Tissue quantification of radioiodine thyroid uptake in humans by an isotopic imaging technique on slides.

BACKGROUND: Thyroid metabolism involves iodine, which allows us to use radioactive iodine for diagnostic and therapy purposes. The efficiency of radioiodine therapy depends on several parameters; the ability of thyroid tissue to uptake radioactive iodine is one of them. OBJECTIVE: The objective of this work is to quantify the radioactive iodine uptake on thyroid tissue. METHODS: In this work, we developed a method to quantify the in vivo uptake of iodine-131 on sections of thyroid glands removed by thyroidectomies. We performed an analysis of histological sections of the thyroid tissue by beta imaging. We had the opportunity to quantify the fixed radioactivity and to analyze its distribution in the thyroid gland, thanks to the good spatial resolution available with the type of detector used. RESULTS: The results gave a high image resolution showing the heterogeneity of iodine-131 fixation by the thyroid tissue. We were able to quantify the tissue radioactivity in mega Becquerel (MBq) per volume unit. CONCLUSION: This work has shown that the direct quantification of the thyroid tissue uptake is possible using the beta imaging system.

[The fracture risk assessment tool (FRAXTM), where are we in Tunisia?]. / Le score FRAX®, ou on est en Tunisie.

BACKGROUND: The fracture risk assessment tool (FRAXTM), published in February 2008, is developed based on the use of clinical risk factors with or without bone mineral density tests. AIM: To calculate the FRAX tool in a cohort of Tunisian patients in whom bone mineral density (BMD) was assessed by dual X ray absorptiometry (DXA); to correlate this score to osteoporotic fracture and to BMD assessment and to propose a threshold for therapeutic intervention. METHODS: In a cross sectional study of 582 patients older than 40 years, in whom a BMD measurement by DXA has been performed between January 2006 and December 2009, clinical risk factor for osteoporotic fracture and the occurrence of a prior fragility fracture were assessed. The French version of the FRAX tool was used. Threshold for pharmacological intervention was evaluated by ROC curve. RESULTS: Patients were aged 62.3 ± 10.4 years. They were female in 91.2% of cases. BMD measurement was under 2.5 standard deviation in 53.2%. Osteopenia was noted in 29.2% of cases and BMD was normal in 17.4 % of cases. Osteoporotic fractures were observed in 38.2% of cases. Major osteoporotic fractures (FOM) (hip, vertebra, radius occurred in 82% of cases. The FRAX® score calculated with T-score was 8.55 ± 8.54% for the FOM and 3.02 ± 6.37% for femoral neck (FN), while it was 7.81 ± 6.45% for the FOM and 2.58 ± 3.97% for the FN if calculated without T-score with a significant difference (p <10-3). For the patients having T-score under 2.5 SD, FRAX score was 11.39 ± 10.32% for the FOM and 4.74 ± 8.13% for the FN if calculated with T-score and it was 9.18 ± 6.95 % for the FOM and 3.19 ± 4.11 % if calculated without T-score. The score FRAX was correlated to BMD (r=0,53, p <10-3) and to fracture prevalence (p < 10-3). The threshold of therapeutic intervention was fixed to 30% for the FOM and 7% for the FN. CONCLUSION: Our study confirms the usefulness of the FRAX score in the prediction of fracture risk in Tunisian population. The determination of therapeutic threshold intervention requires other prospective and larger studies with medico-economic analyses.

Isotopic exploration of hepatic hydrothorax: ten cases.

OBJECTIVE: The aim of this retrospective study was to evaluate the performance of peritoneal scintigraphy for the diagnosis of peritoneopleural communication in patients with cirrhosis and to discuss its role in therapeutic management. PATIENTS AND METHODS: Ten patients with cirrhosis and pleural effusion were included in this study. Cirrhosis was due to viral hepatitis in eight patients, auto-immune disease in one patient and of unknown origin in one. The pleural effusion was right-sided in nine patients and bilateral in one. 99m-technetium sulfur colloid peritoneal scintigraphy was performed in all patients. RESULTS: Scintigraphy revealed peritoneopleural communication in nine patients. In four patients, radioactivity appeared in the pleural cavity within a few minutes after injection of the radiotracer. In three of them, a large diaphragmatic defect was demonstrated by ultrasonography, magnetic resonance imaging or thoracoscopy. Complete response to medical treatment was observed in four patients. Scintigraphy revealed rapid radioactivity migration in four patients; diuretic treatment led to resolution of the hydrothorax in one of them. Three patients whose hydrothorax was refractory to medical treatment were treated by pleurodesis with talc. Resolution of the hydrothorax was achieved in one of them. CONCLUSION: Peritoneal scintigraphy is a simple non-invasive method enabling confirmation of peritoneopleural communication in cirrhotic patients. The importance of the diaphragmatic defect can also be evaluated, providing a significant contribution to therapeutic decision-making.

Large diaphragmatic defect as the cause of hydrothorax in a cirrhotic patient: demonstration with peritoneal scintigraphy and magnetic resonance imaging.

A 52-year-old man with history of post-hepatitic cirrhosis presented with ascitis and respiratory distress. Chest X-ray on admission showed a large right hydrothorax. Thoracentesis yielded a large volume of a clear transudate fluid. Peritoneal scintigraphy showed rapid migration of radiotracer into the right pleural cavity, confirming the abdominal origin of the pleural fluid and suspecting a large diaphragmatic defect. MR imaging study using ultrafast sequences confirmed the large diaphragmatic defect.