Demonstration of tissue alterations by ultrasonography, magnetic resonance imaging and spectroscopy, and histology in breast cancer patients without lymphedema after axillary node dissection.

Estimates of the incidence of arm swelling after axillary lymph node dissection for breast cancer range from 10 to 37%. Yet the subjective sensation of edema is described in at least 54% of patients. The purpose of this research was to examine the structural changes occurring in the subcutaneous tissue that might explain these subjective complaints using multiple imaging modalities. Two female cadavers with unilateral breast amputation and axillary dissection were studied. The dermal and subcutaneous layers of both arms were visualized with high frequency ultrasonography, and magnetic resonance imaging and spectroscopy (MRS), and tissue biopsies were taken for histological evaluation. On the operated side, ultrasound imaging showed a hyperechogenic subcutis and the fat-to-water relationship in adipose cells was higher as measured by MRS. Dissection of the arms revealed structural adipose tissue changes, which were confirmed by microscopic evaluation.

Trace anion determination in concentrated hydrofluoric acid solutions by two-dimensional ion chromatography II. Method performance study with a hydroxide eluent and a low noise suppressor.

The two-dimensional ion exclusion chromatography/ion chromatography (ICE-IC) approach is considered to be the method of choice for the determination of trace anions in concentrated hydrofluoric acid (48-50%, w/w). In order to achieve lower detection limits, this method was for the first time used with electrolytically generated and purified hydroxide eluents in combination with a low noise electrochemical suppressor. Compared to carbonate based eluents, the achieved gain in peak height sensitivity for chloride, sulfate, nitrate and phosphate is a factor of 6, 7, 16 and 13, respectively. The instrumental detection limits, based on the background noise, are 2, 0.2, 0.4 and 1.4 microg/kg HF 50% (w/w) for the same anions. Their method detection limits, calculated according to SEMI, are all within the 6-10microg/kg HF 50% (w/w) range and thus at least 10 times lower than the current Tier C grade requirements. The chromatographic run time could be shortened with some 10 min by the use of a relatively fast high-capacity hydroxide selective anion exchange column.

A key to understanding postoperative lymphoedema: a study on the evolution and consistency of oedema of the arm using ultrasound imaging.

Post-mastectomy oedema is a very serious complication that, in the course of time, will transform into fibrotic tissue. The aim of our study is to evaluate when and in which layer liquid oedema transforms into fibrotic tissue. To do so, ultrasonographic images were taken of 22 patients and 9 control women at the shoulder and 10 cm proximal and distal from the olecranon, with the images then being scanned and imported into a computer program to determine echogenicity of the dermis, subcutis, subcutis on dermal side and subcutis on fascial side. Statistical analyses were performed by means of the Wilcoxon test and a Student's t-test. No significant differences (P< or =0.05) were found for the different parameters in the control group. In the experimental group: significant differences in perimeter, skinfold, thickness of dermis and subcutis were found. Although not significant, subcutaneous tissue was more echogenic on the oedematous side, with significant hyperechogenicity at the fascial subcutaneous layer. This indicates that fibrotic tissue develops distally in the forearm.

Determination of trace amounts of cadmium, lead, copper and zinc in natural waters by inductively coupled plasma atomic emission spectrometry with thermospray nebulisation, after enrichment on Chelex-100.

Enrichment on Chelex-100, followed by evaporation when necessary, was used for the pre-concentration of Cd, Pb, Cu and Zn from natural waters. The measurements were carried out with inductively coupled plasma atomic emission spectrometry using a thermospray nebulisation system to reach the required sensitivity. The detection limits corresponding to three times the standard deviation of the blank (in 1% v/v HNO3) after a 30-fold enrichment are 0.02 microgram l-1 for Cd, 0.33 microgram l-1 for Pb and 0.03 microgram l-1 for Cu and Zn. Matrix effects, which are fairly serious with thermospray nebulisation, were taken into account by using the standard additions method. Results obtained for several river water samples were compared with those found by analysis of the non-enriched sample with inductively coupled plasma mass spectrometry or graphite furnace atomic absorption spectrometry. In all instances the agreement was satisfactory.