If epinephrine use is contraindicated, alternative approaches may be necessary. The CT of the sinuses should be evaluated closely for the course of the optic nerve and its relationship to the posterior ethmoid and the sphenoid sinuses. The size and shape of these sinuses are variable. The posterior ethmoid air cells can project above and around the sphenoid sinus. There is greater risk of close contact with the optic canal in this situation.
Visual acuity needs to be noted.
Draping of the patient should allow direct observation of the eyes. The lamina papyracea is very thin and is easily perforated. The presence of orbital fat needs to be quickly recognized. Injury to nearby vessels is possible and an orbital hematoma may develop. Prompt notice of this can help to avoid serious complications such as blindness.