High-resolution magnetic resonance imaging and diffusion tensor imaging of the porcine temporomandibular joint disc

Abstract

Objectives: Diffusion tensor imaging (DTI) is an MRI modality for characterizing the property, microstructural organization and function in tissues such as the brain and spinal cord. Prior to this investigation, DTI had not been adapted for studies of the temporomandibular joint (TMJ) disc. Objectives were to test the feasibility of DTI to evaluate the porcine TMJ disc and to use DTI to observe differences in magnitude of anisotropy of water diffusion between TMJ disc regions. Methods: Five adult pig TMJs were scanned on a 9.4 Tesla horizontal bore MRI scanner using an inductively coupled surface coil. High-resolution gradient-echo and diffusionweighted spin-echo based images were obtained. The mean diffusivity and fractional anisotropy (FA) were computed in different regions of the disc. Two observers were calibrated to review the two-dimensional and three-dimensional images. Polarized light microscopy was used as the gold standard for collagen fibre orientation. Results: In the sagittal plane, the mean diffusivity was higher in the posterior (1.28¡0.10610 23 mm 22 s 21 ) and anterior (1.27¡0.08610 23 mm 22 s 21 ) bands compared with the intermediate zone (0.96¡0.01610 23 mm 22 s 21 ), and the FA index was also lowest in the intermediate zone. In the coronal plane, the mean diffusivity was higher in the medial (1.42¡0.01610 23 mm 22 s 21 ) and lateral (1.21¡0.12610 23 mm 22 s 21 ) aspects than in the centre (1.09¡0.08610 23 mm 22 s 21 ), and the FA index was also lowest in the centre. Conclusions: DTI is a useful method for non-invasively characterizing the structure/ property relationships of the porcine TMJ disc.

Relationship between anisotropic diffusion properties and tissue morphology in porcine TMJ disc

“…4). Similar results were also found by DTI measurements of 3D water diffusion in porcine TMJ discs 24 . However, the fractional anisotropy of water diffusion (0.36–0.55) in the DTI study was higher than the fluorescein diffusion (0.13–0.30) in this study.…”

“…, region dependent) 23 . A recent diffusion tensor imaging (DTI) study also showed the anisotropic and region-dependent behavior of water diffusion in porcine TMJ discs 24 .…”

Anisotropic Solute Diffusion Tensor in Porcine TMJ Discs Measured by FRAP with Spatial Fourier Analysis

“…16 Most recently, Benavides et al reported that there is a region-dependency of water diffusion in porcine TMJ disc using diffusion tensor MRI. 2 In the anteroposterior direction, the mean water diffusivity was higher in the anterior and posterior bands compared with the intermediate zone. In the mediolateral direction, the mean water diffusivity was higher in the medial and lateral aspects than in the center.…”

Computed tomography, cone beam computed tomography and magnetic resonance imaging diagnostic possibilities in dentistry

“…In the dental field a very promising novel approach is real-time imaging of TMJ movement by means of FLASH MRI [48]. Diffusion tensor imaging may in future provide another promising option for non-invasive diagnostics of microstructural soft tissue changes in the TMJ [49]. Apart from TMJ imaging, MRI has also been demonstrated to be useful for imaging of structures such as alveolar bone or teeth [51,52].…”

“…Another very modern concept seems to have great potential for TMJ imaging: diffusion tensor imaging (DTI). In an experimental study on pig cadavers Benavides et al [49] demonstrated that microstructural properties of the porcine TMJ disc as detected by proton diffusion could be useful for a non-invasive characterization of the disc.…”