Radiofrequency Ablation of Papillary Thyroid Microcarcinoma: A 10-Year Follow-Up Study

Purpose@#To investigate the efficacy and safety of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) after > 10 years of follow-up. @*Materials and Methods@#This study included five patients who underwent RFA to treat PTMCs (five lesions, mean diameter 0.5 cm, range 0.4–0.7 cm) between November 2006 and December 2009. The inclusion criteria were histopathologically confirmed PTMCs, a single PTMC lesion without extrathyroidal extension, no metastasis, and ineligibility or refusal to undergo surgery. RFA was performed by a single radiologist using a radiofrequency generator and an internally cooled electrode. We retrospectively analyzed the procedure-induced complications, serial changes in ablated tumors, recurrence, and local as well as lymph node metastasis based on data obtained from medical records and radiological images. @*Results@#The mean follow-up period was 130.6 months (range 121–159 months). Three patients underwent a single RFA session, and two patients underwent two RFA sessions. We observed no procedure-induced complications. Three tumors completely disappeared after ablation, and ablation of the other two tumors resulted in the formation of a small scar that showed long-term stability (mean duration 16.8 months, range 12–27 months). At the last follow-up, no patient showed recurrence or lymph node metastasis, and serum thyroglobulin levels were within normal limits in all patients. @*Conclusion@#RFA may be effective and safe to treat low-risk PTMC in patients who refuse or are ineligible for surgery.

Radiofrequency Ablation of Papillary Thyroid Microcarcinoma: A 10-Year Follow-Up Study

Purpose@#To investigate the efficacy and safety of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) after > 10 years of follow-up. @*Materials and Methods@#This study included five patients who underwent RFA to treat PTMCs (five lesions, mean diameter 0.5 cm, range 0.4–0.7 cm) between November 2006 and December 2009. The inclusion criteria were histopathologically confirmed PTMCs, a single PTMC lesion without extrathyroidal extension, no metastasis, and ineligibility or refusal to undergo surgery. RFA was performed by a single radiologist using a radiofrequency generator and an internally cooled electrode. We retrospectively analyzed the procedure-induced complications, serial changes in ablated tumors, recurrence, and local as well as lymph node metastasis based on data obtained from medical records and radiological images. @*Results@#The mean follow-up period was 130.6 months (range 121–159 months). Three patients underwent a single RFA session, and two patients underwent two RFA sessions. We observed no procedure-induced complications. Three tumors completely disappeared after ablation, and ablation of the other two tumors resulted in the formation of a small scar that showed long-term stability (mean duration 16.8 months, range 12–27 months). At the last follow-up, no patient showed recurrence or lymph node metastasis, and serum thyroglobulin levels were within normal limits in all patients. @*Conclusion@#RFA may be effective and safe to treat low-risk PTMC in patients who refuse or are ineligible for surgery.

2021 Korean Thyroid Imaging Reporting and Data System and Imaging-Based Management of Thyroid Nodules: Korean Society of Thyroid Radiology Consensus Statement and Recommendations

Incidental thyroid nodules are commonly detected on ultrasonography (US). This has contributed to the rapidly rising incidence of low-risk papillary thyroid carcinoma over the last 20 years. The appropriate diagnosis and management of these patients is based on the risk factors related to the patients as well as the thyroid nodules. The Korean Society of Thyroid Radiology (KSThR) published consensus recommendations for US-based management of thyroid nodules in 2011 and revised them in 2016. These guidelines have been used as the standard guidelines in Korea. However, recent advances in the diagnosis and management of thyroid nodules have necessitated the revision of the original recommendations. The task force of the KSThR has revised the Korean Thyroid Imaging Reporting and Data System and recommendations for US lexicon, biopsy criteria, US criteria of extrathyroidal extension, optimal thyroid computed tomography protocol, and US follow-up of thyroid nodules before and after biopsy. The biopsy criteria were revised to reduce unnecessary biopsies for benign nodules while maintaining an appropriate sensitivity for the detection of malignant tumors in small (1–2 cm) thyroid nodules. The goal of these recommendations is to provide the optimal scientific evidence and expert opinion consensus regarding US-based diagnosis and management of thyroid nodules.

Pancreatic Neuroendocrine Tumor Presenting as Acute Pancreatitis / 대한소화기학회지

We report a case of acute pancreatitis secondary to pancreatic neuroendocrine tumor. A 46-year old man presented with upper abdominal pain. The serum amylase and lipase were elevated. Abdominal computed tomography (CT) and magnetic resonance cholangiopancreatography revealed a 1.7 cm sized mass at the pancreas body with a dilatation of the upstream pancreatic duct and mild infiltrations of peripancreatic fat. An endoscopic ultrasound-guided fine needle biopsy was performed for the pancreatic mass, but only necrotic tissue was observed on the pathologic examination. A chest and neck CT scan revealed anterior mediastinal, paratracheal, and cervical lymph node enlargement, which were indicative of metastasis. An ultrasound-guided core needle biopsy was performed for the enlarged neck lymph node, and pathologic examination revealed a metastatic poorly differentiated carcinoma. Immunohistochemical analysis showed positive staining for synaptophysin, chromogranin A, and CD 56, indicative of a neuroendocrine carcinoma.

Adult Intussusception Caused by Inverted Meckel's Diverticulum Containing Mesenteric Heterotopic Pancreas and Smooth Muscle Bundles

No abstract available.

Features of Pure Lobular Carcinoma In Situ on Magnetic Resonance Imaging Associated with Immediate Re-Excision after Lumpectomy / 한국유방암학회지

PURPOSE: To evaluate imaging features of pure lobular carcinoma in situ (LCIS) on magnetic resonance imaging (MRI) in patients who underwent immediate re-excision after lumpectomy. METHODS: Twenty-six patients (46.1±6.7 years) with 28 pure LCIS lesions, who underwent preoperative MRI and received curative surgery at our institution between 2005 and 2013, were included in this study. Clinicopathologic features associated with immediate re-excision were reviewed and analyzed using Fisher exact test or the Wilcoxon signed rank test. RESULTS: Of the 28 lesions, 21.4% (6/28, six patients) were subjected to immediate re-excision due to resection margin involvement by LCIS. Nonmass lesions and moderate-to-marked background parenchymal enhancement on MRI were more frequently found in the re-excision group than in the single operation group (100% [6/6] vs. 40.9% [9/22], p=0.018; 83.3% [5/6] vs. 31.8% [7/22], p=0.057, respectively). The median lesion size discrepancy observed between magnetic resonance images and histopathology was greater in the re-excision group than in the single operation group (-0.82 vs. 0.13, p=0.018). There were no differences in the mammographic or histopathologic findings between the two groups. CONCLUSION: Nonmass LCIS lesions or moderate-to-marked background parenchymal enhancements on MRI can result in an underestimation of the extent of the lesions and are associated with subsequent re-excision due to resection margin involvement.

Pretreatment Evaluation with Contrast-Enhanced Ultrasonography for Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas with Poor Conspicuity on Conventional Ultrasonography

OBJECTIVE: To determine whether pretreatment evaluation with contrast-enhanced ultrasonography (CEUS) is effective for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with poor conspicuity on conventional ultrasonography (US). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and informed consent was waived. From June 2008 to July 2011, 82 patients having HCCs (1.2 +/- 0.4 cm) with poor conspicuity on planning US for RFA were evaluated with CEUS prior to percutaneous RFA. We analyzed our database, radiologic reports, and US images in order to determine whether the location of HCC candidates on planning US coincide with that on CEUS. To avoid incomplete ablation, percutaneous RFA was performed only when HCC nodules were identified on CEUS. The rate of technical success was assessed. The cumulative rate of local tumor progression was estimated with the use of the Kaplan-Meier method (mean follow-up: 24.0 +/- 13.0 months). RESULTS: Among 82 patients, 73 (89%) HCCs were identified on CEUS, whereas 9 (11%) were not. Of 73 identifiable HCCs on CEUS, the location of HCC on planning US corresponded with that on CEUS in 64 (87.7%), whereas the location did not correspond in 9 (12.3%) HCCs. Technical success was achieved for all 73 identifiable HCCs on CEUS in a single (n = 72) or two (n = 1) RFA sessions. Cumulative rates of local tumor progression were estimated as 1.9% and 15.4% at 1 and 3 years, respectively. CONCLUSION: Pretreatment evaluation with CEUS is effective for percutaneous RFA of HCCs with poor conspicuity on conventional US.

The Efficacy of Unenhanced MR Imaging for the Diagnosis of Acute Appendicitis: A Performance Comparison Versus Abdominal Ultrasonography

PURPOSE: To evaluate the efficacy of unenhanced MR imaging compared to the diagnostic accuracy, advantage, and limitations of abdominal ultrasonography in the diagnosis of acute appendicitis. MATERIALS AND METHODS: The study included 40 patients suspected of having acute appendicitis and who were subjected to an unenhanced MR image, as well as an abdominal ultrasonography. A T1 FLASH in an axial image, a chemical shift-selective fat suppressed T2 HASTE in an axial image, as well as a T2 HASTE in an axial and coronal image were obtained as unenhanced MR images. The diagnosis was established based on a surgical or clinical follow-up of the unenhanced MR results, which were then statistically compared to the ultrasonographic results. RESULTS: The surgical or clinical follow-up results revealed that 25 patients were positively diagnosed with appendicitis. Of these, 7 patients had symptoms of acute appendicitis with no pathologic diagnoses, whereas the 8 remaining patients were diagnosed with another condition. The sensitivity and accuracy of the unenhanced MR imaging was 92% and 90%, compared to ultrasonography which was 68% and 72.5% accurate, respectively. The differences in sensitivity and accuracy between the two methods were found to be statistically significant (p < .05, chi-square test). Based on these results, unenhanced MR imaging was superior to sonography for the diagnosis of appendicitis. CONCLUSION: Unenhanced MR imaging may be a useful modality for the diagnosis of acute appendicitis, especially for suboptimal or nondiagnostic sonographies, as well as patients that are particularly sensitive to radiation exposure.

Enteroscopy-guided Contrast Radiography of Small Bowel Lesions

PURPOSE: To introduce the method of enteroscopy-guided contrast radiography (ECR) and evaluate the diagnostic value of ECR for those patients with small bowel lesions. MATERIALS AND METHODS: From Aug 2004 to Dec 2005, 43 double-balloon enteroscopy (DBE) examinations were performed in 32 patients with suspected small bowel diseases. Among them, DBE revealed abnormal finding in 24 patients, and ECR was then performed in 13 of these 24 patients. RESULTS: ECR demonstrated abnormal findings in 11 among the 13 patients. In the cases of tumors and bezoar, the ECR images were very helpful for the surgical planning. However, for the evaluation of inflammatory lesions, DBE showed more accurate results and ECR could not demonstrate small or shallow ulcerative lesions. CONCLUSION: ECR can be helpful for surgical planning or determination of treatment effect in the cases of small bowel lesions that require surgical treatment or follow-up study.

A Case of Dialysis-related Amyloidosis of the Hip and Cervical Spine: Imaging Findings

Dialysis-related amyloidosis is a complication of long-term hemodialysis and it is characterized by the accumulation of beta2-microglobulin in the osteoarticular structures. We describe here the imaging findings of a case of dialysis-related amyloidosis involving the hip and cervical spine in a 62-year-old woman who received long-term dialysis. We focus here on the CT and MR imaging findings of the cervical spine and we include a review of the relevant literatures.

MR Imaging Findings of Acute Gouty Arthritis

PURPOSE: The purpose of this study was to describe the clinical and MR imaging features of acute gouty arthritis and to define the characteristic findings that would be helpful for differentiating acute gouty arthritis from septic arthritis. MATERIALS AND METHODS: The authors retrospectively studied seven patients who suffered from acute gouty arthritis. The MR imaging findings were analyzed by two musculoskeletal radiologists who focused on joint effusion, subchondral bone erosion, bone marrow edema, synovial thickening (regular and even, or irregular and nodular), and the soft tissue changes (edema or abscess). The clinical records of the patients were reviewed with regard to age and gender, the clinical presentation and the laboratory findings (serum uric acid, WBC, erythrocyte sedimentation rate, C-reactive protein and synovial fluid culture). RESULTS: The patients consisted of six men and one woman whose mean age was 41 years (age range: 24-65 years). The joints involved were the knee (n=6), and ankle (n=1). Two patients had medical histories of gouty attacks that involved the first metatarsophalangeal joint. In six cases, the serum uric acid level during acute attacks was elevated. In all the patients, the affected joint became swollen, hot, erythematous and extremely tender, and this was accompanied by a high ESR and a high C-reactive protein level at the time of presentation. The results of Gram stain and culture of the synovial fluid were negative. In all patients, the MR images showed large amounts of joint effusion, thick irregular and nodular synovial thickening and soft tissue edema without subchondral bone erosions and soft tissue abscess. In one case, subchondral bone marrow edema of the medial femoral condyle was present. In five cases, there were multiple low signal foci in the joint on the spin-echo T2-weighted MR image. CONCLUSION: Even though the MR imaging findings of acute gouty arthritis are nonspecific, it should be considered as a possible diagnosis when a large amount of joint effusion, irregular and nodular synovial thickening and soft tissue edema without subchondral bone erosion, bone marrow edema or soft tissue abscess are seen in the knee or ankle joint, and especially if this is accompanied by the clinical and laboratory features of infection.

The relationship of adiponectin, leptin and ghrelin to insulin resistance and cardiovascular risk factors in human obesity / 대한내과학회지

BACKGROUND: Adiponectin, letin and ghrelin are considered to take part in the regulation of energy metabolism. We investigated the relationship between these adipokines and body mass index (BMI), regional adiposity, insulin resistance and cardiovascular risk factors in human. METHODS: Eighty six (Male : Female = 36 : 50, Age = 21-71 year old, BMI : 18 - 39.5 kg/m2) subjects without known medical problems participated in this study. Subjects were grouped based on BMI or visceral fat area (VFA) and gender. We measured lipid concentration, fasting glucose, fasting insulin, insulin resistance (HOMA-IR) and high sensitivity CRP (hsCRP). Body fat distribution was determined by computed tomography. Fasting serum adiponectin, leptin, and ghrelin were measured by ELISA. RESULTS: The group of BMI over 25 kg/m2 showed significant difference in waist circumference (WC), total fat area (TFA), subcutaneous fat area (SFA), VFA, Triglyceride (TG), hsCRP and leptin. Visceral fat dominant (VFD) group (VFA>or=100 cm2 or VFA/SFA>or=0.4) showed significant difference in age, BMI, WC, TFA, SFA, free fatty acid, HOMA-IR, hsCRP, adiponectin, leptin and ghrelin. Leptin was positively correlated with BMI, waist hip ratio (WHR), TFA, VFA, SFA, low-density lipoprotein cholesterol (LDL-C), HOMA-IR and fasting insulin. Adiponectin was negatively correlated with BMI, WHR, TFA, VFA, HOMA-IR and positively correlated with High-density lipoprotein cholesterol (HDL-C). Ghrelin level was negatively correlated with WHR, VFA, fasting glucose, HOMA-IR and positively correlated with HDL-C. And leptin was negatively correlated with ghrelin. As regional adiposity, SFA was positively correlated with leptin, and VFA was negatively correlated with adiponectin and ghrelin and positively correlated with leptin. CONCLUSIONS: This study demonstrated that VFA had more significant association with lipid metabolism and adipokine secretion than BMI and leptin levels were inversely correlated with ghrelin level.

Sclerosing Peritonitis with Gross Calcification: Case Report

Sclerosing peritonitis is an uncommon complication of continuous ambulatory peritoneal dialysis (CAPD) and can lead to small bowel dysfunction involving abdominal pain, progressive loss of ultrafiltration, and small intestinal obstruction. Peritoneal thickening, in which calcification can develop, often starts as a small plaque which gradually becomes larger. We report a case of CAPD-related calcifying peritonitis.

MRI Findings of the Brain in High-Voltage Electrical Burn Patient: Case Report

We report the delayed sequelae arising in a case of electrical injury, reviewing the literature on the subject and focusing on the MRI findings of the brain. A 23-year-old male suffered burns to the left parietal scalp, both feet, and the anterior chest wall. Neurological symptoms and MRI abnormalities appeared 14 days after the insult and continued for about three months. T1-weighted MR images demonstrated homogeneous hypointensity, while T2-weighted images depicted hyperintense finger-like projections. Contrast-enhanced T1-weighted images demonstrated strong band-like enhancement, indicating meningeal hyperemia. Follow-up MR imaging showed that the lesion had disappeared, indicating that the cerebral edema and meningeal hyperemia were reversible.

In-vivo Proton Magnetic Resonance Spectroscopy in Adnexal Lesions

OBJECTIVE: To explore the in-vivo 1H- MR spectral features of adnexal lesions and to characterize the spectral patterns of various pathologic entities. MATERIALS AND METHODS: Thirty-one patients with surgically and histopathologically confirmed adnexal lesions underwent short echo-time STEAM (stimulated echo acquisition method) 1H- MR spectroscopy, and the results obtained were analysed. RESULTS: The methylene present in fatty acid chains gave rise to a lipid peak of 1.3 ppm in the 1H- MR spectra of most malignant tumors and benign teratomas. This same peak was not observed, however, in the spectra of benign ovarian epithelial tumors: in a number of these, a peak of 5.2 ppm, due to the presence of the olefine group (-CH=CH-) was noted. The ratios of lipid peak at 1.3 ppm to water peak (lipid/water ratios) varied between disease groups, and in some benign teratomas was characteristically high. CONCLUSION: An intense lipid peak at 1.3 ppm is observed in malignant ovarian tumors but not in benign epithelial tumors. 1H- MRS may therefore be helpful in the differential diagnosis of adnexal lesions.

In vivo Proton MR Spectroscopic Findings of Focal Hepatic Lesions: Initial Experience

PURPOSE: To investigate the in vivo proton MRS features of various focal hepatic lesions and to distinguish these features according to the involved. MATERIALS AND METHODS: Twenty-five hepatic lesions [hepatocellular carcinoma (n=7), cholangiocarcinoma(n=3), metastatic tumor (n=9), hemangioma (n=3), hepatic abscess (n=2), lymphoma (n=1)] underwent proton MR spectroscopy using a 1.5T unit and a localized proton STEAM sequence, without respiratory interruption, The findings of this in-vivo sequence were then reviewed, with particular attention to the presence and location of dominant peaks. RESULTS: In-vivo proton MR spectra were successfully acquired in all cases. A dominant lipid peak appeared in the MR spectra of the hepatocellular carcinomas, metastatic tumors, hepatic abscesses, lymphoma, one hemangioma and one cholangiocarcinoma(88%) at 1.3ppm, but not in two cholangiocarcinomas and one hemangioma. The spectral peaks of other metabolites appeared very irregular and even different in the same disease. CONCLUSION: In focal hepatic lesions, the spectra obtained during in-vivo proton MRS were useful, and a lipid peak was most frequent and dominant. Among the various neoplasms there were, however, no specific MR spectral features, and nor did such features vary according to the specific pathologic entity.

Atypical Hepatic Angiomyolipoma: CT and MR Findings: A Case Report

Hepatic angiomyolipoma is a rare benign lipomatous tumor of the liver. Radiologic studies usually reveal a fat component, but since this may be minimal, such a component is not always detected. We report a case of atypical hepatic angiomyolipoma which because of the non-visualization of fat at CT and MR imaging, was difficult to differentiate from other hypervascular tumors.

Spiral CT in Kidney: Assumption of Renal Function by Objective Evaluation of Renal Cortical Enhancement

PURPOSE: To correlate the degree of renal cortical enhancement, objectively evaluated by means of spiral CT, with the serum level of creatinine, and to determine the extent to which this degree of enhancement may be used to detect renal parenchymal disease. MATERIALS AND METHODS: Eighty patients [M:F=50:30; age=25 -90 (mean, 53) years] with available serum level of creatinine who underwent spiral CT between September and October 1999 were included in this study. In fifty patients the findings suggested hepatic or biliary diseases such as hepatoma, biliary cancer, or stone, while in thirty, renal diseases such as cyst, hematoma, or stone appeared to be present. Spiral CT imaging of the cortical phase was obtained at 30 -40 seconds after the injection of 120 ml of non-ionic media at a rate of 3ml/sec. The degree of renal cortical enhancement was calculated by dividing the CT attenuation number of renal cortex at the level of the renal hilum by the CT attenuation number of aorta at the same level. The degree of renal cortical enhancement was compared with the serum level of creatinine, and the degree of renal cortical enhancement in renal parenchymal disease with that of the normal group. Among eighty patients there were five with renal parenchymal disease and 75 with normal renal function. RESULTS: The ratio of the CT attenuation number of renal cortex to that of aorta at the level of the renal hilum ranged between 0.49 and 0.99 (mean, 0.79; standard deviation, 0.15), while the serum level of creatinine ranged between 0.6 and 3.2 mg/dl. There was significant correlation (coefficient of -0.346) and a statistically significant probability of 0.002 between the ratio of the CT attenuation numbers and the serum level of creati-nine. There was a significant difference (statistically significant probability of less than 0.01) between those with renal parenchymal disease and the normal group. CONCLUSION: The use of spiral CT to measure the degree of renal cortical enhancement provides not only an effective index for estimating renal functional status but also a means of differentiating between patients with renal parenchymal disease and those who are normal.

Interdural Cyst of the Thoracolumbar Region

Spinal interdural cyst is an extremely rare lesion, the wall of which consists of a dura-like layer without arachnoid. This report describes two cases in which patients with interdural cysts of the thoracolumbar spine presented with atypical neurologic signs and symptoms, including lower back pain and radiating pian in both lower extremities. Plain radiographs, CT myelograms and magnetic resonance images were obtained, but the cysts could not be differentiated from extradural arachnoid cyst. Surgical intervention revealed a dura-like layer of cyst wall, and within the cyst, a fluid resembling cerebrospinal fluid was present. In one case, microscopic examination showed that fragments of connective tissue without an arachnoid lining formed a thin fibrous cystic wall, a finding consistent with meningeal cyst.

The Anterior Cruciate Ligament: The Value of Thin-section Proton Density Oblique Sagittal MR Imaging

PURPOSE: To evaluate the usefulness of thin-section proton density oblique sagittal MR imaging in the diagnosis of tear involving the anterior cruciate ligament (ACL). MATERIALS AND METHODS: In 61 arthroscopically confirmed cases (29 patients with ACL injury and 32 normal subjects), thin section proton-density images (TSPDI) were obtained and compared with conventional oblique sagittal PDI and T2-weighted images (T2WI). In TSPD imaging, the scan plane was parallel to the course of the ACL, based on a coronal scanogram; the parameters used were TR/TE 2000 msec/20 -33 msec, 2-mm slice thickness, 16 x16 cm FOV, 256 x192 matrix, two excitations, and no intersection gap. We evaluated the sensitivity and specificity of MR images for diagnosing ACL tear, and their quality, on the basis of whether or not they successfully visualised the anterior/posterior margin of the ACL and linear signal intensities within the ACL fascicles. We also investigated the effects of partial volume averaging between the proximal portion of the ACL and the lateral femoral condyle. RESULT: The sensitivity/specificity of TSPD imaging for diagnosing ACL tear were not significantly different from those of conventional oblique sagittal PDI and T2WI. In the ACL injury group, TSPDI was better in detecting increased signal intensity, ACL thickening, and visualization of torn ACL than conventional oblique sagittal PDI and T2WI. In normal subjects, image quality was constantly better on TSPDI than on conventional oblique sagittal PDI and T2WI. TSPDI clearly revealed the anterior margin in 31/32 cases (97%) and linear signal intensities within the ACL fascicles in all 32 (100%), and also markedly reduced the partial volume effect of the proximal ACL and lateral femoral condyle. CONCLUSION: In evaluating the ACL, the use of TSPD imaging is likely to lead to improved image quality. In addition, where routine MR imaging reveals indeterminate ACL injury, TSPDI can provide additional clues to diagnosis.