The NHS says it will deliver an extra 120,000 scans in the next year following a deal with a private company to supply mobile scanners.
The five-year contract with Alliance Medical Ltd should reduce waits for magnetic resonance imaging scans and help government hit targets.
Staff and 12 mobile scanners, supplied by Alliance Medical Ltd, will tour the country to increase capacity by 15%.
This will add to the 80,000 MRI scans performed currently.
MRI scans use strong magnetic fields that enable doctors to look at internal organs to diagnose a range of medical problems, including cancer, heart disease and epilepsy.
Around the country there have been long waits for MRI, with some people being told they will have to wait up to 12 months for a scan.
Last week, the government promised to cut waiting times for MRI scans as part of its NHS Improvement Plan.
Government hopes the extra capacity will help it meet other targets such as a minimum wait of 18 weeks from GP referral to hospital treatment by 2008.
The mobile scans will cost less than half the equivalent of the NHS price. They will be available to all of England's 28 strategic health authorities on a fair share basis, targeted at areas of greatest need.
London will get two units, while the North West and West Midlands will get three.
Open all week
The new units will start operating from July 22 when they will be open six days a week, from 8am to 8pm Monday to Friday and 8am to 6pm Saturdays.
By November, Alliance Medical Ltd plans to offer a seven day service from 8am to 8pm.
John Hutton said: "This is a great deal for the NHS and its patients.
"It will help reduce the long waits that some patients experience for their MRI scans. By taking the units to those areas with the longest waits, we are prioritising those with the greatest need.
"This is the first instalment of a major expansion in scanning capacity that will come online in the next twelve months," he said.
A spokesman from Alliance Medical Ltd said the company was extremely pleased to have won the contract and was looking forward to working in close partnership with the NHS.
Professor Adrian Dixon from the Royal College of Radiologists said: "Of course it is a good thing to have extra MRI capacity and we welcome anything that reduces patients having to wait."
But he said: "There are a lot of MRI systems in hospitals which have just been put in by the government which are not running to full capacity. We hope it will not interfere with proper funding of these machines."