In the left eye the fundus fluorescein angiography features and spectral domain optical coherence tomography findings were compatible with a congenital simple hamartoma of retinal pigment epithelium (CSHRPE) at fovea. It is essential to detect this tumour and differentiate it from other pigmented retinal lesions.
Congenital simple hamartoma of the RPE was first recognized by Laqua  in 1981. Gass  coined the term retinal hamartoma in 1989. Since then, very few cases are reported in the literature [3-4].
The largest case series has been reported by Shields et al. in 2003 and included 5 cases . We report ophthalmoscopic and imaging findings (FFA, OCT, B Scan) of a case with CSHRPE at fovea.
Fundus fluorescein angiography (FFA), optical coherence tomography (OCT) and ocular B Scan ultrasonography were performed. Fluorescein angiography showed blockage of fluorescence during all phases of FFA due to pigmented tumour and there was no leakage at fovea [Figure 2a & 2b]. The retinal vessels at macula were minimally dilated and there was no feeder vessels for the tumour mass. The temporal arcades were dragged towards the lesion.
The macular OCT scan was performed using CirrusTM HDOCT Model 4000 (Carl-Zeiss Meditec, Inc, Dublin, California, USA). The High definition OCT image scan - HD 5-line raster scan [Figure 3] of the left eye revealed an abruptly elevated hyper reflective mass with increased optical reflectivity on its inner surface with optical shadowing beneath and well-defined clear cut tumour margins. There was vitreo macular adhesion at the nasal margin of the lesion. The surrounding retina and choroid was normal. The retinal tumour thickness in SD-OCT was 1004 microns (1 mm). B-scan ocular ultrasonography of the left eye showed a nodular high-echogenic small mass at the macula [Figure 4].
Congenital SHRPE was described by Laqua  in 1981, based on clinical observations in 2 cases. He reported a 39 year old man with decreased vision who had a jet-black parafoveal tumour of 1 mm basal dimension that projected through full thickness retina into the vitreous cavity, minimally dilated feeding vessels were noted. This lesion remained stable for 15 years.
The second case was a 15 year old boy with good visual acuity and a 0.5 mm black full thickness retinal tumour inferior to the foveola. He pointed out that these lesions differed from CSHRPE and other RPE lesions. In 1989, Gass  published a review on focal congenital anomalies of the RPE and he coined the term RPE hamartoma. In 2003, Shields  documented the largest case series consisting of 5 patients. The OCT findings of CSHRPE were first described by Shields et al. in 2004. Then Shukla et al  reported that OCT is a useful, non-invasive tool for the diagnosis of this rare tumour. In 2014, A.C. Barnes et al  reported a case of CSHRPE with foveal involvement and secondary epiretinal membrane formation that underwent surgical excision allowing for a detailed histopathological examination of the lesion that showed a nodular proliferation of hyperplastic RPE cells with attached gliotic retina and internal limiting membrane (ILM). The RPE cells showed fibrous metaplasia. CSHRPE is an uncommon presumed congenital lesion that has characteristic ophthalmoscopic, fluroescein angiographic and OCT features. CSHRPE appears ophthalmoscopically as a small localized, elevated black lesion adjacent to fovea. It is usually < 1 mm in diameter. The lesions generally remains stationary and is not known to grow . The visual prognosis is good especially for lesions located extrafoveally . This lesion involving a full thickness retina may be associated with retinal traction, retinal exudation, dilated feeding and draining retinal vessels and pigmented vitreous cells [5-9]. None of these associated findings was present in our case.
Fluorescein angiography of CSHRPE showed non fluorescence throughout the angiogram and in the late phase a subtle silhouette of mild hyperfluorescence was noted, lining the temporal edge of the mass that was reported by Shields et al  similar findings was seen in our case.
Ocular B-scan ultrasonography demonstrates an echogenic, nodular, small mass in the retina-choroid region with moderate to high internal reflectivity on A scan and without shadowing [4-5]. Similar B scan findings was seen in our case. Cirrus HD Spectral domain OCT macular cube 512 x 128 scan protocol and HD OCT image scan of our case showed an elevated retina at the site of the lesion, increased optical reflectivity on its inner surface, optical shadowing of deeper structures and clearly cut tumour margins.
The surrounding retina and choroid had normal structures. These Oct findings were consistent with those of previously reported cases [4, 7,10,11]. The normal appearance of the adjacent underlying choriocapillaries and choroid in OCT was considered helpful in excluding the diagnosis of choroidal nevus or melanoma . Thus OCT is quite diagnostic in determining the exact anatomical location of the hyperplastic RPE cells located within the retina having their apex at the vitreo retinal surface. To summarize CSHRPE located extrafoveally usually requires no active treatment since the lesion is non progressive and does not affect visual acuity. While CSHRPE located at fovea results in poor visual acuity and the foveal location of the tumour limits the use of laser photocoagulation or other methods of treatment.
Yet it is important to follow-up these patients over long term to rule out tumour growth and suspicious malignant features. Varied pigmented lesions such as congenital hypertrophy of the RPE, combined hamartoma of the retina and RPE, reactive RPE hyperplasia, choroidal melanoma, choroidal nevus, RPE adenoma and adenocarcinoma of the RPE, intraretinal foreign body and melanocytoma should be considered in the differential diagnosis of CSHRPE [4, 5,7-11]. All these can be ruled out by history, clinical examination, fluorescein angiography and other complementary examination.
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