PÁGINA DEL RESIDENTE

 

What would your diagnosis be?

¿Cuál es su diagnóstico?

 

 

The patient was a 67-year-old woman whose only relevant medical history was sulfamide allergy and cholecystectomy. She was referred to our clinic by her primary care physician for the development over a year of a nodular mass on the floor of the left nasal cavity. The suspected diagnosis was nasal polyp.

The patient did not have nasal respiratory insufficiency, rhinorrhea, or nosebleed.

Nares were symmetrical on physical examination and there was no prominence of the left alar cartilage. The gingivolabial furrow was not swollen on intraoral examination.

Direct rhinoscopy revealed a nodular mass 1 cm in diameter below the left lower turbinate without turbinate hypertrophy or airway obstruction. The mucosa lining the mass was of normal characteristics without erosions or congestion (Fig. 1).

The patient also presented a mass on the floor of the right nasal cavity that was less noticeable than on the left side.

CT scan of the paranasal sinuses revealed a soft tissue cystic tumor on the floor of both nasal cavities, measuring 2-3 cm on the left and 1.5-2 cm on the right. There was no septal perforation or bone erosion due to maxillary compression (Figs. 2 and 3).

The patient was scheduled for surgery under general anesthesia. An intraoral approach via a sublabial incision was used to dissect and excise the lesions (Fig. 4).

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Bilateral nasoalveolar cyst

Quiste nasoalveolar bilateral

 

 

L. Pingarrón, R. Sánchez, M. Chamorro, I.Navarro, E. Mirada, M. Burgueño

Servicio de Cirugía Oral y Maxilofacial. Hospital Universitario La Paz. Madrid. España

Correspondence

 

 

 

The first description of nasoalveolar cysts, also known as nasolabial cysts, was by Zuckerkandl in 1882. It was not until 1892 that the first case was published in the Anglo- Saxon literature by Chatelier. Since then, there have been fewer than 200 documented cases.¹

Nasoalveolar cysts are more frequent in Caucasians and women with a female:male ratio of 3:1.

They typically occur in adults at an age of about 41 to 46 years, range 12 to 75 years.²

There does not seem to be any preference between the left and right locations. The bilateral presentation is infrequent (10–11.2% of published cases).

Only one case of malignant transformation of a nasolabial cyst has been documented.³

Histologically nasoalveolar cysts have a heavy wall of 1-2 mm consisting of 2 planes: a fibroconnective tissue capsule covered by epithelium. The type of epithelial cells present depends on several factors, including the history of cyst infection and size of the lesion. Consequently, epithelial cells can be transitional, squamous, pseudostratified, columnar, or cuboidal.

The cyst is filled with turbid fluid without keratinic material.

The fibrous capsule generally is firmly adhered to the floor of the nasal cavity.

The origin of these cysts is debated. The nose develops embyologically between the fourth and fifth week of gestation, at a moment when proliferation of mesenchymal tissue gives rise to the maxillary process and the medial and lateral nasal processes. Many theories have been formulated to explain the embryologic development of nasoalveolar cysts, of which the most accepted is epithelial entrapment in the zone of fusion of the maxillary, lateral nasal and medial nasal processes. The term "fissural cyst" has been coined to describe ectodermal remains in the fissure lines. Another theory explains the finding of septal tissue inside a nasoalveolar cyst by suggesting the entrapment of ectodermal tissue inside a displaced nasolacrymal duct.⁴

The treatment of nasoalveolar cysts is complete resection via a subnasal approach. A lateral rhinotomy approach has been used in cases of superior cyst extension.

In the clinical case presented, both cysts were resected with a band of approximately one centimeter of mucosa of the floor of the left nasal cavity. The incision was meticulously repaired and the sublabial incision was closed with absorbable suture. The left nasal cavity was packed with merocel and terramycin, which was removed on the third day without bleeding or swelling of the nasal vestibule or gingivolabial furrow.

The final histopathologic diagnosis was a mucous retention cyst lined with respiratory epithelium.

Resection is recommended not only to ensure an aesthetic result because the cyst can cause nostril asymmetry and displacement of the nasal alar cartilage, but above all to prevent recurrent infections and the associated pain.

The potential complications of surgery include fistulas and scar tissue formation. A band of mucosa of the floor of the nasal cavity often is excised with the cyst due to the firm adherence of the fibrous capsule. In this case the defect should be sutured and the intraoral approach closed meticulously to prevent complication with an oronasal fistula.

The differential diagnosis of premaxillary cysts is based on the tumor location and embryologic development of these cysts. Premaxillary cysts can be divided into 3 categories: fissural, odontogenic, and infectious.

Fissural cysts are subdivided, in turn, into medial and lateral cysts.

Medial fissural cysts include dermoid cysts and medial alveolar, medial palatal and nasopalatal cysts, which in turn include the cysts of the incisor canal and cysts of the palatal orifice.

Globulomaxillary cysts form the lateral group and originate from the same site as nasoalveolar cysts. However, globulomaxillary cysts are inclusion cysts absorbed into the bone, whereas nasoalveolar cysts pertain to the soft tissues overlying the bone plane.

Odontogenic cysts derive from the dental lamina and are distinguished from other lesions by imaging studies. Radicular cysts (lined by stratified squamous epithelium) belong to this group, as well as dentigerous cysts (which contain dental remnants and also are lined by stratified squamous epithelium) and primordial cysts (which are associated with congenital absence of teeth).

The group of cysts of infectious origin, such as furuncles of the floor of the anterior nasal cavity or vestibule, can simulate the form of presentation of nasoalveolar cysts.

 

Discussion

Nasoalveolar cysts are an uncommon pathology pertaining to the group of nonodontogenic cysts or fissural cysts, which arise from the nasoalar facial region; the bilateral location is even more exceptional.⁵ The diagnosis is fundamentally clinical and based on intraoral and intranasal examination by direct rhinoscopy. The differential diagnosis is fundamentally with furuncles of the nasal vestibule and premaxillary cysts of odontogenic and fissural origin.

The definitive treatment to prevent recurrence is surgical resection via a sublabial approach, with repair of the nasal mucosa and careful closure of the maxillary vestibule in the case of perforation to prevent oronasal fistulas.

 

 

Correspondence:
Lorena Pingarrón Martín
Servicio de Cirugía Oral y Maxilofacial. Hospital Universitario La Paz.
Pº de la Castellana, 261. 28046 Madrid. España
E-mail: lorenapingarron@yahoo.es

 

References

1. Cummings CW. Otolaryngol Head Neck Surgery. 2^nd ed. St Louis: Mosby; 1992; 1237.        [ Links ]

2. Hynes B, Martin LC. Nasolalveolar cysts: a review of two cases. J Otolaryngol 1994;23:194-6.        [ Links ]

3. Bull TR, McNeill KA, y cols. Naso-alveolar cysts. J Laryngol Otol 1967;81:37-44.        [ Links ]

4. Liu ES, Kridel RWH. Evaluation of nasoalvelar cyst for the facial plastic surgeon. Arch Facial Plast Surg 2003;5:185-8.        [ Links ]

5. Tanimoto K, Kakimoto N, y cols. MRI of nasoalveolar cyst: Case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2005;99;221-4.        [ Links ]