The value of water-excitation 3D FLASH and fat-saturated PDw TSE MR imaging for detecting and grading articular cartilage lesions of the knee.
OBJECTIVE
To evaluate the diagnostic accuracy of water-excitation (WE) 3D FLASH and fat-saturated (FS) proton density-weighted (PDw) TSE MR imaging for detecting, grading, and sizing articular cartilage lesions of the knee.


METHODS
A total of 26 patients underwent MR imaging prior to arthroscopy with the following sequences: (1) WE 3D FLASH: 28/11 ms, scan time: 4 min 58 s, flip angle: 40 degrees; (2) FS PDw TSE: 3433/15 ms, scan time: 6 min 15 s, flip angle: 180 degrees. Grade and size of the detected lesions were quantified and compared with the results of arthroscopy for each compartment.


RESULTS
The sensitivity, specificity, positive and negative predictive values, and accuracy for detecting cartilage lesions were 46%, 92%, 81%, 71% and 74% for WE 3D FLASH and 91%, 98%, 96%, 94% and 95% for FS PDw TSE MR imaging. WE 3D FLASH correlated significantly with arthroscopy for grading on the patella ( P<0.0001) and the femoral trochlea ( P=0.02) and for sizing on the femoral trochlea ( P=0.03). FS PDw correlated significantly ( P<0.0001) with arthroscopy for grading and sizing on all compartments.


CONCLUSIONS
FS PDw TSE is an accurate method for detecting, grading and sizing articular cartilage lesions of the knee and yielded superior results relative to WE 3D FLASH MR imaging.
Department of Radiology, University of California San Francisco, 350 Parnassus Avenue, Suite 150, San Francisco, CA 94117-1349, USA. andreas.mohr@oarg.ucsf.edu
Andreas
A
Mohr
D000328:Adult; D001182:Arthroscopy; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007592:Joint Diseases / Q000175:diagnosis; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity