Prevalence of Astigmatism

It has been proven that astigmatism is more prevalent than expected among cataract patients. High prevalence of corneal astigmatism has been reported in many research articles. After toric implantation, residual postoperative corneal astigmatism of 0.75 D or lower may improve uncorrected visual acuity and reduce symptomatic blur, ghosting of images, and halos.¹

40% of Cataract Patients Exhibit ≥1.0 D Astigmatism

The study published by Ferrer-Blasco T et al. in 2009, consisting of 4540 patients with cataract showed corneal astigmatism to be prevalent in 87% of patients.²

Another clinical study of 5987 cataract patients performed by Dr. Warren Hill, reported that 52.5% of patients had preoperative astigmatism of more than 0.75 D. The figure above shows the percentage of patients at various levels of preoperative Astigmatism.³

Clear Vision for Astigmatic Patients

You can make more patients happy. Patients will begin enjoyable life after surgery with clear vision and spectacle independence. AcrivaUD Toric has the largest diopter range in the astigmatism correcting IOLs which is defining as Custom Made Perfection. Spherical power starts from 0.00D to 32.00D and cylinder power range is available up to 10.00D with half diopter increments.

Best Solution is Plate Haptic

Larger incision causes itself surgically induced astigmatism and directly effects post-operative refractive outcomes. AcrivaUD Toric Plate haptic is the best choice platform enables implantation through sub 2.0 mm incision, it can minimize surgically induced astigmatism and stays in capsular bag without rotation.

Alignment of the AcrivaUD Toric lens in both side makes easier rotation during operation. It is always excellent rotational stability seen with plate haptic design as toric IOL hold on to posterior capsular bag in four points.

Plan Your Surgery

Preoperative Diagnosis

Amount and Axis of Astigmatism

Successful toric implantation starts with precise examination and evaluation of the amount and axis of corneal astigmatism. Selection of an ideal patient for toric application keratometry, biometry, pupillometry, aberrometry, videokeratoscopy or any other devices are recommended to use as a preoperative diagnostic evolution. Measurements should be repeated under suitable conditions if big differences are found among different methods. Determine the axis of astigmatism is equally important with its amount which involves directly outcomes after implantation. Regular astigmatism should be assured by checking topographic map of the cornea.

Inclusion Criteria

Optimum postoperative results are based on correct patient selection. Recommended inclusion criteria should be followed in a preoperative toric surgery plan. Total astigmatism of the eye is the value measured in routine clinical practice which includes both cornea-dependent external astigmatism and neutral lens-dependent internal astigmatism. Only external astigmatism must be taken into consideration in toric IOL calculation since the lens is removed during surgery. ⁵

Recent studies have shown the importance of considering the posterior corneal surface when determining total corneal astigmatism and planning astigmatism correction. The posterior cornea acts as a minus lens and it should be evaluated during pre-operative planning.^6,7

Acriva Easy Toric Calculator

Acriva^UD Easy Toric Calculator is developed to assist you easily planning your surgery and helping you reach precious toric outcomes.

You can access the Acriva^UD Easy Toric Calculator by visiting: https://easytoriccalculator.com/warning.php or you can download the application available for iPhone and iPad from the Apple Store and for all devices link to Android Market.

For more information AcrivaUD Easy Toric Calculator’s User Guide:

Marking The Eye

Preoperative Marking

Preoperative reference marking is recommended in the patient’s sitting position to limit cyclotorsional effect the eye exposed when switch from vertical to horizontal position. Mark a reference axis, ideally with the help of slit lamp, with a marking pen or ink pad. Slit lamp may also be used for targeted axis by changing lamp position to desired angle or axis marking may be done in conjunction with preop markers.

Intraoperative Marking

After changing patient sitting position to supine position, mark the targeted axis with fixation rings as Mendez with the guide of reference point. Pendulum markers is another option in which gravity allows the precious marking. Accurate axis marking is crucial in toric implantation as in case of rotational misalignment can be result of no cylindrical correction.

All Models:

References:

1- Nichamin LD., Astigmatism control. Opthalmol. Clin. North Am. 19, 485–493 (2006).

2- Ferrer-Blasco T. et al. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg 2009; 35:70-75.

3- Source: Warren Hill Keratometry database, Clinical study of 5987 US patients.

4-Data on le.

5-Ferreira TB, Marques EF, Rodrigues A, Montes-Mico R. Visual and optical outcomes of a diffractive multifocal toric intraocular lens. J Cataract Refract Surg. 2013;39(7):1029-35. 6- Visser N, Nuijts RM, de Vries NE, Bauer NJ. Visual outcomes and patient satisfaction after cataract surgery with toric multifocal intraocular lens implantation. J Cataract Refract Surg. 2011;37(11):2034-42.

7- Munoz G, Cardoner A, Albarran-Diego C, Ferrer-Blasco T, Belda-Salmeron L. Iris-xated toric phakic intraocular lens for myopic astigmatism. J Cataract Refract Surg. 2012;38(7):1166-75.