Multimodal imaging characteristics of congenital grouped hyper- and hypo-pigmented fundus lesions

The imaging characteristics of congenital grouped pigmentation of the retinal pigment epithelium (CGP-RPE) and its non-pigmented variant - grouped congenital albinotic retinal pigment epithelial spots (GCARPES) are poorly defined in the literature. Our case series reports their multimodal imaging characteristics across a spectrum of presentations.

A retrospective review of patient records was conducted on patients seen at the Centre for Eye Health between January and December 2016. The multimodal imaging findings across four cases is described using optical coherence tomography (OCT), infrared imaging, ultra-widefield imaging, fundus photography and fundus autofluorescence (FAF).

Case 1 is a 55-year-old female with a bilateral presentation of CGP-RPE showing typical features. Case 2 is a 28-year-old male with a classical presentation of GCARPES in the left eye. Case 3 is a 33-year-old female with unilateral CGP-RPE and an atypical solitary congenital hypertrophy of the retinal pigment epithelium (CHRPE) in the same eye. Case 4 is a unilateral presentation in an 11-year-old female with unusual characteristics. Ocular imaging characteristics of CGP-RPE lesions varied between patients: OCT showed visible RPE changes in cases 3 and 4 but not case 1. The pattern of FAF and infrared imaging also varied with most lesions displaying a pattern of hypo-autofluorescence, but some central lesions in case 3 exhibited hyper-autofluorescence. All lesions were visible with fundus photography.

FAF can be helpful in alerting clinicians to the presence of lesions that may be difficult to visualise funduscopically and OCT can be helpful in differentiating between CGP-RPE and its variants from more sinister ocular conditions. All in all, these findings highlight the variable manifestation of CGP-RPE and its variants on multimodal imaging; the diagnosis of CGP-RPE and its variants should remain based on its characteristic funduscopic appearance.