The study report was conducted on the 30 year old male patient, underwent a fronto-ethmoido-maxillo-sphenoidal endoscopic sinus surgery using the navigation system. After the surgery, patient's right eye was noticed to have a swelling, a bruise, accompanied with the loss of vision of the right eye. Patient was then operated to decompress the orbit within an hour later. The eye was then reported to become less swollen and ocular motor was recovered
however, there was still no progress in visual acuity. CT scanner and magnetic resonance image only showed an orbital hematoma. Optic nerve and medial rectus muscle were pressed but not disrupted. The patient was transferred to ophthalmologists to do a funduscopy and a retinal angiography. Results con clued that vision loss was due to the occlusion of the right central retinal artery.