Comparison of monocular implantation of the Acrysof Toric T2 intraocular lens with a standard monofocal intraocular lens in subjects with cataracts and low corneal astigmatism

Cataract surgery and IOL implantation have developed considerably in the past
few years.
Significant numbers of patients having cataract surgery have a degree of
preexisting corneal astigmatism,
Toric intraocular lenses are capable of correcting this astigmatism; they
consist of a spherical and toric component. Toric intraocular lenses are
available in various cylindrical powers: T3 - T9.
At the moment there is considerable interest in correcting lower degrees of
astigmatism; a factor to take into account is surgically induced astigmastim
(SIA). The CE-marked Acrysof Toric SN6AT2 with a cilindrical power of 1.00
diopters (0.68 diopters in corneal plane) has not been used yet; it is
available for this study.
We want to analyse if correction of this low a magnitude of astigmatism can be
accomplished by this toric IOL, and if such correction is clinically meaningful

- Analyse the effect of the toric T2 intraocular lens on quality of vision,
compared to a standard monofocal intraocular lens.
- Analyse the satisfaction of patients with their visual acuity with the toric
T2 intraocular lens, compared to a standard monofocal intraocular lens.

Prospective, double-blind, randomised, within-patient control pilotstudy.

All patients will undergo bilateral cataractsurgery; all surgery will be
performed in the standard way by the same experienced surgeon.
Patients will be their own control. In one eye the standard monofocal IOL will
be implanted; model model Acrysof SNWF. In the other eye the toric T2 IOL will
be implanted; model Acrysof Toric SN6AT2. The lenses have the same design,
except for the minimal cylindrical correction on the posterior surface of the
toric T2 IOL. The side of implantation of the toric T2 IOL will be determined
by randomisation. The surgical technique of implanting both lenses is
identical.

Patients will undergo the standard preoperative measurements, operative
preparations and postoperative measurements. For this study they will have to
answer a short questionnaire pre - and postoperative. They will also visit the
department of ophthalmology 8 weeks postoperative; UCDVA, BCDVA and manifest
refraction will be measured.
Risks of completing the questionnaire and the postoperative measurements are
minimal. Risks or adverse events of cataract surgery in this study are not
different from cataract surgery carried out outside this study. Possible
adverse events of the toric T2 intraocular lens do not differ from a standard
monofocal intraocular lens. An advantage for patients in this study is to
accomplish refinement of visual acuity. A disadvantage can be the extra time
investment.