Ultrasonographic evaluation of oral submucous fibrosis in habitual areca nut chewers.

[oral submucous fibrosis]

To characterize the sonographic features of the buccal mucosa in patients with oral submucous fibrosis (OSF ).Three groups (controls with areca-related habits , controls without areca-related habits and clinically diagnosed OSF cases ), each comprising 30 subjects , were included in the study . After a thorough clinical examination , transcutaneous B-mode ultrasonography was performed with a multifrequency linear transducer (5 -10 MHz ) for anterior and posterior buccal mucosa bilaterally . Both clinical and ultrasound findings were recorded by three independent observers . One -way analysis of variance and Tukey 's honestly significant difference post-hoc tests were used for statistical comparisons between groups and Pearson χ (2 ) tests to compare the proportions . Kappa statistics was used to determine the interobserver agreement .The submucosa that appeared hypoechoic in the control groups had significantly increased echogenicity in the case group (hypo- to isoechoic in 46 .7 % and isoechoic in 53 .3 %). The differentiation between the submucosa and the muscle layer appeared distinct in the control groups while it was not clear in the case group (indistinct in 50 % and completely lost in 50 %). The number of sites found positive on the ultrasound was significantly greater than the number of clinically positive sites . There was a very good interobserver consistency in clinical and ultrasound findings .Ultrasonography of the buccal mucosa demonstrates increased submucosal echogenicity and reduced echo differentiation between submucosa and muscle layer in OSF cases . Hence , it can be used as a non-invasive imaging modality to assess the disease extent and severity across the entire buccal mucosa to supplement clinical evaluation .