{
  "abstract": "A man in his early 20s presented with an 8-month history of unilateral nasal obstruction, hyposmia and thick nasal discharge, unresponsive to topical therapy. Preoperative CT demonstrated a smooth polypoidal mass occupying the left nasal cavity and extending into the postnasal space, most consistent with a choanal polyp of presumed maxillary origin. Endoscopic sinus surgery revealed a pedicle at the sphenoid ostium, with an otherwise clear sphenoid sinus, confirming a sphenochoanal polyp. This was unusual because preoperative CT showed only minimal mucosal change in the sphenoid sinus, a finding that typically argues against a sphenochoanal origin. The lesion was excised endoscopically at its site of attachment. Histopathology showed inflammatory nasal polyp tissue without granulomata, vasculitis or atypia. This case illustrates a diagnostic pitfall in which sphenochoanal polyps may mimic antrochoanal polyps on imaging; intraoperative identification of the true sinus of origin is essential to guide appropriate surgery and minimise recurrence.",
  "authors": [
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, UK"
      ],
      "name": "Anna Onderková"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, UK"
      ],
      "name": "Marlene Maria Speth"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, UK"
      ],
      "name": "Hesham A Saleh"
    }
  ],
  "title": "Sphenochoanal polyp arising from the sphenoid ostium and mimicking an antrochoanal polyp on preoperative imaging",
  "uid": "d6c65c5f-07d3-55c7-b1f9-b9241d4f722c"
}