Hepatic parenchymal enhancement during triple-phase helical CT: can it be used to predict which patients with breast cancer will develop hepatic metastases?

PURPOSE: To evaluate the efficacy of hepatic enhancement characteristics for identification of patients with breast cancer who are at risk for future hepatic metastases. MATERIALS AND METHODS: Triple-phase helical computed tomography (CT) was performed in 60 patients with known breast cancer without visible hepatic metastases. Peak hepatic attenuation and enhancement, and attenuation and enhancement at 25 and 30 seconds were obtained. Ratios of hepatic attenuation or enhancement at 25 and 30 seconds to peak hepatic attenuation or enhancement were calculated. A Wilcoxon rank sum test was used to compare patients with and those without subsequent hepatic metastases. RESULTS: During a mean 18-month follow-up, 18 patients (30%) developed hepatic metastases. Decreases in peak hepatic attenuation and enhancement and increases in hepatic attenuation and enhancement ratios at 25 and 30 seconds were seen in patients who developed metastases compared with those who did not (P < .05). When corrected for chemotherapy interval, these differences were not statistically significant. Using a threshold value of 0.40 or more for the enhancement ratio at 30 seconds resulted in sensitivity of 28%, specificity of 92%, and accuracy of 55%. CONCLUSION: Patients with breast cancer who develop subsequent hepatic metastases have higher relative hepatic arterial perfusion during triple-phase CT; however, after correction for chemotherapy interval, this difference was not statistically significant. Threshold values cannot be used reliably to identify patients who will develop metastases.

[Operator exposure levels in nuclear medicine studies]. / Livelli di esposizione dell'operatore in alcune indagini di medicina nucleare.

In diagnostic examinations performed in nuclear medicine, radio-isotopes with a relatively short half-life are used, the quantity varying according to the type of examination. After administration of the labelled substance, the patient becomes a large source of ionizing radiations. During the course of a scintigraphic examination, the operator is obliged to go near the couch to assist the patient in the positions and will therefore inevitably be in this radiation field. The paper reports the radio-activity levels recorded at gonad and eye levels of the operator in positions most frequently held during the course of the most commonly performed scintigraphic examinations using a G.E. STARCAM 500 A gamma-camera.

Auger and pixe microanalysis of intrauterine devices (IUDs).

Auger Emission Spectroscopy (AES) and Particle Induced X-ray Emission (PIXE) analysis were employed in a study on the calcification and oxidation processes of the copper wires used in Intra-Uterine Device (IUDs) contraceptives. A strong copper release (approximately 50 micrograms/day) has been observed in the first year of IUDS application during the high device antifertility effect. The copper release is reduced with the IUD-use time, because of the calcification process on the surface by organic liquids. This effect produces a drastic reduction in the contraceptive efficiency, and a new IUDs replacement is needed after about 2 years of use. Auger, X-ray spectrometry and scanning electron microscopy (SEM) have been used to investigate the lifetime and efficiency of IUDS in order to understand the surface modification of copper wire during its permanence in the intrauterine environment.

PIP: Auger Emission Spectroscopy (AES) and Particle Induced X-ray Emission (PIXE) analysis were employed in a study on the calcification and oxidation processes of the copper wires used in IUDs. A strong copper release (approximately 50 mcg/day) was observed in the 1st year of IUD use, during the high device antifertility effect. Copper release is reduced over time due to the calcification process on the surface by organic liquids. This effect produces a drastic reduction in contraceptive efficiency and new IUDs are necessary after 2 years of use. Auger, x-ray spectrometry, and scanning electron microscopy have been used to investigate IUD lifetime and efficiency in order to understand the surface modifications of copper wire during its performance in the intrauterine environment. (author's modified).

[Analysis of bioactive intrauterine devices using high energy proton induced X-Rays (Pixe) and scanning microscopy (Sem) (Author's transl)]. / Analyse des DIU bioactifs par la methode Pixe et Sem.

PIP: It has been amply demonstrated that the effectiveness of copper IUDs is superior to that of inert IUDs. The decreased risk of pregnancy depends not only on the mechanical action on the endometrium, but on modification of the biochemical environment. Goal of this study is to analyze the physico-chemical process which intervenes on the surface of copper IUDs, using high energy proton induced X-rays and scanning microscopy. The devices examined were removed during routine examinations from patients who had worn them for periods going up to 3 years. Data gathered showed that there are 2 phases in the physico-chemical process. During the first 8 months of use a deposit of a granular structure and rich in potassium, chlorine, calcium, and probably sulphur, appears on the copper wire; during the same period the emission of copper is very important, whence the increased contraceptive effectiveness. During the second phase, going from 1 to 3 years, there is a marked process of calcification which induces a progessive and irreversible neutralization of the contraceptive action of bioactive IUDs.^ieng