Early Detection of CHRPE and Subsequent Familial Adenomatous Polyposis Syndrome by Ultra-Wide Field Retinal Laser Scanning Technology

Abstract

Introduction: Congenital hypertrophy of the retinal pigment epithelium (CHRPE) has been associated with familial adenomatous polyposis (FAP) and may be the first presenting feature of the disease process. This case presents the diagnosis of CHRPE by ultra-wide field retinal laser scanning technology. A 68-year-old male who was seen in the outpatient ophthalmologic care setting for post-op follow-up 1 month after photorefractive keratectomy (PRK) of OU in both eyes and correction of retinal detachment (RD) of the (OS) left eye. This patient has also previously tolerated phacoemulsification (PE) and intraocular lens placement (IOL), with open capsule for a cataract and Lasik surgery of OU without complication. Patient came in with complaints of his distance vision not being as clear as before the RD. Near is closer in the OS than before. Post-op follow up included ultra-wide field retinal laser scanning that reveal an OS peripheral CHRPE, and vitelliform dystrophy. We recommended IOL and referred the patient to oncology and gastrotroenterology, where he was diagnosed and treated as a new incident case of FAP. The most common and very first extracolonic manifestation is CHRPE, with reports of expression in 36-90% of FAP kindred, and with a specificity of 95% for being a carrier of the APC tumor suppressor gene deletion that leads to FAP. This tumor suppressor gene was identified at the long arm of chromosome 5 (5q21). Guidelines using older technology recommended that patients with more than 3 CHRPE in 1 eye or bilateral CHRPE, as well as patients with a positive family history and 1 unilateral CHRPE require further gastroenterological evaluation. In the future, the use of ultra-wide field retinal laser technology may detect CHRPE earlier than standard diagnostics, and subsequently lead to timely care for FAP.Figure 1