Ab1804

Colour Doppler ultrasonography to detect pannus in knee joint synovitis

W.A. Schmidt¹, L. Völker², J. Zacher³, M. Schläfke³, M. Ruhnke⁴, E. Gromnica-Ihle¹

¹Medical Centre for Rheumatology, Berlin-Buch; and the ²Department of Ultrasonography, ³Department of Orthopaedic Surgery, and ⁴Department of Pathology, Klinikum Buch, Berlin, Germany.

ABSTRACT
Objective
To determine if colour Doppler ultrasonography can characterise the nature of intraarticular echogenic structures and synovial villi more precisely than conventional ultrasonography.

Methods
This is a prospective study on 20 patients - 10 with rheumatoid arthritis and 10 with osteoarthritis. Colour Doppler ultrasonography of the knee joints was performed prior to total prosthetic replacement. Two independent, trained physician ultrasonographers examined the knee to be replaced with different ultrasound equipment using colour Doppler and power Doppler ultrasonography. The existence and extent of pannus were then assessed surgically and histologically.

Results
All 9 patients with histologically detected pannus had perfused, echogenic, intraarticular structures (ultrasonographer 2; ultrasonographer 1: 8 out of 9 patients). Sparse perfusion was detected in 1 patient (investigator 1) and in 5 patients (investigator 2) with extensive non-destructive synovial proliferation. Colour Doppler and power Doppler ultrasonography were equivalent in detecting small intraarticular vessels.

Conclusion
Colour Doppler ultrasonography improves the differentiation of intraarticular structures compared to conventional ultrasonography.

Key words
Ultrasonography, color Doppler ultrasonography, power Doppler ultrasonography, rheumatoid arthritis, osteoarthritis, knee joint, knee surgery, synovitis, pannus.

Please address correspondence and reprint requests to: Wolfgang A. Schmidt, M.D., Medical Centre for Rheumatology, Berlin-Buch, Zepernicker Strasse 1, 13125 Berlin-Buch, Germany.
E-mail: schmidt.wa@t-online.de