Validation of a method for quantifying carotid artery calcification from panoramic radiographs

Carotid artery calcification can be visualized on panoramic radiographs. Incidental observation of these calcifications could identify patients in need of further screening. The purpose of this study was to validate the assessment and quantification of calcification on panoramic radiographs with the stenosis and the calculated resistive index (RI) from Doppler ultrasonography.Digital panoramic radiographs were used to assess the area of carotid artery calcification using tools available in NIH's ImageJ. Inpatient and outpatient discharge records were reviewed to identify subjects with a completed carotid Doppler ultrasound exam (n = 122).The quantification of carotid artery calcification was found to correlate well with the degree of stenosis (area under the curve [AUC] 0.81 [95% confidence interval [CI] 0.64, 0.98]) and the RI of the common carotid artery (AUC 0.79 [95% CI 0.59, 0.98]).This method for quantification of carotid artery calcification could identify patients in need of further evaluation.