The Black Turbinate Sign, A Potential Diagnostic Pitfall: Evaluation of the Normal Enhancement Patterns of the Nasal Turbinates.

A black turbinate is not uncommon on MR images in immunocompetent patients who have no chance of having invasive fungal rhinosinusitis. Benign turbinate nonenhancement improves over subsequent series, has preserved thin peripheral enhancement, and often has thin internal septa. Knowledge of this normal pattern of nasal turbinate enhancement can aid in the differentiation of the benign black turbinate in immunocompetent patients from the pathologic black turbinate seen in patients with invasive fungal rhinosinusitis.