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Age-related deterioration in positron emission tomography (PET) systems can be monitored using cross-calibration scans for scanner calibration. This study aimed to evaluate changes in the sensitivity of a PET system over time using routinely collected cross-calibration factor (CCF) measurement data and NEMA sensitivity measurement data acquired at our facility. We used CCF measurement data acquired over eight years, from 2016 to 2023. The count rates were calculated from raw data. The NEMA sensitivity measurements were also performed in 2017 and 2024 to compare with the sensitivities obtained from the CCF measurements. The PET images were reconstructed using the CCF data. A region of interest (ROI) was placed at the center of the PET images and count rates from the PET images were obtained. The sensitivity changes in the CCF data showed a linear decrease in sensitivity over eight years, with a mean annual reduction rate of approximately 2.0%. A comparison of the NEMA sensitivity measurements indicated a decrease in sensitivity, with a 12% reduction over eight eight years. The sensitivity was higher at the center of the axial field of view than at the edges. The ROI data also showed a linear decrease in sensitivity. This is consistent with the CCF data. Additionally, the coefficient of variation increased towards the edge of the slice. By utilizing the CCF measurement data, we obtained age-related changes in the PET system, suggesting that the PET system used in our facility may experience an annual sensitivity deterioration of approximately 2.0%.
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http://dx.doi.org/10.1007/s12194-025-00882-6 | DOI Listing |
BMC Psychol
September 2025
Behavioral Epidemiology, Institute of Clinical Psychology and Psychotherapy, TUD Dresden University of Technology, Chemnitzer Straße 46, 01187, Dresden, Germany.
Background: Disruptive behavior and emotional problems - especially anxiety - are common in children and frequently co-occur. However, the role of co-occurring emotional problems in disruptive behavior intervention response is unclear. This study aimed to compare the effectiveness of an indicated prevention program in children with disruptive behavior problems with vs.
View Article and Find Full Text PDFFluids Barriers CNS
September 2025
Department of Medical Sciences, Neurology, Uppsala University, Uppsala, Sweden.
Background: Idiopathic normal pressure hydrocephalus (iNPH) predominantly manifests with gait disturbances, yet clinical assessments are vulnerable to confirmation bias, particularly post-shunt surgery. Blinded video evaluations are a method to enhance objectivity in gait assessment, but their reliability has never been systematically investigated. The aim was to evaluate the inter-rater reliability of blinded gait assessments in iNPH patients and to investigate how these assessments correlate with the Hellström iNPH scale and patient-reported health status following shunt surgery.
View Article and Find Full Text PDFBMC Health Serv Res
September 2025
Institute of General Practice, Rostock University Medical Center, Doberaner Str. 142, Rostock, 18057, Germany.
Background: Post-viral syndromes, including long- and post-COVID, often lead to persistent symptoms such as fatigue and dyspnoea, affecting patients' daily lives and ability to work. The COVI-Care M-V trial examines whether interprofessional, patient-centred teleconsultations, initiated by general practitioners in cooperation with specialists, can help reduce symptom burden and improve care for patients.
Methods: To evaluate the effectiveness of the intervention under routine care conditions, a cluster-randomised controlled trial is being conducted.
Ren Fail
December 2025
Department of Nephrology, Kidney Disease Medical Center, Tianjin Medical University General Hospital, National Key Clinical Specialty, Tianjin Key Medical Discipline, Tianjin, China.
Purpose: This study aimed to investigate the association between body roundness index (BRI) and deaths from all causes and cardiovascular disease (CVD) in participants with chronic kidney disease (CKD).
Materials And Methods: The data was sourced from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Cox proportional hazards regression along with restricted cubic splines were applied to assess the associations of BRI with deaths from all causes and CVD in individuals with CKD.
BMC Public Health
September 2025
Division of Insurance Medicine, Department of Clinical Neuroscience, Karolinska Institutet, 171 77, Stockholm, Sweden.
Background: As populations age, more knowledge is needed on people who extend their working lives. The aim of this study was to explore if prior sickness absence (> 14 days) and/or disability pension (SADP) in mental and/or somatic diagnoses were associated with time until work exit after ages 65-69 and ≥ 70, respectively, among women and men.
Methods: This prospective population-based cohort study included all 65-69-year-olds (cohort65, n = 201,263) and ≥ 70-year-olds (cohort70, n = 93,751) who were in paid work in Sweden in 2014.