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Concept: Toric lens


We present an overview of currently available toric intraocular lenses (IOLs) and multifocal toric IOLs. Relevant patient selection criteria, IOL calculation issues, and surgical techniques for IOL implantation are discussed. Clinical outcomes including uncorrected visual acuity, residual refractive astigmatism, and spectacle independency, which have been reported for both toric IOLs and multifocal toric IOLs, are reviewed. The incidence of misalignment, the most important complication of toric IOLs, is determined. Finally, future developments in the field of toric IOLs are discussed. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Concepts: Ophthalmology, Lens, Presbyopia, Contact lens, Refractive error, Intraocular lens, Cataract, Toric lens


We performed a systematic review and meta-analysis to evaluate the benefit and harms associated with implantation of toric intraocular lenses (IOLs) during cataract surgery. Outcomes were postoperative uncorrected distance visual acuity (UCDVA) and distance spectacle independence. Harms were evaluated as surgical complications and residual astigmatism.

Concepts: Medicine, Surgery, Visual acuity, Ophthalmology, Presbyopia, Intraocular lens, Cataract, Toric lens


To evaluate the optical performance of toric intraocular lenses (IOLs) after decentration and with different pupil diameters, but with the IOL astigmatic axis aligned.

Concepts: Presbyopia, Intraocular lens, Eye surgery, Toric lens


To compare the results between hydroimplantation of a single-piece, acrylic foldable toric intraocular lens (IOLs) and conventional implantation using an ophthalmic viscosurgical device (OVD).

Concepts: Lens, Intraocular lens, Toric lens, Aphakia


To compare precision in toric intraocular lens (TIOL) alignment and refractive outcomes between an intraoperative automated digital marker system and the conventional manual-ink marking.

Concepts: Lens, Intraocular lens, Toric lens, Alignment


To analyze the refractive predictability of low-power and medium-power toric intraocular lenses (IOL) during cataract surgery.

Concepts: Ophthalmology, Intraocular lens, Cataract, Toric lens, Lenses


We describe a surgical technique for the correction of isolated congenital lenticular coloboma associated with high corneal astigmatism. Transscleral fixation of the capsular bag with a single eyelet Cionni capsular tension ring was followed by in-the-bag implantation of a toric intraocular lens (IOL). This lead to complete correction of the lenticular defect and perfect alignment of the toric lens. In this case, the child attained an unaided distance visual acuity of 20/30 following amblyopia therapy and a well-aligned toric IOL at 12 months of follow-up. This technique can be used in cases with concomitant lenticular coloboma and significant corneal astigmatism.

Concepts: Eye, Visual acuity, Ophthalmology, Lens, Contact lens, Corrective lens, Intraocular lens, Toric lens


This study develops a method to determine toricity ratios used by arbitrary toric intraocular lens calculators. Access to this information allows for the improvement of refractive results. We derive the Sayegh-Gabra formula, which uses input and output parameters in a toric calculator to extract toricity ratios that are typically not disclosed. We illustrate the method on a number of commercial calculators. For each calculator, high, average, and low axial length values are crossed with high, average, and low mean corneal power values to generate a 3 × 3 matrix. A toricity ratio is generated for each axial length and mean corneal power pair. We thus identify several toric lens manufacturers' calculators that use a constant toricity ratio, often 1.46. Some others use a variable ratio centered at 1.46, but varying as axial length and mean K increases over a range of values corresponding to physiological myopia and hyperopia. There is an emerging trend away from constant toricity ratios. Using our methodology, it is possible to extract the toricity ratio used by specific calculators/manufacturers, distinguish those using constant versus variable toricity ratios, and use this information to improve surgical outcomes by refining current and future toric intraocular lens calculators.

Concepts: Cornea, Lens, Presbyopia, Contact lens, Corrective lens, Algebra, Intraocular lens, Toric lens


To compare the rotational stability of the 2 most commonly used toric intraocular lenses (TIOLs).

Concepts: Comparison, Comparisons, Intraocular lens, Toric lens, Lenses


To compare the accuracy of two common reference marking methods for toric intraocular lens alignment before and after using the novel toriCAM application.

Concepts: Novel, Intraocular lens, Toric lens