The study of local diagnostic reference levels at unit of vascular and interventional radiology, King Chulalongkorn memorial hospital

Abstract

Interventional Radiology (IR) procedures are minimally invasive surgery using angiographic equipment which the patients and staffs may receive high radiation dose. DRLs, based on 75th percentile of the median dose for a sample of standard sized of patients, are an effective tool for optimization of protection in the medical exposure of patients for diagnostic and interventional procedures (ICRP Publication 135, 2017). The objective of this study is to establish the local DRLs distribution of patient radiation dose and related parameters in interventional radiology procedures in standard-sized of Thai patients.

Local DRLs of radiation dose and related parameters of patients (45-75kg for female, and 50-80kg for male) who underwent 3 Neuro-interventional and 9 body interventional procedures were established by retrieving the patient data from PACS and Radimetrics. The data analysis used descriptive statistics via SPSS version 22. The median value of interventional radiology procedures in this study were compared to National DRLs.

The patient data of 485 cases, neuro-intervention 87 cases and body intervention 398 cases, were reviewed and collected between January 2019 and June 2020. The results show that: the median of KAP value and 75th percentile (DRLs) of Cerebral angiogram were 49 and 61 Gy.cm2, Embolization of intracranial aneurysm were 121 and 144 Gy.cm2, Embolization of brain AVM were 157 and 224 Gy.cm2, CT-guided TACE were 287 and 459 Gy.cm2, CBCT-guided TACE were 238 and 397 Gy.cm2, PICC line were 0.7 and 1 Gy.cm2, Perm cath were 1 and 4 Gy.cm2, PCD were 2 and 4 Gy.cm2, PTBD were 6 and 14 Gy.cm2, Peripheral angiogram were 4 and 18 Gy.cm2, Peripheral angioplasty were 7 and 16 Gy.cm2, CBCT-guided Biopsy were 12 and 17 Gy.cm2, respectively. The thickness of the body part, the complexity index, the angiographic equipment, the angiographic materials, the exposure techniques and the interventional radiologists' skill and decision influence the patient radiation dose.

As the patient radiation doses in the therapeutic procedure are always higher than the diagnostic procedures, the DRLs of interventional radiology procedures should be optimized and reviewed DRLs annually. The exposure techniques to decrease the risk of patient radiation dose and reducing scatter radiation to all staffs should be reviewed. The Local DRLs of interventional radiology procedures is established in 2020 while Thailand DRLs is established in 2021. The Local DRLs report is useful in providing a guidance on National DRLs database.