCCs (0.7-6.3 cm, mean 3.2 cm) did not stain during DSA. Doppler US showed a false negative result in only one HCC (4.6 cm, located at segment VII of the Couinaud classification), which stained faintly during DSA. The sensitivity, specificity, and accuracy of color and spectral Doppler US used for the detection of recurrent HCC were 97.4%, 100%, and 99%, respectively. CONCLUSIONS: Color and spectral Doppler US is an effective method for the evaluation of arterial revascularization of HCC after TACE.


Subject(s)
Humans , Angiography, Digital Subtraction , Blood Vessels , Carcinoma, Hepatocellular , Coloring Agents , Prospective Studies , Recurrence , Sensitivity and Specificity , Ultrasonography
17.
Journal of the Korean Radiological Society ; : 1051-1057, 1998.
Article in Korean | WPRIM | ID: wpr-229465

ABSTRACT

PURPOSE: To analyze the effect of various parameters used in PEIT on the short-term results of this procedurefor the treatment of small HCC. MATERIALS AND METHODS: Among 76 lesions in 63 patients with HCCs, 66 werediagnosed by tissue biopsy (n=30) or according to clinical features, tumor marker, and the results of angiographyand other diagnostic imagings (n=36). These patients underwent PEIT between November 1993 and October 1996 ; theindications for PEIT were nodular lesions less than 3cm in size, less than three in number, and unsuitable forsurgical resection or transcatheter arterial chemoembolization therapy. The effect of PEIT was evaluated by twophase spiral CT one month later (64 lesions) or by serial ultrasound for 6 months. We analyzed and graded theshort-term effect of PEIT on HCCs as complete remission (CR), partial remission (PR) or no change/aggravation(NC/AG). We also evaluated the correlation between the short-term results of PEIT and variable parameters such assize of the lesion, frequency of PEI per session, Child classification of the patient, the ratio of amount ofinjected ethanol per volume of the lesion, and (alpha-fetoprotein level before the procedure. RESULTS: Thetherapeutic effect of PEIT was CR in 45 lesions (59.2%), PR in 18(23.7%) and NC/AG in 13(17.1%). The size of thetumor, Child-Pugh class, number of injections per session and ratio of injected volume of ethanol to tumor volumewere factors affecting the therapeutic result (p <0.05). CONCLUSION: Sufficient knowledge of prognostic factorsaffecting the short-term results of PEIT might help improve the effects of therapy in patients ith small HCCs.


Subject(s)
Child , Humans , Biopsy , Carcinoma, Hepatocellular , Classification , Ethanol , Follow-Up Studies , Tomography, Spiral Computed , Ultrasonography
18.
Journal of the Korean Radiological Society ; : 1135-1142, 1998.
Article in Korean | WPRIM | ID: wpr-18508

ABSTRACT

PURPOSE: To determine the usefulness of microbubble contrast enhanced power Doppler ultrasonography (PDUS)for the detection of residual tumor in hepatocellular carcinomas (HCCs) treated by transcatheter arterialchemoembolization (TACE). MATERIALS AND METHODS: Fourteen nodular HCCs (size range: 1 - 7.3 cm, mean: 3.5) intwelve patients treated by TACE, and on the basis of follow-up liver CT, thought to have a residual tumor, wereincluded in this study. Between July 1997 and April 1998, PDUS examinations were performed with a 2-4 MHz convextransducer before and after intravenous injection of a microbubble contrast agent (Levovist(, Schering AG, Berlin,Germany). Real-time power Doppler ultrasonographic images were recorded on videotape and representative imageswere color-printed. Tumor vascularity was analyzed on real-time images with regard to its presence or absence, andchanges, and two observers reached a consensus. The results were compared with those of other diagnostic tests(three-phase helical CT, conventional angiography, percutaneous biopsy, and/or surgical pathology). RESULTS: Contrast-enhanced PDUS revealed intratumoral vascularity in ten of 14 tumors, none of which showed vascularity onunenhanced PDUS. In the remaining four tumors, both unenhanced and enhanced PDUS showed intratumoral tumorvascularity, which in all cases was more pronounced on enhanced than on unenhanced PDUS. Other diagnostic testsrevealed residual tumors in eleven lesions. CONCLUSION: Microbubble contrast-enhanced PDUS was more sensitivethan non-enhanced PDUS in depicting vascularity within a residual tumor and could be a useful method for thedetection of residual tumor in HCCs treated by TACE.


Subject(s)
Humans , Angiography , Biopsy , Carcinoma, Hepatocellular , Consensus , Follow-Up Studies , Injections, Intravenous , Liver , Microbubbles , Neoplasm, Residual , Tomography, Spiral Computed , Ultrasonography, Doppler , Videotape Recording
19.
Journal of the Korean Radiological Society ; : 125-127, 1997.
Article in Korean | WPRIM | ID: wpr-17843

ABSTRACT

Extrathoracic metastasis of a thymoma is rare ; we report a case of metastasis to the liver of a large solitary thymoma. Biopsy of the mass showed it to be predominantly lymphocytic and histologically the same as a primary thymoma operated on four years previously. On ultrasound and CT scan, the majority of the metastatic tumor was hemorrhagic, necrotic and/or cystic, with a peripheral, irregularly thick solid component and rather thin, smooth encapsulation.


Subject(s)
Biopsy , Liver , Neoplasm Metastasis , Thymoma , Tomography, X-Ray Computed , Ultrasonography
20.
Journal of the Korean Radiological Society ; : 129-131, 1997.
Article in English | WPRIM | ID: wpr-17842

ABSTRACT

A case of primary adenosquamous carcinoma of the liver is reported. A large cystic mass with irregular enhancing wall was seen in the left lobe of the liver; multiple hepatic cysts and metastatic nodules were scattered in both lobes. Sonoguided needle biopsy was performed and on histopathology, adenosquamous carcinoma was diagnosed. The radiologic and pathologic relationships of this unusual neoplasm are discussed.


Subject(s)
Biopsy, Needle , Carcinoma, Adenosquamous , Liver
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