Macroglosia

Macroglossia, meaning large tongue, has been a documented anatomical anomaly for several centuries but remains an entity defined more by presentation than by strict cephalometric analysis. The earliest known written description of tongue lesions comes from the Egyptian Papyrus Ebers, originally thought to be from around 1550 BC.
Obviously, tongue lesions have since been categorized by their etiologies. Macroglossia has an extensive list of possible causes. Its treatment has been largely surgical in the modern era.

Problem

Multiple studies have attempted to define macroglossia by objective measurements based on a variety of clinical and radiographic tests. However, because of the difficulty in performing these tests and because intervention is not based on measurements but on clinical presentation, macroglossia is most often diagnosed subjectively.
Ueyama and others defined macroglossia as occurring when  of the following  criteria is met:extravasation of the lingual apex or lingual border onto or outside the dentition;  the impression of one or more teeth on the lingual border visualized when the mouth is open; or  following surgery for correction, a relapse of increased interdental space, open bite deformity, and/or jaw deformation with malocclusion occurs.
As with many lesions, medicine has identified a triad for those with macroglossia. It includes open bite deformity, mandibular prognathism, and malalignment.

Epidemiology

Frequency

Although the exact incidence of macroglossia is unknown (because the etiologies are too numerous to quantify), some congenital syndromes often express macroglossia in their phenotypes, most commonly Down syndrome (1 per 700 live births) and Beckwith-Wiedemann syndrome (0.07 pre 1000 live births). In Beckwith-Wiedemann syndrome, 97.5% of patients have macroglossia.The literature documents 2 families with autosomal dominant inheritance of isolated macrogloss

Pathophysiology

Because the pathophysiology of the enlarged tongue is related to the specific etiology, defining the pathophysiology of each is beyond the scope of this discussion. However, in all cases, the locoregional complications of macroglossia are generally the same relative to the magnitude of the enlargement. Mechanical obstruction in the oral cavity can directly occlude the airway. This occlusion is usually worsened by lying supine when an enlarged tongue base is more directly acted upon by gravity to block the oropharynx and hypopharynx. Depending on muscle mass and tone, speech and swallowing may be affected as well.
Several studies document the role of the tongue in shaping the oral cavity. Just as reduced pressure of the tongue on the palate and mandible may lead to an adenoid facies, increased pressure on the surrounding anatomy can have opposite effects. Upper incisors can be pushed horizontally, inducing forward maxillary growth. Other morphologic changes include open bite deformities, prognathism, class III malocclusion, anterior and/or posterior crossbites, buccal tipping of posterior teeth, accentuated curve of Spee in the maxillary arch, reverse curve of Spee in the mandibular arch, increased transverse width of mandibular and/or maxillary arches. Furthermore, difficulty with mastication may lead to temporomandibular joint pain.
If the tongue protrudes beyond the lips and is exposed to the air, drying of the tongue with resultant glossitis and bleeding is common. Prior to the 1900s, this was not an uncommon occurrence for patients.

Indications

Indications for surgical intervention are varied. The most important is airway compromise. A tracheostomy may be required as a first step in surgical care (in some cases an elective tracheostomy is performed prior to surgical correction). Other indications include dysarthria, dysphagia, and cosmesis.
The goal of nearly all surgery is to return the patient to an anatomically and physiologically normal condition; the same is also true in surgery for macroglossia. The goal is to reduce tongue size and thereby improve function. Those main functions include articulation, mastication, deglutition, protection of the airway, and gustation. Of these, only gustation is not often improved with surgical intervention.

Contraindications

As with all intervention, whether medical or surgical, the benefits of the operation must outweigh the risks. Relative contraindications are those associated with most surgeries and include coagulopathies and other comorbidities that make general anesthesia more dangerous. In the pediatric population, many cases of macroglossia are associated with syndromes that may have lesions that increase the risk of general anesthesia.