Researchers develop software to image tissue in 3-D

Computer scientists and medical researchers at the University of Leeds (Leeds, UK) have developed a way of studying tissue samples using a digital scanning system that produces high-resolution, multi-colored 3-D images that can be rotated and examined from any angle.

At the moment, hospital pathologists and medical researchers cut tissue samples into thin slices and examine these by hand, one-by-one, on a microscope. This is a labour-intensive process - a single slide can contain several hundred thousand cells - and the number of slices examined will be limited by the time available. To perform a true 3-D analysis, users would need to look at 100s of different 2-D sections - something that would be prohibitively expensive by hand.

In contrast, the system developed at Leeds requires almost no extra manual input once the tissue has been cut and mounted onto glass slides. An automated system turns batches of the slides into high-resolution digital images, which are then aligned using image registration software. Users can then study these virtual blocks of tissue in 3-D and zoom in on particular areas of interest.

The researchers have now tested the system on eight different types of tissue, using more than 13000 virtual slides to create around 400 separate 3-D volumes.

"Up until now, the use of 3-D imaging technology to study disease has been limited because of low resolution, and the time and difficulty associated with acquiring large numbers of images with a microscope," says lead investigator Dr. Darren Treanor, pathologist at the University of Leeds and the Leeds Teaching Hospitals NHS Trust.

"Our virtual system means that users can look at the shape and structure of cells and the 'micro-architecture' of blood vessels and tumors on large tissue samples. This can all be done without input from computing specialists."

"Having a 3-D view can often make a real difference," says Dr Derek Magee, from the University of Leeds' School of Computing who developed the software behind the system. "For instance, if you want to understand how a system of blood vessels supplying a tumor connects up, you really need to see that in 3-D, not as a series of separate 2-D sections."

The work was funded by the National Cancer Research Institute informatics initiative, Leeds Teaching Hospital Trust Research and Development, National Institute for Health Research, West Yorkshire Comprehensive Local Research Network, the UK Department of Health, and the Wellcome Trust.

-- by Dave Wilson, Senior Editor, Vision Systems Design