Purpose To compare functional outcomes of Wavelight Allegretto Eye-Q 400Hz and Schwind Amaris 750S excimer laser for astigmatism between 2 and 7 diopters(D). Methods Prospective comparative non-randomized case series of 480 eyes assigned in two laser groups and further divided into myopic and mixed astigmatism subgroups. All treatments were centered on corneal vertex. One-year results were compared between the groups. Statistical analysis was performed using z-test. Results Both Allegretto and Amaris postoperative uncorrected distance visual acuity (UDVA) improved in comparison to preoperative corrected distance visual acuity (CDVA). The difference was significant in the Allegretto group for myopic astigmatism (p=0.017). There was no difference in postoperative UDVA between lasers. Average sphere decreased in all groups for both lasers (p<0.001) without difference in effectiveness of spherical correction between lasers for both groups. In Allegretto, average cylinder decreased from −3.30D to −0.55D in myopic astigmatism (p<0.001) and from −3.84D to −0.85D in mixed astigmatism (p<0.001). In Amaris average cylinder decreased from −3.21D to −0.43D in myopic astigmatism (p<0.001) and from −3.66D to −0.58D in mixed astigmatism (p<0.001). Amaris group had less residual astigmatism (myopic astigmatism p= 0.023, mixed astigmatism p<0.001). Mean spherical aberration shifted from positive to negative in mixed astigmatism for both lasers. Conclusion Both lasers are effective in terms of UDVA, CDVA, spherical correction, and preservation of high-order aberrations. However, Amaris was more effective in cylinder correction.

Both Verisyse and Veriflex pIOLs are effective in correcting myopia. The Veriflex lens demonstrated better refractive outcome; however, subclinical inflammation observed in the Veriflex group and potential influence of inflammation on ECC loss require further investigation.

The predicted SIA power was up to 12% less than expected in cases of -6.00 diopters cylinder treated for myopic astigmatism using the Allegretto platform. The mean predicted angle of error (the angle between the SIA and TIA axes) was less than 4°, increasing to 12° for against-the-rule astigmatism. The Allegretto platform tended toward a clockwise axis rotational error, whereas the Amaris platform tended toward the opposite. [J Refract Surg. 2017;33(2):104-109.].

Accurate biometry, appropriate intraocular lens (IOL) power formula, and modern techniques are very important for cataract surgery as a refractive procedure aiming at the intended refractive result. Main sources of postoperative refractive surprise are errors in biometry, such as, inaccurate preoperative measurements (axial length [AL] or keratometry), IOL calculation formula, IOL insertion, and lens constant's errors [1]. Other common reasons for 'wrong' IOL implantation as reported by Steeples in their study of 178 cases are: inaccurate biometry, wrong IOL selection, transcription errors, handwriting misinterpretations, change in list order, right/left eye confusion, patient identification issues, misfiled biometry, wrong IOL written on theater white board, optimal IOL power unavailable in stock, wrong IOL power implantation after complicated surgery, wrong patient notes, communication errors, or-as in the case presented hereinan IOL mislabeled by the manufacturer [2]. In case of a refractive surprise following cataract surgery, identification of the failure cause will lead us to an optimal solution. Corneal irregularities, long-term history of contact lens use, superficial punctate keratitis, posterior capsular opacity, decentered IOL, preoperative inaccurate measurement, implantation of the wrong IOL, intraoperative possible upside-down implantation, or fundus problems have to be excluded [3]. Corneal topography and corneal tomography often provide the best overall assessment of the corneal status and degree of astigmatism, irregularity, and symmetry, and

Wavelight Allegretto 400Hz and Schwind Amaris 750S showed excellent results for treating patients with astigmatism, regardless whether it is mixed or myopic astigmatism. The J45 did not reduce significantly possibly because of the low number of eyes with oblique astigmatism. There was no genuine difference post-operatively between groups treated on two different laser platforms according to the vector analyses.