The Relation Between the Lower Lateral Cartilages and the Function of the External Nasal Valve.

INTRODUCTION: The position of the lower lateral cartilages (LLC) is closely related to the function of the external nasal valve (ENV). When there is a cephalic malposition of these cartilages, the nasal alae have inadequate support, which leads to ENV insufficiency during deep inspiration.

METHODS: Retrospective study with 60 patients evaluated: the positioning of the LLC and the occurrence of ENV insufficiency; the effectiveness of structuring the medial and lateral walls of the ENV; and the frequency of the grafts used for structuring it.

RESULTS: Of the 60 operated cases, 37 patients (62%) had ENV insufficiency, in 23 cases there was cephalic malposition of the LLC, and in the latter group 17 patients (74%) presented this insufficiency. A structured ENV was effective in the treatment of this insufficiency (p = 0.001). A lateral crural strut graft was performed in 24 cases (40%) of 60 patients operated. The alar contour graft was performed from 2013 to 2015 in 4 patients (22%) of 18 cases operated, and between 2016 and 2018 it was performed in 29 patients (69%) out of 42 cases. The columellar strut was routinely used from 2013 to mid-2016 in 33 cases (100%), and after that period until the present day the tongue-in-groove technique was performed in 11 cases (41%) and in the remaining 16 cases (59%) the caudal septal extension graft was performed.

CONCLUSION: Cephalic malposition of the LLC is an important red flag of ENV insufficiency. This insufficiency should be treated by structuring the walls of the ENV.

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