The Johns Hopkins Gazette: May 29, 2001
May 29, 2001
VOL. 30, NO. 36


Eye Drops Could Help 'Haze' After Laser Surgery

Product developed by three research partners is APL Invention of the Year

By Michael Buckley
Applied Physics Laboratory

Johns Hopkins Gazette Online Edition

Eye drops that could speed healing and prevent blurriness after laser vision correction surgery captured the Applied Physics Laboratory's Invention of the Year award in a reception May 11 on the APL campus. The Lab held the second annual ceremony to honor 225 researchers and name its top inventions for 2000.

APL director Richard Roca and Wayne Swann, director of the Office of Technology Transfer, presented plaques and cash awards for the Lab's top four developments. Other honorees included a computer network security system, an ultrasonic tooth-checking laser and a method to detect bridge corrosion using sound waves. An independent panel of business and industry representatives, technical and business consultants, technology transfer professionals and intellectual property attorneys picked the top inventions from 135 nominees based on their creativity, novelty and potential benefit to society.

The winning invention was titled "Plasminogen Activator to Prevent Haze After Laser Vision-Correction Surgery."

Of the millions of people who undergo laser vision-correction surgery each year, less than 10 percent encounter cloudy vision several months after the operation. David Silver of APL and Andras Berta and Adrienne Csutak of the University Medical School of Debrecen (Hungary) have developed eye drops to prevent this "haze" from forming in the cornea.

The drops are a plasminogen activator, which stimulates an enzyme that counters irregularities in the corneal healing process. Doctors can't yet predict which patients will suffer from cloudy vision, so the researchers believe the drops could be provided to every patient after surgery. They also believe the drops are harmless to those who wouldn't otherwise develop the haze, and could speed healing in other procedures involving incisions to the cornea.

The research partners will share a $2,500 cash award for the top invention. In January APL optioned the rights to the drops to Paradigm Medical Industries of Salt Lake City, which estimates the product could eventually generate annual revenues of $500 million to $1 billion.

Three inventions were named as finalists, with each team receiving plaques and a $1,000 cash prize. They were:

"Assessment of Tooth Structure Using Laser-Based Ultrasonics"

Dental health workers continually search for new ways to check tooth and adjacent bone structures. Conventional X-rays have difficulty imaging cracks and interfaces between hard surfaces, and they can't reveal decay at a stage early enough to avoid invasive restoration procedures.

APL researchers David Blodgett, Kevin Baldwin and Donald Duncan have devised a laser-based ultrasound system using short, high-frequency pulses to image interior dental structure--including the interfaces between different layers--and detect early signs of decay. The noninvasive system requires no special preparation of tooth surfaces and causes no damage to materials. Its laser beam can be focused to diameters just tens of microns across to detect problems such as poor bonding or voids at the margins of a filling. Other clinical applications of the system potentially include visualizing periodontal defects, localizing lesions within the bone and assessing the bond between a dental implant and the surrounding bone.

"Detecting Rebar Corrosion in Reinforced Concrete Structures Using Modal Analysis"

This highway safety invention uses sound waves to detect corrosion in the metal bars (rebar) that form the framework for most bridges and roads. Because corrosion buildup on the metal leads to fractures in the concrete--which could ultimately compromise the structure's mechanical strength--a noninvasive test that can be used regardless of the homogeneity of concrete elements is an important advancement in highway safety.

APL's David Blodgett and George Vojtech crafted a process that uses sound waves to detect debonding of cement around corroding rebar. The sound waves cause the rebar to vibrate, sending acoustic waves to the surface of the concrete, where a laser vibrometer can detect them. More corrosion means more debonding, which produces higher frequency acoustic waves.

"Neural Network Intrusion Detection System"

APL's Susan Lee developed a system encompassing a hierarchy of neural networks that work in concert to detect cyber attacks against an enterprise's computer network. Current intrusion detection systems are largely ineffective because they're trained to recognize known attacks, so novel, never-seen-before attacks can slip past them. Other systems, designed to recognize "normal" actions (as a way to detect normal and anomalous activity), are often confounded by the extreme range of normal behavior.

By monitoring selected, predictable network behaviors, APL's neural network-based system functions as a true anomaly detector, becoming increasingly adept at recognizing attacks it has never encountered. The technology has been licensed nonexclusively to the Sphere Corporation of Columbia, Md., an APL spin-off company formerly known as GuardedProfile.

All four innovations were part of a productive year for APL's Technology Transfer Office. Since December 1999 APL has spun off four new Maryland companies, licensed 20 technologies, earned more than $2 million in licensing income and secured more than $1 million for research and development through technology transfer agreements.

For the latest on APL's technology transfer initiatives, go to