The University Record, November 26, 1997
Top photo shows a magnified rabbit eye as the laser procedure is being performed in the cornea. The circular pattern of speckles in the center is inside the cornea itself--approximately one-eighth inch below the surface. These speckles are actually tiny gas bubbles created as the ultrafast laser vaporizes tissue. The laser is fired several thousand times a second in a computer-controlled spiral pattern. Since the beam is focused inside the cornea, surface layers are not affected by the procedure. Magnification: 2X.
Bottom photo shows the rabbit's eye one week after surgery. The cornea returns to normal clarity within one day of the procedure. Photo by Csaba Martonyi, Kellogg Eye Center
Health System Public Relations
A license agreement for a new U-M company--IntraLase Corporation--thatwilldevelop and market a new generation of lasers for eye surgery and other high-precision medical applications was approved by the Regents at their meeting last week. The company is being formed in collaboration with Escalon Medical Corp. of Skillman, N.J., with financing from the Enterprise Development Fund of Ann Arbor.
"IntraLase ophthalmic lasers will deliver extremely short pulsesof light, which can cut within the delicate structures of the eye, such asthe cornea, while avoiding damage to overlying or adjacent tissue--something not possible with current clinical laser technology," says Ron Kurtz, assistant professor of ophthalmology at the Medical School and a co-founder of the company.
According to co-founder Tibor Juhasz, associate research scientist in the Kellogg Eye Center and the Center for Ultrafast Optical Sciences (CUOS), IntraLase will develop its first products for refractive surgical procedures, which correct near-sightedness and other vision deficiencies. The company will then target glaucoma, cataract and dermatological surgery.
"IntraLase demonstrates the U-M's many strengths as a research university, especially its capacity to integrate new technology with basic research and turn it into a life-enhancing medical intervention," says Marvin G. Parnes, assistant vice president for research. "Combining U-M intellectual property with complementary patents and technology from Escalon will expedite bringing this exciting technology to the public."
"This collaboration between Escalon and U-M makes best use of our technology and has a high probability of future success," says Escalon chairman and CEO Richard J. DePiano, chairman and CEO.
Founded in 1987, Escalon develops, markets and distributes ophthalmic medical devices and pharmaceuticals, has developed a commercial ultrafast laser for clinical applications and is developing an ophthalmic drug delivery system. Escalon has headquarters in Skillman, N.J., and manufacturing operations near Milwaukee, Wis.
Funding for IntraLase is being provided by the Enterprise Development Fund, an Ann Arbor venture capital firm. "EDF is pleased to participate in the financing and development of IntraLase Corporation," says general partner Thomas S. Porter. "Combining U-M and Escalon technology will put the company in a position to develop the next generation of ophthalmic lasers and capitalize on the rapidly growing laser eye surgery market."
Animal testing to determine the safety and effectiveness of IntraLase lasers will be conducted at the Kellogg Eye Center under a sponsored research agreement also approved by the Regents. Future human clinical trials also are planned pending review and approvals by the Food and Drug Administration and the U-M's institutional review board.
CUOS was established in 1991 with funding from the National Science Foundation (NSF) and the state to advance ultrafast laser science and technology, and since then has launched several start-up firms and licensed many patents. According toGerard A. Mourou, professor of electrical engineering and computer science and the center's director, CUOS scientists will continue to conduct research on additional ultrafast laser medical applications in collaboration with the Kellogg Eye Center.
In addition to NSF, basic research funding has been provided by the Office of the Vice President for Research, the College of Engineering, the W.K. Kellogg Eye Center, the Research to Prevent Blindness Foundation and the Midwest Eye Bank and Transplantation Centers.
The U-M has been awarded a patent on the ultrafast laser technology, which has additional non-medical applications in many areas of materials processing and manufacturing.
What technology is currently used in visioncorrection surgery?
In a procedure called photorefractive keratectomy (PRK), ophthalmologists use excimer lasers to ablate or burn away surface layers of the corneaća transparent lens-like structure responsible for most of the eye¼s focusing ability. PRK is approved by the Food and Drug Administration to correct nearsightedness and some forms of astigmatism by flattening the shape of the cornea. "However, the patient can experience temporary pain after surgery and recovery of normal vision is gradual taking anywhere from a few days to a few weeks," says Alan Sugar, professor of ophthalmology and a refractive surgeon at Kellogg Eye Center.
To speed recovery, a mechanical device can be used to cut a superficial flap in the surface layers of the cornea, which is then pulled aside giving the excimer laser access to deeper corneal tissue. "Since surface structures are not damaged in this LASIK procedure, it is relatively painless and vision returns more quickly," Sugar explains. "This is a much more complex procedure than PRK. Because it relies on a mechanical device, there are risks of malfunction and associated occasional complications."
What advantages will IntraLase lasers offer ophthalmologists and patients?
Currently, no laser can cut tissue within the transparent cornea without causing significant collateral tissue damage, according to Ron Kurtz, assistant professor of ophthalmology and co-founder of IntraLase. Uultrafast lasers cut with greater precision, because they deliver energy in much shorter pulses lasting just a few femtoseconds. A femtosecond is one-millionth of one-billionth of a second.
Ultrafast lasers produce high surface quality cuts, and do not create large "shock waves" that can damage surrounding tissue, according to Tibor Juhasz, associate research scientist and co-founder of IntraLase. U-M studies of corneal tissue cuts made with ultrafast lasers have shown significantly higher surface quality than cuts made with longer-pulsed lasers and fewer complications than are associated with mechanical cutting devices. Ultrafast lasers also are being evaluated for other ophthalmic applications, including treatment of glaucoma and cataracts.