The Multidimensional Human Embryo project is a collaboration funded by the National Institute of Child Health and Human Development (NICHD) to produce a complete three-dimensional image reference of the Human Embryo based on magnetic resonance microscopy and to make these images available over the Internet. Each embryo was imaged with three magnetic resonance pulse sequences to obtain fully-registered T1-weighted, T2-weighted, and diffusion-weighted image datasets. The formalin-fixed specimens came from the highly respected Carnegie Collection of Human Embryos. This is the first distributable work to document in three dimensions the anatomy of the human embryonic time period. Pseudo- time-lapse movies were created using morphing software to represent the fourth dimension (time). The project's funding ran from July 1, 1996 through February 2001.
A complete collection of three-dimensional images of human embryology based on MR microscopy was created and organized into a form that is readily distributed. This is the first distributable work to document in three dimensions the anatomy of the human embryonic time period. This was accomplished through the following aims:
1. Acquisition of three-dimensional magnetic resonance data of normal human embryos from stage 10 to stage 23. Each embryo was imaged using three magnetic resonance pulse sequences (T1-weighting, T2-weighting, and diffusion-weighting).
2. Production of a series of images of each embryo in three principal image planes (transverse, coronal, and sagittal), a series of volume-rendered images to represent surface features of each whole embryo, and a series of images to demonstrate time-lapse growth of the human embryo.
3. Organization of the three-dimensional image data into a format that is made available on the Internet.
Disease processes and congenital malformations, as well as normal development, are studied by the effects of gene expression on growth in embryos. The accumulation of gene expression data from non-human mammals and the desire to integrate this information into studies of human development are increasing the demand for access to human embryological data . The need for information on human embryos to better understand processes of development and disease, and the difficulty in obtaining well-documented and well-preserved specimens presents an important challenge to understanding normal and abnormal development. There is a need to minimize the number of embryos of all species used during research and to maximize the distribution of information obtained from the embryos which are used. A complete source of distributable image data representing the human embryological time period is not available. To address these needs we generated a collection of images of human embryology that is interactive and multidimensional. The collection is based on magnetic resonance microscopy of human embryos that were already a part of the highly respected Carnegie Collection of Human Embryos. This interactive collection of digital images goes far beyond any material that is currently available to study human embryology by providing a complete three-dimensional data set for each of 18 human embryos representing Carnegie stages 10 through 23, a critical embryonic time period for organogenesis. The users of the collection are able to manipulate the data on their own personal computers to view any slice from any plane of sectioning. Dynamic rotational views of whole embryos and "time-lapse" views of the growing embryo are accessible. This collection is available to any interested researcher, student, or clinician. It should greatly facilitate the work of clinicians, investigators, and students of human development by bringing diverse pieces of information together in an easily retrievable and widely available form, replacing a process that traditionally takes days or weeks of library research to perform. It preserves a highly respected yet impermanent collection of human embryos and minimizes the need for collecting new embryos. We are a unique source for such a collection because ours is the only research center that combines access to well-documented human embryos, expertise in MR microscopy of embryos, and experience in generating and organizing a collection of digital images of embryos.