Fujifilm Pressure Paper
Fujifilm Pressure Paper is a mylar-based film that contains a layer of tiny microcapsules. When pressure is applied to the Fujifilm Pressure Paper, the microcapsules rupture. This results in a color change that is proportional to the intensity of the pressure. A pressure at the low range of the paper results in a pale pink color; and at the high end of the range, a deep magenta color. The term Fujifilm Pressure Paper is synonymous with Fujifilm Prescale®.
Using a densitimetric scanner in conjunction with Windows® software, the red colors on the Fujifilm Pressure Paper can be converted to a calibrated, multi-color image. This is easier to interpret than the raw image. The conversion can be accomplished using Sensor Products’ Topaq® System, the results of which are shown in Figure B below.
Fujifilm Pressure Paper has a wide variety of uses. For example, a study by Robert Allaire, et al, at the University of Pittsburgh, used Fujifilm Pressure Paper to provide biomechanical rationale for surgical repair of meniscus tears in the knee. (“Biomechanical Consequences of a Tear of the Posterior Root of the Medial Meniscus Similar to Total Meniscectomy,” Robert Allaire, MD, Muturi Muriuki, PhD, Lars Gilbertson, MD, and Christopher D Harner, MD, The Journal of Bone & Joint Surgery, Volume 90A, Number 9, September 2008) For the study, packets of super-low-pressure and low-pressure Fujifilm Pressure Paper were surgically implanted in cadaver knees. The knee joints were then tested in a custom-designed, testing jig. Some of the test results are shown in the following graphics.
Fig A: Peak Contact Pressure versus Flexion Angle; Fig B: Representative Fuji?lm Pressure Paper Distributions (after computer analysis). The arrows point to regions of increased pressure. The color scale at the bottom shows pressure values.
Additional information on the Sensor Products Web Site can be found under “Biometrics” and “Fujifilm Prescale® with Topaq® Enhancement”. Other Glossary terms that relate to Fujifilm Pressure Paper are: “Prescale®”, “Prescale® Fuji Film”, “Pressure Film”, “Pressure Indicating Film”, “Pressure Measurement Film”, “Pressure Paper”, and “Pressure Tape”.