Combined retinal pigment epithelial (RPE) and retinal hamartomas are focal, usually solitary malformations composed of overgrowth of mature glial, vascular and pigmented cells.12 Any prior reports documenting more than one hamartoma in an eye were not found on a MEDLINE search. We report a rare case of twin hamartomas in the same eye and their unique optical coherence tomographic (OCT) findings.
An eight-year-old female child was referred to the vitreoretina service of our tertiary eye care hospital for evaluation of asymptomatic pigmented lesions in the fundus of the right eye. Ocular examination revealed a best corrected visual acuity of 20/20 with normal anterior segments in both eyes. The fundus of the left eye was normal. Indirect ophthalmoscopy of the right eye revealed two lesions. The first lesion was a well-defined, slightly elevated, predominantly pigmented, peripapillary lesion about 0.89 mm in diameter [Fig. 1A]. Another grayish lesion measuring 0.56 x 7.29 mm in size was noted in the inferonasal mid-periphery with overlying tortuous vessels and collaterals [Fig. 1B]. The OCT ((STRATUS OCT™ Model 3000, Carl Zeiss Meditech technologies) of the peripapillary lesion demonstrated full thickness replacement of the retinal layers by a highly reflective material [Fig. 1C]. The OCT of the inferonasal tumor showed highly reflective material in both the inner and outer retinal layers at the level of the RPE [Fig. 1D].
On fundus fluorescein angiography, the peripapillary lesion demonstrated central hypofluorescence with peripheral staining [Fig. 2A]. In the late phases, the inferonasal lesion demonstrated leakage from the overlying tortuous vessels and collaterals [Fig. 2B]. Based on the above findings that were commensurate with the diagnostic criteria put forward by Gass,1 a diagnosis of twin combined hamartoma of the retina and RPE was made.
Combined pigment epithelial and retinal hamartomas are usually solitary and unilateral. There is only a mention by Gass in his discussion on the paper by Schachat et al., of two combined hamartomas in one eye in a series of 35 eyes.3 However, we are unaware of any previous publications demonstrating the same (Medline search).
Shields et al. have reported disorganization of retinal architecture on OCT of combined hamartomas.4 Ting et al. have described hyper-reflective mass lesions with hyporeflective shadowing of the underlying tissues.5 The OCT findings of the tumors in our case do not concur with these previous reports and were also different from each other. The OCT findings of the inferonasal mass of highly reflective material in both the inner and outer retinal layers could point towards hamartomatous tissue at these levels, with a preservation of the middle retinal layers. The peripapillary lesion showed a full thickness replacement of the retinal layers by a highly reflective material, which could be melanin, considering its pigmented nature. This possibly reflects a predominance of pigmented cells in the peripapillary tumor whereas vascular (reflected by the telangiectasia) and probably glial elements in the inferonasal tumor.
In conclusion, this case report documents the fact that combined hamartomas may be multiple in the same eye with differing admixture of glial, vascular and pigmented cells in each tumor as demonstrated by OCT.
1. Gass JD. An unusual hamartoma of the pigment epithelium and retina simulating choroidal melanoma and retinoblastoma Trans Am Ophthalmol Soc. 1973;71:175–85
2. Font RL, Moura RA, Shetlar DJ, Martinez JA, McPherson AR. Combined hamartoma of sensory retina and retinal pigment epithelium Retina. 1989;9:302–11
3. Schachat AP, Shields JA, Fine SL, Sanborn GE, Weingeist TA, Valenzuela RE, et al Combined hamartomas of the retina and retinal pigment epithelium Ophthalmology. 1984;91:1609–15
4. Shields CL, Materin MA, Shields JA. Review of optical coherence tomography
for intraocular tumours Curr Opin Ophthalmol. 2005;16:141–54
5. Ting DT, Mccuen BW 2nd, Fekrat S. Combined hamartoma of the retina and retinal pigment epithelium Retina. 2002;22:98–101