Comparison of Evaporimetry With the Established Methods of Tear Film Measurement

Purpose:

To establish whether there is a correlation between dry eye symptoms, age and gender, a difference in symptom intensity in different times of the day, which test (Schirmer or TBUT) better correlates with dry eye symptoms, whether it is possible to reliably use cheap, easy to use hygrometer in everyday clinical setting, and finally whether there is statistically significant correlation between applied tests (TBUT, Schirmer and evaporimetry).

Methods:

Subjects: 45 in group without dry eye related symptoms, and 45 in group with symptoms.

Examination included structured case history (questionnaire), slit lamp examination with fluorescein staining, periocular evaporimetry, TBUT test and Schirmer test.

Study Overview

• Status: Completed
• Conditions: Dry Eye Syndromes
• Intervention / Treatment: Other: Only measurements done on subjects in both groups.

Detailed Description

Purpose:

The purpose of this study was to establish whether there is a correlation between dry eye symptoms, age and gender, any difference in symptom intensity in different times of the day, which test (Schirmer or TBUT) better correlates with dry eye symptoms, whether it is possible to reliably use cheap, easy to use hygrometer in everyday clinical setting, and, finally, whether there is statistically significant correlation between applied tests (TBUT, Schirmer and evaporimetry).

Methods:

Subjects were divided in two groups: 45 in group without dry eye related symptoms, and 45 in group with symptoms.

Examination was performed in the following sequence:

1. structured case history (questionnaire),
2. evaporimetry
3. slit lamp examination with fluorescein staining,
4. TBUT test and
5. Schirmer test I (without anesthetic, closed eyes)

Case history consisted of the following questions:irritation more pronounced on wind? irritation during reading and/or watching TV or computer? irritation more pronounced during winter? gritty sensation in the eyes? irritation more pronounced in the morning or evening? All answers, except to the last question, were graded from 0 (no complaints) to 3 (severe).

Evaporimetry was performed using commercially available hygrometer from HYGROTEC (Titisee-Neustadt, Germany), installed in swimming goggles with its front part sawn off.

First measurement was performed by measuring for 5 minutes with eyes closed. Second measurement also lasted 5 minutes, with eyes kept open, normal blinking, and with subject fixating at one point in distance, with no eye movements.

Measured parameters included:

basal φ (%): relative environment humidity before measurement basal T: environment temperature before measurement closed eye φ (%): relative humidity in front of closed eye open eye φ (%): relative humidity in front of open eye C/O: ratio of φ (%) closed/open eye

• Study Type: Observational
• Enrollment (Actual): 90

Contacts and Locations

Study Locations

• Croatia
  • Zagreb, Croatia, HR-10000
    • Zagreb University Hospital Eye Department

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 61 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients were volunteers who came for a standard ophthalmological exam in Zagreb University Hospital Eye Clinic, and whose enrollment was based on convenience sampling.

Description

Inclusion Criteria:

• patients with or without dry eye symptoms

Exclusion Criteria:

• minors
• pregnant women
• patients with acute eye conditions (inflammation, allergy, trauma)
• patients with chronic eye diseases requiring continuous topical treatment (i.e.glaucoma)
• ocular surface scarring
• patients who did not sign informed consent.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Patients without dry eye symptoms; Patients without dry eye symptoms as measured by standard questionnaire.	Other: Only measurements done on subjects in both groups.; As study compared specific diagnostic procedures, no intervention was done or compared.
Patients with dry eye symptoms; Patients with dry eye symptoms as measured by standard questionnaire.	Other: Only measurements done on subjects in both groups.; As study compared specific diagnostic procedures, no intervention was done or compared.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tear evaporation	Five minutes of tear evaporation measurement with eyes closed and five with open, normal blinking.	10 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of tear evaporation to symptoms score	Tear evaporation measurement compared to dry eye symptoms score (0-15 points).	15 minutes (10 minutes tear evaporation, 5 minutes symptoms score recording)
Comparison of tear evaporation to Tear Film Break-up Time (TBUT)	Comparison of tear evaporation to Tear Film Break-up Time (seconds).	15 minutes (10 minutes evaporation measurement, 5 minutes TBUT measurement)
Comparison of tear evaporation to Schirmer test	Comparison of tear evaporation to Schirmer test (mm)	15 minutes (10 minutes tear evaporation measurement, 5 minutes Schirmer test)
Comparison of tear evaporation to corneal staining	Comparison of tear evaporation to corneal staining using fluorescein (score 1-3): 1:5-10 corneal stains at six o'clock; 2: 10-25 corneal stains; 3: more than 26 diffuse corneal stains	12 minutes (10 minutes tear evaporation measurements, 2 minutes corneal staining assessment)
Comparison of tear evaporation to conjunctival hyperemia	Comparison of tear evaporation to conjunctival hyperemia (score 1-3): 1: minimal; 2: moderate; 3: severe	11 minutes (10 minutes evaporation measurement, 1 minute conjunctival hyperemia assessment)

Collaborators and Investigators

• Sponsor: University of Zagreb
• Investigators: Principal Investigator: Igor Petricek, MD, PhD, Zagreb University Hospital Eye Department, Zagreb, Croatia

Study record dates

Study Major Dates

• Study Start: September 1, 2008
• Primary Completion (Actual): February 1, 2009
• Study Completion (Actual): February 1, 2009

Study Registration Dates

• First Submitted: December 3, 2011
• First Submitted That Met QC Criteria: December 16, 2011
• First Posted (Estimate): December 21, 2011

Study Record Updates

• Last Update Posted (Estimate): December 22, 2011
• Last Update Submitted That Met QC Criteria: December 21, 2011
• Last Verified: December 1, 2011

More Information

Terms related to this study

• Keywords: Dry eye Syndromes
• Additional Relevant MeSH Terms: Eye Diseases; Lacrimal Apparatus Diseases; Keratoconjunctivitis; Conjunctivitis; Conjunctival Diseases; Keratitis; Corneal Diseases; Dry Eye Syndromes; Keratoconjunctivitis Sicca
• Other Study ID Numbers: UZagreb Eye 1; Dry Eye 1 (Other Identifier: Zagreb University Hospital Eye Department, Zagreb, Croatia)