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Year : 2014  |  Volume : 62  |  Issue : 5  |  Page : 548--549

Giant oculomotor nerve schwannoma presenting as a sellar and suprasellar mass with parasellar extension

Satya Bhusan Senapati, Sudhansu Sekhar Mishra, Srikanta Das, Deepak Kumar Parida 
 Department of Neurosurgery, Shrirama Chandra Bhanja Medical College and Hospital, Cuttack, Odisha, India

Correspondence Address:
Satya Bhusan Senapati
Department of Neurosurgery, Shrirama Chandra Bhanja Medical College and Hospital, Cuttack, Odisha
India




How to cite this article:
Senapati SB, Mishra SS, Das S, Parida DK. Giant oculomotor nerve schwannoma presenting as a sellar and suprasellar mass with parasellar extension.Neurol India 2014;62:548-549


How to cite this URL:
Senapati SB, Mishra SS, Das S, Parida DK. Giant oculomotor nerve schwannoma presenting as a sellar and suprasellar mass with parasellar extension. Neurol India [serial online] 2014 [cited 2020 Jul 9 ];62:548-549
Available from: http://www.neurologyindia.com/text.asp?2014/62/5/548/144459


Full Text

Sir,

Schwannomas account for 7% of all intracranial tumors and commonly arise from the vestibulocochlear and trigeminal nerves. Schwannomas arising from the oculomotor nerve are very rare, except with neurofibromatosis. Approximately 40 cases of oculomotor nerve schwannomas have been described in the literature, of which 12 cases were large (≥2.5cm) [1],[2] tumors. This report presents a case of giant oculomotor nerve schwannoma.

A 24-year-old female complained of progressive diplopia, ptosis of left eye for 2 years. These complaints were overlooked by family members. For the last six months, she had developed gradual progressive visual loss of left eye followed by right eye. She also used to have generalized headache, vomiting and features suggesting hypo-function of pituitary gland. On examination, her visual acuity was figure counting at 1 meter distance in both the eyes with left oculomotor nerve palsy and bilateral optic atrophy. Magnetic resonance imaging (MRI) of brain revealed a large, enhancing mass (6.1 × 3.6 × 6.2 cm) with central necrosis involving sellar and suprasellar regions, extending into left middle cranial fossa [Figure 1] and [Figure 2]. Left pterional craniotomy and wide splitting of the Sylvian fissure for tumor access was carried out. A large encapsulated, white, firm, moderately vascular, multilobulated tumor was found with a necrotic yellowish central zone. Intratumoural decompression, followed by dissection of tumor in arachnoid plane carried out. Though the tumor was abutting internal carotid artery but arachnoid plain was well maintained, so dissecting out the tumor from carotid was easy. After substantial debulking of the mass, the third nerve appeared from the interpeduncular cistern as a bundle and ran straight into the base of the mass. Complete removal of the tumor was done [Figure 3]. Preservation of nerve was tried but could not be preserved and was sacrificed. Postoperatively, the patient developed complete third nerve paralysis on the left side. Histopathology and immunohistochemistry confirmed the diagnosis of schwannoma [Figure 4]. During one year follow-up, her hormonal status had improved without radiological evidence of recurrence.{Figure 1}{Figure 2}{Figure 3}{Figure 4}

Kovacs, [3] who in 1927, described an isolated oculomotor nerve schwannoma observed during an autopsy, was probably the first to report such a tumor. Celli et al[4] divided oculomotor cranial nerve schwannomas into three groups: (1) Cisternal, (2) cisternocavernous and (3) cavernous lesions. This classification was based on the preferred extension of these tumors. Our case belongs to the cisternal type. The explanation for this large tumor could be that the ventral cistern of the brainstem is a potential space where these slow-growing tumors expand to a large size before they produce symptoms. Preserving function of the third nerve in these large tumors can be a challenge (whether complete or partial resections done), as confirmed in previous reports. [5],[6]

References

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