Updating nasalisation: From concept to technique and results

Nasalisation is a surgical technique proposed for the treatment of nasal polyposis in 1995. The technique as initially described was based on large opening of the maxillary, sphenoidal and frontal ostia and resection of the middle turbinates, with the aim of resecting the mucosa of the lateral masses of the ethmoid as completely and safely as possible. Recent findings on the evolution and development of the nose and sinuses and sinus physiology allow both the concept and the technique of nasalisation to be updated. According to evo-devo theory, the ethmoid is not a paranasal sinus but the skull-base bone housing the olfactory mucosa. In humans, the olfactory mucosa can be distinguished as functional in the upper recess of both olfactory clefts and vestigial in the rest of the ethmoid bone. Nasal polyposis presents clinically as a specific disease of the vestigial olfactory mucosa of the human ethmoid (and not as a particular kind of chronic rhinosinusitis). The aim of surgery for nasal polyposis is thus maximal resection of the vestigial olfactory mucosa, conserving olfactory function as long as possible. By the production, storage and bolus release of nitric oxide thanks to the sphincter function of the paranasal (maxillary, sphenoidal and frontal) sinus ostia, the paranasal sinuses perform a respiratory function that should be conserved as much as possible. The nasalisation technique has been modified in order for the vestigial olfactory mucosa to be completely resected while sparing the sinus ostia. Middle turbinate surgery still needs to be evaluated: resection is a step toward maximal removal of vestigial olfactory mucosa, while conservation could ensure olfactory cleft integrity. Thus, updating the concept of nasalisation enables the nasalisation technique to be integrated in the evo-devo concept of rhinology.