Figure 1.

Sagittal T2-weighted MR image (A) in the median plane showing normal anatomy and the division of the oral cavity and oropharynx. Coronal T2-weighted image (B) and sagittal T2-weighted image (C) showing the various structures in the oral cavity. OC, oral cavity; OP, oropharynx; HP, hypopharynx; L, larynx; N, nasopharynx; H, hard palate; S, soft palate; Hy, hyoid bone; E, epiglottis. Muscles of the tongue: SG, styloglossus muscle; GG, genioglossus muscle; GH, geniohyoideus; IM, intrinsic muscles; Lg, superior longitudinal muscles; Tr, transverse lingual muscles. Muscles of the floor of the mouth: MH, myelohyoid muscle; D, anterior belly of the digastric muscle.