Clinical diagnosis from digital displays: results and conclusions from the St Mary's evaluation project.

Preliminary results with the first commercially available digital display system to be installed in a British radiology department were published in 1989: these consisted of data from observer performance studies of digitized images displayed using a 1024-line monitor, showing a single pathological feature--subperiosteal resorption in renal osteodystrophy. Further experiments have now been conducted with the successor to this equipment, a 1280-line digital display system. Formal observer performance studies were undertaken for four pathological conditions, and the results show statistically significant differences in performance between the digitized displayed images and those on film. The display system was not considered to be good enough for the task of primary radiological diagnosis of subtle lesions; findings support the conclusion that careful, objective clinical evaluation of digital display systems is important before they are introduced into clinical use.

Clinical diagnosis from digital displays: preliminary findings of the St Mary's Evaluation Project.

Image quality is a fundamental issue in the introduction of picture archiving and communications systems (PACS), and one that has hitherto been eclipsed by other aspects of the considerable technological challenge facing scientists and manufacturers involved in its development. We conducted a formal evaluation of clinical radiological diagnosis from a commercially available PACS viewing station, using subperiosteal resorbtion in renal osteodystrophy as the test pathological diagnosis, with receiver operating characteristic (ROC) analysis of the results. We conclude that the displayed, digitised images were inferior to film using the apparatus tested and believe that careful, objective clinical evaluation of such systems is of paramount important.

Diagnosis of pelvic varicosities in women with chronic pelvic pain.

45 women with a history of lower-abdominal pain of more than 6 months' duration for which no obvious cause had been found during laparoscopy (pelvic-pain syndrome) were investigated with transuterine pelvic venography. For comparison venography was carried out on 10 women in whom pathology was considered to be a likely cause for their pain and 8 women admitted for tubal ligation and who had no pain. Pelvic varicosities and congestion unrelated to parity or the menstrual cycle were commonly found in women with the pelvic-pain syndrome. A score for quantifying the severity of the pelvic vascular abnormalities has been devised; a value of 5 or more gave a diagnostic sensitivity of 91% and a specificity of 89% for the pelvic-pain syndrome.

Evaluation of gallium-67 in the diagnosis of bronchial carcinoma.

Twenty-four patients with carcinoma of the bronchus had lung scans performed with gallium-67. The results were compared with corresponding chest radiographs. In four patients who had been treated with radiotherapy or cytotoxic drugs, there was no uptake of isotope in the lesion. The isotope, however, identified the neoplasm accurately in 17 out of the 20 cases (85%). The relative distribution of isotope in neoplastic tissue and adjacent inflammatory reaction is discussed as well as those cases in which either the radiograph or the scan failed to demonstrate the malignant lesion. Gallium scanning in this study failed to indicate the extension of growth into the mediastinal glands.