Question: Why do we dilate eyes with internal inflammation?

Answer: When the iris becomes inflammed, such as from trauma, uveitis, or infection, it becomes “sticky” and likes to adhere to nearby structures. The iris can stick down to the underlying lens which can become a problem if 360 degrees as this creates an iris bombe glaucoma. it can also adhere to the cornea at the limbus, which can in turn affect aqueous outflow through the angle.

A cycloplegic can make the patient more comfortable, as this will paralyze the iris/ciliary body and keep them from spasming with bright lights. Also, a short or medium acting cycloplegic can help keep the iris moving, so that it doesn’t form synechae or breaks the ones that are forming to nearby structures.