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To achieve a surgical-grade tomography, you will need to perform two acquisitions, which will be automatically processed providing a differential analysis to certify an accuracy exceeding 3 microns.
The second acquisition is needed to validate the exam by means of a repeatability analysis.
If the repeatability check is not satisfied a further set of two acquisitions will be required.

An examination with Precisio requires around 1 second to acquire 60 Scheimpflug cross-sections using a tandem camera system to triangulate the cornea shape and to track the eye movements.
Over 120,000 per each detected surface are processed in about 20 seconds per each one performed acquisition.

pMetrics™ exam is performed weighting, according to patient’s lifestyle, 6 different light conditions to define the Ideal Pupil™

  • Low brightness (Dark-Chamber) (Scotopic condition)
  • Average brightness (Artificial Light – Close Space)
  • Direct light in dark environment (Night Driving simulation)
  • High brightness (Day Light – Close Space)
  • Low brightness (Artificial Light – Open Space)
  • High brightness (Day Light – Open Space) (Fotopic condition)

The Ideal Pupil statistically defines the diameter which encompasses 95% (2 SD) of the typical conditions a patient encounters during his waking hours, in order to minimize tissue removal in refractive corneal surgeries and to provide assurance of pupil coverage with statistically appropriate dimension.

Customized ablations based only on refractive data deduced by Wavefront devices attempt to directly compensate the refractive errors under the assumption that there is no need to know the corneal morphology: Wavefront ablation profiles are based on a lens to be applied on the cornea with no consideration of the corneal morphology.
cTen™ regularizes the anterior surface of the cornea by identifying and delivering the ideal surface removing only the limited portion of tissue included between the anterior corneal profile and the ideal surface.
cTen™ requires less tissue ablation as the irregularities of the cornea increase, as opposed to Wavefront-guided ablations which require a higher amount of tissue as irregularities increase.

cTen™, performing a superficial ablation, preserves the monolithic structure of the cornea, while (femto)LASIK and SMILE techniques, due to the intrastromal cut, relevantly and permanently weaken the corneal structure of a factor higher than 1.5, depending from corneal biomechanical parameters.
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A healthy cornea may tolerate such a weakening induced by the intrastromal cut, but, if it occurs in presence of a local weakening of the corneal structure, it may induce a corneal ectasia.

CF/A™ is an iVis Technologies patented innovation, which continuously tunes the pulse delivery frequency of the iRes™ excimer laser to grant the delivery of a constant fluence per unit of time throughout the execution of the entire ablation profile.

Legacy laser systems attempt to compensate the unpredictability of the ablation rate induced by plume effects by adding additional pulses or through complex aspiration systems. For this reason, the Surgeons often are forced to devise and maintain complex nomograms. This unpredictability further grows with complex and irregular custom ablation shapes. Effective delivery of constant pulse rate per area significantly improves the precision of energy delivery and minimizes thermal effects.

Thanks to iVerify™ technology, which closes the loop of the surgical process, the surgical outcomes are objectively and statistically analyzed to automatically provide, when needed, a fine tuning of energy delivering and radial efficiency, thus avoiding the need of any kind of nomograms.

iVerify™ is the unique close loop, real time, web-based proprietary software, which allows a transparent and fully detailed statistical analysis, based on AI principles, of the iVis Suite™ surgical outcomes on a worldwide basis.

iVerify™ certifies full surgical process reliability, starting from pre-op examination, till post-op verification, scheduled at any desired time, analysing safety and efficacy parameters, according to the most relevant international standard.