Synthesis Without Meta-analysis of Empty Nose Treatments: Is There Evidence that Empty Nose Syndrome Treatments Are Effective?

Empty nose syndrome (ENS) is a rare complication following nasal surgery, particularly surgery of the turbinates, with limited effectiveness of its treatments. A synthesis without meta-analysis (SWiM) was carried out to assess treatments and their reported effectiveness. In August 2022, a literature search was conducted on PubMed, Google Scholar, Cochrane Database, Science Direct, and Embase. Article selection, eligibility assessment, and risk of bias evaluation of each article were performed independently by each author and then compared. A synthesis without meta-analysis was then conducted on the selected studies. Forty-three articles were selected from 445 potential references, encompassing 586 patients. The quality of publications on ENS was generally poor or critical. Reported treatments for ENS, attributed to a combination of endonasal aerodynamic changes, impaired intranasal trigeminal function, and psychological factors, primarily consisted of intranasal topical instillations, lower meatus filling, stem cell therapy, and psychological/psychiatric management. However, all reported case series were subject to significant biases. As it was not feasible to address the question, "How effective are the treatments for ENS?" this synthesis aimed to answer, "Is there evidence of effectiveness of ENS treatments?" Possible treatments encompassed medical, surgical, psychological, and respiratory interventions. Nevertheless, the available data with limited bias were insufficient to provide precise recommendations for their indications. Future research employing robust methodological approaches is essential to assess treatment effectiveness. Keywords: Empty nose syndrome, treatment, synthesis without meta-analysis