Occupational and patient exposure in coronary angiography procedures

Assessment of patient and occupational exposure and radiation risk from cath-lab procedure

Due to the extended localized fluoroscopy, many radiographic exposures, and multiple procedures that might result in tissue reaction, patients and personnel received a significant radiation dose during interventional cardiology (IR) procedures. This study aims to calculate the radiation risk and assess patient and staff effective doses during IC procedures. Thirty-two patients underwent a Cath lab treatment in total. Ten Cath lab personnel, including six nurses, two cardiologists, and two X-ray technologists. Optical stimulating-luminescent dosimeters (OSL) (Al2O3:C) calibrated for this purpose were used to monitor both occupational and ambient doses. Using an automated OSL reader, these badges were scanned. The Air Kerma (mGy) and Kerma Area Products (KAP, mGy.cm2) have a mean and standard deviation (SD) of 371 ± 132 and 26052, respectively. The average personal dose equivalent (mSv) and its range for cardiologists, nurses and X ray technologists were 1.11 ± 0.21 (0.96-1.26), 0.84 ± 0.11 (0.68-1.16), and 0.68 ± 0.014 (0.12-0.13), respectively. The current study findings showed that the annual effective dose for cardiologists, nurses, and X-ray technologists was lesser than the yearly occupational dose limit of 20 mSv recommended by national and international guidelines. The patients' doses are comparable with some previously published studies and below the tissue reaction limits.

Evaluation of patient and staff exposure with state of the art X-ray technology in cardiac catheterization: A randomized controlled trial

INTRODUCTION

Cardiac catheterization procedures result in high patient radiation exposure and corresponding staff doses are reported to be among the highest for medical staff. The purpose of current randomized controlled study was to quantify the potential radiation dose reduction for both patient and staff, enabled by recent X-ray technology. This technology is equipped with advanced image processing algorithms, real-time dose monitoring, and an acquisition chain optimized for cardiac catheterization applications.

METHODS

A total of 122 adult patients were randomly assigned to one of two cath labs, either the reference X-ray modality (Allura Xper FD10, Philips Healthcare, the Netherlands) or the new X-ray system (AlluraClarity FD20/10 Philips Healthcare, the Netherlands). Exposure parameters and staff dosimeter readings were recorded for each exposure. Technical measurements were performed to define the radiation scatter behavior.

RESULTS

With the newer equipment, patient radiation dose is reduced (as total dose-area product) by 67% based on geometric means with 95%CI of 53%, 77% for diagnostic and interventional procedures. The C-arm and leg dosimeter readings were both reduced with 65% (P < 0.001), while for the collar and chest dosimeter readings no statistically significant reduction was noticed.

CONCLUSION

The new x-ray and image processing technology, significantly reduces patient dose in coronary angiographies, and PCIs by 67%. In general, scatter dose was also reduced, yet for some dosimeters the reduction was limited and not statistically significant. This study clearly indicates that the scatter behavior is highly dependent on C-arm rotation, operator movement and height, dosimeter position, beam filtration, clinical procedure type and system geometry.

Patient Exposure during Fluoroscopy-guided Pacemaker Implantation Procedures

A pacemaker, which is used for heart resynchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of pacemaker implantation procedures has increased to more than 50% worldwide. During this procedure, patients can be exposed to excessive radiation exposure. Wide range of doses has been reported in previous studies, suggesting that optimization of this procedure has not been fulfilled yet. The current study evaluated patient radiation exposure during cardiac pacemaker procedures and quantified the patient effective dose. A total of 145 procedures were performed for five pacemaker procedures (VVI, VVIR, VVD, VVDR, and DDDR) at two hospitals. Patient doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from the National Radiological Protection Board (NRPB, now The Health Protection Agency). The effective dose values were used to estimate cancer risk from the pacemaker procedure. Patient demographic data and exposure parameters for fluoroscopy and radiography were quantified. The mean patient doses ± SD per procedure (Gycm²) for VVI, VVIR, VVD, VVDR, and DDDR were 1.52 ± 0.13 (1.43-1.61), 3.28 ± 2.34 (0.29-8.73), 3.04 ± 1.67 (1.57-4.86), 6.04 ± 2.326 3.29-8.58), and 8.8 ± 3.6 (4.5-26.20), respectively. The overall patient effective dose was 1.1mSv per procedure. It is obvious that the DDDR procedure exposed patients to the highest radiation dose. Patient dose variation can be attributed to procedure type, exposure parameter settings, and fluoroscopy time. The results of this study showed that patient doses during different pacemaker procedures are lower compared to previous reported values. Patient risk from pacemaker procedure is low, compared to other cardiac interventional procedures. Patients' exposures were mainly influenced by the type of procedures and the clinical indication.