Comparison of Three Different No-contact Pachymetries

Study Overview
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Brief Summary
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Study wants to compare central corneal thickness (CCT) obtained through 3 different no-contact instruments and to compare them with contact ultrasound pachymetry, actually the gold standard technique.

Detailed Description
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Corneal pachymetry is the measurement of corneal thickness, usually expressed in microns (μ). Pachymetry is systematically used for the monitoring of corneal oedema, for the management and assessment of the progression risk of the ocular hypertension, for the diagnosis, the management and follow-up of keratoconus, as well as it is important in the pre and postoperative management of corneal surgical procedures. CCT is a factor well known to influence tonometry. Its assessment is fundamental in glaucoma practice to allow a correct intraocular pressure (IOP) evaluation. The purpose of this study is to compare CCT measurements using four different instruments: Scheimpflug camera tomography, spectral-domain optical coherence tomography (SD-OCT), anterior chamber SD-OCT and ultrasound pachymetry.

Official Title
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Phase 4 Study of Comparison Among 3 Different No-contact Instruments to Valuate Central Corneal Thickness

Conditions
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Corneal Thickness

Intervention / Treatment
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* Device: Pachymetry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: subjects that gave a valid consensus to be included in this experimentation, aged between 18 and 75 years, Best-Corrected Visual Acuity (BCVA) of 20/100 or better, refraction included between -6 and +6 dioptres, astigmatism included between -2 and +2 dioptres. Exclusion Criteria: History of refractive surgery or any keratoplasty procedure, corneal opacities or diseases that make not suitable applanation tonometry or pachymetry. Use of contact lenses. History of corneal dystrophies or degenerative diseases, (like keratoconus and pellucid marginal degeneration). History of glaucoma or ocular hypertension.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pachymetry<br>All recruited volunteers in present study, that underwent pachymetry measurement with four different instruments | Device: Pachymetry<br>* Healthy volunteers recruited among subject that underwent a routine ophthalmologic evaluation or among both students and workers at our clinic, will be submitted to CCT measurement through four different instruments: Scheimpflug camera tomography, SD-OCT, anterior chamber SD-OCT, and finally with US pachymeter.<br>* Other names: Ultrasound pachymeter (Pacline© - Optikon ind., Rome, Italy).;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central Corneal Thickness (CCT) expressed in microns (μm) | to valuate differences among all obtained no-contact CCT measurements and compare them with the CCT measured with the reference tool (Ultrasound pachymeter). | partecipants will be followed for one day, i. e. until the CCT measurements with all instruments object of present study are taken | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central Corneal Thickness (CCT) expressed in microns (μm) | to valuate test-retest reliability of each instrument | partecipants will be followed for one day, i. e. until the CCT measurements with all instruments object of present study are taken | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Central Corneal Thickness, Pachymetry