Off-campus Pacific University users: To download campus access theses and dissertations, please log into our proxy server with your PUNet ID and password.

Non-Pacific University users: Please talk to your librarian about requesting this thesis or dissertation through interlibrary loan.

Theses or dissertations that have a specific embargo period indicated below will not be available to anyone until the date indicated.

Date of Award


Degree Type

Thesis (On-Campus Access Only)

Degree Name

Master of Physical Therapy (MPT)

First Advisor

Richard Rutt, PhD, PT

Second Advisor

Ken Bush, PhD, PT


The purpose of this study was to evaluate the penetration of ultrasound energy through hydrocortisone phonophoresis coupling agents. Penetration through gel and cream bases containing 0%, 1%, and 10% hydrocortisone were tested. Comparisons were also made between 1MHz and 3MHz ultrasound through the same couplants. We evaluated the effects of blending on the coupling bases. The gel was shown to be a much better ultrasound couplant than the cream. The addition of hydrocortisone did affect the transmission characteristics of the couplants, with the greatest effect being seen with the addition of 10% hydrocortisone. We found that 3 MHz ultrasound penetrated through the couplants better than the 1 MHz ultrasound, although the differences were minor. Finally, blending did have a negative impact on the ability of the cream to transmit ultrasound but had almost no effect on the gel.


The digital version of this project is currently unavailable to off-campus users not affiliated with Pacific University; however, it may be accessed on campus or through interlibrary loan (for eligible borrowers) from Pacific University Library. Pacific University Library is a free lender.