Presented at the Meeting of the American Rhinologic Society, Palm Beach, Florida, May 10, 1998.
Objectives To review experience with sphenoid marsupialization and describe the technique using new instrumentation.
Study Design Retrospective review of five cases of chronic sphenoid sinusitis that were resistant to standard medical and surgical methods, which were treated by sphenoid marsupialization.
Methods Charts were reviewed and patients were interviewed regarding postoperative resolution of symptoms.
Results Five cases of recalcitrant sphenoid sinusitis were reviewed. All patients had headache before surgery, and two had visual disturbance. In follow-up ranging from 1 to 87 months, all were free of symptoms related to the sphenoid sinus.
Conclusions Marsupialization is an effective method of exteriorizing a chronically infected sphenoid sinus. The use of functional endoscopic sinus surgery instruments and the TAC attachment of the Midas Rex drill make this surgery possible.
In patients with chronic sinusitis, the most uncommonly afflicted sinus is the sphenoid. The sphenoid sinus is positioned near the geographical center of the head. Its walls are intimately associated with a number of vital structures. When this sinus becomes infected, the thin lateral walls provide scant protection against the spread of inflammation beyond its boundaries. The dura of the middle cranial fossa is adherent to the intracranial side of the bone at the lateral extremities of the sinus. This dura encases the cavernous sinus through which run the internal carotid artery; the third, fourth, and sixth cranial nerves that subserve extraocular muscular function; and all three branches of the trigeminal nerve. In the most superior aspect the optic nerve leaves the orbit and traverses the most superior part of the lateral sinus wall to join its fellow on the opposite side as the optic chiasm. The chiasm sits on the roof of the sphenoid sinus, often indenting it, and lies just anterior to the sella turcica.
Symptoms of sphenoid sinusitis, in addition to the usual complaints that are characteristic of sinusitis (nasal obstruction, foul nasal drainage, and malaise), also include headache, which is usually occipital or parietal and even temporal in location. Diplopia, scotoma, and failing vision are the next most common symptoms of sphenoid sinusitis. Meningitis is not uncommon, and cavernous sinus thrombophlebitis can occur.
Treatment is by the institution of the appropriate antibiotic, often accompanied by antihistamine and decongestant medication. Most patients with acute cases get well; only a few cases become chronic.
There is a certain subset of patients with chronic sinusitis that is highly refractory to most forms of therapy. Many of these patients have a concomitant allergic diathesis that is not controlled by desensitization or antihistamines, and some have Sempter's triad of salicylate sensitivity, nasal polyposis, and asthma. Another group of patients appears to have no specific discernible predisposing factor. Many patients have allergic symptomatology but have negative findings on radioallergosorbent and allergy tests. A group of these patients may possess an unknown, non–immunoglobulin E–mediated hypersensitivity to an element or group of elements in their environment.
Among the patients who have chronic recalcitrant sinusitis are a group who have chronic sphenoid sinusitis. These patients have intermittent foul drainage and periodic headache, especially in the occipital or parietal area and also, often, behind one or both eyes. One of the most debilitating and frightening symptoms is that of diminished visual acuity.
The basic principle of sinus surgery, whether endoscopic or traditional, is to provide adequate drainage or, as in some of the traditional operations, sinus obliteration or ablation. In both methods of surgery the surgical management of ethmoid disease has been by exenteration and marsupialization of the ethmoid block. Surgical treatment of the sphenoid sinus has been directed at creating a large ostium that will allow drainage into the sphenoethmoidal recess. However, two sequelae occur in refractory cases. One is the marked stenosis or atresia of the surgically created, enlarged ostium in the sphenoid rostrum; the second is the high placement of the ostium requiring healthy ciliary action of the mucosa to carry the mucus blanket up and out of the sinus cavity. The described procedure eliminates these stumbling blocks by means of total marsupialization of the sphenoid cavity.
MATERIALS AND METHODS
The surgery is performed under general anesthesia. Mucosal shrinkage is effected by cocaine pledgets placed against the sphenopalatine and anterior ethmoidal neurovascular bundles. One percent lidocaine with 1:100,000 epinephrine is injected into the mucosa of the sphenoid rostrum. The 0° endonasal telescope is placed into the nasal cavity, and residual disease in the ethmoid bloc is removed by the usual functional endoscopic techniques. It is usually necessary to infracture the middle turbinate to provide adequate working room.
The mucosa and underlying bone over the anterior face of the sphenoidal sinus are removed with the resection forceps. Care is taken to address judiciously the sphenopalatine artery as it crosses the anterior sphenoid face. The vessel is cauterized, when visualized, before transection. Pus is suctioned from the opened sphenoid cavity, and all polypoid and diseased tissue is carefully removed.
The final stage is the marsupialization of the sinus. This involves the following steps: 1) creation of a nasopharyngeal mucoperiosteal flap and 2) the removal of the bone of the sphenoid sinus floor. The flap is constructed by cutting the mucoperiosteum with a sickle knife. The long-handled, bayonet-mounted sickle knife provides a strong instrument of sufficient length to nicely accomplish this task. The cuts are made in the lateral recesses of the nasopharyngeal roof extending from the edge of the sphenoid face excision to a point in the roof that marks the posterior termination of the sphenoidal sinus (Fig. 1). The mucoperiosteum of the remaining anterior face of the sphenoid sinus and its floor, which is also the anterior roof of the nasopharynx, is elevated with the long-handled, bayonet-mounted elevator (Fig. 2).
The exposed bone is removed with the Midas Rex TAC 125 attachment with its 2.5-mm match-head bur (Midas Rex, LP, Fort Worth, TX) (Fig. 3). The high speed of the bur (100,000 rpm) and its small head size, coupled with the curve of the tube, provide excellent visualization and rapid removal of bone. The use of the EndoScrub (Xomed Surgical Products, Jacksonville, FL) or similar type of suction irrigation cleansing system is vital to maintain visualization during drilling. The bone of the sphenoid floor is drilled until it is flush with the posterior wall of the sinus, providing no pocket in which pus may loculate centrally.
The mucoperiosteal flap from the inferior sphenoid rostrum and anterior nasopharyngeal roof is turned into the marsupialized cavity and packed in place (Fig. 4). Appropriate splints are placed in the nasal cavities when indicated, and the nose packed for 24 to 48 hours. The nasal pack should be separate from the small sphenoid pack, the latter of which is removed at 3 to 5 days.
From 1991 to 1998 five patients were operated on using the technique described in “Materials and Methods.” Patient data are summarized in Table I. Most of the patients were women. Patient age ranged from 37 to 77 years, and the average age was 60 years. Before surgery all patients complained of a headache as their primary symptom. The pain was usually occipital or retro-orbital. Two patients complained of diminished visual acuity. There were no instances of diplopia. After surgery the headache and visual symptoms disappeared in all patients. One patient, however, had return of mild pain and blurred vision that cleared on suctioning of a crust over the sinus opening. She has been symptom free for 2 years at the time of writing. There were no complications. Although all of the sphenoidal sinuses remained marsupialized and open, all had some cicatrization of soft tissue around the edges.
Table Table 1.. Summary of Patient Data.
The sphenoid sinus is the least likely sinus to be afflicted with chronic infection. This is most fortunate because of the numerous physiologically vital structures adjacent to its roof and lateral walls. Complications of permanent diplopia, blindness, meningitis, carotid artery aneurysm formation or necrosis, and even death may occur (Cheesman A, Personal communication, February 1998). Because of its anatomical location, the sinus is difficult to approach. In addition to the standard intranasal approach, transseptal and transpalatal approaches have been developed.
The greatest impediment to establishing a permanent enlargement of the sphenoid sinus ostium is a natural cicatricial atresia of the opening following surgery. The cicatrix, no doubt, results from recurrent ongoing infection of the chronically diseased mucosa in the exenterated ethmoid, coupled with the inflammatory component of the refractory allergic response so commonly encountered in this group of patients. Sphenoid sinus marsupialization is an attempt to totally exteriorize the sphenoid sinus cavity by both removing the entire anterior sinus wall and excising the floor which is in common with the nasopharyngeal roof. Total marsupialization in some sphenoid sinuses is precluded by the sinuses' lateral pneumatization into the lesser wing. The lateral floor of the sinus will be the body of the sphenoid from which the pterygoid plates subtend. This impediment to complete marsupialization will provide a minimal opportunity for the loculization of infection.
The coupling of the development of functional endoscopic sinus surgery and the availability of instrumentation developed for skull base surgery has provided the opportunity to perform surgical procedures on the sphenoidal sinus which were very difficult to perform in the past. The greatest innovation in this regard is the TAC attachment to the Midas Rex drill system. Visualization of the rotating bur head is afforded by virtue of the offset drill handle and the narrow, curved, nonrotating tube that carries the ultrathin shaft of the bur. The TAC attachment can be introduced through the same side of the nose as the endoscope, to directly observe the drilling. The rapid speed of the bur under direct vision provides for rapid, safe, and accurate bone removal.
The turning in of the mucoperiosteal bone flap composed of sphenoid rostral and anterior nasopharyngeal roof will obliterate the posterior extremity of the sinus, reducing the cavity to a mucosa-lined pocket.
Because chronic sphenoid sinusitis is rare, the number of patients in the series is small. They are a subset of the patients who have refractory sinusitis. It is clear that this procedure does not eliminate recurrent sinusitis in this cohort of patients. However, the headache and visual disturbances have been ameliorated. The exception is the one patient in whom an obstructing crust developed against the posterior sinus wall, behind which a small amount of pus loculated. Removal of the crust, suctioning of the pus, and antibiotic therapy resulted in a quick restoration of normal vision.
Sphenoid marsupialization is an effective means of ameliorating chronic sphenoidal sinusitis for that unusual cohort of patients in whom adequate allergy control, repeated antibiotic therapy, and thoroughly performed functional endoscopic sinus surgery cannot control the disease.