Inflammation of the walls of the external auditory canal is referred to as otitis externa. This condition, also commonly known as swimmer's ear, is characterized by symptoms such as itching, redness, and discomfort in the ear canal. The inflammation can be caused by bacterial or fungal infections, often resulting from moisture retention or irritation.
When considering the other options, otitis media refers to inflammation of the middle ear, which is a different anatomical area and typically involves symptoms like ear pain and hearing loss related to middle ear congestion. Impacted cerumen pertains to a blockage in the ear canal caused by earwax buildup, which can lead to discomfort and hearing issues but does not involve inflammation of the canal walls. A prolapsed canal describes a condition where the ear canal's structure becomes abnormal or displaces, but it does not specifically address inflammation.
Therefore, otitis externa is the appropriate term to describe the inflammation within the external auditory canal accurately.