Delayed gadolinium‐enhanced magnetic resonance imaging (dGEMRIC) of hip joint cartilage in femoroacetabular impingement (FAI): Are pre‐ and postcontrast imaging both necessary?

The purpose of this study was to assess if delayed gadolinium MRI of cartilage using postcontrast T 1 ( T 1Gd ) is sufficient for evaluating cartilage damage in femoroacetabular impingement without using noncontrast values ( T 10 ). T 1Gd and Δ R 1 (1/ T 1Gd − 1/ T 10 ) that include noncontrast T 1 measurements were studied in two grades of osteoarthritis and in a control group of asymptomatic young‐adult volunteers. Differences between T 1Gd and Δ R 1 values for femoroacetabular impingement patients and volunteers were compared. There was a very high correlation between T 1Gd and Δ R 1 in all study groups. In the study cohort with Tonnis grade 0, correlation ( r ) was −0.95 and −0.89 with Tonnis grade 1 and −0.88 in asymptomatic volunteers, being statistically significant ( P < 0.001) for all groups. For both T 1Gd and Δ R 1 , a statistically significant difference was noted between patients and control group. Significant difference was also noted for both T 1Gd and Δ R 1 between the patients with Tonnis grade 0 osteoarthritis and those with grade 1 changes. Our results prove a linear correlation between T 1Gd and Δ R 1 , suggesting that T 1Gd assessment is sufficient for the clinical utility of delayed gadolinium MRI of cartilage in this setting and additional time‐consuming T 10 evaluation may not be needed. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.