Radiographic Findings of Primary Lung Cancer with Delayed Detection on Chest Radiographs

PURPOSE: To analyze the causes of delayed detection of lung cancer on chest radiographs. MATERIALS AND METHODS: We retrospectively reviewed 105 cases in which an initial diagnosis of lung cancer, based on anexamination of plain radiographs, had been missed or misinterpreted. All occurred between October 1993 and April1997. We reviewed the initial chest radiographs and compared the features noted with those seen on later chestradiographs and computed tomographic (CT) images. RESULTS: Undetected lung cancer was identified in 56 patients(56/105, 53.3%) It had been hidden by superim-posed structures (41, 73.2%), overlapped by combined benign diseases(12, 21.4%), or the nodules were subtle(3, 5.4%). Of the 41 lung cancers hidden by a superimposed structure, thecentral type accounted for 29 (70.7%) and the peripheral type for 12 (29.3%). The 29 central type had been hiddenby the left hilum (n=15), the right hilum (n=10), the heart (n=3), or a rib (n=1). The twelve peripheral type werehidden by a rib (n=7), the heart (n=2), the diaphragm (n=2), or the left hilum (n=1). Of the 12 lung cancersoverlapped by combined benign diseases, pulmonary tuberculosis (n=6), pleural effusion (n=4), congestive heartfailure (n=1), and dif-fuse interstitial lung disease (n=1) were present at the time of interpretation. Themisinterpreted lung cancers were identified in 49 patients (49/105, 46.7%) and were seen to be combined withbenign disease (16, 32.6%), or as obstructive pneumonia without a central mass (15, 30.6%), air-spaceconsolidation (7, 14.3%), cavity (7, 14.3%), double lesion (2, 4.1%), or young age below 26 years (2, 4.1%). Ofthe 16 lung cancers misinterpreted as combined disease, pulmonary tuberculosis (n=14) and pleural disease (n=2)had been initially diagnosed. CONCLUSION: Most commonly, lung cancer was missed or misinterpreted because it washidden by a normal structure or combined with a benign disease. Perceptual errors can be reduced by appropriatetechniques and the scrutiny of trouble spots such as the parahilar, retrocardiac, retrodiaphragmatic and costalregions. Errors in the analysis of lung cancer can be reduced by increased awareness of growth patterns anduncommon man-ifestations of the disease.

CT Findings of the Pulmonary Tuberculosis in Patients with Diabetes Mellitus

PURPOSE: To evaluate the CT findings of pulmonary tuberculosis in patients with diabetes mellitus (MD),according to the diabetic control state. MATERIALS AND METHODS: We retrospectively studied 34 cases of pulmonarytuberculosis accompanied by DM. We divided the right lung three lobes and ten segments and the left into two lobesand eight segments and analyzed CT findings of bronchogenic spread, cavitary lesion, ill-defined nodule, lobularconsolidation, lobar and segmental consolidation, atelectasis, interlobular septal thickening, fibrotic band, andassociated findings such as lymph node enlargement, pleural effusion and empyema. We also tried to determine thetypical CT findings of pulmonary tuberculosis according to diabetic duration and controlled state of DM focusingby FBS 160 and HbA1C 8.0. RESULT: Among 34 CT scans, bronchogenic spread was seen on 29 (85.3%), cavitary lesionon 26 (76.5%), ill-defined nodules on 11 (32.4%), lobular consolidation on 14 (41.2%), lobar and segmentalconsolidation on 12 (35.3%), atelectasis on four (14.7%), and fibrotic band on eight (23.5%). Multiple cavitieswere present in 76.9% of total cavitary lesions, and consolidation with bronchogenic spread in 75%; associatedfindings were as follows: lymph node enlargement (n=1), pleural effusion (n=10), empyema (n=2), and pericardialeffusion (n=2). In 46.7% of cases, general tubercular lesions were in an unusual location, but among cases ofsecondary pulmonary tuberculosis, 73.9% of lesions were in the usual location. More lobular consolidation was seenin patients with less than FBS 160 on admission, and this result was statistically significant (p<0.05); CTfindings did not, however, differ according to diabetic duration and HbA1C. CONCLUSION: In patients with DM,general fubercular lesions were found infrequently, but in secondary tubereulosis, multiple cavitary lesions-inthe usual location-were very frequent. In patients with DM, CT findings of pulmonary tuberculosis did not varyaccording to the diabetic control state, except that in patients with less than FBS 160 on admission, there was agreater degree of lobular consolidation.

Usefulness of Turbo Spin-Echo MR Imaging in Meniscal Tears of the Knee

PURPOSE: To evaluate the usefulness and diagnostic accuracy of turbo spin-echo(TSE) proton-density andT2-weighted images of meniscal tears of the knee. MATERIALS AND METHODS: We retrospectively evaluated thesensitivity, specificity, and accuracy of TSE proton density and T2-weighted images of meniscal tears confirmedarthroscopically or surgically in 47 patients(98 menisci). The routine TSE parameters used in all patients werethe dual echo sequence with sagittal proton density and T2-weighed images(4000/16, 90/5/2 [TR/effectiveTE/ETL/NEX]), and fat-suppressed coronal proton density and T2-weighted images. The chi-square test was used forstatistical analysis. RESULTS: The sensitivity, specificity, and accuracy of TSE proton density images for thedetection of meniscal tears were 93.9%, 93.8%, and 93.9%, respectively, in the medial meniscus, and 92.9%, 91.4%,and 91.8% in the lateral. On T2-weighted images the corresponding figures were 87.9%, 93.8%, and 89.8%,respectively, in the medial meniscus, and 64.3%, 91.4%, and 83.7 % in the lateral. CONCLUSION: With regard tosensitivity and accuracy, TSE proton density images of meniscal tears were superior to TSE T2-weighted images.

Dumbbell-shaped Epidural Cavernous Hemangioma: A Case Report

It has been reported that cavernous hemangiomas in the spine are generally located in vertebral bodies. Wereport a case of epidural cavernous hemangioma, a very rare condition, at the C7-T2 level. MR images showed adumbbell-shaped mass, with iso and high signal intensity on T1- and T2-weighted images, respectively. The mass wasintensely enhanced following Gd-DTPA injection.