Bilateral Congenital Ptosis Associated with Optic Disc Melanocytoma.

We report a rare clinical association of optic disc melanocytoma (ODM) occurring with bilateral congenital ptosis that has not been previously reported. A 28-year-old male patient presented with bilateral congenital ptosis. On examination, his vision was 20/20 in each eye, and dilated fundus examination indicated a pigmented lesion over the left inferior temporal aspect of the optic disc that was consistent with an optic nerve melanocytoma. B-scan ultrasonography indicated a calcified elevated optic nerve head. Bilateral frontalis sling procedures were performed for congenital ptosis with satisfactory results at 1 year postoperatively. There was no progression of the lesion in the left eye. Knowing the key ophthalmoscopic features of an ODM can aid in diagnosing this lesion; ophthalmologists should be familiar with this lesion in addition to the rare association of ptosis. Affected patients should be periodically assessed. Copyright:

Introduction

Melanocytoma of the optic disc was first described by Zimmermann, as a benign hamartoma arising from melanocytes.[1] It is a rare deep-pigmented pathology that affects partial or whole optic nerve with characteristic connection with neighboring retina and choroid.[2] Melanocytoma was perplexed with melanoma of the choroid. However, in 1962, Zimmerman and Garron explained its benign nature and phrased the term melanocytoma.[3] Histologically, melanocytoma represents an accumulation of pigmented cells with abundant cytoplasm, small nuclei, and normal nucleoli, which are features of a benign lesion.[3] In the present report, we describe a rare clinical association of bilateral ptosis with optic disc melanocytoma (ODM) which, to the best of our knowledge, is the first of its kind in the English peer-reviewed literature. Consent was taken from the patient to publish the identifiable photographs. This report follows the tenets of the Declaration of Helsinki.

Case Report

A 28-year-old male presented with bilateral drooping of the upper eyelids [Figure 1] since birth and blurry vision in the left eye for the last 2 years. There was no previous history of trauma, surgery, or any ophthalmic disorder. Systemic history was positive for cervical disc herniation as secondary to his compensatory head position to overcome the bilateral ptosis. The remainder of his medical history was noncontributory. On ophthalmic examination, his vision was 20/20 in each eye; intraocular pressure measured with applanation tonometry was within the normal range bilaterally. The patient had bilateral ptosis and full extra-ocular motilities in all gazes with no restriction or pain upon movement. The pupils were symmetrical with no afferent defect and color vision was unremarkable. There was no ocular melanocytosis bilaterally. Slit-lamp biomicroscopy was unremarkable bilaterally. Dilated fundus examination indicated a pigmented lesion over the inferior temporal part of the left optic disc that was compatible with an ODM [Figure 2a]. The right fundus was unremarkable. B-scan ultrasonography of the left eye indicated a hyperreflective calcified lesion that was the characteristic of melanocytoma [Figure 2b]. Observation of the lesion was recommended. Bilateral frontalis sling procedure was performed for the congenital ptosis for the reason that the patient had neck pain and cervical disc herniation secondary to the abnormal head-up position, with satisfactory results at 1 year of follow-up. The lesion in the left eye did not progress.

Figure 1

External photograph of the face showing bilateral ptosis

Figure 2

(a) Fundus photograph of the left eye demonstrating inferior temporal location melanocytoma, partial involvement of the disc with poorly defined margins; (b) B-scan ultrasonography of the left eye showing high internal reflectivity and calcification at the disc margin

Discussion

ODM is a benign hamartoma that is usually asymptomatic and remains stable in size. It rarely affects the optic disc and the most common location is inferior temporal to the disc margin.[4]

The current case is an uncommon presentation of ODM associated or could be a concurrent finding with congenital ptosis as it was never reported in the literature to have ptosis as a finding in a patient with ODM. Over time, melanocytoma may lead to local compressive sequelae such as branch retinal artery occlusion or venous[1] and ischemic optic neuropathy.[5] Rare malignant transformation may occur in 1%–2% of the cases, with a progressive increase in size and extensive involvement of the disc.[1] ODM may develop spontaneous necrosis and induce central retinal vascular obstruction characterized by rapid sight deprivation.[6] Rai et al. have described an unusual association of ODM and normal tension glaucoma.[7]

Generally, ODM, in general, has no systemic disease association. Two reports had found associated intracranial meningioma[8] and pituitary adenoma.[9] A previously published case series reported an association of ODM with systemic hypertension due to high catecholamine.[10] The tendency of ODM to present in a unilateral fashion as in our presented case. However, Demirci et al. demonstrated the rare presentation of bilateral lesions and often evident in the pediatric age group, indicating a congenital probability.[11]

In the current case, there were no changes in visual acuity, ODM size did not change, and malignant transformation has not occurred to date. Shields et al. demonstrated Kaplan–Meier estimates (KME) of the lesion growth and decrease in the vision of two Snellen lines or more of 38% and 33%, respectively, at 20 years.[1] However, Lee et al.[5] reported the KME of the lesion growth of 14% at 5 years.[12] ODM was considered a malignant lesion with a poor prognosis; it is nowadays recognized as a benign tumor with a favorable prognosis. Our patient showed no features of progression through all clinical examination visits. We encourage ophthalmologists to carefully look for associated ptosis with ODM, as it may leave cosmetic or/and functional disabilities to these patients; moreover, annual evaluation is needed to detect any changes in the textural, size, and the morphological appearance of the ODM.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.