Esophageal Motility Disorders in Patients With Esophageal Barium Residue After Videofluoroscopic Swallowing Study.

OBJECTIVE: To investigate esophageal motility disorders in patients with esophageal residual barium on chest x-rays after videofluoroscopic swallowing studies (VFSS) through high-resolution esophageal manometry (HREM). METHODS: We reviewed the records of 432 patients who underwent VFSS from September 2019 to May 2021, and 85 patients (19.7%) with large residual barium (diameter ≥1 cm) were included. As a result of HREM, motility disorders were classified as major or minor motility disorders according. Esophagogastroduodenoscopy and chest computed tomography results available were also reviewed. RESULTS: Among 85 patients with large residual barium in the esophagus, 16 patients (18.8%) underwent HREM. Abnormal esophageal motilities were identified in 68.8% patient: three patients (18.8%) had major motility disorders-achalasia (n=1), esophagogastric junction (EGJ) outflow obstruction (n=2)-and eight patients (50%) had minor motility disorders-ineffective esophageal motility (n=7), fragmented peristalsis (n=1). In those with normal esophageal motility, three patients of esophageal structure disorders (18.8%)-esophageal cancer (n=1), cardiogenic dysphagia (n=1), slight narrowing without obstruction of EGJ (n=1)-and two patients (12.5%) with chronic atrophic gastritis (n=2) were confirmed. CONCLUSION: Esophageal motility disorders were identified in 68.8% of 16 patients with large esophageal residual barium with three patients in the major and eight patients in the minor categories. Residual barium in the esophagus was not rare and can be a sign of significant esophageal motility disorders.

Mediastinal Lymph Node Metastasis from Head and Neck Cancer: Predictive Factors and Imaging Features.

Purpose: To assess the predictive factors and describe the imaging features of mediastinal lymph node (MLN) metastases in patients with head and neck cancer. Materials and Methods: We compared the clinical features and disease characteristics (sex, age, site of primary tumor, histologic type, history of prior treatments, TNM stages, and metastasis in cervical LNs) of patients with head and neck cancers between the MLN metastasis and no MLN metastasis groups. We also evaluated the chest CT (distribution and maximum dimension of the largest LN) and PET/CT (maximum standardized uptake value) features of MLN metastases based on the MLN classification. Results: Of the 470 patients with head and neck cancer, 55 (11.7%) had MLN metastasis, involving 150 mediastinal stations. Hypopharynx cancer, recurrent tumor, T4 stage, N2/N3 stages, and M1 stage were found to be significant predicting factors for MLN metastasis. The most common location of MLN metastasis was ipsilateral station 2 (upper paratracheal LNs, 36.4%), followed by ipsilateral station 11 (interlobar LNs, 27.3%) and ipsilateral station 10 (hilar LNs, 25.5%). Conclusion: Metastasis to MLNs should be considered in patients with head and neck cancer, especially in cases that are associated with a hypopharyngeal cancer, recurrent tumor, and high TNM stages.

Comparison of diagnostic sensitivity of [18F]fluoroestradiol and [18F]fluorodeoxyglucose positron emission tomography/computed tomography for breast cancer recurrence in patients with a history of estrogen receptor-positive primary breast cancer.

BACKGROUND: To compare the diagnostic sensitivity of [18F]fluoroestradiol ([18F]FES) and [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) for breast cancer recurrence in patients with estrogen receptor (ER)-positive primary breast cancer. METHODS: Our database of consecutive patients enrolled in a previous prospective cohort study to assess [18F]FES PET/CT was reviewed to identify eligible patients who had ER-positive primary breast cancer with suspected first recurrence at presentation and who underwent [18F]FDG PET/CT. The sensitivity of qualitative [18F]FES and [18F]FDG PET/CT interpretations was assessed, comparing them with histological diagnoses. RESULTS: Of the 46 enrolled patients, 45 were confirmed as having recurrent breast cancer, while one was diagnosed with chronic granulomatous inflammation. Forty (89%) patients were ER-positive, four (9%) were ER-negative, and one (2%) patient did not undergo an ER assay. The sensitivity of [18F]FES PET/CT was 71.1% (32/45, 95% CI, 55.7-83.6), while that of [18F]FDG PET/CT was 80.0% (36/45, 95% CI, 65.4-90.4) with a threshold of positive interpretation, and 93.3% (42/45, 95% CI, 81.7-98.6) when a threshold of equivocal was used. There was no significant difference in sensitivity between [18F]FES and [18F]FDG PET/CT (P = 0.48) with a threshold of positive [18F]FDG uptake, but the sensitivity of [18F]FDG was significantly higher than [18F]FES (P = 0.013) with a threshold of equivocal [18F]FDG uptake. One patient with a benign lesion showed negative [18F]FES but positive [18F]FDG uptake. CONCLUSIONS: The restaging of patients who had ER-positive primary breast cancer and present with recurrent disease may include [18F]FES PET/CT as an initial test when standard imaging studies are equivocal or suspicious.

Characteristics of Patients With Esophageal Dysphagia Assessed by Chest X-Ray Imaging After Videofluoroscopic Swallowing Study.

OBJECTIVE: To evaluate the prevalence rate, types, characteristics, and associated factors of esophageal dysphagia detected on chest X-ray images after videofluoroscopic swallowing study (VFSS). METHODS: The medical records of 535 adults were reviewed retrospectively. Chest X-ray images taken after barium swallow study were analyzed and presence of any residual barium in the esophagus was considered as esophageal dysphagia. Esophageal dysphagia was classified based on the largest width of barium deposit (mild, <2 cm; severe ≥2 cm) and the anatomic level at which it was located (upper and lower esophagus). RESULTS: Esophageal residual barium on chest X-ray images was identified in 40 patients (7.5%, 40/535). Esophageal dysphagia was more frequent in individuals aged 65-79 years (odds ratio=4.78, p<0.05) than in those aged <65 years. Mild esophageal dysphagia was more frequent (n=32) than its severe form (n=8). Lower esophageal dysphagia was more frequent (n=31) than upper esophageal dysphagia (n=9). Esophageal residual barium in patients diagnosed with esophageal cancer or lung cancer was significantly associated with severe esophageal dysphagia (p<0.05) and at the upper esophagus level (p<0.01). CONCLUSION: Esophageal residual barium was observed on chest X-ray imaging after VFSS. Esophageal barium in the upper esophagus with a diameter of ≥2 cm is an important indicator of malignancy, and chest X-ray image taken after VFSS is an important step to evaluate the presence of esophageal disorder.

Intra-parotid lymph node metastasis in patients with non-cutaneous head and neck cancers: clinical and imaging features for differentiation from simultaneous parotid primary tumor.

BACKGROUND: Although uncommon, intra-parotid lymph node (IPLN) metastasis should be considered in the differential diagnosis of parotid masses in patients with head and neck cancers. PURPOSE: To compare the clinical and imaging features of IPLN metastases from head and neck cancers and simultaneous parotid primary tumors. MATERIAL AND METHODS: A retrospective review of 2199 patients with non-parotid head and neck cancers revealed 63 patients who also underwent parotidectomy during curative resection of head and neck cancer. After exclusion of direct extension to the parotid gland from adjacent primary tumors (n = 12) and IPLN metastases from skin cancer (n = 5), the final study group was composed of 46 patients, including 26 (1.2%) with 33 IPLN metastases and 20 (0.9%) with 24 simultaneous parotid primary tumors. We compared clinical features of patients (sex, age, site of primary tumor, histologic type, history of prior treatment for malignancy, TNM stages, side of parotid lesion, multiplicity, and metastasis in ipsilateral cervical LNs) and the CT (location in parotid gland, maximum dimension, margins, and central necrosis or cystic change) and 18F-FDG PET/CT (maximum standardized uptake value) findings. RESULTS: Ipsilateral level II LN metastasis was more frequent in the IPLN metastasis group than in the simultaneous parotid primary tumor group (73.1% vs. 35.0%, P < 0.05). Imaging features such as location in parotid gland, maximum dimension, margins, central necrosis or cystic change, and maximum standardized uptake value showed no significant differences between the two groups. CONCLUSION: CT and PET/CT findings of IPLN metastasis are indistinguishable from simultaneous parotid primary tumor in patients with head and neck cancers.

Top-cited articles versus top Altmetric articles in nuclear medicine: a comparative bibliometric analysis.

BACKGROUND: The impact of any scientific article has traditionally been measured by the number of citations received. More recently, alternative metrics (altmetrics) reflect the digital dissemination of knowledge across the online mediasphere. PURPOSE: To evaluate and compare the characteristics of top-cited articles with those of top Altmetric articles related to nuclear medicine (NM). MATERIAL AND METHODS: We performed a search of the Web of Science and Altmetric databases using 114 search terms to identify the 50 top-cited and 50 top Altmetric articles, respectively, in the field of NM. We then compared the following characteristics of the selected articles: publication type; journal category; country of origin; year of publication; topic; imaging modality; and accessibility. Chi-square tests were performed for statistical analysis. RESULTS: There were no overlaps between the 50 top-cited and 50 top Altmetric articles. In general, compared to the leading Altmetric articles in this field, the cited articles were: more frequently review works published in NM and radiology journals (76% vs. 13%, P = 0.000); published in or before 2005 (84% vs. 0%, P = 0.000); the majority were related to oncology (56% vs. 44%, P = 0.000); and originated from the Netherlands (12% vs. 0%, P = 0.000). Compared to the top-cited articles, the leading Altmetric articles were: more frequently original articles published in other clinical field journals (54% vs. 0%, P = 0.000); primarily published between 2016 and 2018 (70% vs. 0%, P = 0.000); focused on neurology (50% vs. 22%, P = 0.000); and originated from the UK (18% vs. 2%, P = 0.000). CONCLUSION: Citation counts and Altmetric scores represent unique perspectives for evaluating the impact of NM research.

Clinical Practice Guideline for Cardiac Rehabilitation in Korea.

BACKGROUND: Though clinical practice guidelines (CPGs) for cardiac rehabilitation (CR) are an effective and widely used treatment method worldwide, they are as yet not widely accepted in Korea. Given that cardiovascular disease is the second leading cause of death in Korea, it is urgent that CR programs be developed. In 2008, the Government of Korea implemented CR programs at 11 university hospitals as part of its Regional Cardio-Cerebrovascular Center Project, and 3 additional medical facilities will be added in 2019. In addition, owing to the promotion of CR nationwide and the introduction of CR insurance benefits, 40 medical institutions nationwide have begun CR programs even as a growing number of medical institutions are preparing to offer CR. The purpose of this research was to develop evidence-based CPGs to support CR implementation in Korea. METHODS: This study is based on an analysis of CPGs elsewhere in the world, an extensive literature search, a systematic analysis of multiple randomized control trials, and a CPG management, development, and assessment committee comprised of 33 authors-primarily rehabilitation specialists, cardiologists, and thoracic surgeons in 21 university hospitals and 2 general hospitals. Twelve consultants, primarily rehabilitation, sports medicine, and preventive medicine specialists, CPG experts, nurses, physical therapists, clinical nutritionists, and library and information experts participated in the research and development of these CPGs. After the draft guidelines were developed, 3 rounds of public hearings were held with staff members from relevant academic societies and stakeholders, after which the guidelines were further reviewed and modified. RESULTS: CR involves a more cost-effective use of healthcare resources relative to that of general treatments, and the exercise component of CR lowers cardiovascular mortality and readmission rates, regardless of the type of coronary heart disease and type and setting of CR. CONCLUSION: Individualized CR programs should be considered together with various factors, including differences in heart function and lifestyle, and doing so will boost participation and adherence with the CR program, ultimately meeting the final goals of the program, namely reducing the recurrence of myocardial infarction and mortality rates.

Diagnostic performance of CT, MRI, and their combined use for the assessment of the direct cranial or intracranial extension of malignant head and neck tumors.

BACKGROUND: Preoperative radiological evaluation of the cranial or intracranial extension of malignant head and neck tumors is critical in the planning of curative surgery. PURPOSE: To assess the diagnostic accuracy of computed tomography (CT) combined with magnetic resonance imaging (MRI), compared to CT or MRI alone in diagnosing the direct cranial or intracranial extension of malignant head and neck tumors, using histopathologic results as the reference standard. MATERIAL AND METHODS: CT and MRI images in 41 patients with malignant head and neck tumors abutting the skull were retrospectively reviewed. The images were evaluated for the presence or absence of skull invasion (erosion/destruction of the skull), dural invasion (nodular dural enhancement), and brain invasion (enhancing brain lesion with or without brain swelling/edema). The results of the CT alone, MRI alone, and CT combined with MRI were compared with the histopathologic findings. RESULTS: Of the 41 patients studied, ten had no invasion, eight had skull invasion, 17 had dural invasion, and six had brain invasion by tumor. The sensitivity/specificity/accuracy of CT alone, MRI alone, and CT combined with MRI for diagnosing intracranial extension were 78.0%/100%/94.5%, 85.4%/80.5%/93.9%, and 95.1%/100%/98.8%, respectively. The sensitivity of CT combined with MRI was significantly higher than those of CT alone ( P = 0.0156) and MRI alone ( P = 0.0313). CONCLUSION: CT combined with MRI is a more sensitive tool for the diagnosis of the direct cranial or intracranial extension of malignant head and neck tumors than CT alone and MRI alone.

Detection of loco-regional recurrence in malignant head and neck tumors: a comparison of CT, MRI, and FDG PET-CT.

BACKGROUND: The early and accurate detection of local or regional recurrence of head and neck tumor is critically important. PURPOSE: To compare the diagnostic accuracy of contrast-enhanced computed tomography (CT), contrast-enhanced magnetic resonance imaging (MRI), and fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT, alone and in combination, in detecting the locoregional recurrence of malignant head and neck tumor. MATERIAL AND METHODS: A total of 93 patients with loco-regional recurrence of malignant head and neck tumors underwent CT, MRI, and PET-CT within 30 days before surgery. CT, MRI, and PET-CT for each patient were retrospectively reviewed to determine the presence of recurrent tumors in the primary site on a patient-by-patient basis and that of regional lymph nodes on a level-by-level basis. The diagnostic accuracy of CT, MRI, and PET-CT, alone and combined, were accessed with the postoperative histopathological findings or with 12-month follow-up results as the standard of reference. RESULTS: The sensitivity/specificity/and accuracy of CT, MRI, and PET-CT for the detection of primary site recurrence was 89.9/85.7/89.3%, 94.9/85.7/93.6%, and 97.5/92.9/96.8%, respectively. The sensitivity/specificity/accuracy of CT, MRI, and PET-CT for the detection of nodal recurrence was 66.3/99.4/92.4%, 74.7/99.4/94.2%, and 85.5/94.9/93.0%, respectively. MRI + PET-CT achieved the best performance in the receiver operating characteristics curve analysis (Az value = 0.958 for primary site recurrence and 0.929 for nodal recurrence). CONCLUSION: MRI + PET-CT offered the highest diagnostic performance in the detection of loco-regional recurrence of malignant head and neck tumor, compared with CT, MRI, PET-CT, and other combinations including CT.

Effect of Nasogastric Tube on Aspiration Risk: Results from 147 Patients with Dysphagia and Literature Review.

Nasogastric tube (NGT) is a common feeding strategy for patients at risk of endotracheal aspiration with an oral diet. With NGT feeding, however, swallowing of small amounts saliva cannot be avoided. We investigated whether the aspiration rate when swallowing 1 mL of fluid increased in patients using an NGT in different dysphagia severities. One hundred forty-seven patients who had been receiving NGT feeding underwent a videofluoroscopic swallowing study (VFSS). During VFSS, subjects were offered 1 mL of fluid twice: initially, with the tube inserted (NGT-in) and, subsequently, with the tube removed (NGT-out). Aspiration depth was determined using the 8-point Penetration-Aspiration Scale (PAS) (0 points, no aspiration/penetration; 8 points, aspiration passing the vocal cords with no ejection efforts). PAS-diff was computed (PASNGT-in - PASNGT-out), and a positive PAS-diff (PAS-diff > 0) meant increased aspiration depth in the presence of NGT. After VFSS, diet recommendations were made according to dysphagia severity assessment: non-oral feeding (n = 59), diet modification (n = 74), and diet as tolerated (n = 13). Cognitive level (mini-mental state examination, MMSE) and general functional level (Modified Barthel Index, MBI) were compared between the PAS-diff > 0 and PAS-diff ≤ 0 groups. Aspiration severity did not significantly change after NGT removal (PASNGT-in, 2.45 ± 2.40; PASNGT-out, 2.57 ± 2.58; P = .50). Regardless of recommended diet, PAS-diff values were not significantly different (P = .49). MMSE and MBI were not significantly different (P = .23 and .94) between subjects with PAS-diff > 0 (n = 25) and PAS-diff ≤ 0 (n = 121). In conclusion, the risk of aspirating a small amount of fluid was not significantly different before and after NGT removal, regardless of swallowing function, cognitive level, or general functional level.

Intraobserver and Interobserver Variability in Ultrasound Measurements of Thyroid Nodules.

OBJECTIVES: The purpose of this study was to assess the intraobserver and interobserver variability in ultrasound (US) measurements of thyroid nodules. METHODS: We performed a prospective study of the US examinations of 73 patients with 122 thyroid nodules greater than 5 mm in size. Ultrasound measurements in 4 dimensions (anteroposterior, transverse, longitudinal, and maximum diameters) and measurement of the estimated volume (using the ellipsoid formula) of each thyroid nodule were performed twice by 2 independent radiologists (A and B, with 10 years and 6 months of experience, respectively). The intraobserver and interobserver variability in measurements of thyroid nodules was assessed by a Bland-Altman analysis of agreement. The absolute values for intraobserver and interobserver variability were compared by a paired t test. RESULTS: The 95% intraobserver and interobserver limits of agreement for the anteroposterior, transverse, longitudinal, and maximum diameters and estimated volume of thyroid nodules were ±18.2%, ± 14.3%, and ±21.0%; ± 17.2%%, ± 17.3%, and 18.2%; ± 14.6%, ± 15.5%, and ±22.3%; ± 13.8%, ± 15.5%, and ±19.6%; and ±30.2%, ± 27.7%, and ±44.1%, respectively. The absolute values for intraobserver variability were lower than those for interobserver variability for all measurements. CONCLUSIONS: There was considerable intraobserver and interobserver variability in US measurement of thyroid nodules, which must be taken into account during follow-up US examinations of patients with thyroid nodules.

Reliability and Validity of a New Method for Isometric Back Extensor Strength Evaluation Using A Hand-Held Dynamometer.

OBJECTIVE: To investigate the reliability and validity of a new method for isometric back extensor strength measurement using a portable dynamometer. METHODS: A chair equipped with a small portable dynamometer was designed (Power Track II Commander Muscle Tester). A total of 15 men (mean age, 34.8±7.5 years) and 15 women (mean age, 33.1±5.5 years) with no current back problems or previous history of back surgery were recruited. Subjects were asked to push the back of the chair while seated, and their isometric back extensor strength was measured by the portable dynamometer. Test-retest reliability was assessed with intraclass correlation coefficient (ICC). For the validity assessment, isometric back extensor strength of all subjects was measured by a widely used physical performance evaluation instrument, BTE PrimusRS system. The limit of agreement (LoA) from the Bland-Altman plot was evaluated between two methods. RESULTS: The test-retest reliability was excellent (ICC=0.82; 95% confidence interval, 0.65-0.91). The Bland-Altman plots demonstrated acceptable agreement between the two methods: the lower 95% LoA was -63.1 N and the upper 95% LoA was 61.1 N. CONCLUSION: This study shows that isometric back extensor strength measurement using a portable dynamometer has good reliability and validity.

The timing of bone SPECT to predict osteonecrosis after internal fixation of femur neck fractures.

BACKGROUND: Bone SPECT can be used after a femur neck fracture to assess the circulation of the femoral head in the immediate postoperative period because the blood supply is one of the major factors affecting bone uptake of radiotracer on bone scintigraphy. The purpose of our present study was to investigate whether osteonecrosis of the femoral head (OFH) after internal fixation of femoral neck fracture could be predicted by early and late bone SPECT. METHODS: This retrospective cohort study enrolled 44 patients (33 women; mean age, 66.9 years) who underwent surgical fixation for femoral neck fractures. Early and late bone SPECT images were obtained within 2 weeks postoperatively and at 3 months postoperatively. Patients were followed up for a minimum of 24 months (average, 34 months). RESULTS: OFH developed in 9 out of 44 patients but no patient showed nonunion. Seventeen patients with normal femoral head uptake on early bone SPECT were healed. Of 27 patients with decreased femoral head uptake on early bone SPECT, 2 patients developed OFH on radiography before 3 months postoperatively, 18 patients recovered to normal uptake on the late SPECT, and the remaining 7 patients still showed decreased uptake on the late SPECT at 3 months postoperatively. All of these 7 cases finally developed OFH on radiography. CONCLUSION: Bone SPECT can reliably predict the possibility of OFH with after femoral neck fracture at least 3 months after surgery, while early bone SPECT showed low specificity. STUDY DESIGN: Clinical.

Painful Intramuscular Lipoma of the Infraspinatus: Unusual Location and Presentation.

Intramuscular lipomas are considered a rare type of benign lipomas. They are usually located deeper and are less palpable than subcutaneous lipomas. A painful presentation with no palpable mass will make clinical diagnosis difficult; in these cases, further imaging should be considered. Only a small number of cases of intramuscular lipomas present with pain; these are located in the supraspinatus and deltoid muscles. To the authors' knowledge, there have been no previous reports of painful intramuscular lipomas involving the infraspinatus muscle. This article describes a case of intramuscular lipoma uniquely located in the infraspinatus muscle and presenting with shoulder pain. A 49-year-old woman presented with 2 months of left shoulder pain. There was no history of preceding trauma. Pain was aggravated by lying on the left shoulder and by the hand behind the back similar to Crass position. On the physical examination, her shoulder joint range of motion was slightly decreased. Simple radiography showed no significant abnormality, but ultrasonography revealed a hyperechogenic mass within the infraspinatus muscle. There was focal tenderness over the mass, but definite palpation of the mass was not possible. Magnetic resonance imaging revealed a well-circumscribed, homogeneous lesion measuring 43 × 28 × 16 mm within the infraspinatus muscle, leading to a diagnosis of intramuscular lipoma. Her pain was not improved with medication, suprascapular nerve block, and steroid injections. Finally, surgical intervention was done and intramuscular lipoma was confirmed by specimen. After excision, her shoulder pain was improved and resolved.

Incidental focal FDG uptake in the parotid glands on PET/CT in patients with head and neck malignancy.

OBJECTIVES: To evaluate the prevalence and clinical significance of focal parotid lesions identified by (18)F- FDG PET/CT in patients with nonparotid head and neck malignancies. METHODS: From 3,638 PET/CT examinations using (18)F-FDG conducted on 1,342 patients with nonparotid head and neck malignancies, we retrospectively identified patients showing incidental focal FDG uptake in the parotid glands. The diagnosis of parotid lesions was confirmed histopathologically or on imaging follow-up. Patient demographics, clinical features, maximum standardized uptake value (SUV(max)) on PET images, size and attenuation on corresponding contrast-enhanced CT images were assessed and correlated with the final diagnosis. RESULTS: The prevalence of incidental focal parotid FDG uptake on PET/CT was 2.1% (95% CI 1.4 - 3.0%). Among 21 patients with focal parotid lesions confirmed histologically or on imaging follow-up, 7 (33.3%) had malignant lesions (all metastases) and 14 (66.7%) had benign lesions (four pleomorphic adenomas, two Warthin's tumours, one benign lymph node, one granulomatous lesion, six lesions without histopathological confirmation). There were no significant differences in age, sex, SUV(max) or CT findings between patients with benign and those with malignant lesions. CONCLUSION: Focal parotid FDG uptake on PET/CT in patients with head and neck malignancy warrants further investigations to ensure adequate therapy for incidental parotid lesions. KEY POINTS: • The prevalence of parotid incidentaloma on PET in head and neck malignancy was 2.1% • The malignancy rate of incidental focal parotid FDG uptake was 33.3% • SUV max could not reliably differentiate malignant from benign incidental parotid lesions.

Usefulness of combined PET/CT to assess regional lymph node involvement in gastric cancer.

AIMS AND BACKGROUND: The aim of this study was to evaluate the value of positron emission tomography/computed tomography (PET/CT) for preoperative staging of gastric cancer and to compare the diagnostic performance of PET/CT with that of contrast-enhanced computed tomography (CECT). METHODS: We retrospectively reviewed 74 gastric cancer patients who underwent preoperative PET/CT and CECT, and subsequent curative surgical resection between April 2007 and July 2011. Preoperative PET/CT and CECT images for primary tumors of the stomach and lymph node metastases were reviewed retrospectively. The final diagnoses of primary tumors and LN metastases were based on histopathological specimens in all patients. RESULTS: Advanced gastric cancer was present in 65% of patients (n = 48), and the remaining patients had early gastric cancer (n = 26). Sixteen patients (22%) showed signet-ring-cell histology. For the detection of the primary tumor, the sensitivity of PET/CT was significantly higher than that of CECT (67% vs 55%, respectively; P = 0.049). For the evaluation of regional lymph node metastasis, the sensitivity, specificity, and accuracy of PET/CT and CECT were 34% and 51% (P = 0.065), 88% and 79% (P = 0.687), and 58% and 64% (P = 0.332), respectively. Neither PET/CT nor CECT detected regional lymph node metastases in early gastric cancer patients. Signet-ring-cell histology showed trends of non-FDG-avid lymph node metastases (odds ratio = 0.15, 95% confidence interval 0.17-1.37, P = 0.093). CONCLUSIONS: The accuracy of PET/CT is low and it is not a useful tool in the staging of gastric cancer overall in early gastric cancer and in signet-ring-cell carcinoma. Furthermore, the sensitivity of PET/CT could be inferior to that of CECT in the diagnosis of regional lymph node metastasis.

Characteristics and trends of research on positron emission tomography: a bibliometric analysis, 2002-2012.

OBJECTIVE: We performed a bibliometric analysis of scientific publications focused on positron emission tomography (PET) over a 10-year period. METHODS: The MEDLINE and ISI Web of Knowledge databases were searched for English language original articles focused on PET in SCI/SCIE-indexed journals in 2002, 2007, and 2012. We selected the documents with titles that included "PET" or "positron emission." The following information was obtained from each article: journal (year of publication, title, subject category, and impact factor), subspecialty, imaging modality used, tracer, species, sample size, number of authors, affiliation of the first author, declared funding, and country of origin. RESULTS: The yearly publication on PET increased from 547 (2002) to 986 (2007), and 1838 (2012). A total of 1753 (52.0%) articles were published in journals in the "Radiology, Nuclear Medicine & Medical Imaging" category, 1512 (44.9%) were in the subspecialty of oncology, 3245 (96.3%) used PET or PET/CT, 1698 (50.4%) used 2-fluoro-2-deoxy-D-glucose (FDG) as the radiotracer, 2378 (70.5%) were human studies, 1294 (38.4%) had a sample size of <20, 1674 (49.7%) had >7 authors, 779 (23.1%) were written by a first author from a department of nuclear medicine, and 1337 (39.7%) were supported by government funding. The United States published 948 studies (28.1%) followed by Japan (345, 10.2%) and Germany (335, 9.9%). In the time trend analysis oncology subspecialty, PET/MR as the imaging modality, FDG as the tracer, sample size>50, number of authors>7, radiology department affiliation of the first author, and government funding exhibited significantly positive trends. CONCLUSIONS: The number of publication concerning PET has increased rapidly over the last decade. This bibliometric analysis revealed characteristics and trends of current PET research that provides useful information to researchers.

Citation classics in radiology journals: the 100 top-cited articles, 1945-2012.

OBJECTIVE: The number of citations an article receives after its publication reflects its impact in the scientific community. The aim of this study was to identify and characterize the 100 top-cited articles published in radiology journals. MATERIALS AND METHODS: The top-cited articles published in 12 radiology journals were identified using the database of Science Citation Index Expanded (1945-2012). The 100 top-cited articles were selected and analyzed with regard to the number of citations, year of publication, publishing journal, authorship, institution and country of origin, type of article, radiologic subspecialty, main topic, and radiologic technique. RESULTS: The 100 top-cited articles were published in eight radiology journals, led by Radiology (n=67) and followed by the American Journal of Roentgenology (n=11). These articles were published between 1939 and 2006 with a mean of 664.3 citations per article (range, 371-6931). Seventy-eight articles were published after 1979, 57 originated from the United States, and 69 were original articles. The most common subspecialties of study were interventional radiology (n=19), neuroradiology (n=15), and breast imaging (n=11). The main topics of articles were radiofrequency ablation of hepatic tumors (n=9), followed by receiver operating characteristic curves (n=6). CONCLUSION: Our study presents a detailed list and analysis of the 100 top-cited articles published in radiology journals, which provides insight into historical developments in the field of radiology.

Incidental thyroid lesions identified by ultrasound in patients with non-thyroidal head and neck cancer.

BACKGROUND: Thyroid cancer is one of the common head and neck malignancies and may be found incidentally with other head and neck cancers. PURPOSE: To evaluate the prevalence and risk of malignancy in incidental thyroid lesions identified by ultrasound (US) in patients with head and neck cancer. MATERIAL AND METHODS: We retrospectively reviewed medical records of all patients with head and neck cancer other than of thyroid origin between January 2004 and December 2011. A total of 690 patients (537 men and 153 women; mean age, 58.9 ± 12.9 years) underwent US of the neck for the evaluation of cervical lymph node status (including thyroid gland). We evaluated the prevalence of patients with incidental thyroid lesions identified by US and the risk of malignancy in these patients. RESULTS: Of the 690 patients with head and neck cancer, 234 (33.9%) had incidental thyroid lesions on US. Based on US findings, 61 patients underwent fine-needle aspiration, with 39 eventually undergoing thyroidectomy. Among these thyroid lesions, 24 incidental thyroid lesions of 22 patients were histologically proven to be malignant (23 papillary and 1 follicular carcinomas). The risk of malignancy was 9.4% on a patient-by-patient basis. CONCLUSION: Screening of the thyroid gland should be included in the preoperative US examination for cervical lymph node metastases in patients with non-thyroidal head and neck cancer.

Where do radiologists publish their work? A comparative analysis of publications by radiologists in nonradiology journals in 2000 and 2010.

OBJECTIVE: We performed a comparative bibliometric study of the scientific publications by radiologists in radiology and nonradiology journals in 2000 and 2010. MATERIALS AND METHODS: A PubMed database search was conducted for all articles published by radiologists in journals indexed by Science Citation Index and Science Citation Index Expanded in 2000 and 2010 by using the search term "radiol*" or "imag*" in the first author's affiliation field. Subject categories and the impact factor (IF) of the publishing journal, which were based on information contained in the Institute for Scientific Information's Web of Knowledge Journal Citation Reports, were assigned to each article. We compared the number and proportion of articles published and the IF of radiology and nonradiology journals. RESULTS: Of the articles published by radiologists, 25.4% (1677/6598) in 2000 and 35.7% (4479/12,559) in 2010 were published in nonradiology journals. The articles were published in 552 and 1329 nonradiology journals in 2000 and 2010, respectively. The IFs of the nonradiology journals were significantly higher than those of the radiology journals (2.4 ± 3.0 vs 1.5 ± 1.2 in 2000 and 3.2 ± 3.8 vs 2.3 ± 1.4 in 2010; p < 0.0001). When we considered the subject categories, "Oncology," "Surgery," and "Neurosciences" accounted for the highest proportion of radiologic publications. CONCLUSION: Radiologic publications in nonradiology journals have increased in terms of number, percentage, journal IF, and range of contributions.