The Homburg Keratoconus Center (HKC)

Study Overview
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Brief Summary
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Aim of this study is to conduct longitudinal and cross-sectional analyses about the corneal ectatic disease Keratoconus based on data obtained from Keratoconus patients in the Homburg Keratoconus Center (HKC). The Homburg Keratoconus Center (HKC) was founded in 2010 and, up to now, comprises more than 2.000 Keratoconus patients. Topographic, tomographic and biomechanic characteristics of the disease are being analyzed with the intention to elucidate how the disease begins and develops during lifetime.

Official Title
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The Homburg Keratoconus Center (HKC) - a Keratoconus Observation Study

Conditions
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Keratoconus

Intervention / Treatment
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* Diagnostic Test: Topographic, tomographic and biomechanical analysis.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All Keratoconus patients presenting in the department of ophthalmology, Saarland University Medical Center, Homburg, Saarland, Germany. Exclusion Criteria: Patients without Keratoconus.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with Keratoconus<br>Aim is to include as many Keratoconus patients as possible with the intention to elucidate how the disease begins and develops during lifetime. | Diagnostic Test: Topographic, tomographic and biomechanical analysis.<br>* The study is based upon data obtained during routine medical follow-ups using the Pentacam high resolution (Oculus, Wetzlar, Germany) the Corvis ST (Oculus, Wetzlar, Germany) the Anterior-Segment Optical Coherence Tomograph (AS-OCT) Casia 2 (Tomey, Nagoya, Japan) the Ocular Response Analyzer (Reichert Technologies, New York, USA).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| An overview about development of anterior corneal curvature in Keratoconus disease during lifetime. | The anterior radius of curvature (ARC, 3mm zone) of Keratoconus patients as measured by the Pentacam high resolution (Oculus, Wetzlar, Germany) at different ages (according to: Belin MW and Duncan JK. Keratoconus: The ABCD grading system. Klin Monbl Augenheilkd. 2016; 233(6): 701-707) is put into relation to the age of the Keratoconus patients. | 01/01/2011-01/01/2019 | 
| An overview about development of posterior corneal curvature in Keratoconus disease during lifetime. | The posterior radius of curvature (PRC, 3mm zone) of Keratoconus patients as measured by the Pentacam high resolution (Oculus, Wetzlar, Germany) at different ages (according to: Belin MW and Duncan JK. Keratoconus: The ABCD grading system. Klin Monbl Augenheilkd. 2016; 233(6): 701-707) is put into relation to the age of the Keratoconus patients. | 01/01/2011-01/01/2019 | 
| An overview about development of the thinnest corneal pachymetry in Keratoconus disease during lifetime. | The thinnest corneal pachymetry of Keratoconus patients as measured by the Pentacam high resolution (Oculus, Wetzlar, Germany) at different ages (according to: Belin MW and Duncan JK. Keratoconus: The ABCD grading system. Klin Monbl Augenheilkd. 2016; 233(6): 701-707) is put into relation to the age of the Keratoconus patients. | 01/01/2011-01/01/2019 | 
| An overview about development of the best corrected distance visual acuity in Keratoconus disease during lifetime. | The best corrected distance visual acuity of Keratoconus patients as raised as part of the clinical examination at different ages (according to: Belin MW and Duncan JK. Keratoconus: The ABCD grading system. Klin Monbl Augenheilkd. 2016; 233(6): 701-707) is put into relation to the age of the Keratoconus patients. | 01/01/2011-01/01/2019 | 
| Reproducibility study: Kmax. | Measurements of Kmax measured by different devices (Pentacam high resolution, Oculus, Wetzlar, Germany; Anterior-Segment Optical Coherence Tomograph (AS-OCT) Casia 2, Tomey, Nagoya, Japan) are being compared and set into relation at different Keratoconus stages with the intention to investigate, whether measurement inaccuracies occur at later Keratoconus stages using different devices. | 01/01/2011-01/01/2019 | 
| Reproducibility study: Thinnest corneal pachymetry. | Measurements of the thinnest corneal pachymetry as measured by different devices (Pentacam high resolution, Oculus, Wetzlar, Germany; Anterior-Segment Optical Coherence Tomograph (AS-OCT) Casia 2, Tomey, Nagoya, Japan) are being compared and set into relation at different Keratoconus stages with the intention to investigate, whether measurement inaccuracies occur at later Keratoconus stages using different devices. | 01/01/2011-01/01/2019 | 
| Reproducibility study: Thinnest corneal pachymetry at the apex position. | Measurements of the thinnest corneal pachymetry at the apex position as measured by different devices (Pentacam high resolution, Oculus, Wetzlar, Germany; Anterior-Segment Optical Coherence Tomograph (AS-OCT) Casia 2, Tomey, Nagoya, Japan) are being compared and set into relation at different Keratoconus stages with the intention to investigate, whether measurement inaccuracies occur at later Keratoconus stages using different devices. | 01/01/2011-01/01/2019 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus, Crosslinking, Intracorneal ring segments, Gas-permeable rigid contact-lenses, Penetrating Keratoplasty, Deep anterior lamellar Keratoplasty, ABCD Grading System