[Influence of pregnancy on refractive parameters after LASIK surgery]

Objectives: Different ocular changes and complications of refractive surgery such as photorefractive keratectomy (PRK) due to pregnancy have been described in the last few years. However there is no information about the possible problems of laser in situ keratomileusis (LASIK) in pregnant women. Our objective was to study how physiological changes secondary to pregnancy could alter the refractive situation in pregnant women who have undergone LASIK surgery. We show the results obtained due to the changes between the first two trimesters of the pregnancy.

Methods: A prospective and observational study was conducted in which one study group, made up of 9 patients who had undergone LASIK surgery before becoming pregnant, was compared with a control group of 9 patients with non-surgically corrected refractive problems. The following measurements were made in both groups in the first and second trimesters of the pregnancy; visual acuity, the best corrected visual acuity, tonometry, ocular anatomical characteristics by biometry, and refractive and corneal study by Pentacam(®).

Results: Signicant changes were observed in the cylinder and spherical equivalent between the two trimesters in both groups. Visual acuity and spherical equivalent show a strong trend towards worsening, which was more significant in the study group. The patients of this group who had a larger pre-surgical defect showed lower modifications during the six first months of pregnancy.

Conclusions: The majority of women who require laser refractive surgery are are between 20-30 years old, thus in many cases corneal surgery is followed by at least one pregnancy, with different possible ophthalmological effects. The conclusions that may be derived from this study are that the assessment of the refractive changes in surgically operated corneas may be biomechanically weakened on being subjected to physiological hormone stimulation as happens during gestation.