The developmental patterns of subcortical brain volumes in males and females observed in previous studies have been inconsistent. To help resolve these discrepancies, we examined developmental trajectories using three independent longitudinal samples of participants in the age-span of 8-22 years (total 216 participants and 467 scans). These datasets, including Pittsburgh (PIT; University of Pittsburgh, USA), NeuroCognitive Development (NCD; University of Oslo, Norway), and Orygen Adolescent Development Study (OADS; The University of Melbourne, Australia), span three countries and were analyzed together and in parallel using mixed-effects modeling with both generalized additive models and general linear models. For all regions and across all samples, males were found to have significantly larger volumes as compared to females, and significant sex differences were seen in age trajectories over time. However, direct comparison of sample trajectories and sex differences identified within samples were not consistent. The trajectories for the amygdala, putamen, and nucleus accumbens were most consistent between the three samples. Our results suggest that even after using similar preprocessing and analytic techniques, additional factors, such as image acquisition or sample composition may contribute to some of the discrepancies in sex specific patterns in subcortical brain changes across adolescence, and highlight region-specific variations in congruency of developmental trajectories.

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Because of a general lack of knowledge regarding the precise anatomy of the seminal vesicle system, efforts to use transurethral seminal vesiculoscopy (TSV) are currently constrained. We investigated 26 normal adult male specimens. Contrast medium was injected into the seminal vesicle system in 18 specimens and the openings of the ejaculatory ducts were examined with an operating microscope. India ink was injected into the urethra in four specimens to investigate the function of the ejaculatory duct valve. Another four specimens were examined histologically to identify the anatomical relationships of the seminal vesicle system. We found that the openings of the ejaculatory ducts were covered by the ejaculatory duct valve, which could be classified into two types and acted as a one-way valve. The apex of the seminal colliculus together with the right and left openings of the ejaculatory ducts formed a shape resembling an isosceles triangle. This could be used to locate the openings of the ejaculatory ducts during TSV. The ejaculatory ducts can be classified into two types according to their course. During surgery, efforts must be made to protect the ejaculatory duct valve. During inspection or surgery, the second segment and the angles of the ejaculatory ducts, particularly in Type I b and Type II cases, require particular attention.

Significant differences exist in NHP and craniocervical posture among skeletal class I, II, and III relationships in young Chinese children. Subjects with skeletal class II relationship tended to exhibit more extended head, and children with skeletal class III relationship often exhibited flexed head.

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