Frequently asked questions


I am from the USA and the travel distance to Austria is rather far. Is there a possibility to assess whether or not I am eligible for CISIS before travelling to Austria for a medical exam?


If you contact us via our website and if you are ready to submit the necessary data, we can evaluate in advance if undertaking the trip to receive the actual medical exam makes sense. For this purpose, we need the following data:


K-values (SIM K)

Corneal thickness

Visual acuity without correction



As my trip to Austria (Europe) is longer than 800 km, I would like to know whether or not the examination and the treatment can be conducted during the same trip.


Pre-operative examination: Monday

Surgery: Tuesday

Post-operative examination: Wednesday

The pre-operative examination, the treatment itself and the post-operative examination take place in Wels:

Health center

Salzburgerstrasse 65

4600 Wels

Most trains between Vienna Airport and Salzburg stop at Wels. Ideally, you should submit the necessary data listed above before your arrival in order to allow us to evaluate the chances of a satisfying treatment in advance.   


Where does Dr. Daxer offer treatment?

The CISIS/MyoRing treatment is done in Wels (Austria) and Munich and Hamburg (Germany).



Munich +49-151-46839683 (8 a.m. - noon)

Hamburg +49-40-42916066


Preexamination: Ybbs +43-7412-53110 (8 a.m. - noon)

Treatment: Wels +43-676-7900586 (8 a.m. - noon)


How long does the surgery take?

The surgery takes between 10 and 15 minutes and is conducted under topical anesthesia via eye drops. The surgery itself is completely painless. Usually, even after the treatment, there is no pain.


What are the results of keratoconus treatment via CISIS/MyoRing?

Worldwide, 8,300 CISIS/MyoRing keratoconus treatments were conducted by the end of 2016. Personal statistics (Dr. Daxer) covering the last 10 years count 2,000 of these surgeries. In almost 100% of all cases improvements of visual acuity were achieved. Only 3 MyoRings had to be extracted again (see below). Thus, CISIS/MyoRing can be considered as the safest method of keratoconus treatment currently available.


What are possible complications? 

Out of the approximately 2,000 surgeries which have been conducted hitherto (see above), only a very small number of complications occurred. These complications are listed on the information sheet and they occurred with the following frequency:

Perforation: 0.1%

Infection: 0.05%

Extrusion: 0.5%

Only a total of 3 MyoRings had to be removed (follow-up period 9 years): Two of them because of insufficient correction of very highly advanced cases of keratoconus, where no significant improvement of visual acuity could be achieved and where, subsequently, the initially planned cornea transplant was made. One eye suffered from extrusions (see above). CISIS/MyoRing is thus, applied by a trained specialist, by far the safest and most effective method of treating keratoconus currently available.


What are possible side effects? 

Basically, there are two side effects which have to be considered.

Halos: Halos are reflexes of light surrounding light sources during night-time. This side-effect occurs immediately after surgery in around 30% of all cases to a degree which is perceived as intruding by the treated patients. These halos decrease in frequency during the months following the surgery and become weaker. Thus, after a period of 6 months, only 2-3% of the treated patients perceive them as intruding.

Under- and hypercorrection: In around 15% of all cases, under- or hypercorrections of keratoconus occur due to the selected MyoRing. In these cases, the MyoRing has to be replaced by a weaker or stronger one after a period of 3 months. See chapter keratoconus for more details.


I am a phobic patient. Is there any possibility to perform CISIS under general anesthesia?

Usually, not. This is due to the fact that the patient has to focus on a light source inside of a microscope used during the operation after the insertion of the MyoRing. This technique is used to allow for the positioning of the MyoRing according to the actual postoperative fixation inside the cornea (taking into account the actual postoperative visual axis). This procedure is highly important and one of a plethora of differences of MyoRings as compared to ring segments. Ring segments are implanted into a circular tunnel which is adjusted to the preoperative axis. However, in keratoconus patients, the visual axis shifts due to the changes in corneal geometry, which are caused by the implant. Even a minor decentralization of less than 0.5 mm may lead to significant limitations of the postoperative visual acuity (see A. Daxer. Adjustable Intracorneal Ring on a Lamellar Pocket for Keratoconus. Journal of Refractive Surgery 2010; 26: 217-221). This is one of the reasons why the MyoRing leads to significantly better results than ring segments.


Is it true that CISIS is entirely reversible?


The MyoRing can be removed rather easily. The procedure is gentle and painless and takes less than a minute. Usually, the condition of the eye is the same as before the insertion. It is only in rather rare cases that the MyoRing has to be permanently removed in cases of keratoconus.


Is the MyoRing capable of stopping the progression of keratoconus?


Follow-up observations which cover time spans of up to 9 years show that there is practically hardly any progression after the implantation of the MyoRing. The explanation is as follows: The MyoRing is a full-ring and functions just like the girder of a ceiling which can take on the forces that affect the ceiling itself; a split girder could, of course, not fulfill a similar function. Thus, the MyoRing strengthens the cornea in a manner which is especially important in keratoconus treatment, as the progression of keratoconus itself is characterized by a weakness of the tissue which inhibits the cornea’s capability to withstand the pressure caused by trans-corneal pressure in the long-term. Out of approximately 1,000 patients who underwent CISIS treatment (Dr. Daxer) only one case of a questionable progression is being discussed. However, even so, only the thickness of the cornea itself is subjected to a certain temporal variation, while the postoperative k-values and the visual acuity have not changed. Thus, hitherto no intervention as part of treating progression was necessary. Should there be a rare case in which progression was an issue, which cannot be ruled out 100%, while the obtained data allows for evaluating a case like that as highly improbable, crosslinking could be used postoperatively. Hitherto, this has not been necessary. Thus, keratoconus can be considered as "healed" after CISIS/MyoRing treatment. See chapters "How can CISIS inhibit the progression of keratoconus?" and "What are the long-term results of CISIS" in the section "keratoconus".


Which one is better, MyoRing or crosslinking?

There is no generalizable answer to this question. There are certain indicators which need to be considered. Crosslinking makes sense and is effective in earlier stages of the disease when visual acuity is still high and a progression of the disease can be observed. The cornea has to measure at least 400µm. However, it has to be mentioned that crosslinking in itself does not lead to an improvement of visual acuity. Using the MyoRing makes sense and is especially effective when the patient does not have full visual acuity anymore, while wearing contact lenses causes problems for the patient. The cornea has to measure at least 350 µm at its weakest point. Basically, the MyoRing can always be used when the cornea measures 350µm or more. The MyoRing leads to improvements of visual acuity and can replace cornea transplants or contact lenses in numerous cases.


When are the sutures removed?

There are no sutures. The access to the cornea is self-sealing from the inside and the epithelium above it heals within hours after the surgery. You are mistaking the MyoRings for ring segments. In surgeries where ring segments are used, a radial cut has to be made in the cornea which can be rather wide and which can lead to considerable complications if it is not sutured.


Are there any reports of experience of patients?

We disapprove of vociferous advertisements in the medical sector. This is why we do not ask our patients to provide reports of experience on our website. A practice like this would also require personal data to be made public to the reader in order to ensure that these reports relate to actual patients and are not made up, which is common practise on numerous websites. However, if a patient decides himself/herself that he/she can help other patients by providing a report of experience in their process of decision making, we are happy to make a report like this available to the public. For example, recently Mr. Deimel, who underwent treatment of keratoconus on one eye several years ago and whose second eye has been treated recently via CISIS, provided us with a report of experience on his own account. This report was published in the journal "Diaplant aktuell" and can also be found here.


What are the costs of CISIS? 

Usually, the costs of treatment are EUR 3,000 per eye.


Do health insurance companies cover the costs of CISIS?

We know of cases in which German health insurance companies covered the costs of the treatment. The usual procedure is that after medical examination, patients receive a cost estimate along with a detailed application form of cost coverage providing detailed medical justifications. These documents can be submitted to your health insurance company. In Austria, these costs are hardly ever covered.


How can I pay?

The fee can either be paid in advance via bank transaction before the date of the surgery or on the day of the surgery in cash or via credit card payment.