Abstract
The sphenoid sinus mucoceles are rare and have an incidence of 1%, when sufficiently large they can compress optic canal, superior orbital fissure and vital structures causing optic neuropathy, ptosis, ophthalmoplegia and diplopia. We herein report a 73 year old male who presented with headache and left lateral rectus palsy secondary to sphenoid sinus mucocele which was confirmed on MRI and successfully treated with endoscopic marsupialization.
Keywords: Sphenoid mucocele, Endoscopic sinus surgery, MRI scan, Acute Cranial nerve palsy
Introduction
Paranasal sinus(PNS) mucoceles are slow growing benign cystic lesions lined with the respiratory epithelium that contain mucoid secretions leading to sinus expansion, bony erosion and extension into orbit, cranial cavity and nasopharynx [1]. Frontal mucocele is most common, but sphenoid mucocele occurs rarely and have incidence of 1% [2]. Sphenoid sinus is closely related to cranial nerves 2–6, internal carotid artery (ICA), pituitary gland and cavernous sinus and hence tend to have extremely variable clinical presentation. Symptoms can range from headache, visual disturbance and neurological symptoms reported in prolacting secreting pituitary adenomas.Treatment is surgical and endonasal endoscopic marsupialisation is preferred approach [3]. Marsupialisation by partial removal of anterior and inferior walls of mucocele prevents recurrences and complications in most of the cases [4]. In this article we emphasize importance of early diagnosis with the help of imaging and prompt management is critical in recovering visual potential.
Case Report
A 73 year old male patient came to the ophthal OPD with complaints of headache since 7 days, double vision and restricted movements in the right eye since 7 days, on examination the patient was diagnosed to have right lateral rectus palsy and underwent MRI brain which showed the sphenoid sinus to be expanded and containing fluid signal hypointense on T1, hyperintense onT2, with peripheral enhancement of contrast (Fig. 1, 2). It was impinging on the right optic canal and right superior orbital fissure with displacement of cavernous sinus and right ICA. The patient was then referred to Oto-rhino-laryngologists for further management. Diagnostic nasal endoscopy did not reveal any positive findings. CT Scan of the PNS shows the sphenoid sinus to be expanded and completely filled with non enhancing low attenuation material suggestive of mucocele (Fig. 3). Anteriorly the mucocele was seen bulging into right posterior ethmoidal air cells and the right superior and inferior orbital fissure. Right wall of the sphenoid was not visualized and the mucocele was seen bulging into right temporal lobe. Right cavernous sinus was stretched and displaced. The patient underwent FESS and the per-operatively there was a bulge seen in the spheno-ethmoidal recess on the right anterior wall of the sinus which was debrided, gush of purulent material was seen. The sinus was cleared. Wide sphenoidotomy and posterior septectomy was done. Fungal mucin was also seen in the sphenoid sinus. Internal carotid artery and cavernous sinus were displaced posterolaterally. Mucocele was seen eroding the lateral wall of sphenoid sinus and bulging into right temporal lobe. Postoperative period was uneventful and patient is kept on follow up.
Fig. 1, 2.
MRI brain showing the sphenoid sinus to be expanded and containing fluid signal hypointense on T1, hyperintense onT2, with peripheral enhancement of contrast
Fig. 3.
CT Scan of the PNS showing the sphenoid sinus to be expanded and completely filled with non enhancing low attenuation material suggestive of mucocele
Discussion
Mucoceles of the frontal and ethmoid sinuses occur commonly but mucoceles of the sphenoid sinus are very rare and have and incidence of 1% [2]. The exact mechanism of development of a spontaneous mucocele is not clear. It can be caused by obstruction of sinus ostium due to infection, chronic inflammation, allergy, trauma, neoplasm or surgical intervention [4, 5].
Sphenoid sinus mucoceles tend to have varied clinical presentation depending on the direction of expansion toward adjacent structures and the presence of infection. The sphenoid sinus is closely related to cranial nerve 2–6, pituitary gland, superior orbital fissure, optic chiasma, nerve of pterygoid canal, cavernous sinus and internal carotid artery. An enlarging mucocele can cause compression and displacement of these vital structures and if it impinges on optic canal or superior orbital fissure, loss of vision, optic neuropathy, ptosis, ophthalmoplegia and diplopia can occur [6]. Common presenting symptoms a headache, decrease visual acuity, visual loss, visual field defects, nasal symptoms like and anosmia, rhinorrhea, nasal obstruction [7, 8]. Irreversible visual loss due to sphenoid sinus mucocele has been reported after surgical intervention in large mucoceles [5].
The prognosis for recovery in visual disturbance is poor if it is sudden onset and with no light perception preoperatively. Rare cases of sudden bilateral blindness, permanent central diabetes insipidus, erosion of sellar base with endocrine dysfunction have been reported [8–10]. The investigation of choice is generally CT and MRI. Mucoceles can have variable signal intensities on MRI depending on the density, water and protein content and presence of infection and hemorrhage. They usually have low signal intensity, isointense on T1 weighted images and hyperintense on T2 weighted images. CT Scan is always complementary to MRI. Mucoceles do not enhance with contrast but acute inflammation may show enhancement. The Definitive treatment of choice is endonasal endoscopic approach [4, 7]. Endoscopic marsupialization that attempts to exteriorize sphenoid sinus by partial removal of anterior and inferior walls of the mucocele is preferred. In our patients this approach was done along with posterior septectomy. The earlier the intervention the better the improvement of visual symptoms. If patient has already lost the eyesight then the prognosis is poor hence it is imperative to detect this condition early to prevent the development of serious and lifelong complications.
Conclusion
Mucoceles of the sphenoid sinus are a very rare with variable clinical presentation.Imaging place a crucial role in diagnosis and early surgical intervention is vital to avoid complications. Endonasal endoscopic approach is the preferred line of management.
Funding
No funding was used in this study.
Declaration
Conflict of interest
Authors declare that they have no conflict of interest.
Ethics approval
This study was done after taking approval from Ethical committee of the Institution and is compliant with ethical standards.
Footnotes
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Contributor Information
Savita Lasrado, Email: savita_menezes@yahoo.com.
Kuldeep Moras, Email: kuldeepmoras@gmail.com.
Carol Jacob, Email: caroljacob40@gmail.com.
References
- 1.Kosling S, Hintner M, Brandt S, Schulz T, Bloching M. Mucoceles of the sphenoid sinus. Eur J Radiol. 2004;51(1):1–5. doi: 10.1016/j.ejrad.2003.09.002. [DOI] [PubMed] [Google Scholar]
- 2.Akan H, Cihan B, Celenk C. Sphenoid sinus mucocele causing third nerve paralysis: CT and MR findings. DentomaxillofacialRadiol. 2004;33:342–344. doi: 10.1259/dmfr/92903178. [DOI] [PubMed] [Google Scholar]
- 3.Rombaux P, Bertrand B, Eloy P, Collet S, Daele J, Bachert C, et al. Endoscopic endonasal surgery for paranasal sinus mucoceles. Acta Otorhinolaryngol Belg. 2000;54(2):115–122. [PubMed] [Google Scholar]
- 4.Cheng CSM, Sanjay S, Yip CC, YuenH W. Sphenoidalmucocele presenting as acute cranial nerve palsies. Saudi J Ophthalmol. 2012;26(4):459–461. doi: 10.1016/j.sjopt.2012.10.002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Darouassi Y, Righini CA, Reyt E. Mucoceles of the sphenoidal sinus: a report of four cases and review of the literature. B-ENT. 2005;1(1):181–185. [PubMed] [Google Scholar]
- 6.Hejazi N, Witzmann A, Hassler W. Ocular manifestations of sphenoidal mucoceles. Surg Neurol. 2001;56:338–343. doi: 10.1016/S0090-3019(01)00616-4. [DOI] [PubMed] [Google Scholar]
- 7.Garcia JC, Alvarez AMG, Perez IM, Gonzales NG, Gonzales AH, Perez POC. Endoscopic treatment of sphenoid sinus mucocele: case report and surgical considerations. Case Rep Otolaryngol. 2017;1:1–4. doi: 10.1155/2017/7567838. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Devarasetty A, Natarajan K, Begum T, Kumar ARS, Kameswaran M. Sphenoid sinus mucoceles. Int J Otorhinolaryngol Head Neck Surg. 2018;4(4):907–912. doi: 10.18203/issn.2454-5929.ijohns20182700. [DOI] [Google Scholar]
- 9.Casteels I, De Loof E, Brock P, Jorissen M. Sudden blindness in a child: presenting symptom of a sphenoid sinus mucocele. Brit J Ophthalmol. 1992;76:502–504. doi: 10.1136/bjo.76.8.502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Salehi PP, Chithiwala Z, Balough B. Atypical presentation of a sphenoid sinus mucocele: vision loss, partial hypopituitarism, adrenal insufficiency and SIADH. B-ENT. 2017;13:327–334. [Google Scholar]