Delayed gadolinium‐enhanced magnetic resonance imaging of cartilage (dGEMRIC) in Femoacetabular impingement

Abstract

Femoroacetabular impingement is a well-described pre-arthritic condition with two main types; cam and pincer. Studies using the open treatment for impingement have described patterns of articular cartilage wear specific to cam and pincer impingement. Assessing articular damage in the hip joint is an important component of treatment. Intravenous gadolidium allows radiologists to perform an indirect assessment of articular cartilage glycosaminoglycan (GAG) content by using a technique called dGEMRIC. Using this indirect assessment of articular cartilage, we compared the dGEMRIC indices in a group of six cam and seven pincer patients to a control group (n ¼ 12) of asymptomatic controls that had no plain MRI findings of osteoarthritis. The superior portion of the hip joint was divided into seven regions from 9 to 3 o'clock. These regions were then subdivided into peripheral and central regions. The cam and pincer groups both had statistically lower dGEMRIC values compared to the control group. The cam group demonstrated not only peripheral but also central involvement of the joint and this was concentrated in the anterior portion of the joint. The pincer group exhibited more global hip involvement with all areas of the hip averaging a dGEMRIC index 28% less than controls. With the use of dGEMRIC more specific patterns of cartilage wear can be elicited in patients with impingement, which may improve patient selection and help better understand the progression of osteoarthithis throughout the hip joint. ß

T1ρ Hip Cartilage Mapping in Assessing Patients With Cam Morphology: How Can We Optimize the Regions of Interest?

“…Mamisch et al [17], who used dGEMRIC in hips and described decreased T1 values in hips with cam-type deformity in the entire cartilage but especially in the anterosuperior quadrant, indicated loss of proteoglycan mainly in this region. Interestingly, the T1q prolongation was not only found in the lateral third of the anterosuperior cartilage, where the cam impingement occurs and the cartilage damage is expected, but also in the medial third in both the anterosuperior and posterosuperior quadrants.…”

Anterior Delayed Gadolinium-enhanced MRI of Cartilage Values Predict Joint Failure After Periacetabular Osteotomy

“…In FAI, global arthritic changes were noted in pincer-type hips and more anterior and central in cam-type hips [38]. In patients with FAI, with or without symptoms of impingement, higher alpha angle correlated with reduced dGEMRIC index on the anterosuperior aspect of the hip and more globally in patients with FAI with signs of impingement [58].…”

Automated segmentation and quantitative analysis of the hip joint from magnetic resonance images

“…The use of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) was first described by Bashir et al (1999) to allow the measurement of glycosaminoglycans (GAGs) loss from cartilage ECM in a quantitative manner, and therefore is quite commonly used for quantita- tive cartilage analyses (Bittersohl et al 2009;Lattanzi et al 2014;Mamisch et al 2011). In dGEMRIC, T1 relaxation time in cartilage is calculated after administration of a negatively charged contrast agent (Gd-DTPA 2− ) as an indirect measure of the loss of GAGs, which is considered as an early degenerative biochemical change that precedes any structural damage in the cartilage (Pritzker et al 2006).…”

“…More recently, dGEMRIC has proven to be accurate to detect cartilage damages in FAI patients with the promising intra-and inter-observer repeatability (the kappa coefficient 0.76 and 0.68) (Lattanzi et al 2014). Although dGEMRIC has been extensively validated (Bashir et al 1999;Bittersohl et al 2009;Lattanzi et al 2014;Mamisch et al 2011), it is still under discussion about how to best interpret dGEMRIC T1 maps to impact clinical decisions.…”

“…Quantitative assessment of cartilage using recent biochemical MR imaging techniques (e.g., dGEMRIC (Bittersohl et al 2009;Mamisch et al 2011), T1ρ (Carballido-Gamio et al 2008b), T2 (Nishii et al 2010;Watanabe et al 2007) and T2 * (Bittersohl et al 2012) mapping) also relies on the provision of ROIs, i.e., the segmentation volumes, to evaluate water, collagen and proteoglycan content of articular cartilages.…”