Una imagen PET amiloide estática del primer minuto (FMF) se correlaciona con [18F]FDG PET en pacientes con afasia progresiva primaria / Static first-minute-frame (FMF) PET imaging after 18F-labeled amyloid tracer injection is correlated to [18F]FDG PET in patients with primary progressive aphasia

Objetivo Estudiar la correlación entre una imagen PET estática del primer minuto (FMF) adquirida con radiotrazadores de amiloide marcados con flúor-18 y la PET cerebral con [18F]FDG en pacientes con afasia primaria progresiva (APP). Material y métodos La cohorte de estudio incluyó a 17 pacientes diagnosticados de APP con la siguiente distribución: 9APP variante no fluente, 4APP variante logopénica, 1APP variante semántica, 3APP inclasificables. Se extrajeron los SUVR regionales de las FMF y sus correspondientes imágenes PET con [18F]FDG y se calcularon los coeficientes de correlación de Pearson. Resultados Los SUVR de ambas imágenes mostraron patrones similares de alteración cerebral regional. Los análisis de correlación intrapaciente dieron como resultado un coeficiente medio de r=0,94 ±0,06. Los coeficientes de correlación regional entre pacientes de la cohorte del estudio fueron superiores a 0,81. Las subcohortes específicas según el radiotrazador y la variante de APP no mostraron diferencias en la similitud de las imágenes. Conclusiones La FMF estática podría ser una alternativa válida a la PET dinámica de amiloide en fase inicial propuesta en la literatura, así como un biomarcador de neurodegeneración para el diagnóstico y la clasificación de la APP en los estudios de PET amiloide (AU)

Objective To study the correlation between a static PET image of the first-minute-frame (FMF) acquired with 18F-labeled amyloid-binding radiotracers and brain [18F]FDG PET in patients with primary progressive aphasia (PPA). Material and methods The study cohort includes 17 patients diagnosed with PPA with the following distribution: 9nonfluent variant PPA, 4logopenic variant PPA, 1semantic variant PPA, 3unclassifiable PPA. Regional SUVRs are extracted from FMFs and their corresponding [18F]FDG PET images and Pearson's correlation coefficients are calculated. Results SUVRs of both images show similar patterns of regional cerebral alterations. Intrapatient correlation analyses result in a mean coefficient of r=.94 ±.06. Regional interpatient correlation coefficients of the study cohort are greater than 0.81. Radiotracer-specific and variant-specific subcohorts show no difference in the similarity between the images. Conclusions The static FMF could be a valid alternative to dynamic early-phase amyloid PET proposed in the literature, and a neurodegeneration biomarker for the diagnosis and classification of PPA in amyloid PET studies (AU)

18F-FDG PET/CT in a cardiac metastasis in a patient with history of malignant neuroectodermal tumour of the chest wall: Case report and review of the literature. / PET/TC con 18F-FDG en metástasis cardíaca en un paciente con antecedente de tumor neuroectodérmico maligno de la pared torácica (tumor de Askin): caso clínico y revisión de la literatura.

The case presented is a 25-year-old male with a malignant neuroectodermal tumour on the left chest wall (Askin tumour), treated with surgery after neoadyuvant chemotherapy and followed by consolidation chemotherapy. After 9 years of disease free survival, the patient developed an acute pulmonary embolism. The echocardiogram, thoracic CT, and cardiac MRI scans revealed a mass in the right atrium. Recurrence of an Askin tumour versus an atrium myxoma was suspected. 18F-FDG PET/CT showed an intense hypermetabolic right atrium mass with extension to the right ventricle highly suggestive of malignancy. The result of the histopathology examination after biopsy and subsequently exeresis of the right atrium mass was consistent with a metastasis of the primary tumour.

[Study of pulmonary lesions with (99m)Tc-Tetrafosmin and chest spect. Determination of uptake related factors, diagnostic value and prognosis]. / Estudio de las lesiones pulmonares con(99M)Tc-Tetrofosmin y SPECT de tórax. Determinación de los factores que intervienen en la captación, valor diagnóstico y pronóstico.

One hundred fifteen patients with 119 pulmonary lesions in which malignancy was suspected underwent a SPECT study with 99mTc-Tetrofosmin (TTF) to assess the possible factors involved in the uptake of the radiopharmaceutical. The TTF uptake rate in the lung tumor with respect to that of healthy tissue (TTF index) was evaluated in terms of: benignity and malignancy, histological type, stage, cell differentiation, size, necrosis, survival and the influence of P-glycoprotein (Pgp), detected by immunohistochemistry, on the TTF uptake. The mean TTF index in the 18 benign lesions studied was 1.01 0.05, while that of the 101 malignant lesions was 1.59 0.45 (p < 0.001), with a positive predictive value of 97.7% and a negative predictive value of 50%. The comparison of the histological types, degree of cell differentiation, necrosis and stage revealed no statistically significant differences. With respect to size, those tumors measuring > 3 cm showed greater uptake than smaller lesions. In patients with non-small cell lung cancer, a positive relationship was observed between the TTF index and survival, a circumstance that did not occur in patients with small cell lung cancer. In the cases in which the presence of Pgp was assessed, there was an inverse relationship between the TTF ratio and Pgp expression. In conclusion, thoracic SPECT with 99mTc-TTF has a high positive predictive value for the presence of lung cancer, although a negative study does not rule out the existence of the disease. The reason for this is the inverse relationship between 99mTc-TTF uptake and the density of Pgp expression.

[Correlation between 99m Tc-tetrofosmin uptake and P-glycoprotein expression in non-small-cell lung cancer]. / Correlación entre la captación de 99m Tc-tetrofosmín y la expresión de P-glicoproteína en cáncer de pulmón no microcítico.

UNLABELLED: We used thoracic SPECT to study the 99mTc-tetrofosmin (TF) uptake in patients with non-small-cell-lung-carcinoma (NSCLC). The results were compared with the percentage of P-glycoprotein (Pgp) found in flow cytometric analysis (FC) of samples of surgically-resected tumor tissue. MATERIAL AND METHODS: A total of 21 patients with NSCLC were studied by means 99mTC-TF and thoracic SPECT. Image analysis included the determination of the TF uptake rate in the lung mass with respect to that of healthy tissue of the contralateral lung. These rates were compared with the percentage of Pgp expression according to FC. FC analysis was also carried out in 16 samples of healthy lung tissue obtained from the patients. RESULTS: In healthy lung tissue, the mean Pgp expression according to FC was 4.58 +/- 1.87%. The cutoff value used to differentiate between Pgp positive and Pgp negative tumors was considered to be the mean plus two standard deviations (8.32). The Pgp-positive tumors (> 8.32%) presented significantly lower uptake levels (1.28 +/- 0.39) than the Pgp-negative lesions (1.66 +/- 0.33) (p = 0.029). CONCLUSIONS: There is a inverse correlation between the Pgp expression as determined by FC analysis and 99mTc-TF in NSCLC. Thus, this radiopharmaceutical provides rapid and non-invasive information on Pgp expression in these lesions.

Improved distribution of pulmonary flush solution to the tracheobronchial wall in pulmonary transplantation.

This report describes the experimental results obtained with conventional (pulmonary artery, PA) flushing versus retrograde perfusion (via left atrium, LA) using 99mTc-labeled macroaggregated albumin (MAA-99mTc) to ascertain the distribution throughout the tracheobronchial (TB) tree in 10 Large-White pigs. Lung preservation was achieved with 4 degrees C Euro-Collins solution (60 ml/kg) instilled via PA (n = 5) or LA (n = 5). Simultaneously, MAA-99mTc was given using the same respective route and the isotope uptake quantified at different TB levels after heart-lung block harvest and dissection of all tissue adjacent to TB: proximal and distal trachea and right and left main bronchi. Retrograde distribution resulted in a significantly higher 99mTc count compared to the PA route (p < 0.01).

Continuous prazosin administration in cirrhotic patients: effects on portal hemodynamics and on liver and renal function.

BACKGROUND & AIMS: Hepatic vascular resistance is influenced by alpha-adrenergic tone. The aim of this study was to investigate the effects of continuous blockade of alpha-adrenoceptors with prazosin on hemodynamics, liver function, and renal function and whether the association of propranolol or furosemide enhances the portal pressure lowering effect of prazosin. METHODS: Cirrhotic patients with portal hypertension were studied at baseline and after a 3-month course of prazosin (n = 18) or placebo (n = 10). RESULTS: No changes were observed in the placebo group. Prazosin decreased the hepatic venous pressure gradient (HVPG) while increasing hepatic blood flow. Liver function improved as shown by an increase in hepatic and intrinsic hepatic clearances of indocyanine green and galactose elimination capacity. A significant reduction in mean arterial pressure and systemic vascular resistance was associated with increases in plasma renin activity and aldosterone concentration and a decrease in glomerular filtration rate. The plasma volume increased significantly, and 6 patients developed edema. The association of propranolol (n = 8) but not furosemide (n = 7) to prazosin increased the reduction in HVPG and attenuated the increase in plasma renin activity. CONCLUSIONS: In cirrhotic patients, continuous prazosin administration reduces portal pressure and improves liver perfusion and function but favors sodium and water retention. The association of propranolol enhances the decrease in portal pressure, suggesting a potential benefit from this combined therapy.

[The usefulness of 99mTc-tetrofosmin in the diagnosis of pulmonary tumors. A preliminary assessment]. / Utilidad del 99mTc-tetrofosmin en el diagnóstico de tumoraciones pulmonares. Valoración preliminar.

We conducted a preliminary study of captation of the new radiopharmaceutical 99mTc-tetrofosmin in cases of primary carcinoma of the lung, analyzing the results of 5 cases studied before surgery with single photon emission tomography (SPECT) of the lung. The results obtained by imaging were compared with those from surgery. Tumor size ranged between 3.5 and 9 cm. In all cases the images showed that captation of the radiotracer by the neoplasm was satisfactory, leaving the area of the tumor clearly distinguishable from normal adjacent lung tissue and giving no signs of interference caused by absorption of 99mTc-tetrofosmin by contiguous structures (heart or liver). Based on these preliminary results we assert that SPECT of the lung using 99mTc-tetrofosmin may be useful in the clinical diagnosis of malignant lung tumors, although further research must determine to what extent the technique can be relied upon.

Effects of bisoprolol on left ventricular hypertrophy in essential hypertension.

Previous studies have shown that beta-adrenergic blocking drugs can reverse ventricular hypertrophy in patients with systemic hypertension. Thirty patients with essential hypertension and left ventricular hypertrophy were studied at baseline after withdrawing all previous treatments and after 6 months of treatment with 5-20 mg of bisoprolol, a new beta-selective agent, to assess its possible action on left ventricular mass. Three patients did not finish the study. Blood pressure was reduced to below 160/90 mmHg in 22 of the remaining 27 patients. At the end of follow-up, the left ventricular mass (echocardiography) was reduced from 308.1 +/- 89 g to 262.3 +/- 51 g (p < 0.001) and left ventricular mass index from 165 +/- 47.4 g/m2 to 141.03 +/- 26.7 g/m2 (p < 0.001). The ratio of E wave/A wave velocity of transmitral blood flow measured by Doppler increased from 0.86 +/- 0.44 to 1.07 +/- 0.45 (p = 0.005). Peak filling rate, derived from nuclear ventriculography, changed from 2.05 +/- 0.4 EDV/sec before the treatment to 2.23 +/- 0.47 EDV/sec after it (p = 0.0046). Serum lipids as well as other biochemical tests were unchanged. Left ventricular volumes and ejection fraction did not change, and treadmill exercise time increased from 343 +/- 125 seconds to 420 +/- 135 seconds (p = 0.002). Maximal systolic blood pressure during exercise decreased from 197.2 +/- 19.7 mmHg to 182.9 +/- 25.8 mmHg (p = 0.011). There were few side effects. We conclude that bisoprolol reduces left ventricular mass, preserves systolic function, and improves diastolic function of the left ventricle in hypertensive subjects with left ventricular hypertrophy.

Serum bone Gla protein as a marker of bone turnover in acromegaly.

Serum bone Gla protein, a sensitive and specific marker of bone turnover, was measured in 35 acromegalic patients (14 untreated, 8 clinically active, and 13 cured) and 21 controls. We also examined 10 acromegalic patients before and after transsphenoidal surgery. Untreated and clinically active acromegalic patients had significantly higher serum bone Gla protein concentrations than the control subjects. Other nonspecific biochemical markers of bone metabolism, such as urinary hydroxyproline and urinary calcium, were also present in significantly greater amounts in active acromegalic patients. After treatment, a significant decrease in levels was observed, with return to control levels. In acromegalic patients, positive correlations were found among serum bone Gla protein and serum growth hormone and serum insulin-like growth factor I levels, as well as among levels of insulin-like growth factor I and serum phosphorus, serum alkaline phosphatase, and urinary hydroxyproline. These results suggest that serum bone Gla protein is a sensitive marker of the action of growth hormone in bone metabolism in acromegaly, a role that is probably mediated by insulin-like growth factor I.