3.1 NICE did a rapid review of the published literature on the efficacy and safety of this procedure. This comprised a comprehensive literature search and detailed review of the evidence from 7 sources, which was discussed by the committee. The evidence included 1 systematic review, 1 randomised controlled trial, 3 single-arm trials, 1 case-control study, and 1 analysis of the Food and Drug Administration's Manufacturer and User Facility Device Experience database. It is presented in the summary of key evidence section in the interventional procedures overview. Other relevant literature is in the appendix of the overview.
3.2 The professional experts and the committee considered the key efficacy outcomes to be: improvement in quality of life, need for repeat procedures and reduction in rhinitis symptoms.
3.3 The professional experts and the committee considered the key safety outcomes to be: bleeding, pain, dry eyes, nasal dryness and infection.
3.4 Patient commentary was sought but none was received.
3.5 In the evidence reviewed by the committee, there was no reduction in concomitant medication use. However, the committee was informed that this was not the primary intention of the procedure and that the procedure could help the medication to work more effectively.
3.6 In the evidence reviewed by the committee, most studies only reported follow-up data within 1 year. The short-term evidence showed improvements in rhinitis symptoms and quality of life. However, the evidence was limited and included people with different types of rhinitis. The committee was informed that cryotherapy might be more useful for treating non-allergic rhinitis than allergic rhinitis, because there are more treatments available for allergic rhinitis than non-allergic rhinitis. Further research is needed to better establish the efficacy of this procedure. In particular, research is needed on which group of patients will benefit most from the procedure and how long the effect of the treatment will last.
3.7 This procedure is typically done in conjunction with nasal endoscopy.