Orbital Space-occupying Congenital Naso-orbital Encephalocele

ABSTRACT

Purpose@#A case of a huge ethmoid sinus and orbital cyst causing ocular deviation initially diagnosed as a mucocele-like cyst and after orbitotomy eventually discovered to be a naso-orbital encephalocele is described.Case summary: A 5-year-old male with no previous medical history presented with a palpable mass in the medial canthus area with left exodeviation of the left eye. His best-corrected visual acuity was 20/25 in the right eye and 6/12 in the left eye with limitation of motion of -4 at adduction in the left eye. Brain magnetic resonance imaging scans revealed a 3.0 × 2.5 × 2.5 cm-sized cystic mass suspected as a mucocele or nasolacrimal duct cyst invading the orbital space. The cyst was removed using a Lynch and caruncle incision, and intracystic fluid was aspirated. During the excision, a small defect of the skull base was detected with cerebrospinal fluid (CSF) leakage and leaking point of dura was sealed. His pathologic result was disorganized glial and fibrous tissue, consistent with encephalocele. Three days later, CSF leakage recurred. On postoperative day 8, duroplasty was performed. A one month later, his best-corrected visual acuity was 6/12 in the left eye with orthotropic eye position. Limitation of motion was improved to -1 at adduction with enophthalmos. No other complications were detected. @*Conclusions@#Congenital naso-orbital encephalocele invading the orbit is rare. However, a cystic mass in the sinuses involving the orbit should be considered, rendering thorough physical and radiologic examinations including computed tomography scans necessary to look for bone defects.