- 作者：Samiyyah M. Sledge ; BS ; Hussain Khimji ; Douglas Borchman ; PhD ; borchman@louisville.edu" class="auth_mail" title="E-mail the corresponding author ; Alexandria L. Oliver ; MS ; Heidi Michael ; Emily K. Dennis ; BS ; Dylan Gerlach ; MS ; Rahul Bhola ; MD ; Elsa Stephen ; MD
- 关键词：dry eye ; hydroxyl lipids ; meibum ; tear evaporation ; tear film lipid layer
- 刊名：The Ocular Surface
- 出版年：2016
- 出版时间：October 2016
- 年：2016
- 卷：14
- 期：4
- 页码：447-459
- 全文大小：1987 K
Methods
Revap were determined gravimetrically. Hydrocarbon chain conformation and structure were measured using a Raman microscope. Six 1-hydroxyl hydrocarbons (11-24 carbons in length) and human meibum were studied. Reflex tears were obtained from a 62-year-old male.
Results
The Raman scattering intensity of the lipid film deviated by about 7 % for hydroxyl lipids and varied by 21 % for meibum films across the entire film at a resolution of 5 μm2. All of the surface lipids were ordered. Revap of the shorter chain hydroxyl lipids were slightly (7%) but significantly lower compared with the longer chain hydroxyl lipids. Revap of both groups was essentially similar to that of buffer. A hydroxyl lipid film did not influence Revap over an estimated average thickness range of 0.69 to >6.9 μm. Revap of human tears and buffer with and without human meibum (34.4 μm thick) was not significantly different. Revap of human tears was not significantly different from buffer.
Conclusions
Human meibum and hydroxyl lipids, regardless of their fluidity, chain length, or thickness did not inhibit Revap of buffer or tears even though they completely covered the surface. It is unlikely that hydroxyl lipids can be used to inhibit Revap of reservoirs. Our data do not support the widely accepted (yet unconfirmed) idea that the tear film lipid layer inhibits Revap of tears.