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Changes in Amblyopia Using Optical Coherence Tomography

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ClinicalTrials.gov Identifier: NCT04092361
Recruitment Status : Not yet recruiting
First Posted : September 17, 2019
Last Update Posted : January 27, 2021
Sponsor:
Information provided by (Responsible Party):
Alyaa mohamed yousef ahmed elkabsh, Assiut University

Tracking Information
First Submitted Date September 7, 2019
First Posted Date September 17, 2019
Last Update Posted Date January 27, 2021
Estimated Study Start Date February 1, 2021
Estimated Primary Completion Date October 1, 2021   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures
 (submitted: September 13, 2019)
To measure retinal layers and macular thickness changes in cases of unilateral amblyopia using optical coherence tomography in comparison with the other sound eye. [ Time Frame: from october 1st 2019 to october 1st 2020 ]
Foveal thickness (mean thickness in the central 1000-μm diameter area) and central foveal thickness (mean thickness at the point of intersection of 6 radial scans) are 212 ± 20 and 182 ± 23 μm, respectively. Macular thickness measurements were thinnest at the center of the fovea, thickest within 3-mm diameter of the center, and diminished toward the periphery of the macula. The temporal quadrant was thinner than the nasal quadrant.
Original Primary Outcome Measures Same as current
Change History
Current Secondary Outcome Measures Not Provided
Original Secondary Outcome Measures Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title Changes in Amblyopia Using Optical Coherence Tomography
Official Title Macular and Retinal Changes in Unilateral Amblyopia Using Optical Coherence Tomography
Brief Summary There have been multiple trials to investigate the morphological changes in the macula and retinal nerve fiber layer of amblyopic eyes, due to the different published results and the lack of evident association between these changes and the patients' parameters. So, we perform this study to compare the variations in macular parameters (central thickness, average thickness, macular volume) and peripapillary thickness in different cases of amblyopic eyes versus the normal fellow eyes using spectral-domain optical coherence tomography. In addition, to estimate the relationship of optical coherence tomography variations with different defined patients' parameters (age, sex, best corrected visual acuity, spherical equivalent refractive error, and axial length).
Detailed Description

Amblyopia remains an important cause of low visual acuity,affecting 2% to 6% of the general population. Unilateral amblyopia is defined as reduced best-corrected visual acuity secondary to an abnormal visual experience during the critical period of visual development. Classic causes include strabismus, anisometropia, form deprivation or a combination of these factors .

The normal postnatal reduction (apoptosis) of retinal ganglion cells is arrested in amblyopia which would cause increase in retinal nerve fiber layer thickness as hypothesized by Yen et al .This also would affect the normal maturation of the macula, including movement of Henle's fibers away from the foveola. This would result in increased foveal thickness. Furthermore, because of the reduced apoptosis of retinal ganglion cells, the thickness of the ganglion cell layer in the macula would also be increased.

Optical coherence tomography : is a non-contact and non-invasive technique that help in assessment of retina abnormalities. The high resolving power (10um - Time Domain, 5um - Spectral Domain) provides excellent detail for evaluating the vitreo-retinal interface, neurosensory retinal morphology, and the retinal pigmented epithelial-choroid complex. It generates cross sectional images by analyzing the time delay and magnitude change of low coherence light as it is backscattered by ocular tissues. An infrared scanning beam is split into a sample arm (directed toward the subject) and a reference arm (directed toward a mirror). As the sample beam returns to the instrument it is correlated with the reference arm in order to determine distance and signal change via photodetector measurement. The resulting change in signal amplitude allows tissue differentiation by analysis of the reflective properties, which are matched to a false color scale. As the scanning beam moves across tissue, the sequential longitudinal signals, or A-scans, can be reassembled into a transverse scan yielding cross-sectional images, or B-scans, of the subject. The scans can then be analyzed in a variety of ways providing both empirical measurements (e.g. retinal thickness/volume) and qualitative morphological information.

Study Type Observational
Study Design Observational Model: Case-Crossover
Time Perspective: Cross-Sectional
Target Follow-Up Duration Not Provided
Biospecimen Not Provided
Sampling Method Non-Probability Sample
Study Population

all cooperative patients that fulfill inclusion criteria

  1. Age>16 and <40 years
  2. Patients with unilateral amblyopia ( anisometropic , strabismic and deprivational amblyopia )
Condition Amblyopia
Intervention Device: optical coherence tomography
It generates cross sectional images by analyzing the time delay and magnitude change of low coherence light as it is backscattered by ocular tissues. An infrared scanning beam is split into a sample arm and a reference arm. As the sample beam returns to the instrument it is correlated with the reference arm in order to determine distance and signal change via photodetector measurement. The resulting change in signal amplitude allows tissue differentiation by analysis of the reflective properties, which are matched to a false color scale. As the scanning beam moves across tissue, the sequential longitudinal signals, or A-scans, can be reassembled into a transverse scan yielding cross-sectional images, or B-scans, of the subject. The scans can then be analyzed in a variety of ways providing both empirical measurements (e.g. RNFL or retinal thickness/volume) and qualitative morphological information.
Study Groups/Cohorts
  • anisometropic amblyopia
    Intervention: Device: optical coherence tomography
  • strabismic amblyopia
    Intervention: Device: optical coherence tomography
  • deprivational amblyopia
    Intervention: Device: optical coherence tomography
Publications *

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status Not yet recruiting
Estimated Enrollment
 (submitted: September 13, 2019)
28
Original Estimated Enrollment Same as current
Estimated Study Completion Date October 1, 2022
Estimated Primary Completion Date October 1, 2021   (Final data collection date for primary outcome measure)
Eligibility Criteria

Inclusion Criteria:

  1. Age>16 and <40 years
  2. Patients with unilateral amblyopia ( anisometropic , strabismic and deprivational amblyopia ) .

Exclusion Criteria:

  1. Age<16 and >40 years.
  2. Patients with structural abnormality in their eye , mentally retarded patients .
Sex/Gender
Sexes Eligible for Study: All
Ages 16 Years to 40 Years   (Child, Adult)
Accepts Healthy Volunteers No
Contacts
Contact: alyaa mohamed, post gradate +2001092246445 alyaelkabsh686@gmail.com
Contact: mohamed anwar, lecturer +2001006579873 mohamedanwar70@gmail.com
Listed Location Countries Not Provided
Removed Location Countries  
 
Administrative Information
NCT Number NCT04092361
Other Study ID Numbers OCT changes in amblyopia
Has Data Monitoring Committee Not Provided
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
Plan to Share IPD: Undecided
Responsible Party Alyaa mohamed yousef ahmed elkabsh, Assiut University
Study Sponsor Assiut University
Collaborators Not Provided
Investigators Not Provided
PRS Account Assiut University
Verification Date January 2021