Retinal Nerve Fiber Layer and Macular Thickness Changes During Pregnancy

Retinal Nerve Fiber Layer and Macular Thickness Changes During Pregnancy by Optical Coherence Tomography: Prospective, Observational, Nonrandomized Controlled Study

Purpose:

Primary: to prospectively measure Retinal Nerve Fiber Layer (RNFL) and macular thickness changes during pregnancy by Optical coherence tomography

Secondary: The effect of pregnancy abnormalities on RNFL and macular thickness in participants who develop systemic or ocular complications during the study period.

There are several known ophthalmic physiologic changes in pregnancy:

1. Refractive Change: progesterone-mediated changes in fluid content partially accounts for refractive change of lens and cornea; myopic shift of less than 1 D was observed in in 15% of participating pregnant women
2. Night vision decreased mainly with low serum vitamin A levels in pregnant women.
3. Fall of the IOP in second half of pregnancy (about 10% drop)
4. Corneal changes (increased thickness; decreased sensitivity) = contact lens intolerance

The retina and optic nerve are considered part of central nervous system, the retina and choroid are highly vascularized. Due to changes in CSF and brain volume, vascular and fluid changes all over the pregnant woman's body we expect to find changes in RNFL and macular thickness during pregnancy.

Inclusion Criteria:

• 1st trimester (6-14w) pregnant healthy women
• No known medical problems related to their current pregnancy on recruitment
• Age 18-45yrs
• No known retinal or optic nerve disease
• Refraction between +3.0 and -4.0 diopters
• Agrees to participate in the study

Exclusion Criteria:

• Retinal or optic nerve disease
• Refractive errors more than +3.0 and -4.0.
• If already finished 14w gestation when recruited to the 1st OCT examination
• Known to have HTN or DM before gestation
• Ocular media abnormality that obscures OCT view or examination