A simple way of predicting which patients will require revision endoscopic surgery does not yet exist. This study, which is a prospective, longitudinal cohort study, part of the UK national audit, aims to predict this by using a relatively simple, available tool: the SNOT-22. The study looks at the value of a minimal important clinical difference (MCID) – an improvement in symptom score by nine points. Several factors have already been shown to raise the risk of revision surgery, such as initial high scoring CT, incomplete sinus dissection, asthma, aspirin sensitivity, predominant Th2 type inflammation and high eosinophilia. Six hundred and sixty-eight patients were divided into two groups depending on their response to surgery. The first group had an improvement in SNOT-22 scores post-surgery equal to at least one MCID. The second had a deterioration in SNOT-22 by one MCID between 3 and 12 months. Mean revision rate for the entire group was 8.5% at 60 months. At three months 70% of patients reported an improvement in SNOT-22 at least equal to an MCID. Patients were followed at 3, 12, 36 and 60 months and at each point there was a decline in the percentage reporting an MCID improvement.
In the end at 60 months, 57.5% were still one MCID over baseline. There was a statistically significant association between failing to maintain an MCID improvement at 3, 12 and 36 months and the need for revision surgery. Patients who deteriorated by one MCID between 3 and 12 months were also found to be significantly at risk for revision surgery.
This study demonstrates that using the SNOT-22 for 12 months post sinus surgery can help to determine the cohort that may require revision surgery in the future.
