Objectives: To assess the changes in levator ani mus- cle (LA) function by measuring the velocity, displacement and strain during a valsalva using tissue Doppler imaging in the first and third trimesters compared to one year postpartum. Methods: This is a prospective study of serial trans- perineal imaging of the LA in 31 primigravid subjects during the first and third trimesters of pregnancy and one year post- partum. Strain data was obtained using tissue Doppler imaging in the mid-sagittal plane of the pelvic floor at the level of the le- vator hiatus, recorded during maximal valsalva. The mean ve- locities, displacements, strains and strain rates were determined by post processing using Qlab version 8.1 (Philips, Andover MA). Results: The findings in pregnancy and the post- partum are summarized in table 1. There was a statistically sig- nificant increase in the velocity, displacement and the strain rate from the first to third trimester (student t-test p values 0.001, 0.003 and 0.03, respectively) with a return to first trimester levels by 1 year postpartum (All p values.0.05). Conclusions: The velocity, displacement and strain rate of the LA during a valsalva increase as pregnancy pro- gresses then returns to first trimester levels postpartum. These findings suggest that the LA relaxes as pregnancy progresses and increases in mobility. These changes most likely represent maternal adaptations of the pelvic floor for eventual vaginal de- livery. After delivery these pregnancy related changes resolve. Larger prospective studies are needed to further evaluate the role of these changes in pregnancy and the consequences of mal- adaptation. 2089671 Evaluation Of The Clinical Efficacy Of An Automated, Hydrogen Peroxide-Based Device For The High Level Disinfection Of Ultrasound Probes Robert DeJong Radiology Ultrasound, the Johns Hopkins Hospital, Baltimore, MD, United States Objectives: Ultrasound probes that contact mucous membranes or non-intact skin are considered semi-critical items requiring high level disinfection (HLD) between patients. HLD has typically involved soaking in glutaraldehyde or ortho-phtha- laldehyde, however a new automated HLD device using nebu- lized hydrogen peroxide is now available. This study assessed the efficacy of this device against surface and intracavity probes in a clinical setting. Methods: Probes were randomly sampled from two groups; either following cleaning or following HLD with the automated disinfection device (trophonÒ EPR). Surface probes and heads and handles of intracavity probes were sampled along with controls to monitor sampling contamination. Contamina- tion levels were assessed using aerobic bacterial plate counts and predominant isolates were identified using 16S rRNA sequencing. Results: All groups showed bacterial contamination prior to disinfection: surface probes [median 10 CFU, interquar- tile range (IQR) 0-65]; intracavity heads [median 0 CFU, IQR 0- 10]; intracavity handles [median 170 CFU, IQR 10-290]. In all cases, disinfection in the device produced a statistically signif- icant reduction in contaminants: surface probes [median 0 CFU, IQR 0-10]; intracavity heads [median 0 CFU, IQR 0- 0]; intracavity handles [median 0 CFU, IQR 0-0]) with post- disinfection contamination levels reduced to the level of the sampling control. While most organisms were typical environmental and skin flora, pathogens including Dermabacter hominis, an occasional cause of fatal bacteremia and Coryne- bacterium aurimucosum, an organism occasionally associated with spontaneous abortion were also isolated prior to disinfection. Conclusions: The extent of contamination demon- strates the need for HLD to reduce transmission risks. As some recommendations for surface probes only involve clean- ing but not disinfection, risks posed by residual organisms may need to be reviewed. Handles of intracavity probes were the most contaminated, underscoring the need to disin- fect both the probe head and handle. In all cases, the auto- mated device successfully reduced contamination to background levels. High Frequency Clinical and Preclinical Ultrasound Moderators: Flemming Forsberg, PhD, Ximena Wortsman, MD 2091785 Development Of A Small Animal Model Of Onchocerciasis: Verification With High-Frequency Ultrasound Imaging Maria Stanczak, 1 Jessica A. Hess, 2 John B. Patton, 2 John R. Eisenbrey, 1 Ji-bin Liu, 1 April Torigian, 2 David Abraham, 2 Flemming Forsberg 1 1 Radiology, Thomas jefferson University, Philadelphia, Pennsylvania, United States; 2 Microbiology and Immunology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States Objectives: Onchocerciasis (river blindness) affects millions of people mainly in Sub-Saharan Africa and is caused by the parasitic worm Onchocerca volvulus. A murine model Table 1. Mean velocity, displacement, strain and strain rate in pregnancy and postpartum Mean Gestational Age & Post partum (weeks) Mean Velocity (cm/sec) +/- 1 SD Mean Displacement (mm) +/- 1 SD Mean Strain (1/sec) +/- 1 SD Mean Strain Rate (%)+/- 1 SD 13.0 0.71 +/- 0.58 2.1 +/- 1.3 6.4 +/- 4.7 0.16 +/- 0.09 31.2 1.16+/-0.67 4.0+/-2.4 9.0+/-8.5 0.22+/-0.16 50.0 0.84 +/-0.43 3.2+/-2.3 6.1+/-7.3 0.16+/-0.15 S12 Ultrasound in Medicine and Biology Volume 41, Number 4S, 2015