Acquired hyperostosis syndrome--AHYS--(sternocostoclavicular hyperostosis, pustulotic arthro-osteitis, SAPHO-syndrome): bone scintigraphy of the anterior chest wall.

The objective of this report is to provide a description of diagnostically significant scintigraphically recognizable sites and patterns of acquired hyperostosis syndrome (AHYS) on the anterior chest wall (ACW), which is involved in 82% of AHYS patients. In 49/90 of our own AHYS patients, planar bone scans of the ACW were performed with the gamma camera, applying an average of 650 MBq of 99mTc-phosphate complexes. In addition, 53 atraumatic patients with extrathoracic cancer were available for routine whole-body scintigraphy. None of these patients had increased uptake identifiable as metastasis clinically or by imaging modalities in either the ACW or the rest of the skeleton. The scintigraphic involvement of the various morphological ACW structures is described in AHYS. Moreover, attention is called to the diagnostic significance of focal hyperactivities at the anterior end of the 2nd-8th rib of adults, which are in the 5th place with respect to their frequency in AHYS. The diagnostic significance of sternocostal-joint involvement in AHYS can likewise be recognized by bone-scan scintigraphy and will be discussed. Bone scintigraphy is more sensitive than radiomorphological imaging in AHYS. This, however, only applies under three conditions. 1. The increased radiotracer uptake in the upper sternocostoclavicular region must be assessed on both the anterior and the posterior view of the ACW scan. 2. In addition to the anterior view of the routine scintiscan, further anterior scans with reduced scan time of the gamma camera are usually necessary. This ensures better visibility of the involvement of certain morphological structures that are important for AHYS diagnosis. Moreover, a statement can be made about the inflammatory ossifying activity/inactivity of the AHYS on ACW.3. Increased radionuclide uptake in the manubrium sterni and corpus sterni on the anterior scan should be verified by additional lateral or oblique scans of the thorax (sternum).