Lingual Tonsil: Anatomy, Function, and Clinical Significance

The lingual tonsil is a collection of lymphoid tissue located at the base of the tongue (posterior third), forming part of Waldeyer's ring—the ring of lymphoid tissue guarding the aerodigestive tract.

Anatomy & Histology

• Covered by respiratory epithelium with deep invaginations (crypts) that increase surface area for antigen exposure.
• Rich in B and T lymphocytes; produces secretory IgA and IgG.
• Drains to deep cervical lymph nodes (levels II–III).

Immune Function

Acts as a first-line defense against ingested and inhaled pathogens. The crypts sample antigens, initiating local immune responses and lymphocyte activation.

Clinical Conditions

• Lingual tonsillitis: Sore throat, dysphagia, otalgia (referred ear pain), and "hot potato" voice.
• Hypertrophy: Can cause obstructive sleep apnea, globus sensation, or airway obstruction.
• Lymphoma: Primary or secondary involvement (e.g., diffuse large B-cell lymphoma).
• Abscess: Rare but potentially life-threatening due to airway compromise.

Examination & Diagnosis

Visualization requires indirect laryngoscopy, flexible nasopharyngoscopy, or cross-sectional imaging (CT/MRI). Biopsy is indicated for persistent asymmetry, ulceration, or suspicion of neoplasm.