The validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fractures.

The aims of this study were to determine the sensitivity, specificity, positive and negative predictive values of ultrasonography in detecting zygomaticomaxillary complex fractures, and to highlight factors that may affect the validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fracture. Twenty-one patients with suspected fractures of the zygomaticomaxillary complex presenting at the authors' hospital were included in this prospective study. All the patients had plain radiographic and computed tomography (CT) investigations. All underwent ultrasonographic examination of the affected region using an ultrasound machine with a 7.5 MHz probe. The different radiologists were not aware of the results of the other two investigations. Statistical significance was inferred at P<0.05. The validity of ultrasonography varied with fracture sites with a sensitivity of 100% for zygomatic arch fractures, 90% for infraorbital margin fractures and 25% for frontozygomatic suture separation. Specificity was 100% for the three types of fracture. There was no statistically significant difference in the ability of CT scan and ultrasonography to diagnose fractures from various zygomaticomaxillary complex fracture sites (P=0.47). Ultrasonography has proved to be a valid tool for the diagnosis of zygomatic arch and displaced infraorbital margin fractures.