Step 2: Surgical Planning for Toric IOL Implantation



The process for selecting the correct toric IOL is twofold:
1) Determine the required spherical lens power by using the preferred method and formula as with conventional IOLs and
2) Determine the magnitude, orientation and type of preexisting corneal astigmatism through keratometry and topography. Once you have captured the patient’s data, the toric calculator will help you determine the surgical plan and select the appropriate lens.

Any cataract surgeon can incorporate a toric lens into his or her practice easily. Besides maybe a toric marker set, all the tools the surgeon needs, he or she already has in the office."

Bonnie Henderson, MD*
Ophthalmic Consultants of Boston

*Dr. Henderson is a paid consultant for Alcon.

Accounting for Surgically Induced Astigmatism in Toric IOL Procedures

Any incision on the cornea will modify its refractive power by lessening the power in the steep meridian and increasing it in the flat meridian. This is the case whether the incision is placed on the meridian or anywhere else. Like A-constants, you should assess your individual results, and determine a personalized induced astigmatism number, based on the results you have historically produced. By knowing your SIA you can account for it in your surgical planning and achieve optimal patient outcomes.

How do I determine my SIA?

To find your SIA, you can track a number of your cases to better determine the amount of SIA you should account for. Tools such as Dr. Warren Hill’s SIA Calculator can help you track your individual SIA.

Default SIA values

If you’re just starting out with toric IOLs, use the following default SIA measurements1:

  • 0.5 D if your incision is 2.5 mm or smaller
  • 0.75 D if your incision is 2.6–2.75 mm

Note that SIA can change based on the location, size, angle and type of incision. SIA also tends to be reduced with smaller incisions.2

Test Your Knowledge

Are you ready to take keratometry measurements and use patient data in the toric calculator?

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View Important Product Information for
AcrySof® IQ Toric IOL+

ACRYSOF® IQ TORIC INTRAOCULAR LENSES IMPORTANT PRODUCT INFORMATION

CAUTION: Federal (USA) law restricts this device to the sale by or on the order of a physician.

INDICATIONS: The AcrySof® IQ Toric posterior chamber intraocular lenses are intended for primary implantation in the capsular bag of the eye for visual correction of aphakia and pre-existing corneal astigmatism secondary to removal of a cataractous lens in adult patients with or without presbyopia, who desire improved uncorrected distance vision, reduction of residual refractive cylinder and increased spectacle independence for distance vision.

WARNINGS/PRECAUTIONS: Careful preoperative evaluation and sound clinical judgment should be used by the surgeon to decide the risk/benefit ratio before implanting a lens in a patient with any of the conditions described in the Directions for Use labeling. Toric IOLs should not be implanted if the posterior capsule is ruptured, if the zonules are damaged, or if a primary posterior capsulotomy is planned. Rotation can reduce astigmatic correction; if necessary lens repositioning should occur as early as possible prior to lens encapsulation. All viscoelastics should be removed from both the anterior and posterior sides of the lens; residual viscoelastics may allow the lens to rotate.

Optical theory suggests that high astigmatic patients (i.e., > 2.5 D) may experience spatial distortions. Possible toric IOL related factors may include residual cylindrical error or axis misalignments. Prior to surgery, physicians should provide prospective patients with a copy of the Patient Information Brochure available from Alcon for this product informing them of possible risks and benefits associated with the AcrySof® IQ Toric Cylinder Power IOLs.

Studies have shown that color vision discrimination is not adversely affected in individuals with the AcrySof® Natural IOL and normal color vision. The effect on vision of the AcrySof® Natural IOL in subjects with hereditary color vision defects and acquired color vision defects secondary to ocular disease (e.g., glaucoma, diabetic retinopathy, chronic uveitis, and other retinal or optic nerve diseases) has not been studied. Do not resterilize; do not store over 45° C; use only sterile irrigating solutions such as BSS® or BSS PLUS® Sterile Intraocular Irrigating Solutions.

ATTENTION: Reference the Directions for Use labeling for a complete listing of indications, warnings and precautions.

Click here to view the AcrySof® IQ Toric IOL Directions for Use (DFU).

ACRYSOF® IQ TORIC INTRAOCULAR LENSES IMPORTANT PRODUCT INFORMATION

CAUTION: Federal (USA) law restricts this device to the sale by or on the order of a physician.

INDICATIONS: The AcrySof® IQ Toric posterior chamber intraocular lenses are intended for primary implantation in the capsular bag of the eye for visual correction of aphakia and pre-existing corneal astigmatism secondary to removal of a cataractous lens in adult patients with or without presbyopia, who desire improved uncorrected distance vision, reduction of residual refractive cylinder and increased spectacle independence for distance vision.

WARNINGS/PRECAUTIONS: Careful preoperative evaluation and sound clinical judgment should be used by the surgeon to decide the risk/benefit ratio before implanting a lens in a patient with any of the conditions described in the Directions for Use labeling. Toric IOLs should not be implanted if the posterior capsule is ruptured, if the zonules are damaged, or if a primary posterior capsulotomy is planned. Rotation can reduce astigmatic correction; if necessary lens repositioning should occur as early as possible prior to lens encapsulation. All viscoelastics should be removed from both the anterior and posterior sides of the lens; residual viscoelastics may allow the lens to rotate.

Optical theory suggests that high astigmatic patients (i.e., > 2.5 D) may experience spatial distortions. Possible toric IOL related factors may include residual cylindrical error or axis misalignments. Prior to surgery, physicians should provide prospective patients with a copy of the Patient Information Brochure available from Alcon for this product informing them of possible risks and benefits associated with the AcrySof® IQ Toric Cylinder Power IOLs.

Studies have shown that color vision discrimination is not adversely affected in individuals with the AcrySof® Natural IOL and normal color vision. The effect on vision of the AcrySof® Natural IOL in subjects with hereditary color vision defects and acquired color vision defects secondary to ocular disease (e.g., glaucoma, diabetic retinopathy, chronic uveitis, and other retinal or optic nerve diseases) has not been studied. Do not resterilize; do not store over 45° C; use only sterile irrigating solutions such as BSS® or BSS PLUS® Sterile Intraocular Irrigating Solutions.

ATTENTION: Reference the Directions for Use labeling for a complete listing of indications, warnings and precautions.

Click here to view the AcrySof® IQ Toric IOL Directions for Use (DFU).