KERATOCONUS
Keratoconus is corneal ectasia of disputed etiology which leads to cornea thinning and consequent deformation into a conic shape, which triggers the occurrence of high regular astigmatism and consequent reduction of visual acuity.
Keratoconus is always bilateral and asymmetrical, and manifests during adolescence.
SYMPTOMS
Keratoconus may be hard to detect and, habitually, emerges slowly. However, in some cases, keratoconus can progress rapidly. As the cornea shape becomes increasingly irregular, there is gradual vision loss. Glare and photophobia might occur as well.
Keratoconus patients tend to have their lens prescriptions renewed each time they visit their ophthalmologist.
Quite frequently keratoconus diagnosis comes late if ophthalmologists are not familiar with such cases and do not identify the early stages of the disease.
CAUSES
Keratoconus is a progressive degenerative condition and can occur at any age in the life of a person.
Most of patients are diagnosed early during adolescence, when the disease progresses more aggressively.
Major risk factors are heredity and allergic conjunctivitis normally associated with constant eye rubbing.
FERRARA RING™
In the early stages of keratoconus, contact lens fitting or glasses can help patients. As the disease progresses, cornea thinning increases the irregularity of its shape and hinder the improvement once provided by glasses or lenses.
The Ferrara Ring® is a surgical alternative which delays or eliminates the need for corneal transplantation.
Keratoconus may be hard to detect and, habitually, emerges slowly. However, in some cases, keratoconus can progress rapidly. As the cornea shape becomes increasingly irregular, there is gradual vision loss. Glare and photophobia might occur as well.
Keratoconus patients tend to have their lens prescriptions renewed each time they visit their ophthalmologist. Quite frequently keratoconus diagnosis comes late if ophthalmologists are not familiar with such cases and do not identify the early stages of the disease.
Keratoconus is a progressive degenerative condition and can occur at any age in the life of a person. Most of patients are diagnosed early during adolescence, when the disease progresses more aggressively.
Major risk factors are heredity and allergic conjunctivitis normally associated with constant eye rubbing.
SCLERAL FITTING LENSES
Scleral lenses are larger-diameter contact lenses, suitable for irregular corneas, and can help keratoconus patients.
However, scleral lenses do not treat keratoconus and if its progression is observed, a Ferrara RingTM implant can be recommended.
CROSSLINKING
Crosslinking emerged as an approach in the treatment of keratoconus around 10 years ago.
Riboflavin application associated to ultra-violet light in controlled intensity strengthens corneal collagen structures making the cornea more rigid and resistant to deformation.
In advanced cases of keratoconus, a Ferrara RingTM implant is recommended to correct corneal irregularity and, in case of disease progression, Crosslinking application may be recommended.
CORNEA TRANSPLANT
A cornea transplant is the last resort for treating keratoconus.
Even after a transplant, a Ferrara RingTM implant might be made necessary if post-transplant/post-keratoplasty irregular astigmatism is significant.
Currently, 320°arc length segmentsmay be indicated for advanced cases of keratoconus and postpone the need for cornea transplant.
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.
