Skyscan ctan

Bone and mineralized callus structure and density were evaluated by Micro-CT. A SkyScan 1176 compact X-ray MicroCT scanner (Bruker, Belgium) was used for all scans with the beam set at 90 kV and 270μA. Scans were reconstructed at 18μm isotropic resolution. All samples were scanned within 3 days after sacrifice. All reconstructions were performed using Skyscan NRecon Program (Bruker, Belgium). Measurements and analysis were conducted using SkyScan Dataviewer (Bruker, Belgium) and SkyScan CTan (Bruker, Belgium).
Mineralized tissues were classified into either mineralized bone or callus depending on the density of the intact cortical bone in the ulna. Based on previously published researches, the density of callus considered to be mineralized was 35%–70% of the maximum density of the intact cortical bone[18 (link)]. The density of intact mineralized bone was determined to be over 70% of the maximum intensity of the cortical bone. Cylindrical volume of interest (VOI) with a length of 10mm was used to analyzed the fracture zone, centered at the midpoint of the fracture in longitudinal view.
Volume and density were calculated for mineralized bone and mineralized callus. Morphometric parameters measured were as follows: mineralized callus volume, mineralized callus density, bone volume and bone mineral density.

Adult zebrafish were anesthetized, culled according to standard protocols. Each individual was genotyped by fin-clipping and fixed and stored in 4% paraformaldehyde (PFA) dissolved in phosphate-buffered saline (PBS) at 4°C. Micro-CT analysis (Skyscan 1272, Bruker, Kontich, Belgium) was performed as described before (Csete et al., 2019 (link)). Whole-body scans were acquired using a 100 kV and 100 μA X-ray source without filter followed by reconstruction with the SkyScan NRecon software (Bruker, Kontich, Belgium), resulting in a 5 μm or 20 μm voxel size. Further analysis was performed using the Skyscan CTAn (Bruker, Kontich, Belgium). The lower threshold of binary images was set to an absolute value of 95 or 105. Quantitative analysis was performed on the precaudal vertebraes of the fish using an axial cylinder of a diameter of 1,000 μm around the center of vertebraes. Determined parameters were percent mineralized volume (MV/TV) in the total volume of interest and percent mineralized area (MA/TA) in every section.

The high-resolution micro-computed tomography (μCT) was used to scan each left tibia and isometric resolution was set at 9 μm. The x-ray energy was set to 80 kV and 100 μA. The three-dimensional (3D) imaging was recurred using the SkyScan NRecon procedure and SkyScan CTAn software (Bruker, Billerica, MA, United States). Trabecular bone analysis was performed in the specific zone of 0.5 mm below the growth plate of the tibia with a height of 1 mm. Trabecular morphometry was evaluated by calculating the bone volume/tissue volume (BV/TV), bone mineral density (BMD), number of trabeculae (Tb.N., mm^–1), trabecular separation (Tb.Sp., mm), cortical thickness (Ct.Th), and cortical bone mineral content (Ct.BMC).