Outils – Pr. Damien Gatinel

Zernike Synthesizer — Wavefront sonification

Tue, 09 Jun 2026 11:58:36 +0000

This experimental instrument converts Zernike polynomial coefficients into sound, offering an unprecedented way to listen to wavefront optics. Each of the 28 modes (up to the 6th radial order) drives an oscillator whose waveform is derived from the phase map evaluated over the pupil. Patterns that look similar on the phase map can sound very different, while seemingly unrelated aberrations reveal unexpected harmonic relationships: this is not a diagnostic tool, but a different, sensory perception.

Key features

28 Zernike modes (up to the 6th order) as real-time audio oscillators
4 synthesis engines: additive, waveshaper, FM and spiral pupil sweep
Zernike pyramid with phase-map previews and a 28-channel mixer
Stereo separation: sine-symmetric modes (m < 0) on the left, cosine-symmetric (m > 0) on the right
8 clinical presets (keratoconus, astigmatism, spherical aberration…) and 8 animated sequences
4-voice polyphony, audio/video recording and a bilingual interface (French/English)

Corneal asphericity impact analyser

Tue, 09 Jun 2026 11:58:34 +0000

This tool lets you study how variations in corneal asphericity (Q factor) influence spherical aberration (Z4,0), the vergence distribution and the depth of field. Through interactive 3D visualisations and real-time computations, it connects theoretical optics to clinical practice by showing the link between corneal shape and visual quality. It is particularly useful for presbyopia-correction procedures and for choosing an aspheric IOL.

Key features

Interactive manipulation of the Q factor with real-time spherical-aberration analysis
Vergence mapping (radial and Laplacian) to assess the induced multifocality
Through-focus MTF analysis and depth-of-field optimisation
PSF visualisation and convolved-letter simulation
Conversion between the corneal plane and the spectacle plane
Inclusion of the eye’s native spherical aberration in the model

Wavefront-to-radial-vergence power map converter

Damien Gatinel, MD, PhD — Tue, 09 Jun 2026 11:58:34 +0000

This tool bridges wavefront analysis and clinical refraction. It converts Zernike polynomial coefficients expressed in microns into refractive power maps expressed in dioptres. Instead of displaying the optical path difference like a conventional aberrometer, it generates radial-vergence maps that directly reveal the myopic and hyperopic zones across the whole pupil surface, making correlation with the manifest refraction easier.

Key features

Algorithms converting Zernike coefficients into dioptres
Radial-vergence power mapping
Identification of the myopic and hyperopic zones of the pupil
Direct correlation with the measured clinical refraction
Visualisation of the refractive impact of higher-order aberrations on vision

Combined astigmatism calculator & visualiser

Tue, 09 Jun 2026 11:58:34 +0000

This vectorial-analysis tool combines several astigmatism components — corneal, lenticular and residual — to derive the power and axis of the resulting cylinder. It provides both a numerical result and a graphical representation, which makes toric-IOL planning and cross-cylinder calculations easier. The often tricky operations of combining oblique cylinders are thus simplified while keeping rigorous mathematical accuracy.

Key features

Vectorial addition and subtraction of cylinders
Combination of corneal, lenticular and residual astigmatism
Assistance with toric-IOL planning
Handling of crossed and oblique cylinders
Double-angle plot representation
2D and 3D vectorial visualisation and sinusoidal modelling

Universal IOL Formula Analyser & Optimiser

Tue, 09 Jun 2026 11:58:33 +0000

This tool lets cataract surgeons import their own surgical-outcome data (CSV or Excel) to assess the performance of any IOL power formula and optimise its constants. The statistical analysis is produced within seconds: automatic detection of the relevant columns, normality tests, distribution analysis and publication-ready charts (histograms, box plots, violin plots, cumulative distribution functions, scatter plots with regression). The optimisation relies on the sensitivity-factor method (F = 0.0006(P² + 2KP)) and computes three targets simultaneously, while keeping patient data confidential since everything is processed in the browser.

Key features

Universal IOL-constant optimisation for any formula with a positional constant
Smart column detection, whatever the spreadsheet layout
Three simultaneous optimisation targets: zero mean error (ME=0), minimal standard deviation (SD-min) and minimal root-mean-square error (RMS-min)
Regression on several biometric parameters and subgroup analysis with comparison
Cumulative numeric filtering to target specific biometric populations
Seven languages, dark mode, responsive design; no installation, no data sent to an external server

PEARL-DGS: IOL power calculator

Tue, 09 Jun 2026 11:58:31 +0000

The PEARL-DGS formula, developed by Debellemanière, Gatinel and Saad and published open-source, computes IOL power by combining thick-lens equations with machine-learning models that predict the posterior corneal radius and the effective lens position (TILP). The tool offers three dedicated modules: « Regular Eyes » for standard cataracts (choice of keratometric index, biometer and IOL model), « Complex Eyes » for challenging cases (corneas after myopic or hyperopic LASIK/PRK, radial keratotomy, scarred corneas, eyes carrying an ICL) and « Second Eyes », which refines the second-eye prediction from the first-eye data. Optional parameters (lens thickness LT, central corneal thickness CCT, white-to-white WTW) further improve accuracy when available.

Key features

Machine-learning prediction of the lens position (TILP)
Algorithms suited to corneas after refractive surgery
Options for radial keratotomy and scarred corneas
Specific adjustments for eyes carrying an ICL
Second-eye optimisation from the first-eye data
Open-source methodology and online access (iolsolver.com)

IOL exchange power calculator

Tue, 09 Jun 2026 11:58:31 +0000

This tool estimates the power of the replacement IOL when a refractive surprise occurs after cataract surgery. It relies on a non-empirical vergence method, entirely independent of the usual IOL calculation formulas, using only the power of the IOL in place, the manifest refraction, the keratometry (K1/K2) and the cornea-to-IOL distance. For toric IOLs, it performs a full vectorial analysis and computes an optimal rotation angle presented as an alternative to exchange.

Key features

Non-empirical vergence calculation, independent of IOL formulas
Support for toric IOLs with vectorial analysis (J0/J45)
Posterior-cornea compensation (Koch, Abulafia-Koch, Goggin, LaHood)
Comparison between optimal rotation and IOL exchange
Q-ratio method (Gatinel) and sensitivity analysis
Multilingual interface and PDF export for clinical documentation

Optimal rotation calculator for toric IOLs

Tue, 09 Jun 2026 11:58:31 +0000

This interactive tool computes and illustrates the optimal rotation angle of a toric IOL to minimise residual astigmatism after surgery. It relies on a full vectorial analysis (J0/J45) and converts the toric power between the IOL plane and the corneal plane from the effective lens position (ELP). Designed as a decision-support and teaching aid, it is intended for cataract surgeons.

Key features

Optimisation of the angle θ to minimise residual cylinder and target the intended spherical equivalent
IOL-to-cornea toric conversion via the effective lens position (ELP)
Model based on the Gatinel Q-ratio and vergence
Frontal and surgical views of the IOL positioning
Associated optimisation curves and profiles
Vectorial representation of astigmatism (J0/J45 components)

Pupil transformation analyser for Zernike coefficients

Tue, 09 Jun 2026 11:58:29 +0000

Pupil diameter and centring vary with lighting, accommodation and measurement conditions, which directly alters the Zernike coefficients and the refraction. This tool exactly recomputes the wavefront coefficients (OSA/ANSI standard, up to the 8th radial order) for a new pupil geometry, through an analytical polynomial re-expansion without interpolation or approximation. It derives the objective refraction before and after transformation, and simulates the retinal image quality by PSF convolution to visualise the optical consequences of a pupil change.

Key features

Exact analytical transformation of Zernike coefficients (up to the 8th radial order)
Pupil-diameter reduction and arbitrary decentration (polar or Cartesian coordinates)
Objective refraction (sphere, cylinder, axis) for the initial and transformed wavefront
Wavefront visualisation with RMS comparison (initial vs transformed)
Retinal image simulation by PSF convolution (monochromatic and polychromatic)
Bilingual interface (French/English), standalone, no server required

Retinal image simulator from wavefront aberrations

Tue, 09 Jun 2026 11:58:29 +0000

This tool translates complex wavefront data into clinically usable information. From Zernike polynomial coefficients and higher-order aberrations, it reconstructs a visual image of the predicted retinal quality. By modelling the effect of aberrations on the point spread function (PSF) and the modulation transfer function (MTF), it helps explain the expected visual outcome to the patient and refine correction strategies.

Key features

Analysis of Zernike polynomials up to the 6th order
Visualisation of the PSF and the MTF
Comparative before / after treatment modelling
Adaptation to each patient’s own pupil size