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1.
Ultrasonography ; : 164-170, 2022.
Article in English | WPRIM | ID: wpr-919560

ABSTRACT

Purpose@#This study aimed to determine the diagnostic performance of the controlled attenuation parameter (CAP) measured using transient elastography (TE) for assessing macrovesicular steatosis (MaS) in potential living liver donors using same-day biopsy as a reference standard. @*Methods@#This retrospective study included 204 living liver donor candidates who underwent TE and liver biopsy on the same day between July 2013 and June 2014. The histologic degree of MaS was determined. The area under the receiver operating characteristic curve (AUROC) was used to evaluate the performance of CAP for diagnosing MaS of >10%, and the optimal cutoff value was identified using the maximal Youden index. @*Results@#Based on liver biopsy, 185 subjects had MaS of ≤10% and 19 had MaS of >10%. The CAP value was significantly correlated with the percentage of MaS on liver biopsy (r=0.635, P10% than in those with MaS of ≤10% (300 dB/m vs. 209 dB/m, P10% by CAP was 0.938 (95% confidence interval, 0.896 to 0.967), and a CAP of >259 dB/m yielded a sensitivity of 84.2% and a specificity of 92.4%. @*Conclusion@#The CAP measured using TE was significantly correlated with MaS and accurately detected substantial MaS in potential living liver donors. The CAP is a promising tool for the noninvasive diagnosis of MaS and may be used to screen unsuitable living liver donor candidates.

2.
Korean Journal of Radiology ; : 52-59, 2022.
Article in English | WPRIM | ID: wpr-918239

ABSTRACT

Objective@#To investigate whether the diagnostic performance of CT angiography (CTA) could be improved by modifying the conventional criterion (anastomosis site abnormality) to diagnose hepatic artery occlusion (HAO) after liver transplantation (LT) in suspected patients with Doppler ultrasound (US) abnormalities. @*Materials and Methods@#One hundred thirty-four adult LT recipients (88 males and 46 females; mean age, 52.7 years) with suspected HAO on Doppler US (40 HAO and 94 non-HAO according to the reference standards) were included. We evaluated 1) abnormalities in the HA anastomosis, categorized as a cutoff, ≥ 50% stenosis at the anastomotic site, or diffuse stenosis at both graft and recipient sides around the anastomosis, and 2) abnormalities in the distal run-off, including invisibility or irregular, faint, and discontinuous enhancement. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the conventional (considering anastomosis site abnormalities alone) and modified CTA criteria (abnormalities in both the anastomosis site and distal run-off) for the diagnosis of HAO were calculated and compared using the McNemar test. @*Results@#By using the conventional criterion to diagnose HAO, the sensitivity, specificity, PPV, NPV, and accuracy were 100% (40/40), 74.5% (70/94), 62.5% (40/64), 100% (70/70), and 82.1% (110/134), respectively. The modified criterion for diagnosing HAO showed significantly increased specificity (93.6%, 88/94) and accuracy (93.3%, 125/134) compared to that with the conventional criterion (p = 0.001 and 0.002, respectively), although the sensitivity (92.5%, 37/40) decreased slightly without statistical significance (p = 0.250). @*Conclusion@#The modified criterion considering abnormalities in both the anastomosis site and distal run-off improved the diagnostic performance of CTA for HAO in suspected patients with Doppler US abnormalities, particularly by increasing the specificity.

3.
Endocrinology and Metabolism ; : 672-677, 2021.
Article in English | WPRIM | ID: wpr-898223

ABSTRACT

Background@#Sarcopenia is defined as the loss of skeletal muscle mass and is associated with negative clinical outcomes. This study aimed to establish sex-specific cutoff values for the skeletal muscle area (SMA) and skeletal muscle index (SMI) at the third lumbar vertebral (L3) level using computed tomography (CT) imaging to identify sarcopenia in healthy Korean liver donors. @*Methods@#This retrospective study included 659 healthy liver donors (408 men and 251 women) aged 20 to 60 years who had undergone abdominal CT examinations between January 2017 and December 2018. Assessment of body composition was performed with an automated segmentation technique using a deep-learning system. Sex-specific SMA and SMI distributions were assessed, and cutoff values for determining sarcopenia were defined as values at either two standard deviations (SDs) below the mean reference value or below the fifth percentile. @*Results@#Using the SD definition, cutoff values for SMA and SMI were 117.04 cm2 and 39.33 cm2/m2, respectively, in men and 71.39 cm2 and 27.77 cm2/m2, respectively, in women. Using the fifth percentile definition, cutoff values for SMA and SMI were 126.88 cm2 and 40.96 cm2/m2, respectively, in men and 78.85 cm2 and 30.60 cm2/m2, respectively, in women. @*Conclusion@#Our data provide sex-specific cutoff values for the SMA and SMI at the L3 level measured by CT imaging in a healthy Korean population, which may be applicable for identifying sarcopenia in this population.

4.
Endocrinology and Metabolism ; : 672-677, 2021.
Article in English | WPRIM | ID: wpr-890519

ABSTRACT

Background@#Sarcopenia is defined as the loss of skeletal muscle mass and is associated with negative clinical outcomes. This study aimed to establish sex-specific cutoff values for the skeletal muscle area (SMA) and skeletal muscle index (SMI) at the third lumbar vertebral (L3) level using computed tomography (CT) imaging to identify sarcopenia in healthy Korean liver donors. @*Methods@#This retrospective study included 659 healthy liver donors (408 men and 251 women) aged 20 to 60 years who had undergone abdominal CT examinations between January 2017 and December 2018. Assessment of body composition was performed with an automated segmentation technique using a deep-learning system. Sex-specific SMA and SMI distributions were assessed, and cutoff values for determining sarcopenia were defined as values at either two standard deviations (SDs) below the mean reference value or below the fifth percentile. @*Results@#Using the SD definition, cutoff values for SMA and SMI were 117.04 cm2 and 39.33 cm2/m2, respectively, in men and 71.39 cm2 and 27.77 cm2/m2, respectively, in women. Using the fifth percentile definition, cutoff values for SMA and SMI were 126.88 cm2 and 40.96 cm2/m2, respectively, in men and 78.85 cm2 and 30.60 cm2/m2, respectively, in women. @*Conclusion@#Our data provide sex-specific cutoff values for the SMA and SMI at the L3 level measured by CT imaging in a healthy Korean population, which may be applicable for identifying sarcopenia in this population.

5.
Acta Pharmaceutica Sinica B ; (6): 2362-2373, 2020.
Article in English | WPRIM | ID: wpr-881117

ABSTRACT

The short release half-life of carbon monoxide (CO) is a major obstacle to the effective therapeutic use of carbon monoxide-releasing molecule-2 (CORM-2). The potential of CORM-2-entrapped ultradeformable liposomes (CORM-2-UDLs) to enhance the release half-life of CO and alleviate skin inflammation was investigated in the present study. CORM-2-UDLs were prepared by using soy phosphatidylcholine to form lipid bilayers and Tween 80 as an edge activator. The deformability of CORM-2-UDLs was measured and compared with that of conventional liposomes by passing formulations through a filter device at a constant pressure. The release profile of CO from CORM-2-UDLs was evaluated by myoglobin assay.

6.
Korean Journal of Radiology ; : 459-468, 2019.
Article in English | WPRIM | ID: wpr-741418

ABSTRACT

OBJECTIVE: To investigate whether diagnostic performance of contrast-enhanced ultrasound (CEUS) could be improved with modified criteria to diagnose significant hepatic artery occlusion (HAO) and to determine the role of CEUS in patients with a tardus-parvus hepatic artery (HA) pattern on Doppler US. MATERIALS AND METHODS: Among 2679 adult liver transplantations performed over 7 years, HAO was suspected in 288 recipients, based on Doppler ultrasound. Among them, 130 patients underwent CEUS. After excluding two technical failures, 128 CEUS images were retrospectively reviewed to search for abnormal findings, such as no HA enhancement, abnormal HA enhancement (delayed, faint, and discontinuous enhancement), and perfusion defect in the liver parenchyma. The performance CEUS abnormalities were assessed in the patients overall and in subgroups based on Doppler ultrasound abnormality (group A, no flow; group B, tardus-parvus pattern) and were compared based on the area under the receiver operating characteristic curve (AUC). RESULTS: HAO were diagnosed in 41 patients by surgery, angiography, or follow-up abnormality. By using the conventional criterion (no HA enhancement) to diagnose HAO in patients overall, the sensitivity, specificity, and AUC were 58.5%, 100%, and 0.793, respectively. Modified criteria for HAO (no HA enhancement, abnormal enhancement, or parenchymal perfusion defect) showed statistically significantly increased sensitivity (97.6%, 40/41) and AUC (0.959) (p < 0.001), although the specificity (95.4%, 83/87) was slightly decreased. The sensitivity and specificity of the modified criteria in Groups A and B were 97.1% (33/34) and 95.7% (22/23), and 100% (7/7) and 95.3% (61/64), respectively. CONCLUSION: Modified criteria could improve diagnostic performance of CEUS for HAO, particularly by increasing sensitivity. CEUS could be useful for diagnosing HAO even in patients with a tardus-parvus HA pattern on Doppler US, using modified criteria.


Subject(s)
Adult , Humans , Angiography , Area Under Curve , Contrast Media , Diagnosis , Follow-Up Studies , Hepatic Artery , Liver Transplantation , Liver , Perfusion , Retrospective Studies , ROC Curve , Sensitivity and Specificity , Ultrasonography
7.
The Korean Journal of Gastroenterology ; : 356-361, 2019.
Article in English | WPRIM | ID: wpr-787221

ABSTRACT

Biliary adenofibroma is a rare tumor with a bile duct origin characterized by a complex tubulocystic non-mucin secreting biliary epithelium with abundant fibrous stroma. The MRI features of biliary adenofibroma are not well established. The authors encountered two patients with biliary adenofibroma and reviewed the literature focusing on the MRI findings. A well-circumscribed multicystic tumor with septal enhancement and no intrahepatic bile duct communication may be the characteristic MRI findings of biliary adenofibroma.


Subject(s)
Humans , Adenofibroma , Bile Ducts , Bile Ducts, Intrahepatic , Epithelium , Magnetic Resonance Imaging
8.
Clinical and Molecular Hepatology ; : 54-60, 2018.
Article in English | WPRIM | ID: wpr-713311

ABSTRACT

BACKGROUND/AIMS: Computed tomography (CT) hepatic volumetry is currently accepted as the most reliable method for preoperative estimation of graft weight in living donor liver transplantation (LDLT). However, several factors can cause inaccuracies in CT volumetry compared to real graft weight. The purpose of this study was to determine the frequency and degree of resection plane-dependent error in CT volumetry of the right hepatic lobe in LDLT. METHODS: Forty-six living liver donors underwent CT before donor surgery and on postoperative day 7. Prospective CT volumetry (VP) was measured via the assumptive hepatectomy plane. Retrospective liver volume (VR) was measured using the actual plane by comparing preoperative and postoperative CT. Compared with intraoperatively measured weight (W), errors in percentage (%) VP and VR were evaluated. Plane-dependent error in VP was defined as the absolute difference between VP and VR. % plane-dependent error was defined as follows: |VP–VR|/W∙100. RESULTS: Mean VP, VR, and W were 761.9 mL, 755.0 mL, and 696.9 g. Mean and % errors in VP were 73.3 mL and 10.7%. Mean error and % error in VR were 64.4 mL and 9.3%. Mean plane-dependent error in VP was 32.4 mL. Mean % plane-dependent error was 4.7%. Plane-dependent error in VP exceeded 10% of W in approximately 10% of the subjects in our study. CONCLUSIONS: There was approximately 5% plane-dependent error in liver VP on CT volumetry. Plane-dependent error in VP exceeded 10% of W in approximately 10% of LDLT donors in our study. This error should be considered, especially when CT volumetry is performed by a less experienced operator who is not well acquainted with the donor hepatectomy plane.


Subject(s)
Humans , Cone-Beam Computed Tomography , Hepatectomy , Liver Transplantation , Liver , Living Donors , Methods , Organ Size , Prospective Studies , Retrospective Studies , Tissue Donors , Transplants
9.
Clinical and Molecular Hepatology ; : 224-229, 2017.
Article in English | WPRIM | ID: wpr-219272

ABSTRACT

BACKGROUND/AIMS: Clinical validation is required to determine whether Doppler measurements are comparable before and after administering ultrasound contrast agent (USCA). The purpose of this study is to explore whether the use of USCA affects spectral Doppler analysis in recipients of liver transplantation (LT). METHODS: For this study, 36 patients were examined using Doppler ultrasonography (US) along with a contrast-enhanced US for surveillance of vascular complications after LT. The following spectral Doppler US parameters were measured before and after administration of USCA: peak systolic velocity, end-diastolic velocity, resistive index, and systolic acceleration time of the graft hepatic artery; peak flow velocity of the graft portal vein; and peak flow velocity and venous pulsatility index of the graft hepatic vein. RESULTS: The mean peak systolic and end-diastolic velocities of the hepatic artery and the peak flow velocity of the portal and hepatic veins were increased after intravenously administration of the USCA, ranging from 10% to 13%. However, the changes were not statistically significant (P=0.097, 0.103, 0.128, and 0.190, respectively). There were no significant differences in other measured parameters, including the resistive index (P=0.205) and systolic acceleration time (P=0.489) of the hepatic artery and venous pulsatility index (P=0.494) of the hepatic vein. CONCLUSIONS: The measured velocities of graft hepatic vessels tended to increase after administration of USCA, but without statistical significance. The comparison of serial Doppler parameters with or without injection of USCA is valid during Doppler surveillance in recipients of LT.


Subject(s)
Humans , Acceleration , Contrast Media , Doppler Effect , Hepatic Artery , Hepatic Veins , Liver Transplantation , Liver , Microbubbles , Portal Vein , Transplants , Ultrasonography , Ultrasonography, Doppler
10.
Clinical and Molecular Hepatology ; : 406-414, 2016.
Article in English | WPRIM | ID: wpr-188157

ABSTRACT

According to the increasing need for accurate staging of hepatic fibrosis, the ultrasound (US) elastography techniques have evolved significantly over the past two decades. Currently, US elastography is increasingly used in clinical practice. Previously published studies have demonstrated the excellent diagnostic performance of US elastography for the detection and staging of liver fibrosis. Although US elastography may seem easy to perform and interpret, there are many technical and clinical factors which can affect the results of US elastography. Therefore, clinicians who are involved with US elastography should be aware of these factors. The purpose of this article is to present a brief overview of US techniques with the relevant technology, the clinical indications, diagnostic performance, and technical and biological factors which should be considered in order to avoid misinterpretation of US elastography results.


Subject(s)
Humans , Disease Progression , Elasticity Imaging Techniques/instrumentation , Fatty Liver/complications , Hypertension, Portal/complications , Liver/diagnostic imaging , Liver Cirrhosis/diagnostic imaging
11.
Clinical and Molecular Hepatology ; : 398-401, 2015.
Article in English | WPRIM | ID: wpr-91722
12.
Korean Journal of Radiology ; : 1207-1215, 2015.
Article in English | WPRIM | ID: wpr-102547

ABSTRACT

Gadoxetate disodium is a widely used magnetic resonance (MR) contrast agent for liver MR imaging, and it provides both dynamic and hepatobiliary phase images. However, acquiring optimal arterial phase images at liver MR using gadoxetate disodium is more challenging than using conventional extracellular MR contrast agent because of the small volume administered, the gadolinium content of the agent, and the common occurrence of transient severe motion. In this article, we identify the challenges in obtaining high-quality arterial-phase images of gadoxetate disodium-enhanced liver MR imaging and present strategies for optimizing arterial-phase imaging based on the thorough review of recent research in this field.


Subject(s)
Humans , Angiography , Arteries/anatomy & histology , Contrast Media/chemistry , Gadolinium DTPA/chemistry , Liver/diagnostic imaging , Magnetic Resonance Imaging
13.
Clinical and Molecular Hepatology ; : 95-103, 2015.
Article in English | WPRIM | ID: wpr-64637

ABSTRACT

The role of imaging is crucial for the surveillance, diagnosis, staging and treatment monitoring of hepatocellular carcinoma (HCC). Over the past few years, considerable technical advances were made in imaging of HCCs. New imaging technology, however, has introduced new challenges in our clinical practice. In this article, the current status of clinical imaging techniques for HCC is addressed. The diagnostic performance of imaging techniques in the context of recent clinical guidelines is also presented.


Subject(s)
Humans , Carcinoma, Hepatocellular/diagnosis , Contrast Media/chemistry , Ferric Compounds/chemistry , Iron/chemistry , Liver Neoplasms/diagnosis , Magnetic Resonance Imaging , Meglumine/analogs & derivatives , Organometallic Compounds/chemistry , Oxides/chemistry , Tomography, X-Ray Computed
14.
Clinical and Molecular Hepatology ; : 314-317, 2015.
Article in English | WPRIM | ID: wpr-157195

ABSTRACT

Portal flow steal occasionally persists even after the liver transplantation, which may reduce the portal flow and thus threaten the patients' outcome. Therefore, pre- and peri-operative detection of portal steal phenomenon requiring radiological or surgical interruption is essential for the liver transplantation candidates as well as for the recipients.


Subject(s)
Adult , Humans , Male , Hepatitis B, Chronic/complications , Liver Cirrhosis/etiology , Liver Transplantation , Mesenteric Veins/diagnostic imaging
15.
Maxillofacial Plastic and Reconstructive Surgery ; : 224-229, 2014.
Article in English | WPRIM | ID: wpr-112267

ABSTRACT

The maxillary posterior area is the most challenging site for the dental implant. Although the sinus graft is a predictable and successful technique for rehabilitation of atrophic and pneumatized posterior maxilla, when there is severe destruction of alveolar bone, a very long crown length remains challenging after successful dental implants installation with sinus graft. We performed vertical augmentation of the maxillary posterior alveolar ridge using the allogenic block bone graft with a simultaneous sinus graft using allogenic and heterogenic bone chips. After about six months, we installed the dental implant. After this procedure, we achieved a more favorable crown-implant fixture ratio and better results clinically and biomechanically. This is a preliminary report of vertical augmentation of maxillary posterior alveolar ridge using allogenic block bone graft and simultaneous maxillary sinus graft. Further research requires longer observation and more patients.


Subject(s)
Humans , Alveolar Process , Alveolar Ridge Augmentation , Crowns , Dental Implants , Maxilla , Maxillary Sinus , Rehabilitation , Sinus Floor Augmentation , Transplants
17.
Korean Journal of Pathology ; : 307-310, 2014.
Article in English | WPRIM | ID: wpr-70526

ABSTRACT

No abstract available.


Subject(s)
Adult , Humans , Mandible , Myofibroma
19.
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons ; : 520-524, 2011.
Article in Korean | WPRIM | ID: wpr-785109
20.
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons ; : 425-429, 2011.
Article in Korean | WPRIM | ID: wpr-785096
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