Cataract surgery continues to evolve rapidly, with more and more patients electing to undergo refractive cataract surgery. Refractive cataract surgery encompasses a wide array of techniques, technologies and lens options designed to provide patients with the opportunity to reduce spectacle dependence.

In this article, I will discuss how astigmatism management and presbyopia-correcting IOLs are utilized to reduce spectacle dependence. I will also discuss how refractive cataract surgery is conceptualized in various practices and our specific implementation at UCLA.

THREE RULINGS 

Three CMS Rulings cover the space of refractive cataract surgery: CMS National Coverage Determination 80.7 (1997),¹ CMS ruling 05-01 (2005)² and CMS ruling 1536-R (2007).³ These rulings cover refractive keratoplasty, presbyopia-correcting IOLs and astigmatism-correcting, or toric, IOLs, respectively. The rulings allow for placement of presbyopia-correcting IOLs or astigmatism correction by various techniques at the time of cataract surgery.

These rulings discuss how non-covered facility and physician charges should be handled. For example, CMS Ruling 05-01 states: “The beneficiary is responsible for payment of that portion of the facility charge that exceeds the facility charge for insertion of a conventional IOL following cataract surgery.” This statement generally refers to the cost of a presbyopia-correcting lens.

It goes on to state: “The beneficiary is responsible for payment of that portion of the physician’s charge for the presbyopia-correcting IOL that exceeds the physician’s charge for a conventional IOL following cataract surgery.” This statement generally refers to professional payment covering the additional imaging, surgical planning and surgical time required to successfully implant a presbyopia-correcting IOL.

The rulings for toric IOLs and refractive services at the time of cataract surgery are similar. Let’s try to better understand astigmatism correction and presbyopia-correcting lenses.

ASTIGMATISM MANAGEMENT

Benefits, patient selection

The first element of refractive cataract surgery is astigmatism management. This is a surgical service that is rendered at the time of cataract surgery and/or postoperatively as an enhancement option. Correcting astigmatism at the time of cataract surgery offers several significant benefits for vision and can be offered to nearly all patients, with little to no downside. The benefits include improved visual acuity, improved contrast sensitivity, improved night vision, decreased lifetime eyeglasses cost and increased patient satisfaction. 

It is rare that a patient would not benefit from astigmatism management, though the prevalence of non-eligible patients is higher at a tertiary referral center such as UCLA Health. For example, we rarely recommend astigmatism management when patients have limited post-operative vision potential due to conditions including amblyopia, retinal detachment or advanced glaucoma. In these cases, correcting astigmatism would not appreciably improve final visual acuity to justify the higher expense to the patient.

In UCLA Health’s refractive cataract surgery model, physicians are not paid any additional professional fee to implant a presbyopia-correcting or toric IOL. The benefit of this model is that physicians do not face potential conflicts of interest in deciding which lens to recommend at the time of cataract evaluation. Instead, the primary encouragement is to offer patients astigmatism management, a service with significant benefit to nearly all patients and essentially no drawbacks.

The surgical options

Astigmatism management can be achieved in one of many ways:

1. On-axis incisions. On-axis incisions are a surgical technique used for the management of smaller amounts of astigmatism during cataract surgery. These incisions, also known as steep-axis incisions, are primary incisions placed on the cornea to reduce astigmatism along its steepest meridian.
2. Peripheral corneal relaxing incisions (PCRIs). PCRIs involve making small, arc-shaped incisions at the limbus (the junction between the cornea and the sclera) to flatten the steeper meridian of the cornea, reducing astigmatism. PCRIs are generally created with a diamond blade or with the assistance of femtosecond laser technology.
3. Toric IOLs. These lenses are generally offered when astigmatism is higher than >0.75 D against the rule or >1.0 D with the rule, though lower power torics are becoming more widely available. Proper topographic measurement of the cornea is always obtained, and high-quality biometry is essential to ensuring great outcomes and happy patients.
4. Femtosecond laser-assisted cataract surgery (FLACS). FLACS is a laser approach to cataract surgery that allows for highly precise incisions, PCRIs, capsulorhexis and lens precutting. Specifically for astigmatism management, the femtosecond laser can create corneal incisions, including PCRIs, with high accuracy. 
5. Postoperative refractive management. In certain cases, astigmatism management is not addressed during cataract surgery. These cases include instances when astigmatism measurement is challenging prior to cataract surgery or postoperative outcomes are challenging to predict. In these situations, astigmatism can be managed postoperatively using eyeglasses, contact lenses or additional refractive procedures such as laser vision management (eg, LASIK, PRK or SMILE). 

How to choose

Many ophthalmologists use a stepladder approach to astigmatism management that tailors the treatment performed to the amount of corneal astigmatism present on topography or tomography.⁴ Astigmatism management can be offered to any patient regardless of the lens that will be implanted, including a monofocal. Astigmatism management and spherical power “touch ups” can be extended into the postoperative period by applying laser vision correction or additional relaxing incisions.

The choice of astigmatism management method depends on several factors, including the degree of astigmatism, patient preferences, surgeon expertise and the availability of technology.

PRESBYOPIA CORRECTION

Astigmatism management first

The second element of refractive cataract surgery is the treatment of presbyopia by the implantation of an extended depth of focus, presbyopia-correcting or accommodating lens device. Because postoperative astigmatism must be low for optimal performance of presbyopia-correcting IOLs, these devices are almost always paired with an astigmatism management service. Most presbyopia-correcting lenses come in toric versions. Astigmatism management and specialty IOLs are the sum total of refractive cataract surgery.

The presbyopia-correcting IOL option

In many practices that offer refractive cataract surgery, a presbyopia-correcting lens is presented strongly as the refractive cataract surgery option. These lenses have gained popularity due to their potential to reduce spectacle dependence. However, downsides — including glare, halos and reduced contrast sensitivity — can significantly impact patients’ quality of life and satisfaction with the procedure.

Additionally, not all patients are ideal candidates for presbyopia-correcting IOLs, as those with other ocular comorbidities may not achieve the desired outcomes. Proper patient selection and informed consent are crucial when considering these presbyopia-correcting IOLs. 
Although these lenses are offered at UCLA Health, the percentage placed is less than 10% across the institute. Instead, the focus is on patient education and management of astigmatism at the time of cataract surgery.

Mini-monovision

At UCLA Health, we also rely heavily on mini-monovision: By targeting the non-dominant eye for better intermediate vision, patients can often achieve functional intermediate vision. Mini monovision aims to provide a reasonable compromise between near and distance vision, offering patients the convenience of reduced dependence on reading glasses while maintaining acceptable distance vision. In the mini monovision approach, the dominant eye is targeted for plano and the non-dominant eye is generally targeted for -0.75 D or -1.00 D. This generally allows patients to see 20/25 or 20/30 with the non-dominant at distance, and J4-J7 at near.

Other approaches we offer include true monovision and presbyopia-correcting IOLs. We are hopeful that the next generation of accommodating IOLs will offer benefits for patients without the downsides of today’s presbyopia-correcting lenses.

PATIENT COMMUNICATION

When speaking to patients about refractive surgery services, it is important to choose words carefully. For example, never tell a patient you will “correct” their astigmatism; you will be setting yourself up for a disappointment. For example, if a patient has 1.6 D of cylinder at 180° preoperatively and 0.25 D of cylinder at 90° both by keratometry and topography postoperatively, you will think you achieved a great result — and you did! However, the patient will perceive it differently. “You said you were going to correct my astigmatism. Why do I still have it?” Human biology and healing can never be perfectly predicted, and we try to help our patients understand this as well as possible prior to cataract surgery. 

Another mistake is to call your service “astigmatism reduction.” This simple word change would cover the case above, but it would not cover all scenarios. Let’s look at the most 
extreme example: the cornea with no measurable astigmatism preoperatively. Can you “correct” or “reduce” the astigmatism of a cornea with 0 D of preoperative astigmatism? Of course not. If a patient with 0 D of corneal astigmatism needs surgery, you will have to make a corneal incision to remove the cataract and implant a lens. That incision will almost certainly induce some astigmatism, even if you counter it with a matching incision 90° away.

Here is a question: In the 0-D astigmatism case, does it matter where you make the phacoemulsification incision? Probably! If it was a cataract surgeon’s eye, most of them would want that incision to be placed in the 0° or 180° meridian to affect a “with-the-rule” change because, over the rest of their life, that incision location will provide the best long-term result. 

As we age, our astigmatism tends to drift from vertically steep (with-the-rule) to horizontally steep (against-the-rule). Creating a little vertical corneal steepness in the short term will affect the best long-term result, even though we will have infinitesimally worsened the cornea’s astigmatism. In this 0-D astigmatism example, we can neither correct nor reduce the astigmatism of the eye, but we can “manage” it in a way that produces the best long-term benefit for the patient. 

Thus, the term “astigmatism management” is much better than “astigmatism correction” or “astigmatism reduction” because it covers these various scenarios and helps patients understand our long-term plan for their vision.

IMPROVING QUALITY OF LIFE 

Astigmatism management has witnessed remarkable advancements in both diagnostic tools and treatment options. Our commitment to managing astigmatism during cataract surgery allows us to satisfy our patients’ desire for improved vision while minimizing negative side effects. The ability to simultaneously address cataracts and astigmatism not only enhances visual outcomes but also significantly improves the quality of life for our patients.  OM

References 
1. CMS National Coverage Determination §80.7 Refractive Keratoplasty
2. CMS Ruling 05-01 Presbyopia-correcting intraocular lens, May 2005
3. CMS 1536-R Astigmatism-correcting intraocular lens, January 2007
4. Amesbury EC, Miller KM. Correction of astigmatism at the time of cataract surgery. Curr Opin Ophthalmol. 2009 Jan;20:19-24.

Shawn R. Lin, MD, is medical director at UCLA Stein Eye Center in Calabasas, Calif., where he specializes in precision cornea, cataract and refractive surgery. Contact him at slin@jsei.ucla.edu. Dr. Lin did not reveal any relevant disclosures.