Optical-imaging technologies show hope for preventing KC and other diseases
Optical imaging devices using novel laser-scanning technologies are allowing scientists to study cell processes in the eye with more depth and meaning than ever before. Using High-Resolution Laser Macroscopy, scientists at UC Irvine have been able to map out the unique, rigid structure of the human cornea. The “macroscope” creates three-dimensional data sets that, when put together, produce an accurate, full representation of the human cornea.
According to Dr. James Jester, “[With these 3-D images], we can look at the entire tissue and see how collagen is organized throughout the cornea. We have validated that there is a unique rigid structure to the cornea,” Jester says. “We also found, in those patients with keratoconus (KC), that this structure is lost.”
The images allow researchers to study how the cornea’s structure controls its shape and how it is altered in those with astigmatism and KC. The hope, Jester says, is that once they understand the mechanisms underlying these disorders, they will be able to treat and prevent them. He believes if a KC-prone cornea can be strengthened earlier using corneal cross-linking, it may be kept from ever forming cones.
Scientists have been using such technologies for years. The In-Vivo Confocal Microscope, which Jester helped develop, creates high-resolution, high-contrast images inside living tissue (biopsying the tissue without having to take it out of the patient), allowing researchers to look at the cornea 3-dimensionally and identify wound-healing processes. Jester is using it to study the corneal wound-healing response process following refractive surgery (such as radial keratotomy, PRK and Lasik). The cornea’s own post-injury healing responses can actually worsen eyesight, compromising corneal integrity and transparency, largely due to the scarring that takes place during the healing process.
“Some patients after these surgeries may have loss of corneal transparency and the development of blurring or haze in the cornea due to a cell that is activated and migrates in, called a ‘myofibroblast,’” Jester explains. “This cell is responsible for healing the wound and laying down new tissue, but it also scatters a lot of light causing blurring and haze. Through various in vivo confocal microscope studies, we’ve found that these cells appear in the cornea after injury or insult and are responsible for this loss of clarity in the cornea. We’ve been looking at ways of blocking and/or controlling the appearance and migration of these cells and, consequently, blocking the development of haze.”
Using these microscopes, as well as ex-vivo microscopes, femtosecond lasers (super-fast pulse lasers) and other optical imaging modalities, researchers are currently studying corneal architecture, with the goal of understanding the cellular molecular mechanisms of the cellular response and how to control them. By working with the latest advances to map and study the structure of the human corneal matrix, DEF-funded researchers are making great strides in understanding — and, ultimately, treating and preventing — vision-altering eye disease.