Is the ALCON ARGOS biometer measurement uncomfortable or invasive?

No. The ARGOS is fully non-contact. Nothing touches the eye, the scan is painless, and each eye is measured in about a second. Because nothing touches the surface, there is no risk of corneal indentation and a lower risk of cross-infection compared with contact ultrasound biometry.

How does the ARGOS biometer improve cataract surgery outcomes?

Accurate biometry is the single biggest driver of a predictable result. The ARGOS uses a sum-of-segments method that applies a separate refractive index to each part of the eye, improving axial length accuracy in long and short eyes. Combined with expert formula selection, this helps the surgeon choose an IOL power that lands closer to target and reduces the chance of needing glasses after surgery.

Can the ARGOS measure eyes with dense or advanced cataracts?

Yes. The ARGOS uses a longer 1060 nm wavelength and a wide scanning beam that penetrates cloudy lens tissue, so it can obtain a reading in dense cataracts where older biometers often fail. In a published dense-cataract study the ARGOS achieved a 100% axial length acquisition rate, and in very dense grade-3-or-higher cataracts it maintained a high success rate where partial-coherence devices dropped substantially.

ALCON ARGOS Biometer

Q: Does the surgeon or the technology matter more for cataract surgery?

Both matter, but they are not equal. Advanced technology like the ARGOS produces excellent raw measurements, yet those measurements still have to be interpreted: which IOL formula fits this particular eye, which lens suits this patient's life, and where to cross-check. That expert judgment is what turns a great measurement into your best possible result, which is why CCRS emphasizes mastery of technology, not just ownership of it.

Q: What is sum-of-segments axial length?

Sum-of-segments is a more precise way to measure the length of the eye. Instead of applying one average refractive index to the whole eye, the ARGOS measures the cornea, aqueous, lens and vitreous separately, applies the correct refractive index to each segment, then adds them together. This better reflects how each eye is actually built and improves IOL power accuracy, especially in unusually long or short eyes.

Q: Does the ARGOS biometer work for refractive lens exchange?

Yes. Refractive lens exchange uses the same lens-replacement principle as cataract surgery, so the same precise biometry applies. Accurate measurements are especially important here because RLE patients often choose premium multifocal or extended-depth-of-focus lenses that demand a tight refractive result.

At California Center for Refractive Surgery, our commitment is simple: the best vision your eyes are capable of. The ALCON ARGOS biometer is one of the most advanced eye-measurement instruments in the world — but a great instrument only becomes a great result in experienced hands.

Home | ALCON ARGOS Biometer

That is the difference at CCRS. We don't just invest in the finest technology for cataract surgery and refractive lens exchange — we've mastered it, so every measurement is turned into the right lens choice for your eyes and your life.

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Full-eye scan, per eye

1060nm

Wavelength that sees through cataracts

100%

Reading rate in dense cataracts

Contact with the eye surface

Our commitment

The best vision your eyes are capable of. That is the only standard we measure ourselves against.

Not the fastest appointment. Not the cheapest lens. The sharpest, most dependable result your eyes can achieve. Every instrument we invest in and every clinical decision we make is judged against a single question: does this give you a better outcome? If it doesn't, it doesn't belong in your care.

— California Center for Refractive Surgery

Our Philosophy

Anyone can buy the technology. Mastering it is rare.

Advanced instruments have become widely available — and that's a good thing. But a device doesn't deliver an outcome; it delivers data. The ARGOS produces some of the most precise measurements in ophthalmology, yet those numbers still have to be read correctly: which lens formula fits this eye, which implant suits this person's life, where to trust the reading and where to verify it. That interpretation is the work of experience, and it's where results are won or lost. We don't simply own the best technology — we've spent our careers learning to extract every bit of benefit from it.

Measurements are raw material. Results are built on top of them.

A perfect measurement handed to the wrong formula still produces the wrong lens. The value CCRS adds sits in the layers above the data — the clinical decisions that turn a number into the right implant for you.

It's why two practices with the same ARGOS can arrive at different plans for the same eye. The instrument is a commodity. The judgment applied to it is not.

The Technology

What is the ALCON ARGOS biometer?

The ALCON ARGOS is a swept-source OCT (SS-OCT) optical biometer — among the most advanced eye-measurement instruments available. In under a second it scans the entire eye with a 1060 nm light beam and precisely measures the axial length, corneal power, anterior chamber depth and lens thickness. CCRS surgeons use these measurements to calculate the exact intraocular lens (IOL) power you need — the single most important step toward a sharp, glasses-reducing result after cataract surgery or refractive lens exchange.

Precision By Design

It measures each part of your eye on its own terms.

Older biometers apply one average value to the whole eye. The ARGOS uses a sum-of-segments method: it measures the cornea, aqueous, lens and vitreous separately, applies the correct refractive index to each, then adds them together. Because every eye is built a little differently, this yields a more accurate length — and, in expert hands, a more accurate lens power — especially in unusually long or short eyes.

Cornea n = 1.376

The clear front window that does most of the eye's focusing.

Aqueous / anterior chamber n = 1.336

The fluid-filled space between cornea and lens.

Natural lens n = 1.410

The lens being replaced — its thickness varies most between eyes.

Vitreous n = 1.336

The gel that fills the back of the eye up to the retina.

Mastery In Practice

How our surgeons extract more from the same instrument.

"Mastery" isn't a slogan — it's a set of specific, deliberate decisions we make with your data before a single lens is ordered. Here's what that looks like.

We match the formula to your eye, not to a default

Short eyes, long eyes and eyes with prior LASIK each behave differently. We select from modern IOL formulas — including the sum-of-segments Barrett True Axial Length formula built into the ARGOS — based on your specific anatomy, rather than accepting one setting for everyone.

We use sum-of-segments to its full potential

The ARGOS captures segment-level detail most devices can't. We put that detail to work in the formulas designed to exploit it — the eyes hardest to predict are exactly where this pays off.

We choose the lens for your life, not just your prescription

Monofocal, extended-depth-of-focus or multifocal — the right implant depends on how you read, drive and work. We translate the measurements into a lens matched to how you actually use your vision.

We cross-check before we commit

Precision compounds. We independently verify measurements and calculations, so an outlier reading is caught long before it reaches the operating room.

A surgeon reads your data — not a default template

Interpretation stays in experienced hands from the first scan to the final lens choice. That continuity is the difference between a good plan and your best possible plan.

What It Means For You

Why this pairing matters for your surgery.

Best-in-class measurement, read by experienced surgeons. Here's how that combination shows up in your experience and your result.

Precision where it counts

Sum-of-segments measurement plus expert formula selection drives more accurate IOL power — and a better chance of hitting your target vision.

Fast and comfortable

Each eye is captured in about a second. Less time in the chair, a calmer visit, and no discomfort from the scan itself.

Nothing touches your eye

Fully non-contact scanning means no pressure on the cornea and a lower risk of cross-infection than contact ultrasound.

Works through dense cataracts

A longer wavelength penetrates cloudy lenses, so we get a reliable reading even in advanced cataracts that stump older devices.

Handles unusual eyes

Very long, very short and previously operated eyes are measured accurately — the cases where lens power is hardest to predict.

Ready for premium lenses

The precision premium and multifocal IOLs demand starts here — helping reduce your dependence on glasses after surgery.

The Evidence · Dense Cataracts

It gets a reading when other devices can't.

A cataract clouds the very lens the biometer needs to see through. In a published study of dense cataracts, the ARGOS obtained a successful axial length measurement in 100% of eyes — matching contact ultrasound without ever touching the eye, and out-measuring a partial-coherence device that failed in nearly 4 of 10 eyes.

Axial length acquisition success in dense cataracts

Higher is better · 51 eyes, mean LOCS III grade 3.63

ARGOS (SS-OCT)100%

IOLMaster 700 (SS-OCT)98%

Anterion (SS-OCT)94%

Pentacam AXL (PCI)61%

Ruiz-Mesa et al., Eye and Vision (2023). Swept-source OCT biometers were significantly more successful than partial-coherence interferometry at measuring axial length in dense cataracts.

Why light matters here

The ARGOS uses a 1060 nm wavelength — longer than the 780–840 nm light in many older optical biometers. Longer light penetrates deeper into a cloudy lens, and a wide scanning beam slips around the densest part of the cataract to reach the retina.

In the very densest cataracts (grade 3 or higher), a separate study found the ARGOS held a high success rate where partial-coherence devices dropped to roughly two-thirds of eyes — and its enhanced retinal-visualization mode pushed success higher still.

100%

Axial length acquisition in dense cataracts — no contact with the eye.

Ruiz-Mesa 2023

~86–90%

Of challenging long eyes within ±0.5 D of target using ARGOS + Barrett formula.

Blehm / Shammas

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To capture the full set of biometric measurements, per eye.

Alcon / Shammas

The Evidence · Accuracy

More eyes landing on target — even the hard ones.

"On target" means within ±0.5 diopter of the intended result — close enough that most people function comfortably without glasses for their main task. Historically only about 3 in 4 eyes hit that mark, and long eyes are harder still. Studies using ARGOS measurements with modern formulas report meaningfully higher accuracy in exactly those difficult eyes — which is precisely where formula mastery earns its keep.

The ±0.5 D target

Refractive accuracy depends on two things: the quality of the measurement, and the formula that turns it into a lens power. The ARGOS strengthens the first; our surgeons supply the second — pairing that data with modern formulas built for sum-of-segments biometry, including the Barrett True Axial Length formula.

In one 445-eye analysis, mean prediction error in short eyes improved from 0.45 D to 0.37 D when the sum-of-segments Barrett formula was chosen — a clinically meaningful gain in the eyes toughest to predict, and a clear example of the formula choice mattering as much as the measurement.

Eyes within ±0.5 D of target refraction

Higher is better · long / difficult eyes

ARGOS + Barrett, long eyes~86–90%

General benchmark, all eyes~73%

NHS standard, all eyes55%

Blehm & Potvin, Clinical Ophthalmology (2023/2024); NHS benchmark (2009). Figures describe specific study cohorts; individual results vary with eye anatomy, lens type and formula.

At A Glance

ARGOS swept-source OCT vs. older biometry.

How modern swept-source OCT biometry compares with the partial-coherence and ultrasound methods it replaces.

	ARGOS (SS-OCT)	Partial-coherence optical	Contact ultrasound
Contact with the eye	None	None	Probe touches cornea
Light wavelength	1060 nm (deep)	780–840 nm	Sound, not light
Dense-cataract success	Very high	Often drops	High
Axial length method	Sum-of-segments	Single average index	Single velocity
Scan time per eye	Under a second	Seconds	Longer, operator-dependent
Patient comfort	High	High	Requires numbing drops

Where It Fits

Three steps from measurement to the right lens.

Measure

You rest your chin on the ARGOS and look at a target. In seconds it captures the full map of your eye — painlessly, without contact.

Master

Your surgeon interprets that data — selecting the formula and lens that fit your eye and your life. This is where expertise turns numbers into the right decision.

Implant

The chosen lens — including premium options — is placed during your cataract surgery or refractive lens exchange.

Good To Know

ARGOS biometer: frequently asked questions.

Does the surgeon or the technology matter more?

Both matter, but they aren't equal. Advanced technology like the ARGOS produces excellent raw measurements — but those measurements still have to be interpreted: which IOL formula fits this particular eye, which lens suits this patient's life, and where to cross-check. That expert judgment is what turns a great measurement into your best possible result. It's why CCRS emphasizes mastering technology, not just owning it.

Is the ARGOS measurement uncomfortable or invasive?

No. The ARGOS is fully non-contact — nothing touches your eye. You simply look at a light while the scan runs for about a second per eye. There are no needles, no pressure on the eye, and no discomfort from the measurement itself.

How does the ARGOS improve my cataract surgery result?

Choosing the right lens power is the biggest factor in how well you see after surgery, and that choice is only as good as the measurements behind it. The ARGOS uses a sum-of-segments method that improves axial length accuracy; combined with expert formula selection, this helps your surgeon choose an IOL that lands closer to your target — reducing the chance you'll still need glasses.

Can it measure eyes with a dense or advanced cataract?

Yes. Its longer 1060 nm wavelength and wide beam penetrate cloudy lens tissue, so it can obtain a reading in dense cataracts that often defeat older optical devices. In published dense-cataract studies the ARGOS achieved a 100% axial length acquisition rate and held a high success rate even in the very densest (grade 3+) cataracts.

What is "sum-of-segments" axial length?

It's a more precise way to measure the length of your eye. Instead of applying one average refractive index to the whole eye, the ARGOS measures the cornea, aqueous, lens and vitreous separately, applies the correct index to each segment, and adds them together. Because every eye is proportioned differently, this better reflects your actual anatomy — especially in unusually long or short eyes.

Does the ARGOS work for refractive lens exchange too?

Refractive lens exchange uses the same lens-replacement principle as cataract surgery, so the same precise biometry applies. Accurate measurements are especially important here because RLE patients often choose premium multifocal or extended-depth-of-focus lenses that demand a tight refractive result.

Schedule Your Consultation

The best technology, mastered for your vision.

Book a consultation at CCRS to find out whether cataract surgery or refractive lens exchange — measured with the ALCON ARGOS and guided by our surgeons — is right for you.

Request an appointment Call (323) 933-3111

Candidacy for any procedure is determined during a comprehensive eye examination. Individual results vary based on eye anatomy, lens selection and other clinical factors.