1 - Serviço de Neurorradiologia, Hospital Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central, Lisboa
- 45th ESNR Annual Meeting, 14-18 Setembro, Lisboa
- Neuroradiology (2022) 64 (Suppl 1):S1-S165 https://doi.org/10.1007/s00234-022-03012-w
INTRODUCTION: Although rare, congenital optic nerve anomalies are not uncommonly encountered in pediatric neuroradiology practice. While they may occur in isolation, they are frequently associated with other CNS developmental anomalies or systemic polymalformative syndromes. Isolated unilateral or asymmetrical anomalies with no significant functional vision changes can be an incidental finding on brain MRI. On the other hand, bilateral anomalies with significant visual impairment and syndromic cases with complex clinical pictures motivate an extensive diagnostic work-up, in which the neuroradiologist will play a crucial role.
METHODS: We provide a pictorial review of congenital optic nerve anomalies, focusing on its characteristic imaging findings, including frequently associated CNS developmental anomalies, and its differential diagnosis.
RESULTS: The main congenital optic nerve anomalies are optic nerve aplasia/hypoplasia and excavated optic disc anomalies, including optic disc coloboma and morning glory disc anomaly. Imaging findings of optic nerve hypoplasia consist of unilateral or bilateral thickness reduction of the optic nerve and optic chiasm. It is frequently associated with other CNS developmental anomalies, most often septo-optic dysplasia. Optic disc coloboma presents as a focal posterior defect in the globe with vitreous herniation. It may occur in isolation, with other globe abnormalities or in association with several syndromes, such as CHARGE (Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, and Ear anomalies/deafness) syndrome, Aicardi syndrome and renal-coloboma syndrome. MRI findings of morning glory disc anomaly consist of funnel-shaped morphology of the optic disc with elevation of the adjacent retinal surface, presence of abnormal tissue within the distal optic nerve and focal discontinuity of the uveoscleral coat. It is most frequently an isolated sporadic condition, although it can also be associated with sphenoidal cephalocele, Moyamoya disease and PHACE (Posterior fossa malformations, Haemangioma, Arterial anomalies, Coarctation of the aorta and cardiac defects, and Eye abnormalities) syndrome.
DISCUSSION & CONCLUSION: The neuroradiologist plays a very important role in the management of children with congenital optic nerve anomalies. Familiarization with the different congenital optic nerve anomalies, its characteristic imaging findings and main associations are the key for a confident diagnosis. Optic nerve hypoplasia should be differentiated from optic nerve atrophy, which can develop in diverse settings, such as in hereditary optic neuropathies. Importantly, optic disc coloboma and morning glory disc anomaly are distinct entities which can be differentiated on imaging. While colobomas are frequently associated with other developmental anomalies, morning glory disc anomaly is most often an isolated sporadic condition.
Palavras Chave: Neuroradiology; Pediatric neuroradiology; Head and neck imaging; MR imaging; Optic nerve; Optic nerve hypoplasia; Coloboma; Morning glory disc anomaly; Septo-optic dysplasia; Goldenhar syndrome; CHARGE syndrome; Aicardi syndrome; Moyamoya disease; Wolfram syndrome.