MARCELO TATIT SAPIENZA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
10 resultados
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- Prevalence of exclusive lower extremity metastases at 18F-NaF PET/CT(2015) ORDONES, Monique Beraldo; VALADARES, Agnes Araujo; DUARTE, Paulo Schiavom; SADO, Heitor Naoki; LIMA, Marcos Santos; CARVALHO, Giovanna; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoAbstract Objective: To evaluate the prevalence of exclusive lower extremity metastases, specifically in the femur and below the knee, observed at 18F-NaF PET/CT. Materials and Methods: One thousand consecutive PET/CT studies were retrospectively evaluated for the presence of exclusive uptake in lower extremities suggesting metastatic involvement. The presumptive diagnoses based on such uptakes were subsequently obtained by evaluation of other imaging studies. Results: No exclusive uptake suggestive of metastasis below the femur was observed in the present series. Exclusive uptake was observed in the proximal femur with a presumptive diagnosis of metastasis in two patients. Conclusion: The prevalence of exclusive metastasis below the femur is low and scanning from head to knees is appropriate in most cases.
- Clinical and Dosimetric Variables Related to Outcome After Treatment of Graves' Disease With 550 and 1110 MBq of I-131(2015) SAPIENZA, Marcelo Tatit; COURA-FILHO, George Barberio; WILLEGAIGNON, Jose; WATANABE, Tomoco; DUARTE, Paulo Schiavom; BUCHPIGUEL, Carlos AlbertoTherapy of Graves' hyperthyroidism (HTG) with I-131 is still mostly performed on an empirical basis. The present study was carried out to evaluate clinical and dosimetric variables associated with outcome in HTG therapy, which could contribute to planning and defining the most appropriate activity to be administered. Methods Patients with HTG were randomly assigned to therapy with 555 MBq (15mci) or 1110 MBq (30 mCi) of I-131. Estimation of thyroid radiation absorbed dose was made according to MIRD methodology. Success was defined as clinical/laboratory euthyroidism or hypothyroidism one year after therapy. The association between clinical, laboratory, and dosimetric variables with 1-year outcome was measured using bivariate analysis, followed by logistic regression. Results Ninety-one patients included completed the follow-up. Therapeutic success was observed in 77 (84.6%) of them, in a greater proportion when 1110 MBq of I-131 was administered as compared with 550 MBq (94.8% vs 77.4%, P = 0.02). Besides administered activity, multivariate analysis indicated that outcome was related to patient age and gland mass. A higher therapeutic success rate was achieved with doses greater than 300 Gy as compared with doses less than 300 Gy (89% vs 60%, P = 0.01). Conclusion Administered activity, age, and gland mass were related to the outcome. Radiation absorbed dose, although not significant according to multivariate analysis, may be used as a quantitative parameter in therapy planning, with a target dose of 300 Gy. In cases where a rapid and efficient response to radioiodine treatment is required, adoption of a simplified protocol employing high activities is justified.
- Comparison of standardized uptake values measured on 18F-NaF PET/CT scans using three different tube current intensities(2015) VALADARES, Agnes Araujo; DUARTE, Paulo Schiavom; WOELLNER, Eduardo Bechtloff; COURA-FILHO, George Barberio; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoObjective: To analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on 18FNaF PET/CT scans. Materials and Methods: A total of 254 18F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Results: Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: The three tube current values yielded similar results for SUV calculation.
conferenceObject EVALUATION OF MDRD4, CKD-EPI AND MODIFIED COCKCROFT-GAULT EQUATIONS TO ESTIMATE GLOMERULAR FILTRATION RATE IN THE ELDERLY RENAL TRANSPLANTED RECIPIENTS(2015) DAVID-NETO, Elias; KAMADA, Triboni Ana Heloisa; RAMOS, Fernanda; AGENA, Fabiana; BRAMBATE, Carvalhinho Lemos Francine; TATIT, Sapienza Marcelo; ALTONA, Marcelo; NAHAS, William Carlos- Effects of Thyroid Hormone Withdrawal and Recombinant Human Thyrotropin on Glomerular Filtration Rate During Radioiodine Therapy for Well-Differentiated Thyroid Cancer(2015) COURA-FILHO, George Barberio; WILLEGAIGNON, Jose; BUCHPIGUEL, Carlos Alberto; SAPIENZA, Marcelo TatitBackground: Renal function is related to thyroid hormonal status, and glomerular filtration rate (GFR) seems to be impaired in patients with hypothyroidism. The aim of this work was to evaluate quantitatively the effect of hypothyroidism on GFR using a Cr-51-EDTA radioisotope assay. Methods: Twenty-eight patients without known renal disease or dysfunction who had been referred for radioiodine therapy (RIT) after total thyroidectomy were enrolled in this study and divided into two groups. Group A underwent thyroid hormone withdrawal (THW) resulting in hypothyroidism, while group B underwent recombinant human thyrotropin (rhTSH) stimulation and hence remained euthyroid. GFR was assessed by Cr-51-EDTA before and after THW or rhTSH. Results: No clinical differences were observed between the two groups. The meanSD GFRs were 94 +/- 19mL/min/1.73m(2) before THW and 76 +/- 16mL/min/1.73m(2) after THW for group A (p=0.009), and 91 +/- 18mL/min/1.73m(2) before rhTSH and 93 +/- 15mL/min/1.73m(2) after rhTSH for group B (p=0.613). The percent decrease in GFR during hypothyroidism is approximately 18-22%. Conclusion: GFR decreases in patients with normal kidney function during THW for RIT, and rhTSH preserves GFR in these patients. This GFR impairment following thyroidectomy is related to hypothyroidism due to a significant reduction in thyroid hormone levels and is not due to a rise in the TSH level.
conferenceObject MDRD4 Equation Is Better Than CKD-EPI, Cockroft-Gault and Nankivell Equations to Estimate Glomerular Filtration Rate in Renal Transplantation(2015) DAVID-NETO, E.; TRIBONI, A.; RAMOS, F.; AGENA, F.; LEMOS, F.; SAPIENZA, M.; NAHAS, W.- Dose calibrator linearity test: 99mTc versus 18F radioisotopes(2015) WILLEGAIGNON, José; SAPIENZA, Marcelo Tatit; COURA-FILHO, George Barberio; GARCEZ, Alexandre Teles; ALVES, Carlos Eduardo Gonzalez Ribeiro; CARDONA, Marissa Anabel Rivera; GUTTERRES, Ricardo Fraga; BUCHPIGUEL, Carlos AlbertoObjective: The present study was aimed at evaluating the viability of replacing 18F with 99mTc in dose calibrator linearity testing. Materials and Methods: The test was performed with sources of 99mTc (62 GBq) and 18F (12 GBq) whose activities were measured up to values lower than 1 MBq. Ratios and deviations between experimental and theoretical 99mTc and 18F sources activities were calculated and subsequently compared. Results: Mean deviations between experimental and theoretical 99mTc and 18F sources activities were 0.56 (± 1.79)% and 0.92 (± 1.19)%, respectively. The mean ratio between activities indicated by the device for the 99mTc source as measured with the equipment pre-calibrated to measure 99mTc and 18F was 3.42 (± 0.06), and for the 18F source this ratio was 3.39 (± 0.05), values considered constant over the measurement time. Conclusion: The results of the linearity test using 99mTc were compatible with those obtained with the 18F source, indicating the viability of utilizing both radioisotopes in dose calibrator linearity testing. Such information in association with the high potential of radiation exposure and costs involved in 18F acquisition suggest 99mTc as the element of choice to perform dose calibrator linearity tests in centers that use 18F, without any detriment to the procedure as well as to the quality of the nuclear medicine service.
- Effects of Duodenal-Jejunal Bypass Liner (EndoBarrierA (R)) on Gastric Emptying in Obese and Type 2 Diabetic Patients(2015) MOURA, Eduardo Guimaraes Hourneaux de; LOPES, Guilherme Sauniti; MARTINS, Bruno da Costa; ORSO, Ivan Roberto Bonotto; COUTINHO, Artur Martins Novaes; OLIVEIRA, Suzana Lopes de; SAKAI, Paulo; GALVAO-NETO, Manoel dos Passos; SANTO, Marco Aurelio; SAPIENZA, Marcelo Tatit; CECCONELLO, Ivan; BUCHPIGUEL, Carlos AlbertoThe duodenal-jejunal bypass liner (DJBL) is a promising technique for treating obesity and type 2 diabetes mellitus (T2DM). However, despite promising results, its mechanism of action has not been elucidated. It is thought to promote changes in gastric emptying owing to the neuro-endocrine axis. The aim of this paper was to study DJBL-induced changes in gastric emptying and the relationship of those changes with weight loss and T2DM. Twenty-five patients with obesity and T2DM met inclusion criteria. Scintigraphic gastric emptying testing was performed prior to implantation, 16 weeks after implantation, and 4 weeks after removal. The average gastric retention was compared between tests, to examine the relationship between gastric emptying and those who lost more than 10 % of total body weight. Similarly, we compared average gastric retention between those who achieved a glycated hemoglobin target lower than 7 %. Average gastric retention was greater after DJBL implantation compared with the baseline (first hour, 74 +/- 16.3 %, p = 0.001; second hour, 45 +/- 25 %, p < 0.001; fourth hour, 15.8 +/- 15 %, p < 0.001). There was no difference between the baseline and 4 weeks after device removal (fourth hour, p = 0.057). Gastric retention was similar between patients who achieved T2DM control and those who did not (p = 0.73). Additionally, no difference was seen between patients who lost more than 10 % of body weight and those who did not (p = 0.275). DJBL delays gastric emptying but is reversible after withdrawal. The changes in gastric emptying have no relationship to weight loss and T2DM control.
- Visualization of Lymph Nodal and Hepatic Metastases of Medullary Thyroid Carcinoma on F-18-Fluoride PET/CT(2015) VALE, Romulo Hermeto Bueno do; MARIN, Jose Flavio Gomes; DUARTE, Paulo Schiavom; SAPIENZA, Marcelo Tatit; BUCHPIGUEL, Carlos AlbertoF-18-fluoride uptake in soft tissue metastases has been previously described. Herein, we report a case of F-18-fluoride uptake in lymph nodal and hepatic metastases of medullary thyroid carcinoma. Simultaneous CT showed calcified lesions in these regions.
conferenceObject Predicting dosimetry for therapy using imaging analogs of therapeutic radiopharmaceuticals: An uncertainty and sensitivity analysis applicable to Theranostics(2015) JOSEFSSON, Anders; HOBBS, Robert; PLYKU, Donika; HUANG, Kevin; WILLEGAIGNON, Jose; COURA FILHO, George; DUARTE, Paulo; SAPIENZA, Marcelo; SGOUROS, George