Lipid Thickness Clinical Trial
Official title:
Investigating Abnormal Lipid Layer Thickness and Other Objective Dry Eye Parameters in Patients Seeking Blepharoplasty, and How They Change After Blepharoplasty
Deficiency in tear film lipid layer thickness (LLT) has been implicated in the development of dry eye symptoms, and is influenced to a significant degree by the anatomy and function of the eyelids. Patients who are considering blepharoplasty, even if it is for cosmetic reasons, may subtle differences in eyelid anatomy that pre-dispose them to having an abnormal tear lipid layer. Moreover, the changes in anatomy and contour of the eyelids following blepharoplasty introduce a whole new group of factors, such as an altered palpebral aperture and altered canthal fixation that can further change the eyelid's ability to maintain a healthy tear lipid layer, for better or for worse. Such changes in tear lipid layer can be detected with the aid of a newly acquired tear interferometer (LipiView, Tearscience Inc.), but has never been done in the context of blepharoplasty management. Due to the strong association between LLT and risk of dry eyes, we hope to investigate if there are significant differences in LLT and other objective dry eye parameters in two situations: 1) patients considering blepharoplasty as compared to other patients not considering such procedures 2) patients before and after undergoing blepharoplasty. The results of these investigations can go towards establishing LLT as an important objective parameter to account for before and after blepharoplasty.
Study Objectives and Purpose
1. By cross-sectional analysis, determine if there are significant differences in average
and SD of LLT in a group of patients who are considering blepharoplasty (cases) as compared
to a group of patients from a general ophthalmology clinic who have no lid disturbances
(controls).
2a. Via a prospective study, determine the average and standard deviation of LLT in a group
of patients undergoing blepharoplasty, and how these change in a one month period after
surgery.
2b. Identify, through the same prospective study, if factors such as age and gender are
associated with the direction and magnitude of changes in LLT.
Study design:
Cross-sectional study and Prospective cohort study
Rationale:
1. A cross-sectional study comparing LLT, TBUT and corneal staining in patients who are
about to undergo blepharoplasty against patients who have no complaints of any lid
disturbances.
2. A prospective study observing changes in LLT, TBUT and corneal staining after
blepharoplasty, and if age and gender was associated with these changes.
Methods:
30 patients who are about to undergo blepharoplasty will be recruited from the oculoplastic
clinic. These patients will form the "case" group of the cross-sectional study, and will be
on follow-up for the prospective study.
Another 30 patients will be recruited from the general ophthalmology (ECS) clinic. These
patients are cleared to have no lid disturbances in terms of function or anatomy, and will
serve as the "control" group of the cross-sectional study.
The following assessments will be performed for each patient who is recruited. For patients
involved in the cross-sectional study, they will be assessed only once. For the patients
involved in the prospective study, they will be assessed during the pre-surgery
consultation, and at the standard post-surgery consultations at 1 week and 1 month after
surgery
Procedures to be done
1. LLT measurement with LipiView tear interferometer
2. Fluorescein Dye Tear Break-up Time (TBUT)
3. Fluorescein Dye Corneal Staining
Duration of study: 1 year
;
Allocation: Non-Randomized, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic