Scientific Publications on Thyroid Ultrasound between 2001 and 2020: Differences in Research Characteristics by Disciplines

Objective@#To analyze the characteristics and trends of scientific publications on thyroid ultrasound (US) from 2001 to 2020, specifically examining the differences among disciplines. @*Materials and Methods@#The MEDLINE database was searched for scientific articles on thyroid US published between 2001 and 2020 using the PubMed online service. The evaluated parameters included year of publication, type of document, topic, funding, first author’s specialty, journal name, subject category, impact factor, and quartile ranking of the publishing journal, country, and language. Relationships between the first author’s specialty (radiology, internal medicine, surgery, otorhinolaryngology, and miscellaneous) and other parameters were analyzed. @*Results@#A total of 2917 thyroid US publications were published between 2001 and 2020, which followed an exponential growth pattern, with an annual growth rate of 11.6%. Radiology produced the most publications (n = 1290, 44.2%), followed by internal medicine (n = 716, 24.5%), surgery (n = 409, 14.0%), and otorhinolaryngology (n = 171, 5.9%). Otorhinolaryngology and internal medicine published significantly more case reports than radiology (p < 0.001, each). Radiology published a significantly higher proportion of publications on imaging diagnosis (p < 0.001 for all) and a significantly lower proportion of publications on biopsy (p < 0.001 for all) than the other disciplines. Publications produced by radiology authors were less frequently published in Q1 journals than those from other disciplines (p < 0.005 for internal medicine and miscellaneous disciplines and < 0.01 for surgery and otorhinolaryngology). China contributed the greatest number of publications (n = 622, 21.3%), followed by South Korea (n = 478, 16.4%) and the United States (n = 468, 16.0%). @*Conclusion@#Radiology produced the most publications for thyroid US than any other discipline. Radiology authors published more notably on imaging diagnosis compared to other topics and in journals with lower impact factors compared to authors in other disciplines.

Tracheal Bronchus with Persistent Pulmonary Hypertension of the Newborn: A Case Report

Tracheal bronchus is an uncommon anomaly in which an ectopic bronchus originates directly from the supracarinal trachea. It is usually an asymptomatic anatomical variant incidentally found on computed tomography or bronchoscopy. However, it can present with symptoms, such as chronic cough, wheezing, atelectasis, and recurrent pneumonia. We report a case of tracheal bronchus diagnosed in the neonatal period, in which the term baby presented with respiratory distress and persistent pulmonary hypertension of the newborn after birth, but no other congenital anomaly was found on further evaluation.

Harmonic ultrasonography for the detection of microlithiasis in the gallbladder

PURPOSE: To validate the use of harmonic ultrasonography (US) in the detection of gallbladder microlithiasis. METHODS: From November 30, 2012, to January 18, 2014, fundamental US (FUS) and harmonic US with a high background noise (HUS-N) were performed for evaluation of gallbladder during the routine abdomen US. During the US, a dot-like stone (or stones) with Brownian motion was regarded as a positive finding of microlithiasis. Fifty-five patients with microlithiasis in the gallbladder detected on US were enrolled as the subjects of a retrospective review. With respect to the obtained images, two abdominal radiologists independently scored the conspicuity of gallbladder microlithiasis on FUS and HUS-N by using a 4-grade scale. The statistical analysis employed a kappa test and a Wilcoxon rank-sum test. RESULTS: For FUS, the conspicuity grades of gallbladder microlithiasis were G1 in 25 and 37, G2 in 21 and 9, G3 in 6 and 6, G4 in 3 and 3 patients, while HUS-N showed G1 in 0 and 0, G2 in 3 and 2, G3 in 12 and 15, and G4 in 40 and 38 patients, respectively, by each of the two radiologists. The kappa value was 0.633 for FUS between the two radiologists and 0.708 for HUS-N. HUS-N showed better conspicuity of gallbladder microlithiasis than FUS with significant P-values of less than 0.001 and 0.001 for the two radiologists, respectively. CONCLUSION: Compared with FUS, HUS-N enables better detection of microlithiasis in the gallbladder.

Korea's Contribution to Radiological Research Included in Science Citation Index Expanded, 1986-2010

OBJECTIVE: To evaluate scientific papers published by Korean radiologists in the Science Citation Index Expanded (SCIE) radiology journals, between 1986 and 2010. MATERIALS AND METHODS: The Institute for Scientific Information Web of Knowledge-Web of Science (SCIE) database was searched for all articles published by Korean radiologists, in SCIE radiology journals, between 1986 and 2010. We performed the analysis by typing "Korea" and "radiol" in the address section and selecting the subject area of "Radiology, Nuclear Medicine, and Medical Imaging" with the use of the general search function of the software. Analyzed parameters included the total number of publications, document types, journals, and institutions. In addition, we analyzed where Korea ranks, compared to other countries, in terms of the number of published articles. All these data were analyzed according to five time periods: 1986-1990, 1991-1995, 1996-2000, 2001-2005, and 2006-2010. RESULTS: Overall, 4974 papers were published by Korean radiologists, in 99 different SCIE journals, between 1986 and 2010, of which 4237 (85.2%) were article-type papers. Of the total 115395 articles, worldwide, published in radiology journals, Korea's share was 3.7%, with an upward trend over time (p < 0.005). The journal with the highest number of articles was the American Journal of Roentgenology (n = 565, 13.3%). The institution which produced the highest number of publications was Seoul National University (n = 932, 22.0%). CONCLUSION: The number of scientific articles published by Korean radiologists in the SCIE radiology journals has increased significantly between 1986 and 2010. Korea was ranked 4th among countries contributing to radiology research during the last 5 years.

Calcified Carcinoma of the Gallbladder with Calcified Nodal Metastasis Presenting as a Porcelain Gallbladder: A Case Report / Journal of the Korean Cancer Association, 대한암학회지

Porcelain gallbladder is regarded as a risk factor of gallbladder cancer. A porcelain gallbladder with calcified regional lymph nodes was found using computed tomography (CT) and magnetic resonance imaging (MRI) in a 43-year-old man who presented with nausea, vomiting, and abdominal pain. His cholecystectomy specimen showed diffuse wall thickening and contained small gallstones. Histological examination revealed diffuse infiltrative adenocarcinoma with extensive intratumoral calcification (calcified carcinoma). The majority of the calcified material was located within or replaced the tumor glands, and was not found in the stroma. A lymph node was totally replaced with a calcified metastatic adenocarcinoma. To the best of our knowledge, only one case of calcified lymph node metastasis from a calcified carcinoma of the gallbladder has been previously reported in the literature. We herein add a case of calcified carcinoma of the gallbladder with calcified lymph node metastasis, presenting as a porcelain gallbladder on CT and MRI.

Angiomyofibroblastoma Arising from the Posterior Perivesical Space: a Case Report with MR Findings

Angiomyofibroblastoma is a rare benign soft tissue neoplasm that predominantly occurs in the genital region of middle-aged women. We present a case of an angiomyofibroblastoma that involved the posterior perivesical space in a 48-year-old woman. We have documented the magnetic resonance imaging features of this case.

Publication Rates for Abstracts Presented by Korean Investigators at Major Radiology Meetings

OBJECTIVE: To determine the publication rate of abstracts presented by Korean investigators at national and international radiological meetings, and to identify predictive factors of publication. MATERIALS AND METHODS: Abstracts presented at the annual meetings of the Korean Radiological Society (KRS), and abstracts presented by Korean investigators at the annual meetings of the Radiological Society of North America (RSNA) and European Congress of Radiology (ECR) from 2001 to 2002 were searched for subsequent publication, using PubMed and the Korean Medical Database. The following variables were evaluated. 1) The overall publication rate; 2) the publication rates according to the radiological subspecialty, presentation type (oral or poster), sample size ( 50), study design (prospective or retrospective), statistical analysis (present or absent), and study outcome (positive or negative); 3) the time to publication; 4) the journal where the study was published; 5) consistency between the abstract and the final publication. RESULTS: Of 1,097 abstracts, 301 (27.4%) were subsequently published, at an average of 15.8 +/- 13.8 months after presentation in 48 journals. The publication rates for studies presented at the RSNA (35.4%) and ECR (50.5%) conferences were significantly higher than that for the KRS conference (23.6%, p < 0.05). Vascular/interventional radiology studies had the highest publication rate (33.1%), whereas musculoskeletal radiology studies had the lowest publication rate (17.1%). Other factors associated with subsequent publication were prospective design, use of statistical testing, and a positive study outcome. CONCLUSION: The publication rate is significantly lower for the KRS (23.6%) meeting abstracts as compared to those of the RSNA (35.4%) and ECR (50.5%). Prospective design, use of statistical testing, and positive study outcome have a statistically significant effect on the publication rate.

Differentiation of Tuberculous Enteritis and Crohn's Disease with Barium Study Using Bayes Theory

PURPOSE: To differentiate tuberculous enteritis and Crohn's disease with barium study using Bayes theory. MATERIALS AND METHODS: The study group consisted of 34 patients with tuberculous enteritis (age range 16-86 years, mean age 43.3 years, M:F=19:15) and 36 patients with Crohn's disease (age range 19-78 years, mean age 35.2 years, M:F=18:18). These diagnoses were confirmed by therapeutic tests (tuberculous enteritis: 15, Crohn's disease:16) or histopathological examinations (tuberculous enteritis: 19, Crohn's disease: 20) conducted from January 1993 to May 2003. Three radiologists (two abdominal specialists and one trainee) analyzed each radiological finding of tuberculous enteritis and Crohn's disease by means of a barium enema and/or small bowel series. We used Fisher's exact test to verify the statistical significance of each radiological finding and p-values less than 0.05 were considered to be significant. We calculated the likelihood ratio (LR) of tuberculous enteritis versus Crohn's disease for each finding by employing Bayes theory. RESULTS: The radiological findings associated with a high likelihood ratio for tuberculous enteritis were the involvement of the cecum (LR=2.65) and ascending colon (LR=1.99), rigid narrowing (LR=1.94), shortening of the bowel (LR=1.99), haustral loss (LR=1.97) and sacculation (LR=3.88). The radiological findings associated with a high LR for Crohn's disease (low LR for tuberculous enteritis) were age between 20 and 29 years (LR=0.53), the involvement of the jejunum (LR=0.12), terminal ileum (LR=0.19), sigmoid colon (LR=0.30) or rectum (LR=0.17), and the presence of skip lesions (LR=0.19) or strictures (LR=0.21). With these LRs, the probability of the subject having tuberculous enteritis versus Crohn's disease could be calculated using Bayes theory. CONCLUSION: The analysis of a barium study using Bayes theory could provide an objective, easy and fast method of differentiating tuberculous enteritis and Crohn's disease.

MR Cholangiopancreatography: Comparison Between Single-Shot Turbo Spin-Echo Pulse Sequence and Three-Dimensional Turbo Spin-Echo Pulse Sequence with SENSE Technique

PURPOSE: To evaluate the relative image qualities obtained at magnetic resonance cholangiopancreatography (MRCP) turbo spin-echo (SSTSE) sequence and the three-dimensional turbo spin-echo (3D TSE) sequence with the sensitivity encoding (SENSE) technique. MATERIALS AND METHODS: Forty patients with suspected hepatic and extrahepatic diseases underwent MRCP using the SSTSE sequence and the 3D TSE sequence with the SENSE technique. Three radiologists scored and compared the quality of images of anatomic structures in the hepatopancreatic biliary system, and then directly compared the quality of the images obtained using the two sequences in each set of cases. RESULTS: For visualization of the intrahepatic bile duct, the cystic duct, the common bile duct, and the pancreatic duct, MRCP images obtained using the 3D TSE sequence with the SENSE technique were better than those obtained using the SSTSE sequence, though for the intrahepatic bile duct and common bile duct only, were these differences statistically significant (p<0.05). Quality was best for images of the common bile duct (87.5% for SSTSE and 97.5 % for 3D TSE with the SENSE technique). For the pancreatic and cystic duct, however, 52.5% and 10% of SSTSE images, respectively, and 57.5% and 32.5% of 3D TSE images, respectively, provided optimal image quality. In direct comparison, 3D TSE images obtained using the SENSE technique were better in 27 cases (67.5%), both images were equivocal in five cases (12.5%), and SSTSE images were better in eight cases (20%). These differences were statistically significant (p<0.05). CONCLUSION: For the visualization of anatomic structures in the hepatopancreatic biliary system, the 3D TSE sequence with the SENSE technique was better than the SSTSE sequence. For evaluation of the pancreatic and cystic duct, however, both techniques have their limitations and require further development.