Personnel real time dosimetry in interventional radiology

Real-time dosimetry in interventional radiology - comparing the occupational radiation exposure in fluoroscopy-guided lower extremity and abdominal procedures

OBJECTIVE

Radiation safety concerns have spurred the development of real-time dosimetry systems. This study investigated the occupational dose exposure of interventional radiologists during lower extremity and abdominal procedures.

MATERIALS AND METHODS

Real-time dosimetry was performed during 102 consecutive interventions (51 lower extremity, 51 abdominal). Radiation protection measures included protective glasses (lead equivalent 0.5 mm), thyroid shielding (0.5 mm), vests (0.35 mm), aprons (0.25 mm), as well as movable acrylic and table shields (both 0.5 mm) during all procedures. Dosimeters were attached to the interventionalist's glasses on the side of the x-ray tube, to the back of the supporting hand, and under the vest. Using standardized values over time to account for exposure time differences between interventions, dose-area products and the dose equivalent HP(10) were recorded in all three positions.

RESULTS

Lower extremity angiographies were associated with a substantially lower median dose-area product (5.3 vs. 51.4 Gy × cm2) and exposure time (462 vs. 762 s) than abdominal interventions (both p < 0.001). For lower extremity procedures, HP(10) per minute recorded by the hand, cranium/eye lens, and body trunk dosimeters was 2.45, 0.01, and < 0.01 µSv/min, respectively. Markedly higher dose equivalents were documented for the hand (7.54 µSv/min), cranium/eye lens (0.26 µSv/min), and body trunk (0.04 µSv/min) during abdominal interventions (all p < 0.001).

CONCLUSION

Real-time dosimetry confirmed sufficient radiation protection with the application of dedicated safety measures, even in dose-intensive abdominal procedures. Interventionalists' supporting hands are subjected to the highest radiation exposure, followed by the cranium/eye lens and the body trunk.

KEY POINTS

Question Active dosimetry facilitates real-time assessment of radiation exposure in different measurement sites, but a multi-dosimeter setup has not been explored for interventional radiology so far. Findings Occupational radiation exposure is considerably higher in abdominal than in lower extremity procedures. Interventionalists' supporting hands receive the highest dose equivalents regardless of procedure type. Clinical relevance Dose monitoring in real time is key to understanding the radiation burden of different anatomical features during image-guided interventions. Especially in dose-intensive abdominal procedures, protective measures are essential to minimize the occupational radiation exposure of the interventionalist.

Low dose rate γ-ray detection using a MAPS camera under a neutron radiation environment

We present γ-ray radiation detection in a neutron radiation environment using a monolithic active pixel sensor (MAPS) camera without conversion or shielding layers. The measured output signal is the sum of the pedestal value, noise, and real radiation response signal. The sensor response shows that the MAPS camera is sensitive to neutrons and can capture a single photon. The number of pixels with a signal exceeding 100 exhibits a strong dependence on the dose rate and is the best indicator of this value. Therefore, a MAPS camera can be efficiently used as a radiation detection sensor in a robotic system, further limiting human errors in performing radiation detection in complex nuclear radiation environments.

Ionizing Radiation Measurement Solution in a Hospital Environment

Ionizing radiation is one of the main risks affecting healthcare workers and patients worldwide. Special attention has to be paid to medical staff in the vicinity of radiological equipment or patients undergoing radioisotope procedures. To measure radiation values, traditional area meters are strategically placed in hospitals and personal dosimeters are worn by workers. However, important drawbacks inherent to these systems in terms of cost, detection precision, real time data processing, flexibility, and so on, have been detected and carefully detailed. To overcome these inconveniences, a low cost, open-source, portable radiation measurement system is proposed. The goal is to deploy devices integrating a commercial Geiger-Muller (GM) detector to capture radiation doses in real time and to wirelessly dispatch them to a remote database where the radiation values are stored. Medical staff will be able to check the accumulated doses first hand, as well as other statistics related to radiation by means of a smartphone application. Finally, the device is certified by an accredited calibration center, to later validate the entire system in a hospital environment.