Comparison Of Wavefront Aberrations With Two Aberrometers: Zywave® Vs. Peramis®

To compare lower and higher order aberrations (HOA) and wavefront refractometry measurements between Zywave^® and PERAMIS^®, in refractive surgery candidates.

^{Eye Research Center, The Five Senses Health Institute, Moheb Kowsar Hospital, Iran University of Medical Sciences, Tehran, Iran}

203 consecutive patients were studied. Inclusion criteria were age ≥ 18 years old, ≤ 8 D myopia, ≤ 6 D hyperopia and ≤ 6 D astigmatism.   A thorough comprehensive ophthalmic examination, corneal tomography by Orbsan^®, and ocular wavefront aberrometry were performed for all patients.The degree of agreement between measurements was evaluated by intra class correlation (ICC).

188 eyes of 188 patients were studied. In terms of wavefront refractometry, high degree of agreement was found between sphere, cylinder and cylinder axis measured by Zywave^® and PERAMIS^® (ICCs were 0.97, 0.97 and 0.7 respectively). The degree of agreement between total root mean square (RMS) measured by Zywave^® and ocular total RMS measured by PERAMIS^® was high (ICC=0.9). The ICC for measurement of higher order aberration (HOA) RMS, vertical coma RMS, vertical trefoil RMS and spherical aberration RMS by Zywave^® and PERAMIS^® was 0.64, 0.6, 0.5 and 0.58 respectively, which are considered as low degree of agreement.

Zywave^® and PERAMIS^® showed a high level of agreement in wavefront refractometry and total wavefront measurements. Measurements of HOA are not interchangeable according to low levels of agreement found in the study.