The Eye Show • EyeDoc2020
What Is the Best Cataract Surgery and Intraocular Lens for You?
It remains the best time in the history of the world to have cataract surgery. Our complication rates are incredibly low. In my hands, the femtosecond laser has helped lower my complication risk even further, close to zero in routine cases, though no eye surgery is ever completely without risk.
What the femtosecond laser is, and who it is for
The femtosecond laser is a computer-guided laser that performs several of the most delicate steps of cataract surgery with a precision the human hand cannot match. It maps your eye and then makes its cuts in a fraction of a second, which is where the name comes from.
Think of the cataract as a cloudy pillow sitting inside a pillowcase. The laser opens the front of the pillowcase in a clean, perfectly round window and divides the cloudy pillow into small pieces. We then vacuum those pieces out with an ultrasound handpiece called phacoemulsification. Because the laser does so much of the fine work up front, many patients wake up the day after surgery with a beautifully clear cornea, and are usually very happy compared with standard surgery.
Who is, and is not, a candidate for the femtosecond laser
| Good candidate | Not ideal, or proceed with caution |
|---|---|
| Routine cataract surgery | Cannot lie flat or hold still |
| Astigmatism that benefits from precise laser incisions | Very small or poorly dilating pupil |
| Choosing a premium or adjustable lens where centration matters | Cornea scarred or cloudy enough to block the laser beam |
| Able to fixate for a short time; pupil dilates well | Certain very dense or advanced cataracts |
| Prior eye surgery, deep-set eyes, or narrow lids that prevent docking |
When the laser is not the right fit, standard manual cataract surgery is often the safer choice.
Why the implant is the hardest decision
Everyone who has a cataract removed needs an implant, called an intraocular lens, or IOL. Everyone should have one. Without it, you would need Coke-bottle-thick glasses to bend the light coming through your pupil onto your macula. There is no perfect implant, but the technology has improved dramatically since I was a resident, and choosing well is where most of the thinking happens.
The risks, in plain numbers
Every surgery carries risk. Incidence means how often something new happens in a group of people over a period of time. A 2 percent incidence means about 2 people in 100, or 20 in 1,000. The serious risks are rare. The most common issue today is needing a YAG laser capsulotomy to clear the back of the pillowcase, and the second is simply the need for glasses. I wear glasses myself and cannot wait to have my own cataract surgery one day.
| Risk | General incidence | What changes it for a long, myopic, glaucomatous eye |
|---|---|---|
| YAG capsulotomy | ~30% over time | Similar; unrelated to lens power[1] |
| Pressure (IOP) spike after surgery | ~10% ordinary eyes; ~28% in high myopia | Glaucoma raises it further; ~5% of glaucoma eyes spike above 30 mmHg[2][3] |
| Retinal detachment | ~0.4–2.9% over 10 years generally | ~9.5% over ~5 years in men under 60 with eye length ≥25 mm; up to 25× a non-myopic older eye[4][5][6] |
| Retinal detachment, per millimeter | — | Risk rises ~42% for every extra millimeter of eye length (hazard ratio 1.42/mm)[4] |
| Refractive surprise (power off target) | Small in normal eyes | Only ~61% of very long eyes land within 1.0 D; a hyperopic shift is common[7] |
| Capsular contraction / lens dislocation | Low | ~2.1% contraction, ~0.58% dislocation in high myopia[8] |
| Toric lens rotation losing astigmatism correction | — | Each 1° of rotation loses ~3.3% of the correction (see toric chart below)[9] |
The risk hierarchy for retinal detachment after cataract surgery is: intraoperative complications, then increasing eye length, then younger age, then male sex.[6]
So which lens should you choose? Start with two questions
Would I be OK needing progressive glasses?
Would I be OK needing readers?
If the answer to both is yes, then the lens your insurance covers, the monofocal, is the best option, and currently it is the only one insurance pays for.
If the answer is no (and for me it is no), ask two more questions.
Do I drive at night?
Would I mind halos and glare around lights, especially at night?
If yes (and for me it is yes on both), avoid multifocal implants such as PanOptix Pro, Symfony, and Synergy, and focus on the Light Adjustable Lens.
What your surgeon is asking while examining you
How much astigmatism is in each eye, and why toric rotation matters
Most astigmatism under 1.0 D can be softened with the corneal incision, but even 0.50 D can blur vision enough to send you back into glasses. Toric lenses correct astigmatism only while they stay in the exact orientation we set. If a toric rotates, the correction fades fast, which is a central reason I lean toward the Light Adjustable Lens for significant astigmatism.
| Toric lens rotation | Effect on the astigmatism correction |
|---|---|
| Each 1° | Loses about 3.3% of the correction[9] |
| Under 10° | Refraction changes less than 0.50 D, usually still acceptable[9] |
| 10° | About a third of the correction is gone; vision is meaningfully affected[9] |
| 30° | The astigmatism correction is completely nullified[9] |
| 45° | Essentially no correction remaining[9] |
| Modern toric stability | Average rotation is only ~2.36° across 4,863 eyes (2.27° at 1 year, 2.82° at 2 years); ~0.77% ever need repositioning[9] |
Modern torics are stable on average, but a single lens can still rotate, and the Light Adjustable Lens sidesteps the issue by correcting astigmatism with light after healing, with nothing to rotate.[9]
What is the axial length of each eye?
Axial length is the front-to-back length of the eye in millimeters. It decides which lens powers are available and how much retinal risk you carry.
| Axial length | Meaning |
|---|---|
| ~23–24 mm | Average eye |
| ≥26 mm | High myopia; higher retinal and refractive risk |
| ≥28 mm | Threshold of pathologic myopia; retina evaluation often wise before surgery |
Lens types, explained simply
| Lens type | What it does | Halos / glare | Glaucoma friendliness |
|---|---|---|---|
| Monofocal | One focus point, like a camera set to one distance | None | Best |
| Enhanced monofocal (refractive) | Smoothly bends light with a small intermediate boost | Minimal | Favorable |
| Light Adjustable Lens (refractive) | Monofocal you can fine-tune with light after surgery | None | Favorable |
| Multifocal (diffractive) | Splits light into 2–3 focus points with tiny rings | Highest | Avoid in moderate/advanced |
Refractive versus diffractive: explained simply
Imagine light entering your eye as a stream of tiny balls that must land on one spot at the back to make a sharp picture. A refractive lens bends the whole stream smoothly to that spot, like a plain magnifying glass. A diffractive lens has many tiny stair-step rings that split the stream into two or three smaller streams at once, sending some light near and some far. That split is how it gives distance and near without glasses, but each spot gets less light, and the leftover scattered light makes halos and glare around lights, worst at night.
Why this matters in glaucoma
In moderate to advanced glaucoma, the optic nerve is already damaged and already losing sensitivity to contrast and light. A diffractive lens further reduces and scatters the light reaching the retina, which worsens vision for these patients and can even interfere with the visual field tests we rely on to monitor glaucoma. That is why I avoid diffractive multifocal lenses in moderate and advanced glaucoma.
A real-world example
Consider a patient born in 1966 with a lifelong history of myopia and moderate glaucoma. She drives at night and wants good distance, intermediate, and near vision, and is comfortable using glasses for some tasks. She is interested in the LAL+, the PureSee, and the Eyhance Toric II.
| Measurement | Right eye (OD) | Left eye (OS) |
|---|---|---|
| Axial length | 27.42 mm (high myopia) | 28.04 mm (threshold of pathologic myopia) |
| Corneal astigmatism | 1.70 D @ 81° | 1.05 D @ 105° |
| Optic nerve | Moderate glaucoma, thinned nerve fiber layer, reduced contrast sensitivity | |
The biometry, and why the LAL+ power works here
Because these eyes are so long, the exact emmetropic power is low, and the lowest LAL+ power available (+10.0 D) sits slightly above it. That leaves each eye a little nearsighted, most of all the left. With the LAL+ this is a feature rather than a problem: after healing we use light to pull the refraction to target and to correct the astigmatism, with nothing to rotate.
| Parameter | OD (AL 27.42 mm) | OS (AL 28.04 mm) |
|---|---|---|
| Emmetropic IOL power (from biometry) | ~ +9.4 D | ~ +7.8 D |
| LAL+ power implanted | +10.0 D | +10.0 D |
| Power above emmetropia | +0.6 D | +2.2 D |
| IOL-to-refraction ratio at this length | ~1.3–1.4 : 1 | ~1.3–1.4 : 1 |
| Expected refraction before adjustment | −0.40 to −0.45 D | −1.50 to −1.70 D adjustable |
Powers estimated from the biometry printout (ZCT 119.3 column). The LAL uses a slightly different A-constant, so the exact emmetropic LAL power differs a little, but these values are a reasonable approximation.[7][10]
The three lenses, compared (recreated from the evidence)
Chart 1. LAL+ versus Eyhance Toric II (head to head)
| Feature | LAL+ | Eyhance Toric II | Evidence basis |
|---|---|---|---|
| Optical mechanism | Increased central power (refractive) | Continuous aspheric power change (refractive) | Cataract & Refractive lit. |
| Depth-of-focus extension | Broader than standard LAL; comparable to or slightly greater than Eyhance | Modest (~0.50 D beyond a standard monofocal); less than Vivity | Cataract & Refractive lit. |
| Adjustable after surgery? | Yes UV light adjusts sphere and cylinder | No | Cataract & Refractive lit. |
| Contrast sensitivity data | Measured at 100% and 25% contrast in a registry; no independent testing | Equivalent to a standard monofocal in multiple studies; confirmed safe in glaucoma | Cataract & Refractive lit. |
| Glaucoma-specific evidence | None | Three independent studies confirming safety across glaucoma severity | Clinical Medicine |
| Halos and glare | Not specifically reported in LAL+ studies | Comparable to a standard monofocal | Clinical Medicine |
| UV eyewear compliance | Required for about 2–3 weeks until lock-in | Not required | Current Opinion |
| Independence of key data | All studies RxSight-sponsored | Mix of industry and independent academic work | See sponsorship review |
Chart 2. Light Adjustable Lens versus PureSee (EDOF)
| Feature | LAL | PureSee (EDOF) | Evidence basis |
|---|---|---|---|
| Contrast sensitivity impact | None (monofocal) | Minimal (refractive EDOF) | Ophthalmology |
| Visual field interference | None | Minimal (non-diffractive) | Cataract & Refractive lit. |
| Refractive adjustability | Yes (±2.0 D post-op) | No | Cataract & Refractive lit. |
| Spectacle independence | Limited (monofocal or monovision) | Better intermediate range | American Journal of Ophthalmology |
| UV eyewear compliance | Required until lock-in | Not required | Current Opinion |
| Suitability for glaucoma | Favorable (monofocal optics) | Caution advised | Ophthalmology |
Chart 3. If we considered monovision (one eye set slightly near)
| Strategy | Estimated tolerance | Key concern for this patient |
|---|---|---|
| Mini-monovision (−0.75 to −1.25 D) | ~90–95% general population; unknown but likely lower with glaucoma | Reduced blur suppression from optic nerve disease; preserves stereo vision better than full monovision[11] |
| Conventional monovision (≥−1.75 D) | ~59–90% general population; likely much lower with glaucoma | AAO lists optic nerve disease as a relative contraindication; up to 6.7% reoperation even in healthy eyes; worse stereo vision[7] |
Only about 63% of myopic eyes longer than 26 mm reach 20/40 or better after cataract surgery because of coexisting eye conditions, which further limits any monovision benefit here.[7]
Chart 4. Lowest available powers and toric availability
| Lens | Lowest power | Toric version? | Fit for this patient (~7.8–9.4 D) |
|---|---|---|---|
| Eyhance Toric II | +5.0 D | Yes | Within range |
| Light Adjustable Lens / LAL+ | +10.0 D | Yes (adjustable) | Used at +10.0 D floor; small myopic residual corrected with light |
| PureSee | +5.0 D | No | No toric; 1.70 D OD left uncorrected |
Chart 5. Practical recommendation, matched to what you value most
| If you prioritize… | Best IOL choice | Rationale |
|---|---|---|
| Refractive accuracy plus intermediate vision, and you will follow the UV protocol | LAL+ | Combines adjustability (critical at ~28 mm) with a broadened depth of focus; avoids monovision. Trade-off: no glaucoma-specific safety data yet |
| Proven glaucoma safety plus intermediate vision, with a simpler workflow | Eyhance | Three independent studies confirm safety across glaucoma severity, no UV compliance needed. Trade-off: no post-op adjustability |
| Refractive accuracy above all else, standard optics acceptable | Standard LAL | Maximum adjustability with true monofocal optics and no depth-of-focus contrast concerns. Trade-off: no enhanced intermediate vision |
| The most conservative approach | Standard monofocal (e.g., ZCB00) | Longest track record, no depth-of-focus concerns. Trade-off: no intermediate benefit |
My recommendation for this patient
First choice: the Light Adjustable Lens Plus (LAL+)
Her two best options are the LAL+ and the Eyhance Toric II, and I am recommending the LAL+. Two features of her eyes drive this. First, her high myopia makes the final refraction hard to predict, and the LAL+ lets us correct it with light after the eye settles. Second, she has real astigmatism (1.70 D OD), and a toric lens loses roughly 3.3% of its correction for every degree it rotates. The LAL+ corrects astigmatism after healing with nothing to rotate, so the correction cannot slip out of place. The mild myopic residual left by the +10.0 D power floor is easily dialed to target during the same light adjustments.
Why not PureSee for this patient
| Concern | Why it matters here |
|---|---|
| No toric version | 1.70 D OD would be left largely uncorrected, blurring distance and intermediate |
| EDOF optics in moderate-to-severe glaucoma | Any contrast loss compounds an already-compromised optic nerve |
| Greater depth of focus, greater miss sensitivity | Long eyes miss target more often, shifting the whole focus range |
| No glaucoma-specific safety data | None at any severity |
| Pupil-dependent performance | Future glaucoma drops that shrink the pupil could degrade distance vision |
PureSee is an exciting, well-designed, non-diffractive lens, but these five points make it the wrong fit for this particular eye.
If we did choose the Eyhance Toric II instead: the target plan
| Eye | Recommended target | Why |
|---|---|---|
| OD (first, non-dominant) | −0.25 to −0.50 D | Sits in the Eyhance sweet zone (distance sharp to ~−1.1 D), buffers the hyperopic shift, keeps the eyes close together for a glaucoma patient |
| OS (second, dominant) | Plano, adjusted after seeing the OD result | Optimizes distance; if OD drifts, OS can be nudged into gentle micro-monovision |
The bottom line for you, the patient
| Your situation | What we usually favor |
|---|---|
| Fine with glasses | Monofocal, excellent and covered by insurance |
| Drive at night, dislike halos | Avoid diffractive multifocals |
| Have astigmatism | Light Adjustable Lens, tuned after healing with nothing to rotate |
| Have glaucoma | Monofocal, enhanced monofocal, or Light Adjustable Lens to protect contrast and clean visual fields |
| Very nearsighted | Confirm the lens comes in a low enough power, and plan for adjustment |
There is no perfect lens, only the best lens for your eyes, your life, and your night driving. That is the conversation I want to have with you in the office.
The bigger picture: where each lens family fits
Complete multifocal IOL reference list
| Category | Representative models | Optical type | Notes |
|---|---|---|---|
| Diffractive bifocal | AcrySof IQ ReSTOR +2.5 / +3.0; TECNIS Multifocal ZMB00 / ZLB00 | Diffractive | Classic bifocals; reduce mean deviation and foveal threshold in glaucoma |
| Diffractive trifocal | AcrySof IQ PanOptix; TECNIS Synergy; AT LISA tri 839MP; FineVision POD F | Diffractive | Popular; wide range but highest risk of visual field depression |
| Diffractive EDOF hybrid | TECNIS Symfony | Diffractive EDOF | Technically EDOF but diffractive; minimal field impact; behaves like a monofocal |
| Refractive multifocal | Lentis Mplus; Oculentis Mplus X | Refractive | Sector-shaped zones; fewer rings; less glare |
| Older refractive multifocal | Array SA40N; ReZoom | Refractive | Early designs; more halos; rarely used now |
| Segmented multifocal (toric) | Lentis Mplus toric | Refractive | Sector multifocal with astigmatism correction |
| Multifocal toric | PanOptix Toric; Synergy Toric; TECNIS Multifocal Toric | Diffractive | Multifocal plus astigmatism correction |
Where monofocals and the LAL fit
| Lens type | Examples | Optical type | Notes |
|---|---|---|---|
| Monofocal | TECNIS 1-Piece; AcrySof IQ; Clareon | Refractive | Best for glaucoma visual field reliability |
| Enhanced monofocal | TECNIS Eyhance | Refractive | Small built-in intermediate boost; glaucoma-validated |
| Light Adjustable Lens | RxSight LAL and LAL+ | Refractive | Adjustable monofocal; minimal field impact; best for residual astigmatism |
References
- Miller KM, et al. Cataract in the Adult Eye Preferred Practice Pattern. Ophthalmology. 2022;129(1):P1-P126.
- Zhu X, et al. Early Transient IOP Spike After Cataract Surgery in Highly Myopic Eyes. Br J Ophthalmol. 2020;104(8):1137-1141.
- Lidder AK, et al. IOP Spike Following Stand-Alone Phacoemulsification in the IRIS Registry. Ophthalmology. 2024;131(7):780-789.
- Laube T, et al. Pseudophakic Retinal Detachment in Young-Aged Patients. PLoS One. 2017;12(8):e0184187.
- Thylefors J, et al. Retinal Detachment After Cataract Surgery: A Population-Based Study. Acta Ophthalmol. 2022;100(8):e1595-e1599.
- Qureshi MH, Steel DHW. Retinal Detachment Following Cataract Phacoemulsification, a Review. Eye (Lond). 2020;34(4):616-631.
- Miller KM, et al. Cataract in the Adult Eye Preferred Practice Pattern. Ophthalmology. 2022;129(1):P1-P126.
- Yao Y, et al. Efficacy and Complications of Cataract Surgery in High Myopia. J Cataract Refract Surg. 2021;47(11):1473-1480.
- Felipe A, et al. Residual Astigmatism Produced by Toric IOL Rotation. J Cataract Refract Surg. 2011;37(10):1895-1901. (with Li ES, et al. 2024 rotational-stability meta-analysis; Lam CC, et al. 2026)
- Holladay JT, Haller M. Light-Adjustable Lens FDA Post-approval Study. J Cataract Refract Surg. 2026;52(7):666-669.
- Kang S, Hsu J, Yoo SH. Pseudophakic Mini-Monovision. Surv Ophthalmol. 2026;71(3):973-979.
- Doane J, et al. Registry Comparing Two Light Adjustable Lenses. J Cataract Refract Surg. 2025;51(11):948-954.
- Gedde SJ, et al. Primary Open-Angle Glaucoma PPP. Ophthalmology. 2026;133(4):P1-P103.
- Nam JW, et al. Enhanced vs Standard Monofocal IOL in Early Glaucoma. J Clin Med. 2023;12(18):5830.
- Kim H, et al. Enhanced Monofocal IOL in Glaucoma of Varying Severity. Sci Rep. 2025;15(1):4737.
- Corbett D, et al. Quality of Vision for a Fully-Refractive EDOF IOL (PureSee). Eye (Lond). 2024;38(Suppl 1):9-14.
This article is general educational information from Visionary Eye Doctors and is not a substitute for a personal examination. Every eye is different. Your surgeon will individualize your lens choice, targets, and risks to your specific measurements.
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