The nuclear magnetic resonance (NMR) surface scanner, which provides images of sample surfaces larger than the probe dimension, has been realized using a single-sided device. Although conditioned by distortion effects originated by convolution between the sensitive volume of the probe and the space structures to be imaged, the scanner is able to provide images with good spatial resolution. The images obtained by the surface scanner can be made sensitive to relaxation parameters, magnetization or molecular self-diffusion; also, the dimension perpendicular to the sample surface can be scanned by varying the depth from which the probe detects the sample signal. It may scan surfaces arbitrarily large and with some degree of curvature. This aspect, together with the noninvasive characteristic of the apparatus, indicates that the surface scanner could be used profitably in the field of cultural heritage, where it could provide NMR maps of frescos, paintings on wood, marble artifacts, books and others.
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http://dx.doi.org/10.1016/j.mri.2006.03.005 | DOI Listing |
J Dent Sci
January 2025
Department of Dentistry, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
Background/purpose: Different types of scanners are gradually used to produce digital dental casts in the current dental practice. This study tested the accuracy of the three desktop scanners and two intraoral scanners and evaluated whether the desktop scanners had higher precision than the intraoral scanners.
Materials And Methods: This study used the three desktop and two intraoral scanners to scan a standard dental cast 5 times.
Magn Reson Med
January 2025
MRI Research Centre, Physics, University of New Brunswick, Fredericton, New Brunswick, Canada.
Purpose: Magnetic resonance elastography (MRE) provides detailed maps of tissue stiffness, helping to diagnose various health conditions, but requires the use of expensive clinical MRI scanners. Our approach utilizes compact, cost-effective portable MR sensors that offer bulk characterization of material properties in a region of interest close to the surface (within 1-2 cm). This accessible instrument could enable routine monitoring and prevention of diseases not readily evaluated with conventional tools.
View Article and Find Full Text PDFInt J Clin Pediatr Dent
December 2024
Department of Pediatric Dentistry, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia.
Aims And Background: This study aimed to assess the accuracy of digital intraoral scans in capturing the three-dimensional (3D) surface of teeth and dental arches in mixed dentition, compared with conventional plaster models. Intraoral scanning technology has seen rapid advancements in recent years, revolutionizing orthodontic and dental practices. However, its accuracy in mixed dentition remains a subject of investigation.
View Article and Find Full Text PDFMed Phys
January 2025
Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
Background: The spatial resolution of new, photon counting detector (PCD) CT scanners is limited by the size of the focal spot. Smaller, brighter focal spots would melt the tungsten focal track of a conventional X-ray source.
Purpose: To propose focal spot multiplexing (FSM), an architecture to improve the power of small focal spots and thereby enable higher resolution clinical PCD CT.
Micromachines (Basel)
January 2025
Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
This paper presents, for the first time, a rotary actuator functionalized by an inclined disc rotor that serves as a distal optical scanner for endoscopic probes, enabling side-viewing endoscopy in luminal organs using different imaging/analytic modalities such as optical coherence tomography and Raman spectroscopy. This scanner uses a magnetic rotor designed to have a mirror surface on its backside, being electromagnetically driven to roll around the cone-shaped hollow base to create a motion just like a precessing coin. An optical probing beam directed from the probe's optic fiber is passed through the hollow cone to be incident and bent on the back mirror of the rotating inclined rotor, circulating the probing beam around the scanner for full 360° sideway imaging.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!