A Phantom Study and a Retrospective Clinical Analysis to Investigate the Impact of a New Image Processing Technology on Radiation Dose and Image Quality during Hepatic Embolization

doi:10.1016/j.jvir.2016.01.131

Journal of Vascular and Interventional Radiology

Volume 27, Issue 4, April 2016, Pages 593-600

https://doi.org/10.1016/j.jvir.2016.01.131 Get rights and content

Abstract

Purpose

To investigate changes in radiation dose and image quality using phantoms and hepatic embolization procedures performed with a new image processing technology (ClarityIQ) for a single-plane flat-detector–based interventional fluoroscopy system.

Materials and Methods

Phantom study was performed using acrylic sheets simulating different patient sizes. Air kerma rates (AKRs) were compared for different fluoroscopy modes and magnification modes without and with ClarityIQ. Repeat hepatic embolization procedures performed on the same lobe of the liver in the same patient by the same interventional radiologist between January 2013 and July 2014 without and with ClarityIQ were evaluated retrospectively. This included treatment of 33 hepatic lobes in 26 patients. Cumulative air kerma (CAK), kerma–area product (KAP), and factors affecting radiation dose were extracted from study metadata and compared. Blinded randomized image quality review was performed on arteriograms using a five-point scale.

Results

The phantom study revealed a significantly lower AKR (P < .005) with ClarityIQ. Repeated-measures analysis revealed a significant effect of ClarityIQ (P ≤ .001) on CAK and KAP, with reductions ranging between 9% and 85% (median, 67%) and between 5% and 89% (median, 75%), respectively, on a case-by-case basis. Mean reductions in CAK and KAP were 279 mGy and 134,030 mGy·cm², respectively. Image quality review scores were significantly lower (P ≤ .001) with ClarityIQ, effecting visualization of tumor vasculature and appearance of noise texture.

Conclusions

ClarityIQ resulted in radiation dose reduction in the phantom study and in the hepatic embolization procedures, but with a decrease in subjective perceptions of image quality.

Section snippets

Materials and Methods

All data were acquired from two single-plane flat-detector interventional fluoroscopy systems (Allura Xper FD20; Philips), labeled in the present paper as system 1 and system 2. System 2 was upgraded with ClarityIQ image processing technology in December 2013. System 1, installed in December 2009, and system 2, installed in April 2011, operated on similar software versions before the ClarityIQ upgrade of system 2 (version 8.1.3) during the course of the study period. Both systems had identical

Phantom Study

The maximum percentage error values between the system-reported AKR and measured AKR at the interventional reference point were 25.7% (ratio, 1.3; mean AKR error, 1.2 mGy/min; range, 0.0–6.7 mGy/min) for system 1 and 14.0% (ratio, 1.2; mean AKR error, 1.3 mGy/min; range, 0.0–5.1 mGy/min) and 19.0% (ratio, 1.2; mean AKR error, 0.4 mGy/min; range, 0.0–1.7 mGy/min) for system 2 before and after the upgrade with ClarityIQ technology, respectively. The discrepancy between measured and indicated CAK

Discussion

The present study demonstrates that ClarityIQ technology resulted in a reduction in radiation dose indicators based on controlled phantom experiments and a retrospective analysis of clinical procedures. Any reduction in radiation dose for such procedures will reduce the likelihood of tissue reactions and will decrease the occupational exposure to the staff (23), in addition to the reduction in occupational exposure achieved by following the standard as-low-as-reasonably-achievable principles.

References (29)

E. Vano et al.
Radiation-associated lens opacities in catheterization personnel: results of a survey and direct assessments
J Vasc Interv Radiol
(2013)
S. Balter et al.
Radiation dose measurements and monitoring for fluoroscopically guided interventional procedures
J Am Coll Radiol
(2012)
D.L. Miller et al.
Quality improvement guidelines for recording patient radiation dose in the medical record for fluoroscopically guided procedures
J Vasc Interv Radiol
(2012)
L.K. Wagner et al.
Management of patient skin dose in fluoroscopically guided interventional procedures
J Vasc Interv Radiol
(2000)
L.R. Dekker et al.
New image processing and noise reduction technology allows reduction of radiation exposure in complex electrophysiologic interventions while maintaining optimal image quality: a randomized clinical trial
Heart Rhythm
(2013)
NCRP Report 168: Radiation dose management for fluoroscopically guided interventional medical procedures
(2010)
S. Balter et al.
Fluoroscopically guided interventional procedures: a review of radiation effects on patients’ skin and hair
Radiology
(2010)
R. Ukisu et al.
Skin injuries caused by fluoroscopically guided interventional procedures: case-based review and self-assessment module
AJR Am J Roentgenol
(2009)
S. Balter et al.
Patient skin reactions from interventional fluoroscopy procedures
AJR Am J Roentgenol
(2014)
K.P. Kim et al.
Occupational radiation doses to operators performing fluoroscopically-guided procedures
Health Phys
(2012)

S. Jacob et al.

Eye lens radiation exposure to interventional cardiologists: a retrospective assessment of cumulative doses

Radiat Prot Dosimetry

(2013)

D.L. Miller et al.

Clinical radiation management for fluoroscopically guided interventional procedures

Radiology

(2010)

G. Bartal et al.

Management of patient and staff radiation dose in interventional radiology: current concepts

Cardiovasc Intervent Radiol

(2014)

Cited by (11)

Investigation of Radiation Dose Estimates and Image Quality Between Commercially Available Interventional Fluoroscopy Systems for Fluoroscopically Guided Interventional Procedures
2021, Academic Radiology
Citation Excerpt :
Some of these studies have looked at patient monitoring and follow-up after potentially-high radiation dose procedures (3,14), while some studies have looked at cumulative radiation dose utilization based on all interventional fluoroscopy systems at a particular site (2,13). There are other studies that have looked at the impact of vendor-specific product upgrades on radiation dose and image quality (15,18); however these studies are limited to comparisons of radiation dose and image quality for fluoroscopy systems from the same vendor (before and after upgrades). Another study comparing radiation dose utilization between fluoroscopy systems from different vendors was performed, but it was limited to investigations utilizing phantoms only (20).
To investigate differences in radiation dose and image quality for single-plane flat-panel-detector based interventional fluoroscopy systems from two vendors using phantom study and clinical procedures.
AlluraClarityIQ (Philips) and Artis Q (Siemens-Healthineers) interventional fluoroscopy systems were evaluated. Phantom study included comparison of system-reported air-kerma rates (AKR) for clinical protocols with simulated patient thicknesses (20–40 cm). Differences in system-reported radiation dose estimates, cumulative-air-kerma (CAK) and kerma-area-product (KAP), for different clinical procedures were investigated. Subset analysis investigated differences in CAK, KAP and other factors affecting radiation dose when the same patients underwent repeat embolization procedures performed by the same physician on the two different fluoroscopy systems. Two blinded interventional radiologists reviewed image-quality for these procedures using a five-point scale (1–5; 5-best) for five parameters.
Phantom study revealed that air-kerma rates was significantly higher for Artis Q system for 30–40cm of simulated patient thicknesses (p < 0.05). Overall data analysis from 4381 clinical cases revealed significant differences in CAK and KAP for certain procedures (p < 0.05); with significantly lower values for AlluraClarityIQ systems (median CAK lower by: 29%–58%). Subset analysis with 40 patients undergoing repeat embolization procedures on both systems revealed that median CAK and KAP were significantly lower for AlluraClarityIQ systems (p < 0.02) by 45% and 31%, respectively. Image quality scores for AlluraClarityIQ systems were significantly greater (mean difference range for five parameters: 1.3–1.6; p < 0.005).
Radiation dose and image quality differences were observed between AlluraClarityIQ and Artis Q systems. AlluraClarityIQ systems showed lower radiation utilization and an increase in subjective perception of image quality.
Evaluation of image quality and patient exposure in fluoroscopy using a phantom: Is there any clinical relevance?
2021, European Journal of Radiology
Citation Excerpt :
In a recent article [24], a clinical problem first observed in Pelvis digital radiographs of patients with metallic hip implant (the anatomy around the implant was misrepresented due to failure of the processing algorithm), was successfully investigated utilizing the same phantom. In the international literature there are many studies where phantoms were used for image quality evaluations and the results were correlated to specific clinical image quality evaluations [25–28]. Human cadavers have been also used for such image quality evaluation [29].
To investigate the impact of X-ray preset acquisition protocol settings on fluoroscopy image quality (IQ) and radiation exposure.
A quality control (QC) phantom was imaged with a modern digital C-arm system, using various preset fluoroscopy protocols. IQ was assessed using human observers and in-house software for automated evaluation, based on contrast-to-noise ratios of details and their background. Patient radiation exposure was evaluated using the displayed Incident Air-Kerma and Kerma-Area Product values.
Protocol selection affects radiation exposure by a factor of about 3. IQ evaluation showed that acquisition protocols produce images with quite different characteristics. The visual IQ evaluation method was time consuming and cumbersome. The automated method, utilized the visual IQ evaluation results for calibration of detection thresholds. However, it failed to reproduce these results for all images and details types. In some images, digital image processing created artifacts which affected the pixel value distributions around details in a way that could be handled only by the human vision.
Manufacturers provide many preset protocols designated for specific clinical uses, which have large impact on IQ characteristics and radiation exposure. However, protocol settings’ selection rationale is essentially a “black box” for the end user. Though QC phantoms are currently used for IQ evaluation, they are not appropriate for drawing firm conclusions concerning the expected performance of each protocol in clinical practice. Currently, there is no consensus on the optimum technical characteristics of preset protocols for specific procedures. More work is needed in this area.
The Medical Physicist's Role in Radiation Optimization
2017, Journal of the American College of Radiology
Tantalum-specific contrast-to-noise ratio or conventional detector dose-driven exposure control in angiography: radiation dose and image quality evaluation in a porcine model
2022, European Radiology Experimental
Performance evaluation of two interventional fluoroscope suites for cardiovascular imaging
2022, Journal of Applied Clinical Medical Physics
Application of Image Processing Technology in the Visual Design of Motion Health under the Background of Wireless Communication: Take Swimming as an Example
2022, Wireless Communications and Mobile Computing

View all citing articles on Scopus

: None of the authors have identified a conflict of interest.

View full text

Clinical StudyA Phantom Study and a Retrospective Clinical Analysis to Investigate the Impact of a New Image Processing Technology on Radiation Dose and Image Quality during Hepatic Embolization

Abstract

Purpose

Materials and Methods

Results

Conclusions

Section snippets

Materials and Methods

Phantom Study

Discussion

J Vasc Interv Radiol

J Am Coll Radiol

J Vasc Interv Radiol

J Vasc Interv Radiol

Heart Rhythm

NCRP Report 168: Radiation dose management for fluoroscopically guided interventional medical procedures

Fluoroscopically guided interventional procedures: a review of radiation effects on patients’ skin and hair

Radiology

Skin injuries caused by fluoroscopically guided interventional procedures: case-based review and self-assessment module

AJR Am J Roentgenol

Patient skin reactions from interventional fluoroscopy procedures

AJR Am J Roentgenol

Occupational radiation doses to operators performing fluoroscopically-guided procedures

Health Phys

Eye lens radiation exposure to interventional cardiologists: a retrospective assessment of cumulative doses

Radiat Prot Dosimetry

Clinical radiation management for fluoroscopically guided interventional procedures

Radiology

Management of patient and staff radiation dose in interventional radiology: current concepts

Cardiovasc Intervent Radiol

Clinical Study
A Phantom Study and a Retrospective Clinical Analysis to Investigate the Impact of a New Image Processing Technology on Radiation Dose and Image Quality during Hepatic Embolization