Volume imaging positron emission tomographic (PET) scanners with no septa and a large axial acceptance angle offer several advantages over multiring PET scanners. A volume imaging scanner combines high sensitivity with fine axial sampling and spatial resolution. The fine axial sampling minimizes the partial volume effect, which affects the measured concentration of an object. Even if the size of an object is large compared to the slice spacing in a multiring scanner, significant variation in the concentration is measured as a function of the axial position of the object. With a volume imaging scanner, it is necessary to use a three-dimensional reconstruction algorithm in order to avoid variations in the axial resolution as a function of the distance from the center of the scanner. In addition, good energy resolution is needed in order to use a high energy threshold to reduce the coincident scattered radiation.
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http://dx.doi.org/10.1038/jcbfm.1991.35 | DOI Listing |
Neurology
February 2025
Division of Clinical and Metabolic Genetics, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Ontario, Canada.
Pathogenic variants in cause congenital muscular dystrophy through hypoglycosylation of alpha-dystroglycan (OMIM #615350). The established phenotypic spectrum of GMPPB-related disorders includes recurrent rhabdomyolysis, limb-girdle muscular dystrophy, neuromuscular transmission abnormalities, and congenital muscular dystrophy with variable brain and eye anomalies. We report a 9-month-old male infant with congenital muscular dystrophy, infantile spasms, and compound heterozygous pathogenic variants (c.
View Article and Find Full Text PDFAJR Am J Roentgenol
January 2025
Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene Street, Baltimore, MD 21201.
Academic radiology practices are navigating unprecedented operational and financial challenges, including a growing radiologist shortage, escalating imaging volumes, and mounting financial pressures driven by rising salaries, increasing practice expenses, and declining reimbursements. To address these challenges, academic department leaders must prioritize securing enhanced hospital professional service agreements and renegotiating outpatient imaging agreements. These strategic initiatives are essential to sustaining academic missions and ensuring long-term success.
View Article and Find Full Text PDFBrain
January 2025
U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), Neuropresage Team; INSERM, University of Caen Normandy; GIP Cyceron, 14000 Caen, France.
Curing Alzheimer's disease remains hampered by an incomplete understanding of its pathophysiology and progression. Exploring dysfunction in medial temporal lobe networks, particularly the anterior-temporal (AT) and posterior-medial (PM) systems, may provide key insights, as these networks exhibit functional connectivity alterations along the entire Alzheimer's continuum, potentially influencing disease propagation. However, the specific changes in each network and their clinical relevance across stages are not yet fully understood.
View Article and Find Full Text PDFTransl Vis Sci Technol
January 2025
New England Eye Center, Tufts Medical Center, Boston, MA, USA.
Purpose: To evaluate visibility of a sub-band posterior to the external limiting membrane (ELM) and assess its age-associated variation.
Methods: In a retrospective cross-sectional study, normal eyes were imaged using a high-resolution spectral-domain optical coherence tomography (SD-OCT) prototype (2.7-µm axial resolution).
Int Urol Nephrol
January 2025
Department of Intensive Care Unit, School of Medicine, Tianjin First Central Hospital, Nankai University, Tianjin, People's Republic of China.
Background: Acute kidney injury (AKI) is a significant clinical condition, and ultrasound examination has emerged as a crucial non-invasive imaging method for assessing kidney status, especially in its diagnosis and management. This study aims to perform a bibliometric analysis to clarify current research trends in ultrasound assessment of AKI.
Methods: We conducted a literature search in the Web of Science database using keywords related to ultrasound examinations of acute kidney injury, up to November 15, 2023.
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