Revista Espanola De Medicina Nuclear最新文献

Objectives

The heart is one of the organs affected by sickle cell anemia (SCA). This prospective study has aimed to evaluate myocardial perfusion and left ventricle (LV) function in children with SCA by gated myocardial perfusion scintigraphy (G-MPS) and to compare the results with echocardiographic parameters.

Methods

Forty-three patients with SCA were evaluated by G-MPS and echocardiography. Myocardial perfusion and motion with thickening function were analyzed both visually and quantitatively. End-diastolic (EDV), end-systolic volumes (ESV), ejection fraction (EF), lung-to-heart (L/H) ratio were also calculated.

Results

None of the patients showed stress perfusion impairment in G-MPS. LV dilatation in 15 patients was observed both by G-MPS and echocardiography. EF values were within normal limits. Correlation between EF values calculated by two methods was not statistically significant. However, LV dilatation detected by both methods and EDV-ESV values in G-MPS were correlated to end-diastolic and end-systolic diameters calculated in echocardiography (p<0.05). M-Mode echocardiography revealed higher myocardial performance index (LV-MPI) in patients with LV dilatation. There was also a significant relationship between LV dilatation and frequent blood transfusions (>5/years) and acute chest syndrome (p<0.05).

Conclusion

Myocardial perfusion impairment in children with SCA is not frequently observed. Thus, performing the scintigraphy only in patients with cardiac symptoms should be considered. Since EF values of the children with SCA are not deteriorated in early stages, LV-MPI and LV dilatation should be considered as a significant parameter other than EF or perfusion data.

Objective

To establish an automated procedure for the preparation of sodium fluoride ¹⁸F injection using the resources available in our laboratory for the preparation of ¹⁸FDG and to analyze the repercussion of the conditioning column of the fluoride ion entrapment on the characteristics of the final product.

Material and method

The sequence of an ¹⁸FDG synthesis module prepared so that it traps the fluoride ion from the cyclotron in ion-exchange resin diluted with 0.9% sodium chloride. The final solution was dosified and sterilized in a final vial in an automatized dispensing module. Three different column conditioning protocols within the process were tested. Quality controls were run according to USP 32 and EurPh 6, adding control of ethanol levels of residual solvent and quality controls of the solution at 8 h post-preparation.

Results

Activation of the resin cartridges with ethanol and water was the chosen procedure, with fluoride ion trapping > 95% and pH around 7. Ethanol levels were < 5.000 ppm. Quality controls at 8 h indicated that the solution was in compliance with the USP 32 and EurPh 6 specifications.

Conclusion

This is an easy, low-cost, reliable automated method for sodium fluoride preparation in PET facilities with existing equipment for ¹⁸FDG synthesis and quality control.

Background

Myocardial perfusion imaging (MPI) provides highly valuable information for risk stratification and determination of optimal clinical management. The goal of the present study was to assess the prognostic value of myocardial perfusion SPECT for the prediction of future cardiac events in Asian population.

Methods

Five hundred and ten consecutive patients, who had undergone myocardial perfusion SPECT between 2005 and 2006, were prospectively followed-up. Patients’ data were collected from recorded files. Follow-ups were performed by scripted telephone interviews by a physician blinded to the patients’ MPI results and also from the hospital records. The total completed follow-ups consisted of 482 patients (follow-up rate, 94.5%).

Results

Over the mean follow-up period of 434 ± 62 days, 14 out of 482 patients (2.9%) died from cardiac events. Also in 61 patients (12.7%), the clinical condition led to a cardiac intervention (Percutaneous coronary intervention or coronary artery bypass grafting). Those patients without cardiac events on follow-up (including cardiac death or myocardial infarction) were younger and with less severity of MPI abnormalities. Severe MPI abnormalities (Summed Stress Score > 13) were found in 42.9% of those with cardiac death, while in 17.2% of those with myocardial infarction. The rate of cardiac death had a direct relationship with the severity of scan abnormalities, however, the same association was not found between the severity of MPI abnormality and the rate of myocardial infarction.

Conclusion

MPI is a valuable tool for risk stratification and prediction of future fatal cardiac events in Asian population. The risk of cardiac death as a mid-term outcome of coronary artery disease increases significantly with severity of MPI abnormalities.

We report the case of a 47 year-old woman with a history of non-Hodgkin's lymphoma. During the course of her disease, we performed various ^18FFDG PET/CT that identified several significant incidental findings. First, we incidentally identified a hypermetabolic nodule in the left thyroid lobe, whose final diagnosis was differentiated thyroid carcinoma. Second, metabolic activity was visualized in the thymus secondary to ablative treatment with radioiodine. This uptake disappeared in subsequent studies. Several papers have reported thymic rebound following chemotherapy but we have found only one case report of ^18FFDG uptake after radioiodine treatment. On the other hand, this case is of interest because it supports the benefit of studying the hypermetabolic thyroid nodules incidentally detected on the PET/CT performed for other reasons.

Objective

The aim of this study was to analyze cerebral perfusion and glucose metabolism in patients with cognitive impairment using cerebral blood flow ^99mTc-HMPAO SPECT and ¹⁸F-FDG PET/CT scans.

Material and methods

Twenty-two patients with cognitive impairment were included: 4 subjective memory complaints (SMC), 8 amnestic mild cognitive impairment (MCI), 5 prodromic Alzheimer's disease (AD) and 5 AD. In each clinical group, ^99mTc-HMPAO SPECT and ¹⁸F-FDG PET/CT scans were performed.

Results

^99mTc-HMPAO SPECT showed regions of cerebral hypoperfusion in 15 patients and was normal in 7 of the 22 patients. ¹⁸F-FDG PET/CT scan showed cerebral regional hypometabolism in 19 patients and was normal in the other 3 patients. The distribution of abnormalities on ^99mTc-HMPAO SPECT and ¹⁸F-FDG PET/CT scans was similar in 9 patients (2 SMC, 2 amnestic MCI, 2 prodromic AD, and 3 AD). In 6 patients (1 amnestic MCI, 2 prodromic AD, and 3 AD), FDG hypometabolism was more extensive than the cerebral hypoperfusion. Four patients (1SMC, 3 amnestic MCI) had an abnormal ¹⁸F-FDG PET/CT scan and normal ^99mTc-HMPAO SPECT. There were 3 patients (1 SMC 2, amnestic MCI) with normal ^99mTc-HMPAO SPECT and ¹⁸F-FDG PET/CT scans.

Conclusion

^99mTc-HMPAO SPECT and ¹⁸F-FDG PET/CT scans showed cerebral hypoperfusion and hypometabolism in patients with cognitive impairment, even in patients with clinical diagnosis of SMC. In patients with a normal cerebral blood flow SPECT, brain glucose cerebral hypometabolism can be detected. In some patients, the extension of FDG hypometabolism is more pronounced than that corresponding to the hypoperfusion area.