Tilt and decentration of intraocular lenses (IOL) may occur secondary to a complicated cataract surgery or following an uneventful phacoemulsification. Although up to 2–3° tilt and a 0.2–0.3 mm decentration are common and clinically unnoticed for any design of IOL, larger extent of tilt and decentration has a negative impact on the optical performance and subsequently, the patients’ satisfaction. This negative impact does not affect various types of IOLs equally. In this paper we review the methods of measuring IOL tilt and decentration and focus on the effect of IOL tilt and decentration on visual function, in particular visual acuity, dysphotopsia, and wavefront aberrations. Our review found that the methods to measure the IOL displacement have significantly evolved and the available studies have employed different methods in their measurement, while comparability of these methods is questionable. There has been no universal reference point and axis to measure the IOL displacement between different studies. A remarkably high variety and brands of IOLs are used in various studies and occasionally, opposite results are noticed when two different brands of a same design were compared against another IOL design in two studies. We conclude that <5° of inferotemporal tilt is common in both crystalline lenses and IOLs with a correlation between pre- and postoperative lens tilt. IOL tilt has been noticed more frequently with scleral fixated compared with in-the-bag IOLs. IOL decentration has a greater impact than tilt on reduction of visual acuity. There was no correlation between IOL tilt and decentration and dysphotopsia. The advantages of aspheric IOLs are lost when decentration is >0.5 mm. The effect of IOL displacement on visual function is more pronounced in aberration correcting IOLs compared to spherical and standard non-aberration correcting aspherical IOLs and in multifocal versus monofocal IOLs. Internal coma has been frequently associated with IOL tilt and decentration, and this increases with pupil size. There is no correlation between spherical aberration and IOL tilt or decentration. Although IOL tilt produces significant impact on visual outcome in toric IOLs, these lenses are more sensitive to rotation compared to tilt.

PURPOSE: To compare uniocular and binocular visual acuity, wavefront aberrations, and defocus curves using the TECNIS Eyhance (Johnson & Johnson) and RayOne (Rayner) intraocular lenses (IOLs). METHODS: In this prospective, randomized, comparative study, 50 patients (100 eyes) were randomized to receive the same IOL bilaterally ( ClinicalTrials.gov Identifier: NCT04175951). Follow-up visits were at 1 and 3 to 9 months postoperatively. Primary outcome measures were uncorrected distance (UDVA) and uncorrected intermediate (UIVA) visual acuity (logMAR) at 66 cm. Secondary outcome measures were corrected distance (CDVA) and distance-corrected intermediate (DCIVA) visual acuity at 66 cm, manifest refraction, spherical (Z 4 0 ) and vertical coma (Z 3 −1 ) aberrations (total, internal eye, and corneal) at normal pupil size, defocus curves, and Catquest 9SF and Glare and Halos questionnaire on Likert scale (1 = no glare and halos and 4 = continuous). RESULTS: Uniocular UDVA ( P = .02), UIVA ( P = .02), and binocular UIVA ( P < .01) and uniocular ( P = .01) and binocular ( P < .01) DCIVA were better with the TECNIS Eyhance IOL at 3 to 9 months. At 3 to 9 months, both uniocular and binocular defocus curves were significantly broader with the TECNIS Eyhance IOL between −0.50 and −3.00 diopters (D). For total and internal eye, there was a statistically but clinically insignificant difference in Z 4 0 with the TECNIS Eyhance IOL. Rasch scores improved (TECNIS Eyhance: 2.04 ± 1.34 to 2.91 ± 0.81 and RayOne:1.61 ± 1.35 to 2.97 ± 0.16) at 3 to 9 months. Refraction, Z 3 −1 , glare, and halos were not different. CONCLUSIONS: The TECNIS Eyhance IOL provided better DCIVA and broader defocus curves than the RayOne IOL. There was no difference in CDVA or patient-reported outcomes. Although there were some differences in aberrations when measured with normal pupil size, they were not clinically significant. [ J Refract Surg . 2022;38(1):10–20.]

AimTo compare intraocular lens (IOL) calculation methods not requiring refraction data prior to myopic laser-assisted in situ keratomileusis (LASIK) and radial keratotomy (RK).MethodsIn post-LASIK eyes, the methods not requiring prior refraction data were Hagis-L; Shammas; Barrett True-K no-history; Wang-Koch-Maloney; ‘average’, ‘minimum’ and ‘maximum’ IOL power on the American Society of Cataract and Refractive Surgeons (ASCRS) IOL calculator. Double-K method and Barrett True-K no-history, ‘average’, ‘minimum’ and ‘maximum’ IOL power on ASCRS IOL calculator were evaluated in post-RK eyes. The predicted IOL power was calculated with each method using the manifest postoperative refraction. Arithmetic and absolute IOL prediction errors (PE) (implanted–predicted IOL powers), variances in arithmetic IOL PE and percentage of eyes within ±0.50 and ±1.00 D of refractive PE were calculated.ResultsArithmetic or absolute IOL PE were not significantly different between the methods in post-LASIK and post-RK eyes. In post-LASIK eyes, ‘average’ showed the highest and ‘minimum’ showed the least variance, whereas ‘average’ and ‘minimum’ had highest percentage of eyes within ±0.5 D and ‘minimum’ had the highest percentage of eyes within ±1.0 D. In the post-RK eyes, ‘minimum’ had highest variance, and ‘average’ had the least variance and highest percentage of eyes within ±0.5 D and ±1.0 D.ConclusionIn post-LASIK and post-RK eyes, there are no significant differences in IOL PE between the methods not requiring prior refraction data. ‘Minimum’ showed least variance in PEs and more chances of eyes to be within ±1.0 D postoperatively in post-LASIK eyes. ‘Average’ had least variance and more chance of eyes within ±1.0 D in post-RK eyes.

Purpose: To evaluate whether phacoemulsification is an aerosol-generating procedure in an ex vivo experimental model. Setting: Sussex Eye Hospital, Brighton, United Kingdom. Design: Experimental study. Methods: In this ex vivo study on 15 porcine eyes, an optical particle counter was used to measure particles of 10 µm and less using the cumulative mode based on the 6 in-built channel sizes. The 2 parts of the study were to: (1) assess the efficacy of the particle counter in the theater environment where there are dynamic changes in temperature and humidity; and (2) to measure aerosol generation with 3 phacoemulsification settings: (i) continuous power with 80% longitudinal (5 eyes); (ii) continuous power with 100% torsional (5 eyes); and (iii) continuous power with 80% longitudinal with application of hydroxypropyl methylcellulose (HPMC) on the ocular surface (5 eyes). Five measurements were taken prephacoemulsification and 5 during phacoemulsification per eye therefore totaling 75 measurements. Results: Maximum aerosols were captured when the counter faced the aerosol source. There was no significant difference in aerosol generation of all sizes during each phacoemulsification setting with torsional, longitudinal, and longitudinal with HPMC (P > .01). Combining data of all 3 phacoemulsification settings (150 measurements from 15 eyes), there was no significant difference comparing prephacoemulsification and during phacoemulsification for aerosols of 5 µm or less (1455 vs 1363.85, P = .60), more than 5 to 10 μm (1.5 vs 1.03, P = .43), and of 10 µm or less (1209 vs 1131.55, P = .60). Conclusions: Phacoemulsification did not generate aerosols of 10 μm or less with continuous power using 80% longitudinal, 100% torsional, and 80% longitudinal setting with HPMC on the surface.