Epi-on or epi-off Cross-linking?

We are often asked which CXL treatment methods we prefer, most frequently on so-called “epi-on” or “transepithelial” cross-linking. We only do this in special cases. Our method of choice is still the classic “epi-off” cross-linking. Here’s why.

Epi-off Cross-Linking

The first step of classical cross-linking requires the removal of the outermost layer of the cornea, the corneal epithelium, so that riboflavin (vitamin B2) can penetrate the cornea correctly. The success rate of this “epi(thelium)-off” protocol is extremely high, well over 90%. A relative disadvantage is that the cornea has to heal again. In the first few days there are inconveniences such as a burning and biting sensation in the eyes, and of course you have to make sure that no infection occurs. However, with professional surgery, patient education and meticulous follow-up, these risks are extremely low. We have not seen a single case of post-CXL corneal infection in 10 years.

Play Video

Epi-Off Cross-Linking Procedure

Epi-on Cross-Linking: not yet 

The idea of ​​epi-on cross-linking came up because it does have theoretical advantages: less postoperative burning sensation of the eyes and a reduced risk of infection. After an initial euphoria, the “hype” about epi-on cross-linking has subsided. The reason is that the success rate, which is well over 90% for the classic “epi-off” CXL, falls to 60–70% for the epi-on procedure. Why?  In 2013, our research group discovered that in addition to vitamin B2 and UV light, the presence of oxygen is another essential factor for successful cross-linking.

Ribovlavin

Oxygen

CXL

Ultraviolet

In a detailed study in our basic science labs, we were able to show that CXL can only work if there is enough oxygen.

Oxygen must penetrate into the cornea and this is prevented by the corneal epithelium. Accordingly, several clinical studies, including a Multi-center study under our guidance, showed that the efficacy of epi-on cross-linking is only 60-70%.

International leading cross-linking experts, including Prof. Hafezi from ELZA, commented on this in January 2018.

Our Choice

We find that the most effective method is also the best method for our patients, even if it means that the healing takes a little longer. What use is a “gentle” method, if it does not work?

Therefore, in most cases we do an “epi-off” cross-linking. An exception are cases where we fear that there could be infections after surgery due to poor patient co-operation, for example, severe eye rubbing after surgery. This mostly concerns small children and people with a developmental deficit. Here we apply an “epi-on” cross-linking. This is deliberately less effective because we have to avoid infections after surgery.

Farhad Hafezi was interviewed during ESCRS 2019, held in Paris, France, by Touch Medical Media on how CXL is performed at the slit lamp.
The annual meeting of the European Society of Cataract and Refractive Surgeons (ESCRS) was held in Paris between 14–18 September 2019, and ELZA’s surgeons and researchers presented a record 21 presentations during the congress – so what did ELZA at ESCRS manage to achieve? Our team presented at 8 free paper presentations and a further 8 instructional courses, as well as three moderated poster sessions, two e-posters (as well as instructing in 1 wet lab too).
The annual meeting of the European Society of Cataract and Refractive Surgeons (ESCRS) was held in Paris between 14–18 September 2019, and ELZA’s surgeons and researchers presented a record 21 presentations during the congress – so what did ELZA at ESCRS manage to achieve? Our team presented at 8 free paper presentations and a further 8 instructional courses, as well as three moderated poster sessions, two e-posters (as well as instructing in 1 wet lab too).
The Cross-Linking Experts 2018 Meeting 2018 Zurich, organised by the Light for Sight Foundation,  took place in Zurich for the 14th consecutive time
Swiss ophthalmologist receives an award in Russia: The ophthalmologist Farhad Hafezi from the ELZA Institute gave the honorary lecture at the renowned Fyodorov Microsurgery Eye Institute in Moscow

The ELZA Institute

EN | DE

Augeninstitut ELZA
4.7
Based on 80 reviews
powered by Google
Thomas S.
Thomas S.
09:37 07 Jul 21
My left eye had to be operated on because of a cataract. As I had an Artiflex lens implanted a few years ago, it had to... be removed first before a modern lens could be implanted to correct the cataract. Prof. Hafezi treated me in an very competent and friendly manner. I am very happy with the result.read more
Selma A. Rahim
Selma A. Rahim
19:45 02 Jul 21
Dr. Hafezi.. the KING OF CXL🤴
Gianluca Ricci
Gianluca Ricci
12:46 10 Apr 21
Great team and service!
rehaneyecare
rehaneyecare
05:36 08 Apr 21
Excellent surgeon
Steven H.A
Steven H.A
16:13 11 Jan 21
Prof. F. Hafezi s expertise is enormous and he has a very pleasant and calm nature which gives the patient... security.Thank youread more
Online Commande
Online Commande
09:19 05 Dec 20
Totally creepy, very arrogant Prof.He just want your money.It may explain, why this Prof. is not in the center of the... city of Zürich and why he has been thrown away from University of Geneva.read more
Elena Churilova
Elena Churilova
10:06 17 Nov 20
At the moment, 3 months have passed since the moment I made laser vision correction in this clinic. and I can say that... I am happy that I chose this particular clinic and Prof. F. Hafezi. The entire staff of the clinic is very friendly, treats patients with sympathy and patience if they are nervous before surgery (my big gratitude to Aida Alili for all support and patience). The doctor Hafezi and other doctors of the clinic are very professional and ready to explain to you as many times as you need. I can only recommend!read more
Next Reviews
Augeninstitut ELZA
4.7
Based on 80 reviews
powered by Google