A comparative study of 2 imaging techniques for the diagnosis of condylar fractures in children

Abstract

Purpose: We sought to compare the sensitivity and specificity of panoramic radiographs with those of coronal computed tomography (CT) scans in the diagnosis of mandibular condylar fractures in the pediatric population.

Methods: Medical, dental, and radiographic records of patients who presented between 1995 and 2000 were evaluated for injuries involving the mandibular condyle. The sample included 22 males and 15 females with ages ranging from 2 to 15 years (mean, 8 years). Control subjects were added and matched by age and gender. The panoramic radiographs were blocked to allow separate evaluation of each condyle. Representative images from the CT scans were selected and individually photographed for projection. Both sets of images were evaluated by 4 groups of examiners: oral and maxillofacial (OMF) surgeons who regularly deal with pediatric trauma (n = 2), community OMF surgeons who had been out of training for at least 5 years (n = 6), OMF radiologists (n = 3), and OMF surgery residents (n = 6). Each image was shown for 20 seconds and the examiners were given 3 options to choose: 1) fracture, 2) no fracture, and 3) uncertain.

Results: The overall diagnostic accuracy of CT scanning was 90% (sensitivity, 92%; specificity, 87%), and that of panoramic radiographs was 73% (sensitivity, 70%; specificity, 77%). Of interest, the most experienced clinicians were also those most likely to respond that panoramic films were not diagnostic. Statistical analysis of the results was performed using chi(2) analysis. The differences for sensitivity measurements using the CT scan were not statistically significant (P >.1). However, the differences in sensitivity measurements using the panoramic radiographs and the specificity measurements using both the CT and panoramic radiographs were statistically significant (P <.05).

Conclusions: CT scans provide consistently greater accuracy of diagnosis, sensitivity, and specificity than panoramic radiographs in the assessment of children suspected of having condylar fractures. In view of the high rate of false-negative and false-positive results associated with panoramic radiographs, coronal CT scans should be considered routine investigation in these patients.