This article is more than 5 years old. Information may no longer be current.
Postmenopausal women require special care in LASIK
Study shows that postmenopausal women with dry eye have thinner corneas than postmenopausal women with no dry eye.
Click Here to Manage Email Alerts
Corneal thickness values are significantly lower in women with dry eye than in women without dry eye, according to a study in Cornea. This difference should be taken into account in evaluating candidates for LASIK and other refractive procedures involving photoablation, the study authors said.
“Special care must be taken with these reduced corneal thickness values when selecting postmenopausal women for surgery involving corneal photoablation,” said Juan Alberto Sanchis-Gimeno, MD, PhD, and colleagues in the department of anatomy and human embryology at the University of Valencia, Spain.
Studies suggest that more than 3.2 million women over the age of 50 years suffer from dry eye syndrome in the United States alone, the study authors said. They also noted that an increasing prevalence of dry eye syndrome may be expected with the aging of the population in the developed world.
“Despite the great prevalence of dry eye in women aged 50 and over and the possible influence of dry eye in reduced corneal thickness values, we have not found any specific studies addressing corneal thickness values of postmenopausal women with dry eye,” Dr. Sanchis-Gimeno and colleagues wrote.
The purpose of their study was to compare the corneal thickness values in postmenopausal women who have dry eye and those who do not. Their results showed that postmenopausal women with dry eye have significantly thinner corneas than postmenopausal women with no dry eye.
“Some authors have detected decreases in corneal thickness values with each decade of life,” the study authors said. “We believe that a longer duration of dry eye symptoms may be the cause of the reduced corneal thickness values found in older postmenopausal women.”
Study overview
Keratoconjunctivitis sicca is associated with dryness of other mucoses. It can be observed with some systemic diseases. Image: The Atlas of Ophthalmology Photo CD, SLACK Incorporated |
The corneal thicknesses of 30 postmenopausal women with dry eye and 32 postmenopausal women without dry eye were measured with the Bausch & Lomb Orbscan II topography system.
Each woman answered a questionnaire and also underwent a tear breakup time test, Schirmer testing, fluorescein staining of the cornea and an analysis of the meibomian gland by slit lamp along with the corneal thickness measurement.
The participants in the study were myopic women who had reached menopause naturally, did not have a history of wearing contact lenses, were nonsmokers, were generally sedentary and were not taking medication.
Dry vs. normal
Following the tests, the postmenopausal women were divided into two subgroups, a dry eye group and a normal group.
In this study, dry eye was defined as having at least two positive results out of several tests: tear film breakup time of less than 10 seconds, Schirmer basal tear secretion test score of less than 5 mm, fluorescein score of more than 1 on a scale of 0 to 3, and existence of meibomian gland disease greater than 1 on a scale of 0 to 3.
Patients were considered normal if they had normal values in the tear breakup test, fluorescein staining of the cornea and analysis of the meibomian gland, but had Schirmer test results that were less than 5 mm.
Measuring corneal thickness
Corneal thickness values were measured for each patient 1 week following the dry eye tests using the Orbscan II, which measures anterior and posterior corneal elevations, surface curvature and corneal thickness.
The measurements were taken between 10 a.m. and 11 a.m. to avoid changes resulting from diurnal variations.
The authors found that the mean corneal thickness values at each location were significantly reduced in dry eyes compared to normal eyes.
One of the factors that may lead to decreased corneal thickness values may be an increase in tear film evaporation resulting in increased osmolarity of the tear fluid, according to the study authors. Tear turnover may also result in an increase in osmolarity.
Special attention needed
The authors said it seems that hormones play a role in dry eye because higher estrogen levels in postmenopausal women were associated with decreased tear function.
“The same seems to happen with corneal thickness values because rises in estrogen seem to induce increases in corneal thickness values,” the authors said. “Theoretically, if higher estrogen levels can induce decreased tear function, it may cause dry eye and subsequently reduced corneal values.”
Special considerations should be made for postmenopausal women with dry eye who want to undergo LASIK, the authors said. Preoperative assessment of corneal thickness values could help avoid possible risks of postoperative keratectasia following LASIK, they said.
Further research is needed to determine if hormone replacement therapy could help avoid the reduction of corneal thickness values in postmenopausal women, they concluded.
For Your Information:Reference:
- Juan Alberto Sanchis-Gimeno, MD, PhD, can be reached at apartado de correos 15038, Valencia, 46080, Spain; e-mail: juan.sanchis@uv.es. Dr. Sanchis-Gimeno and colleagues have no direct financial interest in the products mentioned in this article, nor are they paid consultants for any companies mentioned.
- Sanchis-Gimeno JA, Lleo-Perez A, et al. Reduced corneal thickness values in postmenopausal women with dry eye. Cornea. 2005;24(1):39-44.
- Daniele Cruz is an OSN Staff Writer who covers all aspects of ophthalmology.