Smart sensor for guiding safe delivery of anesthetic and pain drugs through epidurals

Project Summary/AbstractPhysical Sciences Inc. (PSI) proposes to develop a novel approach for guiding safer delivery of pain and/or anesthetic drugs during epidural procedures (EPs). Epidural injections are typically used to treat pain from herniated discs, spinal stenosis, chemical discs, chronic pain secondary to post-cervical surgery syndrome, and chronic neck pain of discogenic origin. They are also regularly used to alleviate pain related to birth. However, when not properly performed, the epidural injections can have negative side effects, such as severe headache, infection, and even nerve damage. Serious side effects may also occur, including stroke, paralysis, or loss of vision.This proposal aims to overcome current issues related to epidural injections by using a novel and more reliable low coherence interferometry (LCI) optical sensing approach to determine what tissue type is present at the tip of the needle, while monitoring the force applied to the needle to safely pass it into the epidural space using a fiber Bragg sensor.During the Phase I effort PSSI has developed a laboratory prototype for epidural guidance that combines low coherence interferometry with Bragg sensing within the same probe. This approach was tested and optimized ex vivo on animal tissue specimens. Although feasibility was demonstrated, the differentiation of tissue types was somewhat impeded by the relatively high intensity noise of the light source owed by PSI and used in the experiments. Therefore, we request NIH support to purchase a better performing light source, as well as to cover the nonrecurring engineering cost of suitable Bragg gratings that better match the spectral characteristics of this light source. After improving the setup, the technology will be evaluated in live animals. Based on the Phase I findings, the technology will be further improved during Phase II and validated on humans at BWH.