Measurement of Patient Radiation Dose in CT Urography and Conventional Urography

Abstract

Radiography has a major role of diagnostic method in medical field. Urography provides the radiologist with useful detailed information. However, it is the responsibility of radiologist and technologist to determine scanning technique factor that provide balance between image quality and radiation dose and share in keeping patient radiation exposure at lowest as possible. The objective of this study are to measure and compare patient radiation dose form computed tomography (CT) and conventional urography and evaluate the protocols used in CTU and IVU imaging procedure. The radiation dose in CTU estimate by using (NRPB) database and using Impact CT patient dosimetry calculator. In IVU the radiation dose determined by calculated using DoseCal software. Patients’ radiation dose values for CTU were 172±61.04 mGy/cm (DLP), CTDIvol 4.75±1.5 mGy and Effective dose 2.58±0.91 mSv. Cancer probabilities per million were 520.12 for pancreas and 30.96 for testicles. Patients radiation dose values for IVU, the mean ESD 21.62±5.85 mGy Effective dose 1.79±0.48 mSv. Cancer probabilities were 962.95 for uterus and 3.45 for thyroid per million. Radiation dose can vary considerably between scanners and between institutions. Clinical dose are reported as the dose to standard dosimetry phantom. However, due to large variation in patient size, these doses may not estimate accurately the dose delivered to patient during a particular exam. In this study the radiation dose is consideredlow compared with previous studies this may be duo the patient size (less than normal), scanner or protocol used. A patient radiation risk for particular exam is proportional to the radiation dose delivered during the exam. This dose will depend on the size of patient, the type of scanner and the imaging protocol used.