you cannot assess because the impact of Xray can happen after 20years
but you have to be careful while using Xray specially in angio and CT select the patient, use non ionic modality if possible and follow the international recommended dose for each scan DRL
I recommend you use RadRat (https://dceg.cancer.gov/tools/risk-assessment/radrat). This is an online tool that uses BEIR VII models and allows estimation of LAR for different organs, patient age etc.