Toward emmetropia: More advances, more improvements
Refractive, corneal surgery in 2016 saw gains in therapies for keratoconus, presbyopia
Corneal inlays for keratoconus
In line with keratoconus treatment, Dr. Hersh and colleagues have started a study of a new procedure that they have developed, called corneal tissue addition for keratoconus [CTAK].
This novel procedure uses corneal inlays prepared from preserved corneal tissue. In a study of patients with keratoconus, he is performing the CTAK procedure, in which lenticules of this preserved tissue are shaped by a femtosecond laser and inlaid via a corneal pocket.
This procedure is performed with the goal of restoring corneal tissue and thickness to severely ectatic keratoconus corneas that cannot benefit from crosslinking and are unable to undergo any other procedures for visual rehabilitation short of corneal transplantation. CTAK may restore the cornea’s viability for other procedures such as crosslinking or PRK.
This is a very early study, with only a few patients treated, but Dr. Hersh noted that the preserved corneal tissue can be shaped well and transplanted into a corneal pocket.
“The corneal tissue is clear in situ, causes no tissue reaction, healing is quick, and the corneas become clearer over time,” he said. “The tissue and thickness were restored in these early patients. The next steps are refinement of the procedure with possible adjunctive crosslinking and other interventions to improve the vision.”
Adjunctive therapies to crosslinking
With approval of crosslinking, new recent consideration might be given to the use of Intacs (Oasis Medical) or potentially PRK.
“The use of Intacs is something that might gain in popularity in the future as surgeons become more comfortable with crosslinking,” Dr. Hersh said.
The crosslinking procedure will provide the required stabilization, and the addition of Intacs can substantially improve the topography by upward of 10 to 15 D in some patients. Consideration may be given to both procedures in patients with keratoconus, since they address different aspects of the disease problem.
“In a clinical trial we have been performing, crosslinking and Intacs appear to be complementary,” he said.
The potential is also there for postoperative fitting of patients with keratoconus with scleral lenses and newer contact lens designs to aid in visual rehabilitation.