Development of a World Wide Web-based Interactive Education Program to Improve Detectability of Pulmonary Nodules on Chest Radiographs

PURPOSE: To design and develop a World Wide Web-based education program that will allow trainees to interactively learn and improve the diagnostic capability of detecting pulmonary nodules on chest radiographs. MATERIALS AND METHODS: Chest radiographs with known diagnosis were retrieved and selected from our institutional clinical archives. A database was constructed by sorting radiographs into three groups: normal, nodule, and false positive (i.e., nodule-like focal opacity). Each nodule was assigned with the degree of detectability: easy, intermediate, difficult, and likely missed. Nodules were characterized by their morphology (well-defined, ill-defined, irregular, faint) and by other associated pathologies or potentially obscuring structures. The Web site was organized into four sections: study, test, record and information. RESULTS: The Web site allowed a user interactively to undergo the training section appropriate to the user's diagnostic capability. The training was enhanced by means of clinical and other pertinent radiological findings included in the database. The outcome of the training was tested with clinical test radiographs that presented nodules or false positives with varying diagnostic difficulties. CONCLUSION: A Word Wide Web-based education program is a promising technique that would allow trainees to interactively learn and improve the diagnostic capability of detecting and characterizing pulmonary nodules.

MR Findings of Siliconoma in Interstitial Silicone Injection Mammoplasty Patients

PURPOSE: To assess the MR findings of siliconomas (silicone granulomas) in patients with interstitial silicone injection mammoplasty. MATERIALS AND METHODS: Women with interstitial silicone injection mammoplasty were referred for this study on the basis of clinical findings of palpable mass. Nine patients with 18 augmentated breasts underwent axial and sagittal MR imaging, and the results were analysed in terms of their size, shape, margin, signal intensity, enhancement pattern, distribution and adjacent parenchymal distortion. We undertook in-vitro MR imaging of silicone, paraffin, fat, and water, and then compared their signal intensities at each sequence. RESULTS: Siliconomas were seen as well-defined low-signal-intensity nodules at T1WI and high-signal-intensity nodules at T2WI. There was no demonstrable contrast enhancement. Where there was breast cancer in which heterogeneous signal intensity was observed at T1 -and T2WI, together with heterogeneous enhancement, siliconomas were well differentiated from the tumor mass. At in-vitro MR imaging of silicone, paraffin, fat and water, paraffin showed a very low signal intensitiy at all pulse sequences but silicone showed low signal intensity at T1-fat-suppressed T1WI and high signal intensity at T2-and water-suppressed T2WI. CONCLUSION: MRI allows clear differentiation of siliconoma from fat and fibroglandular tissue, and can therefore, reveal anatomical details and detect lesions in patients with interstitial silicone injection mammoplasty.

Central Lucency of Pelvic Phleboliths: Comparison of Plain Radiographs and Noncontrast Helical CT

PURPOSE: Central lucency of pelvic phleboliths is frequently observed on plain pelvic radiographs. When it is also present on noncontrast helical CT images, pelvic phleboliths may be easily diagnosed, with no suspicion of distal ureteral calculi. The objective of this study was to determine the frequency with which this phenome-non is seen on plain radiographs and noncontrast helical CT images. MATERIALS AND METHODS: During a recent two-year period we identified 70 patients with renal colic who under-went both abdomino-pelvic radiography and noncontrast helical CT scanning. Radiographs were obtained at 70 -85 kVp and 30 -40 mA; CT scans were preformed within one month of plain radiography with parameters of 120 kVp, 200 -220 mA, 5-mm collimation, and pitch of 1 -1.6, and using soft tissue and bone window settings. With regared to the central lucency of pelvic phleboliths, as seen on both on radiographs and CT im-ages, two experienced radiologists reached a consensus. RESULTS: Among the 70 patients, a total of 150 pelvic phleboliths was found. In all cases except one, pelvic radi-ography and noncontrast helical CT revealed the same number of phleboliths. The exception was a case in which one of two phleboliths demonstrated by CT was not seen on radiographs. Pelvic radiography revealed central lucency in 95 of these 150 phleboliths (63%), but noncontrast helical CT failed to depict a hypodense center in any phlebolith. CONCLUSION: Central lucency of pelvic phleboliths, as frequently seen on plain pelvic radiographs, was not revealed by routine noncontrast helical CT in any patient.The presence or absence of central lucency on these CT images cannot, therefore, be used to differentiate phleboliths from distal ureteral calculi.

Unilateral and Bilateral Lumbosacral Transitional Vertebrae: Comparison of the Incidence of Combined Diseases

PURPOSE: The purpose of this study was to evaluate the radiologic findings of lumbosacral transitional verte-brae (LSTV), as seen on plain radiographs and MRI, and to compare the incidence of combined diseases be-tween unilateral and bilateral groups. MATERIALS AND METHODS:We retrospectively evaluated the plain radiographs and MR images of 63 patients with LSTV, classifying its type according to Castellvi 's criteria, and evaluated disc herniations, facet joint os-teoarthritic change, scoliosis, and spondylolisthesis. We then compared the incidence of each combined diseases between unilateral and bilateral groups, and as a control group, 63 patients without LSTV were also eval-uated. RESULTS: Forty of 63 cases of LSTV (63.5%) were bilateral, and 23 (36.5%) unilateral. According to Castellvi 's criteria, the incidence of type I was 41.3% (unilateral 7 cases, bilateral 19), type III30.2% (unilateral 8 cases, bilateral 11), type II23.8% (unilateral 8 cases, bilateral 7), and type IV 4.8% (unilateral 0 cases, bilateral 3).With combined diseases, the incidence of disc herniation was 66.7% (unilateral 15 cases, bilateral 27), moderate to severe facet joint osteoarthritic change 28.6% (unilateral 11 cases, bilateral 7), scoliosis 27.0% (unilateral 9 cases, bilateral 8), and spondylolisthesis 9.5% (unilateral 2 cases, bilateral 4). The incidence of facet joint os-teoarthritic change was significantly higher in the unilateral group (47.8%) than in the bilateral group (17.5%) (p=0.02), and scoliosis occurred at a higher rate in the unilateral group (39.1%) than in the bilateral group (20.0%) (p=0.18). There was, however, no significant difference in the incidence of disc herniation and spondylolisthesis between the two groups (unilateral group: 65.2% and 8.7%; bilateral group: 67.5% and 10.0%, respectively). CONCLUSION: With LSTV, the incidence of facet joint osteoarthritic change was significantly higher in the unilat-eral group than in the bilateral group, and scoliosis also showed a higher rate of occurrence in the unilateral group.