Medial angular dermoid
Swelling since birth adjacent to the medial canthus of the left orbit with slow increase in size over the years.
Loading Stack -
0 images remaining
Left sided superficially located space occupying lesion is noted involving the preseptal region of the medial aspect of the left upper eyelid extending to the region of the inner canthus. It is still separable from the region of the left lacrimal sac. It flattens against the maxillary process of the left frontal bone and the proximal aspect of the left nasal bone. No intra-orbital or intra-cranial extension could be seen. It showed non-enhancing average MDCT density of – 130 HU (fat).
The above described features are those of a left sided fat containing lesion most consistent with a medial angular dermoid.
Dermoid cysts represent the most common congenital lesion of the orbit. The most common location is at the frontozygomatic suture (80%) followed by the nasal aspect of upper orbit at the frontoethmoidal suture. Orbital dermoid cysts could be diagnosed if the fatty components are found within it. Some dermoid cysts appears with fluid levels at the superior component of the lesion is a transparent field of fat and the lower component is relatively dense. It is called the "fat-floating" sign.