Purpose: Marked changes in left ventricular diastolic filling occur with advancing age, but alterations in myocardial movement accompanying these findings have not been previously documented. We aimed to identify differences in myocardial motion during relaxation and diastole using magnetic resonance imaging (MRI), with tagging, which uniquely allows accurate, noninvasive assessment of myocardial movement in three dimensions.
Methods: Tagged MRI images from two groups of normal individuals were analyzed using dedicated computer software to provide values for group comparison of apical rotation, torsion, and circumferential and longitudinal strain throughout the cardiac cycle.
Results: The mean age of the younger group was 22 years, (n = 15) and that of the older group was 69 years, (n = 16). In the older group, peak apical rotation and torsion were increased during systole and significantly more apical rotation, torsion, circumferential, and longitudinal strain persisted during myocardial relaxation and diastole. In addition, peak normalized reversal of apical rotation was reduced (-5.1 +/- 1.2 degrees s-1 vs. -6.7 +/- 1.2 degrees s-1, p = 0.001), and there were slower peak rates of circumferential lengthening (76.2 +/- 28% s-1 vs. 142.5 +/- 17% s-1, p < 0.001) and longitudinal lengthening (62.7 +/- 21% s-1 vs. 122.5 +/- 20% s-1, p < 0.001).
Conclusions: Tagged MRI is a unique, noninvasive imaging method that can identify significant prolongation and reduction of myocardial relaxation in older compared with young normal individuals.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1081/jcmr-120022258 | DOI Listing |
Asian Spine J
December 2024
Department of Spine Surgery, Bombay Hospital and Medical Research Centre, Mumbai, India.
Study Design: A retrospective comparative study.
Purpose: To validate the hypothesis that a combination of multilevel Ponte osteotomy (PO) with intraoperative traction (IOT) results in a better correction than IOT alone in high-magnitude curves in adolescent idiopathic scoliosis (AIS) and does not possess an attributable risk of neurological injury.
Overview Of Literature: On a comprehensive review of the literature, the choice of technique adopted for curves between 65° and 100° remains controversial with no major consensus favoring one technique over the other.
J Clin Neurosci
December 2024
Institute of Mechanical Engineering, Dalian Jiaotong University, Dalian 116028, Liaoning, China.
(1) Background: External force orthopedics and the strengthening of paraspinal muscles through exercise are common orthopedic methods for adolescent scoliosis, yet the synergetic mechanism of the two in orthopedic correction remains unclear. (2) Methods: A three-dimensional finite element model of the scoliotic spine was established to accurately simulate the mechanical properties of tissues such as the spine, intervertebral discs, and ribs. By applying external forces in different directions to the scoliosis model, the orthopedic effects of these forces on scoliosis were analyzed.
View Article and Find Full Text PDFDent J (Basel)
November 2024
Department of General Surgery and Surgical-Medical Specialties, University of Catania, 95131 Catania, Italy.
: Apical extrusion of debris can affect the success of endodontic treatments, and the specific performance of certain retreatment systems has not been studied yet. Therefore, the aim of this in vitro study was to quantitatively assess the amount of apically extruded debris produced during retreatment procedures using three rotary NiTi retreatment systems in mature non-resorbed straight roots. : Thirty extracted permanent human teeth with single straight roots were selected.
View Article and Find Full Text PDFJ Clin Med
November 2024
Department of Medicine, Albert Szent-Györgyi Medical School, University of Szeged, H-6725 Szeged, Hungary.
While the basal region of the left ventricle (LV) rotates in a clockwise (cw) direction, the apical regions of the LV rotate in a counterclockwise (ccw) direction in healthy circumstances. Although LV rotational mechanics help optimize LV ejection, in some cases, LV twist is missing. This clinical situation, when the LV base and the apex rotate in the same cw or ccw direction, is called LV 'rigid body rotation' (LV-RBR).
View Article and Find Full Text PDFDiagnostics (Basel)
December 2024
Department of Dentomaxillofacial Radiology, Ataturk University, 25240 Erzurum, Türkiye.
The growing demand for artificial intelligence (AI) in healthcare is driven by the need for more robust and automated diagnostic systems. These methods not only provide accurate diagnoses but also promise to enhance operational efficiency and optimize resource utilization in clinical workflows. In the field of dental lesion detection, the application of deep learning models to various imaging techniques has gained significant prominence.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!