Screening Aid to Identify Corneas That May Have Pathologies or Other Conditions

Corneal Diseases Clinical Trial

Official title:

Corneal Analysis - Pathology Detection Aid

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00396188
• Other study ID #: Atlas II-2006-1-v1
• Status: Completed
• Phase: Phase 1
• First received: November 2, 2006
• Last updated: August 13, 2015
• Start date: February 2007
• Est. completion date: February 2008

Study information

• Verified date: August 2015
• Source: Carl Zeiss Meditec, Inc.
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

The purpose of this study is to determine the ability of a proprietary software screening tool to discriminate normal corneas (front surface of the eye) from previously diagnosed corneal conditions (diseases/surgeries/pathologies) and to determine the repeatabiltity and reproducibility of the Atlas II corneal topographer in normal human corneas.

Description:

1. To establish reference values for SF, CIM, and TKM in subjects with normal corneas.

2. To establish reference values for SF, CIM, and TKM in subjects who underwent myopic laser vision correction.

3. To establish reference values for SF, CIM, and TKM in subjects who underwent hyperopic laser vision correction.

4. To establish reference values for SF, CIM, and TKM in subjects who were diagnosed to have keratoconus.

5. To establish reference values for SF, CIM, and TKM in subjects with history of orthokeratology.

6. To establish reference values for SF, CIM, and TKM in subjects with previously diagnosed corneal conditions (diseases/pathologies/surgeries) affecting the corneal surface that are not listed above.

7. To determine the repeatabiltity and reproducibility of the Atlas II corneal topographer in normal human corneas using true elevation data and axial curvature.

8. To determine the sensitivity, specificity, and accuracy of the Pathfinder II Corneal Analysis software in discriminating normal corneas from previously diagnosed corneal conditions (diseases/pathologies/surgeries) affecting the corneal surface (Phase II).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 769
• Est. completion date: February 2008
• Est. primary completion date: February 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

Normals

• Patients seeking initial laser vision correction that were screened to be good candidates for the procedure.

• No history of refractive or other ocular surgery.

• No corneal pathologies.

• Normal corneal topography.

• Contact lens wearers should discontinue use at least 2 weeks for hard contacts, and 3 days for soft lenses prior to imaging.

Keratoconus

• An irregular cornea determined by distorted keratometry mires, distortion of the retinoscopic, or ophthalmoscopic red reflex (or a combination of these)

• At least one of the following biomicroscopic signs: Vogt's striae, Fleischer's ring of >2 mm arc, or corneal scarring consistent with keratoconus.

• Contact lens wearers should discontinue use preferably 1 day or at least half an hour prior to imaging.

Myopic Laser Vision Correction

Patients who have undergone myopic:

• LASIK

• PRK

• LASEK

Hyperopic Laser Vision Correction

Patients who have undergone hyperopic:

• LASIK

• PRK

• LASEK

Orthokeratology

• Patients using specially designed rigid contact lenses to reshape the cornea to temporarily reduce or eliminate refractive error.

• Subjects must be 18 years of age or older; able and willing to make the required visit; and able and willing to give consent.

Exclusion Criteria:

• Patients that underwent corneal transplantation or any ocular surgery for the following categories: normal, keratoconus, and orthokeratology)

• Any active infection or inflammation of the cornea.

• PI decides that subject is not suitable due to medical risk.

Study Design

Observational Model: Case Control, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Corneal Diseases

Locations

Country	Name	City	State
United States	Pacific University	Forest Grove	Oregon
United States	Dishler Laser Institute	Greenwood Village	Colorado
United States	Shiley Eye Center-University of California San Diego	La Jolla	California
United States	Carmel Mountain Vision Care Center	San Diego	California

Sponsors (1)

Lead Sponsor	Collaborator
Carl Zeiss Meditec, Inc.

Country where clinical trial is conducted

United States, 

References & Publications (2)

Twa MD, Parthasarathy S, Roberts C, Mahmoud AM, Raasch TW, Bullimore MA. Automated decision tree classification of corneal shape. Optom Vis Sci. 2005 Dec;82(12):1038-46. — View Citation

Zadnik K, Barr JT, Edrington TB, Everett DF, Jameson M, McMahon TT, Shin JA, Sterling JL, Wagner H, Gordon MO. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. Invest Ophthalmol Vis Sci. 1998 Dec;39(13):2537-46. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Reference values of normal and previously diagnosed corneal conditions by Atlas II corneal topographer		1-2 hours	No
Secondary	Repeatabiltity and reproducibility of the Atlas II corneal topographer in human corneas		1-2 hours	No