Optic Pit Presentation With Coexistent Orbital Cyst

Congenital Opticmeningoceles

Congenital optic nerve cystic-like malformations associated with normally developed globes are extremely rare. We describe 3 children who presented since birth with proptosis, and eye motility limitation. MRI showed in all cases that the intraorbital segment of the optic nerves was malformed with large cystic-like lesions in the intraconal segment of the orbit. In all cases, biopsies of the wall of the lesions were positive for glial fibrillary acidic protein. Since this protein is a neurobiomarker that exists only in astrocytes in the central nervous system, nonmyelinating Schwann cells of peripheral nerves, and enteric glial cells, we believe that these lesions represent true opticmeningoceles.

Unilateral optic disc pit associated with orbital cyst in a child

Optic disc pit and disc coloboma are common congenital anomalies. Both have been known to be associated with an orbital cyst. We report a case of a 6 month-old child who presented with unilateral progressive proptosis. Imaging investigations revealed a well-defined, intraconal, orbital cyst located close to the posterior surface of the globe displacing the optic nerve laterally. The cyst was excised and histopathological examination showed the cyst to have a lining of glial tissue, a thin epithelial lining, over a layer of collagenous connective tissue matrix. We hypothesize that colobomatous disc abnormalities and optic disc pits are different points on the same disease spectrum and can be associated with orbital cysts. Furthermore, our case points to the possible role of imaging the optic nerve in all cases of optic disc anomalies.