Search Results (42)

Purpose: To examine concordance in biometry, keratometry, and intraocular lens (IOL) calculation between the Heidelberg Anterion Cataract App and the Zeiss IOLMaster 700 in a US population presenting for cataract evaluation. Methods: In this retrospective cross-sectional study, 64 eyes of 40 patients presenting for cataract evaluation underwent imaging with both devices. Agreement was assessed for axial length (AL), anterior chamber depth (ACD), lens thickness (LT), white-to-white distance (WTW), central corneal thickness (CCT), pupil diameter (PD), and anterior, posterior, and total keratometry using Lin’s concordance correlation coefficient (CCC), Bland–Altman analysis and generalized estimating equations. Non-toric and toric IOL calculations were performed with the Barrett Universal II and Barrett True-K Toric formulas, respectively. Results: Concordance was excellent for AL, ACD, LT, and CCT (CCC > 0.980), with no significant difference in AL. Compared with IOLMaster 700, Anterion measured larger PD (+0.56 mm), deeper ACD (+0.07 mm), thicker LT (+0.07 mm), thinner CCT (−3.19 μm), and smaller WTW (−0.22 mm; all p < 0.01). Anterior keratometry showed excellent concordance (CCC ≥ 0.980) despite small flatter offsets in average K, K1, K2 and difference in (Δ)K (−0.13, −0.08, −0.16 D, −0.10). Concordance was poor for posterior keratometry (average K: CCC = 0.529; Anterion steeper by 0.34 D), fairly good for total keratometry (average K: CCC = 0.891, Anterion flatter by 0.68 D), and these systematic inter-device offsets may be clinically relevant. For non-toric calculations, unrounded spherical IOL power agreed within 0.50 D in 88.88% (N = 56/63) of eyes and predicted residual refractive error within 0.25 D in 95.24% (N = 60/63). For toric calculations, predicted residual refractive error and residual astigmatism agreed within 0.25 D in 95.16% (N = 59/62) and 85.48% (N = 53/62) of eyes, respectively. Conclusions: Anterion and IOLMaster 700 showed strong agreement in core biometry, anterior keratometry, and predicted refractive outcomes, though posterior and total keratometry differed systematically. Postoperative refractive outcome studies are needed before the devices can be considered interchangeable in routine practice. Full article

Background: Acute angle-closure glaucoma (AACG) is an emergency requiring rapid intervention to prevent irreversible optic nerve damage and permanent vision loss. Methods: This narrative review synthesizes the systemic medication classes most implicated in medication-induced AACG, outlining their underlying pathophysiological mechanisms, typical timing of onset, and practical risk-reduction strategies. Evidence was collected through targeted searches of the PubMed, Google Scholar, Cochrane Library, and Web of Science databases, focusing on major review articles, pharmacoepidemiologic studies, and clinical consensus guidelines. Source selection and data synthesis followed a narrative approach without formal risk of bias assessment or meta-analysis. Results: The literature consistently implicates sulfonamide derivatives (mainly topiramate), serotonergic antidepressants and triptans, potent systemic anticholinergics, and adrenergic decongestants. Sulfonamides typically precipitate bilateral, non-pupillary-block AACG via ciliochoroidal effusion, secondary anterior displacement of the lens-iris diaphragm, and an acute myopic shift. Conversely, serotonergic, anticholinergic, and adrenergic agents typically trigger classic pupillary-block AACG in anatomically predisposed eyes with pre-existing narrow angles. Adverse events predominantly occur shortly after treatment initiation or dose escalation. Management relies on prompt medication discontinuation and rapid intraocular pressure reduction. Importantly, cycloplegics are preferred over miotics in effusion-induced cases. Given the rarity of these events, brief patient education represents a pragmatic and scalable approach, although its direct clinical effectiveness in reducing event rates has not yet been formally established. Conclusions: A select group of widely prescribed systemic medications are associated with most cases of medication-induced AACG. Improving clinician awareness, providing brief patient counseling on warning symptoms, and ensuring prompt ophthalmic evaluation represent the most practical currently available risk-reduction strategies to prevent vision loss. Full article

Background/Objectives: To assess the refractive and visual outcomes after implantation of an isofocal optic-design intraocular lens (IOL) with double C-loop haptics following cataract surgery in eyes with primary open-angle glaucoma (POAG). Methods: This was a prospective, open-label, interventional exploratory study that considered POAG eyes undergoing cataract surgery with implantation of the Isopure Serenity (Beaver-Visitec International, Inc. [BVI], Waltham, MA, USA) IOL. Primary outcomes measured included manifest 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, and photopic binocular defocus curve were evaluated 3 months after surgery. Results: In total, 22 eyes of 11 patients (nine women, mean age of 68.3 ± 8.3 years) with POAG were enrolled and completed the clinical study. The study found that 100% of the eyes were within ±0.50 D and 86.36% of the eyes showed a postoperative refractive cylinder ≤ 0.25 D. The mean spherical equivalent and refractive cylinder were −0.06 ± 0.30 D and −0.13 ± 0.33 D, respectively. It was also shown that 86.36% and 100% of the eyes had 20/20 or better UDVA and CDVA, respectively. Furthermore, 95.45% and 77.27% of eyes presented a monocular DCIVA value of ≥20/32 at 80 and 66 cm, respectively, and 68.18% of eyes presented a monocular DCNVA value of ≥20/40. The mean monocular CDVA, DCIVA at 80 cm, DCIVA at 66 cm, and DCNVA were −0.09 ± 0.04, 0.12 ± 0.07, 0.21 ± 0.07 and 0.32 ± 0.07 logMAR, respectively. The binocular defocus curve showed good visual acuity at distance and intermediate vision. Conclusions: The isofocal Isopure Serenity IOL can be implanted in eyes with POAG after cataract surgery, achieving a satisfactory visual performance. Our results suggest that this IOL model is a viable option for selected patients with controlled early/moderate POAG and without central visual field involvement diagnosed with cataracts. Full article

Glaucoma surgery is entering a precision-based era in which surgical success is determined not only by intraocular pressure reduction, but also by the anatomical mechanism targeted, the expected durability of effect, safety profile, medication burden, quality of life, and preservation of future therapeutic options. Microinvasive glaucoma surgery (MIGS) has become an important component of this paradigm by expanding the surgical continuum toward earlier, anatomically targeted, and tissue-sparing intervention. However, MIGS does not represent a homogeneous procedural category; rather, it encompasses distinct approaches that modulate different components of aqueous humor dynamics, including the trabecular meshwork, Schlemm’s canal, distal collector channels, the subconjunctival space, the suprachoroidal pathway, and aqueous production. This narrative review synthesizes contemporary evidence and proposes a mechanism-based framework for glaucoma surgery, with particular emphasis on trabecular and Schlemm’s canal-based procedures as representative examples of physiologically oriented conventional outflow enhancement. Canal-based interventions, trabecular bypass, goniotomy, trabeculotomy, and canaloplasty are most appropriate when enhancement of conventional outflow can achieve clinically meaningful pressure and medication reduction, particularly in mild-to-moderate open-angle glaucoma. By contrast, subconjunctival filtration, trabeculectomy, and aqueous shunt surgery remain indispensable when lower target pressures are required, especially in advanced or rapidly progressive disease. Lens extraction and ciliary body-directed procedures further illustrate the importance of aligning surgical strategy with disease phenotype and anatomical mechanism. The future of glaucoma surgery will therefore depend on individualized procedure selection guided by glaucoma stage, target pressure, angle and lens anatomy, outflow pathway integrity, safety considerations, and long-term surgical sequencing. Full article

Background/Objectives: We aim to determine whether prior cataract surgery affects the intraocular pressure (IOP)-lowering effect of selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG). Methods: This prospective interventional cohort study initially included 92 patients with POAG who were inadequately controlled or intolerant to topical therapy and were treated with SLT. Of these, 84 patients completed all scheduled visits and constituted the final analyzed dataset. Patients were divided into phakic and pseudophakic groups, with cataract surgery performed at least one year before SLT in all pseudophakic eyes. All patients underwent standardized 360-degree SLT by a single specialist. The primary outcome was IOP reduction at one year. Secondary outcomes included percentage IOP reduction and treatment success, defined as ≥20% IOP reduction. Data were analyzed using Statistica^TM 14.0.1.25 (TIBCO Software Inc., Palo Alto, CA, USA, USA). Results: Before SLT, the median IOP was 20.5 mmHg in phakic eyes and 21 mmHg in pseudophakic eyes. One year after SLT, median IOP decreased insignificantly in phakic eyes (4.0 mmHg; p = 0.262), whereas it decreased significantly in pseudophakic eyes (5.5 mmHg; p = 0.004). At one year post-SLT, an IOP reduction of ≥20% was observed in 53.6% of phakic and 72.7% of pseudophakic eyes. Pseudophakic patients were significantly older than phakic patients, as expected, because age-related senile cataract is more common in older individuals, and the groups also differed by gender distribution. This gender imbalance was coincidental and reflected the non-randomized inclusion of POAG patients according to clinical need for SLT rather than predefined matching. In unadjusted analyses, one-year IOP reduction was positively associated with age (p = 0.048), pretreatment IOP (p < 0.001), and prior cataract surgery (p = 0.047). However, after adjusting for age, gender, and baseline IOP in a multivariate sensitivity analysis, prior cataract surgery was not an independent predictor of success; only pretreatment IOP predicted a significant reduction (p = 0.031) in the analysis of 84 eyes. Conclusion: Although pseudophakic eyes showed greater unadjusted IOP reduction after SLT over one year, lens status was not an independent predictor after adjustment for potential confounders. Therefore, the observed pseudophakic advantage should be interpreted as a hypothesis-generating association warranting further research into the effect of pseudophakia on SLT response. Full article

Background/Objectives: Choosing the most appropriate intraocular lens (IOL) for presbyopia management may be challenging given the expanding selection of available designs. This review provides an updated overview of current monofocal plus, extended depth of focus (EDoF), and trifocal IOLs, summarizing their optical properties and laboratory and clinical findings, including visual acuity outcomes and side effects. Methods: A literature search was conducted using PubMed to identify studies on monofocal plus, EDoF, and trifocal IOLs, with emphasis on optical characteristics, visual acuity outcomes, and reported photic phenomena. Results: Monofocal plus IOLs demonstrate an improvement in depth of field compared to monofocal lenses, as evidenced by significant broadening of the defocus curve. Both refractive and diffractive EDoF IOLs show improved intermediate visual acuity, with diffractive models offering greater depth of field but a higher risk of dysphotopsia. Trifocal IOLs offer the best visual acuity at all three foci: near, intermediate, and distance. Patients’ needs may be customized using sulcus- or capsulotomy-fixated IOLs, mix-and-match strategies, and binocular IOL systems. Conclusions: Based on this literature review, clinical and optical bench studies to date support optimized IOL selection based on individual patient needs for presbyopia management. However, consideration of understudied or newly released IOL models is limited as future research is needed. Additionally, further prospective, randomized, controlled, and masked studies with large sample sizes on all IOL models may further support patient decision-making by contributing to a more comprehensive literature. Full article

Background/Objectives: To assess the accuracy of several intraocular lens power calculation formulas in phacotrabeculectomy for open angle glaucoma. Methods: Patients who underwent phacotrabeculectomy for open angle glaucoma were included. Refraction and biometry measurements were repeated at 3, 6 and ≥12 months. Prediction error (PE) and absolute error (AE) were calculated using the SRK/T, Holladay 1, Hoffer Q, Haigis, Kane, Emmetropia Verifying Optical (EVO) and Barrett Universal II formulas at ≥12 months, and their accuracy was compared using linear mixed-effects models accounting for repeated measurements within the same eye and inter-eye correlation. Results: Sixty eyes from 40 patients were included. The linear mixed-effects model showed a significant overall effect of formula on PE (χ²(6) = 119.14, p < 0.001). Most formulas showed a tendency toward a hyperopic refractive shift, whereas Haigis showed a negative PE. Based on estimated marginal mean AE, the formulas were ranked as follows: EVO (0.548 D), Barrett Universal II (0.551 D), Holladay and SRK/T (0.561 D), Haigis (0.572 D), Kane (0.577 D) and Hoffer Q (0.617 D). However, the AE did not significantly differ among the formulas (χ²(6) = 3.75, p = 0.711). The percentage of eyes within ± 1.00D of PE ranged from 81.7% to 90% across the formulas (p > 0.05). Significant axial length shortening, anterior chamber deepening and mean keratometry reduction were detected postoperatively at ≥12 months (p < 0.05). Conclusions: Despite postoperative ocular anatomic changes, all formulas showed acceptable refractive accuracy after phacotrabeculectomy. Although no significant difference in the AE was detected among the formulas, the PE differed significantly, with most formulas showing a tendency toward a hyperopic shift and Haigis showing a myopic shift. This inter-formula difference should be considered when selecting the refractive target, particularly when using formulas that tend toward hyperopic PE. Full article

The ultra-precision machining of micro-optics from low glass transition temperature (T_g) hydrophobic polymers is frequently compromised by thermal instability and kinematic constraints imposed by on-axis turning. To address these challenges, this study presents a novel clamping–cooling system engineered for the off-axis diamond turning of low-T_g polymers. The design integrates vacuum clamping for workpiece stabilization with an embedded microchannel network for efficient thermal management. Strategic material selection effectively balances thermal insulation with mechanical stability. Performance evaluations demonstrated robust thermal regulation: lens blank surface temperatures stabilized at 6 °C during stationary testing, and the system was able to drop below 0 °C under maximum cooling targets. This strict thermal control enabled achieving nanometer surface roughness. Ultimately, this modular system facilitates the scalable, simultaneous production of high-quality, polishing-free intraocular lenses (IOLs), advancing manufacturing capabilities for complex precision optics. Full article

Background/Objectives: Premium intraocular lenses (IOLs) are increasingly being selected for cataract and refractive lens surgery, but their functional performance depends critically on pupil size and corneal spherical aberration (SA). This study evaluates how these factors modulate the optical behavior of the RayOne EMV and Tecnis Synergy using a profilometry-based Through Object modulation transfer function (TO MTF) analysis. Methods: The surface profiles of the RayOne EMV and Tecnis Synergy were measured with a confocal optical profilometer and implemented in pseudophakic eye models via ray tracing. TO MTF at 50 cycles/mm was computed for object vergences from −4.0 D to +2.0 D over entrance pupil diameters from 2.0 to 5.5 mm in three corneal configurations derived from the Liou–Brennan model and ISO recommendations: mean population SA, aberration-free, and a myopic LASIK-like oblate cornea. Simulated optotype images were generated to relate TO MTF values to the expected distant, intermediate, and near visual performances. Results: RayOne EMV delivered high-quality distant image performance in all models. Its depth of focus increased only modestly and showed a strong dependence on pupil size. Intermediate and near vision rarely reached clinically acceptable levels. The Tecnis Synergy produced a broad depth-of-field plateau in distant to near visual performance for mean population spherical aberration at a 3.5 mm pupil. However, image quality at 90 cm remained limited. Optical performance worsened with increasing pupil size and positive spherical aberration, particularly under post-myopic LASIK conditions. Conclusions: The RayOne EMV behaves predominantly as a distance-oriented design with minimal true presbyopic benefit; the Tecnis Synergy provides a wider range of vision but is highly sensitive to corneal spherical aberration and pupil size, so thorough preoperative evaluation of corneal asphericity and functional pupil diameter is essential for IOL selection and power targeting. Full article

Background and Objectives: Tear film instability and corneal surface irregularity are important sources of variability in keratometric and corneal topographic measurements, particularly affecting astigmatic magnitude and axis. Accurate preoperative biometry is crucial for optimal refractive outcomes in cataract surgery. Dry eye disease (DED) may compromise the reproducibility of keratometric parameters, leading to errors in intraocular lens (IOL) power calculation. This study aimed to evaluate the impact of DED on the reproducibility of keratometric measurements and to assess the effect of a four-week treatment with lipid-containing artificial tears on these parameters in cataract patients. Materials and Methods: This cross-sectional study included 116 patients scheduled for cataract surgery, of whom 65 (56.0%) had DED and 51 (44.0%) served as controls. All patients underwent two preoperative keratometric measurements 10–20 min apart (IOL1 and IOL2). The control group proceeded to surgery the next day, while surgery in the DED group was postponed. Patients with DED received preoperative therapy with lipid-containing artificial tears. Follow-up assessments occurred one month after therapy (keratometric measurement named IOL3) and eight weeks postoperatively. Clinical evaluation included slit-lamp examination, dry eye testing according to Dry eye Workshop II (DEWS II) criteria: Ocular surface Disease Index (OSDI), Tear Break-Up Time (TBUT), Schirmer I, Oxford staining, and meibomian gland assessment), ocular biometry, and postoperative spherical equivalent measurement using an auto ref-keratometer. Nonparametric statistical analyses were applied to evaluate associations between parameters. Results: In the DED group, corneal astigmatism showed a significant difference between IOL1 and IOL2 (Wilcoxon signed-rank test {Z = 2.43; p = 0.015}). Significant changes in predicted IOL power were observed between pretreatment and posttreatment values (t = 2.57; p = 0.013) and between IOL2 and IOL3 (t = 2.23; p = 0.029), indicating improved keratometric stability following tear film therapy. No additional significant correlations were identified. Conclusions: DED adversely affects the reproducibility of keratometric measurements and may compromise IOL power selection. Preoperative identification and treatment of DED, followed by repeated biometry after tear film stabilization, are strongly recommended to enhance refractive accuracy and optimize surgical outcomes in cataract patients. Full article

As surgeries using multifocal intraocular lenses (IOLs) to correct both cataracts and presbyopia have become common, it has become essential for clinicians to understand their basic optical characteristics to select the optimal lens for their patients. However, there are relatively few review articles on optics that are directly useful to clinicians who perform surgery on patients. In this paper, we systematically review fundamental concepts, from the basic properties of light, geometric optics, and Gaussian approximation to lens performance metrics like the point spread function and modulation transfer function (MTF), and the clinical implications of spherical and chromatic aberrations. Based on these principles, the mechanisms of major multifocal technologies are explained. We also explore the refractive extended depth of focus lenses, which expand the range of focus by precisely controlling higher-order spherical aberrations. In contrast, diffractive lenses use diffractive kinoforms to split light into multiple foci, and they may also leverage higher diffraction orders to correct chromatic aberration. However, this multifocality involves an optical compromise, often resulting in a reduced overall MTF compared to monofocal IOLs and photic phenomena such as glare and halo. In conclusion, while multifocal IOLs are groundbreaking technology that significantly enhances quality of life by reducing spectacle dependence, this comes at the cost of sacrificing optimal image quality. Therefore, a thorough understanding of these optical principles by ophthalmologists is crucial for selecting the optimal lens according to each patient’s ocular condition and for managing postoperative outcomes. Full article

Background: Trifocal and extended depth-of-focus (EDoF) multifocal intraocular lenses (MIOLs) are currently widely used after cataract surgery to restore vision at multiple distances. In vitro studies of MIOLs are necessary to evaluate their optical behavior providing surgeons with evidence to support the appropriate selection of the best lens for each patient. Methods: The FineVision POD F, Acriva Trinova Pro C, AT LARA 829MP, and AcrySof IQ Vivity lenses were assessed using a dedicated optical bench. Optical quality was quantified using the through-focus modulation transfer function (TF-MTF) and the area under the modulation transfer function (MTFa), both calculated from the point spread function (PSF). Halo formation was qualitatively analyzed. Results: The FineVision POD F and Acriva Trinova Pro C lenses exhibited trifocal behavior, with optical performance varying according to pupil size and wavelength. The AT LARA 829MP lens functioned as a low-addition bifocal under monochromatic green light but demonstrated EDoF characteristics under polychromatic illumination. The AcrySof IQ Vivity lens displayed an EDoF profile derived from the superposition of multiple closely spaced foci under polychromatic evaluation. Halo assessment revealed lens-dependent differences, with the AcrySof IQ Vivity showing the smallest halo extent. Conclusions: This in vitro study demonstrates differences in the optical and chromatic performance of trifocal and EDoF IOLa. Trifocal designs showed variable behavior related to diffraction orders the use but generally favored far vision under mesopic conditions, with similar trends observed in EDoF lenses. EDoF designs produced fewer halos than trifocals. These quantitative findings may translate into clinically relevant effects, supporting MIOL selection tailored to patient needs and improving the predictability and personalization of surgical outcomes toward greater spectacle independence. Full article

Anterior segment optical coherence tomography (AS-OCT) has emerged as a crucial imaging technique in ophthalmology, particularly for evaluating intraocular structures and the behavior of phakic and secondary intraocular lenses (IOLs). This narrative review summarizes the latest findings and clinical applications of OCT regarding phakic and secondary IOLs, focusing on their effectiveness, safety, and factors influencing performance. Through a comprehensive analysis of current literature, we explore how OCT facilitates the assessment of IOLs on key anatomical parameters—such as vault, angle configuration, lens centration, tilt, and haptic positioning—essential for optimizing surgical outcomes and minimizing postoperative complications. In phakic IOLs, including posterior chamber lenses such as the Implantable Collamer Lens (ICL, STAAR Surgical, Monrovia, CA, USA) and iris-fixated lenses, such as Artiflex (Ophtec BV, Groningen, The Netherlands), OCT enables precise evaluation of the anterior segment, aiding both candidate selection and long-term monitoring. In secondary implants for aphakia—especially iris-fixated lenses like Artisan (Ophtec BV, Groningen, The Netherlands) and sutureless scleral-fixated lenses such as the Carlevale IOL (Soleko, Rome, Italy)—or those implanted via the Yamane technique, OCT provides high-resolution visualization of haptic fixation, IOL stability, and potential complications, including tilt or decentration. This review also highlights comparative insights between fixation techniques, underscores the need for standardized OCT protocols, and discusses the integration of artificial intelligence tools. In summary, the routine use of OCT in the preoperative and postoperative management of phakic and secondary IOLs has been increasingly incorporated into clinical practice, as it enhances clinical decision-making and improves patient outcomes. Full article

Background/Objectives: Cataract surgery often reveals preexisting corneal astigmatism, which can be corrected using a toric intraocular lens (T-IOL). However, postoperative T-IOL rotation may compromise correction. We investigated T-IOL rotation, focusing on deployment time and proximity to the posterior capsule (PC), using intraoperative optical coherence tomography (iOCT). Methods: Six different T-IOL models were inserted into acrylic simulated lens capsule models under different tacking durations (5 s, 30 s, and 60 s) and temperature conditions (23 °C, 28 °C, and 32 °C). The selection criteria for porcine lenses for examination required that they match human lens dimensions, typical of those used to train cataract surgeons. T-IOL misalignment due to vibration was assessed. Additionally, the impact of temporary intraocular pressure (IOP) reduction on T-IOL proximity to the PC was measured using iOCT in porcine eyes. Results: Tacking time and temperature independently affected T-IOL deployment, with shorter tacking durations and higher temperatures leading to faster deployment. Among lenses tested under identical tacking time and temperature conditions, iSert Micro Toric Aspheric 1-Piece IOL (355T3) had the slowest expansion time, while Avansee™ Preload 1-Piece Toric (YP-T3) had the fastest. Porcine eyes with a corneal white-to-white major axis < 16.0 mm fell within the 95% confidence interval for matching human lens size. Temporarily reducing IOP during surgery improved T-IOL adhesion to the PC, reducing both the occurrence and degree (from 14.0° to nearly 0°) of postoperative rotation. Conclusions: Optimal T-IOL deployment, temporary IOP reduction during surgery, and enhanced adhesion to the PC can reduce the risk and degree of T-IOL rotation. Intraoperative iOCT aids in monitoring T-IOL positioning, which is essential to prevent rotation. Accumulated fluid between the T-IOL and PC may contribute to rotation, which requires further investigation. These findings provide practical strategies for enhancing T-IOL stability and improving the effectiveness of astigmatism correction in cataract surgery. Full article

Purpose: The accurate intraocular lens (IOL) power calculation is essential in phacoemulsification. The latest IOL power calculation formulas, and their new classification and method to assess their accuracy, were described and analyzed. Design: Narrative review. Methods: The manuscript includes articles on IOL power calculation published between 2019 and 2025. The following key words, such as “phacoemulsification”, “IOL power calculation formula”, “AI-based formulas”, “IOL power selection”, “IOL formulas classification”, IOL prediction” were used to identify papers by searching medical databases (Pubmed/MEDLINE, Google Scholar, Crossref). PRISMA methodology was used to select articles. Finally, 33 peer-reviewed English-language studies with a sample size of at least 120 eyes were included in the analysis. Results: Ten IOL power calculation formulas that have been introduced and published over the past 5 years were included in the study. Five of them are artificial intelligence based (Karmona, Hoffer QST, Nallasamy, Zhu-Lu and Zeiss-AI), four are vergence (Emmetropia Verifying Optical, Naeser 2, Voytsekhivskyy Regression Function-Gender and Castrop), and one is ray-tracing (the O formula). In this review, the formulas are introduced and analyzed, with a discussion of selected studies assessing the accuracy of these IOL power calculation methods. Conclusions: New IOL power calculation formulas are constantly being developed. They are mostly based on artificial intelligence. New methods are still being sought to assess the accuracy of formulas, and root mean square absolute error is one of them Full article