Generality
Mucocele is a cystic formation characterized by an excessive accumulation of mucous secretion . This lesion manifests as a circumscribed swelling, bounded by an epithelium, similar to a bubble full of thick, clear and stringy liquid.
The mucocele can originate in various locations: in most cases, this lesion is evident in the oral cavity, but can also be seen in the appendix (after the obliteration of a lumen tract), in the gallbladder (from obstruction of the cystic duct) ), in the paranasal cavities and in other districts of the body.
The onset of this lesion can occur mainly in two ways:
- Traumatic or accidental rupture of a gland inside a tissue or an organ with mucous material sequestration (mucosal mucocele );
- Obstruction of physiological ducts or cavities with mucus leakage in the surrounding connective tissue, from which an inflammatory reaction occurs ( mucocele from extravasation ).
The mucocele can resolve independently, as the cystic formation tends to reabsorb spontaneously or undergoes breakage. If necessary, a surgical therapy is indicated, aimed at removing the lesion or emptying the cavity.
What's this
Mucocele is a reactive (non-infectious) lesion filled with mucous fluid, which is manifested by a distension of the mucosa. This swelling appears, therefore, as a cyst or a soft and fluctuating nodule.
Mucocele can potentially develop in any epithelium: paranasal sinuses, intestine, urogenital apparatus and so on.
Mucocele: types
There are two main types of mucocele:
- Mucocele or cyst from mucous extravasation;
- Mucocele or mucous retention cysts.
Extravasation and retention cysts share a clinical aspect, but differ from an etiopathogenetic and histopathological point of view.
Causes
Mucocele is a collection of mucus and other liquids caused by:
- From the obstruction of a duct or opening of a cavity
or
- From the traumatic rupture of a gland within a tissue or organ.
In the first case, in practice, the sequestration of mucous material ( retention cysts ) occurs, while in the second case, mucus escapes into the surrounding connective tissue, from which an inflammatory reaction occurs ( extravasation cysts ).
The onset of mucocele can be favored by various situations, such as, for example:
- Local traumas (eg biting lips or cheek, piercing, accidental breakage of a salivary gland etc.);
- Inflammations (phlogistic edema);
- Congenital malformations ;
- Tumors ;
- Calculations (eg scialolithiasis);
- Presence of scar tissue .
Mucocele: who is most at risk?
Mucocele is a lesion that can be observed in people of all ages, but it is very common in children and young adults, aged 10 to 30 years.
Symptoms and Complications
A mucocele occurs with the swelling of a mucous membrane, mobile and fluctuating. This cystic or nodular-like lesion develops slowly and can reach even considerable dimensions (from a few mm to a few cm).
In some districts, the mucocele is asymptomatic and, for many years, does not correlate to particular manifestations; at other times, however, this lesion increases in volume, compresses the neighboring organs and causes pain .
The swelling may decrease in size following the breakage of the lesion or reabsorption of the viscous extravasation, only to reappear later following reproduction and mucus collection.
In the tissues and in the organs in which it is not directly observable, the presence of the mucocele is revealed through a compressive or obstructive symptomatology.
Subsequent mucocele superinfection can cause abscess .
Oral mucocele
In the oral cavity, the mucocele occurs mainly at the level of the lower lip, but can also occur under the tongue or in the mucosa that covers the cheek internally.
Usually, the cyst manifests itself as a bulge of tense-elastic consistency and a smooth surface: many patients report feeling a bubble that tends to swell and deflate, like a balloon.
Normally, the mucocele does not hurt and tends to gradually increase in volume. Sometimes spontaneous rupture occurs with the discharge of thick liquid.
Oral mucocele is most commonly caused by trauma to the oral cavity, such as, for example: injury of the accidental lip or biting due to stress, piercing, accidental breakage of a salivary gland, use of orthodontic equipment or previous oral surgery.
In the oral cavity, the extravasation mucocele manifests itself following a trauma which, acting on the excretory duct of a salivary gland, causes its rupture with mucous leakage into the surrounding connective tissue and consequent inflammatory reaction.
The mucosal oral mucocele is due, instead, to the obstruction of the salivary flow; in this case, the gland swells creating the formation of mucocele. This pathological event can derive from a calculation (scialolithiasis), from the presence of scar tissue or from a neoplasm.
Ranula: what is it?
When it occurs in the oral floor, due to obstruction of the excretory duct of a minor salivary gland, the mucocele is also called ranula . This formation is, in practice, a retention cyst and is in the form of a smooth and rounded relief of pink or bluish color which lifts the buccal floor, pushing the tongue to the side. The ranula is not painful and may contain serous or mucous material; inside, usually, these mucoceles keep the saliva produced, which tends to concentrate.
Mucocele of nasal and paranasal sinuses
At the level of the nasal and paranasal sinuses, the mucocele can determine symptoms similar to those of chronic sinusitis. The cystic formation can also be associated with the appearance of intense pain, while the rhinorrhea is absent.
The mucocele of the nasal and paranasal sinuses can arise for various reasons, including phlogistic edema, maxillofacial trauma, congenital malformation or nasal polyposis . In practice, the sequestration of mucous material occurs due to the obstruction of the openings of the cavities that surround the nose, the orbit and the eye (it is, therefore, a retention cyst).
Mucocele of the nasolacrimal duct
The mucocele of the nasolacrimal duct generally derives from the non-perforation (physiological) of a thin mucous membrane, called the Hasner valve.
This condition is congenital (ie present at birth) and can involve:
- Sensation of tenderness of the orbit;
- Unilateral exophthalmos (protrusion of the eyeball);
- Epiphora (extravasation of tears from the conjunctival sac);
- Double vision (diplopia);
- Respiratory distress.
Mucocele of the appendix
The mucocele of the appendix is quite rare and, often, is discovered in a completely accidental way.
Diagnosis
A superficial mucocele can be diagnosed on the basis of a characteristic clinical history (eg a traumatic event, after which the appearance of the lesion occurred) and appearance (consistency, size, color, etc.).
In the absence of suggestive events that may indicate its aetiology, it is advisable to subject the cyst to a differential diagnosis with vascular lesions (hemangiomas) and soft tissue neoplasms (especially lipomas and neurofibromas) and / or salivary glands (eg mucus carcinoma). epidermoid). When it is not directly observable, the mucocele can be found accidentally or through diagnostic investigations performed to ascertain the reason for an obstructive or compressive symptomatology.
Mucocele: which tests are indicated?
In the process of ascertaining the nature of mucocele, imaging diagnostics are particularly useful:
- Computed tomography and magnetic resonance imaging are useful for identifying mucocele in its locations and for defining its characteristics;
- The ultrasound is usable in the abdomen, in the neck or in other districts that do not have a bony barrier;
- Two-dimensional radiology allows visualization of a mucocele, even indirectly (displacement of adjacent organs, bone erosion, etc.).
Finally, to confirm the suspicion, histological examination following biopsy or excision of the lesion is indicated.
Treatment
The management of the mucocele varies depending on the symptomatology, the location and the utility of the treatment itself.
Some superficial forms undergo a spontaneous process of regression, therefore they do not require treatment, resolving autonomously after a short time.
In most cases, however, it is necessary to aspirate the contents of the mucocele (an option that does not guarantee complete resolution) or surgical excision in its entirety.
Mucocele: surgery
The surgical option is indicated in cases where the mucocele is a disabling aesthetic or functional disorder for the patient.
If not treated, the mucocele can last several weeks or months, with a behavior characterized by periodic regression followed by recurrence or spontaneous rupture, with the emission of a racy mucous fluid.
Surgical removal of chronic mucocele or its marsupialization is followed by healing and helps prevent recurrences, as well as re-establishing the physiological channeling of a duct or cavity. Endoscopic techniques are increasingly used to avoid scarring, aesthetic deformities, paresthesias and other side effects.
