As optometrists, there are few things more disheartening than having to dismiss a patient’s interest in improving their vision, especially when it’s due to a lack of available technology.
In the past, this was often the result of a patient who was interested in trying contact lenses for the first time or returning to wear but bore a considerable prescription. Those presenting with astigmatism were most commonly impacted, secondary to limited parameters or clinician comfort fitting toric lenses.
Given the fantastic toric contact lens options presently available, parameter limitations are no longer a common issue. Clinicians will rarely find themselves without a soft contact lens option for their patients. Not only are the options plentiful, but the lenses are also healthy, comfortable, and easy to fit.
Personally, I am most comfortable speaking on the CooperVision lens line. Over the past decade, I have heavily prescribed and discussed their lenses as well as trained dozens of doctors a year on these products. In this piece, I emulated my teachings, which reflect my clinical support of the CooperVision Biofinity toric lens.
Provider hesitations with toric lenses
Though toric lenses can provide superior vision for patients presenting with astigmatism, some practitioners are hesitant to try toric lenses. There is still a trend for optometrists to shy away from fitting a toric lens when not entirely necessary. Toric contact lenses are only utilized in approximately 25% of patients, though 47% of patients can benefit from their use.1,2
Clinicians may attempt to fit a spherical option as the first lens choice in patients with lower-moderate cylindrical corrections, utilizing the prescription’s spherical equivalent to avoid toric contact lens use. Along the same lines, patients may have reservations stemming from misconceptions that were raised by the patient’s family, friends, or online sources.
Both practitioners and patients often report the same reasons for avoiding toric contact lenses:
- Too expensive
- Uncomfortable
- Unreliable
- Increased chair time
- Not available in the necessary power
- The belief that a spherical lens is just as good
Addressing astigmatism with toric lenses
Frequently, patients who are interested in contact lenses present with the need for some level of astigmatic correction. Approximately 47% of patients suffer from 0.75 diopters (D) of astigmatism or more in at least one eye.1 It’s essential to correct this astigmatic error, even in low astigmatic corrections with your initial diagnostic lens, rather than attempt to achieve potentially adequate vision with a spherical alternative.
The importance of correcting even low astigmatic error was emphasized when Richdale et al. observed that both low- and moderate-astigmatic eyes showed superior acuities when utilizing a toric contact lens compared to its spherical alternative.3
They found that eyes with under a diopter of astigmatism demonstrated up to one full line of visual acuity improvement when utilizing a toric lens, whereas moderate-astigmatic eyes displayed an even greater improvement of 8.5 to 12.5 letters when utilizing a toric contact lens compared to its spherical counterpart.3
Using toric lenses to provide patients with optimal vision
Not only does correcting a patient's astigmatic error lead to objective improvements in visual acuity, but patients' perceptions are also significantly impacted. When evaluating the success of fitting low astigmatic myopes with spherical versus toric contact lenses, Dabkowski et al. found that 71% of patients indicated that they preferred the toric contact lens over the spherical alternative.4
As such, it’s important to lead with an initial diagnostic contact lens that will provide the patient with their best possible vision to save valuable chair time and the patient the inconvenience of returning for unnecessary follow-ups.
Patient follow-up compliance, annual return rate, and care regimen can be enhanced when a patient’s vision is optimized and they see as well—or better—with their lenses compared to their spectacles.5-6 This can most successfully be achieved by correcting both the patient's spherical and astigmatic refractive error.
The end result is improved patient vision and satisfaction, reduced follow-up chair time, and the first steps to ensuring a lifelong patient.
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Contact Lens Guidelines for Astigmatic Patients
Use this handout to provide astigmatic patients with guidance on how to insert, remove, and take care of their contact lenses to streamline the education process.
Educating patients on the value of toric lenses
The first step to ensure success with these individuals is to educate the patient on the visual benefits of a toric contact lens—even when managing patients that present with what's traditionally seen as low levels of astigmatism.
Since correcting an astigmatic correction as low 0.75D can yield significantly improved acuities,3-4 emphasizing this potential level of visual improvement when utilizing a toric contact lens is critical for patient buy-in.
When patients ask why they should opt for a toric lens over a spherical option, I often ask them: “Would you wash two-thirds of your car or paint just half of your house? That would be absurd, wouldn't it? So why would we only correct two-thirds of your prescription?”
By offering a basic level of patient education, you can alleviate concerns, increase the chances of compliance, and decrease drop-out.
1. Explain that, for best vision, astigmatism must be corrected
Explain that correcting their astigmatic refractive error will provide the patient with their best correctable vision. Inclusion of the patient’s astigmatic correction can improve their vision for the most demanding elements of their life—activities such as driving and reading detailed print (whether that’s a book or a baseball game score will be far easier if their astigmatism is corrected.
By correcting their astigmatism, you can improve all elements of their vision, both near and far.
Point out the bonus benefit of glare reduction
The silver bullet is usually discussing improved nighttime glare. Car headlights are most definitely the bane of every patient with uncorrected astigmatism. It’s important to educate patients that astigmatic corrections will improve or eliminate this impactful visual disturbance.7
Make certain to emphasize that a toric lens will provide enhanced clarity for all activities and, though a spherical lens could be used, a toric lens provides the advantages that will help ensure a successful fit and clear vision.
2. Provide clarity on exactly how toric lenses work
After a patient understands that a toric lens will provide them with superior vision, their next question is often, “How do they work?” Many patients have heard that toric lenses stay in place secondary to a thick-weighted lens, which may compromise both comfort and reliability.
It’s essential to explain that modern toric lens technology has come a long way. The general concept may be the same; however, extensive research, trials, and development have gone into creating a new generation of contact lenses that can achieve clear vision without sacrificing comfort or reliability.8 As an example, the Biofinity Toric utilizes Optimized Toric Lens Geometry, which incorporates multiple different lens design components.
To assist the lens in swiftly settling in place, sit in the correct orientation, minimize rotation, enhance comfort, and provide stellar vision, the Biofinity toric lens utilizes a uniform horizontal thickness, wide ballast band, unique back surface curvature, and large toric optic zone to achieve the necessary goals and reliably ensure a successful contact lens fit.9
It’s important to communicate that all these elements come together and synergistically enhance the patient experience.
3. Inform them why you have chosen a specific lens for them
Of course, there are a number of different toric lens designs available, as outlined in the table below.
Table 1: List of available toric lens designs with key parameters.
Table 1: Courtesy of Robert Africano, OD, FAAO.
However, my practice’s go-to lens is traditionally CooperVision’s Biofinity Toric. I had great patient success fitting this lens. Also, in a multinational survey of eyecare professionals, the Biofinity Toric was identified as the most recommended reusable soft toric contact lens, so I can feel confident in my decision and know that I am setting my patient up for the greatest chance of fit success.9-10
4. Alleviate concerns about reliability and clarity
There may also be concerns on a toric lens' ability to maintain consistent and clear vision; patients may report that they have heard from a friend or family member that their vision has come in and out of focus when they have used a toric lens in the past.
As well, clinicians may have experienced a poor fit and developed the misconception that toric lenses are consistently inconsistent. Fluctuating vision is a potential obstacle with toric contact lenses, if fitted incorrectly.
It is essential that a lens rotates marginally with each blink; however, if excessive rotation occurs, that may indicate an incorrect base curve or poor overall fit. Fortunately, many lens brands have design elements to minimize rotation and achieve a stable, reliable fit that yields clear vision.
For example, the Biofinity Toric utilizes a wide ballast design and uniform horizontal thickness to enhance rotational stability. This keeps the lens stable on the eye during blinking by creating equal lid force across the lens, thus ensuring that the lens sits in place consistently throughout the day, which provides clear and stable vision.9
A note on underlying ocular conditions
Note that often, when patients do report fluctuating vision, it's commonly associated with something other than the lens fit. If a patient presents with papillae associated with allergic conjunctivitis or, in its most severe form, giant papillary conjunctivitis, the patient can experience excessive lens rotation and movement.
However, managing the underlying etiology through topical and potentially oral antihistamines is essential to restore lens stability and clarity as well as patient comfort. A short-term discontinuation of contact lens wear can also be beneficial to assist in a swift resolution
Dry eye syndrome can also be associated with fluctuating vision. A patient reporting improved vision, via blinking rather than blur, is traditionally indicative of ocular surface disease rather than excessive lens movement. When a poor fit is the culprit, blinking traditionally displaces the lens, thus inducing blur.
Dry eye is commonly associated with short-term vision improvement after blinking or rubbing, along with worsened symptoms towards the end of the day or after prolonged near work. As such, the focus should be on managing the patient’s ocular surface health to ensure a successful lens fit.
Adjusting contact lenses for ocular conditions
Often, the best course of action when ocular surface disease or allergies are negatively impacting a fit would be a lens modality change.
Moving to a daily disposable lens—from a 2-week or monthly disposable lens—can yield improvement in a patient's vision and comfort as well as help resolve the underlying etiologies.11 The daily disposable lens modality is the champion of patients who are suffering from ocular surface complications.
In the case of consistent blur associated with a misaligned lens orientation, don’t neglect to utilize the LARS adjustment method to modify the patient’s prescription to ensure optimal clarity. As such, the clinician would modify the patient’s contact lens prescription to compensate for the level of misalignment and rotation.
Note: It’s important to keep in mind the “Left Add, Right Subtract” is from the perspective of the clinicians left and right and not that of the patient.
5. Address the misconception that toric lenses are uncomfortable
There can be an impression that toric contact lenses are associated with poor comfort secondary to their design and size. The first thing to consider is a toric contact lens’ size. Patients often refer to toric contact lenses as if they are trying to insert a frisbee into their eye.
However, I explain that often, toric lenses are just a fraction of a millimeter larger than their spherical counterparts. That fact dramatically alters the patient’s perspective of the lens. Advanced lens designs and materials mean patients no longer need to sacrifice all-day comfort for clarity.
6. Assure them that toric lenses are a valid choice for high astigmatism.
Some patients may be worried that a toric contact lens might not be right for them due to the magnitude of their astigmatism. As a clinician, it’s important to be aware of the availability of present lens parameters to both fit and educate our patients on the best lens options.
Whether it’s a -2.75 cylindrical correction—provided by lenses like the Total 30, Acuvue Oasys, Bausch + Lomb Ultra, and Biofinity XR Toric Lenses—or the extended parameters provided by the Biofinity XR Toric that can correct up to -5.75D of astigmatism, nearly all astigmatic prescriptions have a soft lens option.
Secondary to modern lens design, high astigmats yield far more successful fits with increased lens stability.
7. Communicate that this modality is appropriate for their lifestyle.
It’s important to address that there is a toric lens option for nearly every lifestyle and activity, be it for work or leisure. Also, keep in mind that we have toric lens options ranging the full spectrum of replacement schedules.
To provide the healthiest and optimal option, educate patients interested in occasional lens wear (who simply need lenses for specific activities) or those impacted by ocular surface disease on the benefits of toric daily replacement lenses.
Of course, there is a wide range of choices for traditional 2-week and monthly toric contact lens wearers available as well. Lastly, presbyopic patients can’t be forgotten; we have the option to provide a stellar toric multifocal or toric monovision fit to meet both their distance and near needs.
Final thoughts on setting the stage for success
After educating a patient on the technological advancements in lens materials, versatility in wear modalities, and quality of vision provided, it is important to work together with them to determine the best possible contact lens option.
It’s a practitioner's responsibility to correct a patient’s vision to the best of their ability and provide each patient with the best chance of visual success. Given that there is no shortage of toric contact lens options available, this is now more attainable than ever.
So, the next time a patient asks for their spherical equivalent, make sure to discuss the benefits a toric lens could provide to make a blurry world a little clearer, one eye at a time.
3 additional takeaways on toric lenses
- Price point can sometimes be a critical component in a patient’s decision. Fortunately, most toric lens prices do not differ dramatically from their spherical counterparts—so, often, the decision is not if we should utilize a toric lens, but which brand and modality.
- Never forget that if the first fit isn’t optimal, try, try again. Utilize the LARS adjustment method and try different lens materials or brands.
- Listen to your patient's struggles to determine if ocular surface disease or ocular allergies are at fault.
