Introduction: In the diagnosis of chronic rhinosinusitis (CRS), computed tomography (CT) of the nose and paranasal sinuses (PNS) remains the gold standard investigation. Though the diagnostic nasal endoscopy (DNE) is an equally effective and easily available investigation for diagnosis of CRS, its reliability and clinical significance to that of patient's symptoms have to be proven.

Objective: The purpose of this study is to determine the correlations between the symptom severity score, radiological score, and the endoscopic score in the diagnosis of CRS. Methods: This prospective observational study included 70 patients with CRS. It was conducted in a tertiary care institute from January 2019 to June 2020. All patients were subjected to DNE and CT nose and PNS. Symptom score was assessed using Visual Analogue Scale (VAS) score of 0-10. DNE and CT scores were calculated using the Lund-Kennedy endoscopic scoring system and the Lund-Mackay CT scoring system, respectively. The correlation between these scores were done using Pearson's correlation coefficient (p-value).

Results: The mean and standard deviation of the symptom score by VAS was 7 ± 1.7; the Lund-Kennedy score was 7.6 ± 2.3, and the Lund-Mackay score was 14.3 ± 6.5, respectively. The symptom score had moderate correlation with the Lund-Kennedy Score (r = 0.643, p < 0.001) and high degree of correlation with the Lund-Mackay Score (r = 0.835, p < 0.001). The Lund-Kennedy score had a positive correlation with The Lund-Mackay score.

Conclusion: DNE can be utilized as an early diagnostic tool in the clinical evaluation of CRS and is equally effective as CT in diagnosing the same. At the same time, a CT scan can be done in patients with positive symptoms and can be reserved as a second-level investigation for those patients with negative endoscopic findings but who become symptomatic on follow-up.