Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Solna, Sweden.
Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
J Neurosci Res. 2020 Nov;98(11):2166-2177. doi: 10.1002/jnr.24702. Epub 2020 Aug 10.
Although the neuroanatomy of transgender persons is slowly being charted, findings are presently discrepant. Moreover, the major body of work has focused on Western populations. One important factor is the issue of power and low signal-to-noise (SNR) ratio in neuroimaging studies of rare study populations including endocrine or neurological patient groups. The present study focused on the structural neuroanatomy of a Non-Western (Iranian) sample of 40 transgender men (TM), 40 transgender women (TW), 30 cisgender men (CM), and 30 cisgender women (CW), while assessing whether the reliability of findings across structural anatomical measures including gray matter volume (GMV), cortical surface area (CSA), and cortical thickness (CTh) could be increased by using two back-to-back within-session structural MRI scans. Overall, findings in transgender persons were more consistent with sex assigned at birth in GMV and CSA, while no group differences emerged for CTh. Repeated measures analysis also indicated that having a second scan increased SNR in all regions of interest, most notably bilateral frontal poles, pre- and postcentral gyri and putamina. The results suggest that a simple time and cost-effective measure to improve SNR in rare clinical populations with low prevalence rates is a second anatomical scan when structural MRI is of interest.
虽然跨性别者的神经解剖结构正在慢慢被描绘出来，但目前的发现存在差异。此外，大多数研究都集中在西方人群。一个重要的因素是在包括内分泌或神经患者群体在内的罕见研究人群的神经影像学研究中，权力和信噪比 (SNR) 低的问题。本研究集中于对 40 名跨性别男性 (TM)、40 名跨性别女性 (TW)、30 名顺性别男性 (CM) 和 30 名顺性别女性 (CW) 的非西方 (伊朗) 样本的结构神经解剖结构进行研究，同时评估通过使用两次在会话内的结构 MRI 扫描，是否可以提高包括灰质体积 (GMV)、皮质表面积 (CSA) 和皮质厚度 (CTh) 在内的结构解剖学测量结果的可靠性。总的来说，在 GMV 和 CSA 方面，跨性别者的发现与出生时分配的性别更一致，而在 CTh 方面没有出现组间差异。重复测量分析还表明，在所有感兴趣的区域，包括双侧额叶极、额中和后中央回和苍白球，第二次扫描都增加了 SNR。结果表明，对于罕见的临床人群，当结构 MRI 感兴趣时，增加具有低患病率的罕见临床人群的 SNR 的简单、省时且具有成本效益的措施是进行第二次解剖扫描。
