Abbott Releases TECNIS Toric Calculator With Posterior Corneal Astigmatism Compensation
Abbott received FDA approval of a new Toric Calculator with Posterior Corneal Astigmatism (PCA) compensation. The addition of PCA compensation eliminates the need for look-up tables and improves the predictability of residual astigmatism.
Clinical studies found that PCA adds an average of 0.3 D to total corneal astigmatism.[1] Not accounting for PCA in calculating the required toric lens needed to correct an individual’s astigmatism may result in over-correction of with-the-rule astigmatism, under-correction of against-the-rule astigmatism and decreased patient satisfaction.
“By incorporating posterior corneal power and an exact vergence calculation for both toric and spherical IOL power, the new TECNIS Toric IOL calculator elegantly and comprehensively addresses posterior corneal astigmatism and potential inaccuracies," Douglas D. Koch, MD, Houston, TX.
Dr. Koch, a leading researcher, and expert on PCA, helped develop the Abbott PCA Algorithm for use in the Abbott Toric Calculator.
The Abbott Toric Calculator with PCA compensation is optimized for use with the TECNIS® family of Toric IOLs, including the recently released TECNIS Symfony® Toric Extended Range of Vision IOL. There was a 0.01 D prediction error shown when utilizing the Abbott PCA algorithm.[2]
“This new toric calculator demonstrates Abbott’s commitment to providing eye surgeons with a full complement of tools and resources for astigmatism management. When used in conjunction with the TECNIS® family of IOLs, it provides a new standard of care for addressing astigmatism,” said David Tanzer, MD, Chief Medical Officer for Abbott’s vision business.
INDICATIONS AND IMPORTANT SAFETY INFORMATION FOR TECNIS SYMFONY TORIC EXTENDED RANGE OF VISION IOLs
CAUTION: Federal law restricts this device to sale, distribution and use by or on the order of a physician.
INDICATIONS FOR USE: The TECNIS Symfony Toric Extended Range of Vision IOLs, Models ZXT150, ZXT225, ZXT300, and ZXT375, are indicated for primary implantation for the visual correction of aphakia and for reduction of residual refractive astigmatism in adult patients with greater than or equal to 1 diopter of preoperative corneal astigmatism, in whom a cataractous lens has been removed. The lens mitigates the effects of presbyopia by providing an extended depth of focus. Compared to an aspheric monofocal IOL, the lens provides improved intermediate and near visual acuity, while maintaining comparable distance visual acuity. The Model Series ZXT IOLs are intended for capsular bag placement only.
CONTRAINDICATIONS: None.
RISKS: Routine cataract surgery risks, irrelevant to lens selection, could be minor, temporary, or affect patients’ vision permanently. Rare complications are worsening of vision, bleeding, or infection. Risks related to use of this lens include a slight loss in vision sharpness with decreased use of glasses. Even with glasses, loss of sharpness may worsen under poor visibility conditions such as dim light or fog. This may lead to driving difficulties, and not detecting road hazards as quickly at night or in fog. Patients may also notice halos, starbursts, glare, and other visual symptoms with extended range of vision IOLs. This may impact patients when there are bright lights at night. Patients should discuss all risks and benefits with their eye doctor before surgery.
WARNINGS: A small number of patients may want their Tecnis Symfony IOL removed because of lens-related optical/visual symptoms. Patients with pre-existing diseases or conditions (i.e., diabetes and heart disease) may have higher risk of experiencing complications (e.g., more difficult recovery) after routine cataract surgery. Patients should not receive this lens if they have had previous trauma to their eye. Not evaluated for use in children.
PRECAUTIONS: If the patient’s eye is unhealthy (including glaucoma), vision may not be good even after cataract removal; patients may not get full benefit of the Tecnis Symfony IOL. Before surgery, the eye doctor will check for any eye diseases. Patients’ vision with the IOL may not be good enough to perform detailed ‘up-close’ work without glasses, and rarely, may make some types of retinal treatment (e.g., retinal tear repair) more difficult. Patients should take all prescribed medicines and apply eye drops as instructed to avoid inflammation and infection. Patients should avoid bending down and playing sports, which can harm the eye during recovery. The eye doctor will tell patients what activities to avoid.
The PCA is based on an algorithm that combines published literature (Koch et.al, 2012) and a retrospective analysis of data from a TECNIS Toric multi-center clinical study. The PCA algorithm for the selection of appropriate cylinder power and axis of implantation was not assessed in a prospective clinical study and may yield results different from those in the TECNIS Toric intraocular lens labeling. Please refer to the AMO Toric Calculator user manual for more information. Variability in any preoperative measurements can influence outcomes.
ATTENTION
Reference the Directions for Use for a complete listing of Indications and Important Safety Information.
PP2016CT1311
[1] 1Koch DD et al. Contribution of posterior corneal astigmatism to total corneal astigmatism. J Cataract Refract Surg. 2012 Dec;38(12):2080-7
[2] Canovas, et al., ASCRS 2016 Presentation_Impact of Posterior Corneal Astigmatism in Toric IOL Power Calculations