Septal perforation (Figure 1 and Figure 2) has not been seen as a background lesion. It typically occurs after exposure to highly irritating agents that cause necrosis and ulceration of the mucosa and atrophy of the nasal turbinates. Therefore, it is typically preceded or accompanied by epithelial lesions, such as squamous metaplasia, ulceration or necrosis, inflammation, and turbinate atrophy. It is most commonly seen in chronic inhalation studies.
Septal perforation should be diagnosed whenever present but need not be graded. Other lesions, including epithelial lesions (degeneration, necrosis, ulceration, squamous metaplasia, etc.), turbinate atrophy, and inflammation, should be diagnosed separately.