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CASE REPORT |
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Year : 1989 | Volume
: 37
| Issue : 4 | Page : 194-195 |
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Primary intraorbital meningioma and schwannoma-A rare association
Subash C Sharma, RC Ray, MI Hassan
Command Pathology Laboratory, P.O. Dilkhusha, Lucknow-226 002, India
Correspondence Address: Subash C Sharma Command Pathology Laboratory, P.O. Dilkhusha, Lucknow-226 002 India
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 2638311 
Primary intraorbital meningioma and Schwannoma are rare tumours. For them to occur concurrently, or one following soon after another should be considered a curiosity. We present a 40 year old male who reported with proptosis of the right eye and a meningioma was removed surgically. Within 3 months symptoms recurred and a schwannoma was removed at surgery from the same site. Interesting features of the lesion are presented and discussed.
How to cite this article: Sharma SC, Ray R C, Hassan M I. Primary intraorbital meningioma and schwannoma-A rare association. Indian J Ophthalmol 1989;37:194-5 |
Introduction | |  |
Orbit is a rare site for the development of a meningioma. Cushing and Eisenhardt [1] could find only one example in their series of 313 cases. Schwannomas in the orbit are also rare and comprise only 1 % of the orbital tumours [2],[3]. Most of these tumours when detected singly occur in females and often in the first and second decade. We present a 40 year old male from whom a meningioma was removed from the right orbit and three months later a Schwannoma was removed from the same site. Unusual features of the case and continued paucity of literature prompted this report. The available relevant literature is reviewed briefly.
Case report | |  |
A 40 year old male presented with a two year history of headaches and slowly progressive protrusion of the right eye. During the previous six months the proptosis had increased more rapidly. The patient had complained of double vision. Results of systemic examination were normal. No nodes were felt in the head or neck. Visual acuity was 20/20 in each eye. Extra ocular movements were full. The right eye was displaced forward and temporally. Eyelid fissures were equal, with no eyelid lag or retraction. Intraocular pressure was 16 mm Hg in each eye. Results of ophthalmoscopy were normal with no cupping. The sensations of the right cheek (inferior orbital nerve) was slightly decreased. Supraorbital and corneal sensations were normal. Thyroid studies showed no dysfunction.
Computed tomography showed a mass in the right orbit, 2 x 2.5 cm in size, which did not enhance. It was located adjacent to the optic nerve and medial rectus muscle and it appeared to be separated from the optic nerve. Because of lack of enhancement, the diagnosis of hemangioma was considered unlikely. The possibility of myosities was considered.
The diagnostic ultrasound examination showed orbital tumour located within the muscle cone, bordering and merging with optic nerve superiorly and nasally. The mass was 25 mm in width with the well-outlined posterior border 31 mm from the external eyelid surface in the supra nasal quadrant.
Within the mass, cystic spaces were noted. The mass had a hard to firm (slightly compressible) consisitency and indented the globe slightly.
The orbital mass was removed through a superior orbitotomy. It was ovoid in shape measuring 3.8 x 2.2 x 1.9 cm, with a smooth bright yellow surface and patchy brown discolouration. Whorling with few cysts filled with brown fluid were present on the cut surface.'Microscopically it showed whorl formation, groups of round to polygonal cells with indistinct outline and vescicular nuclei [Figure - 1].
Intervening cells were spindle shaped. An occasional psammoma body was present. A diagnosis of primary orbital meningioma was made. The immediate post-operative period was uneventful. Pain and proptosis reappeared three months later. Local examination and investigations suggested recurrence of the lesion. A possible diagnosis of glioma was considered. The orbital mass was removed. It was a light brown partially encapsulated firm mass measuring 2.2 x 1.8 x 1.2 cm with few cystic spaces filled with brown fluid. Microscopically it revealed typical features of a schwannoma showing Antony A and Antony type B features [Figure - 2]. The first mass removed in Jan 1987 was reviewed and more sections taken to specifically exclude schwannoma differentiation in a meningioma.
Discussion | |  |
Meningioma and Schwannoma can occur wherever meningothelial cells and Schwann cells are present. Both are rare tumours in the orbit and for them to occur concurrently or one following another must be considered a curiosity. This is, however, theoratically possible as both are histogenetically ectodermal in origin'. In the present case it is difficult to conclude whether it is one tumour with dual differentiation or two separate tumours presenting separately on two occasions. The latter is a stronger possibility. It is likely that both were present concurrently and that the Schwannoma, was too small at first surgery and missed. It is also possible that it grew rapidly after removal of meningioma, as more space was made available for its expansion.
Orbital meningioma may arise from the meningeal sheath accompanying the optic nerve. The region of the optic foramen is the common site, and cases have been recognised in which the lesion was bilateral [1]sub . But more often it grows as a spindle shaped mass about the nerve immediately,anterior to the foramen. In distinction from the optic nerve glioma, the sheath meningiomas tend to perforate the outer dura and hence invade the orbital contents.
Schwannoma (neurilemoma) on the other hand, is a neoplasm that can occur where ever schwann cells are present, that is, in any myelinated peripheral nerve. In the orbit, Schwannomas originate from the sensory nerves, tend to occur during middle age, are located behind the globe, grow slowly and may be painful. The tumour, often, begins focally in a nerve and enlarges in a nodular fashion to become an encapsulated mass covered by stretched perineural cells. It maybe indepeddent or associated with neurofibromatosis. However, neurofibromas of the orbit are not encapsulated. There was no evidence of neurofibromatosis in this patient[5].
References | |  |
1. | Cushing H. and Eisenhardt L. The meningioma. Thomas Springfield, Illinois, pp 51-63,1938. |
2. | Konrad EA and Thiel H J. Schwannoma of the orbit. Ophthalmologica. 118 -120,1984. |
3. | Footman J, Goldberg C, Robertson W. Primary orbital Schwannomas. Br J Ophthalmol. 66:194-199.1982. |
4. | Byrne SR, and Glaser. Orbital tissue differentiation with standardized echography. Ophthalmology. 90:1071-1073 1983. |
5. | Frazier-Byrne S, and Byrne BM. Differential diagnosis of orbital Schwannoma with standardized echography. In Ossoing KC (ed) : Ophthalmic Echography. Dordrecht, Nijhoff/Junk, pp 483-492. 1987. |
[Figure - 1], [Figure - 2]
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