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Precision tools for refractive surgery.

Interactive calculators, nomogram builders, simulators and informed-consent tools — developed by a surgeon and refined in daily clinical practice.

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Dr. med. Harald C. Gäckle
All apps by Dr. Harald C. Gäckle

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Fundamentals

Start here.

Refractive Surgery Do's and Don'ts

An interactive introduction to the essential rules of refractive surgery — what to do, what to avoid, and why. The ideal starting point before diving into the planning tools.

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Corneal Refractive Planning

LASIK, SMILE & CLEAR.

Residual Stromal Bed Calculator

Instant residual stromal bed calculation for LASIK, SMILE and surface ablation — from pachymetry, flap or cap thickness and ablation depth, with immediate safety margin assessment.

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Tissue-Saving Ablation Model for Hyperopic Astigmatism

This app addresses hyperopic LASIK ablation profiles with astigmatism. Some manufacturers offer a tissue-saving mode — here you can simulate it and compare the ablation profiles of different laser manufacturers.

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The Cap–Residual-Stroma Trade-off in CLEAR / SMILE

Explore how cap thickness and lenticule geometry interact with residual stromal thickness in lenticule extraction — an interactive look at the biomechanical safety envelope.

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CLEAR Nomogram

Treatment refinement for CLEAR lenticule extraction — nomogram-based adjustment of spherical and cylindrical corrections for improved refractive accuracy.

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FemtoLASIK

Flap planning.

Ideal Hinge Position Maker

Have you ever wondered where exactly to place the hinge in femto-LASIK to avoid lasering onto the hinge? This tool gives you a clear visual answer: just enter the steep axis, and it shows the ideal hinge position in an easy and intuitive way. Simple. Visual. Practical.

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Suction Ring Size Calculator

Selecting the correct suction ring size for femtosecond laser docking in FemtoLASIK and CLEAR — matching ring size to corneal geometry for optimal applanation and centration.

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Astigmatism Management

Incisional planning.

Castrop Nomogram for LRI

Limbal relaxing incision planning based on the Castrop nomogram — arc length, placement and depth for femtosecond laser–assisted astigmatism correction.

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New Arc Length Calculator

Calculates the shortening or lengthening of the LRI arc length induced by a clear corneal incision — based on incision width and axis.

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IOL Adjustment & Residual Astigmatism with Incision Axis

Not every cataract patient with corneal astigmatism receives a toric IOL. But if we implant a non-toric IOL, I still want to control where the remaining astigmatism “lands” refractively.

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Cataract & IOL Surgery

Planning, documentation & counseling.

Z8 Capsulorhexis Planner

Capsulotomy centration planning for the femtosecond laser — vertex- versus pupil-centred strategies with Galilei G4 data and automated OCR extraction from device printouts.

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Toric IOL Axis Calculator

Toric IOL calculator with modern formulas — just scan your biometry, no typing of data. That's it.

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Cataract Surgery — Operative Report

Structured operative report generator for cataract surgery with IOL placement selector, complication documentation and digital signature capture.

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Post-LASIK / PRK IOL Delta Calculator

My own post-LASIK “Pocket IOL Calculator” — deliberately pragmatic: a quick tool for everyday practice, for fast assessments or as a cross-check alongside established calculators like EVO 2.0, Haigis-L or Barrett True-K “No History”.

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Special IOL Communication Trainer

Scenario-based training for counselling patients on premium and special IOLs — realistic dialogue situations with structured feedback for surgeons and clinic staff.

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Nomogram Builders

Learn from your own outcomes.

Eagle Eye Refractive Laser Nomogram Builder

Generate surgeon-specific laser nomograms from your own outcome data — systematic, data-driven adjustment of sphere and cylinder for your platform and technique.

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Eagle Eye IOL Outcome Nomogram Builder

Build a personalised IOL outcome nomogram from your postoperative refractive results — refining constants and sharpening predictive accuracy over time.

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Patient Counseling & Simulation

Seeing what the patient will see.

Decision Helper

Guided decision support for patients weighing their vision correction options — comparing laser surgery, lenticule extraction, phakic IOLs and lens exchange based on individual parameters.

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Glare & Halo Simulator

Realistic night-vision simulation of glare and halos — setting accurate patient expectations before refractive surgery or premium IOL implantation.

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ICL Light Ring Simulator

Interactive simulation of the light ring phenomenon after ICL implantation — helping patients understand and anticipate this optical side effect before surgery.

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Vision Correction Cost Calculator – Surgery Financing Calculator

Patient-facing lifetime cost comparison of glasses and contact lenses versus refractive surgery — showing the long-term economics of vision correction.

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