SupraCor and LASIK Monovision Laser Vision Correction both involve trading some distance vision to improve mid and close vision. Both can be used after cataract surgery or to correct presbyopia. A new study looks at SupraCor after cataract surgery.
In my last blog, I looked at the issue of reading vision after cataract surgery. We talked about how patients can choose either a monofocal lens implant which does not correct reading vision — or multifocal implants that can correct reading vision and distance vision simultaneously.
The benefit of a monofocal lens is that it can provide better distance vision than a multifocal lens, particularly under dim light. However, other than the case of accomodating “premium” monofocal lenses, the close vision is poor with monofocal implants without the use of reading glasses. One problem with multifocal implants is that if the patient does not like the distance vision they provide, it is a substantial issue to remove them and replace them with monofocal lenses. While this can be done, the risk is not trivial. For this reason, many patients opt for monofocal implants. Yet, some of these patients who select monofocal implants are not satisfied with their near vision. Its all a matter of trade-offs.
One option for patients who are dissatisfied with their near vision after cataract surgery with monofocal lens implantation is to subsequently have LASIK or PRK to bring the non-dominant eye “in” as a better reading eye. This, of course, involves a degree of trade off in which some distance quality is sacrificed to gain near vision. Again, another trade-off. Fortunately, this trade off can be demonstrated to the patient with a contact lens simulation before the choice is made to have LASIK or PRK to create a degree of monovision.
There is now another laser vision correction option for improving close vision other than LASIK or PRK currently under FDA clinical evaluation: SupraCor. SupraCor is a laser technique in which the excimer laser is used to sculpt a multifocal shape in the cornea. It can be used after monofocal cataract surgery. In theory, it may provide the benefits of monovision without as much downside to distance vision. On the other hand, it may not end up providing near and distance performance which truly is better than monovision.
A new study looked at the use of SupraCor after cataract surgery with monofocal lens. This study, by Robert Edward Ang, M.D., was presented at the Asia-Pacific Academy of Ophthalmology and All-India Ophthalmological Society. In Dr. Ang’s study, 35 patients who had previously had cataract surgery with monofocal implants underwent SupraCor treatment in one eye. Only healthy eyes were included in the study. Results showed that intermediate range vision was excellent: 95% of eyes had vision equivalent to 20/25 or better at intermediate distances. Close vision was not quite as good as only 64% of patients achieved 20/25 equivalent or better at close range. There was some distance trade-off as 31% of patients lost one line of distance visual acuity, consistent with the multifocal nature of the SupraCor treatment. Results were very stable over time.
In looking at this data, it is not clear to me that the SupraCor will, at this point, offer a substantial advantage over a mild degree of mid-monovision, which is also called “blended vision.” Both blended monovision and SupraCor appear to prioritize the mid range vision over the very close near vision. Both involve some compromise to both near and far, but it is not clear which involves more compromise. A side by side study will be necessary to determine the relative merits of the two approaches. One advantage of monovision and blended LASIK monovision vision over SupraCor, theoretically at least, is that they are easier to reverse if the patient would like to go back to optimal distance vision and wearing reading glasses. Furthermore, it is easier to simulate monovision or blended monovision with simple contact lenses before surgery than it is to simulate SuprCor multifocal vision.
SupraCor is an interesting concept, but like many multifocal approaches, it is a tradeoff and its downsides will need to be more fully understood in comparing it to various degrees of LASIK or PRK monovision.
See Also
Presbyopia SupraCor Treatment for Myopic/Hyperopic Pseudophakic Eyes (SUPRACOR)
FDA clinical trial synopsis for SupraCor use after cataract surgery.
Cataract Surgery After IntraCor and SupraCor
A review of techniques for implanting intraocular lenses after IntraCor and SupraCor laser vision correction.
SupraCor
Technolas website for SupraCor
Reporting Live from the Asia-Pacific Association of Cataract and Refractive Surgeons Meeting
An international ophthalmology symposium discussing SupraCor’s use to improve near vision.
APAO-AIOS
Asia Pacific Academy of Ophthalmology and the All India Opthalmological Society
Surgery for Presbyopia
All About Vision discussion of monovision and other surgical approaches to presbyopia correction and improvement of near vision.