Automated determination of chest characteristics of Indonesians as the basis of chest dosimetrical phantom design

Abstract Purpose: The purpose of this study was to develop software to automatically measure the main areas of the chest, i.e. soft tissue, bone, and air and to implement it in Kraton Regional General Hospital for designing a specific dosimetrical phantom for chest digital radiography (DR) examination. Methods: This study was a retrospective study on all DR images from 2015 to 2019, and computed tomography (CT) images of 102 patients in Digital Imaging and Communications in Medicine (DICOM) format files scanned from January-December 2019 at the Kraton Regional General Hospital. We evaluated the number of basic DR chest examinations compared to all DR radiological examinations. We developed a MatLab graphical user interface (GUI) for automated measurement of the areas of the main chest components (soft tissue, bone, and air). We computed the areas of the main components of the chest in order to develop a specific chest phantom for DR in the hospital. In order to compute the areas of the main components, we used chest CT images of patients with clinical indications of chest tumors. Results: The basic DR chest examination comprised 59.5% of all DR examinations in the hospital during 2015-2019. The average areas of soft tissue, bone, and air within the chest in all patients were 331, 20, and 125 cm2, respectively, with values of 345, 23, and 139 cm2 for males, and 309, 15, and 103 cm2 for females. The areas were also dependent on age with values of 121, 10, 55 cm2 for patients aged 5-11 years, 371, 27, and 88 cm2 for patients aged 12-25 years, 322, 22, and 131 cm2 for patients aged 26-45 years, and 334, 19, and 126 cm2 for patients > 45 years old. Conclusion: A GUI for computing the main composition of the chest was successfully developed. The areas of chest male patients were greater than female patients. The areas of soft tissue, bone, and air were dependent on the patient’s age. Therefore, the design of dosimetrical DR phantom must consider the gender and age of the patient.