Author(s)

Norihiko Akiba, Masashi Takeda, Giichiro Nakaya, Osamu Nakamura, Joel Matsumoto, Kyoichi Ito, Morio Shimada, Kohki Yoshikawa

Department of Clinical Engineering, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.
Department of Radiological Technology, Nihon Institute of Medical Science, Moroyama, Japan.
Department of Radiology, Japanese Red Cross Medical Center, Tokyo, Japan.
Department of Radiology, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.
Graduate Division of Medical Health Sciences in Graduate School of Komazawa University, Tokyo, Japan.

We conducted experiments of oversensing generation of pacemaker (PM) and X-irradiation direction dependency of PM, and examined the oversensing suppression method, using 8 different types of PMs. It was found out from this experiment that oversensing would occur when some conditions (X-irradiation direction, X-irradiation intensity) are met. Oversensing occurred with the most low irradiation conditions (kV × mA) when PM was irradiated at 90° (vertically to C-MOS; Complementary Metal Oxide Semiconductor). The acuter the angle of irradiation is (α > 90° < α), the higher the irradiation conditions (kV × mA) at which oversensing start to occur. In plain X-ray photography, oversensing was confirmed under the irradiation conditions of (cervical spine, thoracic spine, lateral thoracic spine, rib, shoulder joint, collarbone, humerus, and chest).Once the irradiation angle and irradiation conditions (kV × mA) are available, oversensing is predictable to some extent. Our findings will help to predict oversensing generation of plain X-ray photography and suppress oversensing. Oversensing can be suppressed in most of the radiography by lowering tube current to 100 mA, but a 1.0 mm High-Density Tungsten Sheet must be put on PM in high tube voltage radiography.

Oversensing; Pacemaker; C-MOS; General X-Ray Equipment for Diagnosis

N. Akiba, M. Takeda, G. Nakaya, O. Nakamura, J. Matsumoto, K. Ito, M. Shimada and K. Yoshikawa, "Predicting and Suppressing Oversensing of a Pacemaker in Plain X-Ray Photography," Open Journal of Radiology, Vol. 2 No. 4, 2012, pp. 128-133. doi: 10.4236/ojrad.2012.24024.