Photorefractive Keratectomy (PRK)
Photorefractive keratectomy, or PRK, is one of the safest and most time-tested laser vision correction procedures available. Before LASIK, PRK was the most common refractive surgery procedure. Like LASIK, it reshapes the cornea to improve vision. PRK is now used mainly for patients with large pupils or thin corneas.
The first step in PRK is to remove the epithelium, a thin layer protecting the cornea. Then the surgeon uses an excimer laser to vaporize a small amount from the top of the cornea. LASIK, by contrast, cuts a deep flap in the cornea using a sharp microkeratome blade. This weakens the cornea, makes it difficult to replace the flap in precisely the right place, and can cause other complications including flap irregularity, epithelial ingrowth and corneal ectasia. PRK avoids these risks.
Studies have shown that 90-95% of patients with a correction of up to -6.00 diopters achieve vision of 20/40 after PRK, and up to 70% achieve 20/20. Patients needing less correction generally achieve better results. The risks of PRK include infection, haze, slow healing, scarring, over- or under-correction of the visual condition, and development of astigmatism.
ProKera is a cutting-edge medical device designed to help heal and protect the surface of the eye. It is used in the treatment of recurrent corneal erosion, keratitis, ocular herpes, severe dry eye syndrome and several other corneal disorders. ProKera consists of a segment of amniotic membrane tissue fitted between two clear, flexible rings.
Amniotic membrane is found within the human placenta. The placentas used in ProKera are donated by medically screened women after cesarean-section childbirth. The membrane is then cryopreserved and saved in a tissue bank regulated by the FDA.
ProKera serves as a biologic bandage, promoting healing, reducing inflammation, relieving pain and minimizing scarring in the eye. It will also protect the surface of the eye from external irritants. ProKera is placed on the eye by a physician and patients should not remove it unless otherwise instructed. It is similar to a contact lens in shape, but slightly thicker, so some patients do experience discomfort for an adjustment period.
Pan Retinal Photocoagulation for Proliferative Diabetic Retinopathy
Pan retinal photocoagulation is a minimally invasive laser procedure used to seal or destroy leaking blood vessels on the retina. This form of treatment is effective in preventing the growth of new blood vessels around the retina to maintain vision in patients with proliferative diabetic retinopathy, an advanced stage of diabetic eye disease.
During pan retinal photocoagulation, a laser beam is directed to the blood vessels that are leaking on the retina. The laser creates scar tissue around the area that slows the growth of any new or abnormal blood vessels. While it is unable to restore vision that has already been lost, laser photocoagulation can reduce the risk of vision loss, a major complication of proliferative diabetic retinopathy.
The pan retinal photocoagulation procedure is usually performed on an outpatient basis with a local or topical anesthetic. Patients will need someone to drive them home after the procedure, since the pupils will be dilated for several hours. After the pan retinal photocoagulation procedure, patients may experience blurry vision and mild pain for a day or two. Normal activities may be resumed with the surgeon’s approval.
Pterygiectomy with AMG & MMC
Pterygium is a painless, non-cancerous growth of the conjunctiva, the lining that covers the white part of the eye. The pterygium may grow on the cornea, which covers the iris, the colored part of the eye. In mild cases of pterygium, artificial tears can be used to reduce the dryness and irritation it causes.
For patients with severe cases of pterygium and whose vision has been affected, surgery known as a pterygiectomy is the only way to definitely remove this growth. This may be achieved through two different types of pterygiectomies, either using tissue taken from another part of your body or an amniotic membrane graft.
Autologous conjunctival auto-grafting is a safe and effective technique to surgically remove a pterygium. The pterygium is removed as well as the conjunctival tissue covering the sclera. Tissue is removed from the inside of the patient’s upper eyelid to replace the tissue that is removed from the sclera.
Amniotic membrane graft (AMG) is another safe and effective procedure to remove a pterygium. Tissue is removed from an inner layer of the human placenta and is used to reconstruct the surface of the eye. This type of graft encourages healing and reduces swelling.
Mytomycin C, or MMC, is a chemical agent that inhibits the production of scar tissue. It can lower the odds of pterygia growing again. This is important since they typically have a recurrence rate between 30 and 40 percent. In cases of recurring pterygia, MMC may be applied to the eye during a pterygectomy, then thoroughly rinsed out. Since damage to the sclera or vision loss can be complications of an MMC application, it is essential to choose an experienced physician to perform this procedure.