Objectives:  Mucosal changes in the paranasal sinuses are detected in 30–50% of scans for non‐rhinological disease. This study assesses the relationship between symptoms of rhinosinusitis and radiological evidence of sinus pathology in patients undergoing magnetic resonance imaging (MRI) scans for unrelated pathology.

Design:  Prospective observational study, evaluating symptoms of rhinosinusitis in patients undergoing MRI scanning of the internal acoustic meati. A visual analogue scale (VAS) of rhinological symptoms was completed immediately before scanning, specifying symptoms present at the time of completing the questionnaire. Symptom scores were recorded by one of the investigators, blinded to the MRI images. Two investigators independently rated sinus mucosal thickening for each scan, both of whom were blinded to the symptom scores. Lund and Mackay scoring systems were used for both symptom and radiological scores, which were then compared.

Setting:  Otolaryngology and Radiology Departments in a large teaching hospital.

Participants:  Fifty consecutive patients were recruited over a 2‐month period.

Main outcome measures:  Visual analogue scale symptom scores were compared with radiological scores for sinus mucosal thickening.

Results:  No statistically significant relationship was demonstrated between rhinological symptoms and radiological features suggestive of rhinosinusitis in patients undergoing MRI scanning for non‐rhinological disease.

Conclusions:  The relationship between rhinological symptoms and MRI findings of sinus pathology is not straightforward. Management decisions should be made on the basis of nasal history and endoscopy, rather than radiological findings. This is the first study assessing this relationship by documenting symptoms on the day of scanning, using a validated scoring system.