Mucocoele of paranasal sinus occurs commonly due to ongoing inflammation against closed drainage pathway of the sinus. Incidence of mucocoele is most common in frontal sinus followed by ethmoid sinus, less common in maxillary sinus. Moreover, incidence of bilateral maxillary mucocoele is of rare occurrence, has been classically described in children with cystic fibrosis or following open sinus surgery. Other causes of mucocoele being chronic sinusitis, allergic rhinosinusitis, trauma, previous surgery. Here we present a case report of a 26-year-old adult who was found to have bilateral maxillary mucocoele of uncertain aetiology, probably secondary to chronic sinusitis and further predisposed by anatomical variations in the sinus. Presentation, differential diagnosis and management by combined sublabial and endoscopic approach is discussed.
Mucocoeles are benign expansile cyst like lesions of paranasal sinuses. They occur because of an ongoing inflammatory process in an obstructed sinus.Mucocoeles are most commonly encountered in frontoethmoid region, and their occurrence in maxillary sinus is uncommon, found to be less than 10%. Overall, less than 5% were noted to be bilateral/ multiloculated. A Bilateral maxillary mucocele is rare clinical entity that has been reported only in infants with cystic fibrosis or following sinus surgeries such as Caldwell Luc operation[3-6]. In this case report, we thread through a case of bilateral maxillary mucocoele in a 26 year old adult of unknown etiology. Possible etiology, differential diagnosis, and optimal management modalities are discussed.
26-year-old adult male presented with complaints of purulent nasal discharge from bilateral nasal cavity for one year. He also had one episode of purulent discharge from left upper first molar region. He had no dental procedure or nasal surgery or trauma prior to these symptoms. There was no loosening of teeth, headache, epistaxis, displacement of eye or visual disturbances.
Nasal endoscopy shows bulging lateral nasal wall with polypoidal mucosa prolapsing in left middle meatus, purulent nasal discharge from bilateral middle meatus. Contrast enhanced Computerised Tomography (CT) was done which showed non-enhancing homogenous density filling bilateral maxillary sinus with remodelling of surrounding bone leading to thinning out and ballooning of all walls of maxillary sinus. There was extreme thinning of all walls including floor of sinus exposing root of tooth in the sinus. Biopsy of polypoidal mucosa at middle meatus showed inflammatory mucosa.Based on the clinical features and imaging, a working diagnosis of bilateral maxillary mucocoele or dental cyst is made. Patient was planned for bilateral Caldwell Luc approach under general anaesthesia due to suspected bone erosion of left maxillary sinus floor. Anterior wall of sinus was thinned out on both sides. On performing antrostomy, rupture of cyst wall noted with mucinous fluid filling the cyst in right maxillary sinus, and purulent fluid noted in the left one. Entire cyst wall removed, and no bony defect was noted along the floor of maxillary sinus on either side intraoperatively. Middle meatal antrostomy was done endoscopically to improve ventilation to the sinus. Combined approach i.e., canine fossa antrostomy by sublabial approach with endoscopic middle meatal antrostomy
was thus done. Postoperative period was uneventful. No
cheek anaesthesia or loosening of teeth was noted. sublabial
wound healed well.Diagnosis was made based on findings on
imaging and confirmed intraoperatively and histologically as
mucocoele and mucopyocoele. A five-month follow-up showed
no recurrence of symptoms.
Mucocoele are cystic expansible lesions lined by secretory
respiratory epithelium filled with mucus and characterized by
expansion and thinning of sinus walls. They are believed to arise
due to accumulation of mucus secondary to obstructed sinus
outflow while some believe that it may arise from an enlarging
mucous retention cyst filling entire sinus. While mucocoeles
are most common in frontal sinus followed by ethmoid sinus, they
are of rare occurrence in maxillary sinus accounting to 3-10%
of mucocoeles[7,8]. Maxillary mucocoelesare more common
in Japan as a long-term sequel after Caldwell Luc surgery,
presumed to be due to entrapped sinus mucosa. Apart from
these, common causes of maxillary sinus mucocoele are chronic
sinusitis, allergic rhinosinusitis, benign or malignant tumours
occluding ostiomeatal complex. Bilateral maxillary mucocoele
presentation is even rarer, and is classically seen in children with
cystic fibrosis, rarely even as a presenting feature. Mucocoele
can remain asymptomatic for a long time. Progressive expansion
of maxillary mucocoele leads to displacement of surrounding
structures and can cause proptosis, loosening of teeth, cheek swelling. Our patient here presented with purulent discharge
from bilateral nasal cavity, for an year and there was no history of
allergy, trauma or previous surgery.Discharge from upper molar
may be secondary to sinus infection or vice versa. The cause of
mucocoele remains uncertain, possibly due to chronic sinusitis.
Mucocoeles are best diagnosed by computed tomography (CT)
that shows homogenous non-enhancing soft tissue density
filling entire sinus with surrounding bony remodelling in terms
of thinning out and expansion. Differential diagnosis of soft
tissue density filling maxillary sinus includes, mucus retention
cyst, antrochoanal polyp, although, bony remodelling is not
classically seen in these. Surrounding bone destruction and
erosion should lead towards diagnosis of benign or malignant
tumours of sinonasal origin. In this case, CT showed expansile
lesion filling bilateral maxillary sinus with all walls ballooned
out with prominent medial extension on the left and focalerosion
of floor of maxillary sinus exposing root of teeth (Figure 1).
Bone erosion in mucocoele has been attributed inflammatory
cytokines, which trigger prostaglandins and collagenases
which in turn results in bone resorption[1,9]. Periapical cyst,
odontogenic cyst remained to be differential diagnosis. Caldwell
Luc approach was chosen to proceed with.Cystic lesion filling
maxillary sinus and filled mucus/ mucopus noted in maxillary
sinus. Although, floor of sinus was found intact during surgery
and septations were noted in maxillary sinus, as also seen in
preoperative CT (Figure 2), which might have led to localised
accumulation of mucus progressively and resulted in loculated
Bilateral maxillary mucocoeles are rare, have been
classically described in children with cystic fibrosis, or
following Caldwell Luc surgery[4,5]. This case we believe may
be secondary to chronic sinusitis, drainage in turn affected by
multiple septations in maxillary sinus predisposing to loculated
mucocoele formation.Mucocoele was managed by historically
by Caldwell Luc operation and removal of mucocoele lining.
Now the preferred treatment is endoscopic marsupialization
and wide middle meatal antrostomy[3,4]. Although, when
there is significant extension outside the sinus like facial tissue,
pterygopalatine fossa, open approach by Caldwell Luc surgery
is preferred for complete removal of mucocoele lining[1,3].
In this case, combined approach was used, where canine
fossa antrostomy was done to confirm diagnosis , to rule cyst
from dental origin, followed by middle meatal antrostomy
for ventilation of sinus. A five-month follow-up showed no
recurrence of symptoms or complications.
Bilateral maxillary mucocoele is of rare occurrence in adults
secondary to chronic sinusitis, and it may be predisposed
by intrasinus septations. Close differential diagnosis should
be considered based on symptomatology and imaging while
planning management. Endoscopic marsupialisation has good
outcome for maxillary mucocoele management, can be combined
with open technique by antrostomy to rule out close differential
diagnosis, and ensure complete removal of pathology.