Performance of CMOS imager as sensing element for a Real-time Active Pixel Dosimeter for Interventional Radiology procedures

Abstract

Staff members applying Interventional Radiology procedures are exposed to ionizing radiation, which can induce detrimental effects to the human body, and requires an improvement of radiation protection. This paper is focused on the study of the sensor element for a wireless real-time dosimeter to be worn by the medical staff during the interventional radiology procedures, in the framework of the Real-Time Active PIxel Dosimetry (RAPID) INFN project. We characterize a CMOS imager to be used as detection element for the photons scattered by the patient body. The CMOS imager has been first characterized in laboratory using fluorescence X-ray sources, then a PMMA phantom has been used to diffuse the X-ray photons from an angiography system. Different operating conditions have been used to test the detector response in realistic situations, by varying the X-ray tube parameters (continuous/pulsed mode, tube voltage and current, pulse parameters), the sensor parameters (gain, integration time) and the relative distance between sensor and phantom. The sensor response has been compared with measurements performed using passive dosimeters (TLD) and also with a certified beam, in an accredited calibration centre, in order to obtain an absolute calibration. The results are very encouraging, with dose and dose rate measurement uncertainties below the 10% level even for the most demanding Interventional Radiology protocols.

Simultaneous measurement of ionizing radiation and heart rate using a smartphone camera

“…In recent years, complementary metal oxide semiconductor (CMOS) cameras have been used for X/γ-ray detection and classification [11][12][13][14]. This promising direction has advantages of higher penetration rate and lower cost compared to traditional methods.…”

“…This promising direction has advantages of higher penetration rate and lower cost compared to traditional methods. Studies have shown that random bright spots are generated in images recorded by CMOS image sensors under irradiation of X/γ rays [11][12][13]. Xu et al studied the potential of CMOS image sensors and found that both the mean pixel value and the cumulative pixel value have a linear relationship with radiation dose rate [14][15][16].…”

Radiation Dose Rate Measurement for Protection Programs in the Work Environment for the Health Workers: An Experimental Study

“…The radiation dosimeters are divided into two groups, in the aspect of reading, including (1) the passive types, comprising measurement results, which is difficult to read directly. Hence, there is a need for initial special processing (Knoll, 2007), including film badge and thermoluminescent dosimeter (TLD) (Magalotti et al, 2014). Medical personnel within the area of interventional radiology (IVR) are at risk of exposure to high doses of scattered radiation emitted from the patient (Fujibuchi et al, 2019).…”