ColonCAD aids diagnosis

Doctors may be able to diagnose cancers of the colon more accurately and quickly with new Computer Aided Diagnostics (CAD) software from UK-based Medicsight.

The company says recent trials of its software, ColonCAD, showed that radiographers, who are trained to use radiation equipment, detected 100 per cent of cancers when examining 304 patients.

Dr Gareth Beddoe at Medicsight said: 'At the moment CAD is not widely used in clinical practice. CAD for the colon is a relatively new technology. The clinical benefit is that it may help radiologists become more sensitive in reading CT colonography scans.'

A radiologist diagnoses colon cancer by analysing CT scans, searching for protrusions, or polyps, from the colon wall. This could involve looking at 400 to 1,200 images which, depending on the radiologist's expertise, could take from 10 to 40 minutes. Medicsight aims to make its software available to radiologists so they can use data highlighted by the CAD to back up manual readings. 'Currently, standard practice is for the reader to first read the whole case and then switch the CAD on and go through all the results that the CAD has displayed and then make a decision as to whether or not it is a polyp in the colon,' said Beddoe.

The CAD takes between five and 10 minutes to analyse a batch of images of CT scans and alerts radiologists to noteworthy areas by overlaying images with either a circle, dot or square (depending on the workstation).

'The big issue is that they are looking through so many slices of data many times a day,' said Beddoe.

'But the volume of data makes it sometimes quite difficult for them to catch everything — that is really where CAD may have a role in future.'

Anh Nguyen