Choroidal Abnormalities in Pediatric NF1: A Cohort Natural History Study

SIMPLE SUMMARY: Choroidal abnormalities (CAs) have recently been introduced as one of the criteria for the diagnosis of neurofibromatosis type 1 (NF1). The aim of the present study was to assess the natural history of CAs in a large pediatric population affected by NF1, evaluating, on a long-term follow-up, CAs progression both in number and dimensions. To avoid bias due to the growing process of the eye, the CAs dimensions were normalized for the optic disc size. Our study demonstrated, in 99 eyes of 53 pediatric patients, an increase in the number, area and perimeter of CAs. The present study thus provides evidence that, in NF1 pediatric patients, CAs change with time, increasing both in number and dimensions, independently from the physiological growth of the eye. While the increase of the CAs number occurs particularly at an earlier age, the increase in the CAs dimensions is a slow process that remains constant during childhood. ABSTRACT: The purpose of this study was to assess the long-term natural history of choroidal abnormalities (CAs) in a large pediatric neurofibromatosis type 1 (NF1) population, quantifying their progression in number and dimensions. Pediatric patients (<16 years old) affected by NF1 with a minimum follow-up of 3 years with at least one CA in one eye were consecutively recruited. Near-infrared (NIR) imaging was performed to identify CAs, which were quantified in number and size. The CAs area and perimeter were normalized for the optic disc dimensions to avoid possible bias related to the growing process of the eye. Ninety-nine eyes of 53 patients were evaluated. The CAs number, area and perimeter significantly increased during follow-up (p < 0.0001 for each parameter). The patient age at baseline was inversely correlated with the CAs number over time (coefficient = −0.1313, p = 0.0068), while no correlation was found between the patient age and CAs progression in size. In conclusion, we provide evidence that, in NF1 pediatric patients, CAs change over time, increasing both in number and dimensions, independently from the physiological growth of the eye. While the increase of the CAs number occurs particularly at an earlier age, the increase in the CAs dimensions is a slow process that remains constant during childhood.