ABSTRACT

Hamartomas are local malformation of cells that demonstrate abnormal proliferation in the area where they are normally present. Retinal and optic disc hamartomas include astrocytic hamartoma, congenital hypertrophy of the retinal pigment epithelium (CHRPE), simple congenital hamartoma of the retinal pigment epithelium (CSHRPE), combined hamartoma of the retina and retinal pigment epithelium (CHRRPE), retinal hemangioblastoma (retinal capillary hemangioma), and retinal cavernous hemangioma. Retinal and optic disc hamartomas can be observed sporadically as well as with systemic associations. Astrocytic hamartoma usually appears as a flat, transparent yellowish lesion. CHRPE is a round, pigmented, and flat lesion. CSHRPE usually presents as a dark black macular tumor. CHRRPE consists of vascular, glial, and pigment epithelial components, which can demonstrate peripapillary, macular, and peripheral localization. Retinal hemangioblastoma is a vascular tumor, red-pink in color with tortuous and dilated afferent and efferent vessels, typically located in the peripheral retina or optic disc. Retinal cavernous hemangioma is characterized by the formation of thin-walled saccular angiomatous structures in the retina or optic nerve head resembling concord grapes. Ultrasonography, fundus autofluorescence, optical coherence tomography, optical coherence tomography angiography, and fluorescein angiography methods are used in the diagnosis of retinal and optic disc hamartomas. Some retinal and optic disc hamartomas do not require treatment. However, complications including vitreous hemorrhage, macular exudation, retinal detachment, macular hole, epiretinal membrane, and choroidal neovascularization require treatment.

Introduction

The term hamartoma is derived from the Greek word “hamartia,” meaning error. Hamartomas are malformations formed by the abnormal proliferation of cells in the region where they are normally found.¹ Unlike neoplasms, which are caused by mutation in a single cell, multiple cells are affected in hamartomas. They are benign, slow-growing lesions that resemble normal tissue, but malignant transformation may occur. Hamartomas are usually associated with a genetic syndrome. They can occur in different parts of the body.¹ Most cases are asymptomatic and are detected incidentally during evaluation for other medical conditions.²

Retinal and optic disc hamartomas include astrocytic hamartoma, congenital hypertrophy of the retinal pigment epithelium (CHRPE), congenital simple hamartoma of the retinal pigment epithelium (CSHRPE), combined hamartoma of the retina and retinal pigment epithelium (CHRPE), retinal hemangioblastoma (retinal capillary hemangioma), and retinal cavernous hemangioma. Retinal and optic disc hamartomas can be observed sporadically or with systemic associations (Table 1). Possible syndromic associations include tuberous sclerosis complex (TSC), neurofibromatosis type 1, retinitis pigmentosa, Usher syndrome, and Stargardt disease for astrocytic hamartoma; familial adenomatous polyposis (FAP) syndrome for CHRPE; neurofibromatosis types 1 and 2, Gorlin-Goltz syndrome, Poland anomaly, and branchio-oculo-facial syndrome for CHRRPE; Von Hippel-Lindau (VHL) syndrome for retinal hemangioblastoma; and cerebral and dermal hemangiomas for retinal cavernous hemangioma.^3,4,5,6,7

There has been no previous publication reviewing retinal and optic disc hamartomas in the literature. Our aim in this article was to collectively examine rare retinal and optic disc hamartomas.

Conclusions

Hamartomas of the retina and optic disc include astrocytic hamartoma arising from glial cells; CHRPE, CSHRPE, and CHRRPE arising from the RPE and retina; and the vascular tumors retinal hemangioblastoma and retinal cavernous hemangioma. Most of these lesions are asymptomatic and detected incidentally in patients presenting for routine eye examination. Macular lesions may cause findings such as reduced visual acuity and visual field loss.

Retinal and optic disc hamartomas may be isolated or associated with systemic diseases As they may be the initial sign of systemic diseases, the ophthalmologist must know the syndrome/diseases associated with these hamartomas.

Most retinal and optic disc hamartomas do not require treatment but should be monitored periodically. While they are generally benign and slow-growing lesions, malignant transformation can occur in rare cases. Treatment can be provided for complications secondary to the tumors.