A four-dimensional digital image archiving system for cell lineage tracing and retrospective embryology

The paper describes a digital image archiving system for time-lapse microscopy. The system uses an MS-DOS compatible computer to store video images while simultaneously controlling a stepping motor. In a typical experiment, images might be taken at 30 s intervals in each of 25 consecutive focal planes. A system with 2.5 Gbyte disk capacity can store approximately 18,000 full frame images: 6 h recording at maximum resolution. Once recorded, images series stored on disk can be 'played back' in any order. Generally, images from a single focal plane are displayed consecutively in either forward or reverse time. The focal plane can be shifted during playback, allowing individual cells to be followed as they move between focal planes. To facilitate the annotation and interpretation of the real-time images, a mouse-driven interface allows users to define and follow individual objects (e.g. cells). The recorded image series can be achieved inexpensively using standard digital tape backup hardware. In this laboratory, the system has been particularly useful for tracing embryonic cell lineages and cell migrations. Detailed system specifications, including source code, compiled programs, hardware requirements and users manual are available directly from the author or by anonymous FTP (ciw1.ciwemb.edu).