The purpose of this retrospective study was to compare the diagnostic value of four different imaging methods-computed tomography (CT), magnetic resonance (MR) imaging, ultrasonography (US), and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT-and their combined use for preoperative detection of cervical nodal metastases in head and neck squamous cell carcinoma (SCC). Sixty-seven patients (58 men and 9 women; mean age, 60.1 years) with head and neck SCCs underwent CT, MR, US, and PET/CT before surgery. First, each study was reviewed separately for the presence of nodal metastases. Then, the value of combined images was assessed based on a confidence rating score for each modality assigned by observers. These results were verified, on a level-by-level basis, with histopathologic findings. Histopathologic examination revealed nodal metastases in 74 of 402 nodal levels. The sensitivity, specificity, and accuracy were 77.0%, 99.4%, and 95.3% for CT and MR; 78.4%, 98.5%, and 94.8% for US; and 81.1%, 98.2%, and 95.0% for PET/CT, respectively. The comparison of these modalities showed no statistically significant difference among them (p > 0.05). The combination of CT, MR, US, and PET/CT improved sensitivity (86.5%), without loss of specificity (99.4%) and accuracy (97.0%), although the difference failed to reach statistical significance.

We found at least a 9.4% (15/160) prevalence of malignancy among ITN detected on CT. The further evaluation with US or biopsy should be performed, if an ITN shows CT features suggesting malignancy (calcification; AP/T ratio, >1.0; or mean attenuation value, >130 HU).

Our results suggest that MRI may be useful in the diagnosis of tailgut cyst. A multilocular cystic mass in the presacral space is a characteristic MRI finding of tailgut cyst, which may also be revealed as a cystic mass consisting of a large cyst accompanied by a small peripheral cyst. However, further studies are necessary to establish the usefulness of MRI for evaluating tailgut cysts.

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 ( 20, 21 50, or > 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.resentations at national and international meetings provide an important forum for the dissemination of current research findings to the scientific community. Subsequent publication in a scientific journal is the natural and final outcome of such presentations, where the investigation is subjected to exhaustive manuscript preparation, extensive analysis of results, and critical peer review process. The publication rate of presentations may be regarded as an indicator of the quality of the scientific research presented at the meeting (1 6) and of the country where the research was performed (7 9).However, the publication rate of presentations have ranged from 11% to 78% depending on medical specialty, with an average of 45% (1); these findings suggest that more than half of all abstracts are not fully published in scientific journals after

the combined analysis of CT, MR, and PET/CT can improve sensitivity in the detection of mandibular invasion by SCC of the oral cavity.