Indication for Intacs Corneal ImplantsThe specific subset of keratoconus patients proposed to be treated with implants corneal Intacs are those that:
- have suffered a progressive deterioration of vision, to the point that they can no longer achieve adequate functional vision with your contact lenses or glasses
- have clear central corneas
- have corneas with a thickness of 450 µ or greater at the proposed incision site
- have corneal transplantation as the only remaining option to improve their visual function.
Contraindications for useThe use of Intacs corneal implants for keratoconus is contraindicated in the following cases:
- patients with collagen vascular pathologies, autoimmune diseases or
- pregnant or lactating women
- patients with active eye conditions such as recurrent erosion syndrome
- of the cornea or corneal dystrophy, which could predispose them to complications later
- Patients taking one or more of the following medications: isotretinoin; amiodarone; sumatriptan.
Intacs corneal implants precautions
- Using the vacuum centering guide puts increased pressure on the eye intraocular.
- Continuous application of vacuum should be limited to 3 minutes as maximum. If it becomes necessary to reapply the guide to centered under vacuum, wait 5 minutes to allow perfusion to re-establish blood vessel to the eye before reactivating aspiration.
- Intacs corneal implants are not recommended for patients with the disease systemic agents capable of interfering with wound healing, such as diabetes insulin-dependent or severe atopic pathology.
- Intacs corneal implants are not recommended for patients with a history of herpes simplex or herpes zoster.
- Some patients experience a transient decrease in sensation in the
- central cornea.
- The safety and efficacy of other refractive procedures have not been established.
- Intacs corneal implants are intended for single use only and must not be reused.
- The safety and efficacy of Intacs corneal implants have NOT been established in the following cases:
- patients with progressive myopia or astigmatism, nuclear sclerosis, or other types
- of lens opacity; corneal abnormalities, or a history of surgery or
- corneal trauma;
- patients under 21 years of age;
- corneas with a curvature greater than 46 diopters or less than 40 diopters;
- corneas less than 450 µ thick at the proposed incision site; or
- long-term use.
Preparation for Intacs Corneal Implants
- The surgical field should be prepared by washing and or cleaning with a solution of povidone-iodine. In case the patient is allergic to povidone-iodine, other surgical scrub solutions may be employed.
- Apply 2.5% povidone-iodine solution to the cul-de-sac to reduce to a
- minimally introducing microorganisms into the incision or stromal tunnel. Leave act for two minutes and rinse thoroughly with balanced saline solution.
- Between five and ten minutes before the intervention, clean the palpebral edges with a 5% povidone-iodine solution. Do not dilute. Let the area dry by air and remain on the eyelid edges throughout the intervention.
- A standard procedure should be followed to prepare the surgical field
- ophthalmic. The implantation of Intacs must be carried out in a lint-free environment, avoiding the use of gauze and other materials that contain cotton fibers. The surgeon and the scrub nurse should wear powder-free gloves.
- At the end of the intervention, a combination of antibiotic and steroid ointment or solution is used.
- The operated eye must be protected with a patch until the next day. The patient must put on the patch every night for three to six weeks to avoid rubbing during eye healing.
- All surgical instruments are supplied NON-STERILIZED, and therefore, they must be cleaned and sterilized before each use. Inspect all surgical instruments and implant packaging Corneal Intacs to verify that they are not damaged or defective.
- It is not recommended to use pilocarpine to contract the patient’s pupil during the intervention because this can cause chemosis and cause subsequent fixing problems with the vacuum centering guide.
- To prevent neovascularization in the incision region, you need to take special precautions to ensure that the incision is located approximately 1 mm from the limbus.
- In the event of perforation of the anterior chamber, discontinue immediate intervention and remove the segments that have been implanted.
- Verify that the diamond blade is at 68% of the pachymetry reading obtained for the incision area (a minimum of 450 µ of tissue required corneal in the incision area).
- To avoid shallow stromal tunnel formation, create pockets at the maximum depth of the incision and determine the depth of the pockets.
- Closely monitor the tunnel dissection. If you experience a greater resistance or a corneal tissue wave is observed forming in front of the tip of the dissector, suspect that the tunnel does not have enough depth. Consider interrupting the dissection to create a deeper pocket and tunnel.
- To minimize dehydration of the corneal epithelium, irrigate the cornea frequently and avoid the use of excessive lighting during an intervention.
- Intacs segments should not be deposited on the corneal surface before insertion, as this could cause adhesion of epithelial cells or the penetration of bacteria into the intrastromal tunnel. Additionally, Intacs segments should be prevented from coming into contact with iodine before insertion into the intrastromal canal.
- Before closing the incision, verify that each segment is implanted correctly with the placement hole close to the incision site. If the inspection reveals that the placement hole is at the bottom of the eye (away from the incision), remove the segment and repeat the procedure.
- The necessary precautions should be taken to apply uniform tension to the sutures; however, excessive tightening of the sutures should be avoided, as it could induce astigmatism.
• Mild blurring of vision.
• Slightly distorted vision, where straight lines look bent or wavy.
• Increased sensitivity to light and glare.
• Eye redness or swelling.
• The corneal tissue that leads to keratoconus may be due to an imbalance of enzymes within the cornea.
• This imbalance makes the cornea more susceptible to oxidative damage from compounds called free radicals, causing it to weaken and bulge forward.