Real-time MRI may improve evaluation of dynamic dysfunction of the wrist
Click Here to Manage Email Alerts
Key takeaways:
- Reader assessment scores were higher in radial-ulnar deviation scans with higher resolutions.
- Static wrist MRIs were used to visualize wrist bones and triangular fibrocartilage complex anatomy.
Results published in The British Journal of Radiology showed use of a high-performance 0.55-Tesla MRI system may be feasible for imaging tissues of a moving wrist in real-time and may improve evaluation of dynamic dysfunction.
“These early results suggest that high-performance 0.55-Tesla MRI could be a promising technology to evaluate further for improving the assessment of wrist biomechanics and dynamic dysfunction,” the researchers wrote in the study.
Researchers categorized five healthy, asymptomatic participants (median age, 46 years) without a history of wrist trauma, wrist pain or prior wrist surgery to receive either real-time MRI and static MRI (n=3) or only static MRI (n=2) during wrist radial-ulnar deviation and clenched fist maneuvers. Outcome measures included image quality and reader assessment scores.
Researchers found higher reader assessment scores in radial-ulnar deviation scans with temporal resolutions less than 100 ms compared with images that had temporal resolutions greater than 100 ms. However, researchers found no differences between lower and higher temporal resolutions for the clenched fist maneuvers.
In addition, a slice thickness of 6 mm was associated with higher reader assessment scores compared with a slice thickness of 8 mm.
Researchers also found static wrist MRIs could be used to visualize wrist bones and triangular fibrocartilage complex anatomy.
“The resulting images, alongside static wrist MRI scans, present anatomical information relevant to assessing dynamic wrist dysfunction,” researchers wrote in the study. “The availability of this technique could provide means to address critical questions pertinent to wrist kinematics and dysfunction.”
They added, “Efforts to develop novel acquisition and image reconstruction for the high-performance 0.55-Tesla platform are underway, and these efforts could directly benefit wrist imaging.”
Perspective
Back to Top
The fact that we are approaching the ability to have moving MRI images is amazing, and the wrist is an area where we think about dynamic pathophysiology, so thinking about applying it there makes sense. The image quality in this preliminary report makes it clear this is not useful yet. The question is: Will it ever be useful?
There are a few thoughts. First, even static wrist pathophysiologies, such as scaphoid nonunion, scapholunate ligament insufficiency with fixed carpal malalignment and arthritis that can be associated with each, are associated with notable variation in levels of discomfort and incapability. That has always made me consider pathophysiology that may only be measurable on dynamic imaging — by definition much less severe pathophysiology — as pathophysiology that can be accommodated. Given that the pathophysiology is so slight and almost immeasurable, any surgical interventions would likely need to be compared to sham (placebo) surgery interventions to know if they are worthwhile.
Second, it is almost impossible to have a normal wrist MRI. Half of normal wrists have a ganglion cyst for instance. And by age 70 years, two-thirds of wrists have an articular disc signal abnormality. If we can achieve high-resolution dynamic MRI, we are going to be able to start to measure other aspects of anatomical variation and senescence.
Better imaging will only be useful to the degree that it can identify relevant, treatable pathophysiology that is not detectable by other means. The probability that will occur seems vanishingly small.
Collapse
Read more about
Click Here to Manage Email Alerts