IP News

In American Medical Systems, Inc. & Laserscope v. Biolitec, Inc., No. 2009-1323, 2010 U.S. App. LEXIS 19077 (Fed. Cir. Sept. 13, 2010), the Federal Circuit reversed and remanded a district court's decision granting defendant Biolitec's motion for summary judgment of non-infringement with respect to U.S. Patent No. 6,986,764 (“the '764 patent”), holding that the district court erred in finding that the term “photoselective vaporization of tissue” in the preamble of the asserted claims was a limitation.

The '764 patent relates to treatment of Benign Prostatic Hyperplasia (“BPH”), a condition in which growth of the prostate gland restricts the passage of urine out of the bladder and through the urethra. Vaporization, or ablation, of some of the prostate tissue reduces the size of the prostate and can relieve bladder outlet obstructions. As described in the patent, this type of BPH treatment generally involves the insertion of a cytoscope into the urethra, an irrigant such as sterile water, and the application of high intensity laser radiation to the target tissue. The specification of the '764 patent explains that prior art tissue vaporization systems were inefficient since they used longer wavelengths of laser radiation e.g., 1064nm and 2100nm, which resulted in “no selective absorption by blood,” and, as a result, violent tissue disruption and “poor hemostasis” (stoppage of bleeding). The specification of the '764 patent explains that laser radiation at a wavelength of 532 nm “is selectively absorbed by blood, leading to good hemostasis.” The patent notes that prior art techniques were inefficient even at wavelengths of 532nm, and therefore teaches the use of high “volumetric power density” to increase vaporization efficiency and minimize residual coagulation.