Retinal Changes in Vitamin D Deficiency

Study Overview
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Brief Summary
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Retinal tissue parameters of pediatric patients with vitamin D deficiency will be evaluated in this prospective case-control study. The patients will be divided into 2 groups according to the vitamin D level. Retinal vessel diameters, retinal nerve fiber evaluation, choroidal thickness will be evaluated. Choroidal thinning decrease in retinal artery diameter and increase in retinal vein diameter will be detected in the vitamin D deficiency group.

Detailed Description
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The study of the relationship between vitamin D status and retinal diseases is a new concept, and there is a large gap in research focusing on the pediatric population in the literature. The importance of vitamin D in retinal maturation and its role in the development of retinal diseases at a young age is being investigated. In this sense, as far as known, it is the first study investigating retinal structure parameters in pediatric patients with vitamin D deficiency.

Official Title
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Evaluation of Retinal Structure in Pediatric Subjects With Vitamin D Deficiency

Conditions
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Pediatric Disorder, Vitamin D Deficiency, Retinal Disease, Choroidal Disease, Optic Nerve Diseases

Intervention / Treatment
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* Dietary Supplement: Vitamin D deficiency


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria:(Group 1): age <18 years old serum vitamin D [(25(OH) D), calcitriol] level <20 ngr/mL in previous two weeks visual acuity >20/20 manifest refraction spherical equivalent <3D normal biomicroscopic and fundus examination. Exclusion Criteria: history of any chronic ocular diseases, except for refractive error (e.g., uveitis, glaucoma, retinopathy of prematurity) history of ocular surgery (e.g., cataract, strabismus, open globe injury, laser photocoagulation) having an ocular abnormality (e.g., persistent fetal vasculature, optic disc hypoplasia, fovea plana) history of systemic diseases that have the potential to affect ocular tissues (e.g., diabetes mellitus, Graves' disease, albinism, Down syndrome, Fabry diseases, Wilson syndrome) history of any systemic diseases that can affect the serum vitamin D level (e.g., parathormone or calcium metabolism disorders) already receiving vitamin D treatment.

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Group 1: 1) age <18 years old; 2) serum vitamin D [(25(OH) D), calcitriol] level <20 ngr/mL in previous two weeks Group 2: 1) age <18 years old; 2) serum vitamin D [(25(OH) D), calcitriol] level >20 ngr/mL in previous two weeks
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Pediatric endocrinologist<br>Patient selection by pediatric endocrinologist on the basis of vitamin D | Dietary Supplement: Vitamin D deficiency<br>* Ocular significance of vitamin D deficiency in pediatric cases<br>|
| No Intervention: Ophthalmologist<br>Evaluation of the results by 2 different retina specialists during the examination of patients Interpretation of the results without knowing the vitamin D level of patients | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| choroidal thickness | subfoveal, and subfoveal 1500-µm- and 3000-µm-diameter distance nasal and temporal areas | up to 3 months | 
| retinal nerve fiber layer | Retinal nerve fiber layer will be detected by optical coherence tomography | up to 3 months | 
| The central retinal artery and vein calibers | The central retinal artery and vein calibers will be analyzed with the Interactive Vessel Analyzer | up to 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood vitamin D levels | vitamin D deficiency or normal effects of vitamin D deficiency | up to 3 months |