Residual refractive error can lead to dissatisfaction following implantation of presbyopia correcting IOLs. Published studies analyzed the FineVision HP IOL, and the accuracy of hitting refractive targets. Table 2 shows the detailed values obtained. We can see that the mean postoperative SE values reported were close to emmetropia and never greater than a quarter of a diopter. Almost all the eyes from the different studies were within 1.00 D of SE. These studies involved follow-up periods from 1 month to 2 years, demonstrating the stability of the procedure. For the longer follow-ups the percentages for ±0.50 D were 75% (16) and 81.8% (17), being 100% for ±1.00 D (16, 17). The mean postoperative refractive cylinder values were also excellent with the main values being less than a quarter of a diopter and only two studies reporting about half a diopter (16, 23). Only Daya and Espinosa Lagana (19) (64 eyes at 6 weeks), Akahoshi (21, 22) (66 and 64 eyes at 3 months) and Bosc et al. (24) (36 eyes at 1–3 months) included the toric model in their cohorts, from 1.00 up to 5.25 D of cylinder. Specifically, in these studies, the accuracy for astigmatism correction was excellent: a cylinder value of ≤0.50 D for 93.40 to 95.45% of eyes, and ≤ 1.00 D in 100%. A high percentage of authors used the Barrett Universal II formula for the IOL power calculation (see Table 1 for a detailed description). A recent systematic review for IOL power calculation formulas concluded that, of all vergence formulas, this is currently the most often reported and most precise (25). A comparison of 12 formulas for the hydrophilic FineVision Micro F IOL in 172 eyes revealed that the Barrett Universal II formula provides excellent overall accuracy for eyes (86.55% ±0.50 D and a mean absolute error of 0.285 D), it being the most accurate for medium axial length eyes (26). The cohorts analyzed in our review mainly involved mean axial lengths about 23 mm, except for Japanese eyes which had longer values, around 25 mm (see Table 1). A questionnaire-based study conducted among members of the Japanese Society of Cataract and Refractive Surgery over the past 20 years revealed that the use of trifocal IOLs has particularly increased, and, in terms of IOL power calculations, the Barrett Universal II formula has been gaining popularity when there is no post-laser vision correction (27). We should therefore consider that the use of this formula with the FineVision HP IOL provides excellent refractive outcomes. However, it should be noted that some authors have used other formulas, such as the SRK/T, Haigis, Hoffer Q, or Holladay 2, for example, also reporting good refractive accuracy. For this reason, we believe that surgeons should consider applying these popular formulas to calculate the IOL power. To make a comparison with other trifocal IOLs, it is interesting to discuss the outcomes published recently in a systematic review and meta-analysis of 22 studies reporting data for trifocal and EDOF IOLs (2). This study considered publications reporting on the FineVision, the AcrySof IQ PanOptix (Alcon Labs, Fort Worth, USA), and the AT LISA tri (Carl Zeiss Meditec, Jena, Germany) IOLs; here the mean SE postoperative outcomes reported varied from −0.39 to 0.25 D, values which are in agreement with the mean SE values found in the FineVision HP IOL studies (Table 2).

Rotational stability was only reported by Daya and Espinosa Lagana (19), who showed a mean IOL rotation of 5.84 ± 6.41° from the intented axis of implantation, noted on the operative form, to the orientation of the lens on internal aberrometry (implied rotation) at the last postoperative visit (6 weeks). 38 eyes (61.3%) were within 5° of the intended orientation, 18 (29%) were between 6 and 10°, and 6 (9.7%) were more than 10° away from the intended axis. As these authors discussed, this method is not as accurate as directly observing the IOL’s position with a dilated pupil, as it is highly dependent on the quality of the test performed and prone to error from IOL tilt. Based on the good refractive cylindrical outcomes in that cohort, the authors suggested that in reality there was minimal, if any, cylindrical correction efficacy reduction in spite of the slightly higher rotation value found. The method used may be the source of this rotation value. Other studies, using the same platform with the hydrophilic version of the lens (FineVision POD FT IOL) reported better rotational stability outcomes. For example, Vandekerckhove (28), using images captured from a camera for 37 eyes, indicated mean values of 2.56 ± 2.22° and 2.55 ± 2.62° at 6 and 12 months postoperatively, respectively; and Ang (29), using a slit lamp on 187 eyes, found mean values of 1.77 ± 1.82°, 1.83 ± 1.85°, and 2.00 ± 2.42°, at 4 to 6 months, 11 to 13 months, and 21 to 26 months postoperatively, respectively. Furthermore, Ruiz-Mesa et al. (30), using this model in eyes with high levels of corneal astigmatism (cylindrical IOL power of 3.75 D or greater), with the longest follow-up period (5 years), found no significant rotation in their cohort. It is therefore expected that the toric version of the FineVision HP IOL will demonstrate good rotational stability.

As mentioned in the results section, visual acuity was evaluated in all the studies analyzed. It should be considered that for trifocal lenses, in addition to distance visual acuity, intermediate and near visual acuities should be measured in order to determine how these lenses provide good visual acuity at different distances. All the studies detailed in Table 3 reported CDVA values, in almost all cases these being better than 20/20. Also, almost all the studies provided UDVA outcomes, which were also good. It should be noted that the Bayesian network meta-analysis comparing the outcomes of different presbyopia-correcting IOLs frequently used in clinical practice found that, for UDVA, all multifocal IOLs were comparable with monofocal IOLs (1). The systematic review and meta-analysis by Karam et al. (2) of several trifocal IOLs showed mean UDVA values ranging from −0.12 to 0.11 logMAR, and mean CDVA values ranging from −0.2 to 0.06 logMAR, these being similar to those reported in this review (see Table 3). The outcomes for the FineVision HP IOL at far distance were stable both in the short-term (1 month) (9, 12, 13, 24) and long-term (24 months) (16, 17). For other distances, the visual acuity can be measured at different optotype locations. Table 3 shows that monocular UIVA and DCIVA was measured at 80, 70, 66 and 60 cm in different clinical studies; it was usually measured at 80 and 70 cm, with DCIVA values ranging from 0.02 (15) to 0.19 (21) logMAR at 80 cm (about 20/20 to 20/32), and from −0.03 (13) to 0.12 (23) logMAR at 70 cm (about 20/20 to 20/25). None of the studies analyzed the intermediate visual acuity at different distances; however, if we make a comparison, it seems that better outcomes were found for 70 cm compared to 80 cm. Monocular UIVA measured at 60 cm was also close to 20/20 (0.03 logMAR) (19). This tendency is related to the intermediate focus created by the IOL (+1.75 D). For near vision, a monocular DCNVA at both 40 cm and 35 cm was good, ranging from 0.02 (21) to 0.20 (18) logMAR (about 20/20 to 20/32), and from 0.12 (23) to −0.04 logMAR (13), respectively (about 20/20 to 20/25). Again, the better outcomes for closer distances are related to the near focus of the IOL (+3.50 D). It should be noted that, in general, distance visual acuity was good, better than or equal to 20/20, and both intermediate and near vision were quite similar, maintaining a high level, ranging from 20/20 to 20/32. Karam et al. (2) reported similar outcomes, with mean UIVA values ranging from −0.01 to 0.29 logMAR, and a mean DCIVA ranging from 0.006 to 0.24 logMAR. For near vision, those authors found a mean UNVA ranging from −0.03 to 0.18 logMAR, and a mean DCNVA ranging from 0.06 to 0.19 logMAR.

Mean visual acuity values correlate with cumulative visual acuity outcomes. Table 4 shows the percentages for monocular and, in some studies, binocular visual acuity at different distances. Note that the percentages for ≥20/20 (0 logMAR) are, in most cases, between about 90 and 100% for CDVA. As expected, slightly lower values than for CDVA are found for DCIVA at 80, 70 and 66 cm, and for DCNVA at both 40 and 35 cm. However, these values show that this lens offers good outcomes for intermediate and near vision. For example, Ang (16) and Khoramnia et al. (17), with the longest follow-up periods (2 years) showed similar binocular cumulative visual acuity values: about 60, 90, and 100% for ≥20/20 (0 logMAR), ≥20/25 (0.1 logMAR), and ≥ 20/32 (0.2 logMAR), respectively, at 70 cm, this being similar at 35 cm. Therefore, in terms of visual acuity performance this lens provides excellent vision at far distances, and good vision for intermediate and near distances.

In relation to the defocus curve, which is an excellent metric for determining the visual performance of our patients at different vergences (distances), we have created Table 5 to show the diopter range in which patients show a visual acuity of ≥20/32 (0.2 logMAR). Note that these values were estimated from the defocus curves depicted by authors in their respective publications. This range give us a detailed value of the useful range of vision provided by this lens. In general, the defocus curves for this lens show a peak of visual acuity for distance vision (0 D of defocus, vergence), followed by a smooth reduction as negative vergence increases in value (negative defocus values) up to another peak located in near vision (about −2.5 D of defocus). The ranges obtained in Table 5, which can be defined as the depth-of-focus of the lens, reveal that this is between 3.00 to 4.00 D under monocular conditions (7, 8, 14, 18) to 4.25 to 5.00 D under binocular conditions (13, 15–17, 23, 24). This depth-of-focus increases about 1 D more for binocular conditions, which is the reality in day-to-day activities for our patients. Kim et al. (14) used a mix-and-match technique combining the FineVision HP IOL with the FineVision Triumf IOL obtaining a depth-of-focus under binocular conditions of 4.25 D, which is slightly lower than the value obtained under binocular conditions when implanted with bilateral FineVision HP IOLs (4.50/4.75 D). We therefore consider that bilateral implantation of the FineVision HP IOL is the best approach, providing a continuum of visual acuity at far, intermediate and near distances.

Vinas et al. (9) measured the LCA of the FineVision HP IOL using psychophysical methods. These authors aimed to provide insights into how the material of the lens and its multifocal design influenced the LCA of 20 implanted eyes. They found that the LCA was significantly higher for far vision than for intermediate and near vision (p < 0.05), and slightly higher for the hydrophobic lens than for the hydrophilic counterpart at far distances. Poyales et al. (10) recorded some optical metrics, such as the MTF, Strehl Ratio and HOAs, at 3 months post-surgery; when comparing the hydrophilic and hydrophobic FineVision IOLs they found that the MTF (25.14 versus 26.48) and Strehl Ratio (0.15 versus 0.16) were close to that of a normal population, and the tilt (0.24 versus 0.33 μm), HOAs (0.27 versus 0.40 μm) and spherical aberration (0.28 versus 0.26 μm) were similar for the two IOLs. In another study, Danzinger et al. (18) measured internal HOAs and compared the FineVision HP IOL with the Isopure IOL. These authors found that at a 5 mm pupil eyes implanted with the FineVision HP had significantly lower HOAs values (FineVision HP: 0.33 ± 0.10 μm; Isopure: 0.57 ± 0.11 μm; p < 0.01) with significantly increased negative spherical aberration in the Isopure eyes (Isopure: −0.40 ± 0.09 μm; FineVision HP: −0.05 ± 0.08 μm; p < 0.01). With a smaller pupil, 3 mm, the outcomes showed comparable HOAs in the two groups (Isopure: 0.18 ± 0.10 μm; FineVision HP: 0.14 ± 0.07 μm; p = 0.107) with a small but significantly greater negative spherical aberration in the Isopure eyes (Isopure: −0.04 ± 0.04 μm; FineVision HP: −0.02 ± 0.02 μm; p < 0.01). The increased spherical aberration value in the Isopure eyes correlates with the design of this surface which has been shown to differ from an aspheric monofocal lens (31). Note that Shack-Hartmann technology presents some problems testing diffractive IOLs (32) and the results might not be compared with that of non-diffractive IOLs.

It is considered that contrast sensitivity function assessment is the best parameter for measuring spatial vision limits, providing information about visual performance for a range of object scales. Its measurement under different lighting conditions, mainly photopic and mesopic, can inform us about the vision of our patients in these circumstances. Superimposed images due to multifocality (in-focus and out-of-focus images) may result in a reduced-contrast retinal image and, therefore, lower contrast sensitivity (33). Several studies have recorded the contrast sensitivity at different spatial frequencies after implantation of FineVision HP IOLs. Figure 2 shows the estimated curves obtained from the graphs published under photopic (top: 2A, 85 cd/m²) and mesopic (bottom: 2B, 3.5 or 3 cd/m²) conditions in these studies (7, 8, 10, 13, 15–17, 23). This figure also illustrates mean binocular contrast sensitivity in patients implanted with monofocal IOLs (33) and monocular mean values for normal patients in the 50–75 year age range (mean 63.9 years) (34) for comparison. As can be seen, the reported outcomes were good, especially in those studies where binocular measurements were taken and there were longer-follow-up periods compared to the monofocal IOLs and the normally sighted groups. Cao et al. (35), in their meta-analysis of 21 randomized controlled trials involving 2,951 subjects, observed lower contrast sensitivity in multifocal IOL patients; however, they indicated that the gap between these patients and those implanted with monofocal lenses was only 0.06 units, meaning the disadvantage of multifocal IOLs in terms of contrast sensitivity is not very great. The outcomes found here agree with that statement. It is interesting to note that in studies with longer follow-up periods better outcomes were found for all spatial frequencies and both illumination conditions (from 6 to 24 months). Indeed, it has been reported that the typical neuroadaptation process after multifocal IOL implantation is at least 3 months in terms of significantly reducing photic phenomena (36), and the maximum improvement is likely to be reached 12 months after surgery (37). We may observe a reduction in contrast sensitivity under mesopic conditions, particularly at higher spatial frequencies. This behavior agrees with classic data on the effect of luminance level on contrast sensitivity (38). In addition, it has been published that contrast sensitivity function might be significantly affected due to the light division that occurs in multifocal IOLs, especially in low-mesopic environments (36).

Martínez de Carneros-Llorente et al. (8), Poyales et al. (10), Benyoussef et al. (13), Akahoshi (22) and Nagy et al. (23) used the NEI VFQ-25 questionnaire with their cohorts, reporting high scores for the different questions analyzed, mainly distance and near activities (Figure 3). The maximum score value was 100 and all the questions related to vision were around 80 or above in all the studies. Other studies involving the hydrophilic version of this lens reported similar outcomes: the median sub-score values were ≥ 80 for general, near and far vision, and driving 3 months post-surgery (39); mean values of 93.64 ± 4.16, 91.00 ± 13.78, 89.44 ± 13.54, 83.88 ± 14.95, and 89.76 ± 20.14 were reported for overall satisfaction, general vision, far activities, near activities, and driving, respectively, 6 months post-surgery (40). Poyales et al. (10) also evaluated the hydrophilic lens and found comparable outcomes (p > 0.05): 84.2, 89.9, and 93.8 mean values for general vision, near and distance activities, respectively. Martínez de Carneros-Llorente et al. (8) in their study also compared the outcomes of the FineVision HP IOL with two other trifocal IOLs, the AT LISA tri 839MP and the AcrySof IQ PanOptix. They found no statistically significant differences for any of the items on the questionnaire (p > 0.07), and considered that, independent of the IOL implanted, patient satisfaction was high. As indicated in the results section, Akahoshi (22) administered two other questionnaires to their sample. Using the Catquest-9SF, he found that 90.57% of patients reported no sight difficulties in their everyday-life, and all of them were “very or quite satisfied” with their sight. According to the PRSIQ outcomes, 98.11 and 98.11% of patients did not need glasses or contacts for far, intermediate and near vision, respectively. He concluded that patients bilaterally implanted with this IOL had high vision and health-related quality-of-life scores, with a high spectacle-independence rate and high patient satisfaction. The self-assessment questionnaire used by Ang (16), Khoramnia et al. (17) and Nagy et al. (23) 3 months post-surgery revealed that the use of glasses for distance, intermediate and near vision was very low (Figure 4). Indeed, for near vision a high percentage of the patients in the three studies reported using glasses “none of the time.” The general satisfaction level indicated that all the patients in the Ang (16) cohort, 82.3% in the Khoramnia et al. (17) sample and 88% in the Nagy et al. (23) were “very satisfied” and/or “satisfied.” Similarly, 100, 78.5 and 96% of patients answered “definitely yes” and/or “probably yes,” respectively, when asked whether they would choose the same IOL model again. Also, 100, 80.4 and 96%, respectively, would recommend this IOL to a friend or family member. In general, in line with the different PROQ outcomes published, we consider that this lens offers generally satisfying results in terms of performing everyday tasks.

The possible increase in photic phenomena after multifocal IOL implantation is a factor that should be kept in mind. Poyales et al. (10) studied halometry 3 months post-surgery and their results showed that the lens appeared not to introduce any additional problems to those reported for multifocal diffractive designs. They stated that 3 patients reported negative dysphotopsia on day 1 post-surgery but did not report this after 1 month. Khoramnia et al. (16), at a longer follow-up period (6 months), measured the size and intensity of the photic phenomena on a scale from 0 to 100, with halo size, halo intensity, glare size, and glare intensity being 46, 50.3, 13.1 and 22.8, respectively. They compared the IOL with its hydrophilic counterpart and found no statistically significant differences (p > 0.2). Low glare and halo values did not hinder the majority of the activities that patients carry out daily (18). However, we consider that further studies should be carried out to fully analyze photic phenomena.

Only 3 studies reported adverse events in their sample, these being dry eye in two eyes, a posterior vitreous detachment in one eye, a capsular phimosis in another eye, one macular edema and one corneal edema. The presence of glistening was not indicated by any of the different authors in the publications analyzed.