Endoscopic sinus surgery for Fronto-ethmoid mucocelewith orbital extension

Bozena B Wrobel, M.D.

A 64-year female presented with 5 years history of headaches, chronic left orbital pain, swelling of the left upper lid and medial canthal region, diplopia, left ptosis, chronic nasal obstruction and postnasal drainage. For the past four years, the patient had been followed by numerous ophthalmologists who prescribed corrective lenses for her progressing diplopia. She also had left facial and orbital pain and required use of a narcotic (fentanyl) patch. The past medical history was significant for endoscopic sinus surgery 10 years ago, an emergency hospitalization for severe left facial and orbital pain with acute sinusitis and periorbital cellulitis six months ago, trigeminal neuralgia and allergic rhinitis.

The clinical examination revealed downward and lateral displacement of the left eye, left ptosis, decreased ocular mobility on upper gaze, and increased diplopia on extreme lateral gaze. The visual acuity was 20/200 on the left and 20/20 on the right. On nasal endoscopy partially resected and lateralized middle turbinates were visualized. The complete obstruction and severe scarring of frontal recess on the left were present.

A CT scan of the paranasal sinuses (Figure 1, 2) revealed three mucoceles on the left: fronto-ethmoid mucocele with orbital extension, a lateral frontal mucocele with orbital extension and sphenoid mucocele. The left frontal sinus was expanded. There was erosion of the superior aspect of the lamina papyracea, lacrimal bone and roof of the orbit. The left eye was displaced infero-laterally. Additional imaging studies were available from the referring physician: a contrast MR of the head which confirmed the presence of the multiple mucoceles and a normal MRA performed to rule-out a vascular lesion (carotid aneurysm) as the cause of the left ptosis.

An endoscopic transnasal marsupialization approach to the mucoceles was planned. Due to the lateral extension of the frontal mucocele, an endoscopic modified Lothrop procedure was also discussed with the patient. For localization during surgery, a stereotactic computer assisted surgical navigation system was utilized. A left endoscopic maxillary antrostomy, complete ethmoidectomy, and sphenoidotomy with evacuation of the sphenoid mucocele were performed first. Scarring between the remnant of the middle turbinate and lateral nasal wall was removed, and the fronto-ethmoid mucocele was entered. The axillary flap technique 1 was used for the direct access to the frontal recess. The retained, partially eroded, anterior ethmoid cells (bulla and ager nasi cells) were resected. The frontal ostium was noted to be enlarged by the disease process. Intrasinus septal cell was opened. To improve exposure to the lateral frontal mucocele, the nasal beak was thinned out with an angulated diamond drill. The lateral frontal mucocele was visualized with the 45 and 70 degree scopes. Using the angulated instruments the mucocele was evacuated and the thin layer of bone separating the mucocele from the rest of the frontal sinus was removed. The dehiscent orbital roof with intact periorbita was visualized. Marsupialization and complete evacuation of the mucoceles was achieved.

Patient was hospitalized overnight for the pain control issues considering preoperative dependency on narcotics. Postoperatively the patient's facial and orbital pain diminished and use of the fentanyl patch was discontinued. On follow-up exam she had full motility of the left eye, and the visual acuity was 20/20 bilateral. The hypoglobus (downward displacement of the eye) substantially improved with only occasional complaints of diplopia. Follow-up CT scan (3 months post-op) has shown complete evacuation of the mucoceles with well aerated frontal sinuses (Figure 3, 4). Follow-up nasal endoscopy (4 months post-op) revealed well-mucosalized and widely patent frontal recess and frontal sinus (Figure 5, 6).

Discussion:

Mucoceles are an epithelial lined mucus-containing benign lesions originating in the paranasal sinuses. Scarring of a sinus ostium is the most common cause of mucocele formation and it can be secondary to previous surgery, trauma, repeated infections or fibrosis 2. Mucoceles usually enlarged slowly causing an expansion of the sinus, and gradual thinning of the bony margins, frequently with local bone erosion and extension to the orbit or intracranial space. Rapid expansion of the mucoceles might occur following sinus infection. Mechanisms of expansion of the mucoceles are still debated. It has been suggested that the direct positive pressure within the mucocele is responsible for the mucocele expansion3. Another mechanism postulates that bone resorption factors (prostaglandin, interleukin 1 and tumor necrosis factor) in the interface between the bone and the mucocele result in a destructive bone resoption and expansion of the mucoceles 4.

Mucoceles most commonly arise in the frontal and anterior ethmoid sinuses and rarely in the sphenoid and maxillary sinuses. The fronto-ethmoid mucoceles usually present with orbital symptoms of infero-lateral eye displacement, lid edema, swelling in the supero-nasal and medial canthal region, diplopia, proptosis, ptosis, palpable mass, reduced vision, orbital pain and headache. With a long standing fronto-ethmoid mucocele the diplopia might be minimal Sphenoid mucoceles can present with compressive optic neuropathy, exophtalmos, diplopia, ocular muscle paresis, retroorbital pain and headache. Since the orbital manifestations are the most common mode of presentation, patients with ethmoid, fronto-ethmoid and sphenoid mucoceles are frequently first evaluated by an ophthalmologists. Maxillary mucoceles usually present with facial pain and swelling, and rarely with orbital extension. Orbital extension in a maxillary mucoceles may cause enophtalmos secondary to the bone erosion of the orbital floor, or an upward eye displacement.

CT scan of the paranasal sinuses is the most definitive imaging study to localize the extent and pathology of the mucocele. It demonstrates expanded sinus with thinning and frequently erosion of the sinus bone. The contrast MR imaging is helpful in differentiating mucoceles from sinonasal tumors. Mucoceles shown thin peripheral linear enhancement with central low signal intensity on T1-weighted images while tumors demonstrate diffuse enhancement 5.

Traditionally, in the past, paranasal sinus mucoceles were treated with complete removal of the sinus mucosal lining and obliteration of the sinus. The obliterative procedures generally involve greater surgical morbidity and difficulties in postoperative radiographic imaging of the sinuses. Over last decade the endoscopic surgery with transnasal marsupialization and drainage of mucoceles has become widely accepted as a definitive treatment 6, 7, 8, 9. Numerous authors shown excellent results with the endoscopic marsupialization procedures 9, 10, 11, 12. The endoscopic procedures are reported with a lower mucocele recurrence rate 0.9%- 9% 2, 11 compared to a 19% recurrence rate 10, 13 for osteoplastic flap and obliteration procedures.

In general, the surgical treatment of a fronto-ethmoid mucocele with intraorbital or intracranial extension by an obliterative technique should be avoided, whenever possible. These mucoceles frequently have significant bone erosion and adherence to the dura or orbital periosteum. Since obliterative technique requires removal of the entire mucosal lining to prevent the recurrence, attempt of stripping the mucosa can result in injury to the dura with a CSF leak or injury to the orbit 10, 12. If external approach is utilized for access, concept of endoscopic marsupialization of the mucocele to the nasal cavity, should still be maintained. Complex fronto-ethmoid mucoceles with bone erosion and intracranial or orbital extension can be successfully treated with endoscopic marsupialization. The removal of the entire mucocele lining is not necessary to achieve a cure for these paranasal sinus mucoceles as long as the opening between the mucocele and the nasal cavity remains patent. Post marsupialization the mucocele lining retains the ability to regenerate normal respiratory epithelium 14.

In cases of laterally located frontal mucoceles or complicated frontal mucoceles, with significant bony separation from the nasal cavity, a modified endoscopic Lothrop (MEL) is an effective alternative to external approaches12, 15. MEL procedure provides an excellent access to the frontal sinuses and insures adequate drainage and wide opening of the mucoceles.

Patients with mucoceles require long term follow-up since recurrence of mucoceles may occur even years after the surgery.

In the case presented above, marsupialization and the drainage of the multiple mucoceles, including the more laterally located frontal mucocele, was successful through an endoscopic approach. The stereotactic computer assisted surgical navigation system was helpful as a confirmatory tool for localization of the lateral mucocele during surgery. The patient had complete resolution of orbital and facial pain, and has significant improvement of most of her orbital symptoms. The patient declined any further corrective surgery with her oculoplastic surgeon for the residual hypoglobus. Long-term follow-up will be necessary to monitor for any recurrences of her mucoceles. In this patient, endoscopic transillumination of the frontal sinus post-op can be reliably used as a simple procedure to document patency of the frontal sinus (Figure 7) and monitor for recurrences.


Figure 1


Figure 2


Figure 3


Figure 4



References:
  1. Wormald PJ. The axillary flap approach to the frontal recess. Laryngoscope 2002, 112: 494-99
  2. Conboy PJ, Jones NS. The place for endoscopic sinus surgery in the treatment of
  3. paranasal sinus mucoceles. Clin Otolaryngol 2003; 28: 207-10
  4. Kass ES, Fabian RL, Montgomery WW. Manometric study of paranasal sinus
  5. mucoceles. Ann Otol Rhinol Laryngol 1999; 108: 63-66
  6. Lund VJ, Henderson B, Song Y. Involvement of cytokines and vascular adhesion
  7. receptors in the pathology of fronto-ethmoidal mucoceles. Acta Otolaryngol 1993; 113:540-546
  8. Lanzieri CF, Shah M, Krauss D, et al: Use of gadolinium-enhanced MR imaging for differentiating mucoceles from neoplasms in the paranasal sinuses. Radiology 1991; 178:425-428.
  9. Lund VJ. Endoscopic management of paranasal sinus mucoceles. J Laryngol Otol
  10. 1998; 112: 36-40
  11. Kennedy DW, Josephson JS, Zinreich SJ, et al. Endoscopic sinus surgery for the
  12. mucoceles: a viable alternative. Laryngoscope 1989 Sep 99(9): 885-95
  13. Schaefer SD, Close LG. Endoscopic management of frontal sinus disease.
  14. Laryngoscope 1990; 100: 155-60
  15. Har- El G. Transnasal endoscopic management of frontal mucoceles. Otolaryngol Clin North Am 2001; 34: 243-51
  16. Har-El G, Balwally AN, Lucente FE. Sinus mucoceles: is marsupialization enough? Otolaryngol Head and Neck Surg 1997; 117: 633-40
  17. Har El G. Endoscopic management of 108 sinus mucoceles. Laryngoscope 2001;
  18. 111: 2131-4
  19. Khong JJ, Maltora R, Wormald PJ, Selva D. Endoscopic sinus surgery for paranasal sinus mucocele with orbital involvement. Eye 2004; 00: 1-5
  20. Bordley JE, Bosley WR. Mucoceles of the frontal sinus: causes and treatment. Ann Otol Rhinol Laryngol 1973; 82: 696-702
  21. Lund VJ. Fronto-ethmoidal mucoceles. A histopathological analysis. J Laryngol Otol 1991; 105: 921-23
  22. Khong JJ, Maltora R, Selva D, Wormald PJ. Efficacy of endoscopic sinus surgery for paranasal sinus mucocele including modified endoscopic Lothrop procedure for frontal sinus mucocele. J Laryngol Otol 2004, 118: 352-356




ARS e-Survey
The ARS is interested in the views of the users of its website so that future revisions of the website may better serve the needs of its users.
Please rate this article!
Not helpful
Helpful
 1  2  3  4  5
 
© 2008 American Rhinologic Society
All Rights Reserved
Designed and Hosted by Wildfire Internet