Incidental Findings in Small Field of View Cone-beam Computed Tomography Scans

The use of cone-beam computed tomography (CBCT) in endodontics has increased in recent years. In clinical application of small field of view (FOV) CBCTs, these scans are not reviewed routinely by a radiologist. Studies of large FOV CBCT scans show the prevalence of incidental findings to be greater than 90%. The purpose of this study was to evaluate the prevalence of missed findings by endodontic residents as compared with a radiologist on small FOV CBCT scans.

Two hundred three small FOV CBCTs obtained for endodontic purposes were analyzed by an endodontic resident and a medical radiologist. The reported findings of each practitioner were compared to evaluate for missed incidental findings by the endodontic resident.

The radiologist reported abnormalities in 176 of the 203 subjects (87%), with a total of 310 abnormalities reported. The endodontic resident reported abnormalities in 102 of the 203 subjects (50%), with a total of 126 abnormalities reported. The percentage of scans with any abnormality reported by the radiologist was significantly greater than the endodontic resident (P < .001). There was no significant difference between jaw locations in percentage of missed findings for the 3 most common types of finding-rarefying osteitis, sinusitis/mucosal lining thickening, and excess restorative material in the periapical area. Rarefying osteitis was missed significantly less than the other 2 types of findings (P < .001).

A radiologist is significantly more likely to identify incidental findings in small FOV CBCT scans than an endodontic resident. Scan location had no significant association with the rate of missed findings.