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Effect of Contact Lens With Alginic Acid in Dry Eye Patients

This study has been completed.
Singapore Eye Research Institute
SEED Company Pte Ltd
Information provided by (Responsible Party):
Louis Tong, Singapore National Eye Centre Identifier:
First received: August 6, 2013
Last updated: May 18, 2015
Last verified: June 2014
Contact lens induced dry eyes leads to lens intolerance and discontinuation. Incidence of dry eye in contact lens wearer is significantly higher in Asian population compared to other ethnic group considering Asian has lower tear break up time. Disruptions of tear integrity in contact lens wearer will further exacerbate the condition. Factors for successful contact lens fitting derive from the biocompatibility of lens material, lens design and stability of tear film in front of the contact lens. This study aim to investigate the efficacy of a novel daily disposable contact lens with zwitterionic material that contains alginic acid which act as a moisturizing agent. The improved lens material may likely improve the comfort and treat symptomatic wearers.

Condition Intervention
Dry Eyes Device: Contact Lens with alginic acid Device: Contact Lens without alginic acid

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Official Title: To Evaluate Effect of Contact Lens With Alginic Acid (7 Days) in Patients With Dry Eye

Resource links provided by NLM:

Further study details as provided by Louis Tong, Singapore National Eye Centre:

Primary Outcome Measures:
  • • Difference of Visual Analogue Scale (VAS) for the ocular discomfort between control and treatment group. [ Time Frame: 7 days ]

    A VAS will be applied to evaluate dry eye symptoms as described by Schaumberg et al. (Schaumberg, Gulati et al. 2007). The scores will be recorded separately for frequency and severity of dry eye symptoms. The patient will be asked to check a point on a 100-mm line that corresponds to the degree of the symptom. The location of the mark made by the patient for each question will be measured in mm from the left hand side of the 100 mm line and recorded in mm. For the follow up visits, which measured the distance between the mark made by the patient and the central anchor, a negative value will be recorded if left of the anchor and a positive value if right of the anchor.

    A global score will be calculated by multiplying the frequency score by the severity score and taking the square root of the result (to transform back to the original scale).

Secondary Outcome Measures:
  • Tear lipid layer thickness measurements of LipiView [ Time Frame: 7 days ]
    During the measurement of each eye, the participants place their chins on a chin rest and look at a single white light source for 30 seconds. During this period, participants are encouraged to blink freely at a comfortable rate which the assessor measures the LLT.

  • Schirmers I reading [ Time Frame: 7 days ]

    This will be done with the standard strips currently used at SERI (5 mm wide with a notch for folding) (Sno strips, Bausch&Lomb, France) without anaesthetic. The strips will be positioned over the inferior temporal half of the lower lid margin in both eyes at the same time.

    The study participant will be asked to close their eyes during the test. Any excessive irritation signs or reflex tearing will be noted. The extent of the wetting in each strip will be recorded after 5 minutes of testing. The strip will be collected and stored in 1.5ml eppendorf tubes at -80˚C until further tear lipid and protein analysis.

  • Tear break up time (TBUT) [ Time Frame: 7 days ]
    Keratograph 5M will be used to perform the non invasive tear break up time. Patient will sit comfortably in front of the instrument and blink freely while fixing on a target directly ahead. Once the patient is ready, patient will be instructed to blink once and refrain from blinking. Keratograph 5M is fully automated and it will capture any break or distortion in the image and the time of the break will be noted. Three readings will be taken for each eye to get the average value.

  • Corneal flourescein staining [ Time Frame: 7 days ]
    Routine anterior segment assessment with a slit lamp microscope will be carried out to evaluate corneal health and clinical signs. Assessment of positive fluorescein staining on cornea and conjunctiva will be assessed. A scoring system will be applied as adapted by Bron A, Evans VE, Smith JA. (2003).The grading scheme depends on the intensity and the area of the staining for each panel with scale from 0 to 5. Briefly, there will be corneal zone and exposed interpalpebral conjunctival regions as shown in Figure 2. The staining increases by 1 log unit for the first 2 panel and ½ unit log for the subsequent 3 panel.

  • Tear proteomic analysis [ Time Frame: 7 days ]
    The strip will be collected and stored in 1.5ml eppendorf tubes at -80˚C until further tear lipid and protein analysis.

Enrollment: 30
Study Start Date: February 2014
Study Completion Date: December 2014
Primary Completion Date: December 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Contact Lens with alginic acid Device: Contact Lens with alginic acid
Worn for 7 days, at least 8 hours a day
Placebo Comparator: Contact lens without alginic acid Device: Contact Lens without alginic acid
Worn for 7 days, at least 8 hours a day

  Show Detailed Description


Ages Eligible for Study:   21 Years to 90 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. Age of 21 years old and above and has full legal capacity to volunteer
  2. Soft contact lens wearer
  3. Willing to wear study lenses for at least 8 hours/day for 7 days
  4. Reports dryness symptoms with contact lens wear on questionnaire.
  5. Schirmers I with no aneasthesia of less than 10mm
  6. Is willing and able to follow instructions and maintain the appointment schedule
  7. Vision correctable to 6/9 (Snellen) or better in each eye at distance with study lenses at baseline
  8. Has a contact lens prescription between +4.00 to -6.00D with astigmatism <=-1.00

Exclusion Criteria:

  1. Requires concurrent ocular medication
  2. Is participating in any concurrent clinical or research study
  3. Has used Restasis® in the last 3 months
  4. Wears punctal plugs fitted in the last 1 month
  5. Any systemic illness which would contraindicate lens wear
  6. Diabetic
  7. Has had an eye injury or surgery within the last 3 months
  8. Keratoconus or other corneal irregularity
  9. Has had ocular surgery done within the previous 3 months
  10. Active ocular surface conditions such as infection or pterygium that may affect tear film stability.
  11. Is pregnant, lactating or planning a pregnancy
  12. Any other specified reason as determined by clinical investigator.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01918410

Singapore National Eye Centre/ Singapore Eye Research Institute
Singapore, Singapore, 168751
Sponsors and Collaborators
Louis Tong
Singapore Eye Research Institute
SEED Company Pte Ltd
  More Information

Responsible Party: Louis Tong, Clinician-Scientist, Senior Consultant, Singapore National Eye Centre Identifier: NCT01918410     History of Changes
Other Study ID Numbers: SEED2013
Study First Received: August 6, 2013
Last Updated: May 18, 2015

Keywords provided by Louis Tong, Singapore National Eye Centre:
contact lens
dry eyes

Additional relevant MeSH terms:
Keratoconjunctivitis Sicca
Dry Eye Syndromes
Conjunctival Diseases
Eye Diseases
Corneal Diseases
Lacrimal Apparatus Diseases
Alginic acid
Radiation-Protective Agents
Protective Agents
Physiological Effects of Drugs processed this record on September 20, 2017