|ECR 2011 / C-1439|
|Evaluation of meniscal lesions with high field (1.5 T) and new concept dedicated (0.31 T) MR systems: imaging findings and correlation with arthroscopy|
Arthroscopy was taken as the gold standard concerning presence (value of "1") or absence (value of "0") of meniscal lesions.
For each meniscus anterior and posterior horns were considered, with the following scores: 0, absence of lesion; 1, uncertain interpretation; 2a, degenerative lesion; 2b, complete fracture and/or parameniscal cyst and/or bucket handle lesion. In order to evaluate both Readers' sensitivity and specificity while operating with both systems we considered the "0" score as absence of meniscal lesion and the "1, 2a, 2b" scores as presence of meniscal lesion.
Reader’s A sensitivity and specificity were 59% and 92.1% for the dedicated MR system and 62.5% and 100% for the high field one, respectively.
Reader’s B sensitivity and specificity were 54.5% and 94.7% for the 0.31 T MR scanner and 59% and 94.7% for the high field one, respectively (Figure 1).
Furthermore we evaluated both Reader's sensitivity and specificity for the posterior horn of the medial meniscus (Figure 1); we considered the PHMM because, according to literature, it is the most affected area in traumatic knee injuries. In our study we found a lesion of the AHMM (anterior horn of the medial meniscus) in 26.7% of cases, of the PHMM in 93.3% of cases, of the AHLM (anterior horn of the lateral meniscus) and of the PHLM (posterior horn of the lateral meniscus) in 13.3% of cases.
For the PHMM Reader's A sensitivity and specificity were 71.4% and 100% for the dedicated MR system and 92.8% and 100% for the high field one, respectively.
For the PHMM Reader's B sensitivity and specificity were 78.6% and 100% for the 0.31 T MR scanner and 85.7% and 100% for the high field one, respectively.
We considered the "1" score (uncertain interpretation) as presence of meniscal lesion because of the low number of negative arthroscopic findings in order to better compare MR results with the gold standard.
Thematically related posters
ECR 2011 / C-2224
Diagnostic usefulness of dynamic contrast-enhanced magnetic resonance imaging for assessment of infection in the joints; preliminary results
ECR 2011 / C-0613
Antero-superior impingement (ASI) of the shoulder related to rotator interval lesions: arthro-MRI accuracy versus arthroscopy