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.

Measuring Ks

Keratometry is the most important biometric measurement in preparing for a toric IOL procedure. It is used to determine corneal measurements, including corneal curvature and presence and orientation of the steep and flat meridians of astigmatism. Accurate Ks ensure proper IOL selection and toric alignment, resulting in the best possible postoperative outcomes.

Keratometry measurements

Keratometry tips

  • Use the same instrument in pre-op and post-op for each patient
  • Take measurements before applying anesthetic or dilating drops
  • Repeat your measurements for verification
  • Use the same measurement method across your practice
  • Designate the same tech to take K measurements
  • Make sure Ks are 90 degrees apart
  • Patients should stop wearing contact lenses at least two weeks prior to taking measurements


When to remeasure1

  • Readings are inconsistent between measurements.
  • Corneal power is less than 40.0 D or greater than 47.0 D.
  • Average corneal power differs by more than .09 D between eyes.
  • Astigmatism for either eye is greater than 2.50 D.
  • The corneal diameter (white to white) is less than 10.75 mm or greater than 13.0 mm.


Test Your Knowledge

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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).