Background and aims: CT scan is more used in diagnosis; however, this examined was delivered a low dose estimated approximately to 50 mGy. In this study, the impact of CT scan exposure on hematological parameters for Congo-Brazzaville patients was analyzed. Methods: Blood samples have been obtained from 61 patients including 23 young patients (<17 years). Blood sample was obtained before and 24h after CT-scan exposure from three different hospitals Congo-Brazzaville. 30 healthy donors have been included as a control. Hematological parameters have been analyzed using software. Results: Significant decrease of red blood and hemoglobin were observed after 24 h of CT scan exposure for all patients (p=0.0002 and p=0.0004 respectively). Significant increase of white blood and granulocyte were observed only in adult patients (p=0.0057 and p=0.011 respectively). Significant correlation was observed between the Abdominal-Pleven CT-scan and the variation of white blood and granulocytes. Interestingly, decrease of lymphocytes was observed in adult patients and lymphocyte increase was detected in young patients. Conclusion: We were demonstrated for the first time the variation of hematological parameters after exposure to be very lower doses such as CT-Scan doses. These variations could be reflected inflammatory reactions. Additional analysis can be performed for the validation of these data using a large cohort. Peer Review History: Received: 23 June 2023; Revised: 18 July; Accepted: 25 August, Available online: 15 September 2023 Academic Editor: Prof. Dr. Gorkem Dulger, Duzce University, Turkey, gorkemdulger@yandex.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Sheikh Abdul Khaliq, Department of Pharmacy Practice, Faculty of Pharmacy, Hamdard University, Karachi, Pakistan, drsheikh1974@gmail.com Prof. Hassan A.H. Al-Shamahy, Sana'a University, Yemen, shmahe@yemen.net.ye Ali Jaber, Laboratory for Research and Development of Medicines and Natural Products, RDMPN, Faculty of Pharmacy, Lebanese University, Beirut, Lebanon, ali.jaber.2@ul.edu.lb