What are the main differential diagnoses of the intra orbital lesion in a child?
Dermoid cyst is the most common Vascular malformations including haemanioma, lymphangioma Optic nerve glioma - if bilateral most likely NF1 Inflammation (LCH) and infection Soft tissue malignancy: rhabdomyosarcoma
What is the most common malignancy involving the orbits in children? and what is the most common imaging features?
If globe is also included then retinoblastoma is the most common. However, the most common soft tissue orbital malignancy in childhood is rhabdomyosarcoma. Rhabdomyosarcoma of the orbits when small are relatively well defined but as they grow they become infiltrative soft tissue mass with variable enhancement and potentially erodes through the adjacent bones. Calcification is rare.