Comparative Study of Corneal Thickness before and after FemtoLasik Surgery with Pentacam® AXL and Ultrasound Device (Tomey SP-100)

Aims: The purpose of our research is to evaluate corneal thickness, pre-operative and post-operatively after FemtoLasik surgery, using “Pentacam® AXL” and Ultrasound device. To evaluate the correlation of the two devices and their interchangeability.

Sample and Study Design: Our data includes 70 eyes of patients, age 19- 59 years, who undergone Lasik surgery for myopia. The data concerned pre-operative and post-operative central corneal pachymetry using Ultrasound pachymeter (Tomey SP-100) and “Pentacam® AXL”.

Methodology - Place and Duration of Study: University of West Attica Dept Biomedical Science Course Optics & Optometry in collaboration with Private Ophthalmology Clinic “Athens Opthalologiko” during the period between May 2018 until September 2018. In this study, a comparison of data taken with Pentacam and Ultrasound was performed concerning central corneal thickness before and after FemtoLasik to evaluate the correlation of these devices. All the FemtoLasik surgeries were performed by the same experienced surgeon in order to ensure good repeatability of surgical procedures and all the patients selected had healthy eyes with no other ophthalmic pathology or systemic disease and myopia ranging from -1.00 to 9.25 Diopters. All patients were measured one month after FemtoLasik having achieved 6/6 visual acuity.

Results: Central corneal thickness before FemtoLasik measured by ultrasound device had an arithmetic mean value of 552.43 μm ± SD 26.95. The thickness preoperatively with “Pentacam” had an arithmetic mean value of 556.26 μm ± SD 27.82. The corneal thickness after Lasik measured by ultrasound device had an arithmetic mean value of 493.21μm ± SD 36.30, while for “Pentacam” the arithmetic mean value was 499.07μm ± SD 36.17. The two devices correlate strongly (0.9218 and 0.9986 respectively with significant level P<0,0001)

Conclusion: Our conclusions after statistical analysis are that Ultrasound pachymetry and “Pentacam” topography correlated strong.