Background: It is essential that we find ways to reduce radiation exposure to children and maintain image quality.
Objectives: We compared radiation dose, image quality, and spatial resolution when continuous and pulse fluoroscopy with a full and half dose are applied to a phantom. The film-screen technique was compared to fluoroscopy with the digitized spot technique (fluoro grab image) in procedures such as voiding cystourethrogram (VCUG).
Materials And Methods: Using a 15.1-cm Plexiglas phantom, we obtained dosimetry in milligrays (mGy), spatial resolution in number of line pairs per millimeter (lp/mm), and threshold contrast resolution in number of visible holes. To measure total radiation dose, we calculated the average elapsed fluoroscopy time for VCUG to be approximately 3 min and estimated the average number of exposures as 10. Dosimetry was obtained for full dose and half dose continuous, for 15 pulses per second (pps), 7.5 pps, and 3.75 pps. These were also calculated with normal, magnification 1, and magnification 2 factors.
Results: Results of the two most relevant parameters are shown: continuous full-dose fluoroscopy, 3 min, 10 photo spots, total dose of 28.7 mGy with 2 lp/mm of resolution and a threshold contrast of 2.2%, versus 3.75 pps half-dose fluoroscopy, 3 min, grab images, total dose of 3.7 mGy with 1.9 lp/mm of resolution and a threshold contrast of 2.3%.
Conclusion: With minimal loss of resolution there is significant dose reduction (87%) when using 3.75 pps with digitized imaging.
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http://dx.doi.org/10.1007/s00247-002-0696-5 | DOI Listing |
Se Pu
January 2025
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
17-Estradiol (E2) is a natural steroidal estrogen essential for a variety of physiological functions in organisms. However, external E2, which is renowned for its potent biological effects, is also considered to be an endocrine-disrupting compound (EDC) capable of disturbing the normal operation of the endocrine system, even at nanogram-per-liter (ng/L) concentrations. Studies have revealed that medical and livestock wastewater can be contaminated with E2, which poses potential risks to human health.
View Article and Find Full Text PDFJ Clin Anesth
December 2024
Department of Anesthesiology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; Outcomes Research Consortium®, Houston, TX, USA. Electronic address:
Backgrounds: The cerebral oximetry index (CO) uses near-infrared spectroscopy to estimate cerebral autoregulation during cardiac surgery. However, the relationship between intraoperative loss of cerebral autoregulation and postoperative delirium or stroke remains unclear in patients recovering from carotid endarterectomy (CEA).
Methods: Our prospective observational cohort study enrolled patients scheduled for CEA.
J Acoust Soc Am
December 2024
Division of Humanities, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
In perceptual studies, musicality and pitch aptitude have been implicated in tone learning, while vocabulary size has been implicated in distributional (segment) learning. Moreover, working memory plays a role in the overnight consolidation of explicit-declarative L2 learning. This study examines how these factors uniquely account for individual differences in the distributional learning and consolidation of an L2 tone contrast, where learners are tonal language speakers, and the training is implicit.
View Article and Find Full Text PDFObjective: Aim: To evaluate and compare the functional outcomes and quality of life in distal rectal cancer patients after low anterior resection with the formation of a transverse double-fold reservoir (TDFR) and without it.
Patients And Methods: Materials and Methods: The retrospective study enrolled 80 patients with distal rectal cancer: 40 patients who underwent low anterior resection with the formation of a TDFR, and 40 patients with the formation of a colorectal anastomosis (control group). The follow-up period was 10-60 months, with a median follow-up of 36 months after primary surgery.
J Manag Care Spec Pharm
December 2024
Health Economics and Value Assessment, Sanofi, Boston, MA.
Background: Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening thrombotic microangiopathy. Caplacizumab is the only treatment approved by the European Medicines Agency and the US Food and Drug Administration for iTTP, to be given in combination with plasma exchange therapy (PEX) and immunosuppression (IS). The National Institute for Health and Care Excellence's independent appraisal committee assessed the cost-effectiveness of caplacizumab and concluded that the addition of caplacizumab to PEX+IS is cost-effective under a patient access scheme in the United Kingdom.
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