Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , COVID-19 , Encefalitis Antirreceptor N-Metil-D-Aspartato/complicaciones , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico por imagen , COVID-19/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Tomografía de Emisión de Positrones/métodos , SARS-CoV-2Asunto(s)
Enfermedad de Castleman , Linfoma de Células B Grandes Difuso , Enfermedad de Castleman/diagnóstico por imagen , Células Dendríticas Foliculares/patología , Fluorodesoxiglucosa F18 , Estudios de Seguimiento , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/patología , Tomografía Computarizada por Tomografía de Emisión de PositronesRESUMEN
Gated-SPECT myocardial perfusion imaging is a widely used technique indicated for assessment of patients with no clear diagnosis of ischemic heart disease. Early rest gated-SPECT myocardial perfusion study in patients with acute chest pain has high sensitivity and high negative predictive value for ruling out coronary disease. We report a case of a patient admitted for the study of her chest pain. She underwent a myocardial perfusion stress-rest whose interpretation could have been equivocal due to the clinical status of the patient during the injection of the radiotracer.
Asunto(s)
Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca/métodos , Dolor en el Pecho/diagnóstico por imagen , Isquemia Miocárdica/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Anciano , Cateterismo Cardíaco , Diabetes Mellitus Tipo 2/complicaciones , Electrocardiografía , Prueba de Esfuerzo , Reacciones Falso Negativas , Femenino , Humanos , Hipertrigliceridemia/complicaciones , Radiofármacos , Tecnecio Tc 99m SestamibiAsunto(s)
Anomalías Múltiples/diagnóstico por imagen , Albúminas/farmacocinética , Aorta/diagnóstico por imagen , Fístula Arterio-Arterial/diagnóstico por imagen , Pulmón/irrigación sanguínea , Angiografía por Resonancia Magnética , Radiofármacos/farmacocinética , Tetralogía de Fallot/cirugía , Relación Ventilacion-Perfusión , Adolescente , Aorta/anomalías , Fístula Arterio-Arterial/congénito , Circulación Colateral , Humanos , Masculino , CintigrafíaRESUMEN
OBJECTIVE: To study the influence of the 18F-FDG radioactive concentration and the usual greatest storage time of the radiopharmaceutical at the Radiopharmacy Unit (RU) over its radiochemical purity. MATERIAL AND METHODS: Thirty 18F-FDG preparations coming from different batches were studied. The radiochemical purity was determined at the RU by means of TLC to saline-diluted (1:10) and undiluted samples of each preparation, in the early 30 minutes since its arrival and 5 hours later. The radiochemical purity of the original 18F-FDG was determined at the PET radiopharmaceutical producer Laboratory (PETL) by means of HPLC in the early hour since the 18F-FDG dispensing. RESULTS: The increase of 18F-Fluoride found in the (5 h-30 min) period was significantly greater in the samples without diluting than in the diluted ones (p < 0.0001). We found a significant correlation between the percent of this increase of 18F-Fluoride (y) and the radioactive concentration of the 18F-FDG (x): y = 0.00061x + 0.1759 (R2 = 0.198; p < 0.0005). The percent of 18F-Fluoride determined at the RU was significantly higher than the percent of 18F-Fluoride determined at the PETL (p < 0.0001). A significant correlation between the differences of the percent of 18F-Fluoride determined by TLC and HPLC (y) and the radioactive concentration (x) was found: y = 0.0139x + 0.3146 (R2 = 0.196; p = 0.016). A significant correlation among the differences of percent 18F-Fluoride determined by TLC and HPLC ([%F] RU - [%F] PETL), the radioactive concentration (RC) and the time since the radiopharmaceutical dispensing (t) was found: [%F] RU - [%F] PETL = 0.01159*RC (mCi/mL) + 0.250*t (h) - 0.01903 (R2 = 0.226; p < 0.014). CONCLUSIONS: The stability of the 18F-FDG preparations with time increases when diminishing its concentration. We recommended the dilution of these preparations with physiological saline solution.
