The lipid layer and stability of the preocular tear film in newborns and infants☆
Received 6 February 2002; accepted 25 February 2003.
Abstract
Purpose
To measure the thickness of the precorneal lipid layer and the stability of the precorneal tear film in neonates and infants in the first 6 postnatal months.
Design
Prospective, observational case series.
Participants
One hundred ninety-eight neonates and infants in the newborn nursery.
Methods
The Keeler Tearscope Plus (Keeler Instruments Inc., Broomall, PA) was used to evaluate lipid layer thickness by interference fringe biomicroscopy and directly to measure noninvasive tear breakup time (NIBUT). The thickness was classified from level 1 (open meshwork—very thin) to level 9 (colored fringe pattern—very thick).
Main outcome measures
Noninvasive tear breakup time in seconds and classification level of lipid layer thickness.
Results
The mean lipid layer classification for all newborns was 8.3 ± 0.9, with no significant difference between genders. The thickest classifications (levels 8 and 9) were found in 83.3% of all infants. At 3 and 6 postnatal months, all infants studied had a lipid layer classification of 9. Mean NIBUT was 32.5 ± 5.2 seconds (range, 17.6–48.5 seconds) and was not significantly different whether stratified by race, postconceptional age, or birthweight. However, although NIBUT was longer in males at birth (35.1 ± 4.2 seconds versus 29.4 ± 4.5 seconds; P < 0.001), it was equal in both genders at 3 and 6 postnatal months.
Conclusions
In the first 6 postnatal months, the lipid layer of the tear film is much thicker than in adults. The NIBUT in newborns is prolonged compared with adult values. This thick lipid layer in infants provides stability that may help prevent the thin aqueous layer from evaporating.
1Department of Ophthalmology, Jules Stein Eye Institute, U.C.L.A. School of Medicine, Los Angeles, California, USA.
2Department of Pediatrics, U.C.L.A. School of Medicine, Los Angeles, California, USA
3Research and Education Institute, Harbor-UCLA Medical Center, Torrance, California, USA
4Centre For Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia, Nedlands, Western Australia, Australia
Correspondence to Sherwin J. Isenberg, MD, Department of Ophthalmology, Harbor-UCLA Medical Center, 1000 West Carson Street, Torrance, CA 90509, USA.
Supported in part by National Center for Research Resources (GCRC grant no.: M01 RR00425, Bethesda, MD); the Sara Kolb Fund, Los Angeles, CA; the Kirchgessner Foundation, Los Angeles, CA; and Research to Prevent Blindness, Inc., New York, New York (Senior Scientific Investigator Award to SJI).
Dr. Guillon has a financial interest in the Tearscope Plus.
ABSTRACT