Oral and maxillofacial radiology
Application of magnetic resonance T2 mapping in the temporomandibular joints

https://doi.org/10.1016/j.oooo.2012.05.025Get rights and content

Objectives

The objective of this study was to apply magnetic resonance (MR) T2 mapping to the normal temporomandibular joint (TMJ) disk and to determine its T2 character.

Study Design

Fourteen volunteers with 28 healthy TMJs were selected for this study. MR T2 maps of all of the disks were acquired. The global disk area and 6 zonal regions of interest (ROIs) of superior, inner, and inferior layers and anterior, middle, and posterior bands were defined for each disk. T2 values of the global disk and each zonal ROI were calculated. Comparisons of the T2 values among the 3 layers and among the 3 bands were performed using the general linear model.

Results

The T2 value for the whole disk was 40.21 ± 2.95. The T2 values of the superior (39.42 ± 3.73) and inferior layers (40.11 ± 3.29) were significantly higher than the inner layer (37.28 ± 3.54) (P < .05). The T2 values of the anterior (36.96 ± 3.43) and posterior bands (36.01 ± 3.72) were significantly lower than the middle band (41.04 ± 5.51) (P < .05).

Conclusions

Preliminary determinations of T2 values for the bands and layers of normal TMJ disks were calculated.

Section snippets

Material and Methods

Ethical approval for this prospective study was obtained from the ethical board of the West China College of Stomatology, Sichuan University, Chengdu, China. We declare that we have read the Helsinki Declaration and followed the guidelines in this investigation. Participation in the study was voluntary, and signed informed consent was obtained for all participants.

Results

Mean T2 values for the whole disk were 40.21 ± 2.95, and for the superior, inner, and inferior layers and anterior, middle, and posterior bands, the values were 39.42 ± 3.73, 37.28 ± 3.54, and 40.11 ± 3.29 and 36.96 ± 3.43, 41.04 ± 5.51, and 36.01 ± 3.72, respectively (shown in Table II). Significant differences were demonstrated among the 3 layers and among the 3 bands (P < .05) (shown in Table III). Post hoc tests found significantly higher T2 values in the superior and inferior layers

Discussion

Preliminary determinations of T2 values for the bands and layers of normal TMJ disks were calculated. The T2 characters of both top-down spatial variation and anterior-posterior spatial variation were documented.

The spatial variation of T2 values in healthy articular cartilage12, 13, 14 has been demonstrated to be related to different orientations of collagen fibers in different histologic layers of the cartilage or the magic-angle effect.5

In articular cartilage with different histologic

References (20)

There are more references available in the full text version of this article.

Cited by (0)

The present study was supported by the Science and Technology Department of Sichuan Province, Project No. 2010FZ0087.

View full text