Objectives:: Approximately 7% of patients examined with panoramic radiographs (PRs) for odontological reasons, and with incidental findings of carotid artery calcification (CAC), have significant (≥50%) carotid stenosis (SCS). The aim of this study was to determine if the radiographic appearance of CACs in PRs could be categorized such that we could improve the positive-predictive value (PPV) for SCS detection.
Methods:: This cross-sectional study included 278 patients with CACs identified by PRs, 127 with SCS and 151 without SCS. CACs were categorized based on the following appearances: (1) single, (2) scattered or (3) vessel-outlining. Correlates were derived for each category according to positivity or not for SCS in the corresponding neck sides. For a representative adult population (in dentistry) presenting with CACs in PRs, PPVs for SCS prediction were then calculated for three subgroups based on different combinations of appearances (2) and/or (3).
Results:: Vessel-outlining CACs corresponded to 65% of neck sides with SCS vs 47% without SCS (p < 0.001). Single CACs corresponded to 15% of neck sides with SCS vs 27% without SCS (p = 0.006). Scattered CACs corresponded to 20% of neck sides with SCS vs 26% without SCS (p = 0.127). In the representative population, the PPVs for SCS detection were comparable (7.2-7.8%) for all three subgroups and when the presence of a CAC is the sole criterion (7.4%).
Conclusions:: Stratifying the radiographic appearance of CACs in PRs does not improve the PPV for SCS detection. Whether different radiographic appearances are associated with future risk of stroke, or other cardiovascular events, remains unknown.
Keywords: calcification; carotid stenosis; panoramic radiography.