RSNA: iPads/iPhones not quite ready for prime time
Mobile devices may work well for consultation, but are too small to be used for routine primary diagnosis. Security and calibration issues remain unsettled, and the FDA has not yet decided how to handle these devices, David Hirschorn, MD, said Nov. 29 during a presentation at the 96th annual meeting of the Radiological Society of North America (RSNA).
“The government doesn’t like change too much or too fast, but consumers and the business world say ‘heck if the technology is there I’m going to use it.'" However, outstanding questions such as where, when and how this technology should be used, remain unanswered.
“There is a lot of potential in this technology but you want to use it to help patients, not hurt them,” said Hirschorn, director of radiology informatics at the Staten Island University Hospital in Staten Island, N.Y.
Because the iPhone and iTouch are net-enabled, “there is a world of potential for their use. But, how do you know whether your device is operating within the correct parameters and that it is OK to use?" Hirschorn asked.
“In January 2010, the FDA said ‘wait a second.' The FDA’s Center for Devices and Radiological Health (CDRH) said that a vendor's iPhone imaging viewing and multimodality fusion software was not “substantially equivalent to predicate devices, based on its new proposed indication for displaying medical images for diagnostic use on a mobile/portable device," said Hirschorn.
In addition, the agency said that the mobile devices raise safety and effectiveness questions and must undergo a more in depth premarket approval (PMA) process in order to gain market clearance to be used effectively for diagnostic purposes.
“Bottom line—they [the FDA] were afraid,” said Hirschorn. “We didn’t get our PACS operations recertified every time Intel came out with a new processor or a vendor came out with a new display, but the iPhone came out and now the FDA says ‘this is not substantial equipment.’”
Hirschorn did emphasize that it is essential to assess whether or not physicians are hurting patients by diagnosing images with these devices, and said that the iPhone may be too small to do so.
One of the biggest issues regarding the use of iPads and iPhones to view medical images is brightness and luminance level. “We have to see 256-shades of gray,” said Hirschorn. These shades cannot be compressed, as 256-shades of gray are necessary to make a medical diagnosis.
And while the iPad meets the American College of Radiology minimum for luminance level, medical CRTs are much higher. Medically marketed displays hold luminance stability and can last five years or more, consumer-based LCD’s “decay steadily,” said Hirschorn.
Proper calibration is another issue that must be undertaken. “Calibration is like tuning a musical instrument,” said Hirschorn. “I don’t care how much money you spent on your violin, just because you spent money and it’s a high quality device does not mean it’s going to stay in tune for years. Things happen … humidity, weather changes … things drift and displays drift too.”
Medically marketed displays are finely tuned to luminance value, and manual maintenance is still required, but consumer displays must be calibrated to meet DICOM Part 14 Grayscale Display Function standards.
“You can’t lose the contrast of images … you must ensure that the device stays within the operating parameters. Anyone who has glasses knows that you don’t just get a prescription and use it for the rest of your life.”
The mobile devices must be checked on a semi-annual basis to ensure that they adhere to DICOM curve conformance.
To appropriately diagnose a chest x-ray or bone work, a display screen size of 20 inches is necessary. “Anything less than that [is] like a postage stamp,” says Hirschorn. “There is just not enough real estate to work with.” The iPod is only 3.5 inches, while the iPad is 9.7 inches, not significant enough in size to ensure a proper clinical diagnosis, he noted.
Calibration and security issues remain unsolved and a test pattern will be necessary to show auditors and the government that the display device within this technology meets normal operating parameters.
“Mobile devices are too small for routine primary diagnosis certainly for CR and probably to some degree for CT. If you want to really read out a CT scan it’s going to be tough. The iPhone and iPad may not be enough to get a primary diagnosis,” Hirschorn concluded.
“But, for consultation and even primary diagnosis, on a limited basis, these devices may work fine,” he said. “However, the FDA has yet to decide.”
“The government doesn’t like change too much or too fast, but consumers and the business world say ‘heck if the technology is there I’m going to use it.'" However, outstanding questions such as where, when and how this technology should be used, remain unanswered.
“There is a lot of potential in this technology but you want to use it to help patients, not hurt them,” said Hirschorn, director of radiology informatics at the Staten Island University Hospital in Staten Island, N.Y.
Because the iPhone and iTouch are net-enabled, “there is a world of potential for their use. But, how do you know whether your device is operating within the correct parameters and that it is OK to use?" Hirschorn asked.
“In January 2010, the FDA said ‘wait a second.' The FDA’s Center for Devices and Radiological Health (CDRH) said that a vendor's iPhone imaging viewing and multimodality fusion software was not “substantially equivalent to predicate devices, based on its new proposed indication for displaying medical images for diagnostic use on a mobile/portable device," said Hirschorn.
In addition, the agency said that the mobile devices raise safety and effectiveness questions and must undergo a more in depth premarket approval (PMA) process in order to gain market clearance to be used effectively for diagnostic purposes.
“Bottom line—they [the FDA] were afraid,” said Hirschorn. “We didn’t get our PACS operations recertified every time Intel came out with a new processor or a vendor came out with a new display, but the iPhone came out and now the FDA says ‘this is not substantial equipment.’”
Hirschorn did emphasize that it is essential to assess whether or not physicians are hurting patients by diagnosing images with these devices, and said that the iPhone may be too small to do so.
One of the biggest issues regarding the use of iPads and iPhones to view medical images is brightness and luminance level. “We have to see 256-shades of gray,” said Hirschorn. These shades cannot be compressed, as 256-shades of gray are necessary to make a medical diagnosis.
And while the iPad meets the American College of Radiology minimum for luminance level, medical CRTs are much higher. Medically marketed displays hold luminance stability and can last five years or more, consumer-based LCD’s “decay steadily,” said Hirschorn.
Proper calibration is another issue that must be undertaken. “Calibration is like tuning a musical instrument,” said Hirschorn. “I don’t care how much money you spent on your violin, just because you spent money and it’s a high quality device does not mean it’s going to stay in tune for years. Things happen … humidity, weather changes … things drift and displays drift too.”
Medically marketed displays are finely tuned to luminance value, and manual maintenance is still required, but consumer displays must be calibrated to meet DICOM Part 14 Grayscale Display Function standards.
“You can’t lose the contrast of images … you must ensure that the device stays within the operating parameters. Anyone who has glasses knows that you don’t just get a prescription and use it for the rest of your life.”
The mobile devices must be checked on a semi-annual basis to ensure that they adhere to DICOM curve conformance.
To appropriately diagnose a chest x-ray or bone work, a display screen size of 20 inches is necessary. “Anything less than that [is] like a postage stamp,” says Hirschorn. “There is just not enough real estate to work with.” The iPod is only 3.5 inches, while the iPad is 9.7 inches, not significant enough in size to ensure a proper clinical diagnosis, he noted.
Calibration and security issues remain unsolved and a test pattern will be necessary to show auditors and the government that the display device within this technology meets normal operating parameters.
“Mobile devices are too small for routine primary diagnosis certainly for CR and probably to some degree for CT. If you want to really read out a CT scan it’s going to be tough. The iPhone and iPad may not be enough to get a primary diagnosis,” Hirschorn concluded.
“But, for consultation and even primary diagnosis, on a limited basis, these devices may work fine,” he said. “However, the FDA has yet to decide.”