Comparison of DCT, ORA and GAT in Eyes After Penetrating Keratoplasty - Full Text View

Sponsored by:	Sheba Medical Center
Information provided by:	Sheba Medical Center
ClinicalTrials.gov Identifier:	NCT00834782

Purpose

To compare intraocular pressure (IOP) measured by the Reichert Ocular Response Analyzer (ORA), Pascal dynamic contour tonometer (DCT) and Goldmann applanation tonometer (GAT) in eyes after Penetrating Keratoplasty (KPL)

Condition	Intervention	Phase
Corneal Transplantation	Procedure: IOP measurement	Phase IV

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Diagnostic, Non-Randomized, Single Blind (Investigator), Single Group Assignment, Efficacy Study
Official Title:	Comparison of Pascal Dynamic Contour Tonometer, Reichart Ocular Response Analyzer and Goldmann Applanation Tonometer in Eyes After Penetrating Keratoplasty

Further study details as provided by Sheba Medical Center:

Primary Outcome Measures:

Intra ocular pressure [ Time Frame: 1 year ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Corneal compensated intra ocular pressure, Corneal hysteresis, Corneal resistance factor [ Time Frame: 1 year ] [ Designated as safety issue: No ]

Estimated Enrollment:	30
Study Start Date:	March 2009
Estimated Study Completion Date:	March 2010
Estimated Primary Completion Date:	March 2010 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
IOP: Experimental Measuring IOP	Procedure: IOP measurement Measuring IOP

Detailed Description:

A few tonometers are used today in clinical practice for measuring intra ocular pressure (IOP). Each tonometer is based on different technology.

Post penetrating keratoplasty (PK) eyes are at risk for developing secondary glaucoma (9-14%). Elevation of the IOP may cause rejection of the graft or alternately a loss in the endothelial cell layer count causing decompensation of the cornea. Therefore, measuring accurately the IOP in this population is of great importance.

Measuring IOP in post PK is not an easy challenge, mainly because of parameters like the central corneal thickness (CCT), the curvature of the cornea, the axial length and biomechanical properties which diverse from normal eyes.

The Goldmann applanation tonometer (GAT) is the gold standard tonometer for measuring IOP and is the most popular tonometer clinically used. IOP measurements via the GAT are based on the assumption that the CCT is constant. post PK eyes CCT might diverse from normal eyes causing GAT IOP measurements to be inaccurate. The Pascal dynamic contour tonometer (DCT) measures IOP independently of corneal parameters. The Ocular response analyzer (ORA) is based on a non contact technique of measurement. The tonometer is thought to be independent of factors such as CCT.

The aim of the study is to compare intraocular pressure (IOP) measured by the Reichert Ocular Response Analyzer (ORA), Pascal dynamic contour tonometer (DCT) and Goldmann applanation tonometer (GAT) in eyes after Penetrating Keratoplasty (KPL). In addition its aim is to discover the dependence of different parameters, like - CCT, curvature of the cornea, axial length and biomechanical properties on IOP measurement to elucidate the appropriate tonometer for this population.

Eligibility

Ages Eligible for Study:	18 Years to 90 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Eyes after KPL surgery at the Goldschleger Eye Institute in the last 10 years.

Exclusion Criteria:

Uncooperative subjects for whom good quality results are unattainable.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00834782

Contacts

Contact: Ido D Fabian, Dr

+9727830444

didifabian@gmail.com

Locations

Israel
Goldschleger eye institute, Sheba medical center
Ramat Gan, Israel

Sponsors and Collaborators

Sheba Medical Center

Investigators

Study Chair:

Shlomo Melamed, Prof

Sheba medical center, head of Sam rotberg glaucoma center

More Information

Publications:

Congdon NG, Broman AT, Bandeen-Roche K, Grover D, Quigley HA. Central corneal thickness and corneal hysteresis associated with glaucoma damage. Am J Ophthalmol. 2006 May;141(5):868-75. Epub 2006 Mar 9.

Jain AK, Saini JS, Gupta R. Tonometry in normal and scarred corneas, and in postkeratoplasty eyes: a comparative study of the Goldmann, the ProTon and the Schiotz tonometers. Indian J Ophthalmol. 2000 Mar;48(1):25-32.

Kerautret J, Colin J, Touboul D, Roberts C. Biomechanical characteristics of the ectatic cornea. J Cataract Refract Surg. 2008 Mar;34(3):510-3.

Luce DA. Determining in vivo biomechanical properties of the cornea with an ocular response analyzer. J Cataract Refract Surg. 2005 Jan;31(1):156-62.

Medeiros FA, Weinreb RN. Evaluation of the influence of corneal biomechanical properties on intraocular pressure measurements using the ocular response analyzer. J Glaucoma. 2006 Oct;15(5):364-70.

Mollan SP, Wolffsohn JS, Nessim M, Laiquzzaman M, Sivakumar S, Hartley S, Shah S. Accuracy of Goldmann, ocular response analyser, Pascal and TonoPen XL tonometry in keratoconic and normal eyes. Br J Ophthalmol. 2008 Dec;92(12):1661-5. Epub 2008 Aug 29.

Pandav SS, Sharma A, Gupta A, Sharma SK, Gupta A, Patnaik B. Reliability of proton and goldmann applanation tonometers in normal and postkeratoplasty eyes. Ophthalmology. 2002 May;109(5):979-84.

Rao VJ, Gnanaraj L, Mitchell KW, Figueiredo FC. Clinical comparison of ocular blood flow tonometer, Tonopen, and Goldmann applanation tonometer for measuring intraocular pressure in postkeratoplasty eyes. Cornea. 2001 Nov;20(8):834-8.

Touboul D, Roberts C, Kérautret J, Garra C, Maurice-Tison S, Saubusse E, Colin J. Correlations between corneal hysteresis, intraocular pressure, and corneal central pachymetry. J Cataract Refract Surg. 2008 Apr;34(4):616-22.

Responsible Party:	Sheba Medical Center, Goldschleger eye institute ( Dr Ido Didi Fabian )
Study ID Numbers:	SHEBA-09-6902-IDF-CTIL
Study First Received:	February 2, 2009
Last Updated:	February 4, 2009
ClinicalTrials.gov Identifier:	NCT00834782
Health Authority:	Israel: Israeli Health Ministry Pharmaceutical Administration

Keywords provided by Sheba Medical Center:

PK
IOP

ClinicalTrials.gov processed this record on February 12, 2009