The Risks of Overriding X-Ray Safety Features: A Look at Cybersecurity in Medical Devices

It is a common misconception that a radiologist can manipulate X-ray safety features to increase radiation to unsafe levels. In reality, it is the X-ray technician who would have the access and authorization to make such changes. However, should a malicious individual gain unauthorized access, the consequences can be dire, as demonstrated by the tragic case of the Therac-25. This high-level discussion on the topic of medical cybersecurity highlights the potential risks and the importance of robust security measures in medical devices.

Can a Radiologist Override X-Ray Safety Features?

It is not the role of a radiologist to override safety features during an X-ray procedure. They are trained to operate advanced imaging equipment within the prescribed safety guidelines. The X-ray technician, on the other hand, has the professional and ethical responsibility to ensure that all safety precautions are followed. However, if a malicious individual were to gain unauthorized access to an X-ray machine, they could potentially override safety features.

The Case of the Therac-25

The Therac-25 was a medical linear accelerator that served as a radiation therapy machine. It operated with two modes: electron beams and X-ray. Due to a combination of hardware and software flaws, the Therac-25 led to some of the most significant medical disasters ever recorded. One of the safety issues involved was the interaction between the X-ray mode and the electron beam mode.

When the X-ray mode was selected and subsequently switched to the electron beam mode, the software failed to activate the X-ray target. This resulted in the electron beam being inadvertently activated at theoretical 100 times its intended intensity. Since the X-ray target was not in place, the scattering effect would not occur, causing a catastrophic failure of the safety measures. The operators did not realize the severity of the situation until days later when patients began to experience radiation burns. Unfortunately, three patients died as a result of this misconfiguration, highlighting the critical importance of robust security and safety measures in medical devices.

Additional Security Risks

The Therac-25 accident is a stark reminder of the potential dangers posed by software flaws and insufficient hardware safeguards. Another risk associated with medical devices is the possibility of unauthorized access by the operator. For instance, an X-ray technician could potentially manipulate the alignment of the X-ray beam using a field light. If the technician were to activate the accelerator and the light simultaneously, the patient and the technician would be exposed to the X-ray beam while positioning themselves. This scenario poses a significant risk to both the patient and the technician.

Other Forms of Device Tampering

In another example, an X-ray technician could intentionally introduce foreign objects into the MRI machine to cause harm or disruption. Picture a scene in a movie where an X-ray technician is scanning their boyfriend and simultaneously discovering explicit content on his phone. Enticed by humor, the technician might decide to throw a box of thumbtacks and a stapler into the MRI machine, creating a humorous yet dangerous situation in a clinical setting.

Conclusion

The Therac-25 incident serves as a cautionary tale about the risks associated with medical equipment and the necessity for stringent safety protocols. Medical devices, particularly those involved in radiation therapy, must incorporate robust cybersecurity measures to prevent unauthorized access and ensure the safety of both patients and healthcare providers. Beyond technical safeguards, there is a need for ongoing education and training to ensure that all personnel understand the potential consequences of compromising safety features.

As the use of technology in healthcare continues to evolve, the protection of medical devices from cybersecurity threats becomes increasingly important. By learning from historical incidents and implementing comprehensive security measures, the medical community can safeguard against the risks of tampering and malfunctions, ultimately protecting patient care and safety.