Dolenšek Janez, Cvetko Erika, Snoj Žiga, Meznaric Marija
Faculty of Medicine, Institute of Anatomy, University of Ljubljana, Korytkova 2, 1000, Ljubljana, Slovenia.
Institute of Radiology, University Medical Centre Ljubljana, Zaloška 7, 1000, Ljubljana, Slovenia.
Surg Radiol Anat. 2017 Sep;39(9):1053-1059. doi: 10.1007/s00276-017-1826-y. Epub 2017 Feb 18.
Fusion of the atlas with the occipital bone is a rare congenital dysplasia known as occipitalization of the atlas, occipitocervical synostosis, assimilation of the atlas, or atlanto-occipital fusion. It is a component of the paraxial mesodermal maldevelopment and commonly associated with other dysplasias of the craniovertebral junction. External auditory canal atresia or external aural atresia is a rare congenital absence of the external auditory canal. It occurs as the consequence of the maldevelopment of the first pharyngeal cleft due to defects of cranial neural crest cells migration and/or differentiation. It is commonly associated with the dysplasias of the structures derived from the first and second pharyngeal arches including microtia. We present the coexistence of the occipitalization of the atlas and congenital aural atresia, an uncommon combination of the paraxial mesodermal maldevelopment, and defects of cranial neural crest cells. The association is most probably syndromic as minimal diagnostic criteria for the oculoariculovertebral spectrum are fulfilled. From the clinical point of view, it is important to be aware that patients with microtia must obtain also appropriate diagnostic imaging studies of the craniovetebral junction due to eventual concomitant occipitalization of the atlas and frequently associated C1-C2 instability.
寰椎与枕骨融合是一种罕见的先天性发育异常，称为寰椎枕化、枕颈融合、寰椎同化或寰枕融合。它是轴旁中胚层发育不良的一个组成部分，通常与颅颈交界区的其他发育异常相关。外耳道闭锁或外耳道先天性缺失是一种罕见的先天性外耳道缺失。它是由于颅神经嵴细胞迁移和/或分化缺陷导致第一鳃裂发育异常的结果。它通常与源自第一和第二鳃弓的结构发育异常相关，包括小耳畸形。我们报告了寰椎枕化与先天性耳闭锁并存的情况，这是一种轴旁中胚层发育不良与颅神经嵴细胞缺陷的罕见组合。这种关联很可能是综合征性的，因为满足了眼耳脊椎综合征的最低诊断标准。从临床角度来看，重要的是要意识到，由于最终可能并发寰椎枕化和频繁相关的C1-C2不稳定，小耳畸形患者也必须进行颅颈交界区的适当诊断性影像学检查。
