ENTERING THE PATENT ZONE, PART 3: Optical Feedback Patents Discovered
ENTERING THE PATENT ZONE: PART 3
Optical Feedback Patents Discovered
Irving J. Arons
As a wrap up to this three part trilogy on medical lasers and patents, or "welcome to the patent zone", I would like to tell you about a patent, and the story behind it, that few of you probably know about yet. But which many of you may wish to know about, as I believe it may play an important role in the future of medical lasers.
While wearing my other hat as a consultant to the medical laser industry, I am in the process of preparing a report on the potential for a laser-based diagnostic system to determine the thickness of severe burns. While doing a literature search on the subject, I came across an obscure reference to a company called Silicon Surgical, which was supposedly developing a closed-loop laser system for imaging the depth of a burn and removing the necrotic eschar down to viable tissue. In trying to contact the company, I was told by the people at the medical newsletter where I had seen the notice that the company "hadn't made it and was no longer in existence". Not one to give up that easily, I made further inquiries, and thanks to Dr. Norm Nishioka of Mass General's Wellman Laboratories, I was able to contact the founder and guiding spirit behind Silicon Surgical, Dr. Paul Lovoi.
It turned out that Dr. Lovoi was coming to Boston on business and agreed to meet with me and tell me his story. We met on my back porch in mid-July, and over a glass of lemonade, I learned the background of how Paul came to be the patent holder of a basic patent for the use of optical feedback to perform surgery with lasers.
It seems that Paul and his partner, Len Reed, left ILC Technology in 1978 to start a business using a pulsed flashlamp light to remove paint from airplanes and other structures for the military. When the flashlamp source proved inadequate for the task, they turned to lasers, and under a 1981 contract for the Navy, came up with the concept of using optical feedback to determine when the laser's energy had removed the paint down to the underlying primer (or any underlying layer with a distinguishing signature). It seems that different materials have different spectral signatures, and by using an optical (spectroscopy) feedback system, they could stop the laser before damaging the underlying primer, or other layer. Understanding the importance of patents in business, Paul and Alan Frank, of Lawrence Livermore Labs, applied for and received a patent for this application, U.S. Patent #4,588,885, "Method and Apparatus for the Removal of Paint and the LIke from a Substrate", issued May 13, 1986. Later in 1986, the team thought about the need for a feedback system to control laser energy in surgery, and in May 1986 filed their patent application which resulted in U.S. Patent #4,737,628, "Method and System for Controlled and Selective Removal of Material", issued April 12, 1988. The patent describes both the method and apparatus for the controlled removal of tissue using spectral reflectance of optical radiation to control the action of the surgical laser, for example, in the selective removal of a tumor without damaging adjacent tissue.
And now, like Paul Harvey says, "For the rest of the story!"
About the time of the issuance of the optical feedback patent, at least two companies were attempting to use similar systems to remove plaque in occluded arteries. MCM, and its "smart laser", was using spectroscopic feedback to direct the laser energy only against the plaque, allegedly leaving the arterial wall unaffected. That approach never really got off the ground, but another company, GV Medical (now called SpectraScience), in conjunction with a license to the work of Dr. Michael Feld of MIT, was also attempting to use optical feedback in conjunction with its LASTAC balloon catheter. This group was using laser-induced fluorescence for the discovery of plaque and ablating only the plaque attached to arterial walls. In filing for its own patents on the use of optical feedback, MIT came across the Lovoi patent, and claiming prior art, filed an interference action, trying to split the Lovoi patent into two parts; the base patent and one covering its use in angioplasty. That attempt failed, and MIT withdrew its interference action. This is perhaps why SpectraScience is no longer involved in diagnosis and therapy, but only developing the diagnostic portion of their technology!
This gets us back to Silicon Surgical. Paul Lovoi, president and CEO of INTA, the laser-based paint stripping company in Santa Clara, CA, would still like to get Silicon Surgical up and running. He is seeking a CEO for the firm and is in the process of licensing the combined burn diagnosis and therapy system under development at Wellman Labs. When the development is completed, he would like to bring it to market under the aegis of Silicon Surgical. Paul is also looking at developing and marketing other laser-based systems potentially useful for solving medical problems that could involve the use of optical feedback coupled to laser therapy, including the treatment of skin tumors and surface cancers.
So this is to put all of you involved in using lasers in combined optical feedback and therapy on notice (see Jeff Manni's article, "Feedback Devices Increase Surgical Precision" in last month's MLR). You might want to contact Dr. Lovoi and discuss his patent. He has told me that he is willing to grant non-exclusive licenses at reasonable royalties, so that both the system developer and he can make some money from his idea. Paul can be reached at 408-748-9955 (fax 408-727-3027).