Question: A 62 year old woman presents with a headache, double vision, and nasal obstruction.  You obtain a maxillofacial CT scan and note a destructive mass which appears to originate from the left sphenoid sinus.  It appears to have invaded into the nasal cavity and through the lateral sphenoid bone and has just started to involve the cavernous sinus.  You take the patient to the operating room and biopsy an area of necrotic appearing tissue.  Your pathologist calls in to tell you they see fungal elements invading into the surrounding tissue and evidence of angioinvasion.  This patient is a poorly controlled diabetic.  What is the most likely etiologic agent?

[Answer will be posted with next week's new question]

Answer to last week's question, Cavernous Concerns (Feb 2, 2015):

Abducens palsy.  Cranial nerve VI is the most medial nerve within the cavernous sinus and is the first to be impacted from a process within the cavernous sinus arising from the sphenoid.  The patient would have a lateral gaze deficit in the involved eye and would likely complain of some diplopia.