2021
Dr. Ryan Lilien
Miami, FL
“3D Virtual Comparison Microscopy is a powerful tool for microscopic examination which presents an examiner with a highly detailed visualization of a toolmark surface. VCM can provide a number of advantages of LCM in the areas of access, speed, documentation, and quality. For example, after evidence and test fires are scanned at a 3D microscope, the topography data may be viewed down the hall or off-site on a second computer where examiners can annotate the surfaces, link items with common source, capture screenshots, record tesxt notes, and export structured case notes for inclusion in LIMS. Several recent studies, such as our VCM Error Rate Study (VCMERS) and our VCM Topography Resolution Study (VCMTRS) each involving over 100 participants, provide strong support for the qualify of VCM examination. These studies establish 3D Virtual Comparison Microscopy as a viable alternative to traditional light comparison microscopy within the discipline of firearm examination. As labs begin to incorporate VCM into their standard operations, many have questions about what is possible and how the technology can be implemented.
In this presentation, through screenshots and examples, we will review the uses of VCM within a lab, covering such topics as hardware and software validation, 3D visualization, establishing common source, documenting conclusions, recording electronic notes, exporting notes and images for LIMS integration, conducting blind verification, sharing data among multiple sites, and enabling remote access. We will also review the use of software for specimen triage, database search, and blind verification. Finally, we will discuss the state of comparison algorithms, scoring, and statisitics.
Labs moving to incorporate VCM do not need to implement all presented uses. Some labs may only use VCM for triage or for remote (off-site) access while others will use VCM through their entire examination pipeline from intake through report generation and verification. “