Exploring Mobile DR: The “Moving Robot” in Hospitals

 In hospitals, many people have probably noticed medical staff pushing a mobile “robot” through hallways and wards. Out of curiosity, you may have wondered—what exactly is this machine? What is it used for? What are its advantages and disadvantages?

Today, let’s take a closer look at the mobile DR (Digital Radiography) system.

What Is a Mobile DR System?

A mobile DR, or mobile digital radiography system, is a portable X-ray imaging device that allows radiologic examinations to be performed directly at the patient’s bedside.

Key Advantages of Mobile DR

1. Overcoming Spatial Limitations

Mobile DR enables bedside imaging without the need to transfer critically ill patients, reducing the risks associated with patient transport—such as tracheal tube displacement or interference with ECMO (extracorporeal membrane oxygenation) equipment.
It is particularly useful in ICUs, emergency departments, and for postoperative patients who cannot be moved easily.

2. Immediate Diagnostic Support

Mobile DR allows rapid image acquisition and transmission, shortening examination times and providing immediate diagnostic evidence for acute conditions such as ARDS (acute respiratory distress syndrome) and traumatic pneumothorax, thereby supporting faster clinical decision-making.

3. Excellent Portability

Compact in structure and lightweight, the system is typically equipped with dual-motor drive, zero-radius turning, and power-assisted movement, allowing it to pass through narrow spaces such as doorways or staircases with ease.
Instead of “patients going to the device,” the device goes to the patients, making imaging examinations far more convenient.

Limitations of Mobile DR

1. Equipment Parameter Constraints

Compared to stationary DR systems, mobile DR units generally have lower tube voltage, tube current, and detector resolution, which can result in insufficient image contrast and detail visibility.

2. Limited Examination Range

Since most mobile DR units lack a grid component, imaging quality may decline when examining thicker anatomical regions. In addition, bedside conditions—such as uneven or unstable patient beds—may cause image distortion, affecting diagnostic accuracy.
At present, mobile DR systems are also unable to perform long-length or stitched imaging.

3. Radiation Exposure Concerns

Unlike radiology departments, general wards lack proper lead shielding. As a result, other patients and medical staff in the same room may experience low-dose radiation exposure during bedside imaging.

Therefore, bedside X-ray imaging should not replace standard radiographic examinations. It serves as a supplementary diagnostic tool in emergency situations, providing quick clinical information and convenience for patient care.
When bedside imaging is required, unrelated individuals nearby should avoid staying in the area to minimize unnecessary radiation exposure.

Radiology Department’s Friendly Reminders

1. Cooperation Improves Efficiency

During bedside imaging, if the patient is conscious, please follow the technologist’s instructions carefully—hold your breath or remain still at the moment of exposure (for example, deep inhalation for chest X-rays).
If the patient is unconscious, the medical staff will assist with positioning to ensure image clarity and reduce the need for repeat exams.

2. Appropriate Clinical Indications

Bedside imaging should be reserved for critically ill patients, such as:

• Orthopedic patients under traction
• Emergency or trauma patients who cannot be safely moved
• Patients requiring absolute bed rest

For patients who can move, it is best to perform X-ray exams in the radiology department to ensure higher image quality and diagnostic accuracy.

3. Understand Radiation Scientifically

A single bedside X-ray results in a radiation dose of about 0.02 mSv—approximately equivalent to three days of natural background radiation, and far below the annual public dose limit of 1 mSv.
There is no need for excessive worry, but when bedside imaging is necessary, reasonable protection should be provided for patients, family members, and medical personnel.