Diagnostic Performance of 99mTc-Methoxy-Isobuty-Isonitrile (MIBI) for Risk Stratification of Hypofunctioning Thyroid Nodules: A European Multicenter Study.

99mTc-MIBI (MIBI) imaging is able to exclude malignancy of hypofunctioning thyroid nodules (TNs) with high probability but false positive results are frequent due to low specificity. Therefore, pre-test selection of appropriate TNs is crucial. For image evaluation visual and semiquantitative methods (Washout index, WOInd) are used. Aim of this study was to evaluate the diagnostic performance of MIBI imaging in hypofunctioning TNs with indeterminate fine-needle aspiration cytology results in a multicentric European setting. Patients with hypofunctioning TNs, EU-TIRADS 4 or 5, Bethesda III/IV and MIBI imaging were included. For visual evaluation the intensity of MIBI uptake in the TN was compared to normal thyroid tissue. 358 patients with 365 TNs (n = 68 malignant) were included. Planar imaging (SPECT) showed a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 96% (94%), 21% (22%), 22% (15%), 96% (96%), and 35% (32%). The WOInd (38.9% of all cases, optimal cutoff: -19%) showed a sens 100% (spec 89%, PPV 82%, NPV 100%, ACC 93%). For hypofunctioning TNs at intermediate or high risk with indeterminate cytology, a MIBI negative result on visual evaluation is an effective tool to rule-out thyroid malignancy. The semi-quantitative method could considerably improve overall diagnostic performance of MIBI imaging.

Papillary thyroid carcinoma in a hyper-functional thyroid nodule.

The authors reported the case of 69 years old woman presented with subclinical hyperthyroidism. 99m-Tc pertechnetate scan showed the abnormal focus of hot uptake in the left lobe, suggestive of a hyperfunctioning toxic thyroid nodule. Surgical treatment was advised because of the size of the nodule as a more applicable solution. Histological findings showed papillary thyroid carcinoma.

The Significance of Thallium-201-Chloride SPECT Myocardial Perfusion Imaging in the Management of Patients With Stable Chronic Coronary Artery Disease.

BACKGROUND: Patients with stable coronary artery disease (CAD) can be evaluated for myocardial viability by examining reverse redistribution of Thallium-201 (201TI) through cardiac scintigraphy. There is limited knowledge about association of a reverse redistribution with favorable cardiac outcomes. In this study, we hypothesized that higher left ventricular ejection fraction (LVEF), lower myocardial necrosis, fewer ischemic events, and less angina will be associated with reverse redistribution of 201TI imaging. METHODS: Adult patients with stable CAD included in this study underwent exercise-redistribution Thallium single-photon emission computed tomography (SPECT) and were followed for one year. LVEF and regional wall motion abnormalities were evaluated with echocardiography, exercise duration by bicycle testing, and myocardial ischemia and viability by Thallium SPECT. RESULTS: We studied 159 patients (87 men, 72 women, median age 60 years, range: 38-84) with well-developed collaterals. Those with reverse redistribution on SPECT (n = 61, 38.3%) had significantly better exercise tolerance (⩾85%; P < .001). Subjects with reverse redistribution had better LVEF (P < .001), wall motion parameters (P < .001), a lower degree of myocardial necrosis (P < .05), less angina during follow-up (P = .02), and fewer ischemic events whether treated with OMT or PCI (P < .001). CONCLUSIONS: Reverse redistribution of 201Tl on scintigraphic images is a predictor of myocardial viability. Evidence from our study suggests that optimally treated chronic CAD patients with reverse redistribution may have lower likelihood of future adverse cardiovascular events and better prognosis.

The grade of acute thymus involution in neonates correlates with the duration of acute illness and with the percentage of lymphocytes in peripheral blood smear. Pathological study.

In various stressful conditions, the thymus is subjected to incidental involution, mostly due to the thymocytolytic effect of secreted glucocorticosteroids. The aim of this study was to examine acute thymic involution in sick neonates and to compare the morphological grade with some clinical and laboratory parameters. The influence of the illness on thymus tissue was investigated in 100 neonates who were treated and died in a neonatology intensive care unit. The preterm infants (n = 73) were born before the 37th week of gestation. Analysis of 57 placentas showed inflammation in 32% and circulatory disturbances in 23% of the cases. The causes of death were confirmed by autopsy: 35 were preterm infants with respiratory distress syndrome without infection, 22 were malformed, and 10 had birth trauma or asphyxia. In contrast, 29 of the preterm infants had an infection, mostly pneumonia or sepsis, and 4 of the term infants had such infections. Acute thymus involution was histologically graded (0-4) according to the method of van Baarlen (see text). Resting state (grade 0) was found in 25 of 38 neonates who lived <12 h. In 13 of 38 neonates who lived <12 h, thymus involution suggested prenatal stress. The grade of thymus involution related to the duration of illness (p < 0.001). Placental inflammation was associated with features of thymus involution (p < 0.048). Infection as a cause of death was connected to advanced thymus involution (p < 0.001). In preterm newborns, infection was more often connected with acute thymus involution than was respiratory distress syndrome (p < 0.003). Among the parameters measured in all available peripheral blood samples taken 24 h before death, only the lymphocyte count related to the grade of acute thymus involution (p < 0.05), with an increase in percentage of lymphocytes in peripheral blood smears from grade 0 to 2 and a decrease from grade 2 to 4. Although the white blood cell count is highly variable, a low percentage of lymphocytes might be a sign of advanced accidental thymus involution following acute stress.