Astigmatism and cataract: understanding the toric implant

Astigmatism affects nearly one third of the adult population and is frequently found alongside a cataract from the age of 60. The toric implant makes it possible to correct both the clouding of the lens and corneal astigmatism at the same time, in a single procedure and with greater independence from distance glasses.

Contents

Astigmatisme et correction par implant torique Deux vignettes côte à côte. À gauche, une cornée ovalisée aux deux courbures différentes dédouble l'image. À droite, un implant torique, en teal, aligné sur le bon axe rétablit une image nette. Une flèche centrale indique la correction. Astigmatisme et implant torique Cornée ovalisée deux courbures E E image dédoublée correction Implant torique axe aligné E image nette

UNDERSTANDING

Understanding pre-cataract astigmatism

Astigmatism is caused by an asymmetrical corneal curvature: the cornea takes on the shape of a rugby ball rather than a football. This asymmetry distorts the image transmitted to the retina, whatever the distance. Around 30 to 40% of the adult population has astigmatism greater than 0.75 diopter, which is clinically significant.

During standard cataract surgery with a non-toric monofocal implant, any pre-existing astigmatism persists after the operation. According to Al-Mohtaseb et al. (Ophthalmology, 2024, AAO report), implanting a toric lens during surgery allows for a predictable reduction of residual astigmatism and a significant improvement in uncorrected distance vision.

WHO IS CONCERNED

Who is concerned?

The toric implant is offered to patients undergoing cataract surgery who present with:

  • Regular corneal astigmatism ≥ 1.0 diopter (some studies use ≥ 0.75 D)
  • A wish to reduce dependence on glasses for distance vision
  • Stable keratometry, without progressive keratoconus
  • No active corneal disease (pemphigoid, severe uncontrolled dryness)

In patients who have already undergone corneal refractive surgery (prior LASIK, PRK), the toric implant remains an option, but the biometric calculations are more complex — Pellegrini et al. (JCRS, 2022) detail the adjustments required in these post-keratorefractive situations.

SOLUTIONS

The solutions: the toric implant

The toric implant is an aspheric intraocular lens incorporating a cylindrical correction. It is custom-made according to the patient’s biometry (IOL Master, Lenstar) and corneal topography. Peripheral markings allow precise alignment along the axis of the corneal astigmatism.

Current ranges cover up to 6 diopters of corneal astigmatism, in steps of 0.75 to 1.50 diopters. Some implants combine toric and multifocal correction (toric trifocal or toric EDOF), making it possible to treat astigmatism, presbyopia and cataract at the same time.

Intraoperative alignment is critical: a 10° rotation after placement leads to a loss of roughly one third of the cylindrical effect. Digital guidance systems (such as Verion or Callisto) improve alignment accuracy. A residual rotation > 10° affects 1 to 3% of patients and may require a simple surgical repositioning in the weeks following the operation.

For more information, see the page dedicated to cataract surgery and to the toric implant.

PATHWAY

The treatment pathway

The preoperative assessment for a toric implant is more thorough than for a simple cataract: optical biometry with keratometric measurement, corneal topography (anterior and posterior surface), and possibly anterior-segment OCT. These examinations determine the spherical and cylindrical power of the implant, as well as its placement axis.

Dr Tourabaly consults in Cachan (94) and in Paris 13 for the initial assessment. The procedure is carried out at the Clinique Sainte-Geneviève (Paris 14). A check-up at day 1 and then at 1 month allows the positioning and cylindrical result to be verified. Appointments: 01 45 47 08 11 or Doctolib.

Dr Tourabaly’s perspective

“Many patients with significant astigmatism have lived their whole lives with a visual discomfort they considered unavoidable. When a cataract develops, it is an opportunity to incorporate a toric implant in the same procedure. The renewed visual comfort at distance, without glasses, is often a discovery for them. It remains essential to carefully assess the regularity of the cornea before any decision.”

FAQ

Frequently asked questions

A toric implant is an intraocular lens that includes a cylindrical correction to compensate for corneal astigmatism. Custom-made and precisely aligned along the astigmatism axis during the procedure, it corrects the cataract and the astigmatism at the same time.

A toric implant is generally offered from a regular corneal astigmatism of 1.0 diopter, sometimes from 0.75 D depending on the biometric data. Beyond 6 diopters of corneal astigmatism, other approaches may be discussed (associated relaxing incisions, complementary LASIK).

The surgical procedure is reimbursed by the French national health insurance (Sécurité sociale) as cataract surgery. The toric implant is subject to an additional fee (around €300 to €800 per eye) that is not reimbursed, and is partly covered by some complementary insurers offering a premium-implant package.

A residual rotation is possible in the first few days in 1 to 3% of patients. Beyond 10° of rotation, a simple surgical repositioning can be offered within 1 to 2 months. After that, capsular fibrosis stabilizes the implant and its axis no longer varies.

Yes. Toric trifocal and toric EDOF implants exist, making it possible to correct the cataract, the astigmatism and presbyopia at the same time. This combined choice requires precise biometric assessment and a thorough preoperative discussion of expectations and limitations.

Cataract and astigmatism assessment with Dr Tourabaly

Book an appointment on Doctolib
Learn more — cataract surgery

Sources

  1. Al-Mohtaseb Z, Steigleman WA, Pantanelli SM, et al. Toric Monofocal Intraocular Lenses for the Correction of Astigmatism during Cataract Surgery: A Report by the American Academy of Ophthalmology. Ophthalmology. 2024;131(5):587-595. PMID 38149945
  2. Pellegrini M, Furiosi L, Yu AC, et al. Outcomes of cataract surgery with toric intraocular lens implantation after keratorefractive surgery. J Cataract Refract Surg. 2022;48(5):587-593. PMID 34174044

This article is for informational purposes. A personalized ophthalmological opinion remains essential for any therapeutic decision.

Written and reviewed by Dr Moïse Tourabaly, ophthalmic refractive surgeon — former chief resident (Quinze-Vingts National Eye Hospital).

Last updated: July 6, 2026

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