CHOPXE - Analysis of Choriocapillaris Flow Deficits in Patients With Pseudoxanthoma Elasticum

Launched by UNIVERSITY HOSPITAL, ANGERS · May 27, 2025

Keywords

ClinConnect Summary

The CHOPXE clinical trial is studying a condition called pseudoxanthoma elasticum (PXE), which is a rare genetic disorder that can affect the skin and eyes, potentially leading to vision problems. This study aims to compare blood flow in a specific layer of the eye (called the choriocapillaris) between healthy individuals and those with PXE. By understanding how this blood flow is affected in PXE patients, researchers hope to find ways to track the progression of the disease and better manage its complications.

To participate in this study, you need to be an adult who is either healthy or diagnosed with PXE but not experiencing severe eye problems. Healthy participants must be similar in age and gender to patients with PXE. If you decide to take part, you’ll undergo some eye tests to check your eye health. It’s important to know that certain factors, like having other eye diseases or severe vision issues, could prevent you from joining. This research could play a crucial role in improving care for people with PXE, helping to advance our understanding of this rare condition.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Participant not afflicted by the disease under investigation and without ophthalmological pathology
• • Person matched in age (+/- 5 years) and gender to a case (patient with PXE in pre-atrophic stages included in the PXE cohort)
• • Signature of informed consent for participation in the protocol
• • Adult at time of inclusion Criteria for non-inclusion of research subjects
• • Known ophthalmological diseases (maculopathy, glaucoma, optic neuropathy, retinopathy whatever the aetiology)
• • Known severe myopia, defined by a sphere \> - 6 dioptres
• • Diabetic subject
• • Unable to carry out the ophthalmological examinations of the study
• • Pregnant, breast-feeding or parturient woman
• • Person undergoing psychiatric care under constraint
• • Person subject to a legal protection measure
• • Person not affiliated or not benefiting from a social security scheme
• Exclusion Criteria:
• • Ophthalmic pathology (maculopathy, glaucoma, optic neuropathy, retinopathy, whatever the etiology) discovered during the ophthalmic workup
• • AngioOCT examination inexploitable (artifact and/or image quality less than 50/100 even after pupillary dilation)
• • Severe myopia (sphere \> - 6 dioptres) discovered during the ophthalmic workup.
• Case inclusion critera :
• • Patient diagnosed with pseudoxanthoma elasticum, defined according to Plomp's criteria: two out of three features related to PXE: (1) two pathogenic mutations in the ABCC6 gene, and/or (2) disease-specific dermatological changes and/or (3) disease-specific ocular changes;
• • Included in the PXE cohort ;
• • With pre-atrophic damage, i.e. at least one eye without choroidal neovessels on OCT-A, without previous intravitreal injection of anti-VEGF, and without major retinal atrophy (less than 2 papillary diameters);
• • who have had an angiographic OCT (performed during follow-up consultations) with usable results (no artifacts and image quality of 50/100 or better) ;
• • patient's non-objection to participation in a study
• Case criteria for non-inclusion :
• • Other known ophthalmological pathology (maculopathy, glaucoma, optic neuropathy, retinopathy of any etiology)
• • Severe myopia, defined by a sphere \> - 6 dioptres
• • Diabetic subject