@article{SchneiderHoehneSchneideretal.2022, author = {Schneider, Sonja Jasmin Maria and H{\"o}hne, Christian and Schneider, Martin and Schmitter, Marc}, title = {Photoacoustic tomography versus cone-beam computed tomography versus micro-computed tomography: Accuracy of 3D reconstructions of human teeth}, series = {PloS One}, volume = {17}, journal = {PloS One}, number = {12}, doi = {10.1371/journal.pone.0274818}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-301437}, year = {2022}, abstract = {Objectives In this in-vitro study, teeth were imaged using photoacoustic tomography (PAT), cone-beam computed tomography (CBCT), and micro-computed tomography (μ-CT). The study had aim: to identify the best wavelength for PAT images to determine the accuracy of the three imaging methods, and to determine whether PAT images of teeth can achieve acceptable reconstruction quality. Methods Nineteen human mandibular single-rooted incisors were extracted from patients with trauma or periodontitis. To determine the best wavelength for acquiring photoacoustic images, all 19 teeth were scanned in vitro with PAT, using different laser wavelengths between 680 and 960 nm. The images were analyzed using image analysis software. To assess the accuracy of PAT and compare it with the accuracy of CBCT, each tooth was also scanned in vitro using CBCT and the reference standard technique of μ-CT. Subsequently, three different three-dimensional models, one for each imaging technique, were created for each tooth. Finally, the three different three-dimensional models acquired for the same tooth were matched and analyzed regarding volume and surface. Results The highest quality tooth images were achieved using the 680 nm wavelength, which showed the best contrast ratio. The full geometry of the dental root (μ-CT compared with PAT) could be visualized with relative standard deviations of 0.12 mm for the surface and -7.33 mm3 for the volume (n = 19). The full geometry of the dental root (μ-CT compared with CBCT) could be visualized with relative standard deviations of 0.06 mm for the surface and -14.56 mm3 for the volume (n = 19). The difference between the PAT-μ-CT group and CBCT-μ-CT group regarding the total average of the root surface area was not significant (p>0.06). Conclusion Images, which were acquired using PAT at 680nm showed the best contrast ration, enabling the identification of dentin, cementum and the dental pulp. No significant differences were found between the PAT-μ-CT group and CBCT-μ-CT group regarding the total average of the RSA and the total volume. Thus, three-dimensional reconstructions based on in-vitro PAT are already of acceptable reconstruction quality.}, language = {en} } @article{GietzenKunzLuetkensetal.2022, author = {Gietzen, Carsten Herbert and Kunz, Andreas Steven and Luetkens, Karsten Sebastian and Huflage, Henner and Christopoulos, Georgios and van Schoonhoven, J{\"o}rg and Bley, Thorsten Alexander and Schmitt, Rainer and Grunz, Jan-Peter}, title = {Evaluation of prestyloid recess morphology and ulnar-sided contrast leakage in CT arthrography of the wrist}, series = {BMC Musculoskeletal Disorders}, volume = {23}, journal = {BMC Musculoskeletal Disorders}, number = {1}, doi = {10.1186/s12891-022-05241-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-301113}, year = {2022}, abstract = {Background In wrist arthrograms, aberrant contrast material is frequently seen extending into the soft tissue adjacent to the ulnar styloid process. Since the prestyloid recess can mimic contrast leakage in CT arthrography, this study aims to provide a detailed analysis of its morphologic variability, while investigating whether actual ulnar-sided leakage is associated with injuries of the triangular fibrocartilage complex (TFCC). Methods Eighty-six patients with positive wrist trauma history underwent multi-compartment CT arthrography (40 women, median age 44.5 years). Studies were reviewed by two board-certified radiologists, who documented the morphology of the prestyloid recess regarding size, opening type, shape and position, as well as the presence or absence of ulnar-sided contrast leakage. Correlations between leakage and the presence of TFCC injuries were assessed using the mean square contingency coefficient (r\(_{ɸ}\)). Results The most common configuration of the prestyloid recess included a narrow opening (73.26\%; width 2.26 ± 1.43 mm), saccular shape (66.28\%), and palmar position compared to the styloid process (55.81\%). Its mean length and anterior-posterior diameter were 6.89 ± 2.36 and 5.05 ± 1.97 mm, respectively. Ulnar-sided contrast leakage was reported in 29 patients (33.72\%) with a mean extent of 12.30 ± 5.31 mm. Leakage occurred more often in patients with ulnar-sided TFCC injuries (r\(_{ɸ}\) = 0.480; p < 0.001), whereas no association was found for lesions of the central articular disc (r\(_{ɸ}\) = 0.172; p = 0.111). Conclusions Since ulnar-sided contrast leakage is more common in patients with peripheral TFCC injuries, distinction between an atypical configuration of the prestyloid recess and actual leakage is important in CT arthrography of the wrist.}, language = {en} }