Keywords not odontogenic cyst - nasal obstruction - cysts
Palavras-chave cistos não-odontogênicos - obstrução nasal - cistos
Introduction
The nasoalveolar cyst is a rare benign lesion, located in topography of nasolabial
folds, anteroinferior of the piriform rim of nasal cavity. It́s a lesion that is usually
unilateral (90% of the cases)[1 ]
[2 ], affecting mainly people of black race, of feminine gender, in the age group which
comprises between the 4th and 5th decades of life[1 ]
[2 ].
The first to describe this pathology was Zuckerkandl in 1882[3 ]. This embryonic, non-odontogenic, usually asymptomatic, being diagnosed late, due
to the facial aesthetics changes and breathing. Although diverse synonymy (nasoalveolar
cyst, Klestadt cyst, congenital mucoid cyst of the nasal edge), the term considered most appropriate,
at the moment, is nasolabial cyst[4 ].
Besides literature review, this study has as objective, report the case of a patient
with bilateral nasoalveolar cyst, presenting clinical aspects, surgical, histopathological
and radiographic.
Case Report
Patient AWV, feminine gender, 24 year-old, mulatto, coming and natural of São Paulo,
housewife, sought for treatment at Otorhinolaringoloy Paulista Hospital, SP, Brazil,
complaining about bulge region of bilateral nasolabial, of progressive evolution for
about 06 months, associated to the nasal obstruction in the last 02 months. Patient
denied pain, rhinorrhea, nasal itching, sternutatory, epistaxis or other nasal complaints.
At the otorhinolaryngological examination, it was observed bulging without signs of
inflammation at bilateral nasolabial region and superior gingivolabial sulcus, especially
on the right, raising the nasal floor and erasing the bilateral nasolabial folds.
The computerized tomography of paranasal sinuses showed two cystic lesions parallel
to the bilateral nasal spine ([Figure 1 ]), nasal floor bulging, depression in the anterior maxillary bone bilateral and displacement
of the anterior portion of inferior turbinate left up ([Figure 2 ]).
Figure 1. Computerize Tomography shows bilateral nasolabial cyst, obstructing the nasal cavity
and forming bone erosion.
Figure 2. Nasolabial cyst moving the anterior portion of the inferior nasal turbinate upwards.
For this case, we had chosen to perform the surgical excision of the lesion, at surgical
room , under general anesthesia. After local infiltration of anesthetic solution (Lidocaine
at 2% with epinephrine 1:100.000), central incision was made (approximately 6,0 cm)
in the superior gingivolabial sulcus, below the cystic lesions, between the lateral
incisors of both sides, followed by detachment of the anterior region of cysts, with
visualization of these two lesions separated by a bony septum, the left side measuring,
approximately 2,0cm and the right side, around 3,0cm ([Figure 3 ]). It was performed a dissection of the right cyst, initially, preserving its contents,
being possible the detachment of the lateral walls. It was located the nasal floor
plane (nasal mucosa) at the superior region of the cyst; at this point, for better
detachment, it was chosen by emptying the contents serous, with yellowish color, of
the cyst by needle and syringe. After emptying the cyst, it was performed a careful
dissection in its upper portion, which kept contact with nasal mucosa, region where
it presented greater adherence. The displacement was performed without lesion of the
nasal mucosa. At the back region of the cyst, the displacement showed planes less
adhered, facilitating the removal. The same surgical technique was performed at the
left side of the cyst, being possible to indentify the nasal floor mucosa and perform
the removal without lesion ([Figure 4 ]). Synthesis was performed at plans dissected, with absorbable lines (Catgut 2-0,
simple).
Figure 3. Intraoperative showing bilateral nasolabial cysts. Vision through the Denker incision.
Figure 4. The operative field after removal of nasolabial cysts, presenting bone erosion.
At immediate postoperative, patient complained of paresthesia at anterior region of
the upper lip and nasal vestibule, which remained for 03 months.
Patient is at ambulatory accompaniment of postoperative for 06 months, without evidences
of recurrence or other changes, presenting improvement of nasal obstruction.
Anatomopathology
It was sent for histological study, two cystic structures previously sectioned, conserved
in formaldehyde, and represented wall studs, smooth and bright, with shades of brown
color. The larger structure measured 3 × 2,5 × 1 cm and the smallest, 2,5 × 1,5 × 0,5cm.
The sample was submitted to the processing chemical pradronized, obtaining a block
of paraffin to each cystic structures, being made the respective histological concoction,
with thickness of 5 (five) micra and color by the technique of hematoxylin-eosin and
PAS (Schiff periodic acid).
The histological study revealed identical aspect in both lesions, being identified
of cystic wall constituted by loose connective tissue showing moderate edema, covered
by two different types of epithelium: the predominant was of the type stratified squamous,
with preservation of the polarity and absence of nuclear atypia, removing away the
suspicion of malignancy.
The other type of epithelium was constituted by one or two layers of cylindrical cells
sometimes massive clear vacuoles in the cytoplasm ([Figure 5 ]), that special color by the technique of PAS revealed weak positivity to the mucopolysaccharide
substances ([Figure 6 ]). At the connective tissue wall, the histological sections revealed nerve fibers
and blood capillaries of ecstatic lights, alongside to the moderate interstitial edema.
Some muscle striated fibers was also indentified at the region of surgical region.
Figure 5. 400X – nasolabial cyst - hematoxylin-eosin. Observe the pluri squamous epithelium
formed by the poligonal cells, abundant cytoplasm and acidophilic around the round
nuclei, isochromatic. Superficially, single layer of cylindrical cells showing vacuolated
and clear cytoplasm.
Figure 6. 400X – nasolabial cyst - PAS. Note accumulation of PAS-positive granules in the cytoplasm
of the cell located in the center of the microscopic field.
The anatomopathological diagnosis was of bilateral nasolabial cyst.
Discussion
The nasoalveolar cyst is an embryonic cyst, non-odontogenic, which has its controversial
origin , being the theories based on:
cyst originated from the invagination of ectodermal debris among the processes nasal
side and media being for that reason, considered as fissural cyst (Klestadt Theory,
1913)[1 ]
[5 ]
[6 ];
cyst derived from the epithelium of the nasolacrimal duct during the embryonic period
(Bruggemann Theory, 1920)[5 ]
[7 ].
For reason of its poor symptomatology, this disease is underdiagnosed[8 ], showing in the literature, an incidence of 0,7% of all maxillofacial cysts and
2,5% of non-odontogenic cysts. In the presented case, we observed a mulatto patient,
even being more common at black race, according to the literature. Epidemiological
data shows that this cyst is more frequent in persons of feminine gender, in the proportion
of 4:1 (when unilateral) and 5,5:1 (when bilateral)[9 ]. The age group most affected includes the 4th an 5th life decades[2 ]
[3 ]
[7 ]. The cysts presentation is most unilateral (90%), being only10% bilateral[1 ]
[2 ]
[8 ].
Clinically, this lesion presents as a bulging of slow growing located at the portion
ventral inferior of piriform fossa region. In the course of time, the cyst leads to
a facial deformity with a deletion of nasolabial folds, nasal obstruction by the elevation
of nasal floor and superior displacement of the anterior portion of the inferior turbinate.
It is worth to highlight that the dentition remains intact[6 ]. Eventually, it may occur cyst infection (50% of the cases), presenting signs of
inflammation. In this infection cases, it can occur the cyst drainage to the oral
cavity and /or to the nasal vestibule[3 ]
[6 ].
The diagnosis of nasoalveolar cyst is clinical and topographic, with visual and palpation
of the affected area[6 ]. The workup done by the imaging examination confirms the suspicion and the clinical
examination, being the Computerized Tomography the examination of choice, which may
show, in some cases, jawbone erosion[10 ]
[11 ]
[12 ]. The nasolabial cyst consists of lesion in the soft parts, and for this reason,
the x-ray being considered an obsolete examination, capable to show few details; except
in the cases in which the cyst presents gigantic dimensions leading to the significant
erosion of the jawbone.
The differential diagnosis which must be done with the nasolabial cyst include the
dermoid , nasopalatine, median palatal, median alveolar, globulomaxilar cysts (which
origin in the interior of the bone), besides of furuncles at nasal floor, which resembles
to infected nasolabial cyst[13 ].
in the literature, it has been reported Just one case (Arnold, 1929) of nasolabial
cyst which evolves to carcinoma[9 ]
[14 ].
Although there are reports of treatment of nasolabial cyst by sclerosing substances
or marsupialization[15 ], the most indicated therapy found in the literature is surgical removal. Enucleation
can be performed with local anesthesia or general, being the best way to access the
Denker incision ( intra-oral incision, sublabial next to the incisive fossa) which
offers an ample exposition. During the surgery, should take in account the cyst intimate
adherence with the nasal floor[3 ]
[16 ], detail that, constantly, leads to the laceration of the mucosa in this region of
the nose. This was possible to avoid in this case, in which we had chosen to empty
the cystic contents to obtain a better dissection of the cyst in relation to this
region of nasal floor. The closing of the planes should be complete, in order to avoid
possible oronasal fistulas. By the reason the extension of the cysts related did not
affected the region of nasal wing, it was not necessary apply any technique to avoid
retraction. The surgery aims the facial esthetic restoration, the nasal function (in
case it is affected) and the prevention of recurrent infections, which can be associated,
and minimize the patient anxiety
The surgical treatment present few complications, among them may recede with deformity
of the nasal ala, mainly in Blacks and still, oronasal fistula. Recurrence of the
cyst is rare and the prognosis is very good[5 ]
[7 ].
The description of the surgical technique in this case, aims to provide a foundation
to help similar cases in order to obtain surgical success, without submit the patient
to complications and disease recurrence.
