<unk>  is usually diagnosed clinically. Sleep endoscopy and imaging may be used for assessment of obstructive sleep apnea. The initial evaluation of all patients with<unk>  may involve abdominal ultrasound and molecular studies for Beckwith–Wiedemann syndrome. Classification The ICD-10 lists<unk>  under "other congenital malformations of the digestive system". Definitions of<unk>  have been proposed, including "a tongue that protrudes beyond the teeth during resting posture" and "if there is an impression of a tooth on the lingual border when the patients slightly open their mouths". Others have suggested there is no objective definition of what constitutes<unk> . Some propose a distinction between true<unk> , when histologic abnormalities correlate with the clinical findings of tongue enlargement, and relative<unk> , where histology does not provide a pathologic explanation for the enlargement. Common examples of true<unk>  are vascular malformations, muscular enlargement and tumors; whilst Down syndrome is an example of relative<unk> . Pseudomacryglossia refers to a tongue that is of normal size but gives a false impression of being too large in relation to adjacent anatomical structures. The Myer classification subdivides<unk>  into generalized or localized.
Macroglossia
Macrodontia 
Hypoglossia
Macrognathism
Asymmetric crying facies
Ankyloglossia
Elfin facies
Spotted lunulae