Reliability of Dynamic Contour Tonometry (DCT)

Sponsor

University of Catanzaro (Other)

Overall Status

Completed

CT.gov ID

NCT01579331

Collaborator

(none)

102

Enrollment

Location

Arm

14.1

Duration (Months)

7.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Study wants to test reliability Dynamic Contour Tonometry (DCT) in measuring intraocular pressure (IOP) and Ocular Pulse Amplitude (OPA). IOP values obtained with DCT will then be compared with IOP values obtained with Goldmann Applanation Tonometry (GAT), actually the gold standard technique.

Condition or Disease	Intervention/Treatment	Phase
Intraocular Pressure Central Corneal Thickness	Device: DCT (PASCAL© Tonometer) IOP and OPA measurement	Phase 4

Detailed Description

Healthy volunteers recruited among subjects who underwent a routine ophthalmologic evaluation or among students and workers both at our clinic, will undergo a series of 5 DCT to evaluate eventual differences among the measurements.

A diurnal IOP curve performed though GAT, composed of 3 measurements (9am, noon, 4pm) will be taken 1 to 7 days before the DCT.

At the end of the DCT measurements a last GAT will be taken to control eventual IOP changes versus previous GAT values obtained through the diurnal curve.

After 3 weeks observers will contact patients to record eventual adverse events. If examiners consider it as necessary, a safety ophthalmological evaluation will then be performed.

Study Design

Study Type:

Interventional

Actual Enrollment :

102 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Primary Purpose:

Diagnostic

Official Title:

Study of Test-retest Reliability of Dynamic Contour Tonometry and Its Correlation With Goldmann Applanation Tonometry

Study Start Date :

Jul 1, 2011

Actual Primary Completion Date :

Aug 1, 2012

Actual Study Completion Date :

Sep 1, 2012

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Dynamic Contour Tonometry All recruited volunteers in present study, that underwent diurnal GAT tonometry (3 measures) and 5 DCT measurements.	Device: DCT (PASCAL© Tonometer) IOP and OPA measurement Healthy volunteers recruited among subject that underwent a routine ophthalmologic evaluation or among both students and workers at our clinic, will undergo a series of 5 Dynamic contour tonometries to evaluate eventual differences among measurements. Patients will be controlled for 30 days. A diurnal IOP curve performed though GAT, composed of 3 measurements (9am, noon, 4pm) will be taken 1 to 7 days before the DCT. At the end of the DCT measurements a last GAT will be taken to control eventual IOP changes versus previous GAT values obtained through the diurnal curve. Other Names: Goldmann Applanation Tonometry (AT900© - Haag-Streit AG, Koeniz, Switzerland) Dynamic Contour Tonometry (PASCAL© Tonometer - Ziemer Ophthalmic Systems AG, Port, Switzerland) Ultrasound pachymeter (Pacline© - Optikon ind., Rome, Italy).

Arm

Intervention/Treatment

Experimental: Dynamic Contour Tonometry

All recruited volunteers in present study, that underwent diurnal GAT tonometry (3 measures) and 5 DCT measurements.

Device: DCT (PASCAL© Tonometer) IOP and OPA measurement

Healthy volunteers recruited among subject that underwent a routine ophthalmologic evaluation or among both students and workers at our clinic, will undergo a series of 5 Dynamic contour tonometries to evaluate eventual differences among measurements. Patients will be controlled for 30 days. A diurnal IOP curve performed though GAT, composed of 3 measurements (9am, noon, 4pm) will be taken 1 to 7 days before the DCT. At the end of the DCT measurements a last GAT will be taken to control eventual IOP changes versus previous GAT values obtained through the diurnal curve.

Other Names:

Goldmann Applanation Tonometry (AT900© - Haag-Streit AG, Koeniz, Switzerland)

Dynamic Contour Tonometry (PASCAL© Tonometer - Ziemer Ophthalmic Systems AG, Port, Switzerland)

Ultrasound pachymeter (Pacline© - Optikon ind., Rome, Italy).

Outcome Measures

Primary Outcome Measures

IOP expressed in mmHg [measurements will be taken in a single day, in approximately 30 minutes.]
5 consecutive valid DCT measurements will be taken. After test-retest reliability of these DCT measurements will then be calculated (difference expressed in mmHg between 1st and 5th DCT measurements of IOP. Coefficient of Variation will also be calculated).
OPA expressed in mmHg [measurements will be taken in a single day, in approximately 30 minutes.]
5 consecutive valid DCT measurements will be taken. After test-retest reliability of these DCT measurements will then be calculated (difference expressed in mmHg between 1st and 5th DCT measurements of OPA. Coefficient of Variation will also be calculated).

Secondary Outcome Measures

IOP difference (expressed in mmHG) between first GAT and DCT [partecipants will undergo a GAT diurnal tonometric curve (one day duration) and after one to seven days will undergo 5 DCT (approx. duration 30 minutes)]
The diurnal tonometric curve (i.e. IOP at 9am, noon, 4pm) will be measured using GAT. After 1 to 7 days, 5 different IOP measurements recorded every 2 minutes (+/- 1) will be measured at 9am (+/- 15 minutes) using DCT. The difference between GAT and DCT values will be calculated.
IOP difference (expressed in mmHG) between DCT and last GAT [partecipants will undergo 5 DCT and after these, to a single GAT measurement(approx. duration 30 minutes)]
5 different IOP measurements recorded every 2 minutes (+/- 1) will be measured at 9am (+/- 15 minutes) using DCT. After 1-2 minutes a single GAT measurement will be recorded. The difference between GAT and DCT values will be calculated.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

healthy subjects giving a valid consent to be included in this experimentation
age between 18 and 80 years
best corrected visual acuity (BCVA) of at least 20/100
refraction ranging from -6 to +6 dioptres, with an astigmatism ranging from -2 to +2 dioptres