CONCLUSIONS
To our knowledge this is the first literature review specifically focussing on PNN and our review encompassed the entire history of the procedure back to 1997. We undertook a robust search which yielded enough studies to undertake a meaningful evaluation of the procedure to date in patients with both allergic and non-allergic rhinitis.
PNN is a safe procedure with a low risk of complications. The available literature suggests it is effective in controlling symptoms and all studies but one reported significant symptomatic improvement following PNN with or without other procedures. The procedure should be considered in rhinitic patients with a high symptom burden inspite of maximal medical therapy. However, there is a need for high quality, adequately powered, randomised controlled trials with longer follow-up periods comparing patient-reported outcomes after PNN to medical therapy.