The Spheno-Ostio-Choanal Polyp

Abstract

S phenochoanal polyps originate from within the sphenoid sinus and extend into the choana.There are a few descriptions in the literature of an isolated choanal polyp arising from the external face of the sphenoid. These spheno-ostio-choanal polyps occur in the setting of an otherwise normal sphenoid sinus; they are a curious entity.Choanal polyps represent only approximately 4% to 6% of all nasal polyps. 1 Most commonly, these large solitary polyps arise from the antrum of the maxillary sinus and are referred to as antrochoanal polyps; however, more rare variants of choanal polyps include those that arise from within the sphenoid and ethmoid sinuses. A sphenochoanal polyp originates from within the sphenoid sinus and extends through the ostium into the choana; polyps arising from the mucosa adjacent to the sphenoid ostium externally also have been described. 2 These polyps, which occur in the setting of an otherwise normal sphenoid sinus and are more aptly termed spheno-ostio-choanal, are an exceedingly rare and curious entity. We describe the first report, to our knowledge, of isolated, bilateral spheno-ostiochoanal polyps causing nasal obstruction. We obtained approval from the institutional review board of the Saint Louis University School of Medicine. REPORT OF A CASEAn 80-year-old man presented with severe, long-standing bilateral nasal obstruction no longer responsive to medical treatment. He reported no constitutional symptoms. His medical history was significant for hypertension, coronary artery disease, and prostatectomy. Nasal endoscopy revealed a large mucosa-coveredmassobstructingbothchoanae. Findings from the remainder of the ex-amination were normal. Computed tomographic imaging revealed a large mass filling the nasopharynx. Close review suggested the presence of 2 distinct masses, each emanating from the sphenoid region on either side. Nobonydestructionwasnoted;allthesinuses (including maxillary and sphenoid) were completely normal.The patient was prepared for a surgical procedure. During the operation, a large pedunculatedpolypattachedtothesphenoid faceadjacenttotheostiumwithinthesphenoethmoid recess was discovered on both sides (Figure). The masses were resected endoscopically via a transnasal, paraseptal approach. There were no complications; the patient was discharged home. The final pathology report was consistent with benign inflammatory polyp for left-side and rightside specimens. The patient had complete resolution of his obstruction and recovered well, with no endoscopic evidence of recurrence 13 months after the operation. COMMENTPatients with choanal polyps typically present with symptoms of nasal obstruction; purulent discharge, headache, and visual changes can also occur. 2 Because antrochoanal and sphenochoanal polyps can extrude into the nasal cavity, it may be difficult to distinguish the 2 entities on routine examination. Thus, computed tomography or magnetic resonance imaging is essential. An opacified sphenoid sinus combined with a clear maxillary sinus on imaging suggests that a...