Accommodating IOLs
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| Click here and then select “How an Accommodating IOL works” |
Enable patients to change their focus from distant to intermediate or near objects. Accommodating IOLs:
- Utilize the eye’s internal muscles to shift focus by slightly changing the IOL shape or position
- Do not need to split light between various points to achieve their function, unlike multifocal IOLs
- Overall image quality is expected to be slightly superior with an accommodating IOL, as compared to a multifocal IOL.
Advantage
High quality of vision because light is not split between different focal points.
Disadvantage
Some patients may not achieve sufficient accommodation to perform all near tasks with currently available accommodating intraocular lenses.
Th Eyeonics CrystaLens:
The FDA approved the CrystaLens for the replacement of the natual lens after cataract surgery in November 2003, as an accommodating intraocular lens that can provide near, intermediate and distance vision without spectacles. In all, 497 eyes in 324 patients at least 50 years old with cataracts were implanted with lens. The mean age of the study patients was 69.7 years. FDA approval was based on clinical trial evaluations that showed the following:
Survey of patients in which lenses were implanted in both eyes
Activities Without Spectacles
| Activity |
Yes |
No |
| Perform most visual functions |
93.8% |
6.3% |
| Read most things |
77.5% |
22.5% |
| Go shopping |
93.5% |
6.5% |
| Participate in sports |
96.6% |
3.4% |
| Attend social gatherings |
95.2% |
4.8% |
| Drive |
91.7% |
8.3% |
| Read a newspaper |
57.0% |
43.0% |
| Sew or do needlework |
38.5% |
61.5% |
| Work on a computer |
80.6% |
19.4% |
| Do handy work around the house |
94.4% |
(5.6% |
| Walk |
97.7% |
2.3% |
| Shop |
91.4% |
8.6% |
| Watch television |
92.3% |
7.7% |
The following table reports on the percentages of patients who experienced difficulty with activities done at night.
Bilateral Patient Survey
Difficulty With Night Activity (US Bilateral Subjects)
| Symptoms |
Moderate |
Severe |
| Night-time glare/flare |
13.8% |
5.4% |
| Night vision: difficulty driving at night |
11.6% |
3.3% |
| Halos (rings around lights) |
12.3% |
6.2% |
Source: U.S. FDA, Summary of Safety and Effectiveness Data, (pdf)
Get the Facts: Precision and Sharpness of Vision
- Patients should note that the formulas used for calculating the power of IOLs are reasonably accurate, but not necessarily as precise as those used for computing laser-based vision correction treatments.
- It is not unreasonable to expect that patients, especially those with severe nearsightedness or astigmatism, may require a combination of lenses, surgical incisions and laser-based procedures (LASIK), collectively called "bioptics," to achieve a desired visual result.
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