Choroidal Thickness in Beta-thalassemia Patients

• ClinicalTrials.gov Identifier: NCT04067258
• Recruitment Status: Completed
• First Posted: August 26, 2019
• Last Update Posted: June 26, 2020
• Sponsor: University Hospital of Patras
• Information provided by (Responsible Party): Constantinos D. Georgakopoulos, MD, PhD, University Hospital of Patras

Tracking Information

• First Submitted Date: August 21, 2019
• First Posted Date: August 26, 2019
• Last Update Posted Date: June 26, 2020
• Actual Study Start Date: May 1, 2019
• Actual Primary Completion Date: March 30, 2020 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: August 21, 2019)

Subfoveal choroidal thickness [ Time Frame: 8-10 am ]

Manual measurements of the choroid starting from the end of the retinal pigment epithelium throughout the outline of the sclera, will be conducted subfoveally

• Original Primary Outcome Measures: Same as current

Current Secondary Outcome Measures (submitted: August 21, 2019)

• Choroidal thickness nasally to the fovea [ Time Frame: 8-10 am ]
  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
• Choroidal thickness inferiorly to the fovea [ Time Frame: 8-10 am ]
  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
• Choroidal thickness temporally to the fovea [ Time Frame: 8-10 am ]
  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
• Choroidal thickness superiorly to the fovea [ Time Frame: 8-10 am ]
  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
• Peripapillary choroidal thickness (inferior, superior, nasal and temporal fields) [ Time Frame: 8-10 am ]
  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.

• Original Secondary Outcome Measures: Same as current
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Choroidal Thickness in Beta-thalassemia Patients
• Official Title: Evaluation of Choroidal Thickness in Patients Suffering From Beta-thalassemia

Brief 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.

Detailed 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.

• Study Type: Observational
• Study Design: Observational Model: Other; Time Perspective: Prospective
• Target Follow-Up Duration: Not Provided
• Biospecimen: Not Provided
• Sampling Method: Probability Sample

Study Population

Patients with beta-thalassemia major or intermedia undergoing blood transfusions will be examined utilizing EDI-OCT.

A group of equal healthy volunteers will also be included to serve as controls.

• Condition: Beta-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.

Study Groups/Cohorts

• Beta-Thalassemia group
  Patients suffering from beta thalassemia major or intermedia will be included in this group
  Intervention: Diagnostic Test: EDI-OCT
• Control group
  Healthy age and sex matched volunteers will be included in this group
  Intervention: Diagnostic Test: EDI-OCT

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: June 24, 2020): 60
• Original Estimated Enrollment (submitted: August 21, 2019): 50
• Actual Study Completion Date: April 1, 2020
• Actual Primary Completion Date: March 30, 2020 (Final data collection date for primary outcome measure)

Eligibility Criteria

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.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years to 85 Years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: Greece

Administrative Information

• NCT Number: NCT04067258
• Other Study ID Numbers: 9894 / 20 -5 -2016
• Has Data Monitoring Committee: No

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

• IPD Sharing Statement: Not Provided
• Current Responsible Party: Constantinos D. Georgakopoulos, MD, PhD, University Hospital of Patras
• Original Responsible Party: Constantinos D. Georgakopoulos, MD, PhD, University Hospital of Patras, Assistant Professor in Ophthalmology
• Current Study Sponsor: University Hospital of Patras
• Original Study Sponsor: Same as current
• Collaborators: Not Provided
• Investigators: Not Provided
• PRS Account: University Hospital of Patras
• Verification Date: June 2020