An observational study in Recurrent Pterygium and Conjunctival Scarring, sponsored by Instituto de Oftalmología Fundación Conde de Valenciana. Completed at 1 site in Mexico. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-09.
Sponsored by Instituto de Oftalmología Fundación Conde de Valenciana · Observational
This observational study aims to evaluate and validate a digital colorimetric scale for the objective assessment of conjunctival scarring in patients with recurrent pterygium. Pterygium is a fibrovascular growth of the conjunctiva that may recur after surgical removal, and the evaluation of postoperative scarring is often subjective during clinical examination.
Digital photographs of the anterior segment of the eye will be obtained using slit-lamp imaging. These images will be analyzed using image processing software (Fiji/ImageJ) to quantify colorimetric and vascular parameters of the conjunctival scar tissue. Measurements such as hyperemia and vascular density will be obtained through digital image analysis algorithms.
The study will assess whether the proposed digital colorimetric scale provides an objective and reproducible method for evaluating conjunctival scarring associated with recurrent pterygium. Interobserver agreement and statistical analyses will be performed to determine the reliability of the measurements.
The results of this study may contribute to improving the objective evaluation of postoperative conjunctival changes and may help standardize the clinical assessment of pterygium recurrence.
Pterygium is a common ocular surface disorder characterized by a fibrovascular proliferation of conjunctival tissue extending onto the cornea. Despite surgical treatment, recurrence remains a frequent complication, and postoperative conjunctival scarring is often associated with disease recurrence and ocular surface inflammation. Currently, the clinical evaluation of conjunctival scarring and hyperemia is largely subjective and depends on slit-lamp examination, which may lead to variability between observers.
The objective evaluation of conjunctival vascularization and scar-related changes could improve the standardization of postoperative assessments and allow better monitoring of disease progression or recurrence. Digital image analysis has emerged as a useful tool for quantifying ocular surface features such as vascular density, redness, and tissue morphology.
The purpose of this observational study is to evaluate and validate a digital colorimetric scale designed to objectively quantify conjunctival scarring associated with recurrent pterygium. The study will analyze anterior segment photographs obtained during routine ophthalmologic examinations.
Digital slit-lamp photographs will be collected from patients diagnosed with recurrent pterygium. Images will be analyzed using the open-source software Fiji/ImageJ, which allows quantitative analysis of colorimetric and vascular parameters. Image processing algorithms will be applied to extract objective measurements related to conjunctival redness and vascular density within the scarred conjunctival tissue.
Measurements will be obtained from standardized regions of interest within the conjunctiva. Quantitative parameters will include colorimetric intensity values, vascular pixel density, and other digital markers of conjunctival hyperemia. These measurements will be compared with clinical assessments performed by ophthalmologists in order to evaluate the reliability and reproducibility of the proposed colorimetric scale.
Statistical analyses will be performed to determine the correlation between the digital measurements and clinical grading systems. Interobserver agreement and measurement reproducibility will also be evaluated.
The findings of this study may contribute to the development of standardized digital tools for the objective assessment of conjunctival scarring in patients with recurrent pterygium. Such tools may improve clinical monitoring and facilitate future research on ocular surface diseases and postoperative outcomes.
109 studies on the registry are indexed under Pterygium; 9 are open to participants now.
This study's enrollment of 25 is below the median of 58 across 14 observational studies indexed under Pterygium.
Browse Pterygium studies →Instituto de Oftalmología Fundación Conde de Valenciana is the lead sponsor of 45 studies on the registry; 10 are open to participants now.
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Adult patients diagnosed with primary or recurrent pterygium evaluated at an ophthalmology clinic. Slit-lamp photographs of the anterior segment are obtained during routine clinical evaluation and analyzed using digital image analysis to quantify conjunctival vascularization and colorimetric characteristics.
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You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants diagnosed with recurrent pterygium. Slit-lamp photographs of the anterior segment are obtained and analyzed using digital colorimetric image analysis to quantify conjunctival vascularization and scarring.
Participants diagnosed with primary pterygium used as a comparison group. Slit-lamp images are analyzed using the same digital colorimetric image analysis to evaluate conjunctival vascularization and tissue characteristics.
Quantitative Assessment of Conjunctival Vascularization Using Digital Colorimetric Image Analysis
Conjunctival vascularization associated with pterygium will be quantified using digital image analysis of slit-lamp photographs. Images will be processed with Fiji/ImageJ software to measure vascular pixel density and colorimetric intensity values within a defined conjunctival region of interest.
Time frame: Baseline (at time of clinical image acquisition)
Correlation Between Digital Vascular Density and Clinical Hyperemia Grading
Correlation between vascular density quantified through digital image analysis and clinical grading of conjunctival hyperemia performed during slit-lamp examination.
Time frame: Baseline
Plan to share: No — Individual participant data (IPD) will not be shared due to patient confidentiality and institutional data protection policies. Only aggregated results will be reported in scientific publications.
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This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Instituto de Oftalmología Fundación Conde de Valenciana