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1.
Korean Journal of Radiology ; : 1093-1101, 2023.
Article in English | WPRIM | ID: wpr-1002413

ABSTRACT

Objective@#Cine magnetic resonance imaging (MRI) has emerged as a noninvasive method to quantitatively assess bowel motility. However, its accuracy in measuring various degrees of small bowel motility has not been extensively evaluated. We aimed to draw a quantitative small bowel motility score from cine MRI and evaluate its performance in a population with varying degrees of small bowel motility. @*Materials and Methods@#A total of 174 participants (28.5 ± 7.6 years; 135 males) underwent a 22-second-long cine MRI sequence (2-dimensional balanced turbo-field echo; 0.5 seconds per image) approximately 5 minutes after being intravenously administered 10 mg of scopolamine-N-butyl bromide to deliberately create diverse degrees of small bowel motility. In a manually segmented area of the small bowel, motility was automatically quantified using a nonrigid registration and calculated as a quantitative motility score. The mean value (MV) of motility grades visually assessed by two radiologists was used as a reference standard. The quantitative motility score’s correlation (Spearman’s ρ) with the reference standard and performance (area under the receiver operating characteristics curve [AUROC], sensitivity, and specificity) for diagnosing adynamic small bowel (MV of 1) were evaluated. @*Results@#For the MV of the quantitative motility scores at grades 1, 1.5, 2, 2.5, and 3, the mean ± standard deviation values were 0.019 ± 0.003, 0.027 ± 0.010, 0.033 ± 0.008, 0.032 ± 0.009, and 0.043 ± 0.013, respectively. There was a significant positive correlation between the quantitative motility score and the MV (ρ = 0.531, P < 0.001). The AUROC value for diagnosing a MV of 1 (i.e., adynamic small bowel) was 0.953 (95% confidence interval, 0.923–0.984). Moreover, the optimal cutoff for the quantitative motility score was 0.024, with a sensitivity of 100% (15/15) and specificity of 89.9% (143/159). @*Conclusion@#The quantitative motility score calculated from a cine MRI enables diagnosis of an adynamic small bowel, and potentially discerns various degrees of bowel motility.

2.
Ultrasonography ; : 83-92, 2022.
Article in English | WPRIM | ID: wpr-919561

ABSTRACT

Purpose@#The accurate detection and quantification of hepatic steatosis using a noninvasive method are important for the management of nonalcoholic fatty liver disease. We performed a systematic review and meta-analysis of the accuracy of the ultrasound-measured attenuation coefficient (AC) in the evaluation of hepatic steatosis. @*Methods@#The PubMed, Embase, and Cochrane databases were searched for prospective studies reporting the diagnostic accuracy of AC for assessing hepatic steatosis. The meta-analytic pooled sensitivity and specificity of AC for any grade of steatosis (S≥1) and advanced steatosis (S≥2) were estimated using a bivariate random-effects model. Meta-regression analysis was conducted to investigate the causes of heterogeneity among studies. @*Results@#Thirteen studies including 1,509 patients were identified. The pooled sensitivity and specificity of AC for S≥1 were 76% (95% confidence interval [CI], 73% to 80%; I2=43%) and 84% (95% CI, 77% to 89%; I2=74%), respectively, while for S≥2 they were 87% (95% CI, 83% to 91%; I2=0%) and 79% (95% CI, 75% to 83%; I2=59%), respectively. Study heterogeneity was associated with body mass index (BMI) and the prevalence of steatosis or significant fibrosis. @*Conclusion@#AC can be clinically useful for assessing hepatic steatosis, with good overall diagnostic performance. The data reported in the published literature differed according to BMI and the prevalence of steatosis or significant fibrosis, and careful interpretation with consideration of these factors might be needed.

3.
Korean Journal of Radiology ; : 30-41, 2022.
Article in English | WPRIM | ID: wpr-918241

ABSTRACT

Objective@#Computed tomography enterography (CTE) and magnetic resonance enterography (MRE) are considered substitutes for each other for evaluating Crohn’s disease (CD). However, the adequacy of mixing them for routine periodic follow-up for CD has not been established. This study aimed to compare MRE alone with the mixed use of CTE and MRE for the periodic follow-up of small bowel inflammation in patients with CD. @*Materials and Methods@#We retrospectively compared two non-randomized groups, each comprising 96 patients with CD. One group underwent CTE and MRE (MRE followed by CTE or vice versa) for the follow-up of CD (interval, 13–27 months [median, 22 months]), and the other group underwent MRE alone (interval, 15–26 months [median, 21 months]). However, these two groups were similar in clinical characteristics. Three independent readers from three different institutions determined whether inflammation had decreased, remained unchanged, or increased within the entire small bowel and the terminal ileum based on sequential enterography of the patients after appropriate blinding. We compared the two groups for inter-reader agreement and accuracy (terminal ileum only) using endoscopy as the reference standard for enterographic interpretation. @*Results@#The inter-reader agreement was greater in the MRE alone group for the entire small bowel (intraclass correlation coefficient [ICC]: 0.683 vs. 0.473; p = 0.005) and the terminal ileum (ICC: 0.656 vs. 0.490; p = 0.030). The interpretation accuracy was higher in the MRE alone group without statistical significance (70.9%–74.5% vs. 57.9%–64.9% in individual readers; adjusted odds ratio = 3.21; p = 0.077). @*Conclusion@#The mixed use of CTE and MRE was inferior to MRE alone in terms of inter-reader reliability and could probably be less accurate than MRE alone for routine monitoring of small bowel inflammation in patients with CD. Therefore, the consistent use of MRE is favored for this purpose.

4.
Korean Journal of Radiology ; : 529-538, 2022.
Article in English | WPRIM | ID: wpr-926780

ABSTRACT

Objective@#Since its introduction in 2011, the CT/MRI diagnostic Liver Imaging Reporting and Data System (LI-RADS) has been updated in 2014, 2017, and 2018. We evaluated the impact of CT/MRI diagnostic LI-RADS on liver MRI research methodology for the diagnosis of hepatocellular carcinoma (HCC). @*Materials and Methods@#The MEDLINE, EMBASE, and Cochrane databases were searched for original articles reporting the diagnostic performance of liver MRI for HCC between 2011 and 2019. The MRI techniques, image analysis methods, and diagnostic criteria for HCC used in each study were investigated. The studies were classified into three groups according to the year of publication (2011–2013, 2014–2016, and 2017–2019). We compared the percentage of studies adopting MRI techniques recommended by LI-RADS, image analysis methods in accordance with the lexicon defined in LI-RADS, and diagnostic criteria endorsed by LI-RADS. We compared the pooled sensitivity and specificity between studies that used the LI-RADS and those that did not. @*Results@#This systematic review included 179 studies. The percentages of studies using imaging techniques recommended by LI-RADS were 77.8% for 2011–2013, 85.7% for 2014–2016, and 84.2% for 2017–2019, with no significant difference (p = 0.951). After the introduction of LI-RADS, the percentages of studies following the LI-RADS lexicon were 0.0%, 18.4%, and 56.6% in the respective periods (p < 0.001), while the percentages of studies using the LI-RADS diagnostic imaging criteria were 0.0%, 22.9%, and 60.7%, respectively (p < 0.001). Studies that did not use the LI-RADS and those that used the LIRADS version 2018 showed no significant difference in sensitivity and specificity (86.3% vs. 77.7%, p = 0.102 and 91.4% vs. 89.9%, p = 0.770, respectively), with some difference in heterogeneity (I2 = 94.3% vs. 86.7% in sensitivity and I2 = 86.6% vs. 53.2% in specificity). @*Conclusion@#LI-RADS imparted significant changes in the image analysis methods and diagnostic criteria used in liver MRI research for the diagnosis of HCC.

5.
Ultrasonography ; : 387-397, 2021.
Article in English | WPRIM | ID: wpr-919524

ABSTRACT

Purpose@#According to the American Association for the Study of Liver Diseases (AASLD) guidelines, biopsy is a diagnostic option for focal hepatic lesions depending on the Liver Imaging Reporting and Data System (LI-RADS) category. We evaluated the diagnostic performance of ultrasonography-guided core-needle biopsy (CNB) according to LI-RADS categories. @*Methods@#A total of 145 High-risk patients for hepatocellular carcinoma (HCC) who underwent magnetic resonance imaging (MRI) followed by CNB for a focal hepatic lesion preoperatively were retrospectively enrolled. Focal hepatic lesions on MRI were evaluated according to LI-RADS version 2018. Pathologic results were categorized into HCC, non-HCC malignancies, and benignity. The categorization was defined as correct when the CNB pathology and surgical pathology reports were identical. Nondiagnostic results were defined as inadequate CNB pathology findings for a specific diagnosis. The proportion of correct categorizations was calculated for each LI-RADS category, excluding nondiagnostic results. @*Results@#After excluding 16 nondiagnostic results, 131 lesions were analyzed (45 LR-5, 24 LR-4, 4 LR-3, and 58 LR-M). All LR-5 lesions were HCC, and CNB correctly categorized 97.8% (44/45) of LR-5 lesions. CNB correctly categorized all 24 LR-4 lesions, 16.7% (4/24) of which were non-HCC malignancies. All LR-M lesions were malignant, and 62.1% (36/58) were non-HCC malignancies. CNB correctly categorized 93.1% (54/58) of LR-M lesions, and 12.5% (3/24) of lesions with CNB results of HCC were confirmed as non-HCC malignancies. @*Conclusion@#In agreement with AASLD guidelines, CNB could be helpful for LR-4 lesions, but is unnecessary for LR-5 lesions. In LR-M lesions, CNB results of HCC did not exclude non-HCC malignancy.

6.
Ultrasonography ; : 167-175, 2021.
Article in English | WPRIM | ID: wpr-919506

ABSTRACT

Purpose@#This study investigated the diagnostic outcome of ultrasound (US)-guided focal hepatic lesion biopsy in patients at risk for hepatocellular carcinoma (HCC) and evaluated the US visualization score as a risk factor for non-diagnostic results. @*Methods@#We retrospectively evaluated 208 focal hepatic lesions in 208 patients who underwent US-guided biopsy in 2016. Using the US Liver Imaging Reporting and Data System version 2017, each exam was assigned a US visualization score (A, B, or C). Final diagnoses were made using pathology reports, and biopsy results were categorized as diagnostic or non-diagnostic. Univariable and multivariable analyses were performed to determine risk factors for non-diagnostic results, including US visualization score and other clinical covariates. @*Results@#Of the 208 lesions, 85.1% were diagnostic and 14.9% were non-diagnostic. The rates of non-diagnostic results were 8.9%, 25.5%, and 57.1% for scores of A, B, and C, respectively. In the univariable analysis, scores of B or C were associated with a significantly higher rate of nondiagnostic results than scores of A (58.1% vs. 24.9%, P<0.001). In the multivariable analysis, US visualization score of B or C (adjusted odds ratio [aOR], 2.7; P=0.027), high-risk needle pathway usage (aOR, 5.7; P=0.001), and lesion size ≤2.0 cm (aOR, 2.7; P=0.024) were independent risk factors for non-diagnostic results. @*Conclusion@#US-guided biopsy had a high diagnostic yield for focal hepatic lesions in patients at risk for HCC. US visualization score of B or C, lesion size ≤2.0 cm, and high-risk needle pathway usage were independent risk factors for non-diagnostic results.

7.
The Korean Journal of Physiology and Pharmacology ; : 355-363, 2021.
Article in English | WPRIM | ID: wpr-896240

ABSTRACT

Dynamic changes in adipose tissue blood flow (ATBF) with nutritional status play a role in the regulation of metabolic and endocrine functions. Activation of the sympathetic nervous system via β-adrenergic receptors (β-AR) contributes to the control of postprandial enhancement of ATBF. Herein, we sought to identify the role of each β-AR subtype in the regulation of ATBF in mice. We monitored the changes in visceral epididymal ATBF (VAT BF), induced by local infusion of dobutamine, salbutamol, and CL316,243 (a selective β1-, β2-, and β3-AR agonist, respectively) into VAT of lean CD-1 mice and global adipose triglyceride lipase (ATGL) knockout (KO) mice, using laser Doppler flowmetry. Administration of CL316,243, known to promote lipolysis in adipocytes, significantly increased VAT BF of CD-1 mice to a greater extent compared to that of the vehicle, whereas administration of dobutamine or salbutamol did not produce significant differences in VAT BF. The increase in VAT BF induced by β3-AR stimulation disappeared in ATGL KO mice as opposed to their wild-type (WT) littermates, implying a role of ATGL-mediated lipolysis in the regulation of VAT BF. Different vascular reactivities occurred despite no significant differences in vessel density and adiposity between the groups. Additionally, the expression levels of the angiogenesis-related genes were significantly higher in VAT of ATGL KO mice than in that of WT, implicating an association of ATBF responsiveness with angiogenic activity in VAT. Our findings suggest a potential role of β3-AR signaling in the regulation of VAT BF via ATGL-mediated lipolysis in mice.

8.
The Korean Journal of Physiology and Pharmacology ; : 355-363, 2021.
Article in English | WPRIM | ID: wpr-903944

ABSTRACT

Dynamic changes in adipose tissue blood flow (ATBF) with nutritional status play a role in the regulation of metabolic and endocrine functions. Activation of the sympathetic nervous system via β-adrenergic receptors (β-AR) contributes to the control of postprandial enhancement of ATBF. Herein, we sought to identify the role of each β-AR subtype in the regulation of ATBF in mice. We monitored the changes in visceral epididymal ATBF (VAT BF), induced by local infusion of dobutamine, salbutamol, and CL316,243 (a selective β1-, β2-, and β3-AR agonist, respectively) into VAT of lean CD-1 mice and global adipose triglyceride lipase (ATGL) knockout (KO) mice, using laser Doppler flowmetry. Administration of CL316,243, known to promote lipolysis in adipocytes, significantly increased VAT BF of CD-1 mice to a greater extent compared to that of the vehicle, whereas administration of dobutamine or salbutamol did not produce significant differences in VAT BF. The increase in VAT BF induced by β3-AR stimulation disappeared in ATGL KO mice as opposed to their wild-type (WT) littermates, implying a role of ATGL-mediated lipolysis in the regulation of VAT BF. Different vascular reactivities occurred despite no significant differences in vessel density and adiposity between the groups. Additionally, the expression levels of the angiogenesis-related genes were significantly higher in VAT of ATGL KO mice than in that of WT, implicating an association of ATBF responsiveness with angiogenic activity in VAT. Our findings suggest a potential role of β3-AR signaling in the regulation of VAT BF via ATGL-mediated lipolysis in mice.

9.
Korean Journal of Radiology ; : 41-62, 2021.
Article in English | WPRIM | ID: wpr-875271

ABSTRACT

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited.The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

10.
Korean Journal of Radiology ; : 812-828, 2020.
Article | WPRIM | ID: wpr-833546

ABSTRACT

Objective@#To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). @*Materials and Methods@#PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. @*Results@#Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43– 0.77; I2 = 80.60) and summary specificity of 0.89 (95% CI, 0.80–0.94; I2 = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm2) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. @*Conclusion@#This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

11.
Korean Journal of Radiology ; : 385-398, 2019.
Article in English | WPRIM | ID: wpr-741426

ABSTRACT

OBJECTIVE: To compare the safety and efficacy of radioembolization with that of sorafenib for the treatment of hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). MATERIALS AND METHODS: MEDLINE, EMBASE, and Cochrane databases were searched for studies reporting outcomes in patients with HCC and PVTT treated with radioembolization or sorafenib. Meta-analyses of cumulative overall survival (OS) and Kaplan-Meier survival rates according to the time to progression (TTP) and incidence of adverse events (AEs) were performed. Subgroup analyses were conducted on 1-year OS data. RESULTS: Seventeen studies were identified (four involving radioembolization, 10 involving sorafenib, and three comparing both). Pooled OS rates were higher in the radioembolization group, notably at 6 months {76% (95% confidence interval [CI], 64–85%) vs. 54% (95% CI, 45–62%)} and 1 year (47% [95% CI, 38–57%] vs. 24% [95% CI, 18–30%]); TTP was also longer with radioembolization. In patients undergoing radioembolization, the proportion of patients with Eastern Cooperative Oncology Group status 0 (p < 0.0001), Child-Pugh A (p < 0.0001), extrahepatic metastasis (p = 0.0012), and a history of cancer treatment (p = 0.0048) was identified as a significant source of heterogeneity for the 1-year OS. Radioembolization was associated with a lower incidence of grade 3/4 AEs than sorafenib (9% [95% CI, 3–27%] vs. 28% [95% CI, 17–43%]). CONCLUSION: Compared with sorafenib, radioembolization is a safer and more effective treatment for HCC with PVTT and is associated with prolonged survival, delayed tumor progression, and fewer grade 3/4 AEs.


Subject(s)
Humans , Carcinoma, Hepatocellular , Incidence , Neoplasm Metastasis , Population Characteristics , Portal Vein , Survival Rate , Thrombosis
12.
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
13.
Korean Journal of Radiology ; : 1616-1626, 2019.
Article in English | WPRIM | ID: wpr-786370

ABSTRACT

OBJECTIVE: To compare the diagnostic accuracy of dynamic computed tomography (CT) and gadoxetate-enhanced magnetic resonance imaging (MRI) for characterization of hepatic lesions by using the Liver Imaging Reporting and Data System (LI-RADS) in a multicenter, off-site evaluation.MATERIALS AND METHODS: In this retrospective multicenter study, we evaluated 231 hepatic lesions (114 hepatocellular carcinomas [HCCs], 58 non-HCC malignancies, and 59 benign lesions) confirmed histologically in 217 patients with chronic liver disease who underwent both gadoxetate-enhanced MRI and dynamic CT at one of five tertiary hospitals. Four radiologists at different institutes independently reviewed all MR images first and the CT images 4 weeks later. They evaluated the major and ancillary imaging features and categorized each hepatic lesion according to the LI-RADS v2014. Diagnostic performance was calculated and compared using generalized estimating equations.RESULTS: MRI showed higher sensitivity and accuracy than CT for diagnosing hepatic malignancies; the pooled sensitivities, specificities, and accuracies for categorizing LR-5/5V/M were 59.0% vs. 72.4% (CT vs. MRI; p < 0.001), 83.5% vs. 83.9% (p = 0.906), and 65.3% vs. 75.3% (p < 0.001), respectively. CT and MRI showed comparable capabilities for differentiating between HCC and other malignancies, with pooled accuracies of 79.9% and 82.4% for categorizing LR-M, respectively (p = 0.139).CONCLUSION: Gadoxetate-enhanced MRI showed superior accuracy for categorizing LR-5/5V/M in hepatic malignancies in comparison with dynamic CT. Both modalities had comparable accuracies for distinguishing other malignancies from HCC.


Subject(s)
Humans , Academies and Institutes , Carcinoma, Hepatocellular , Contrast Media , Information Systems , Liver , Liver Diseases , Magnetic Resonance Imaging , Retrospective Studies , Tertiary Care Centers
14.
Korean Journal of Radiology ; : 938-949, 2018.
Article in English | WPRIM | ID: wpr-717628

ABSTRACT

OBJECTIVE: To systematically determine the treatment outcomes of percutaneous microwave ablation (MWA) in patients with malignant renal tumor. MATERIALS AND METHODS: Original studies that reported the clinical outcomes of MWA in patients with malignant renal tumors were identified in MEDLINE and EMBASE from 2012 to June 30, 2017. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic summary estimates of various clinical outcomes, including technical outcomes (technical success rate [TSR] and technical efficacy rate [TER]), oncologic outcomes (local tumor recurrence rate [LRR], cancer-specific survival rate [CSSR], and overall survival rate [OSR]), and complications. RESULTS: Among the 145 articles screened, 13 articles including 567 patients carrying 616 malignant renal tumors were included in the meta-analysis. The meta-analytic pooled TSR and TER were 97.3% (95% confidence interval, 94.3–99.4%; I2 = 0.0%) and 97.6% (95.0–99.4%, I2 = 48.5%), respectively. The meta-analytic pooled LRR was 2.1% (0.3–4.7%, I2 = 54.1%). At 1-, 2-, 3-, and 5-year follow-up time points, the meta-analytic pooled CSSRs were 99.1% (97.2–100.0%; I2 = 0.0%), 98.4% (95.1–100.0%; I2 = 31.2%), 97.6% (93.4–99.9%; I2 = 52.3%), and 96.9% (93.3–99.2%; I2 = 0.0%) respectively, while the OSRs were 98.3% (96.1–99.8%; I2 = 0.0%), 94.9% (91.7–97.5%; I2 = 0.0%), 86.8% (81.9–91.1%; I2 = 22.1%), and 81.9% (75.4–87.6%; I2 = 0.0%). In terms of major complications, a 1.8% (0.6–3.3%; I2 = 0.0%) rate of meta-analytic pooled incidence was found. CONCLUSION: Microwave ablation showed favorable technical and oncologic outcomes with a low incidence of major complications. Hence, image-guided percutaneous MWA can be considered as a safe and effective treatment for malignant renal tumors.


Subject(s)
Humans , Carcinoma, Renal Cell , Follow-Up Studies , Incidence , Kidney , Microwaves , Recurrence , Survival Rate
15.
Korean Journal of Radiology ; : 489-497, 2018.
Article in English | WPRIM | ID: wpr-715442

ABSTRACT

OBJECTIVE: To prospectively investigate the feasibility of using 2 small intravenous catheters for high-rate computed tomography (CT) contrast injection in patients lacking superficial veins capable of accommodating ≤ 20-gauge catheters. MATERIALS AND METHODS: Sixty-eight consecutive eligible adults referred for dynamic liver CT were enrolled; 58 had previously undergone liver CT, including 8 that experienced extravasation. Two 22- or 24-gauge catheters were placed in all patients after 2–5 venipunctures, and 2 mL/kg of contrast agent (370 mg I/mL) was split-administered through both catheters to achieve total flow rate of 4 mL/s. Patients' experience and examination success rate, defined as uneventful scans completed at 4 mL/s or at < 4 mL/s achieving standard image quality in all phases, were analyzed. Quantitative hepatic signal-to-noise and hepatic vascular contrast-to-noise ratios (CNRs) were compared with 30 control examinations scanned at 4 mL/s using an 18-gauge catheter. RESULTS: One case each of extravasation and severe injection pain caused the examination to be aborted. Success rate was 88.2% (60/68; 54 patients scanned at 4 mL/s, 6 at 3.5–3.9 mL/s). Fifty-five of 58 patients (94.8%) that had past CT regarded the venipuncture as more tolerable than (n = 36) or similar to (n = 19) past experiences; 45 of 58 patients (77.6%) found contrast injection less painful than (n = 35) or similar to (n = 10) past experiences. When compared with control examinations, signal-to-noise ratio was similar in all phases (p ≥ 0.502), but the hepatic arterial CNR in arterial phase was slightly inferior (p ≤ 0.047). CONCLUSION: Using 2 small intravenous catheters can effectively achieve high-rate CT contrast injection in patients lacking adequate superficial veins.


Subject(s)
Adult , Humans , Catheters , Contrast Media , Liver , Multidetector Computed Tomography , Patient Satisfaction , Phlebotomy , Prospective Studies , Quality Assurance, Health Care , Signal-To-Noise Ratio , Veins
16.
Korean Journal of Radiology ; : 1175-1187, 2015.
Article in English | WPRIM | ID: wpr-102550

ABSTRACT

In the field of diagnostic test accuracy (DTA), the use of systematic review and meta-analyses is steadily increasing. By means of objective evaluation of all available primary studies, these two processes generate an evidence-based systematic summary regarding a specific research topic. The methodology for systematic review and meta-analysis in DTA studies differs from that in therapeutic/interventional studies, and its content is still evolving. Here we review the overall process from a practical standpoint, which may serve as a reference for those who implement these methods.


Subject(s)
Humans , Databases, Factual , Diagnostic Tests, Routine/standards , ROC Curve , Research
17.
Korean Journal of Radiology ; : 1188-1196, 2015.
Article in English | WPRIM | ID: wpr-102549

ABSTRACT

Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies.


Subject(s)
Humans , Area Under Curve , Databases, Factual , Diagnostic Tests, Routine/statistics & numerical data , ROC Curve , Research , Software
18.
Journal of Breast Cancer ; : 295-298, 2014.
Article in English | WPRIM | ID: wpr-225641

ABSTRACT

Since recurrent bilateral breast infection due to nontuberculous mycobacterium (NTM) is rare, its diagnosis is easily overlooked; in addition, complete recovery is often difficult to achieve. We report a case of recurrent bilateral infection in a 35-year-old woman who had completed treatment for NTM. Although various infectious diseases show similar clinical conditions and imaging findings, recurrences should raise suspicion of NTM infection, and this possibility should be considered in differential diagnoses.


Subject(s)
Adult , Female , Humans , Abscess , Breast , Communicable Diseases , Diagnosis , Diagnosis, Differential , Nontuberculous Mycobacteria , Recurrence
20.
The Korean Journal of Physiology and Pharmacology ; : 405-409, 2013.
Article in English | WPRIM | ID: wpr-727504

ABSTRACT

We studied the sex different nicotine effect on evoked population spike amplitudes (ePSA) and connexin (Cx) expression in the hippocampus CA1 area of gerbils. Acute doses of nicotine bitartrate (0.5 mg/kg: NT-0.5) slightly reduced ePSA in males but markedly augmented that in females. Acute NT (5.0 mg/kg) markedly increased the ePSA in all gerbils. Unlike acute NT-0.5, repeated NT-0.5 injection (twice a day for 7 days) significantly increased the ePSA in males and slightly affected the NT-0.5 effect in females. The Cx36 and Cx43 expression levels as well as Cx expressing neuronal populations were significantly increased by repeated NT-0.5 in in both male and female gerbils, and particularly, Cx43 expression was somewhat prominent in females. These results demonstrated a sex difference with respect to the nicotine effect on hippocampal bisynaptic excitability, irrelevant to connexin expression.


Subject(s)
Animals , Female , Male , Connexins , Connexin 43 , Gerbillinae , Hippocampus , Neurons , Nicotine , Sex Characteristics
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