An Atypical Presentation of Chronic Invasive Fungal Rhinosinusitis with Skull Base Extension Treated Exclusively with Antifungal Therapy

Introduction: Invasive fungal rhinosinusitis (IFRS) is classified into acute, chronic, and granulomatous forms. Acute IFRS requires immediate widespread debridement as well as prolonged antifungal therapy, but the optimal treatment for the chronic and granulomatous invasive forms, including the degree of surgical intervention and type of antifungal therapy, is less well-defined. Most surgeons endorse a combination of surgical debridement and antifungal therapy to treat chronic and granulomatous disease. We discuss an atypical case of biopsy-proven chronic IFRS (CIFRS), with retroorbital and skull base extension that was successfully treated exclusively with a prolonged course of anti-fungal therapy.

Case Presentation: An 84 year old man had 8 months of right retro-orbital pain that progressed to right eye visual loss, oculomotor paralysis, and parasthesias of the right hemi face. Additionally, he experienced anorexia, general fatigue, and 20 pound weight loss. He had no active sinusitis symptoms, and he denied any history of sinus disease. His medical history was notable for prostate cancer treated in 2005 with radiation. Physical exam was notable for a loss of vision without light perception in the right eye, a right cranial nerve III palsy with complete ptosis, and decreased sensation in right V1 distribution. Ophthalmologic exam showed a pale right optic disk. The left eye was entirely normal. The patient was sent for head MRI (Fig. 1) and CT (Fig. 2), which demonstrated a mass involving the right orbital apex and cavernous sinus. Endoscopic biopsies of the sphenoid sinus and cavernous sinus surprisingly revealed CIFRS with Aspergillosis fumigatus. Given the morbidity of orbital and cavernous sinus exenteration in this elderly patient he was maintained on antifungal therapy, transitioning from intravenous to oral voriconazole. Periodic voriconazole troughs confirmed consistently therapeutic levels. His disease burden was closely monitored with serial MRI scans (Fig. 3). Four months after starting voriconazole, the mass began shrinking in size. After 13 months of treatment, the patient was doing very well. His appetite and energy level had improved significantly, his retro-orbital pain and oculomotor palsy resolved, but his visual loss remained. As of his most recent follow-up appointment two months after cessation of anti-fungal therapy, the patient's residual symptoms and the radiographic appearance of the mass remain unchanged.

Conclusion: This case illustrates CIFRS can develop in patients without underlying sinus disease or antecedent sinusitis, and should be considered in the differential diagnosis of patients presenting with isolated skull base lesions. This also adds to a growing literature demonstrating the sustained efficacy of exclusive second-generation antifungals in the medical treatment of extensive CIFRS not amenable to surgical intervention.