Sphenoid Sinus Mucoceles

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Sphenoid Sinus Mucoceles 1. Neurosurg. / Volume 32 / April, 1970 Sphenoid Sinus Mucoceles G. ROBERT NUGENT, M.D., PHILIP SPRINKLE, M.D., AND BYRON M. BLOOR, M.D. Division o/Neurological Surgery, and Division oJ Otolaryngological Surgery, West Virginia University Medical Center, Morgantown, West Virginia HE neurosurgeon is familiar with the The etiology of a mucocele is conjectural. frontal sinus mucocele as a common It would be convenient to consider them as T cause of unilateral exophthalmos and simple retention cysts of the sinus resulting disorders of eye movement, but the less from inflammatory blockage of the draining common sphenoid sinus mucocele may have ostium. However, they do occur when the escaped his experience. These lesions are po- ostium is patent. Nor does a blocked ostium tentially more serious, and are often misdi- always result in mucoceles. 17,47,61 Others agnosed and operated on as pituitary tu- have considered them as originating from mors. A mucocele of the sphenoid sinus was cystic dilatation of the mucus glands of the first described in 1889 by Berg? Since then epithelial lining of the sinus, or from the there have been sporadic reports, primarily cystic degeneration of contained polyps. 3,17 in the European literature, the best being SchiillerG4 has raised the possibility of the that of Lundgren and Olin. 4~ It is the pur- development of a hypophyseal cyst from cell pose of this paper to review the world litera- rests in the inner or under half of the sella ture, add two additional cases, and alert the turcica, but evidence for this is lacking. The neurosurgeon to a lesion easily mishandled. location of the lesion and the finding of cho- Data on 63 cases have been analyzed as the lesterin crystals in the cyst fluid in 10 cases basis of this report. Nineteen other cases raises the question of whether these cysts have been mentioned but are not included in may represent an unusual form of cranio- the analyses because the clinical information pharyngioma. However, cholesterin crystals was too sparse to be useful. 1,1a,1a,zT,41,~l,62 may be a non-specific finding, and the clini- Three cases were not translated. 2~ Nine cal and pathologic features are not those of a cases are used in this analysis but are not craniopharyngioma. identified in the text. 2,15,32,3~,~,4~,~~ Whatever the cause, there is no exit for If the cyst contents are purulent, pyocele the cyst contents, and the accumulating se- might be the more proper term. Frequently, cretions thin and expand the cavity, ulti- however, the sphenoid sinus mucocele con- mately causing compression of surrounding tains a creamy substance which has the ap- structures. In the case of the sphenoid sinus, pearance of a purulent exudate but is sterile. the adjacent non-bony structures include the One case called a pyocele and two others first six cranial nerves, the carotid arteries, called abscesses all failed to grow pathogens the cavernous sinus, and the pituitary gland. when cultured2 4,67 Because it is difficult to It is the involvement of the cranial nerves determine what is a true pyocele and what is which brings the patient to the physician. In a mucocele,1~ we have included the "pyo- many individuals, there is only a thin papy- celes" in this series. We have also included raceous partition of bone separating the sinus as mucoceles the lesions termed sphenoid from the optic nerve, cavernous sinus, tuber- "cysts.,,~,22,~ culum sella, and medial wall of the superior These lesions frequently involve the poste- orbital fissure and orbit27 Examination of a rior ethmoidal cells and have been called disarticulated skull (Fig. 1) shows how eas- spheno-ethmoidal rnucoceles, 23,~2 but since ily expansion of the sphenoid sinus could en- the symptoms are related primarily to the croach upon these structures. sphenoid area, and the posterior ethmoids are only involved secondarily, we prefer the Case Reports term "sphenoid sinus mucoceles." Case 1. This 33-year-old man was admit- ted on March 20, 1961, because of right Received for publication June 17, 1969. ptosis, severe headache, and limitation of in- Revision received November 11, 1969. ward gaze with the right eye. He had had in- 443 444 G. R. Nugent, P. Sprinkle and B. M. Bloor He was unable to adduct the eye. The diag- nosis of pituitary apoplexy was made. Operation. A left frontal craniotomy was performed. Upon exposing the left optic nerve, a tense midline, dome-shaped mass was seen in the region of the jugum sphenoi- dale, elevating the dura and causing destruc- tion of a large area of bone in the midpor- tion of the posterior frontal fossa. No fluid was obtained on aspiration of the mass. Inci- sion of the mass released a brown mucoid substance. Aspiration disclosed a glistening walled chamber 6 )< 4 cm in the region of the sphenoid sinus. The diagnosis of sphe- noid sinus mucocele was made and the linear dural incision closed with interrupted silk. The cyst contents were described patho- logically as eosinophilic mucous-like mate- Fic. 1. Photograph of interior of sphenoid sinus rial containing filamentous structures, red of normal disarticulated skull. The arrow identifies bloed cells, and neutrophils. Routine, fun- the optic nerve coursing through the upper lateral gus, and acid-fast cultures of the cyst fluid sinus covered by only a thin partition of bone. all failed to grow organisms. Below the nerve the lateral wall of the sinus forms Postoperative course. The next day the the medial wall of the superior orbital fissure. patient's headache was gone, and he could count fingers with his right eye. The visual termittent frontal headaches and periorbital field on the right was full to gross confronta- pain for 11 years, associated with nasal stuffi- ness. During a severe headache 8 years be- fore admission he suddenly became blind in the left eye. Operation on the maxillary sin- uses improved the headache. A year later the diagnosis of glaucoma was made. A year be- fore admission he began having intermittent visual disturbances in the right eye. Examination. There was optic atrophy and no light reflex in the blind left eye. Vi- sual acuity in the right eye was 20/70. There was extensive glaucomatous excava- tion of the left disc, and slight right ptosis. Both eyes were prominent but this was greater on the left. There was no adduction of the left eye. He had a normal sense of smell. Skull x-ray films showed an enlarged sella turcica with erosion of the floor. The posterior clinoids were preserved but the left anterior clinoid was blunted. There appeared to be a pharyngeal mass (Fig. 2). It was felt that the patient had a pituitary tumor, and on April 3 a left carotid arteriogram showed narrowing of the carotid siphon and slight elevation of the first portion of the anterior cerebral artery. The next day his headache Fro. 2. Case 1. Lateral view of skull showing was worse, and vision in his right eye sud- erosion of floor of sella turcica, thinning of dor- denly diminished to light perception only. sum sella and posterior pharyngeal mass. .
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