Christine B. Chung MD, Abstract Co-Author: Nothing to Disclose

Jerry Raphael Dwek MD, Presenter: Nothing to Disclose

Parvis Haghighi MD, Abstract Co-Author: Nothing to Disclose

Rakesh Puni, Abstract Co-Author: Nothing to Disclose

Graeme Mervyn Bydder MBChB, Abstract Co-Author: Nothing to Disclose

To qualitatively and quantitatively evaluate the deep layer of articular cartilage, a region not characterized by standard clinical MR imaging sequences, with Ultrashort TE(UTE) imaging.

Cadaveric knee specimens (n = 10) of the femorotibial and patellofemoral articulations were imaged with a 1.5 tesla clinical magnet equipped with UTE software. Imaging evaluation included standard T1-, and proton density-weighted fat-suppressed sequences in various imaging planes. UTE imaging was performed with TE times of 80 microseconds. Additional T1 and T2 measurements were obtained in both the femorotibial and patellofemoral compartment of each specimen. Specimens were subsequently sectioned into 3 mm slices and assessed both visually and by histologic analysis. MR images were retrospectively assessed in random fashion by 2 musculoskeletal radiologists working independently and blinded to gross and histologic analysis. In each specimen, the deep layer of cartilage was assessed with all imaging sequences and classified as normal or abnormal. Correlation with T1 and T2 measurements, as well as gross and histologic analysis was performed. Data analysis included McNemar statistics, the nonparametric Spearman rank test and Fisher’s exact test.

Standard clinical MR imaging sequences did not allow for accurate assessment of the deep layer of articular cartilage due to the gross disparity between T2 relaxation times in the more superficial versus deep layers of articular cartilage (millisecs versus microseconds). UTE imaging allowed for accurate qualitative and quantitative assessment of the deep layer of articular cartilage in both the femorotibial and patellofemoral cartilage.

UTE imaging may prove helpful for the evaluation of a region of articular cartilage, the deep layer, which has not been previously characterized by standard MR imaging sequences due to the variability in TE values encountered in articular cartilage.

Chung, C, Dwek, J, Haghighi, P, Puni, R, Bydder, G, Ultrashort TE Imaging Evaluation of the Femorotibial and Patellofemoral Cartilage of the Knee: Imaging Comparison with Histology in 10 Cadaveric Specimens to Establish the Normal and Pathologic MR Appearance of the Deep Layer of Articular Cartilage.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4412796.html