ObjectivesTo assess the clinical relevance of T2 relaxation times, measured by 3D triple-echo steady-state (3D-TESS), in knee articular cartilage compared to conventional multi-echo spin-echo T2-mapping.MethodsThirteen volunteers and ten patients with focal cartilage lesions were included in this prospective study. All subjects underwent 3-Tesla MRI consisting of a multi-echo multi-slice spin-echo sequence (CPMG) as a reference method for T2 mapping, and 3D TESS with the same geometry settings, but variable acquisition times: standard (TESSs 4:35min) and quick (TESSq 2:05min). T2 values were compared in six different regions in the femoral and tibial cartilage using a Wilcoxon signed ranks test and the Pearson correlation coefficient (r). The local ethics committee approved this study, and all participants gave written informed consent.ResultsThe mean quantitative T2 values measured by CPMG (mean: 46±9ms) in volunteers were significantly higher compared to those measured with TESS (mean: 31±5ms) in all regions. Both methods performed similarly in patients, but CPMG provided a slightly higher difference between lesions and native cartilage (CPMG: 90ms→61ms [31%],p=0.0125;TESS 32ms→24ms [24%],p=0.0839).Conclusions3D-TESS provides results similar to those of a conventional multi-echo spin-echo sequence with many benefits, such as shortening of total acquisition time and insensitivity to B1 and B0 changes.Key points• 3D-TESS T2mapping provides clinically comparable results to CPMG in shorter scan-time.• Clinical and investigational studies may benefit from high temporal resolution of 3D-TESS.• 3D-TESS T2values are able to differentiate between healthy and damaged cartilage.

In conclusion, this study demonstrates a ciprofloxacin-induced reversible reduction of the normalized sodium MR imaging signal and the GAG CEST effect in the Achilles tendon of healthy volunteers. Changes in sodium MR imaging and GAG CEST in men may reflect a decrease of GAG content in the Achilles tendon after ciprofloxacin intake.

It is well established that climatic and geographic factors control the stable isotope composition of precipitation. These relationships are of major importance in climate studies, in particular for the interpretation of isotope data from paleoclimate archives.Austria's topography is highly complex, mainly due to the large mountain ranges of the Alps. The Alps divide Austria into several distinct climate zones. The particular geographical condition and climate situation of Austria result in complex stable isotope patterns which are still not fully understood. In order to improve our understanding, we investigate the influence of meteorological and geographical conditions on isotope records for several Austrian sampling sites. The Austrian Network of Isotopes in Precipitation and Surface Waters (ANIP) has recorded monthly isotope and meteorological data since 1973. In the present study, we determined baseline data which can be used in future stable isotope studies. An Austrian Meteoric Water Line (AMWL), based on 18 amount-weighted isotope values (weighted by the monthly precipitation amount) of 14 stations, was found to be δD = 7.5 δ O + 3.2. The slope and the intercept are close to, but lower than corresponding values of the Global Meteoric Water Line, most probably as a result of secondary evaporation during precipitation. Local Meteoric Water Lines (LMWLs) of single stations have been computed on a monthly and an amount-weighted annual basis. The correlation between altitude and amount-weighted annual

Purpose To evaluate: (1) the feasibility of MR microscopy T 2 * mapping by performing a zonal analysis of spatially matched T 2 * maps and histological images using microscopic in‐plane pixel resolution; (2) the orientational dependence of T 2 * relaxation of the meniscus; and (3) the T 2 * decay characteristics of the meniscus by statistically evaluating the quality of mono‐ and biexponential model. Methods Ultrahigh resolution T 2 * mapping was performed with ultrashort echo time using a 7 Tesla MR microscopy system. Measurement of one meniscus was performed at three orientations to the main magnetic field (0, 55, and 90°). Histological assessment was performed with picrosirius red staining and polarized light microscopy. Quality of mono‐ and biexponential model fitting was tested using Akaike Information Criteria and F‐test. Results (1) The outer laminar layer, connective tissue fibers from the joint capsule, and the highly organized tendon‐like structures were identified using ultra‐highly resolved MRI. (2) Highly organized structures of the meniscus showed considerable changes in T 2 * values with orientation. (3) No significant biexponential decay was found on a voxel‐by‐voxel–based evaluation. On a region‐of‐interest–averaged basis, significant biexponential decay was found for the tendon‐like region in a fiber‐to‐field angle of 0°. Conclusion The MR microscopy approach used in this study allows the identification of meniscus substructures and to quantify T 2 * with a voxel resolution approximately 100 times higher than previously reported. T 2 * decay showed a strong fiber‐to‐field angle dependence reflecting the anisotropic properties of the meniscal collagen fibers. No clear biexponential decay behavior was found for the meniscus substructures.