Ans) a (Orbital emphysema) Ref Dhingra 5th ed p431Orbital hemorrhage is a major complication of sinus surgery.Orbital emphysema is not mentioned in text books. All the other three are compli-cations of sinus surgery. Anterior epistaxisPosterior epistaxisIncidenceMore commonLess commonSiteMostly from Uutes area or anterior pan of lateral wallPosierosupenor pan of nasal cavity ; often difficult to localise the site of bleeding pointAgeChildren or young adultsAfter 40 yrs of ageCauseMostly traumaSpontaneous; ofteb due to hypertension orBleedingUsually mild, can be controlled by local pressure or anterior packBleeding is severe, requires hospitalisation; postnasal pack often requitedNeural structures, including the optic nerve or any structures running through the cavernous sinus, may be damaged during surgery. Cranial nerves that control extraocular movements (ie. CN III, IV, VI) are at risk, as are the ophthalmic (ie, VI) and maxillary (ie, V2) branches of CN V. Cerebrospi-nal fluid leak is possible if the roof of the sphenoid is violated.Intraoperative complications are predominantly vascular in nature and include persistent hemorrhage from the carotid artery or, infrequently, the cavernous sinus. Retrobulbar hemorrhage with proptosis and visual compromise requires urgent ophthalmological consultation and lateral canthotomy. Persistent hemorrhage from the sphenoid or cavernous sinus may require angiography to localize and control bleeding.Postoperative complications may be nasal, neurologic, or vascular in nature. Long-term complications include cosmetic deformities; septal per-forations may occur and are predominantly related to approach. In the perioperative state, epistaxis is also a risk. Hemorrhage from the internal carotid artery or cavernous sinus is a devastating complication that may occur intraoperatively or postoperatively. Immediately evaluate any unex-plained mental status changes or excessive bleeding.