2025 Proffered Presentations
S222: ISOLATED SPHENOID SINUSITIS: FREQUENCY OF SKULL BASE EROSION AND ASSOCIATED COMPLICATIONS
Maria Catalina Espinosa, MD1; Sanjena Venkatesh, BA2; Alison Yu, MD1; Jennifer Douglas, MD1; Nithin Adappa, MD1; Michael Kohanski, MD, PhD1; 1Department of Otorhinolaryngology- Head and Neck Surgery, University of Pennsylvania; 2Perelman School of Medicine at the University of Pennsylvania
Background: Isolated sphenoid sinusitis (ISS) is uncommon, accounting for less than 3% of all paranasal sinus infections. Though typically benign, complications of ISS involving the skull base can be severe and life-threatening, necessitating a high degree of suspicion and prompt intervention. This study evaluates the incidence of skull base erosion and the variety of skull base complications in patients diagnosed with ISS.
Methods: We performed a retrospective chart review of 3,898 patients who underwent endoscopic sinus surgery from November 2010 to June 2024 at a single tertiary care institution. Of these, we identified 25 patients with a documented history of ISS. Patient demographics, clinical presentation, radiographic findings, sphenoid sinus pathology, intraoperative interventions, and postoperative outcomes were analyzed. Patients with a history of paranasal sinus opacification outside of the sphenoid sinuses were excluded.
Results: Seven of the 23 patients with a documented history of ISS who underwent endoscopic sinus surgery were found to have radiographic and intraoperative confirmation of skull base erosion (30%). Of these seven patients, three also had intracranial complications requiring a prolonged hospital stay (42%). The most common clinical presentation was headaches (61%), followed by facial pain (17%) and facial paresthesia (8.7%). Fungal elements were the most commonly identified organism on pathology (35%), with one case of invasive fungal rhinosinusitis presenting in the background of allergic fungal sinusitis. The most severe intracranial complications from ISS included temporal lobe abscess, cerebritis, pontine infarcts, subdural empyema, cavernous sinus inflammation, and infratemporal fossa inflammation. One patient developed a continuous sphenoid abscess extending to the posterior fossa and the retropharynx, resulting in a retropharyngeal abscess. All patients underwent endoscopic sinus surgery, and intracranial complications were managed with intravenous antibiotics without the need for intracranial procedures.
Conclusion: Although ISS is rare, it has the potential to cause significant skull base erosion and serious intracranial complications if not addressed promptly. Skull base erosion in the context of ISS warrants stronger criteria for intervention. Endoscopic sphenoidotomy, coupled with intravenous antibiotics, is an effective treatment modality and should be performed urgently in cases presenting with ISS complications.