Versatility of high resolution ultrasonography in the assessment of granulomas and radicular cysts: a comparative in vivo study.

Objectives: To evaluate and compare the diagnostic potential of high resolution ultrasound with periapical radiographs (PR) and CBCT in assessing granulomas and radicular cysts.

Methods: This study included a total of 33 teeth from 33 patients with periapical lesions. Subjects were distributed among three groups. A consisted of teeth that were extracted. B consisted of teeth treated with root-canal treatment followed by apical surgery. C consisted of teeth treated with root-canal treatment only. Pre-treatment PR, ultrasound and CBCT images were obtained for Groups A, B and C and 6 month post-treatment PR and ultrasound images were obtained for Groups B and C. In addition, histopathological analysis was performed on lesions in Groups A and B. Lesions were classified as either cystic lesions or granulomas. Width, height, depth, surface area and volume of lesions were measured using the built-in softwares of the appropriate imaging modalities. Measurements were compared by Wilcoxon and paired sample t tests. Ultrasound and histopathological findings were compared with κ and Mc Nemar. Statistical significance was set at < 0.05.

Results: κ coefficient (0.667; = 0.002) suggested good agreement between ultrasound and histopathology. No statistically significant differences were found among periapical radiography, CBCT and ultrasound in the pre-treatment measurements of lesion width ( = 0.308) or between CBCT and periapical radiography in the pre-treatment measurements of lesion height ( = 0.863). In all cases, mean measurement values for all variables were lower for ultrasound than for CBCT.

Conclusion: Ultrasound provided useful information for the diagnosis and assessment of granulomas and radicular cysts.