ENT Case 8. Sinonasal endoscopic surgery from a diabetic patient.

Diagnosis: invasive fungal sinusitis

The findings can be subtle under microscope, with only small fragment of necrotic tissue:

High power:

Invasive fungal sinusitis is a fulminate medical emergency. Both false positive and false negative diagnosis have severe consequences. At frozen section, when not sure about the diagnosis, pathologists can ask for more tissue for microscopic examination.