Rate of growth divides focal lesions of bone into two classes which are largely mutually exclusive. Not all focal lesions require biopsy, and grading is especially helpful in deciding which should be biopsied and which may be safely followed. The statistical proof and logic of grading as an expression of growth rate are presented with a set of rules establishing each of the five grades in the presence of bone destruction. The radiologic signs necessary to establish rates are described and illustrated.
Eighty-two cases of neoplasms arising in Paget's disease of bone from the Mid-America Bone Tumor Registry, accessioned between 1958 and 1983, were reviewed. There were 77 osteosarcomas, 3 fibrosarcomas, 1 chondrosarcoma, and 1 giant cell tumor. The male/female ratio was 2:1. The age distribution was 18%, 29%, 36%, and 17% for the groups less than 51 years, 51-60 years, 61-70 years, and greater than 70 years, respectively. The femur was involved by tumor in 22%; the humerus in 21%; the pelvis in 21%; the calvarium in 12%; the tibia in 10%; and other bones in 15% of the cases. There were 48% survivors after 1 year; 17% after two; and 5% after three and five years; two additional patients with tumor lived for more than seven and 11 years. Radiographs available for simultaneous study in 43 cases revealed predominant tumor patterns that were mixed in 69%, osteoblastic in 21%, and osteolytic in 10%. Other radiographic data and the clinical and histopathologic data are in agreement with five earlier major studies. While the prognosis of neoplasms arising in Paget's disease generally is not good, a small fraction of long-term survivors after aggressive therapy makes this complication a challenge for timely radiographic diagnosis and histopathologic confirmation.
A method for directly measuring the reduction in diagnostic accuracy incurred by altering original radiographs was applied to evaluate a 35 mm film system. A total of 4,290 readings of 2,145 proved cases were collected. Analysis of the results indicate that the 35 mm system reduced diagnostic accuracy by about 2.3% +/- 2.4% at a 95% confidence level. The same method can be used to evaluate other photographic reduction systems, television displays, enhancement schemes, or even the importance of clinical data in roentgenographic interpretation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.