Optimization of patient dose in abdominal computerized tomography

الملخص EN

Abdominal computed tomography (CT) scan have contributed greatly to diagnose abdomen diseases.

However the radiation exposure to the patient is significantly higher in respect to other radiological examinations.

While the benefits of CT exceed the potential effects of radiation exposure to patients, increasing radiation doses to the population have raised a compelling case for reduction of radiation exposure from CT.

In Sudan, there was a remarkable increase of CT examinations being performed.

Therefore, radiation dose optimization is mandatory because of the risks associated with exposure to radiation.

The purpose of this study was to optimize the radiation dose, estimate the effective dose and radiation risk during adult computed tomographic (CT) for abdomen.

A total of 83 patients referred to The National Ribat University Hospital (NRUH) in the period of the study with abdominal disturbances.

Data of the technical parameters used in CT procedures was taken during May - October, 2009.

The patients were divided into two groups: Control group (53patients) were examined with the own department protocol using multislice CT (MSCT) 16 slice (Siemens Sensation); and optimization group (30 patients).

Optimization was achieved through; the design of dose efficient equipment, the optimization of scan protocol and improvement of referring criteria.

Organ and surface dose to specific radiosensitive organs was estimated by using software from National Radiological Protection Board (NRPB).

The mean age was 45.4±18 years while the mean weight was 67±14Kg.

The DLP was 288.25 mGy.cm and CTDIvol was 9.7 mGy.

Patient effective doses were 13.5 mSv before the optimization.

Conversely, this was reduced to 4.3 mSv after dose optimization.

Estimated radiation risk is 742 x10-6 conversely the risk was reduced to 237 x10-6.

Dose optimized protocol lowered the effective doses to 31.9%.

KEYWORDS: Radiation risk, Radiation dosimetry