INTRODUCTION

This study investigated the differentiation of radicular cysts from granulomas. Cone beam computed tomography (CBCT) imaging was compared with the existing standard, biopsy and histopathology.

METHODS

Forty-five patients scheduled for an apicoectomy received a CBCT scan of the involved arch. Two oral and maxillofacial radiologists, working independently and using the same criteria, categorized the CBCT images as one of the following: cyst, likely cyst, likely granuloma, granuloma, or other. After apicoectomies, two oral pathologists, working independently and using the same criteria, diagnosed the surgical specimens as one of the following: radicular cyst, granuloma, or other. We examined the following: (1) interrater agreement between pathologists as to the biopsy diagnosis, (2) interrater agreement between radiologists as to the CBCT diagnosis, and (3) accuracy of radiologists' diagnostic assessments using histopathology as the standard.

RESULTS

Findings showed strong interrater reliability between pathologists (kappa=0.79, z=5.46, p<0.0001) and weak interrater reliability between radiologists (kappa=0.14, p=not significant). Accuracy (true-positives plus true-negatives) for the two radiologists was 51% and 63%.

CONCLUSION

Under the conditions of this study, based on the inconsistency of the radiologists' reports as evidenced by statistical analyses, it was concluded that CBCT imaging is not a reliable diagnostic method for differentiating radicular cysts from granulomas. Surgical biopsy and histopathological evaluation remain the standard procedure for differentiating radicular cysts from granulomas.