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Optimizar el radiomarcaje con 99mTc y 67Ga de nanopartículas de albúmina recubiertas con 4 polímeros sintéticos distintos y evaluar su estabilidad in vivoe in vitro,así como su biodistribución in vivotras su administración intravenosa.

La PET/TC con 11C-colina ha mostrado buenos resultados en la reestadificación del cáncer de próstata (CP) con antígeno específico prostático (PSA) elevado. Su uso con niveles bajos es controvertido. Nuestro objetivo fue evaluar la aportación de la 11C-colina PET/TC en pacientes con CP, recidiva bioquímica y PSA <1ng/ml.

El depósito cortical de amiloide, una seña de identidad de la enfermedad de Alzheimer, se ha observado en la hidrocefalia a presión normal (HPN). Nuestro objetivo fue comparar el patrón de retención de 11C-PIB PET/TC en pacientes con HPN y sujetos sanos.

The aim was to compare ventilation/perfusion SPECT lung scintigraphy (V/Q-SPECT) and computed tomography pulmonary angiography (CTPA) in patients with suspicion of pulmonary embolism (PE).

To evaluate the patterns of cerebral cortical distribution of 11C-PIB in patients with mild cognitive impairment (MCI).

Polymyalgia rheumatica (PMR) may present together with large vessel vasculitis (LVV), and frequently requires a more intensive therapy. The aim of the study was to evaluate the impact of 18F-FDG PET/CT in the diagnosis and management of LVV associated to PMR.

Attenuation artefacts decrease the specificity of myocardial perfusion single-photon emission computed tomography (SPECT). In this paper, the results of a prospective study evaluating the clinical applicability of attenuation and scatter correction in myocardial perfusion SPECT are presented. Of 607 patients in whom post-stress 99mTc-tetrofosmin myocardial perfusion SPECT was performed due to suspicion of coronary artery disease, 99 also underwent coronary angiography (CAG). A simultaneous emissiontransmission acquisition was performed. A multiple linear array of 153Gd sources and four independent energy windows were used for attenuation and scatter correction. A blind separate analysis of non-corrected (NC) and attenuation- and scatter-corrected (AC-SC) images was performed with scores of zero (no uptake) to three (normal uptake). The final diagnosis was based on CAG findings, and stenoses of 70 were considered to be significant. NC images had a sensitivity of 92 and a specificity of 46. In AC-SC images, the sensitivity decreased to 76, but the specificity increased to 71. The decrease in the sensitivity of AC-SC images was observed in all three coronary regions. Attenuation and scatter correction increased the specificity in the right coronary region, but decreased the specificity in the left anterior descending coronary region. In 13 of the 99 patients, AC-SC images showed false positive findings due to count deficiency in the anterior wall with normal CAG. The size of perfusion defects was decreased in AC-SC images (from 5.01±2.74 to 3.15±2.50 segments). The severity of perfusion defects was higher in NC (1.10±0.60) than in AC-SC (1.28±0.56) images. The combined evaluation of NC and AC-SC images was in agreement with the CAG findings in 79 of patients. It can be concluded that, when compared with NC images, AC-SC images improved the specificity in the right coronary region and decreased the sensitivity in all three coronary regions. Attenuation and scatter correction may generate anterior wall defects with normal CAG. The analysis of AC-SC images cannot be used alone for the diagnosis of coronary artery disease. In the clinical setting, combined NC and AC-SC images are recommended for the evaluation of post-stress myocardial perfusion SPECT.

Diabetes is a major frequent cause of atherosclerosis vascular disease. Arterial calcification in diabetic patients is responsible for peripheral vascular involvement. Molecular imaging using 18F-sodium fluoride (18F-NaF) positron emission tomography (PET)/computed tomography (CT) has been recently proposed as a marker to study the in vivo mineralization process in the atheroma plaque. A 69-year-old man with a history of type 2 diabetes and no clinical evidence of peripheral arterial disease underwent an 18F-NaF PET/CT scan. A linear, well-defined 18F-NaF uptake was detected along the femoral arteries. In addition, the CT component of the PET/CT identified an unsuspected “tram-track” calcification in his femoral arteries, suggestive of medial calcification (Mönckeberg's sclerosis). In other vascular territories, focal 18F-NaF uptake was also detected in carotid and aorta atheroma plaques. Molecular imaging with 18F-NaF PET/CT might provide new functional information about the in vivo vascular calcification process in diabetic patients.

Choledochocholedochostomy (CC) over a T-tube is a well-recognized technique for biliary reconstruction in orthotopic liver transplantation (OLT). Bile leaks after T-tube removal are common, having a significant morbidity. The aim of this study was to evaluate the utility of hepatobiliary scintigraphy (HSB) for diagnosing bile leaks in liver transplant patients who develop abdominal pain after T-tube removal. Twenty consecutive patients (14 males, 6 females; mean age 44 years) were studied. The interval between T-tube removal and HBS ranged from 8 to 120 h. Hepatobiliary scintigraphy was carried out after the intravenous injection of 185 MBq 99Tcm-mebrofenin. A final diagnosis of bile leak was based on surgical, endoscopic retrograde cholangiopancreatography (ERCP) and ultrasound data, and clinical outcome. There were 13 patients with and 7 without bile leaks. On the scintigraphic images, bile leaks were defined as activity outside the biliary tract which moved along the right paracolic gutter, or the progressive accumulation of activity related to fluid collections as seen on ultrasound. Nine of 12 patients needed surgical repair; the other 3 were treated with endoscopic sphincterotomy. One patient with a negative HBS developed an abdominal abscess after aspirative puncture of a biloma. In the seven patients without bile leaks, all scintigrams showed normal biliary transit of activity. A diagnosis of no bile leaks was based on clinical follow-up in five patients and by ERCP in two patients. Based on these results, we conclude that HBS is an effective method for the diagnosis of bile leaks after T-tube removal in liver transplant patients.

A 51-year-old woman with a medullary thyroid carcinoma (MTC) presented with a palpable nodule in the right breast. Serum calcitonin was 1,453 pg/ml and carcinoembryonic antigen was 201 ng/ml. Cervical ultrasound and bone scintigraphy were normal. Computed tomography (CT) showed nodules in the right breast and anterior thoracic wall and a hypodense lesion in the right hepatic lobe. Histology of the breast nodule confirmed metastasis from MTC. To evaluate the metabolic activity of these lesions, 18F-fluorodeoxiglucose positron emission tomography-CT (FDG-PET/CT) scan was requested. Axial fused images revealed high FDG uptake by the breast and thoracic wall nodules and the right hepatic lobe. FDG-PET/CT also showed uptake in sacrum and right iliac bone, undetected by CT and bone scintigraphy. After seven cycles of sorafenib PET/CT became negative. Calcitonin decreased to 82.5. A PET/CT performed 6 months later remained negative. This is the first published image of the complete metabolic response of MTC to sorafenib therapy using FDG-PET/CT.