|Procedure is an alternative to human-donor corneal transplants
LANGHORNE, Pa., December 10, 2008 – In another medical first for the region, artificial corneal implant surgery was performed at St. Mary Medical Center by ophthalmologist Dr. Sadeer Hannush. Artificial corneal implants are an alternative to corneal transplant surgery, which uses tissue from a human donor.
Dr. Hannush uses the Boston Keratoprosthesis for artificial cornea implant. This device received FDA approval in 1992 and is the most commonly used artificial cornea in the United States and in the world.
“This technology continues to evolve and the device presents a great alternative for patients, especially for those in which the corneal transplants they received have been rejected,” says Dr. Hannush.
Corneal transplants serve to restore sight to people who otherwise would be permanently blinded as a result of corneal injury, infection, or degenerative disease. Human donor transplantation is the most common treatment for severe corneal opacity. However not all patients are suitable candidates for transplants and even in those who are, transplants can fail, repeatedly in some cases. About 40,000 corneal transplants are performed in the United States each year, while less than 1,000 artificial corneal implants are done. Dr. Hannush performed the first artificial corneal implant at St. Mary in summer 2008 and has several others scheduled before the end of the year.
The cornea acts as the eye's outermost lens and focuses the entry of light into the eye. When the cornea becomes cloudy as a result of disease or injury, light cannot penetrate the eye to reach the light-sensitive retina. Poor vision or blindness may result if the cornea cannot be replaced. Disease or injury to the cornea is the second leading cause of blindness worldwide
An artificial corneal implant can be used after the failure of a donor transplant or for patients in which a transplant would be unlikely to succeed or in cases where there is a shortage of donors or religious barriers to human tissue transplant. The artificial implantation is a procedure designed to help patients whose conditions are the most difficult to treat.
The keratoprosthesis is made of clear plastic with excellent tissue tolerance and optical properties. It consists of three parts but when fully assembled, it has the shape of a collar-button. The device is inserted into a corneal graft, which is then sutured into the patient’s cloudy cornea. If the natural lens is in place, it often is removed. In most cases, a soft contact lens is used over the surface as an additional protective barrier.
The procedure is still quite rare and Dr. Hannush relates that he is among about 17 opthamologists nationwide who have performed artificial corneal implants.
“I have been working on the artificial cornea project since 1991, and have implanted dozens of the modern version,” Hannush says. “In 2005, I performed the first keratoprosthesis in US military history on a young soldier injured in Iraq and led the surgical team that performed the first artificial cornea transplant in Italy in June 2008.”
Patients with end-stage glaucoma or retinal detachment are not suitable candidates for this procedure and all patients must have a physician referral to be seen for evaluation by Dr. Hannush. Dr. Hannush has an office in Middletown.