Ferrara Ring ™

Since 1996 improving results in the treatment of keratoconus.

Customer Service

Monday to Friday, from 9:00 am to 5:00 pm

+34 671 673 790


Calle Jose Ribera, 12 . Entrepinos Simancas, Valladolid . ESPANÃ


Created by Dr. Paulo Ferrara in 1987 for the correction of high myopia.

In 1996, with the advent of Excimer Laser, the Ferrara Ring™ started to be employed in the treatment of patients with keratoconus.

In 1998, Dr. Paulo Ferrara taught the first Course on Intrastromal Corneal Ring Segment (ICRS) Implantation for the correction of keratoconus.

Nowadays, this technology is present in 87 countries amounting to over 600.000 eye implants.


Manufactured with PMMA, it is fully / well tolerated by the cornea.

Available in two models, the Premium Ferrara RingTM is manufactured with Yellow PMMA (Polymethyl methacrylate – the same material used in intraocular lenses), thus providing an additional filter to blue light, which is predominantly nocturnal and can cause haloes and glare.
Throughout over 30 years of existence, knowledge built up on the mechanism of action undergone by the rings allied to new semiologic techniques and the use of Femtosecond Laser for ring implantation made the method safer and more predictable.




In addition to Keratoconus treatment, the Ferrara Ring™ is also indicated for the following ectasias:



Given the individuality of each keratoconus case, the nomogram, or the way to use the Ferrara Ring™, is a suggestion for choosing segments and surgical planning. The nomogram derives from statistics of implants performed in the past 20 years.
After observing results, we currently use Asphericity as the main parameter for indicating position, arc size and thickness of Ferrara Ring™ segments.


The Ferrara Ring™ complies with the postulates of Barraquer and Blavatskaya. According to these postulates, tissue addition to the cornea periphery results in flattening while the Ring would determine the extent to which the cornea flattens. Therefore, the more tissue is added (ring thickness) and the smaller its diameter is, the more accurate correction of myopia will be achieved.
  • Studies have additionally shown the following:
  • Interruption or delay of Keratoconus evolution
    Reduction of related symptoms such as itching, photophobia and pain and/or ocular discomfort;
  • Decrease in the depth of the anterior chamber as observed via Ultrasound Biomicroscopy;
  • Flattening
    Central and peripheral flattening with improvement of asphericity;
  • Corneal Surface Regularization
    by means of a “couppling” effected caused by segment shape;
  • UCVA
    No correspondence has been found between postoperative UCVA and residual ametropia. At times, improvement of visual acuity has been observed while coexisting with residual refractive errors;
  • Prismatic Effect
    The prismatic effect generated by the triangular cross section eliminates halos and glare which can be caused by small orthosis diameter;
  • Yellow Filter
    The yellow filter prevents blue light from entering human eyes thus reducing sensation of halos and nocturnal glare/night reflections.


ISO 9001, ISO 135485 and CE mark.

Devised and developed exclusively for Ferrara Ring™ implantation.


  • +55 31 3223 3108
  • contato@ferrararing.com.br
  • R. Maranhão, 1642 – 1º andar – Funcionários, Belo Horizonte – MG, 30150-338


  • We refer you to the nearest ophthalmologist / eye doctor.
  • The Ferrara RingTM must be recommended by your ophthalmologist.
  • Speak directly with our consultants / agents / advisors.




95% of patients who undergo Ferrara Ring Implantation do not need a corneal transplant.

In some cases it is necessary to adapt scleral lenses. In most cases, glasses or soft lenses are sufficient.

No. The surgical technique, when applied correctly, is always beneficial for the cornea.

Complications related to the surgical technique, such as implant superficiality, can result in spontaneous extrusion of the Ring. Poor positioning of the segments can generate astigmatism but is rarely observed. Complications related to post-operative care can occur when the patient scratches their eyes, which may lead to movement of the segment, spontaneous extrusion or infection.

In general, all complications are reversible with the removal or repositioning of the Ferrara Ring segments.

Complications rarely occur during surgery. The segment removal rate is less than 4% after the procedure. Infections present more serious complications and may result in the need for a cornea transplant. Fortunately infections were observed in less than 0.08% of cases.

Corneal transplantation requires a long recovery period, close to 12 months. This transplant also runs the risk of rejection and does not prevent keratoconus from appearing again. Most of the time, the use of glasses or contact lenses is necessary and the patient may still be subject to the Ferrara Ring Implant to correct a high degree of irregular astigmatism that may arise due to poor recovery from the transplant.

• Rapid patient recovery;
• Compatibility of the Ring material and the corneal tissue;
• If contact lenses are needed, adaptation is easy;
• Reversibility;
• The Ferrara Ring Implant delays or stops the progression of the disease for an indefinite period of time

The success rate depends on how severe the degree of keratoconus is. The sooner the surgery is performed, the greater the chances of success. In initial cases, the success rate is greater than 95% of cases.

The Ferrara Ring Implant flattens and regularizes the surface of the cornea, therefore correcting deformities such as myopia and astigmatism. The Ferrara Ring can also be used as a complementary technique to laser or phakic lenses to correct high myopia.

Vision recovery is quick. The day after surgery, vision improved and stabilized after three months. During this period, fluctuations in the quality of vision may occur. In the morning the vision may be good but during the day it may become more blurry. Prescription glasses or contact lenses may be necessary to complete the correction. Meanwhile, vision may be fine or slightly blurred.

There are almost no risks in Ferrara Ring Implant surgery. As with any surgery, infections can happen. In these cases, the Ferrara Ring segment must be removed. Complications are minimal and, most importantly, reversible. This means that the segment can be removed and the cornea regains its original shape. There is no risk of orthosis rejection.

The surgical procedure is carried out under complete outpatient and aseptic care. Anesthesia is local with the application of eye drops. Asepsis includes the eye, nose and eyelid region. After surgery, a bandage lens or gauze is used to prevent contact with infectious agents. The procedure is completely painless and takes approximately 10 minutes. The use of antibiotic and anti-inflammatory eye drops allows for a safer and more comfortable post-operative period. The next day the patient can resume their intellectual activities.

No. The main objective of Ferrara Ring implant surgery is visual rehabilitation. The Ferrara Ring Implant can delay the progression of the disease, avoiding the need for a corneal transplant indefinitely.

Most patients have no complaints about night vision. Corrective lenses may be necessary after Ferrara Ring implantation to correct residual ametropia.