Comparison of Evaporimetry With the Established Methods of Tear Film Measurement

• Comparison of tear evaporation to symptoms score [ Time Frame: 15 minutes (10 minutes tear evaporation, 5 minutes symptoms score recording) ] [ Designated as safety issue: No ]
  Tear evaporation measurement compared to dry eye symptoms score (0-15 points).
• Comparison of tear evaporation to Tear Film Break-up Time (TBUT) [ Time Frame: 15 minutes (10 minutes evaporation measurement, 5 minutes TBUT measurement) ] [ Designated as safety issue: No ]
  Comparison of tear evaporation to Tear Film Break-up Time (seconds).
• Comparison of tear evaporation to Schirmer test [ Time Frame: 15 minutes (10 minutes tear evaporation measurement, 5 minutes Schirmer test) ] [ Designated as safety issue: No ]
  Comparison of tear evaporation to Schirmer test (mm)
• Comparison of tear evaporation to corneal staining [ Time Frame: 12 minutes (10 minutes tear evaporation measurements, 2 minutes corneal staining assessment) ] [ Designated as safety issue: No ]

  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

• Comparison of tear evaporation to conjunctival hyperemia [ Time Frame: 11 minutes (10 minutes evaporation measurement, 1 minute conjunctival hyperemia assessment) ] [ Designated as safety issue: No ]

  Comparison of tear evaporation to conjunctival hyperemia (score 1-3):

  1: minimal; 2: moderate; 3: severe

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.

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

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

• Patients without dry eye symptoms
  Patients without dry eye symptoms as measured by standard questionnaire.
  Intervention: Other: Only measurements done on subjects in both groups.
• Patients with dry eye symptoms
  Patients with dry eye symptoms as measured by standard questionnaire.
  Intervention: Other: Only measurements done on subjects in both groups.

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.