CHOPXE - Analysis of Choriocapillaris Flow Deficits in Patients With Pseudoxanthoma Elasticum
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Mean percentage of choriocapillary flow deficits by OCT-A on 6x6 mm scans
研究概览
简要总结
This observational study sets out to compare choriocapillaris flow deficits between healthy control subjects and patients with pseudoxanthoma elasticum. Pseudoxanthoma elasticum (PXE) is a rare, incurable hereditary disease caused by genetic mutations. The condition is characterised by excessive tissue mineralisation, which can result in a range of dermatological, vascular, and ophthalmological complications. Among these complications is the potential for visual impairment. The management of this condition is focused on the treatment of its complications. Degeneration of the retina and the choroid (the layer responsible for ensuring its vascularisation) occurs in the eye, resulting in premature degeneration. We would like to study the premature alteration of these structures, which could subsequently be used as an objective marker of the evolution of pseudoxanthoma elasticum.
详细描述
CHOPXE is a single-center, cas-control, cross-sectional study with the objective of comparing choriocapillaris flow deficits by OCT angiography (OCT-A) between healthy control subjects and patients with pseudoxanthoma elasticum.
Study rationale Pseudoxanthoma elasticum (PXE) is a rare disorder, affecting between 1 in 25,000 and 1 in 100,000 people. This autosomal recessive disorder is caused by mutations in the ABCC6 gene. Mutations in the ABCC6 gene have been demonstrated to impair cellular efflux of ATP, which is ordinarily converted to inorganic pyrophosphate (PPi) and adenosine. PPi is a potent endogenous inhibitor of calcification, while adenosine contributes indirectly to calcification inhibition by suppressing the synthesis of tissue-nonspecific alkaline phosphatase (TNAP).
The disease has been shown to cause ectopic mineralization and fragmentation of tissue elastic fibres.
- The initial indications of the disease manifesting in the skin are frequently observed in childhood or adolescence. These initial signs evolve slowly and unpredictably, as evidenced by the appearance of papular skin lesions in flexural zones.
- The ophthalmological manifestations (peau d'orange, angioid striae, sub-retinal neovascularization, optic nerve drusen) may be responsible for visual impairment through central blindness.
- The presence of vascular manifestations, including peripheral arterial disease, gastrointestinal bleeding and ischaemic stroke, has been identified as a contributing factor to the premature mortality observed in patients with PXE, when compared to the general population.
Angers University Hospital is a national rare diseases reference center for PXE, with an active file of nearly 300 patients.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •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
排除标准
- •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
研究组 & 干预措施
Healthy volunteers arm with opthtalmologic evaluation
干预措施: Opthtalmologic diagnosis tests (Diagnostic Test)
结局指标
主要结局
Mean percentage of choriocapillary flow deficits by OCT-A on 6x6 mm scans
时间窗: Inclusion
Comparison of macular choriocapillaris flow deficits per OCT angiography (OCT-A) between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage
次要结局
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A per age, over 6x6mm ;(during inclusion visit)
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A per ETDRS grid sub-sector ;(During inclusion visit)
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of inflammatory skin lesion in PXE patients ;(During inclusion visit)
- Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of arterial stenosis of the lower limbs(During inclusion visit)
- Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of carotid artery dysplasia(During inclusion visit)
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A per ETDRS grid sub-sector ;(During inclusion visit)
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A per age, over 6x6mm ;(during inclusion visit)
- comparison between healthy controls and patients with pseudoxanthoma elasticum in pre-atrophic stage : - Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of inflammatory skin lesion in PXE patients ;(During inclusion visit)
- Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of arterial stenosis of the lower limbs(During inclusion visit)
- Average percentage of choriocapillaris flow deficits per OCT-A according to the presence of carotid artery dysplasia(During inclusion visit)