BACKGROUND [corrected] Aspergillosis of the paranasal sinuses is subdivided into noninvasive and invasive types, depending on invasion of the tissue. The invasive form often occurs in immunodeficient patients and can be divided further into granulomatous, chronic invasive, and acute fulminating forms. METHODS We report the clinical course of an immunosuppressed 64-year-old male with invasive aspergillosis originating from the sphenoid sinus with infiltration of the orbit and intracranial extension into the cavernous sinus. The patient was referred to our hospital with loss of vision, ptosis, and ophthalmoplegia of 3-month duration. Additionally he suffered from diabetes mellitus II and kidney failure after kidney transplantation. After CT scanning, endonasal sinus debridement and decompression of the orbit were carried out immediately. Histology revealed invasive aspergillosis. Postoperatively, both systemic and local antimycotic therapy and antibiotic treatment were performed. According to recommendations of the Undersea and Hyperbaric Medicine Society, cerebral abscess is a certain indication of hyperbaric oxygenation. We decided to attempt therapy for that as well. The patient died 3 weeks after surgical intervention due to carotid dissection. CONCLUSIONS Invasive aspergillosis of the paranasal sinuses and the skull base of immunsuppressed patients is usually lethal because of intracranial complications. Therefore, fast diagnosis using CT and MRI and surgical and antimycotic therapy are necessary.