FISO’s catheters offer significant advantages over traditional solid-state catheters, while maintaining an excellent performance in signal integrity and frequency response. The other major benefits of FISO’s catheters include: (i) no side-facing sensor measurement artifacts, which are pretty common near vessel walls, and (ii) the ability to function within an MRI machine, or high EMI/RF environments.
FISO’s catheters Benefits
Micro – No need for high-priced solid-state pressure catheters when a mass manufactured glass fiber is inexpensive and small, i.e. as small as 0.9 Fr (310 µm).
Low noise – Since a beam of light is inherently quiet, no EMI/RF from the catheter itself are interfering with the pressure signal. Plus, it isn’t influenced by high EMI/RF environments. The sensors can be made long enough to be used for MRI image gating.
Accurate – Due to the speed of light, the frequency response depends entirely on the signal conditioner. The fast 15 kHz FISO-LS conditioner ensures high fidelity pressure traces.
No signal artifact – The sensor is located at the tip of the fiber, which allows the measurement of the target signal without any signal artifact due to the vessel or cardiac wall contact with the sensor.
Proven – Over 1,000,000 sensors in the field!
Chassis
The bench-top chassis is provided with the Power/Interface module, the Evolution data acquisition and instrument control software, a USB cable, a power supply as well as, a module removal tool.
As it is inherently modular, researchers can add FPI-LS modules, and thus more channels, as time and budgets permit. The chassis offered can contain 2, 5 or 8 modules.
Module
This “signal conditioning” module is both the light source and the receiver of the fiber optic measurement system. The FPI-LS converts the optical signal into a pressure reading without the use of an external amplification box. The researcher may plug the catheter’s optical connector directly into the FPI-LS or use an (optional) extension cable with the connection box provided.
Software
Simple Monitoring and
Real-Time Graphing
Users may easily choose between reading the actual measurement or playing with user-specific screen refresh rates and graphing options (both in real time). Data may also be recorded and saved in multiple file formats. Some prefer using the 15 kHz analog output 0-5 V on the FPI-LS.
The optical pressure transducer at the heart of FISO’s catheters is based on the Fabry-Pérot (F-P) technology. A deformable membrane is assembled over a vacuumed cavity, which forms a small drum-like structure. The bottom of the drum and the inner surface of the flexible membrane form the F-P sensing cavity. The cavity length corresponds to a precise known pressure. The reflection spectrum of the F-P etalon has distinct peaks in wavelength as a function of the cavity length. When pressure is applied, the membrane is deflected towards the bottom of the drum, which reduces the cavity length. The signal conditioner is designed to be able to accurately determine the cavity length. As is, the pressure transducer and the signal conditioner form an extremely precise and repeatable pressure measurement system.