Choroidal Thickness in Beta-thalassemia Patients

Beta-Thalassemia Clinical Trial

Official title:

Evaluation of Choroidal Thickness in Patients Suffering From Beta-thalassemia

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04067258
• Other study ID #: 9894 / 20 -5 -2016
• Status: Completed
• Start date: May 1, 2019
• Est. completion date: April 1, 2020

Study information

• Verified date: June 2020
• Source: University Hospital of Patras
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The purpose of this study is to examine choroidal thickness in beta-thalassemia patients and compare it to the one of healthy controls.

An equal number of transfusion dependent beta-thalassemic patients and age and sex matched healthy volunteers will undergo spectral-domain optical coherence tomography utilizing the enhanced depth imaging application to visualize and measure the choroid.

Description:

Beta thalassemia is an inherited hemoglobinopathy, associated with defective production of beta-chain globin resulting in problematic HbA production. It is classified according to the severity as minor, intermedia and major. Patients suffering from beta-thalassemia intermedia and beta-thalassemia major require regular blood transfusions. Transfusion related hemosiderosis in these patients necessitates the use of chelating agents to prevent iron overload in vital organs such as the liver and heart.

A number of ocular abnormalities can present in beta-thalassemia patients. Those are categorized as pseudoxanthoma elasticum (PXE)-like changes that include angioid streaks, peau d'orange like fundus and optic nerve head drusen and non-PXE-like changes such as increased venous tortuosity.

Furthermore, it is well established that prolonged treatment with some of the chelating agents such as deferoxamine are associated with ocular toxicity, namely nyctalopia, colour perception anomalies, visual field disturbances, cataract formation, optic neuropathy and pigmentary retinopathy.

The pathophysiology of those ocular manifestations has not been fully clarified. The role of the choroid has not been determined since this particular tissue was previously unaccessible to imaging. Enhanced depth imaging optical coherence tomography is able to image the choroid providing reasonable clarity compared to spectral domain optical coherence tomography.

The aim of this study is to evaluate possible alterations of choroidal thickness in beta thalassemia as compared to healthy controls.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 60
• Est. completion date: April 1, 2020
• Est. primary completion date: March 30, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 85 Years

Eligibility

Inclusion Criteria:

• Beta thalassemia patients undergoing blood transfusions

Exclusion Criteria:

• History of glaucoma, keratoconus, retinal disease, ocular trauma, ocular surgery, uveitis, amblyopia, strabismus, ocular vascular abnormalities

• Spherical refractive error greater than 4 diopters or cylindrical refractive error greater than 2 diopters

• History of other systemic disease such as uncontrolled hypertension, diabetes mellitus, or connective tissue disease.

Related Conditions & MeSH terms

• Beta-Thalassemia
• Thalassemia

Intervention

Diagnostic Test:
• EDI-OCT
EDI-OCT (enhanced depth imaging spectral domain optical coherence tomography) wiil be performed in all study participants. Three sets of measurements in the macular (horizontal and vertical) and peripapillary area will be averaged.

Locations

Country	Name	City	State
Greece	Department of Ophthalmology, General University Hospital of Patras	Patras	Achaea

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital of Patras

Country where clinical trial is conducted

Greece, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Subfoveal choroidal thickness	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted subfoveally	8-10 am
Secondary	Choroidal thickness nasally to the fovea	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted at anatomic locations nasally to the subfoveal point	8-10 am
Secondary	Choroidal thickness inferiorly to the fovea	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted at anatomic locations inferiorly to the subfoveal point	8-10 am
Secondary	Choroidal thickness temporally to the fovea	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted at anatomic locations temporally to the subfoveal point	8-10 am
Secondary	Choroidal thickness superiorly to the fovea	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted at anatomic locations superiorly to the subfoveal point	8-10 am
Secondary	Peripapillary choroidal thickness (inferior, superior, nasal and temporal fields)	Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted at the inferior, superior, nasal and temporal quadrants in the peripapillary area.	8-10 am