A Sticky Situation

Question: A 45-year-old man presents to your clinic for persistent hearing loss after undergoing right-sided stapedectomy.  He notes that his hearing was unchanged immediately after surgery.  Audiogram reveals a low to mid frequency 40 dB conductive hearing loss with normal hearing on the contralateral side.  Tuning fork reveals bone conduction greater than air conduction on the right.  Word recognition is 100%.  On CT scan, there is no evidence of superior semicircular canal dehiscence, but there is an abnormality noted on coronal imaging. What is the most likely diagnosis?  

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

Answer to last week's question, Cavernous Take II (Feb 9, 2015):

Despite the fact that Mucor is more common in diabetic patients, overall the most common causative agent in invasive fungal sinusitis is Aspergillus.