Efficacy and Safety of Radiofrequency Ablation for Benign Thyroid Nodules: A Prospective Multicenter Study

OBJECTIVE: To assess the efficacy and safety of thyroid radiofrequency (RF) ablation for benign thyroid nodules by trained radiologists according to a unified protocol in a multi-center study. MATERIALS AND METHODS: From 2010 to 2011, 345 nodules from 345 patients (M:F = 43:302; mean age ± SD = 46.0 ± 12.7 years, range = 15–79) who met eligibility criteria were enrolled from five institutions. At pre-ablation, the mean volume was 14.2 ± 13.2 mL (1.1–80.8 mL). For 12 months or longer after treatment, 276 lesions, consisting of 248 solid and 28 predominantly cystic nodules, were followed. All operators performed RF ablation with a cool-tip RF system and two standard techniques (a transisthmic approach and the moving-shot technique). Volume reduction at 12 months after RF ablation (the primary outcome), therapeutic success, improvement of symptoms as well as of cosmetic problems, and complications were evaluated. Multiple linear regression analysis was applied to identify factors that were independently predictive of volume reduction. RESULTS: The mean volume reduction at 12 months was 80.3% (n = 276) and at the 24-, 36-, 48-, and 60-month follow-ups 84.3% (n = 198), 89.2% (n = 128), 91.9% (n = 57), and 95.3% (n = 6), respectively. Our therapeutic success was 97.8%. Both mean symptom and cosmetic scores showed significant improvements (p < 0.001). The rate of major complications was 1.0% (3/276). Solidity and applied energy were independent factors that predicted volume reduction. CONCLUSION: Radiofrequency ablation performed by trained radiologists from multiple institutions using a unified protocol and similar devices was effective and safe for treating benign thyroid nodules.

Core Needle Biopsy of the Thyroid: 2016 Consensus Statement and Recommendations from Korean Society of Thyroid Radiology

Core needle biopsy (CNB) has been suggested as a complementary diagnostic method to fine-needle aspiration in patients with thyroid nodules. Many recent CNB studies have suggested a more advanced role for CNB, but there are still no guidelines on its use. Therefore, the Task Force Committee of the Korean Society of Thyroid Radiology has developed the present consensus statement and recommendations for the role of CNB in the diagnosis of thyroid nodules. These recommendations are based on evidence from the current literature and expert consensus.

Image Reporting and Characterization System for Ultrasound Features of Thyroid Nodules: Multicentric Korean Retrospective Study

OBJECTIVE: The objective of this retrospective study was to develop and validate a simple diagnostic prediction model by using ultrasound (US) features of thyroid nodules obtained from multicenter retrospective data. MATERIALS AND METHODS: Patient data were collected from 20 different institutions and the data included 2000 thyroid nodules from 1796 patients. For developing a diagnostic prediction model to estimate the malignant risk of thyroid nodules using suspicious malignant US features, we developed a training model in a subset of 1402 nodules from 1260 patients. Several suspicious malignant US features were evaluated to create the prediction model using a scoring tool. The scores for such US features were estimated by calculating odds ratios, and the risk score of malignancy for each thyroid nodule was defined as the sum of these individual scores. Later, we verified the usefulness of developed scoring system by applying into the remaining 598 nodules from 536 patients. RESULTS: Among 2000 tumors, 1268 were benign and 732 were malignant. In our multiple regression analysis models, the following US features were statistically significant for malignant nodules when using the training data set: hypoechogenicity, marked hypoechogenicity, non-parallel orientation, microlobulated or spiculated margin, ill-defined margins, and microcalcifications. The malignancy rate was 7.3% in thyroid nodules that did not have suspicious-malignant features on US. Area under the receiver operating characteristic (ROC) curve was 0.867, which shows that the US risk score help predict thyroid malignancy well. In the test data set, the malignancy rates were 6.2% in thyroid nodules without malignant features on US. Area under the ROC curve of the test set was 0.872 when using the prediction model. CONCLUSION: The predictor model using suspicious malignant US features may be helpful in risk stratification of thyroid nodules.

Erratum: Image Reporting and Characterization System for Ultrasound Features of Thyroid Nodules: Multicentric Korean Retrospective Study

On page 110, the author (Won-Jin Moon)'s affiliation has been incorrectly marked as 6Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University, Seoul 143-729, Korea. The correct affiliation is 5Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-729, Korea.

Core Needle Biopsy of Thyroid Nodules: Consensus Statement and Recommendations

Core needle biopsy is a complementary diagnostic method of fine needle aspiration for patients with thyroid nodules. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for diagnosis of thyroid nodules and recurrent thyroid cancers using core needle biopsy. These recommendations are based on evidence from the current literature and expert consensus.

Radiofrequency Ablation of Benign Thyroid Nodules and Recurrent Thyroid Cancers: Consensus Statement and Recommendations

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Radiofrequency Ablation of Benign Thyroid Nodules and Recurrent Thyroid Cancers: Consensus Statement and Recommendations

Radiofrequency ablation is a new non-surgical treatment modality for patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the treatment of benign thyroid nodules and recurrent thyroid cancers using radiofrequency ablation. These recommendations are based on evidence from the current literature and expert consensus.

Level of perception of changed lip protrusion and asymmetry of the lower facial height / 대한치과교정학회지

OBJECTIVE: While one of the most prevailing motivations for seeking orthodontic treatment is to achieve good facial esthetics, understanding the level of a person's perception to the changes that have occurred on the face after orthodontic treatment is critical to the process of orthodontic diagnosis and treatment planning. METHODS: 40 students attending art school participated in determining the level of their perception of changed lip position and facial asymmetry. Computer-graphic frontal face and facial profile photographs with balanced proportions were used to evaluate the level of a participant's perception of the changes in facial asymmetry and in lip position. RESULTS: Change of lip position over 2 mm and over a 3 mm change of facial asymmetry was perceived significantly. CONCLUSION: The results indicated that at least a 2 mm change of lip position was needed to be perceived after orthodontic treatment. The level of perception of the change in facial asymmetry was lower than that of the change in lip position. Information about facial changes given prior to the evaluation enhanced the level of perception.

Retrospective of the ICAO Activities for the Aviation Human Factors

No abstract available.

Orbital Blowout Fracture: MR Findings

PURPOSE: To access the usefulness of magnetic resonance(MR) in the evaluation of orbital blowout fracture. MATERIALS AND METHODS: Fourteen patients with orbital blow out fractures diagnosed by plain radiography(n = 8) or computed tomography(CT)(n = 6) were examined with MR. Twenty blowout fractures including six patients with two lesions were presented and the fracture site of the orbit was the medial wall in 11 cases and the orbital floor innine cases. MR images in nine cases of six patients could be compared with CT scans. On MR images, were trospectively evaluated the presence of fracture, herniation of orbital fat, abnormality of extraocular muscle, intraorbital hematoma and intrasinus hemorrhage. In nine cases we also compared these findings with CT scans. RESULTS: Eighteen orbital blowout fractures with fat herniation could be diagnosed on MR images. In only nine of these 18 cases, the fracture itself could be seen on MR images as a disruption of the orbital wall, which produce a signal void. But two blow out fractures without orbital fat herniation, seen on CT, were not detected on MRimages. Twenty abnormalities of extraocular muscle in 18 cases were depicted on MR images. There were nosignificant differences between MR and CT in the evaluation of orbital fat herniation and extraocular muscle abnormality ; however, in one case oblique sagittal MR images provided more useful information about the status ofthe inferior rectus muscle. Intraorbital hematoma was detected by MR in three patients. We were able to establish the presence of intraorbital hematoma by using the different signal intensities from fat or muscle on T1- and/or T2-weighted images. MR was found to be superior to CT in one case of intraorbital hematoma because of the iso-density of hematoma compared to muscle. MR also detected intrasinus hemorrhage which on T1-weighted images revealed high signal intensity in ten cases. MR was more valuable in demonstrating intrasinus hemorrhage in onecase where a CT scan showed only hypodense fluid. CONCLUSION: MR is a useful diagnostic modality in the evaluation of orbital blowout fracture with orbital fat herniation. Compared with CT, it also provides more valuable information about associated extraocular muscle abnormality, subacute hemorrhage in the orbit and paranasal sinus.

Radiological Findings of Vertebral Artery Dissection

PURPOSE: The vertebral artery dissection is rare and increasingly recognized as a source of stroke. The purpose of this study is to describe causes, clinical manifestations, MRI and anglographic findings. MATERIALS AND METHODS: Conventional anglograms(n=7) and magnetic resonance imaging(n=6) were retrospectively analyzed in seven patients of vertebral artery dissection. The classification of the Krayenbuhl and Yasargil for vertebral artery segmentation was used for localization of vertebral artery dissection. Additionally, etiology and clinical manifestations were also retrospectively reviewed. RESULTS: Six cases were spontaneous type and one case was traumatic type. The clinical diagnoses of 6 spontaneous arterial dissection cases were wallenberg syndrome(4 cases), subarachnoid hemorrhage(1 case), and infarction of the cerebellum corresponding to PICA territory(1 case). A linear bright signal caused by thrombus was well visualized at the dissection area on sagittal T1 weighted spin echo MR images in all 6 cases. The characteristic anglographic findings were profound narrowing in 4 cases, pearl and string sign(including dissecting aneurysm) in 3 cases, complete obstruction in 3 cases, and a double density lumen(true and false lumen) extending to proximal basilar artery in one case. Spontaneous dissections were located at the V4 segment in all 6 cases. One traumatic dissection was located at the V2 segment. CONCLUSION: The most common site of the spontaneous dissection of the vertebral artery was V4 portion and a linear bright signal caused by thrombus was well visualized on sagittal T1 weighted spin echo MR images.

Cervical Tuberculous Lymphadenitis: MR Features

PURPOSE: To characterize the magnetic resonance (MR) imaging features of cervical tuberculous lymphadenitis. MATERIALS AND METHODS: The cervical MR images of 14 patients with pathologically or clinically proven cervical tuberculous lymphadenitis were retrospectively analyzed. T1- and T2-weighted or proton density images and contrast enhanced MR images were obtained in all patients. RESULTS: Most patient had multiple (n=12), unilateral lesions (n=l0), 8 mm to 45 mm in size, round (n=46) or ovoid (n=46) in shape and all with smooth and well-defined margins mostly at internal jugular chain(N2: 41, N3: 2, N4: 21 ). The signal intensities of the most lymph nodes were isointense or slightly hyperintense on T1 -weighted images, and hyperintense (all) with variable homogeneity on T2-weighted and/or proton density images. After contrast enhancement most showed characteristic thin peripheral rim enhancement (n=71). CONCLUSION: The characteristic MR features of cervical tuberculous lymphadenitis would be multiple, unilateral enlarged lymph nodes which show iso or slightly increased signal intensity on T1 -weighted image, high signal intensity on T2-weighted and/or proton density image and peripheral rim enhancement.

Gastric Wall Shortening in Early Gastric Cancer: Upper Gastrointestinal Series and Pathologic Correlation

PURPOSE: To investigate the causes of gastric wall shortening in early gastric cancer, upper gastrointestinal study was correlated with pathologic findings. MATERIALS AND METHODS: We evaluated 41 cases(M :F=1.7:1, average age=49) of early gastric cancer, retrospectively. The gastric wall shortening were classified as Grade I; none, Grade II ;intermediate, and Grade III; prominent. Pathologic findings such as size of lesions, depth of tumor invasion, degree of the submucosal fibrosis, degree of thickness of the submucosa and muscularis propria, and morphologic patterns of lesions including conversing mucosal folds were correlated with the degree of gastric wall shortening on upper gastrointestinal series. RESULTS: Submucosal fibrosis was present in 4 cases in Grade I (n=21), 4 cases in Grade II (n=6) and 8 cases in Grade III (n=10). Positive conversing mucosal folds were seen in 5 cases in Grade I (n=17), 0 case in Grade II (n=2) and 9 cases in Grade III (n=9). Gastric wall shortening was significantly associated with submucosal fibrosis and conversing mucosal folds of early gastric cancer. (p=.0001 and p=.002, respectively) CONCLUSION: Upper gastrointestinal finding of gastric wall protrusion in patients with early gastric cancer should not misinterprete as advanced gastric cancer since the finding could be a result of submucosal fibrosis.

Gastric Wall Shortening in Early Gastric Cancer: Upper Gastrointestinal Series and Pathologic Correlation

PURPOSE: To investigate the causes of gastric wall shortening in early gastric cancer, upper gastrointestinal study was correlated with pathologic findings. MATERIALS AND METHODS: We evaluated 41 cases(M :F=1.7:1, average age=49) of early gastric cancer, retrospectively. The gastric wall shortening were classified as Grade I; none, Grade II ;intermediate, and Grade III; prominent. Pathologic findings such as size of lesions, depth of tumor invasion, degree of the submucosal fibrosis, degree of thickness of the submucosa and muscularis propria, and morphologic patterns of lesions including conversing mucosal folds were correlated with the degree of gastric wall shortening on upper gastrointestinal series. RESULTS: Submucosal fibrosis was present in 4 cases in Grade I (n=21), 4 cases in Grade II (n=6) and 8 cases in Grade III (n=10). Positive conversing mucosal folds were seen in 5 cases in Grade I (n=17), 0 case in Grade II (n=2) and 9 cases in Grade III (n=9). Gastric wall shortening was significantly associated with submucosal fibrosis and conversing mucosal folds of early gastric cancer. (p=.0001 and p=.002, respectively) CONCLUSION: Upper gastrointestinal finding of gastric wall protrusion in patients with early gastric cancer should not misinterprete as advanced gastric cancer since the finding could be a result of submucosal fibrosis.

Intracranial CT Angiography with Spiral CT: Preliminary Report

PURPOSE: The purpose of this study was to assess the usefulness of CT angiography(CTA) with spiral CT in evaluation of intracranial vascular lesions. MATERIALS AND METHODS: CTA and conventional angiography(CA) were performed in 22 patients with suspected intracranial vascular lesion. Nine patients had 10 aneurysms and 2 patients had arteriovenous malformation(AVM)s, while the remaining 11 patients had no vascular lesion. Twenty seconds after beginning injection of contrast media(100 mL with use of a power injector at the rate of 3 mL/sec), CT scanning(30-second continuous exposure and 60-mm length) was performed with a table speed of 2mm/sec and a section thickness of 2mm. The starting point was selected at the floor of the sella turcica. The resulting data were reformatted by MIP and SSD after reconstruction of 1 mm interval. For aneurysm, its size, shape, direction, neck and the relationship to adjacent vessels were compared to CA. RESULTS: The aneurysm diameter was ranged between 3mm and 20mm and all aneurysms were clearly visualized with CTA. CTA findings of the size, shape, direction, and neck of aneurysms and the relationship between aneurysm and adjacent vessels were well correlated with CA. In one case of aneurysm, calcification of the aneurysm wall was demonstrated on CTA. In one case of AVM, the nidus and its arterial supply and venous drainage were well visualized. In the other case of AVM, however, the feeding artery of AVM was not demonstrated on CTA(it was also unclear on CA). CONCLUSION: CTA with spiral CT may be useful in the evaluation of intracranial vascular lesion and valuable as a screening test for intracranial aneurysm.