scholarly journals Identifying Predictors of Levator Veli Palatini Muscle Contraction During Speech Using Dynamic Magnetic Resonance Imaging

2020 ◽  
Vol 63 (6) ◽  
pp. 1726-1735
Author(s):  
Eshan Pua Schleif ◽  
Catherine M. Pelland ◽  
Charles Ellis ◽  
Xiangming Fang ◽  
Stephen J. Leierer ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Three Dimensional ◽  
Magnetic Resonance Images ◽  
Normal Anatomy ◽  
Imaging Protocol ◽  
Contraction Velocity ◽  
Levator Veli Palatini ◽  
Dynamic Magnetic Resonance ◽  
Velopharyngeal Closure ◽  
Modeling Software

Purpose The purpose of this study was to identify predictors of levator veli palatini (LVP) muscle shortening and maximum contraction velocity in adults with normal anatomy. Method Twenty-two Caucasian English-speaking adults with normal speech and resonance were recruited. Participants included 11 men and 11 women ( M = 22.8 years, SD = 4.1) with normal anatomy. Static magnetic resonance images were obtained using a three-dimensional static imaging protocol. Midsagittal and oblique coronal planes were established for visualization of the velum and LVP muscle at rest. Dynamic magnetic resonance images were obtained in the oblique coronal plane during production of “ansa.” Amira 6.0.1 Visualization and Volume Modeling Software and MATLAB were used to analyze images and calculate LVP shortening and maximum contraction velocity. Results Significant predictors ( p < .05) of maximum LVP shortening during velopharyngeal closure included mean extravelar length, LVP origin-to-origin distance, velar thickness, pharyngeal depth, and velopharyngeal ratio. Significant predictors ( p < .05) of maximum contraction velocity during velopharyngeal closure included mean extravelar length, intravelar length, LVP origin-to-origin distance, and velar thickness. Conclusions This study identified six velopharyngeal variables that predict LVP muscle function during real-time speech. These predictors should be considered among children and individuals with repaired cleft palate in future studies.

The Safety of Operating on Breasts With a History of Prior Reduction Mammoplasty: Dynamic Magnetic Resonance Imaging Analysis of Angiogenesis

2021 ◽  
Author(s):  
Joseph Kyu-hyung Park ◽  
Seokwon Park ◽  
Chan Yeong Heo ◽  
Jae Hoon Jeong ◽  
Bola Yun ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Three Dimensional ◽  
Venous Drainage ◽  
Reduction Mammoplasty ◽  
Magnetic Resonance Images ◽  
Areolar Complex ◽  
Internal Mammary ◽  
Initial Procedure ◽  
Nipple Sparing Mastectomy ◽  
Nipple Sparing

Abstract Background Vascularity of the nipple-areolar complex (NAC) is altered after reduction mammoplasty, which increases complications risks after repeat reduction or nipple-sparing mastectomy. Objectives To evaluate angiogenesis of the NAC via serial analysis of breast magnetic resonance images (MRIs). Methods Breast MRIs after reduction mammoplasty were analyzed for 35 patients (39 breasts) using three-dimensional reconstructions of maximal intensity projection images. All veins terminating at the NAC were classified as internal mammary, anterior intercostal, or lateral thoracic in origin. The vein with the largest diameter was considered the dominant vein. Images were classified based on the time since reduction: &lt;6 months, 6-12 months, 12-24 months, &gt;2 years. Results The average number of veins increased over time: 1.17 (&lt;6 months), 1.56 (6–12 months), 1.64 (12–24 months), 1.73 (&gt;2 years). Within 6 months, the pedicle was the only vein. Veins from other sources began to appear at 6–12 months. In most patients, at least two veins were available after 1 year. After 1 year, the internal mammary vein was the most common dominant vein regardless of the pedicle used. Conclusions In the initial 6 months after reduction mammoplasty, the pedicle is the only source of venous drainage; however, additional sources are available after 1 year. The internal thoracic vein was the dominant in most patients. Thus, repeat reduction mammoplasty or nipple-sparing mastectomy should be performed ≥1 year following the initial procedure. After 1 year, the superior or superomedial pedicle may represent the safest option when the previous pedicle is unknown.

scholarly journals Added value of dynamic magnetic resonance images in pelvic floor dysfunction

2020 ◽  
Vol 40 (2) ◽  
pp. 163-167
Author(s):  
Guillermo O. Rosato ◽  
Carina Chwat ◽  
Gustavo Lemme ◽  
Flavia Alexandre ◽  
Diego Valli ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Pelvic Floor ◽  
Pelvic Floor Dysfunction ◽  
Magnetic Resonance Images ◽  
Added Value ◽  
Dynamic Magnetic Resonance

scholarly journals ECG-gated dynamic magnetic resonance imaging method for examination of the pig heart

2001 ◽  
Vol 49 (3) ◽  
pp. 275-284
Author(s):  
Zs. Petrási ◽  
R. Romvári ◽  
G. Bajzik ◽  
B. Fenyves ◽  
I. Repa ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Three Dimensional ◽  
Dynamic Magnetic Resonance Imaging ◽  
Imaging Method ◽  
Resonance Imaging ◽  
Dynamic Magnetic Resonance ◽  
Heart Cycle ◽  
The Right

A dynamic magnetic resonance imaging (MRI) method was developed for in vivo examination of the pig heart. Measurements were carried out on 15 meat-type pigs of different liveweight using a 1.5 T equipment. Inhalation anaesthesia was applied, then data acquisition was synchronised by ECG gating. Depending on the heart rate and heart size, in each case 8 to 10 slices and in each slice 8 to 14 phases were acquired prospectively according to one heart cycle. During the post-processing of the images the left and the right ventricular volumes were determined. The values measured at 106 kg liveweight are 2.5 times higher than those obtained at 22 kg, while the ejection fractions are equal. The calculated cardiac output values were 3.5 l (22 kg, 132 beats/min.), and 6.0 l (106 kg, 91 beats/min.), respectively. After measuring the wall thickness, the contraction values were also determined for the septum (70%), and for the anterior (61%), posterior (41%) and lateral (54%) walls of the left ventricle. Three-dimensional animated models of the ventricles were constructed. Based on the investigations performed, the preconditioning, the anaesthetic procedure, the specific details of ECG measurement and the correct MR imaging technique were worked out.

Comparing two approaches to rigid registration of three-dimensional ultrasound and magnetic resonance images for neurosurgery

2011 ◽  
Vol 7 (1) ◽  
pp. 125-136 ◽  
Author(s):  
Laurence Mercier ◽  
Vladimir Fonov ◽  
Claire Haegelen ◽  
Rolando F. Del Maestro ◽  
Kevin Petrecca ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Three Dimensional ◽  
Magnetic Resonance Images ◽  
Rigid Registration
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