Abstract
Objective: Bone scintigraphy is a highly sensitive method in the evaluation of sacroiliitis. Aim of this study is firstly to evaluate interobserver variation of partial and whole sacroiliac indicis, secondly investigation of clinical importance of these indicis in the diagnosis of sacroiliitis. Methods: Fourty-six subjects (24 female: 35.4±11.9; 22 male: 43.1±12.4) without sacroiliitis 45 subjects with low back pain (33 female: 43.3±11.5, 11 male: 35.5±17.2) were included in the study. For right (R) and left (L) whole indices (WSI) irregular region of interest (ROI), for partial indices superior (S) and inferior (I) rectangular ROI were used. For background activity, rectangular ROI was drawn from the sacral region. Indices were calculated from ratio of average counts of sacroiliac and background regions. Two independent observers calculated sacroiliac indices. Interobserver agreement was evaluated by Pearson analysis. Results: There was no significant interobserver difference (p>0.05). Significant correlation existed between all calculated indices. Among 45 patients with suspicion of sacroiliitis 15 had final diagnosis of sacroiliitis and all of the Tc-99m methilenediphosphonate planar and SPECT bone scintigraphy results of these patients were concordant with sacroiliitis. There were 8 false positive results in other 30 patients. Seven of these eight patients had normal index values. If the scintigraphy would be evaluated in conjuction with indicis the specificity would increase from 73% to 97% but sensitivity decreases from 100% to 80%. There was significant correlation between the observers calculated indicis (p<0.001).Conclusion: Superior and inferior sacroiliac index values can be used with confidence. If we use sacroiliac index values to confirm positive results; index values can increase the specificity of bone scintigraphy.
Highlights
IntroductionDifferential diagnosis of low back pain might be difficult, since it has a wide spectrum of etiologic causes and clinical differences in seronegative and sacroiliitis associated arthropathies
Low back pain is a common complaint in the public
Sagittal and transaxial slices of single-photon emission computed tomography (SPECT) images and three phase bone scintigraphy images were interpreted by five experienced nuclear medicine physicians who are aware of index values by visual interpretation
Summary
Differential diagnosis of low back pain might be difficult, since it has a wide spectrum of etiologic causes and clinical differences in seronegative and sacroiliitis associated arthropathies. Physical examination represents pain in sacroiliac joint projection after provocation maneuvers, as well as spondylarthropathies associated findings including peripheral arthritis, psoriatic lesions and uveitis. Bone scintigraphy is a sensitive, easy and cost effective imaging method in the diagnosis of sacroiliitis. Since there is physiological uptake in the sacroiliac joints it is hampered by this drawback as a diagnostic method and additive methods have been introduced in order to improve diagnostic power of bone scintigraphy. It has been demonstrated that the addition of quantitative methods (comparing the sacroiliac joint activity with background activity like sacrum) to bone scintigraphy has revealed increase in the sensitivity and has pointed the results in agreement with clinical findings [2]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
