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In the pursuit of closing the gap between nanometrology and nanofabrication, we investigate the use of advanced optical far field methods for sub-wavelength parameter reconstruction. With the goal of establishing a hybrid evaluation scheme connecting different methods and including different information channels, we performed comparison measurements on a silicon line grating sample with buried as well as not buried surface relief lines. To this end, the results of our measurement are in good agreements with each other, and the collected structure data is feasible to be used for hybrid evaluation.

We report a custom microscope setup whose mechanical and optical components are adjusted by the means of an alignment autocollimator (AAC). Residual centring and angular misalignments of the components towards the microscope’s optical axis are below 500 μm and 1 mrad, respectively. We further perform measurements of dot structures with diameters close to the diffraction limit (nominal diameter = 200 nm; chrome on glass mask) as suitable measures for the evaluation of the microscope’s adjustment and to determine/ visualize the optical aberrations, which affect the image formation of microscopes.

The estimation of respiratory rates from contineous respiratory signals is commonly done using either fourier transformation or the zero-crossing method. This paper introduces another method which is based on the autocorrelation function of the respiratory signal. The respiratory signals can be measured either directly using a flow sensor or chest strap or indirectly on the basis of the electrocardiogram (ECG). We compare our method against other established methods on the basis of real-world ECG signals and use a respiration-based breathing frequency as a reference. Our method achieved the best agreement between respiration rates derived from directly and indirectly measured respiratory signals.

Improved expansion of stents using high-pressure implantation technique with subsequent antiplatelet therapy has improved patient outcome regarding the incidence of subacute stent thrombosis, bleeding complications and restenosis. Whether high-pressure implantation per se guarantees adequate stent expansion remains unclear. The aim of the study was to determine (1) stent expansion after high-pressure implantation technique and (2) whether stent expansion influences rate of target lesion revascularization within 6 months of follow-up. One hundred Palmaz-Schatz stents were implanted in 98 lesions (91 native vessels, 7 graft vessels) of 94 patients using high-pressure implantation technique (balloon pressure 12-20 atm). Stent expansion was investigated using intravascular ultrasound imaging (IVUS). Clinical follow-up of the patients was performed for 6 months. After implantation, stent/mean reference ratio was 0.81 +/- 0.16. Noncompliant balloons used for implantation were chosen by angiographic criteria. Mean balloon/reference ratio was 1.08 +/- 0.22; therefore balloons were not undersized. Additional balloon dilataion using higher pressures and/or larger balloons based on IVUS criteria and subsequent IVUS measurements was performed in 52 patients (55%); in these patients, stent expansion improved from 79 +/- 16 to 91 +/- 15% (mean +/- SD) of average reference areas (p < 0.002). Within the 6 months' clinical follow-up, target lesion revascularization was performed in 19 patients (20%). The only prognostic factors for the development of in-stent restenosis requiring target lesion revascularization were the vessel size (p < 0.05) and the extent of plaque distal to the stents (p < 0.05). Implantation of Palmaz-Schatz stents using high-pressure technique does not guarantee adequate stent expansion. Additional dilatation with higher pressures and/or larger balloons improves stent expansion. The size of the stented vessel and the extent of plaque at the distal stent end (residual outflow stenosis) but not the degree of stent expansion were predictors for target lesion revascularization within 6 months' follow-up.