Alberto Aliprandi MD, Abstract Co-Author: Nothing to Disclose

Luca Maria Sconfienza MD, Presenter: Nothing to Disclose

Stefania Tritella MD, Abstract Co-Author: Nothing to Disclose

Michele Bandirali MS, Abstract Co-Author: Nothing to Disclose

Pietro Randelli MD, Abstract Co-Author: Consultant, Biomet, Inc

Francesco Sardanelli MD, Abstract Co-Author: Consultant, Bracco Group

To evaluate whether the 3D DESS sequence improves the diagnostic performance obtained with the standard two-dimensional (2D) turbo spin-echo (TSE) T1- and T2-weighted fat-sat protocol, as compared with the arthroscopic standard of reference, in evaluating the rotator cuff lesions.

Fifty-seven patients underwent MR arthrography of the shoulder at 1.5 T (Sonata, Siemens) with three-plane fat-sat TSE T1-weighted and oblique coronal fat-sat T2-weighted standard sequences, followed by a 3D oblique coronal DESS sequence (TR, 20 ms; TE, 6 ms; partition thickness, 1.5 mm; matrix, 358x512). Rotator cuff lesions of the supraspinatus (SSP), infraspinatus (ISP) and subscapularis (SSC) muscles were classified using the Snyder’s criteria and compared with the arthroscopic standard of reference using the following four-point score: 0=incorrect diagnosis; 1=correct diagnosis with grade difference ≥2; 2=correct diagnosis with only one grade difference; 3=complete agreement. Two residents in Radiology with two and four years experience in musculoskeletal MR imaging independently evaluated TSE and DESS sequences (time interval=three months). We calculated the ratio between the observed total score and the maximal total score (3x57=171) as a measure of performance. Binomial and sign test were used.

Acquisition time was about 14 min for the TSE sequences and 5 min for the DESS sequence. The performance of the less experienced resident increased from 63% with TSE to 73% with DESS (P=.043) for the SSP, from 85% to 91% (P=.791) for the ISP, and from 84% to 88% (P=.289) for the SSC; for the more experienced resident, 81% to 82% (P=.424), 90% to 95% (P=.070) and 89% to 92% (P=.289), respectively.

Even though statistical significance was obtained only for the SSP evaluation by the less experienced resident, the volumetric DESS sequence always allowed a more accurate evaluation of the rotator cuff lesions in comparison with standard 2D TSE sequences.

The volumetric approach provided by 3D DESS is an interesting option for clinical MR arthrography of the shoulder, also taking into account the short acquisition time.

Aliprandi, A, Sconfienza, L, Tritella, S, Bandirali, M, Randelli, P, Sardanelli, F, Navigating the Three-dimensional (3D) Anatomy of the Rotator Cuff: Diagnostic Value of Double Echo Steady State (DESS) Sequence Applied to Magnetic Resonance (MR) Arthrography.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8016312.html