Biochemical T2* MR quantification of ankle arthrosis in pes cavovarus

Abstract

Pes cavovarus affects the ankle biomechanics and may lead to ankle arthrosis. Quantitative T2 STAR (T2*) magnetic resonance (MR) mapping allows high resolution of thin cartilage layers and quantitative grading of cartilage degeneration. Detection of ankle arthrosis using T2* mapping in cavovarus feet was evaluated. Eleven cavovarus patients with symptomatic ankle arthrosis (13 feet, mean age 55.6 years, group 1), 10 cavovarus patients with no or asymptomatic, mild ankle arthrosis (12 feet, mean age 41.8 years, group 2), and 11 controls without foot deformity (18 feet, mean age 29.8 years, group 3) had quantitative T2* MR mapping. Additional assessment included plain radiographs and the American Orthopaedic Foot and Ankle Society (AOFAS) score (groups 1 and 2 only). Mean global T2* relaxation time was significantly different between groups 1 and 2 (p = 0.001) and groups 1 and 3 (p = 0.017), but there was no significance for decreased global T2* values in group 2 compared to group 3 (p = 0.345). Compared to the medial compartment T2* values of the lateral compartment were significantly (p = 0.025) higher within group 1. T2* values in the medial ankle joint compartment of group 2 were significantly lower than those of group 1 (p = 0.019). Ankle arthrosis on plain radiographs and the AOFAS score correlated significantly with T2* values in the medial compartment of group 1 (p = 0.04 and 0.039, respectively). Biochemical, quantitative T2* MR mapping is likely effective to evaluate ankle arthrosis in cavovarus feet but further studies are required. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1562–1568, 2010

Disc Degeneration Assessed by Quantitative T2* (T2 Star) Correlated With Functional Lumbar Mechanics

“…Many of these techniques utilize the physics of water molecule relaxation within a magnetic field to produce images, which highlight the presence of proteoglycans (T1rho), hydration level (T2), and structure of the macromolecule matrix along with hydration level (T2*). Quantitative T2* (T2 star) mapping is an emerging technique with the added benefit of a short acquisition time, high signal-to-noise ratio, and three-dimensionality over traditional T2 mapping 11,17,18 . T2* has been shown to probe biochemical properties of the tissues and has been beneficial in cartilage 10,11,17–24 .…”

“…Quantitative T2* (T2 star) mapping is an emerging technique with the added benefit of a short acquisition time, high signal-to-noise ratio, and three-dimensionality over traditional T2 mapping 11,17,18 . T2* has been shown to probe biochemical properties of the tissues and has been beneficial in cartilage 10,11,17–24 . Specifically, T2* relaxation times provide information about spatial macromolecule architecture in conjunction with water molecule mobility 11,18 .…”

Axial T2* mapping in intervertebral discs: a new technique for assessment of intervertebral disc degeneration

“…T2* has also proven to be a reliable and valid method in biochemical cartilage imaging [14]. Few available studies imply a close relationship to T2; nevertheless, T2* seems to be more dependent on micro-structural tissue changes and has shorter imaging times providing the same spatial resolution; therefore T2* appears to be an adequate diagnostic method that can be implemented into a clinical MR protocol [15].…”

GRE T2*-Weighted MRI: Principles and Clinical Applications

“…Finally, it results in the relative increase of water content in the articular cartilage substrate [12, 48] and thus the T2* relaxation time will be extended. Several studies have shown that GRE T2*WI can be used to evaluate changes in the early articular cartilage degeneration of biological tissue structure with no obvious morphological changes [12, 49]. This has important clinical value for early articular cartilage degeneration.…”