Combined hamartoma of the retina and retinal pigment epithelium: A case report

BACKGROUND: Combined hamartoma of the retina and retinal pigment epithelium (CHRRPE) is a rare congenital benign tumor which is commonly monocular. Typical CHRRPE comprises slightly raised lesions at the posterior pole, with proliferation membrane often leading to vascular distortion. In severe cases, macular edema, macular hole, retinal detachment or vitreous hemorrhage may occur. Patients with atypical clinical manifestations are prone to misdiagnosis by inexperienced ophthalmologists. CASE SUMMARY: A 33-year-old man reported onset of right eye blurred vision for one week prior. Anterior segment and intraocular pressure were normal in both eyes. Left eye fundus photography was normal. Right eye ophthalmoscopy showed vitreous hemorrhage and off-white raised retinal lesions below the optic disc. Proliferative membranes on the lesion surfaces resulted in superficial retinal detachment and tortuosity and occlusion of peripheral blood vessels. A horseshoe-like tear in the temporal periphery was surrounded by retinal detachment. Optical coherence tomography revealed retinal thickening at the focal site with structural disturbance indicated by high reflectance. Right eye ultrasound showed retinal thickening at the lesion, stretching and uplifting of the proliferative membrane, with moderately patchy echo at the optic disc edge. Cytokines and antibodies were detected in vitreous fluids during the operation to rule out other diseases. Fundus fluorescein angiography (FFA) at postoperative follow-up led to final diagnosis of CHRRPE. CONCLUSION: FFA is helpful in diagnosing retinal and retinal pigment epithelial combined hamartoma. In addition, other cytokine and etiological tests facilitate further differential diagnosis to rule out other suspected diseases.