How will laser treatment in the future look like?

Not much different. Bioshape does  not change the refractive laser surgery. It just adds  a measurement to it! 

The diagnoses stays like it is right now. Then before the treatment starts the cornea is measured. With this measurement it will be possible to verify the data that was measured during diagnoses when the tearfilm was still on. Then the flap is cut and usual treatment preparation is done. Before the actual treatment starts a second measurement of stroma bed serving as a reference is taken. During the treatment 5 - 10 single pulse measurements will be performed. According to this data the ablation algorithm can be fine tuned.
When the treatment is done the cornea will be measured before flap repositioning and after flap repositioning to have a final map with epithelium.

How does BioShape measure and what are the benefits to have a measurement?

Only a single excimer laser pulse is required for the measurement. A software controlled flip mirror is positioned into the conventional ray path. The measuring system is then imaging an uv light pattern onto the corneal tissue. Both, epithelium and stroma show fluorescence. This fluorescence image  is detected with a high resolution CCD camera. The data is evaluated on a Windows PC while the treatment continues. The result is a 3D elevation map that will guide the laser to an optimal result of the surgery.

exact initial correction
no over- or undercorrection
no decentration
avoids enhancements
safe procedure
accounts for corneal hydration
no hassle with nomograms
no more central islands
no treatment delay
wavefront compatible

When is the system available and is it also available for my existing laser?  I looked at your web site and I am confused about your product.  What can it do for me now when I use the Visx S2 to perform Lasik on patients?  I'm using the Chiron 217-C laser system.  Can I use it with this laser ?

The product is an add on for any refractive laser, already existing or new. It gives you a treatment control as it measures the amount of tissue taken off by the laser. Currently there is no online treatment control. The people who do the eye-surgery use Nomograms to fill that gap a little. But Nomograms are guidelines for laser settings based on specific treatment site conditions. They do not consider individual tissue properties. Online topometry is necessary because the laser only works with high precision on standardized material. Corneal tissue is not standardized as its humidity can change.

OK! But when can I get the online topometry for my laser?

As soon as we have an agreement with a laser company the system will be implemented into the laser. Some time after the clinical trials it will be available to any surgeon and existing systems can be upgraded. We are talking to all 9 laser producers worldwide and to some of the laser centers. 6 of these 10 companies would like to have an exclusive contract for the online topometry - even for a period of time. Depending on the brand of laser that you use, it could be possible that the online topometry is available end of this year or in a few years from now. We expect, that the refractive surgery market will push one of the laser producers into the contract because of the requests of there customers. You can decide it too by contacting your favorite laser producer or laser center.

Please understand that we want to work together with the most successful laser producer. We will go public and our existing investors and also our future investors - maybe you? - expect that we market our technology to our investors max. benefits. Thank you for your understanding.

What is the difference between the refractive surgery done right now and your technology?

The only difference is: With our technology we add an online measurement (a permanent measurement during the refractive surgery) to the existing process. Right now the topometry of your eye is measured before the surgery and then the refractive laser shapes your cornea according to that data. But nobody can measure how especially your cornea reacts on the laser pulses, so over- or undercorrections happen frequently. Our system measures online and guides the laser to an optimal result.

Is the EyeShape system a stand alone topography unit?

No. The EyeShape system is an add on for a refractive laser device containing an excimer laser or another UV laser source.

Which medical excimer laser is available that already has got the EyeShape system?

BioShape is currently in the process of negotiating with all medical laser companies. As a result of these negotiations we anticipate to deliver the first systems for end users in the year 2000.

What is the main principle of operation of the EyeShape system?

Measurements are based on a fluorescence pattern emitted by the most outer layer of the corneal tissue. This tissue layer serves as a light source rather than a mirror as in placido ring based systems. The pattern is observed with a CCD camera under an oblique angle to appear distorted. The amount of distortion is directly related to the height information.

How does the EyeShape system measure online during surgery?

Excimer laser pulses of very low intensity are guided through the EyeShape’s optical system during the ongoing surgery. The fluorescence pattern emitted by the tissue is detected and analyzed within a few seconds. The result is communicated to the software that controls the laser which in return adjusts the following pulses accordingly.

Does the EyeShape system work with both wide field lasers and flying spot lasers?

The EyeShape system only requires energies of less than 5 mJ as fluorescence is already emitted far below the ablation threshold. Thus it works well with both kinds of lasers.

Will the EyeShape system be available for existing lasers?

The EyeShape system is principally adaptable to any ophthalmic ArF excimer laser as only the wavelength of the laser pulses is required. Developments for existing lasers are included in the negotiations with the laser companies.

How many data points does the EyeShape system actually use?

The gray value of every camera pixel is used for the evaluation. Currently the camera has 1 megapixels.

Which height resolution is anticipated?

As the surrounding gray values of each pixel also contribute to the evaluation a height resolution of 1/5 of the lateral dimension of a pixel is reasonable. A field of view of 10 x 10 mm yields a resolution of approximately 2 microns.

Is it possible to become an investigator for the new technology?

Please contact your favorite refractive laser supplier and ask them. We can help you to get in touch with the right people there but we will not decide the who and when!

Is it possible buy shares of BioShape AG?

No. Its not possible yet. The BioShape AG will go public in approx. 3 years and will then be ready for public stockholders. Don´t miss to subscribe our mailing list to be updated frequently!

I am from the US or Canada: Will there be an office in the US in the near future for service, spare parts and support?

Yes! We are under the schedule to establish an assembly/service facility in the USA around fall 99.

Is the system already available in Europe? What is the price?

The system will be available all over the world depending on the laser company. The price will be set by the laser company as they will supply the system to you.

What happens if there is fluid accumulation on the surface of the cornea during the ablation process? Is the measuring radiation blocked?

Fluid accumulation mainly occurs with low fluence of the laser as the fluid is not evaporated by the pulse together with the tissue. Depending on the thickness of the liquid layer on the surface we propose to wipe away the fluid using a hockey knife or some sort of a sponge. This is a procedure which is also recommended during the treatment by some manufacturers. The treatment would have to be interrupted for a few seconds for the measurement anyway so this does not cause any additional trouble.

The dynamic hydration state of the cornea is associated with a change in thickness. Swelling might occur as well as thinning. How can you account for these effects?

As our method provides surface data it will always measure the actual topology independent of the hydration state. According to a publication of Boehnke et al. (J. refr. surg. 14, 1998, p.140) the decrease in thickness of the stoma exposed to ambient conditions is below 5 microns / minute. As the whole operation will only take about one minute this factor is in the order of our measuring accuracy. The conditions during surgery usually result in higher hydration. Thus swelling might play a role. This effect has to be accounted for via a calibration. Again we would propose to wipe away expressed fluid.

How do you cope with saccadic movements of the eye?

We use one excimer laser pulse for each measurement which lasts for some tens of nanoseconds. The registered fluorescence has a lifetime which is only slightly longer. Motion artefacts during one measurement can thus be excluded.

How can you compensate for movements between the measurements?

The measurements will be aligned with respect to each other. This topic is currently under investigation. Either the eyetracker of the laser or the topometry system itself aiming at specific marks (e.g. the boundary of the ablation zone) will provide the required data to do the alignment.

Do you have any data that shows that your technology improves results? As a refractive surgeon, I would love to see it.

There have been no clinical trials yet. As soon as one of the manufacturers incorporates our system these data will be available quickly. We anticipate a large improvement of the results as up to now nobody knows how much tissue is really being taken off by the laser.

For more questions, do not hesitate to send us an Email! Please help us to help you. We would really like to have the best FAQ-page on the web.

In your downloads section for surgery result, you have an example of an astigmatism ablation performed off axis. What is your methodology for determining the proper alignment axis is during the ablation?

In the example we compared an intended astigmatic treatment with its execution. We do not know the reason why the intended axis does not correspond to the treated axis. Maybe the patients eye rotated before our final measurement. At that time our sensor had not been incorporated in the laser. Instead we moved the sensor automatically over the patient's eye. In the future this eye rotation should not occur as our machine is already in the laser. Another reason might have been a wrong treatment axis being entered into the laser. This would have resulted in the same finding. We principally believe it will be best to mark the eye when diagnosing the axis and to relocate the mark when the patient is under the laser. With our instrument you might as well make a topography before the treatment starts to find out whether the eye rotated.

There were examples of decentered ablations in your downloads.There are two main elements in centration of an ablation. First is proper centration over the intended treatment zone by a well functioning laser. Second is patient fixation. In essence, centration has co-axial requirements. For this reason even an Autonomous ablation can yield a significantly decentered ablation. (Please correct me if I am wrong) How will your software help in delivering a better centered ablation under this circumstance?

Centration is one of the major aspects when it comes to high quality treatment. Even 0.2mm off will result in a considerable increase of image aberrations. In our examples we again just tried to control the treatment as it was intended. Most surgeons center the eyetracker (and thus the treatment) on the pupil center with the patient fixating a light. We just found that the ablation had not been performed well centered above the pupil which we imaged simultaneously in some cases. Once the surgeon (or the laser) has taken an image with our technology with optimum fixation of the patient this eye position is registered in 3d space. Any eye movement during the laser treatment leading to decentration will be detected with the following measurement. This will be accounted for immediately during the treatment. Nevertheless we need a well aligned eye in the first place as a reference. We have some ideas how to stabilize the patient's head during the treatment. We believe this is also an important point going in the same direction.

With the future hopes to perform prolate ablations (and its concomitant tissue consumption limitations) will you system software allow for such ablations?

we only control if the ablation is performed as intended. We do not propose any specific ablation algorithm, be it prolate or wavefront derived. We make sure that your patient's eye gets what you want it to get.

The Autonomous laser is believed by many to have the most efficacious tracker. Have you been working with there technicians?

Yes, we are in contact with Alcon. Their tracker is fast but requires pupil dilation which is not always nice. As any other tracker it only registers in two dimensions. A tilting eye cannot be accounted for. Unfortunately eye movements are not only lateral but also rotational. For the treatment itself this might not be so important. We on the other hand need higher accuracy. We thus track in three dimensions for our measurements.

Maybe we can help!