Diagnostic value of early postoperative MRI and diffusion-weighted imaging following trans-sphenoidal resection of non-functioning pituitary macroadenomas.

AIM: To establish the value of early contrast-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in differentiating residual pituitary adenoma from postoperative surgical changes. MATERIALS AND METHODS: Thirty patients with non-functioning pituitary macroadenomas, who were undergoing trans-sphenoidal adenomectomy, were prospectively studied. Patients were imaged with both MRI and DWI in the early postoperative period, as well as 6-months post-surgery. Patterns of postoperative contrast enhancement were described (non-enhancement, peripheral enhancement, and nodular enhancement). Apparent diffusion coefficient (ADC) maps were utilised to select the region of interest (ROI) for ADC calculations. RESULTS: Seventeen patients had postoperative surgical granulation tissue and 13 had residual adenoma based on the 6 months follow-up imaging. Mean ADC values of postoperative granulation tissue and residual adenoma were 1.476±0.476×10-3 mm2/s and 0.855±0.190×10-3 mm2/s, respectively, in the early postoperative period, and 1.357±0.416×10-3 mm2/s and 0.829±0.201×10-3 mm2/s, respectively, at the 6-month follow-up. ADC values of granulation tissue were significantly different from that of residual adenoma at both time points (p<0.001). Sensitivity, specificity, positive and negative predictive values of early MRI were 84.6%, 94.1%, 91.7%, and 88.9% respectively, and of early DWI were 91%, 97%, 94.3%, and 93%, respectively. CONCLUSION: Early postoperative DWI after trans-sphenoidal resection of pituitary macroadenomas may be more helpful than early MRI in differentiating residual adenoma from post-surgical changes.

Validation of a lactic acid- and citric acid-based antimicrobial product for the reduction of Escherichia coli O157: H7 and Salmonella on beef tips and whole chicken carcasses.

The objectives of this study were to determine the effects of a lactic acid- and citric acid-based antimicrobial product on the reduction of Salmonella on whole broiler carcasses during processing and the reduction of Salmonella and Escherichia coli O157:H7 on beef trim. Freshly harvested broiler carcasses were inoculated with an inoculum of Salmonella strains to yield a 10(5) CFU/ml pathogen load on the surface of the carcass. The beef tips were inoculated as well with an inoculum of either E. coli O157:H7 or Salmonella to yield 10(4) CFU/100 cm(2). After 30 min for attachment, the broiler carcasses were treated with Chicxide applied for 5 s via a spray or immersed in Chicxide for 5, 10, or 20 s. Broiler carcasses were rinsed in poultry rinse bags with 400 ml of Butterfield's phosphate buffer in which Salmonella was enumerated from the diluents and Butterfield's phosphate. Chicxide significantly reduced Salmonella by 1.3 log CFU/ml with spray treatment and 2.3 log CFU/ml for all dip treatments. Following 30 min of attachment, the beef tips were placed into a spray cabinet with either Beefxide or sterilized water (control) and sprayed at 1 ft/2.5 s chain speed at 40 lb/in(2). The external surface of each beef tip was swabbed (100 cm(2)) to determine pathogen loads. Beefxide significantly reduced E. coli O157:H7 by 1.4 log CFU/100 cm(2) and Salmonella by 1.1 log CFU/100 cm(2) (P < 0.05) compared with the control samples.