Pregnancy
Conditions
Keywords
Cornea, biomechanics, pregnancy, keratoconus, refractive surgery
Brief summary
The intraocular pressure in the human bulbus requires that the wall of the eye shows a certain (bio)mechanical strength. The human cornea represents the anterior portion of this wall. Since several years, there is a growing interest in the ophthalmological community for identifying factors modulating the biomechanical stability of the human cornea. Reasons are twofold: advances in keratoconus research and the increasing numbers of refractive laser surgery procedures with (correspondingly) increasing numbers of complications due to non-respecting the limits of corneal biomechanics. There is evidence that oestrogen, but also thyroïd hormone changes have a major impact on corneal biomechanics. A number of recent observational studies have reported on keratoconus and refractive laser surgery patients with decompensating biomechanics during pregnancy. Both hormones also show physiological changes during pregnancy and little is known about the impact of these physiological changes on the human cornea. The aim of this study is to establish baseline values for physiological changes in the human cornea during pregnancy.
Interventions
DEVICEOcular Response Analyzer
To measure corneal biomechanics, specifically corneal hysteresis (CH) and the Corneal Resistance Factor (CRF). The devise measures in a non-contact manner, by analyzing the deformation of the cornea upon a defined pulse of air.
DEVICEScheimpflug measurement
A Scheimpflug camera will be used in a non-contact manner to assess topographical data from the anterior and posterior corneal surface as well as detailed data on corneal thickness.
OTHERBlood sample
A blood sample will be taken at 6 months after surgery to determine the levels of several hormones. The blood needed to détermine hormone levels during pregnancy will be acquired during the routine examinations that are performed during pregnancy. Here, blood is taken routinely and an additional volume is taken for the purpose of this study.
Sponsors
University Hospital, Geneva
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Older than 18 years * Pregnancy confirmed by echography * Before gestation week 14
Exclusion criteria
* Pre-existing corneal disease * Previous eye surgery * Inability to understand the nature of the study * Patient with legal guardian
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlate oestradiol and TSH plasma changes with changes in corneal CRF and CH and topographical changes | 15 months | 3 examinations during pregnancy (gestation week 10-14, 20-26, and 36-40) and one visit at 6 months after pregnancy |
Countries
Switzerland
Outcome results
None listed