Reliability of computed tomography scans in the diagnosis of chronic rhinosinusitis

Paranasal computed tomography (CT) has become the investigation method of choice to confirm or exclude the diagnosis of chronic rhinosinusitis (CRS) on the basis of its ability to deliver objective data regarding the presence of inflamed mucosa or polyps.

The aim of the study was to assess the reliability of CT scan findings among untreated CRS patients without the presence of polyps in a nasal endoscopy.

Among patients with clinically demonstrated CRS considered for surgery, 93 subjects who had had 2 CT scans performed at different time points in the diagnostic process were enrolled into the study. Paranasal sinus involvement on both CT scans was scored using the Lund-Mackay (L-M) and modified Lund-Mackay scales. Both CT exams served to assess the extent of the potential endoscopic sinus surgery.

The time interval between CT scans ranged from 31 to 1,162 days (mean: 338 days). The L-M scores from the 1st CT examination correlated statistically with the results of the 2nd CT (r = 0.86; p < 0.05). When compared to the 1st scan, the L-M score in the 2nd CT scan remained the same in 36 patients (39%), increased in 23 patients (25%) and decreased in 34 patients (36%). There was no statistically significant correlation between the change in the L-M scores and the time interval between CT examinations.

The present study indicates that mucosal thickening within paranasal sinuses among untreated patients with CRS is stable over shortand middle-time intervals, regardless of the initial intensity of the disease. The time delay between the CT examination and qualification for surgery does not influence the decision regarding the performance of the operation. The results suggest the conclusion that repeating CT scans in symptomatic, untreated patients with CRS should be seriously considered.