Neuroradiology Unit, Department of Neuroscienze, Salute Mentale e Organi di Senso (NESMOS), Sapienza University, Rome, Italy.
Department of Neuroradiology, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.
J Anat. 2021 May;238(5):1218-1224. doi: 10.1111/joa.13370. Epub 2020 Dec 5.
This study investigates the hypothesis that there is, during childhood, a disproportionate age-related expansion of the origin of temporalis muscle compared to the growth of the underlying skull. Lateral projections of 50 randomly selected 3D reformatted computerized tomographic (CT) scans (yielding 100 temporalis muscles) of children aged >0.6 to 15 years scanned for conditions that did not affect the shape of their head or face were windowed to provide the optimum delineation of temporalis muscle against the underlying bone. Vertical and anterior-posterior measurements of the muscle made independently by two observers were compared with those of the skull along the same planes. The development of the anterior temporal crest was also assessed. The intraclass correlation coefficient for differences in the measurements made by each observer ranged from good to excellent. The muscle and skull measurements were used to produce a ratio of muscle-to-skull lengths in both vertical and horizontal planes. Analysis of these ratios showed a statistically significant increase in the vertical reach of temporalis with age (Pearson correlation coefficient (R) =0.7826; p < 0.05) compared to the growth of the skull along the planes chosen for the study-but less so for its horizontal reach (R = 0.5073. p < .001). There were no significant differences between right/left or male/female measurements. There was also a substantial level of agreement between both observers in their assessment of the development of the temporal crest. The mean age of children in whom a fully formed temporal crest could be identified (10.6 years) was significantly greater (p < 0.001) than that of the 38 remaining subjects (6.0 years). These results confirm that there is, in response to increased masticatory/dietary demands during childhood, a disproportionate increase in the vertical and (to a lesser extent) horizontal reach of temporalis muscle over its origin from the temporal, frontal, sphenoid, and parietal bones compared the growth of the skull. It is proposed that surgical interference with this normal process is responsible for the soft tissue component of late-developing deformity that can occur following early (at 6-18 months of age) operations for the correction of trigonocephalic head shape associated with metopic synostosis.
本研究旨在验证一个假说，即在儿童时期，颞肌的起源相对于颅骨的生长会出现不成比例的年龄相关性扩张。对年龄在 0.6 岁以上至 15 岁之间的 50 名随机选择的 3D 重建 CT 扫描（共 100 个颞肌）进行了外侧投影，这些儿童的头部或面部均无影响其形状的疾病。扫描后对图像进行窗口处理，以提供颞肌与下方骨骼之间的最佳轮廓区分。由两位观察者独立进行的肌肉的垂直和前后测量与同一平面上的颅骨测量进行了比较。还评估了前颞嵴的发育情况。两位观察者之间的测量差异的组内相关系数范围从良好到极好。肌肉和颅骨的测量值用于产生垂直和水平平面上的肌肉与颅骨长度比。对这些比率的分析表明，随着年龄的增长，颞肌在垂直方向上的延伸与颅骨的生长相比具有统计学意义（皮尔逊相关系数（R）=0.7826；p<0.05）-但在水平方向上的延伸则不那么显著（R=0.5073，p<.001）。左右侧或男女侧测量值之间无显著差异。两位观察者在评估颞嵴的发育方面也存在相当大的一致性。可以识别完全形成的颞嵴的儿童的平均年龄（10.6 岁）明显大于（p<0.001）其余 38 名受试者的年龄（6.0 岁）。这些结果证实，在儿童时期咀嚼/饮食需求增加的情况下，颞肌相对于其在颞骨、额骨、蝶骨和顶骨上的起点的垂直和（在较小程度上）水平延伸会不成比例地增加，而颅骨的生长则相对较少。有人提出，手术干预这种正常过程是导致在早期（6-18 个月龄）进行治疗矢状缝早闭伴三角头畸形的矫正手术后，可能发生的迟发性发育畸形的软组织成分的原因。
