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Topic

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Dorsum of tongue

The dorsum of the tongue refers to the upper (superior) surface of the tongue, extending from the tip to the terminal sulcus posteriorly. It is divided into anterior two-thirds (oral part) and posterior one-third (pharyngeal part/base of tongue) by the V-shaped terminal sulcus, with the foramen cecum at its apex. The surface is covered with specialized mucosa containing lingual papillae—filiform, fungiform, circumvallate, and foliate—that contribute to tactile sensation, taste, and mechanical functions. The dorsum has a thin layer of connective tissue and minor salivary glands and overlays intrinsic and extrinsic muscles, allowing mobility and shaping of the tongue during speech, mastication, and swallowing.

Synonyms

  • Superior surface of tongue

  • Tongue dorsal surface

  • Lingual dorsum

Function

  • Houses taste buds for gustatory sensation

  • Provides tactile sensation for food manipulation

  • Aids in speech articulation and swallowing

  • Supports mastication by guiding food toward teeth and posterior oral cavity

  • Protects oral cavity through mechanical friction with teeth and palate

Nerve Supply

  • Motor: Hypoglossal nerve (CN XII) – intrinsic muscles underneath dorsum

  • Sensory (general sensation): Lingual nerve (CN V3) – anterior two-thirds

  • Special sensory (taste): Chorda tympani (CN VII) via lingual nerve – anterior two-thirds; glossopharyngeal nerve (CN IX) – posterior one-third

  • Minor sensory contributions: Vagus nerve (CN X) – for circumvallate papilla region and epiglottic taste

Arterial Supply

  • Lingual artery (branch of external carotid artery)

    • Dorsal lingual branches – supply dorsum of tongue

    • Deep lingual artery – mainly anterior dorsum and tip

  • Sublingual artery – contributes near anterior floor of mouth

Venous Drainage

  • Lingual veins, including dorsal lingual veins and deep lingual veins, drain into the internal jugular vein

  • Venous plexuses lie beneath mucosa, especially near tip and lateral borders

MRI Appearance

T1-weighted images:

  • Dorsum musculature appears intermediate signal intensity

  • Surrounding subcutaneous and submucosal fat appears hyperintense, providing contrast

  • Air in the oral cavity or oropharynx appears as signal void (black)

  • Papillae and mucosal surface may appear as slightly heterogeneous areas on high-resolution imaging

  • Pathology (tumors, edema) appears hypo- to isointense

T2-weighted images:

  • Muscle tissue remains intermediate signal, while edema, inflammation, or fluid collections are hyperintense

  • Papillae and connective tissue variations may be visible

  • Air remains a signal void, clearly outlining the dorsum

STIR (Short Tau Inversion Recovery):

  • Suppresses fat, highlighting pathological changes such as edema, infection, or tumor

  • Normal musculature appears intermediate to low signal, while abnormalities appear bright hyperintense

  • Air continues to appear as a signal void, preserving anatomical boundaries

CT Appearance

  • The dorsum appears as a soft tissue density structure in the oral cavity

  • Air in the oral cavity is hypodense (black), sharply outlining the tongue surface

  • Papillae are usually not directly visualized, but the tongue surface contour is clear

  • Muscles are seen as homogeneous soft tissue density, adjacent to the mandible and oral floor

  • Useful for tumor evaluation, trauma, and foreign body detection

MRI images

Dorsum of tongue mri axial image -img-00000-00000

MRI images

Dorsum of tongue mri sag image -img-00000-00000