Year: 2008
Type: dissertation
Study design: Observational Study
Abstract: Background: Radiographic confirmation of diagnosis is important in all\ndiagnostic and classification criteria for spondyloarthropathy. The aim was to\nevaluate computed tomography (CT) and to compare it to radiography.\nMethods: A pilot study compared radiography and CT in 40 patients with\nspondyloarthropathy. A study on 1425 patients examined with CT, 910 of which\nalso with radiography, was reported in four papers. All CT examinations were\nreviewed and scored by two observers. The original outcomes from the radiography\nand CT examinations were obtained from the radiology reports.\nResults: CT had a higher sensitivity for sacroiliitis than radiography,\nespecially in early sacroiliitis. Radiography had a high rate of false negative and\nfalse positive outcomes.\nThe observer agreement between two observers in a large material was good,\nwhile the observer agreements between each of the observers and the original\nradiology reports were moderate. Intraobserver agreement for a smaller part of the\nmaterial for one of the observers was moderate.\nThere was a change in diagnosis in three of 126 patients (2.4%) examined\nmore than once from normal or equivocal to unilateral or bilateral sacroiliitis. Ten\nnormal cases had changed to equivocal (7.9%). In further six patients (4.8%) the\ndiagnosis advanced from unilateral to bilateral sacroiliitis. Four equivocal cases\nwere classified as normal on the second study, and one case of unilateral sacroiliitis\nwas classified as equivocal on the second study.\nMainly multiple or large erosions seem to be a valid solitary diagnostic sign.\nSmall solitary or few erosions need supplemental evidence from other inflammatory\nsigns such as sclerosis. Inflammatory sclerosis can frequently be distinguished from\ndegenerative sclerosis, and can sometimes support an early diagnosis, when\nerosions are not apparent. A practical CT classification for sacroiliitis consisting of\nno disease, suspect disease, and disease is proposed.\nConclusions: The clinical utility of conventional radiography for evaluation\nof sacroiliitis is low with a high rate of insufficient and false reports, making\nradiography unsuitable for clinical use or use in population studies. CT is a robust\nimaging method for suspected sacroiliitis with good observer agreement, with\nhigher rate of detection of sacroiliitis than radiography; also for early changes.\nThere is no use for repeat CT examinations for suspected sacroiliitis. The New York\ncriteria are unsuitable for use with CT and a new grading system for CT of\nsacroiliitis is proposed.
Author: Mats Geijer
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1602398364