MRI is increasingly being used as an interventional tool in neurosurgery. The field strength of "intraoperative" MR systems is usually lower than that of imagers commonly used for diagnostic purposes. However, lesion enhancement and apparent lesion extent depend on field strength. The aim of this study was to compare the contrast between intracranial, contrast-enhancing space-occupying lesions and the surrounding white matter obtained with low-field (0.2 T) and high-field (1.5 T) MR imaging and to find the contrast medium dosage for low-field MRI that produces the same lesion-to-white-matter contrast as the one obtained with high-field MRI after the administration of a standard dose of the contrast medium. A total of 38 patients with intracranial metastases or high-grade glioma were enrolled in this study. T1-weighted spin-echo sequences were acquired. High-field (1.5 T) studies were performed after the i.v. administration of 0.1 mmol gadolinium-DTPA/kg body weight. For low-field MRI (0.2 T) a dose escalation technique was used. T1-weighted sequences were repeated after each of three i. v. injections of 0.1 mmol gadolinium-DTPA/kg body weight. Thus, at the low-field examinations three T1-weighted sequences with a contrast medium dosage of 0.1, 0.2 and 0.3 mmol gadolinium-DTPA/kg body weight were obtained. Lesion-to-white-matter contrasts were calculated and compared. The average lesion-to-white-matter contrast obtained with high-field MR examinations was 1.63 (standard deviation 0.32). In the low-field MR examinations the average lesion-to-white-matter contrast was 1.34 (0.2) after a single dose, 1.57 (0.2) after a double dose, and 1.71 (.19) after a triple dose of contrast medium. The lesion-to-white-matter contrast of the high-field MR examination after a single dose of contrast medium was significantly higher than that of the low-field study after a single dose (P < 0.0001), but did not differ significantly from the low-field studies after a double (P = 0.28) or a triple dose (P = 0.17) of contrast medium. In a series of patients with contrast-enhancing space occupying brain lesions low-field MRI (0.2 T) after a double dose of contrast medium yielded the same lesion-to-white-matter contrasts as high-field MRI (1.5 T) after a standard dose. This is an important finding to avoid errors in intraoperative MRI due to the immanently lower degree of lesion enhancement in low-field MR imaging.
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Radiographics
February 2025
From the Department of Radiology, Division of Abdominal Imaging, Mayo Clinic, 200 1st Street SW, Rochester, MN 55905 (K.C.H., M.L.W., C.L.W., J.F., S.K.V.); Department of Medical Imaging, University of Ottawa, Ottawa, Ontario, Canada (K.C.H.); Department of Medical Imaging, Beaujon University Hospital, Clichy, France (M.R.); HT Medica, Madrid, Spain (A.L.); Department of Radiology, University of Vienna, Vienna, Austria (A.B.S.); Department of Radiology, Sun Yat Sen University, Guangzhou, China (J.W.); and Department of Radiology, Division of Abdominal Imaging, Mayo Clinic, Scottsdale, Ariz (A.C.S.).
Hepatobiliary (HB) contrast agents are increasingly valuable diagnostic tools in MRI, offering a wider range of applications as their clinical use expands. Normal hepatocytes take up HB contrast agents, which are subsequently excreted in bile. This property creates a distinct HB phase providing valuable insights into liver function and biliary anatomy.
View Article and Find Full Text PDFInt Ophthalmol
January 2025
Department of Ophthalmology, Central Theater General Hospital, 627 Wuluo Road, Wuhan, 430070, China.
Purpose: The purpose is to evaluate the effect of drainage from intentional extramacular holes after internal limiting membrane insertion to treat macular hole retinal detachment (MHRD) in highly myopic eyes.
Methods: This study is a retrospective, observational, and comparative case series that included 25 consecutive highly myopic eyes with MHRD. All eyes underwent standard 23-gauge vitrectomy, inverted internal limiting membrane insertion into the macular hole, subretinal fluid drainage from an intentionally created extramacular retinal hole, and tamponade with either silicone oil (SO group, n = 13) or perfluoropropane (CF group, n = 12).
Biochim Biophys Acta Mol Cell Res
January 2025
Key Laboratory of Laboratory Medicine, Ministry of Education, Wenzhou Key Laboratory of Cancer Pathogenesis and Translation, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China. Electronic address:
The imbalance of microglial homeostasis is highly associated with age-related neurological diseases, where cytosolic endogenous DNA is also likely to be found. As the main medium for storing biological information, endogenous DNA could be localized to cellular compartments normally free of DNA when cells are stimulated. However, the intracellular trafficking of endogenous DNA remains unidentified.
View Article and Find Full Text PDFJ Virol Methods
January 2025
Department of Pharmacology, Physiology, and Biophysics, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA; National Emerging Infectious Diseases Laboratories, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA; Department of Virology, Immunology & Microbiology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA.
Direct SARS-CoV-2 infection of endothelial cells is challenging to study in vitro. To examine whether endothelial cell culture conditions impact the ability of SARS-CoV-2 to infect cells, we evaluated the effects of commercial cell culture media composition on SARS-CoV-2 Spike-directed viral infection. In African Green Monkey kidney epithelial cells (VeroE6), we found that commercial cell culture media (EGM2) produced inhibitory effects on recombinant vesicular stomatitis virus (rVSV-SARS-CoV-2) growth that is not seen in Dulbecco's Modified Eagle Medium (DMEM).
View Article and Find Full Text PDFJ Vis Exp
January 2025
State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University;
Cough is one of the most common symptoms of many respiratory diseases. Chronic cough significantly impacts quality of life and imposes a considerable economic burden. Increased cough sensitivity is a pathophysiological hallmark of chronic cough.
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