Keywords:
Ischaemia / Infarction, Dosimetric comparison, Biological effects, Radiation effects, Catheters, Arterial access, Percutaneous, Fluoroscopy, Catheter arteriography, Radioprotection / Radiation dose, Cardiovascular system, Cardiac
Authors:
T. Heary, R. Faulkner; DUBLIN/IE
DOI:
10.26044/ecr2019/C-2620
Methods and materials
Radiation dose metric data for 880 PCI studies (197 females and 683 males (male:female=3.5:1)) were captured from two dedicated interventional cardiac machines (2 x GE Innova IGS 520) using GE DoseWatch (v3.1.0).
The data was exported to MS Excel (2016) for analysis.
For each of the three different PCI procedure types,
in ascending order of complexity,
i.e.
PCI (single vessel),
PCI MV (multivessel) and PCI CTO (Chronic Total Occlusion),
descriptive statistics were obtained for the captured dose metrics shown in Table 1.
Additionally,
Dose Reference Levels (Median (Q2) and 75th percentile (Q3)) for RPAK,
DAP,
and Peak Skin Dose (PSD) were calculated for each of the three types of PCI procedure and compared to published values.
Table 1 Parameters captured for each PCI Study: PCI,
PCI (MV) and PCI (CTO).
Patient sex |
Patient age |
Patient weight (kg) |
Patient height (cm) |
Patient BMI |
Image and Fluoroscopy Dose Area Product (DAP) (mGy.cm2) |
Total Time of Fluoroscopy (s) |
Total number of exposures |
Total Air Kerma (RPAK) (mGy) |
Number of Acquisition Series |
Total Acquisition Air Kerma (mGy) |
Total Acquisition DAP (mGy.cm²) |
Total Acquisition Time (s) |
Number of Fluoro Series |
Total Fluoro Air Kerma (mGy) |
Total Fluoro DAP (mGy.cm²) |
Peak Skin Dose (PSD) (mGy) |
|
Values of Reference Point Air Kerma (RPAK) and Dose Area Product (DAP) (aka Kerma Air Product) are automatically produced by the interventional radiology equipment and stored in the DICOM Radiation Dose Structured Report (RDSR).
These values are validated by local quality assurance programs to have an accuracy to within +/-10%.
PSD values are calculated by applying appropriate corrections to the RPAK values in the RDSR, which includes corrections for table height, attenuation in the table and mattress and backscatter for the beam size and energy.
These calculations are automatically carried out by the GE DoseWatch software using a standard methodology (4),(5), which produce PSD values within +/- 35% (6).