Ultrasound Machine

Risks and Safety

Part: 1 | 2 | 3 | 4 | 5

Part of the ultrasound machine safety guide....

A further wild card is the variations in sensitivity between fetal tissue and adult tissue: fetal brain tissues are more sensitive to disturbance due to the developmental changes occurring.

The on-screen temperature safety indexes can create misleading confidence, even when being used by fully trained operators. Dr. Abramowicz suggested that the actual amount of tissue heating may exceed the level predicted by the safety index by a factor of 2 to 6. So in actual fact, actual heating may reach a dangerous level even when the safety index shows the levels to be safe.

ultrasound machine

Finally, researchers and ultrasound technologists can’t agree where the “safety baseline” for temperature effects. The majority of researchers regard a temperature rise of 0.5 degrees Centigrade to be safe. However, John Abbott, PhD, director of standards communication for Philips Medical Systems, states that the indexes “cannot be considered as absolute measures of anything. They utilize to the device, transducer and operation condition in use at the time. Also a thermal index of four is quite more than a thermal index of three. That's all.”

Tolerable Levels of Risk with an Ultrasound Machine

Regardless of the uncertainties, doctors continue to use medical ultrasound as the diagnostic benefits are thought to outweigh any potential risk. Dr. Abramowiz states that “The common rationale is that ultrasound has been in use for 45 years now and we haven’t had missing arms and legs.”

To put this in another way, doctors accept that there may be risks, but they believe that medical ultrasound is still a valuable practice when undertaken by a trained operator for diagnostic purposes. According to a Professor of Obstetrics, Gynecology and Pediatrics at Yale University, “It’s impossible to prove ultrasound is completely safe, but if you’re getting medically helpful information, then the tradeoff is reasonable.”

He advises his patients to avoid fetal keepsake portraits, stating “We don’t know what equipment they’re using, what the acoustic output is, and what the training of the personnel is.”
Sonographers limit the duration of medical ultrasound as they realize that tissue heat increases during the length of exposure.

However in multiple investigations of keepsake fetal portrait studios, FDA investigators discovered that patients were being exposed to higher machine settings for up to an hour in order to obtain fetal pictures, much longer than recommended.

Ultrasound Machine and the FDA?

In spite of the FDA’s own findings and concerns, the federal government has recently adopted a much softer stance toward the practice of “keepsake” fetal ultrasound. In the 1990s, when these fetal portrait studios first appeared, the FDA cracked down on them. In fact in 1994, the agency issued warnings to seven such companies to stop making videos or face seizure, injunction, or other regulatory action. Following on from this, in May 1995, five of the companies had shut down.

Even up to 1999, the FDA was still to issuing official warning letters, such as this sample taken from a letter to PK 3D ultrasounds of Coral Springs, Florida: “…to use the UM4A Ultrasound System for non-diagnostic video taping sessions of the fetus for keepsake videography … is in violation of the law.”

The agency has now stopped issuing warning letters, although the number of fetal portrait studios and ultrasound machine usage is rapidly increasing. When queried about this, FDA press officer Sharon Snider responded: “We’re considering what our options are.”

Continue to part five...

Return from Ultrasound Machine to Main Page