Magnetic resonance imaging of the small bowel with the true FISP sequence: intra- and interobserver agreement of enteroclysis and imaging without contrast material

Purpose: This study aimed to determine the reliability of magnetic resonance imaging (MRI) without luminal contrast medium versus MR enteroclysis for evaluating small bowel pathology, to compare MRI and MRE findings per observer, and to compare these findings with those of an expert reader in order to determine the influence of luminal contrast medium on morphological evaluations. Conclusion: The use of luminal contrast medium bowel improves reliability for measuring bowel wall thickness and for the diagnosis and grading of obstruction when evaluating the small bowel. (C) 2009 Elsevier Inc. All rights reserve

Aerodynamic particle size analysis of aerosols from pressurized metered-dose inhalers: Comparison of andersen 8-stage cascade impactor, next generation pharmaceutical impactor, and model 3321 aerodynamic particle sizer aerosol spectrometer

The purpose of this research was to compare three different methods for the aerodynamic assessment of (1) chloroflurocarbon (CFC)-fluticasone propionate (Flovent), (2) CFC-sodium cromoglycate (Intal), and (3) hydrofluoroalkane (HFA)-beclomethasone dipropionate (Qvar) delivered by pressurized metered dose inhaler. Particle size distributions were compared determining mass median aerodynamic diameter (MMAD), geometric standard deviation (GSD), and fine particle fraction <4.7 μm aerodynamic diameter (FPF<4.7 μm). Next Generation Pharmaceutical Impactor (NGI)-size distributions for Flovent comprised finer particles than determined by Andersen 8-stage impactor (ACI) (MMAD=2.0±0.05 μm [NGI]; 2.8±0.07 μm [ACI]); however FPF<4.7 μm by both impactors was in the narrow range 88% to 93%. Size distribution agreement for Intal was better (MMAD=4.3±0.19 μm (NGI), 4.2±0.13 μm (ACI), with FPF<4.7 μm ranging from 52% to 60%. The Aerodynamic Particle Sizer (APS) undersized aerosols produced with either formulation (MMAD=1.8±0.07 μm and 3.2±0.02 μm for Flovent and Intal, respectively), but values of FPF<4.7 μm from the single-stage impactor (SSI) located at the inlet to the APS (82.9%±2.1% [Flovent], 46.4%±2.4% [Intal]) were fairly close to corresponding data from the multi-stage impactors. APS-measured size distributions for Qvar (MMAD=1.0±0.03 μm; FPF<4.7 μm=96.4% ±2.5%), were in fair agreement with both NGI (MMAD=0.9±0.03 μm; FPF<4.7 μm=96.7%±0.7%), and ACI (MMAD=1.2±0.02 μm, FPF<4.7 μm=98%±0.5%), but FPF<4.7 μm from the SSI (67.1%±4.1%) was lower than expected, based on equivalent data obtained by the other techniques. Particle bounce, incomplete evaporation of volatile constituents and the presence of surfactant particles are factors that may be responsible for discrepancies between the techniques