Diagnosis and Treatment of an Infected Supraorbital Ethmoid Cell Cyst

1. Case Report A 79-year-old woman with no significant medical history visited an emergency room with a complaint of diplopia. Ocular motility disorder was noted, and a central lesion was suspected. Contrast-enhanced computed tomography (CT) revealed a cystic lesion, and cyst infection was suspected based on the rim enhancement. Coronal images (Figure 1) suggested a frontal sinus cyst, but horizontal (Figure 2) and sagittal (Figure 3) sections revealed a Supraorbital Ethmoid-Cell (SOEC) cyst extending into the orbit. Diplopia disappeared immediately after endoscopic surgery for cyst enucleation. Anatomically, SOECs are associated with the anterior ethmoidal artery (AEA), which runs within or in continuity with the posterior border of the SOEC opening [1] (Figure 4). Therefore, in endoscopic surgery, the risk of AEA damage increases with a posterior approach, and an approach from the front is recommended. If an axillary flap [2] is not created and the nasal ridge is not sufficiently excised, it is difficult to operate using an endoscope.