3

The number of teslas in MRI scanners vary between 0.2 and 7 teslas, and sometimes even up to 10.5 Teslas (Siemens MAGNETOM 10.5T) and 11.7 teslas (Siemens MAGNETOM 11.7T).

Does the number of teslas matter when evaluating a tendinopathy with an MRI scanner?

I am mostly interested in epicondylitis (epicondylopathy).


Overall, 7T MRI show some promising results, but I couldn't find any study focusing on tendinopathies:

(1) seems to say that 7T MRI have some interesting potentials, but the study is quite old (2011) and focuses on the brain:

This review illustrates current applications and possible future directions of 7 Tesla (7 T) Magnetic Resonance Imaging (MRI) in the field of brain MRI, in clinical studies as well as clinical practice. With its higher signal-to-noise (SNR) and contrast-to-noise ratio (CNR) compared to lower field strengths, high resolution, contrast-rich images can be obtained of diverse pathologies, like multiple sclerosis (MS), brain tumours, aging-related changes and cerebrovascular diseases. In some of these diseases, additional pathophysiological information can be gained compared to lower field strengths. Because of clear depiction of small anatomical details, and higher lesion conspicuousness, earlier diagnosis and start of treatment of brain diseases may become possible. Furthermore, additional insight into the pathogenesis of brain diseases obtained with 7 T MRI could be the basis for new treatment developments. However, imaging at high field comes with several limitations, like inhomogeneous transmit fields, a higher specific absorption rate (SAR) and, currently, extensive contraindications for patient scanning. Future studies will be aimed at assessing the advantages and disadvantages of 7 T MRI over lower field strengths in light of clinical applications, specifically the additional diagnostic and prognostic value of 7 T MRI.

http://www.healthimaging.com/topics/diagnostic-imaging/7t-mri-sharpens-its-focus:

The sweet spot of 7T likely will fall in the few gaps left by its 1.5T and 3T siblings. For example, surgical planning for temporal lobe epilepsy seems to be an unmet need. “Current clinical imaging, 1.5T and 3T MRI, is pretty good at finding the most common pathology for temporal lobe epilepsy in a general way, but not at showing the exact extent of pathology,” says Thomas R. Henry, MD, a neurologist at University of Minnesota in Minneapolis.

http://www.massgeneral.org/research/researchlab.aspx?id=1438 :

An ultra-high-field 7-tesla MRI scanner capable of detecting subtle abnormalities that are not detectable by conventional MRI

(2):

As is evidenced by the images presented here, unique information relevant to various disease processes is currently available at 7T. There has been some hesitation in the past about clinical use of 7T, given concerns about whether traditional clinical information remained available despite changes in contrast, signal inhomogeneity, SAR limitations, etc. Here we demonstrate for a neuroimaging protocol that, with appropriate RF coils, pulse sequence modifications, and imaging protocol optimizations, 7T scanners may be used without losing most of the key clinical information content present in traditional imaging protocols at lower field strengths. This means that unique information of new clinical value may now be accessed without sacrificing routine clinical information. After a period of exploratory development, a portfolio of robust commercially-avalaible coils is now available for 7T use. Availability of self-shielded 7T scanner designs should facilitate incorporation into hospital settings, and ongoing work on 7T body imaging should continue to expand the list of indications for 7T imaging.

In summary, the tool of 7T MRI has been carefully tuned over the past several years. And increasingly, when we are asked the question ‘When will 7 Tesla scanners be ready for clinical use?’ we may finally respond: ‘Bring on the patients!’

mri-magnetom-7t-product_brochure-00277270.pdf:

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(3) is also quite old (2007):

High-field (3T) and ultra-high-field (UHF, 7T and above) systems are increasingly being used to explore potential musculoskeletal applications because they provide a high intrinsic signal-to-noise ratio (SNR), potentially higher resolution (spatial and temporal), and improved contrast. However, imaging at 7T and above presents certain challenges, such as homogeneous radiofrequency (RF) coil design, increased chemical shift artifacts, susceptibility artifacts, RF energy deposition, and changes in relaxation times compared to more typical clinical scanners (1.5 and 3T). Despite these issues, MRI at 7T likely will provide some excellent opportunities for high-resolution morphologic imaging and forays into functional imaging of musculoskeletal systems. In this review we address some of these issues and also demonstrate the feasibility of acquiring high-resolution in vivo images of the musculoskeletal system in healthy human volunteers at 7.0T. J. Magn. Reson. Imaging 2007.

(4) does mention the usefulness of high teslas for tendon analysis:

MRI of tendons and ligaments benefits from high spatial resolution. Stronger magnetic fields lead to higher signal-to-noise ratios and improvements in image resolution; for this reason, 3-T MRI may be more sensitive than 1.5 T for detection of partial thickness tears [26]. Alternatively, higher resolution may be achieved by using a local surface coil [27]. Imaging with shorter echo times improves sensitivity to tendon changes, although this may come at the expense of specificity [28,29]. T2 weighted images are helpful for identifying fluid signal in tendon or ligament tears (Figure 5) as well as for demonstrating changes in the surrounding tissues [30]. If the orientation of a tendon changes over its course, magic angle effects may be problematic; it may therefore be helpful to acquire images with a sufficiently long echo time to avoid these artefacts.


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