Identification of Tonsilolliths in CBCT and Panoramic Images

Method: It was selected 100 patients who had both panoramic  and CBCT exams performed to implant planning. The exam dates were not over one year apart from each other. The patient age varied from 19-77 years (mean 48 years). All analyses were done blindly and the panoramic images were analyzed first. To achieve an intraobserver agreement the analyses were repeated one month later. To better delimitate the region of the thonsills the observer draw a line from styloid to the hyoid bone in CBCT images, therefore it was possible to exclude possible small partial ossifications of the styloid complex (SC).

Result: The intraobserver agreement was excellent to good (Kappa/0.7). Regarding the panoramic images, it was found 25 tonsilolliths (17 left side/8 right side) in 18 patients. Regarding the correspondents CBCT exams, it was found 61 tonsilolliths (40 left side/21 right side) in 27 patients. There was not statistically significant difference between sex and presence of tonsilolliths for either exam (Spearman/p>0.05). There was a statistically significant difference between CBCT and panoramic images regarding the tonsilolliths presence (Wilcoxon/p<0.05) for both sides. Considering left/right sides (200) it was found that the panoramic exams were false-negative in 31(15.5%) sides, false-positive in 9(4.5%) sides and coincidental with CBCT in 160(80%) sides.

Conclusion: The importance of tonsilolliths identification is mainly due to the differential diagnosis with other neck calcifications as styloid complex and Eagle Syndrome diagnoses. In order to discriminate both is necessary to determine in the CBCT image the SC trajectory so that exclude possible mistakes between small styloid complex ossification and tonsilolliths. In the overall, we could say that despite its focal layer limitations the panoramic images performed well in the tonsilollith identification showing a false-negative tendency.