Brain Computed Tomography Compared with Facial 3-Dimensional Computed Tomography for Diagnosis of Facial Fractures.

OBJECTIVES: To compare the detection of facial fractures and radiation dose between brain computed tomography (CT) and facial 3-dimensional (3D) CT in pediatric patients who have experienced a trauma. STUDY DESIGN: Four hundred pediatric patients who experienced a trauma and underwent immediate brain CT and facial 3D CT between January 2016 and June 2016 were included in this retrospective study. Two reviewers independently analyzed and determined the presence of the facial fractures of 8 anatomic regions based on brain CT and facial 3D CT over a 1-week interval. Suggested treatment decisions for facial fractures seen on brain CT and facial 3D CT were evaluated by one physician. The facial 3D CT scans, interpreted by a senior radiologist, were considered as the reference standard. Diagnostic performance, radiation dose, and interobserver agreement of the CT scans were evaluated. RESULTS: Brain CT showed a high sensitivity (94.1%-96.5%), high specificity (99.7%-100%), and high accuracy (98.8%-99.0%) in both reviewers, and performed as well as did facial 3D CT (P ≥ .25). The suggested treatment decision was not different between the brain CT and facial 3D CT findings. The agreements between the reference standard and the reviewers, and between reviewers 1 and 2 were excellent (k = 0.946-0.993). The mean effective radiation doses used in brain CT (3.6 mSv) were significantly lower than those in brain CT with facial 3D CT (5.5 mSv) (P < .001). CONCLUSIONS: Brain CT showed acceptable diagnostic performance and can be used as the first-line imaging tool in the workup of pediatric patients with suspected facial fractures.

Establishment of a pheasant (Phasianus colchicus) spermatogonial stem cell line for the production of interspecies germ line chimeras

Background Spermatogonial stem cells (SSCs) are important for the production of interspecies germ line chimeras. The interspecies germ cell transfer technique has been suggested as a way to conserve endangered birds. Our objective was to develop a technique for restoring endangered birds by developing interspecies germ line chimeras between pheasant (Phasianus colchicus) and chicken (Gallus gallus) with SSCs. Results SSCs were isolated from the surgically removed testis of a pheasant. Growth conditions for pheasant SSCs were established by co-culturing STO (SIM mouse embryo-derived thioguanine and ouabain resistant) cells and pheasant SSCs. The colony-forming cells divided and proliferated stably to yield an established SSC line. Pheasant SSCs showed strong reactivity for GDNF family receptor alpha1 (GFRa1) marker. Finally, production of germ line chimeras was attempted by transferring pheasant SSCs into recipient embryos. Although final embryo survival was 5.6% (20/354), the initial survival rate was 88% (312/354). To measure the percent transfer of donor SSC to gonads, the pheasant SSCs were labeled with PKH 26 fluorescent dye. We observed 30% donor cells and 9.48% c-kit/CD117-positive cells in the gonads of recipient chickens. Donor SSCs were thus stably engrafted in the recipient gonads. Conclusions This study showed that SSCs can be used as a tool for the conservation of endangered birds and the production of germ line chimeras. Our findings yield insights into how we may use the pheasant spermatogonial stem cell line for efficient production of interspecies germ line chimeras and ultimately, to the restoration of endangered birds.