Petergopalatine Fossa A Key Area In Rhinocerebral Mucormycosis Extension

Rhinocerebral mucormycosis is a rapidly progressive fungal infection that spreads from nose and sinuses to brain in short time. Cunent hypothesis about brain involvement explains that infection initiates in nose and progresses into orbit through ethmoidat sinuses via erosion of lamina papyranea. Then infection spreads from orbit apex to cavernous sinus and brain. Therefore, in addition to medical therapy surgical debridement of the sinuses plays a major role in treatment of these patients. The aim of this study is introduction of a new point of view about extension of mucor from the nose to orbit and brain. Also we discuss clinical implication of this perspective on surgery. Since 1997-2002 nine patients with mucormycosis involving nose. Sinuses and orbit were admitted in ENT ward of Imam Khomeini general hospital. 8 patients with positive pathology entered the study. Variable such as age, underlying diseases, symptoms, site of involvement, extent of debridement and its times, and outcome were studied. After review of the history, surgical reports and pathological results, we found these findings in almost all patients: 1) facial pain, facial anesthesia, paralysis of buccal branch of facial nerve, paralysis of extrocular muscles, chemosis, periorbital edema 2) involvement of cheek subcutaneous tissue, buccal fat pad, IOF, SOF, orbital apex, infraorbital and maxillary nerves 3) involvement of pterygoid fossa with or without infratemporal fossa extension. Three patients have survived. Causes of death in other five patients were pneumonia, hypokalemia, and arrythmis during anesthesia. Mucormycosis was under control in most of these patients. Pterygopalatine fossa is the main source for replication and extension of mucor. After entrance to the nose, mucor reaches this site and after involvement of IOF and SOF rapidly extends to retrobulbar portion of the orbit. Paranasal sinuses, buccal space, cheek, palate and infratemporal fossa may be secondarily involved. Exploration and debridment of this area has beneficial effect on surviving of these patients.