Magnetization Transfer Contrast on Gradient Echo MR Imaging of the Temporomandibular Joint

1995 ◽  
Vol 36 (3) ◽  
pp. 295-299 ◽  
Author(s):  
M. Niitsu ◽  
H. Hirohata ◽  
H. Yoshioka ◽  
I. Anno ◽  
N. G. Campeau ◽  
...  
Keyword(s):  
Magnetization Transfer ◽  
Mouth Opening ◽  
Receiver Coil ◽  
Gradient Echo ◽  
Magnetization Transfer Contrast ◽  
Signal Suppression ◽  
Temporomandibular Joints ◽  
Opening And Closing ◽  
Sequential Images ◽  
Significant Superiority

Thirty-nine temporomandibular joints (TMJ) from 20 patients with suspected internal derangements were imaged by a 1.5 T MR imager. The on-resonance binomial magnetization transfer contrast (MTC) pulse was applied to gradient echo images with a dual receiver coil (9 s/section). With the use of an opening device, a series of sequential images were obtained at increments of mouth opening and closing. The tissue signal intensities with (Ms) and without (Mo) MTC were measured and subjective image analysis was performed. Compared with the standard images, MTC technique provided selective signal suppression of disks. The average of Ms/Mo ratio of the disks (0.56) was lower than that of the retrodiskal pad (0.79) and of the effusion (0.89). With MTC technique, fluid conspicuity was superior to standard image. However, no significant superiority was found in disk definition subjectively.

Exercise-Induced Changes in Magnetization Transfer Contrast of Muscles

1993 ◽  
Vol 34 (6) ◽  
pp. 559-562 ◽  
Author(s):  
K. T. Mattila ◽  
M. E. S. Komu ◽  
S. K. Koskinen ◽  
P. T. Niemi
Keyword(s):  
Signal Intensity ◽  
Magnetization Transfer ◽  
Intensity Increase ◽  
Gradient Echo ◽  
Magnetization Transfer Contrast ◽  
Flexor Muscles ◽  
Motion Exercise ◽  
New Type ◽  
Exercise Induced ◽  
Induced Changes

Magnetization transfer contrast (MTC) technique provides a new type of contrast in MR imaging. The MTC method is based on the interaction between the spins of free protons and those with restricted motion. Exercise-induced changes in signal intensity and MTC were measured in the forearm muscles of 10 volunteers at 0.1 T. There was 26% increase in signal intensity of active flexor muscles after exercise when imaged with ordinary gradient echo sequence. Despite this marked intensity increase, the postexercise values of MTC did not differ from the preexercise ones.

Magnetization Transfer Contrast on Gradient Echo MR Imaging of the Temporomandibular Joint

1995 ◽  
Vol 36 (3) ◽  
pp. 295-299 ◽  
Author(s):  
Mamoru Niitsu ◽  
H. Hirohata ◽  
H. Yoshioka ◽  
I. Anno ◽  
N. G. Campeau ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Temporomandibular Joint ◽  
Magnetization Transfer ◽  
Gradient Echo ◽  
Magnetization Transfer Contrast

scholarly journals A Clinical Jaw Movement Training Robot for Mouth Opening/Closing and Lateral Movement Training

2004 ◽  
Vol 16 (6) ◽  
pp. 579-586 ◽  
Author(s):  
Akihisa Okino ◽  
◽  
Hideaki Takanobu ◽  
Atsuo Takanishi ◽  
Kayoko Ohtsuki ◽  
...  
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Mouth Opening ◽  
Lateral Movement ◽  
Jaw Movement ◽  
Movement Training ◽  
Temporomandibular Joints ◽  
Jaw Opening ◽  
Opening And Closing ◽  
Mandibular Joints

This paper discusses a jaw movement training robot implementing a 6-DOF (degrees of freedom) parallel mechanism, and its application to mouth opening and closing and lateral movement training. Temporomandibular joints (TMJ) syndrome prevents patients from opening their mouths or moving their jaws easily due to problems with mandibular joints, mastication muscles, and other organs involved in food chewing. Conventional therapy involves simple mouth opening apparatuses, although individual techniques vary with the physician. We developed and improved a jaw movement training robot that aids jaw opening and closing and lateral jaw movement training. This system consists of a 6-DOF slave manipulator representing a patient manipulator and a 2-DOF or 3-DOF master manipulator representing the doctor command manipulator.

Magnetization transfer contrast of hepatic lesions in breath-hold gradient-echo images of different T1 weighting

1997 ◽  
Vol 7 (2) ◽  
pp. 280-285 ◽  
Author(s):  
Fritz Schick ◽  
Wolfgang Stern ◽  
Jürgen Forster ◽  
Michael Laniado ◽  
Otto Lutz ◽  
...  
Keyword(s):  
Magnetization Transfer ◽  
Breath Hold ◽  
Gradient Echo ◽  
Magnetization Transfer Contrast ◽  
Hepatic Lesions

scholarly journals CEST, ASL, and magnetization transfer contrast: How similar pulse sequences detect different phenomena

2018 ◽  
Vol 80 (4) ◽  
pp. 1320-1340 ◽  
Author(s):  
Linda Knutsson ◽  
Jiadi Xu ◽  
André Ahlgren ◽  
Peter C.M van Zijl
Keyword(s):  
Magnetization Transfer ◽  
Pulse Sequences ◽  
Magnetization Transfer Contrast

scholarly journals A New Tridimensional Insight into Geometric and Kinematic Characteristics of Masticatory Cycles in Participants with Normal Occlusion

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Ramón Fuentes ◽  
Alain Arias ◽  
María Florencia Lezcano ◽  
Diego Saravia ◽  
Gisaku Kuramochi ◽  
...  
Keyword(s):  
Mouth Opening ◽  
Mandibular Movement ◽  
Electromagnetic Articulography ◽  
Kinematic Characteristics ◽  
Normal Occlusion ◽  
Significant Difference ◽  
Number Of Cycles ◽  
Opening And Closing ◽  
Mandibular Movements ◽  
Insight Into

The aim of this study was to analyze the general, geometric, and kinematic characteristics of the masticatory cycle’s movements in a tridimensional way, using a method developed by our study group to provide a new insight into the analysis of mandibular movements due to advancement in the potential of computational analysis. Ten individuals (20.1 ± 2.69 years), molar class I, without mandibular movement problems participated in this study. The movements of the masticatory cycles, frontal and sagittal mandibular border movements, were recorded using 3D electromagnetic articulography and processed with computational scripts developed by our research group. The number of chewing cycles, frequency (cycles/s), chewing cycle areas/mandibular border movements areas ratios, and the mouth opening and closing speeds on the 3D trajectory of the chewing cycle were compared. The cycles were divided and analyzed in thirds. The masticatory cycles showed high variation among the individuals (21.6 ± 9.4 cycles); the frequency (1.46 ± 0.21 cycles/s) revealed a moderate positive correlation (R = 0.52) with the number of cycles. The frontal area ratios between the cycle area and the mandibular border movement presented higher values in the first third (6.65%) of the masticatory cycles, and the ratios of sagittal areas were higher and more variable (first, 7.67%; second, 8.06%; and third, 10.04%) than the frontal view. The opening and closing mouth speeds were greater in the second third of the masticatory cycles (OS, 57.82 mm/s; CS, 58.34 mm/s) without a significant difference between the opening and closing movements when the same thirds were evaluated. Further studies are necessary to improve the understanding of the masticatory cycles regarding the standardization of parameters and their values.

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