Review articles

By Dr. Balasubramanian Thiagarajan , Dr. Karthikeyan Arjunan
Corresponding Author Dr. Balasubramanian Thiagarajan
Department of Otolaryngology, Stanley Medical College, Chennai Tamilnadu, Sreemagal, 20 I Street, Officers Colony, Rajaram Metha Nagar - India 600029
Submitting Author Dr. Balasubramanian Thiagarajan
Other Authors Dr. Karthikeyan Arjunan
Otolaryngology Stanley Medical College, - India


Mucocele, Paranasal sinuses, Rhinology, Otolaryngology

Thiagarajan B, Arjunan K. Mucoceles of Paranasal Sinuses. WebmedCentral OTORHINOLARYNGOLOGY 2012;3(4):WMC003263
doi: 10.9754/journal.wmc.2012.003263

This is an open-access article distributed under the terms of the Creative Commons Attribution License(CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submitted on: 18 Apr 2012 08:08:59 AM GMT
Published on: 18 Apr 2012 01:15:56 PM GMT


Mucoceles are gradually expanding lesion involving paranasal sinuses. This is usually caused due to obstruction to the normal drainage channels of paranasal sinuses leading on to pent up secretions within it. These patients classically don’t present with symptoms pertaining to nose and sinuses but with ophthalmological signs and symptoms. They invariably present to the opthalmologist before finding their way to an otolaryngologist.


A mucocele is defined as mucous filled epithelium lined sac. Mucoceles commonly involve ethmoidal and frontal sinuses. Mucoceles are commonly caused due to obstruction to drainage channel of paranasal sinuses. These expansile cystic masses are sometimes filled with mucopurulent secretions [1]. Sometimes associated bone destruction is also evident [2].
Mucoceles are rather common in frontal sinuses. Next comes the ethmoidal sinuses. Isolated mucoceles involving ethmoidal sinuses are rather rare [5]. They always occur in combination with frontal /sphenoid mucoceles [4]. The term mucocele was first coined by Rollet in 1896. Onodi first described histology of Mucocele in 1901.


Mucoceles have been postulated to form due to obstruction of sinus ostia following chronic infections / allergic reactions involving paranasal sinuses [3]. Previous trauma / surgery can also cause obstruction to sinus outflow channels causing formation of mucoceles. Ethmoiodal mucoceles if present in isolation could be caused by endoscopic ethmoidectomy. Some studies have reportedoccurrence of isolated ethmoidal mucoceles even 10 years after surgery [6]. Paranasal sinuses continues to expand slowly owing to pent up mucous secretions. These mucoceles are lined by dilated ciliated columnar epithelium which secrete mucous causing expansion of the cyst. Continuing expansion of this cyst puts pressure on the bony walls of paranasal sinuses, causing bony erosion andremodeling. Unchecked extension of sinus cavity can cause extension of mucocele into orbit, nasopharynx and cranial cavity[9]. In addition to pressure changes inflammatory mediators like prostaglandins, interleukins and tumor necrosis factor present within mucoceles also contribute to their expansion capability [10].
Three main theories of pathogenesis of mucocele formation has been postulated[8]:
1. Pressure erosion
2. Cystic degeneration of glandular tissue
3. Active bone resorption and regeneration

Sites involved by mucoceles [7]

1. Anterior ethmoid
2. Frontal
3. Maxilla
4. Posterior ethmoid
5. Sphenoid
About 60% of paranasal sinus mucoceles are present in the frontoethmoidal region [11].

Relationship between endoscopic sinus surgery and mucocele formation

Endoscopic surgery can cause mucocele formation due to adhesions developing in the middle meatus. This complication can be prevented by taking care not to damage normal mucosa. Retention of healthy mucosa in the middle meatal area prevents adhesions from occurring. Meticulous post operative endoscopic cleaning of crusts will help in minimizing adhesion formation. Routine middle turbinate excision while performing endoscopic sinus surgery was previously considered to minimize adhesions from occurring in the middle meatus area. Adhesions can still form in other areas of nasal cavity. In fact adhesions can form between remnant middle turbinate and lateral nasal wall [6]. Studies have revealed that it could take anywhere between 5 – 10 years [6] before mucocele develops, hence it is important to elicit history of paranasal surgery in these patients.

Clinical features

Usually patients with mucoceles involving paranasal sinusesdon’thave nasal / sinus symptoms. Only symptoms they present with are ophthalmological in nature.
1. Pain: This is commonly periorbital in nature. This is caused by inflammation and stretching of nasal and sinus mucosa, rarely from dura. Pain is usually transmitted by trigeminal nerve [12].
2. Progressive proptosis
3. Visual disturbances (diplopia) / blurring of vision: This is caused by erosion of the bony casing around optic nerve. Any further expansion of mucocele will cause compression of optic nerve compromising its blood supply. Infections from mucocele can reach the optic nerve when the bony casing around the optic nerve is breached by the enlarging mucocele [14].
4. Epiphora
5. Impaired ocular mobility.

Role of Imaging

Radiological images of sinuses demonstrate thinning and expansion of affected paranasal sinus walls. Sinuses affected by mucoceles usually appears homogenous and airless. Plain x-ray of paranasal sinus mucoceles show the following features:
1. Soft tissue density mass seen obliterating sinuses
2. Expansion of paranasal sinus
3. Evidence of bone thinning and erosion
CT scan shows lesions with greater clarity. Precise extension of the lesion can be assessed by studying CT scan images. Scans reveal well defined expansile lesion with obliteration of paranasal sinus air cell cavities.
Size of the swelling (external) caused by frontoethmoidal mucoceles increases in size gradually. The rate of expansion of frontoethmoidal mucocele is accelerated if secondary infection is present within mucocele [13].

Classification of frontal mucocele

Frontal mucoceles have been classified into 5 types depending on its extent.
Type I: In this type the mucocele is limited to the frontal sinus only with or without orbital extension.
Type II: Here the mucocele is found involving the frontal and ethmoidal sinuses with or without orbital extension.
Type IIIa: In this type the mucocele erodes the posterior wall of the frontal sinus with minimal or no intracranial involvement.
Type IIIb: In this type the mucocele erodes the posterior wall with major intra cranial extension.
Type IV: In this type the mucocele erodes the anterior wall of the frontal sinus.
Type Va: In this type there is erosion of both anterior and posterior walls of frontal sinus without or minimal intracranial extension.
Type Vb: In this type there is erosion of both anterior and posterior walls of frontal sinus with a major intracranial extension.


Mucoceles are ideally managed surgically. Before the advent of endoscopic procedures, External frontoethmoidectomy was considered to be the ideal management modality.
Classification of surgical approaches:
I. Transnasal approach:
* Endoscopic sinus surgery
* Microscopic sinus surgery
* Trans sphenoidal approach
II. External approaches:
* Caldwel Luc approach
* Osteoplastic frontal sinus surgery
* External Ethmoidectomy
* Lateral rhinotomy
* Craniofacial resection
Endoscopic procedures are currently the commonly used surgical approach in managing mucoceles.


1. Canalis RF, Zajtchuk JT, Jenkins HA. Ethmoidal mucoceles. Arch Otolaryngol Head Neck Surg 104:286-291, 1978.
2. Natvig K, Larsen TE. Mucoceles of the paranasal sinus. J Laryngol Otol 92: 1075-1 082, 1982.
3. Evans C. Aetiology and treatment of fronto-ethmoidal mucocele. J Laryngol Otol 95:361-375,1981.
4. Lai PC, Liao SL, Jou JR, et al. Transcaruncular approach for the management of frontoethmoid mucoceles. Br J Ophthalmol 2003;87: 699-703.
5. Christmas DA, Mirante JP, Yanagisawa E. Isolated ethmoid sinus mucocele. ENT Rhinoscopic Clinic 2002;759-60.
6. Busaba NY, Salman SD. Ethmoid mucocele as a late complication of endoscopic ethmoidectomy. Otolaryngol Head Neck Surg 2003;128: 517-22.
7. Sinus mucocele: Natural history and long-term recurrence rate M. Devars du Mayne, A. Moya-Plana, D. Malinvaud, O. Laccourreye, P. Bonfils European Annals of Otorhinolaryngology, Head and Neck diseases (2012)
9. Lai PC, Liao SL, Jou JR, et al. Transcaruncular approach for the management of frontoethmoid mucoceles. Br J Ophthalmol 2003;87: 699-703.
10. Conboy PJ, Jones NS. The place of endoscopic sinus surgery in the treatment of paranasal sinus mucoceles. Clin Otolaryngol 2003;28:207-10.
11. Har-El G. Endoscopic management of 108 sinus mucoceles. The Laryngoscope. 2001;111:2131---4.
12. Moriyama H, Hesaka H, Tachibana T, Honda Y. Mucoceles of ethmoid and sphenoid sinus with visual disturbance. Arch Otolaryngol Head Neck Surg 1992;118:142–6.
13. Lai PC, Liao SL, Jou JR, et al. Transcaruncular approach for the management of frontoethmoid mucoceles. Br J Ophthalmol 2003;87: 699-703.
14. Yumoto E, Hyodo M, Kawakita S, Aibara R. Effect of sinus surgery on visual disturbance caused by spheno-ethmoid mucoceles. Am J Rhinol 1997;11:337–43.

Source(s) of Funding

This article did not receive funding from any external source.

Competing Interests

Authors dont have anything to report pertaining to competing interest while authoring this document.


This article has been downloaded from WebmedCentral. With our unique author driven post publication peer review, contents posted on this web portal do not undergo any prepublication peer or editorial review. It is completely the responsibility of the authors to ensure not only scientific and ethical standards of the manuscript but also its grammatical accuracy. Authors must ensure that they obtain all the necessary permissions before submitting any information that requires obtaining a consent or approval from a third party. Authors should also ensure not to submit any information which they do not have the copyright of or of which they have transferred the copyrights to a third party.
Contents on WebmedCentral are purely for biomedical researchers and scientists. They are not meant to cater to the needs of an individual patient. The web portal or any content(s) therein is neither designed to support, nor replace, the relationship that exists between a patient/site visitor and his/her physician. Your use of the WebmedCentral site and its contents is entirely at your own risk. We do not take any responsibility for any harm that you may suffer or inflict on a third person by following the contents of this website.

1 review posted so far

0 comments posted so far

Please use this functionality to flag objectionable, inappropriate, inaccurate, and offensive content to WebmedCentral Team and the authors.


Author Comments
0 comments posted so far


WebmedCentral Article: Mucoceles Of Paranasal Sinuses

What is article Popularity?

Article popularity is calculated by considering the scores: age of the article
Popularity = (P - 1) / (T + 2)^1.5
P : points is the sum of individual scores, which includes article Views, Downloads, Reviews, Comments and their weightage

Scores   Weightage
Views Points X 1
Download Points X 2
Comment Points X 5
Review Points X 10
Points= sum(Views Points + Download Points + Comment Points + Review Points)
T : time since submission in hours.
P is subtracted by 1 to negate submitter's vote.
Age factor is (time since submission in hours plus two) to the power of 1.5.factor.

How Article Quality Works?

For each article Authors/Readers, Reviewers and WMC Editors can review/rate the articles. These ratings are used to determine Feedback Scores.

In most cases, article receive ratings in the range of 0 to 10. We calculate average of all the ratings and consider it as article quality.

Quality=Average(Authors/Readers Ratings + Reviewers Ratings + WMC Editor Ratings)