Customized wavefront-guided ablation is producing some of the best-uncorrected
visual results ever achieved with refractive surgery, according to the latest
findings from international clinical trials presented at the XX
ESCRS Congress.
A total of 315 eyes underwent bilateral LASIK following wavefront analysis at
six United States practices. Six-month data is now available for 108 of these
eyes.
The results continued the trend seen at three months. At that time, some 90%
of eyes achieved 20/20 or better and 72% reached 20/16 or better. At the six-month
follow-up, 95% saw 20/20 or better and 73% achieved 20/16 or better.
During both follow-up periods, 19% of patients saw 20/12.5 or better.
Remarkably, many patients achieved better-uncorrected vision postoperatively
than with correction before the procedures. At the six-month follow-up point,
41% of eyes showed better UCVA than the preoperative BCVA. Refractive stability
was reached after one month in 96% of eyes and remained stable thereafter.
Predictability was also good. A full 94% of eyes were within 0.50 D (diopters)
of intended correction at six months. Some 70% of eyes had either a decrease
in high order aberrations or a change of less than 0.10 microns. None of the
eyes lost more than one line of BCVA.
The researchers also recorded patients' satisfaction with the results under
different light conditions. Most people found the treatment very satisfactory.
Indeed, 98% of patients found their vision under bright conditions either satisfactory
or very satisfactory.
Under night vision conditions, patient satisfaction levels were more modest but
better than before the procedure. Some 86% were satisfied or very satisfied;
6% were not sure; and 7% were somewhat dissatisfied compared to 23% preoperatively.
When asked about night vision and glare, 76% said they were satisfied; 16% were
not sure; 7% somewhat dissatisfied; and 1% were dissatisfied. These results again
compare favorably to preoperative values of 24% and 4%, respectively.
The frequency of patients who never or very rarely reported halos improved from
74% preoperatively to 86% at the six-month mark.
A total of eight practices, located in specialist clinics in Europe (Germany,
Spain and UK), South America (Chile and Colombia) and Asia (Korea and Taiwan)
participated in another study.
A total of 288 eyes underwent bilateral LASIK. The surgeons aimed to achieve
emmetropia in
all cases. Review included a one-month follow-up of 163 eyes and a three-month
follow-up of 73 eyes. Mean preoperative refractive error
was -3.0D (diopters) ± 0.7
D for sphere, -0.7 D ± 0.2
D for cylinder, and -3.3 ± 1.0 D.
The amalgamated results paralleled those seen in the United States study above.
One week after the procedure, 84% of patients saw 20/20 or better and more than
half (57%) saw 20/16 or better.
At one month, a similarly high proportion of eyes (81%) achieved 20/20 uncorrected
vision or better and 60% reached 20/16 or better. These results were maintained
at three months, with 84% achieving 20/20 vision or better and 59% reaching 20/16
uncorrected.
Most patients gained one or two lines of best-corrected vision (39% and 21%,
respectively). Predictability, measured at three months, was also excellent.
All eyes were within 1.25 D of the target and 95% of eyes were within 0.5 D of
the expected value. Nearly two-thirds of eyes were within 0.25 D of the goal.
No sight threatening complications were reported.
The correlation among these studies performed by various skilled surgeons worldwide
is a strong testament to this technology's capability and consistency.
