Assessment of Contrast Media Volume Injected and Image Contrast in Abdominal Pelvic CT Scan and Related Factors in Referral Hospitals in Mazandaran, Iran

 Background and purpose: Computed tomography scan (CT) is highly capable of diagnosing abdominal and pelvic lesions. Injection of contrast media at appropriate concentration and volume provides the least side effects and the highest image quality. This study aimed at investigating the volume of contrast medium injected and the level of image contrast compared to the standard model, in the imaging department of referral hospitals in Mazandaran province, Iran. Materials and methods: In this quantitative descriptive study, CT scan imaging protocols in abdominal examinations and physical characteristics of the patients were recorded The difference in the volume injected of contrast media were compared between conventional method and standard method. Several CT scan images with different contrast levels were divided into four image quality groups by two experienced radiologists based on the ratio of contrast to image noise (CNR) of the organs. The percentage of adherence of the centers to the standard method and the percentage of each image quality group was calculated using descriptive statistics. Results: The CT scan imaging centers showed low adherence (37%) to the standard method (weight-based injection). Among the images investigated, 51.6% had excellent and good contrast levels. There was no correlation between patients’ weight and the volume of contrast medium injected (P<0.05). The CNR of the organs increased as the amount of iodine injected per unit mass increased.  Conclusion: Imaging centers should select the volume of the contrast medium based on patientchr('39')s weight. The image quality is a function of the amount of iodine injected per unit weight of the patient, therefore, the concentration of contrast agent must be correctly selected.