"Black turbinate sign": a potential predictor of mucormycosis in cavernous sinus thrombophlebitis.

1 Fellow in Neuroradiology, Santa Casa de Misericórdia de São Paulo, São Paulo SP, Brazil; 2 Section of Neuroradiology, Santa Casa de Misericórdia de São Paulo, São Paulo SP, Brazil. Correspondence: Antônio José da Rocha; Rua Cincinato Braga 232; 01333-910 São Paulo SP Brasil Conflict of interest: There is no conflict to interest to declare. Received 24 August 2011; Received in final form 15 September 2011; Accepted 23 September 2011 Rhinosinusitis has the potential to result in catastrophic intracranial extension in the presence of predisposing conditions, such as diabetes, immunosuppression (fungus) or the incomplete treatment of bacterial infection. It is assumed that cavernous sinus thrombophlebitis (CST) is secondary to retrograde extension due to a valveless system of the vein that communicates paranasal cavities to the cavernous sinus1. The “black turbinate sign” results from dry gangrene in affected Figure. Mucormycosis exhibiting “black turbinate sign” that is characterized by low signal intensity (large arrow) of the right inferior nasal turbinate on the coronal T2 image (A) and the absence of enhancement (large arrows) after intravenous gadolinium administration on coronal (B) and axial (C) T1 images; note the typical ipsilateral CST (small arrows). The lack of these features can be observed in the comparative images of bacterial rhinosinusitis associated with bilateral CST (arrows in D-F). Both patients had additional orbital compromise. A B C F E D