Dr Laura Johnston1
1Nanosonics, Sydney, Australia
Biography:
Laura Johnston BVMS, MBA is the Asia Pacific region Medical Manager for Nanosonics.
Abstract:
Introduction
Ultrasound probes can become contaminated after use and pose an infection risk if not effectively processed. The microscopic surface topography of ultrasound probes may influence the effectiveness of cleaning and high-level disinfection (HLD), yet these features remain poorly characterized.
Methods
This study employed scanning electron microscopy (SEM) to investigate the microscopic topography of ultrasound probe surfaces. Characteristics such as grooves, notches, guide features, orientation markers, and seams, were identified on endocavity (n=4) and surface (n=1) probes. Gaps and crevices within these characteristics were assessed for their potential to harbor microorganisms. Forty-six sites across 15 probe segments were examined using a tungsten-filament SEM under low vacuum at 20 kV.
Results
Of the 46 sites, 32 showed gaps or crevices, with widths of 0.9–480.4 µm. The lens surface revealed microscopically rough texture with crevices as wide as 4.8 µm. Surface wear on an endocavity probe shaft had crevices large enough to shield pathogens. On probe shafts and handles, seam widths of 7.9–480.4 µm containing dried residual contaminants with gaps and crevices were observed. These gaps and crevices are large enough to harbor microorganisms and may interfere with disinfection efficacy.
Conclusions
These findings underscore the importance of considering probe microscopic topography when evaluating HLD methods, as some modalities may have limitations in effectively disinfecting rough, irregular surfaces and features with gaps and crevices. Robust data is essential to determine whether current HLD modalities can effectively disinfect these areas of microscopic complexity across diverse probe types.