If your facility is considering an upgrade from a Selenia Dimensions to a 3Dimensions system — or if you already operate both — understanding the engineering differences between these platforms is valuable context for service planning and parts management.
Shared Foundation, Different Engineering
The 3Dimensions system evolved from the Selenia Dimensions platform, and the two share many components: the basic gantry architecture, much of the power distribution system, and the general mechanical framework. However, Hologic made significant changes to the 3Dimensions that affect service requirements.
Key Differences That Affect Service
The most significant changes in the 3Dimensions include: a redesigned tubehead and collimator assembly optimized for 3D acquisition; updated compression device assembly (CDA) with the SmartCurve paddle system including paddles like the 18x24 Smart Curve (ASY-11738); new gantry covers specific to the Genius 3D branding; revised internal compression assembly; and updated C-arm components.
From a parts perspective, many components carry both SDM (Selenia Dimensions Mammography) and 3DM (3Dimensions Mammography) part numbers. For example, the external compression device assembly is ASY-12206 for SDM and ASY-14853 for 3DM. These are not interchangeable — using the wrong part number can result in fit issues or functionality problems.
Service Interval Considerations
While both systems follow similar PM protocols, the 3Dimensions system's additional complexity — particularly the 3D acquisition components and SmartCurve technology — means that PM visits may require additional time and specialized calibration procedures.
Parts Inventory Planning
If your facility operates both Dimensions and 3Dimensions systems, be aware that parts commonality is lower than you might expect. While many power distribution, electrical, and basic mechanical components are shared, anything related to the tubehead, compression system, covers, or 3D-specific functionality will require platform-specific parts.
Working with MammoService
MammoService maintains separate parts inventories for both SDM and 3DM components and our engineers are trained on both platforms. Whether you're running a legacy Dimensions system or the latest 3Dimensions, we have the expertise and parts to keep your equipment running.