Open AccessIntense Focused Ultrasound Preferentially Stimulates Subcutaneous and Focal Neuropathic Tissue: Preliminary Results
Author(s) -
McClintic Abbi M.,
Dickey Trevor C.,
Gofeld Michael,
Kliot Michel,
Loeser John D.,
Richebe Philippe,
Mourad Pierre D.
Publication year - 2013
Publication title -
pain medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.893
H-Index - 97
eISSN - 1526-4637
pISSN - 1526-2375
DOI - 10.1111/j.1526-4637.2012.01510.x
Subject(s) - neuroma , medicine , ultrasound , stimulation , subcutaneous tissue , soft tissue , therapeutic ultrasound , radiology , pathology , surgery
Objective. Potential peripheral sources of pain from subcutaneous tissue can require invasive evocative tests for their localization and assessment. Here, we describe studies whose ultimate goal is development of a noninvasive evocative test for subcutaneous, painful tissue. Design. We used a rat model of a focal and subcutaneous neuroma to test the hypothesis that intense focused ultrasound can differentiate focal and subcutaneous neuropathic tissue from control tissue. To do so, we first applied intense focused ultrasound (2 MHz , with individual pulses of 0.1 second in duration) to the rat's neuroma while the rat was under light anesthesia. We started with low values of intensity, which we increased until intense focused ultrasound stimulation caused the rat to reliably flick its paw. We then applied that same intense focused ultrasound protocol to control tissue away from the neuroma and assayed for the rat's response to that stimulation. Results. Intense focused ultrasound of sufficient strength (I SATA of 600 +/− 160 W/cm 2 ) applied to the neuroma caused the rat to flick its paw, while the same intense focused ultrasound applied millimeters to a centimeter away failed to induce a paw flick. Conclusion. Successful stimulation of the neuroma by intense focused ultrasound required colocalization of the neuroma and intense focused ultrasound supporting our hypothesis.