The Third Nostril: Combining the Contralateral, Subtarsal, Transmaxillary Retro-Eustachian and Endoscopic Endonasal Approaches to the Jugular Foramen

Objectives: The eustachian tube (ET) limits the endoscopic endonasal access to the infrapetrous region. Removing the ET or lateralizing it during endoscopic endonasal approaches to the region of the ventral jugular foramen may result in conductive hearing loss or infections. A novel surgical strategy where a subtarsal contralateral transmaxillary (ST-CTM) approach is combined with the traditional endoscopic endonasal approach (EEA) (i.e., transpterygoid and inferior transclival) to facilitate access to the infrapetrous region in a retro-eustachian fashion without transecting or mobilizing the ET is explored.

Methods: Eight cadaveric head specimens were dissected. Endoscopic endonasal approaches (EEA) were performed on one side, followed by the ST-CTM and sublabial contralateral transmaxillary (SL-CTM) approaches on the opposite side, followed by different ET mobilization strategies on the initial side. The length of cranial nerves, areas of exposure, and volume of surgical freedom (VSF) in the jugular foramen region were measured and compared amongst seven groups.

Results: The third-nostril approach (combined EEA/ST-CTM approach) provided greater area of exposure than the EEA alone even when the ET was not mobilized (mean ± SD was 288.9 ± 40.66 mm² versus 91.70 ± 49.90 mm², respectively, p = 0.001). EEA/ST-CTM provided higher VSF than EEA alone when accessing the ventral jugular foramen (JF), entrance to the petrous internal carotid artery (ICA), and a point lateral to the parapharyngeal ICA (p = 0.002, p = 0.002, and p < 0.001, respectively). In contrast, EEA/ST-CTM provided less VSF at the hypoglossal canal (HGC) than EEA alone (p = 0.01). The area of exposure was not improved by the SL-CTM approach (p = 0.48). Better exposure via the EEA/ST-CTM approach was provided in comparison to EEA with extended inferolateral (EIL) or anterolateral (AL) ET mobilization (p = 0.001 and p = 0.02, respectively). EEA with EIL was inferior to the third nostril approach with regard to VSF at a point lateral to the parapharyngeal ICA (p < 0.001).

Conclusion: A novel approach, the third nostril approach, is evaluated. Through a standard subtarsal incision, the floor of the contralateral orbit is used to access the nasal cavity lateral and superior to the contralateral naris and in direct alignment with the infrapetrous region behind the ET. A better exposure of the region of the ventral JF was obtained while preserving the ET in its native location.

Publication History

Article published online:
01 February 2023