ASSORT® Website Calculators

ISRS members have access to the entire set of ASSORT® website calculators. These tools can help:

  • refractive surgeons improve astigmatism correction
  • cataract surgeons get astigmatism right with a high degree of accuracy
  • authors save time when publishing on astigmatism for the Journal of Refractive Surgery
  • regular clinicians refine their nomograms
  • any surgeon using a toric lens improve their accuracy

ASSORT Designer Cornea® Calculator
This ASSORT Designer Cornea Calculator is for investigational use. This enables investigations into potential treatment parameters for patients of surgical eye practices where this is in conjunction with excimer or femtosecond refractive laser device manufacturers.

ASSORT Ocular Residual Astigmatism Calculator
Use this tool for vectorial calculation of the difference between corneal astigmatism and refractive cylinder at the corneal plane preoperatively. Expressed in diopters and axis. Greater than 0.75D of ORA preoperatively leaves excess corneal astigmatism postoperatively if treated using refractive parameters alone. The method of Vector Planning is the best option to optimally treat astigmatism.

ASSORT Vector Planning® Calculator
This calculator incorporates corneal parameters into the refractive treatment plan to optimally treat astigmatism and minimize postoperative corneal astigmatism without increasing the refractive cylinder.

ASSORT Group Analysis Calculator
The ASSORT Group Analysis Calculator provides unlimited astigmatism analysis using the Alpins Method. This program, made available to ISRS members, can greatly facilitate your submissions to the Journal of Refractive Surgery with the ability to import data and export the appropriate vectorial analyses in both numerical and graphical reports.

ASSORT Toric IOL Calculator
With the ASSORT Toric IOL Calculator, plan for the most accurate toric IOL using personalized constants for calculation of effective lens position, flattening effect of the phaco incision, total corneal astigmatism and long eye adjustment.

ASSORT Toric IOL Refractive Surprise Calculator
The ASSORT Toric IOL Refractive Surprise Calculator calculates the optimal axis for the toricity of the implanted IOL to minimize post refractive cylinder. It uses the Alpins Method to determine if the IOL needs to be rotated, exchanged or corrected using LASIK. The Alpins Method vectorial analysis provides the angle of rotation to optimize the position of the implant where an improvement is possible in the refractive outcome by implant realignment. Note that also presented with the analysis is the Magnitude of Error (ME) which is calculated to determine if the implant toricity is accurate or is over or under powered.

ASSORT SIA and Flattening Effect of Incisions Group Analysis Calculator
This tool performs single and group astigmatic analyses for cataract incisional treatments. Two main astigmatic measures are analyzed, which can be grouped by incision meridian position: flattening/steepening effect and torque effect. The traditional surgically induced astigmatism vector (SIA) is also analyzed into its component parts at any meridian on the eye.

ASSORT Femto-LRI Calculator
This calculator provides the surgeon with the ability to accurately plan incisions to correct for corneal astigmatism using a selection of established nomograms, which include NAPA and Donnenfeld. With an easy to use graphical interface, the length of the incisions are displayed at the meridian entered by the user, together with the targeted post op corneal astigmatism. Additionally, the Femto-LRI calculator offers the surgeon the ability to perform vectorial outcome analyses with graphical display using the Alpins Method, allowing nomograms to be refined and applied to future procedures.

ASSORT Vector Calculator
The Vector Calculator: 1) enables calculations of the sum or difference between two astigmatisms or vectors; 2) displays these calculations on a double angle vector diagram and the corresponding polar diagram as it would appear on an eye.

ASSORT Coupling Calculator
This tool: calculates the coupling effect on sphere by myopic and hyperopic astigmatic treatments; is applicable to both incisional and ablative procedures; deals effectively with “off axis” SIA; and intuitively displays for coupling ratio, coupling constant and coupling adjustment.


Watch the video tutorial.


By using these calculators you agree to the terms and conditions of using these applications.