[A 2-year-old patient with acute proptosis]

Hemorrhage into an orbital lymphangioma can cause acute proptosis. A lymphangioma must be distinguished from acute threatening causes of rapidly developing proptosis in childhood, such as orbital cellulitis or malignant tumors (rhabdomyosarcoma). Imaging (magnetic resonance imaging, ultrasound, computed tomography) and histopathological evaluation are required for the final diagnosis. Immunohistochemical staining of lymphatic vessels with podoplanin can be useful for confirmation of the diagnosis.