Benedikt Hager1,2,3, Markus M. Schreiner4, Sonja M. Walzer4, Lena Hirtler5, Vladimir Mlynarik1, Martin Zalaudek1, Andreas Berg6, Xeni Deligianni7,8, Oliver Bieri7,8, Reinhard Windhager4, Vladimir Juras1, and Siegfried Trattnig1
1Department of Biomedical Imaging and Image-guided Therapy, High Field MR Centre, Medical University of Vienna, Vienna, Austria, 2CD Laboratory for Clinical Molecular MR Imaging, Vienna, Austria, 3Austrian Cluster for Tissue Regeneration, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria, 4Department of Orthopedics and Trauma-Surgery, Medical University of Vienna, Vienna, Austria, 5Center for Anatomy and Cell Biology, Division of Anatomy, Medical University of Vienna, Vienna, Austria, 6Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, 7Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland, 8Department of Biomedical Engineering, University of Basel, Allschwil, Switzerland
In this study, we analyzed the T2* anisotropy and mono- vs. bi-exponentiality of T2* decay of Achilles and patellar tendons in vitro with a variable echo time sequence, ultrashort echo times and microscopic resolution and compared the results with histological findings. A total of four human Achilles tendons and four patellar tendons were measured at their maximum and minimum dipolar interaction (0°, 55°). In addition, one Achilles tendon and one patellar tendon were measured at 11 fiber-to-field angles (0,10,20,30,40,50,60,70,80,90°) each in order to study the change in T2* values at these angles.