Review of fiber-optic pressure sensors for biomedical and biomechanical applications
Citation
Roriz, P., Frazão, O., Lobo-Ribeiro, A. B., Santos, J. L., & Simões, J. A. (2013). Review of fiber-optic pressure sensors for biomedical and biomechanical applications. Journal of Biomedical Optics, 18(5), 050903.
Keywords
- fiber-optic sensors
- pressure
- biomechanics
- biomedical
Brief
Fiber-optic sensors (FOS) are a promising alternative to conventional sensors for measuring pressure in biomedical and biomechanical applications, offering advantages such as minimally invasive procedures, remote operation, small size, and biocompatibility. While FOS have been around for about 40 years and are capable of sensing many physical and chemical quantities, there are few commercially available products. There is a lack of peer-reviewed publications and standardized testing for these products, which makes it difficult to bring them to the medical market.
Summary
Fiber-optic sensors (FOS) are becoming increasingly important in biomedical and biomechanical applications because they are minimally invasive and offer precise and accurate pressure assessment. Conventional pressure sensors such as Millar Mikro-Tip® pressure transducer catheters, while accurate, have limitations such as fragility, high cost, and susceptibility to electromagnetic interference. Conversely, FOS, particularly fiber Bragg grating (FBG) sensors, address these limitations. They are small in diameter, immune to electromagnetic fields, and provide absolute strain measurements. Different types of FOS have been used to monitor various pressures in the body including:- Intravascular Pressure: Researchers used intensity-modulated FOS to monitor intravascular blood pressure in dogs and humans as early as the 1960s and 1970s. More recently, F-P sensors such as the FOP-MIV have been used to measure left ventricular pressure.
- Intramuscular Pressure (IMP): Researchers have successfully used fiber-optic transducer-tipped catheters to measure IMP in animal and human studies. These sensors can continuously measure pressures for extended periods and are insensitive to hydrostatic artifacts.
- Intra-articular Pressure (IAP): Fiber-optic pressure sensors have been used to measure IAP during knee joint movement and in patients with cubital tunnel syndrome. FBG sensors, in particular, have shown potential for joint pressure mapping.
- Intradiscal Pressure: FBG sensors have been studied for their ability to measure pressure within intervertebral discs. These minimally invasive sensors address the limitations of larger conventional sensors, offering potential for diagnosing and monitoring spinal conditions.
- Intracranial Pressure (ICP): FOS, particularly smaller and less invasive ones, show promise in enhancing ICP monitoring. Commercially available FOS like the FOP-MIV and the OPP-M series have the potential to compete with conventional ICP transducers.
Despite the advantages of FOS, challenges remain, including the potential for mechanical fragility, the need for biocompatible protective layers for in vivo applications, and the high cost associated with some optoelectronic components.
This article provides a comprehensive review of the use of FOS in measuring pressure in biomedical and biomechanical applications. The authors conclude that FOS are a promising technology for these applications, but further research is needed to address the remaining challenge.