Andrew G. Iwach, M.D.Associate Clinical Professor
University of California, San FranciscoSan Francisco, California
Media BriefingUpdate on IOP Continuous
Monitoring Technologies
• I have the following financial interests or relationships to disclose:
• Consultant– AcuMEMS– Carl Zeiss Meditec– Clarity Medical Systems– IRIDEX– Lumenis, Inc.
• Lecture Fees– Alcon Laboratories, Inc. – Carl Zeiss Meditec– IRIDEX– ISTA Pharmacuticals– Lumenis, Inc.– Merck U.S. Human Health– Pfizer Ophthalmics
Financial DisclosureFinancial Disclosure
June 2011 Issue
EyeNet June 2011
• Dr. Downs created an implantable IOP transducer system
• Measures IOP a minimum of 500 times per second
• Around the clock, for as long as two years
• Sensor Adaptation of a commercial system used for drug safety studies in cardiovascular applications
• Implanted in nonhuman primates so far
Devers Eye InstitutePortland, Oregon
Downs et al.: Invest Ophthalmol Vis Sci.2011;52:7365–7375
A: Photograph of a typical T30F total implant system showing the battery/transmitter module, radio frequency (RF) ring antenna for on/off, transmission antenna, a pressure transducer, and two ECG electrodes plus groundB: Photograph of the extra-orbital surface of our custom IOP transducer housing that is secured within a ¼-inch hole in the lateral orbital wall with bone screwsC: A 23-gauge silicone tube delivers aqueous from the anterior chamber to a fluid reservoir on the intraorbital side of the transducer (partially hidden from view in B); The tube (with appropriate slack to allow for eye movement) is trimmed, inserted into the anterior chamber, sutured to the sclera using theintegral scleral tube anchor plate, and covered with a scleral patchgraft (not shown)
Courtesy of J. Crawford Downs, PhD
Downs et al.: Invest Ophthalmol Vis Sci.2011;52:7365–7375
Courtesy of J. Crawford Downs, PhD
• IOP goes up 4-12 mmHg every time you blink or move your eyes
• IOP spikes are higher in stiffer eyes and at higher basal IOP’s
• IOP is extremely variable throughout the day on the second-to-second, minute-to-minute, and hour-to-hour timescales
• IOP shows diurnal variation, although the pattern is NOT repeatable from day-to-day
• In light of these data, one wonders whether snapshot IOP measurements in the clinic are reflective of true IOP on any timescale
Comments from J. Crawford Downs, PhD
Now Entering A Different Dimension…
Source: www.sensimed.ch
Source: www.sensimed.ch
www.sensimed.ch
www.sensimed.ch
www.sensimed.ch
Glaucoma Center of San Francisco
www.GlaucomaSF.com
Glaucoma Center of San Francisco
www.GlaucomaSF.com