Oculomotor Disturbances Due to Granular Cell Tumor

Abstract

Primary granular cell tumor of the orbit is a rare type of neoplasm. The tumor is frequently associated with extraocular muscles, and eye motility limitation is an unavoidable complication after its surgical removal. The objective of the present article is to review the literature on primary granular cell tumors of the orbit and to report a case of this uncommon neoplasia. Granular cell tumor is a benign lesion encountered in most cases (58.3%) in the inferior aspect of the orbit. Extraocular muscle involvement occurs in 72.2% of the patients, and diplopia is present in 77.1% of the cases. The inferior and medial recti are the most affected muscles (38.5% and 26.9%, respectively). Surgical excision is the only modality of treatment, but diplopia persists in 73.3% of the cases. In conclusion, granular cell tumor is a benign lesion but involves a high rate of extraocular muscle morbidity.

Orbital granular cell tumours: clinical and pathologic characteristics of six cases and literature review

“…Consistent with a previous report, 27 we witnessed no recurrence following complete surgical removal. While McNab et al 14 once reported that many tumours with incomplete excision also exhibited no recurrence, in our cases (and in our review of the literature) 37.5% of benign GCTs with subtotal resection demonstrated tumour recurrence.…”

“…The fact that neural-derived GCT is closely associated with EOMs may be due to the dense neural supply of EOMs. 27 Vision decrease/loss due to tumour adhesion to the ON was noted in 32.5% of cases in our study. Strangely, the ON is thought to be an outgrowth of the central nervous system (CNS), which does not possess Schwann cells.…”

“…It is a remarkable fact that, in cases in the literature review that involved EOMs, complete excision of the tumour did not provide optimal prognosis for motility in the majority (73.3%) of cases. 27 Similarly, in cases involving the ON, surgery cannot improve the patient's vision. The possibility of tumour infiltration into the ON should remind ophthalmologists to perform a comprehensive evaluation of the surgical results, and to inform patients properly.…”

Granular Cell Tumor Located in the Bulbar Subconjunctival Space

“…In ocular adnexa, GCT has been reported to occur in the orbit, extraocular muscles, caruncule, eyelid skin, palpebral conjunctiva, and lacrimal drainage apparatus [5,6,7,8,9,10,11,12]. In our literature search, no clear report of GCT isolated in the bulbar subconjunctival space was found.…”

“…Although it has been reported to affect many structures of the ocular adnexa, including the palpebral conjunctiva, we found no single case located at the subconjunctival bulbar space [5,6,7,8,9,10,11,12]. …”