Impact of Lens Material on Objective Refraction in Eyes with Trifocal Diffractive Intraocular Lenses

Effect of Monofocal, Wavefront-Shaped, and Diffractive Trifocal Intraocular Lenses on Scanning-Slit Automated Refraction

PURPOSE

To compare scanning-slit retinoscopy automated refraction spherical equivalent (ARSE) to subjective manifest refraction spherical equivalent (MRSE) in normal eyes with four different types of intraocular lenses (IOLs).

DESIGN

Retrospective cross-sectional study.

METHODS

A total of 279 pseudophakic eyes that underwent lens extraction at a private center with implantation of either a wavefront shaped IOL (Acrysof® Vivity, DFT015), a nonapodized diffractive trifocal IOL (Acrysof® Panoptix), or a monofocal IOL with negative spherical aberration (Tecnis ZCBOO) or aberration-free (Envista Mx60E). Patients who had an automated refraction measurement with retinoscopy refractometer and aberrometer (NIDEK OPD Scan III, Nidek Technologies) and subjective refraction data 1-2 months postoperatively were included in the study. Main outcome measured was the difference between automated refraction and subjective refraction.

RESULTS

Sixty-one eyes implanted with a DFT015 IOL, 78 eyes with a TFNT00 IOL, 40 with a ZCBOO IOL and 100 with a Mx60E IOL were enrolled in this study. Statistically significant myopic results were observed when using ARSE compared to MRSE in the DFT015 (-0.95 ± 0.64, -0.33 ± 0.65, P < .001), TFNT00 (-0.43 ± 0.36, -0.2 ± 0.35, P < .001), ZCBOO (-0.81 ± 0.63, -0.4 ± 0.69, P = .008) and Mx60E (-0.75 ± 0.65, -0.45 ± 0.52; P < .05) IOL groups. The absolute difference between the 2 methods was statistically significant in the DFT015 IOL group (0.65 ± 0.49; P < .05).

CONCLUSION

Automated refraction yields myopic results in pseudophakic eyes with monofocal and presbyopia correcting IOLs and may be used with caution. Manifest refraction "push-plus" technique should be used in all pseudophakic eyes to avoid over-minus prescriptions, especially in patient with residual refractive error following cataract surgery.

Hydrophobic Trifocal Toric Intraocular Lens Outcomes in Japanese Eyes After Cataract Surgery

Purpose

To analyze the refractive and visual outcomes following cataract surgery and implantation of a new hydrophobic trifocal toric intraocular lens (IOL) in Japanese eyes with different degrees of corneal astigmatism.

Methods

A total of 66 eyes from 39 patients implanted with a FineVision HP Toric IOL (Beaver-Visitec International Inc) were analyzed retrospectively. The main outcome measures considered were refraction, monocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), and distance-corrected intermediate visual acuity (DCIVA) at 80 and 66 cm, uncorrected near visual acuity (UNVA) and distance-corrected near visual acuity (DCNVA) at 40 cm. Eyes were evaluated at three months post-surgery.

Results

Sixty-five eyes (98.48%) were within ±0.50D of spherical equivalent, and all were within ±1.00D (mean: 0.00±0.21D). Moreover, 63 eyes (95.45%) had ≤0.50D of residual astigmatism, and all had ≤1.00D (mean: -0.08±0.23D). Similarly, 58 (87.88%) and 60 eyes (90.91%) had ≥20/20 UDVA and CDVA, respectively, with 65 (98.48%) and 66 eyes (100%) achieving ≥20/25 UDVA and CDVA, respectively. In addition, 28 (42.42%) and 23 eyes (34.85%) had ≥20/25 DCIVA at 80 and 66 cm, respectively, with 49 (74.24%) and 52 eyes (78.79%) achieving ≥20/32 DCIVA at 80 and 66 cm, respectively. Finally, 39 (59.09%) and 40 eyes (60.61%) had ≥20/20 UNVA and DCNVA, respectively, with 58 (87.88%) and 59 eyes (89.39%) achieving ≥20/25 UNVA and DCNVA, respectively.

Conclusion

Our study shows that implantation of the new hydrophobic FineVision HP Toric IOL results in accurate refractive outcomes, with good visual acuity at different distances, in Japanese eyes.

Refractive and Visual Outcomes Using a Trifocal, Diffractive, Hydrophobic Intraocular Lens in Japanese Eyes

Purpose

To report the refractive and visual outcomes after implantation of a trifocal, diffractive, hydrophobic intraocular lens (IOL) in Japanese eyes following cataract surgery.

Methods

A total of 45 eyes implanted with FineVision HP IOLs (Beaver-Visitec International, Inc. USA) were enrolled in this retrospective study. The clinical outcomes assessed after 3-months were refraction and monocular logarithm of the minimum angle of resolution (LogMAR) uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), distance-corrected intermediate visual acuity (DCIVA) at 80 and 66 cm, uncorrected near visual acuity (UNVA), and distance-corrected near visual acuity (DCNVA) at 40 cm.

Results

97.78% of the eyes were within ±0.50D of spherical equivalent and all of them were within ±1.00D (mean: -0.00±0.22 D, with 75.56% within ±0.13D), while 91.11% of the eyes had ≤0.50D residual astigmatism and all of them had ≤1.00D (mean: -0.08±0.24D, with 88.89% ≤0.25D). UDVA and CDVA showed mean values of -0.05±0.07 logMAR and -0.07±0.06 logMAR, respectively. 86.67% and 95.56% of the eyes had ≥20/20 UDVA and CDVA, respectively, with 100% achieving ≥20/25 for both UDVA and CDVA. At 80 cm, the mean monocular logMAR UIVA and DCIVA were 0.18±0.14 and 0.14±0.14, and at 66 cm the values were 0.20±0.15 and 0.19±0.15, respectively. At 80 cm 20% of the eyes had ≥20/25 DCIVA and 60% had ≥20/32 DCIVA. These values changed to 15.56% and 40% of the eyes at 66 cm. In terms of near vision, the mean monocular logMAR UNVA and DCNVA were 0.04±0.10 and 0.03±0.10, respectively. 53.33% of the eyes had ≥20/20 UNVA and DCNVA, with 86.67% achieving ≥20/25 UNVA and DCNVA.

Conclusion

The FineVision HP trifocal diffractive IOL provided accurate refractive outcomes with good visual acuity at different distances in Japanese eyes.

Visual and Refractive Outcomes of a New Hydrophobic Trifocal Toric Intraocular Lens

Purpose

To evaluate the visual outcomes and efficacy of astigmatism correction using a new hydrophobic trifocal toric intraocular lens (IOL).

Methods

This study involved 62 eyes implanted with the FineVision HP Toric IOL. The visual and refractive outcomes were assessed preoperatively and 6 weeks after the surgery. Specifically, monocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA) at 80 and 60 cm and uncorrected near visual acuity at (UNVA) at 40 cm were evaluated. The rotational stability of the lens was also assessed.

Results

Sixty-one eyes (98.39%) were within ±1.00D and 55 eyes (88.71%) were within ±0.50 D of spherical equivalent, with a mean value of 0.09±0.39 D. 51 (82.26%) and 61 (98.39%) eyes had a UDVA of ≥20/20 and ≥20/25, respectively, and for CDVA these values were as follows: 59 (95.16%) and 62 eyes (100%), respectively. The mean UDVA and CDVA were 0.01±0.06 and -0.01±0.04logMAR, respectively. Greater than or equal to unaided 20/20 vision was achieved at 40 cm in 42 (67.74%), UIVA at 60 cm in 42 (67.74%) and 50 eyes (80.65%) at 80 cm. Those achieving ≥20/25 were 56 (90.32%, 40 cm), 59 (95.16%, 60 cm), and 62 eyes (100%, 80 cm). Postoperative mean values were 0.04±0.07, 0.03±0.07, and 0.00±0.07logMAR for UCNVA, UIVA at 60 cm, and UIVA at 80 cm, respectively. The mean rotation of the IOL was 5.8 degrees.

Conclusion

This hydrophobic trifocal toric IOL provides good refractive outcomes with excellent visual acuity across multiple distances, providing a full range of focus.

Long-term Clinical Outcomes After Bilateral Implantation of Two Trifocal Diffractive IOLs

PURPOSE

To show clinical outcomes after bilateral implantation of either a hydrophobic FineVision POD F GF or a hydro-philic FineVision POD F intraocular lens (IOL) (Beaver-Visitec International, Inc).

METHODS

A total of 110 patients with cataract were randomized to receive either POD F GF or POD F IOLs and followed up for 2 years. The measurements included refraction, monocular and binocular uncorrected and corrected distance (UDVA and CDVA), intermediate (UIVA and DCIVA), and near (UNVA and DCNVA) visual acuities, defocus curve, photopic and mesopic contrast sensitivity, photic phenomena, and patient-reported outcomes.

RESULTS

The mean spherical equivalent was similar in both groups and stable across visits (< 0.25 diopters [D]). At 2 years, 81.8% and 90.5% of eyes were within ±0.50 D in the POD F GF and POD F IOL groups, respectively (100% for ±1.00 D in both groups). At 2 years, 100% and 90.5% of the patients presented a binocular CDVA of 20/25 or better; 93.9% and 85.7% of patients a DCIVA of 20/25 or better and 87.5% and 70% of patients a DCNVA of 20/25 or better, for the POD F GF and POD F IOL groups, respectively. The defocus curve showed continuous visual acuity, being 20/32 or better in both groups over a 4.50 D range. Both groups presented good contrast sensitivity for photopic and mesopic conditions, and the size and intensity of halo and glare phenomena were similar between the two. Both groups also included a high percentage of patients who reported that they had stopped wearing glasses and greater than 80% satisfaction and recommendation levels.

CONCLUSIONS

This study showed comparable long-term visual and refractive outcomes of both IOL models after cataract surgery. [J Refract Surg. 2023;39(12):798-807.].

Influence of isofocal intraocular lenses on objective refraction based on autorefraction and aberrometry

PURPOSE

To evaluate and compare the objective refractions obtained by autorefraction and aberrometry under different lighting conditions with an isofocal intraocular lens (Isopure, BVI medical, Liége, Belgium) compared to a monofocal control lens (Micropure, BVI medical, Liége, Belgium) with the same platform and material.

METHODS

Prospective, comparative and randomized study on patients undergoing cataract surgery and bilateral isofocal or monofocal IOL implantation. A total of 44 subjects were randomly assigned to either the isofocal group (n = 22) or the Micropure (n = 22). Manifest refraction (MR) was always performed under the same lighting conditions for all the patients. For objective refraction the autorefractor KR8800 and the aberrometer OPD-Scan III (Nidek Inc., Tokyo, Japan.) were used. For each eye included in the study, six result sets were collected: MR, AR (autorefraction measured with the autorefractor), WF-P and WF-M (Zernike-coefficients-based objective refraction, photopic and mesopic pupil size), OPD-C and OPD-M (autorefraction measured with the aberrometer in photopic and mesopic conditions).

RESULTS

The mean sphere for MR was 0.03 ± 0.32D for the Isopure group and 0.24 ± 0.22D for the monofocal group (p = 0.013). For the Isopure group, Friedman analysis showed statistically significant differences for sphere measured with WF-P (p = 0.035), WF-M (p = 0.018) and OPD-M (p = 0.000), and SE measured with OPD-M (p = 0.004). In the Micropure lens group, the Friedman analysis showed differences for all values studied (p < 0.05). Correlation coefficients showed that AR is the objective method with the strongest correlation values for all components of refraction for both groups.

CONCLUSION

The modification of the surfaces of the isofocal lens does not have a negative impact on the refraction obtained by AR compared to a standard monofocal intraocular lens.

Automated and subjective refraction with monofocal, multifocal, and EDOF intraocular lenses: review

Automated refraction (Scheiner principle) is universally used to start a visual examination. Although the results are reliable in eyes implanted with monofocal intraocular lenses (IOLs), they may be less precise with multifocal (mIOL) or extended depth-of-focus (EDOF) IOLs and can even indicate a refractive error that does not clinically exist. Autorefractor results with monofocal, multifocal, and EDOF IOLs were investigated through literature search analyzing the papers reporting the difference between automated and clinical refraction. The average difference ranged between -0.50 diopter (D) and -1.00 D with most mIOL and EDOF IOLs. The differences in astigmatism were generally much lower. Autorefractors using infrared light cannot measure eyes with high technology IOLs precisely because of the influence of the refractive or of the diffractive near add. The systematic error induced with some IOLs should be mentioned in the IOL label to prevent possible inappropriate refractive procedures to treat apparent myopia.

Long Term Clinical Outcomes of Hydrophilic and Hydrophobic Versions of a Trifocal IOL with the Same Optical Design

Purpose

To show the visual and refractive outcomes in Asian eyes with cataract when bilaterally implanted with either a hydrophobic FineVision POD F GF or a hydrophilic FineVision POD F intraocular lens (IOL).

Methods

Forty-six patients were randomized to receive POD F GF or POD F IOLs. Visual and refractive outcomes were assessed up to 24 months post-surgery. Measurements included uncorrected-distance visual acuity, corrected-distance visual acuity (CDVA), distance-corrected intermediate visual acuity (DCIVA), distance-corrected near visual acuity (DCNVA), refraction, defocus curve, photopic and mesopic contrast sensitivity, and patient-reported outcomes.

Results

Mean spherical equivalent was close to emmetropia for both groups and stable across postoperative visits. Overall, 97.73% and 100% of eyes in the POD F GF IOL group and 95.65% and 100%, of eyes in the POD F IOL group were within ±1.00D of the target refraction at 12 and 24 months, respectively. All patients showed a CDVA of ≥20/25 at 12- and 24-months post-surgery. In both groups, 24 months post-surgery 91% of patients presented a DCIVA of ≥20/25 and 83.3% of patients had a DCNVA of ≥20/25. Defocus curve showed continuous visual acuity, being 20/32 or better in both groups over a 4.00D range between 1.00D and -3.00/-3.50D. Both groups showed good contrast sensitivity values for photopic and mesopic conditions. Overall, 86.4%, 86.4%, and 72.7% of patients implanted with the POD F GF IOL reported not wearing glasses at all for distance, intermediate, and near vision, respectively. These values were 81.8%, 86.4%, and 90.9% for patients implanted with the POD F IOL. Both groups of patients reported similar satisfaction percentages (100% very satisfied/satisfied) and would recommend the procedure (100% definitively yes/probably yes).

Conclusion

This study demonstrates good visual and refractive outcomes for both the FineVision POD F GF and the FineVision POD F IOLs when implanted in Asian eyes.

Update on Biometry and Lens Calculation - A Review of the Basic Principles and New Developments

These days, accurate calculation of artificial lenses is an important aspect of patient management. In addition to the classic theoretical optical formulae there are a number of new approaches, most of which are available as online calculators. This review aims to explain the background of artificial lens calculation and provide an update on study results based on the latest calculation approaches. Today, optical biometry provides the computational basis for theoretical optical formulae, ray tracing, and also empirical approaches using artificial intelligence. Manufacturer information on IOL design and IOL power recorded as part of quality control could improve calculations, especially for higher IOL powers. With modern measurement data, there is further potential for improvement in the determination of the axial length to the retinal pigment epithelium and by adopting a sum-of-segment approach. With the available data, the cornea can be assumed to be a thick lens. The Kane formula, the EVO 2.0 formula, the Castrop formula, the PEARL-DGS, formula and the OKULIX calculation software provide consistently good results for artificial lens calculations. Excellent refractive results can be achieved using these tools, with approximately 80% having an absolute prediction error within 0.50 dpt, at least in highly selected study populations. The Barrett Universal II formula also produces excellent results in the normal and long axial length range. For eyes with short axial lengths, the use of Barrett Universal II should be reconsidered; in this case, one of the methods mentioned above is preferable. Second Eye Refinement can also be considered in this patient population, in conjunction with established classic third generation formulae.

Implementation of Kiosk-Type System Based on Gaze Tracking for Objective Visual Function Examination

To demonstrate that the near-point-of-convergence (npc) examination is performed subjectively, the visual fixation and four-prism diopter (Δ) base-out (BO) examinations can be conducted with a kiosk-type objective examination method based on gaze tracking, and can be compared with the existing method. Objective examination equipment was used to verify effectiveness. Fifteen adult men and women in their 20s and 30s (26.87 ± 3.31 years) with visual acuity of 0.8 (logMAR: 0.1, Snellen: 20/25(6/7.5)) or higher (corrected vision in the case of ametropia) underwent the npc, visual fixation, and 4 Δ BO examinations based on the existing examination method followed by the gaze-tracking-based kiosk-type examination method. Three examinations were performed, and a comparative analysis was conducted. The gaze tracking method used a method of extracting eye feature points, and it was judged that the ocular moved when the movement of 30 eye feature points at the edge of the iris was detected. In the comparison between the existing method and the kiosk-type method, there were no statistically significant differences in npc, visual fixation, and 4 Δ BO examinations. Npc examinations were performed extensively by the existing subjective method, however, it seems that these can be conducted objectively using the kiosk-type method. Visual fixation and 4 Δ BO examinations require high-examination proficiency because finely moving ocular movements need to be observed, but it is judged that examinations can be performed more easily and accurately when combined with the kiosk-type method. The symmetrical characteristics between the two test results are expected to serve as a basis for using the kiosk-type examination method in clinical practice.