Transmission imaging is receiving increasing attention in SPECT due to the need to compensate for nonuniform attenuation in cardiac-chest SPECT. The quality of a transmission image has an important effect on the measured attenuation distribution. To improve image quality, knowledge of the performance characteristics of a transmission imaging system is essential. The characteristics, spatial resolution, detection efficiency, photon flux, and exposure to the object, of a transmission imaging system consisting of a gamma camera and a uniform sheet source have been studied. The results demonstrate that spatial resolution of a transmission imaging system can be improved by use of a high-resolution source collimator at the price of a moderate decrease in detection efficiency, in comparison to the uncollimated case. Also, the source collimator significantly reduces the photon flux and exposure to the object. This investigation suggests that a high-resolution collimator be used with an intense sheet source to improve spatial resolution and reduce statistical noise with low exposure to the patient. This research further suggests that the amount of source activity is determined by the requirement of image quality, detection geometry, and allowed absorbed dose to the patient.
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http://dx.doi.org/10.1118/1.596752 | DOI Listing |
J Transl Med
January 2025
Department of General Surgery (Colorectal Surgery), The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.
Accurate and fast histological diagnosis of cancers is crucial for successful treatment. The deep learning-based approaches have assisted pathologists in efficient cancer diagnosis. The remodeled microenvironment and field cancerization may enable the cancer-specific features in the image of non-cancer regions surrounding cancer, which may provide additional information not available in the cancer region to improve cancer diagnosis.
View Article and Find Full Text PDFBMC Pregnancy Childbirth
January 2025
Department of Infectious Diseases, Ganzhou Fifth People's Hospital, Ganzhou, China.
Background: Antiretroviral drugs are essential for preventing mother-to-child transmission (MTCT) of HIV in HIV-infected pregnant women. However, ART treatment for HIV-infected pregnant women with multidrug resistance remains a major challenge. Effective and safe ART regimens for preventing MTCT should be tailored to this special population.
View Article and Find Full Text PDFTrends Neurosci
January 2025
Hefei National Laboratory for Physical Sciences at the Microscale, Department of Neurology in the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; Anhui Province Key Laboratory of Biomedical Imaging and Intelligent Processing, Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China. Electronic address:
The precise organization of the complex set of synaptic proteins at the nanometer scale is crucial for synaptic transmission. At the heart of this nanoscale architecture lies the nanocolumn. This aligns presynaptic neurotransmitter release with a high local density of postsynaptic receptor channels, thereby optimizing synaptic strength.
View Article and Find Full Text PDFJ Vasc Interv Radiol
January 2025
Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS 66506, USA; Department of Biomedical Engineering, The George Washington University, Washington, DC 20052, USA. Electronic address:
Purpose: To determine the technical feasibility of discriminating discontiguous from contiguous ablation zones between a pair of microwave ablation (MWA) applicators using broadband microwave transmission signal measurements in an in vivo porcine liver model.
Methods: Dual applicator 2.45GHz MWA was performed using one directional and one omnidirectional applicator, spaced 3cm apart, under imaging guidance.
Eur J Obstet Gynecol Reprod Biol
January 2025
Objectives: To review the currently available Clinical Practice Guidelines regarding the diagnosis and management of Cytomegalovirus (CMV) infection in pregnancy.
Methods: Medline, Turning Research into Practice (TRIP), Web of Science databases and scientific societies' websites were searched electronically up to April 2024. We included national and international Clinical Practice Guidelines regarding diagnosis, treatment and follow-up of CMV infection in pregnancy, published in English language.
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