Comparison of accuracy of computed tomography scan and ultrasonography in the diagnosis of mandibular fractures

Dent Res J (Isfahan). 2020 May 23;17(3):225-230. eCollection 2020 May-Jun.

Abstract

Introduction: Ultrasonography (USG) allows to the examination of soft tissue and osseous tissues in the head-and-neck region. This study compared the accuracy of USG and computed tomography (CT) scan in the diagnosis of mandibular fractures.

Materials and methods: In this prospective observational study, spiral CT scan was prescribed for the lower face and, if necessary, midface and upper face in 42 trauma patients suspected of mandibular fractures, referring to Imam Reza Hospital in Tabriz. Two radiologists evaluated the CT scans. Then, another radiologist examined all the patients with USG with a frequency of 7-12 MHz. Ultrasonographic diagnostic results were recorded and compared with the results of the CT scan examinations. The results were reported using descriptive statistical methods.

Results: The specificity and sensitivity of USG were 100% and 91.1%, respectively. The USG sensitivities in the angle, condyle, condylar neck, and symphysis fractures were 100%, 91.6%, 85.7%, and 80%, respectively, and the specificity was 100% in all that anatomical regions. Among the confounding factors, the sensitivity of the USG (84.6%) was the lowest in the presence of hematoma; however, its specificity remained 100%. One case of symphysis fracture was not detected in the absence of any confounding factors in USG examination.

Conclusion: Although the sensitivity, specificity, and diagnostic accuracy of the USG were at high levels, there were some limitations, making it difficult to definitively replace USG with CT scans, especially in the case of condylar fractures and in the presence of confounding factors such as hematoma and swelling.

Keywords: Computed tomography scan; mandibular fracture; sensitivity; specificity; ultrasonography.