Evaluation of magnetic resonance imaging relaxation time in wrist cartilage with scapholunate ligament injury

Abstract

Objective: The overall goal of this research is to identify completely non-invasive in vivo markers of cartilage degeneration following wrist injury in order to facilitate assessment and treatment of wrist injuries and prevention of osteoarthritis as a result of injury. In this study, the transverse relaxation time, T2, from magnetic resonance imaging (MRI) of the wrist cartilage of subjects exhibiting unilateral scapholunate dissociation was analyzed to evaluate changes in the biochemical status of the cartilage in the wrist following injury.Methods: Data collection consisted of MRI scans of the wrist using 2 separate 3T scanners. Fourteen subjects were analyzed, each subject completed scans to evaluate T2 relaxation times on both their injured and contralateral (normal) wrist. Scans were conducted with a maximum of 0.390625 mm/pixel in-plane pixel size and 1 mm slice thickness. A series of four time echo scans ranging from 15-80 ms were collected. T2 relaxation time for each subject was calculated by registering these echo time scans and fitting the corresponding intensity values to an exponential decay curve. Results:The T2 results from all subjects indicated no statistically significant changes with presence of injury. The use of two separate MRI scanners of the same strength of magnet coil did not cause a significant change in measurement values. Conclusions:Our data suggests that either T2 relaxation time does not change with the presence of scapholunate injury in the wrist or that the change was insufficient to be detected in this study. The results from this study may function as a baseline for future studies examining the potential positive effect surgical repair has on T2 relaxation times.

Effects of Scapholunate Ligament Injury and Surgical Repair on Wrist Cartilage T2 Relaxation Time

“…Prior work in our laboratory focussed solely on normal and injured (pre-op) wrists and, with a larger number of subjects, was unable to find statistically significant differences between the T2 relaxation times of the normal and injured wrist. 5 Even so, it was unexpected to find no statistically significant changes in T2 relaxation time. Although this may appear to suggest that there is not a change in T2 value with respect to injury in the wrist, it is also possible that our scanner capabilities were unable to accurately record the change.…”