NCT04153344

Function of the Pigment Epithelium in Patients With Type 1 Neurofibromatosis

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 30 (actual)
• Sponsor: Assistance Publique - Hôpitaux de Paris · Academic / Other
• Sex: All
• Age: 7 Years
• Healthy volunteers: Not accepted

Summary

The objective of this study is to study the function of the pigment epithelium in patients with neurofibromatosis type 1 using electro-oculogram to confirm abnormally high values reported in previous studies, but also to correlate this hyperactivity of the pigment epithelium with the presence and size of choroidal hyperreflective areas observed in infra-red imaging of the fundus. The hypothesis of the study is that the function of the pigment epithelium measured by the electro-oculogram correlates with the surface of choroidal hyperreflective areas. Finally, the potential consequences of a supra-normal function of the pigment epithelium on the global retinal function are not known. A full-field electroretinogram will evaluate the global neurosensory retinal function.

Detailed description

Patients with neurofibromatosis type 1 have numerous eye problems: glioma of the optic pathways, Lisch nodules, palpebral involvement by plexiform neurofibromas, orbital dysplasia, etc. With the emergence of multimodal imaging in ophthalmology a new ocular involvement has been described: choroidal hyperreflective areas. They are located in the most superficial layers of the choroid, adjacent to the retinal pigment epithelium, visible only on infra-red imaging of the fundus. These areas are frequently observed, about 90% in adults and 70 to 80% in children. With a sensitivity of 0.83 and a specificity of 0.96, these lesions would have their place as a diagnostic criterion for neurofibromatosis type 1. In parallel, two successive studies have evaluated the function of the retinal pigment epithelium using electro-oculograms; they showed in patients with neurofibromatosis type 1 a significant increase in the Arden ratio, reflecting hyperactivity of the pigment epithelium. The objective of this study is to study the function of the pigment epithelium in patients with neurofibromatosis type 1, using electro-oculogram to confirm these abnormally high values, but also to correlate this hyperactivity of the pigment epithelium to the presence and total area of choroidal lesions observed in infra-red imaging of the fundus. The hypothesis of the study is that the function of the pigment epithelium measured by the electro-oculogram correlates with the surface of the choroidal hyperreflective areas. Finally, the potential consequences of a supra-normal function of the pigment epithelium on the global retinal function are not known. A full-field electroretinogram will evaluate the global neurosensory retinal function.

Conditions

• Neurofibromatosis Type 1

Interventions

Type	Name	Description
OTHER	Electro-oculogram	Electrophysiological recording of changes in electrical potential across the retinal pigmentary epithelium during successive periods of dark and light adaptation, according to ISCEV standards. Results will comprise dark trough value and light/dark (Arden) ratio.
OTHER	Full-field electroretinogram	Electrophysiological recording of retinal function. Results will comprise amplitudes and latencies of each electroretinography response (dark-adapted 0.01, dark-adapted 3.0, dark-adapted 10.0, dark-adapted 3.0 oscillatory potentials, light-adapted 3.0, light-adapted 3.0 flicker).

Timeline

• Start date: 2020-05-11
• Primary completion: 2020-07-21
• Completion: 2020-07-21
• First posted: 2019-11-06
• Last updated: 2025-09-12

Locations

1 site across 1 country: France