Chapter 7 Dose Check; Overview; Introduction - GE Revolution CT User Manual

Chapter 7 Dose Check

1 Overview

For dose measurements and calculations, refer to the Technical Reference Manual, Dose and
Performance chapter.

1.1 Introduction

Dose Check alerts you when the estimated dose index is above the limit set by the operating
group, practice, or institution. Dose Check complies with the NEMA XR-25 standard.
Dose Check creates awareness of the dose index of the prescribed scan, and launches a
notification if the dose index is above the limit. The notification is set at a level above routine or
normally expected doses, but not so high as to pose a significant risk to the patient. Depending
on patient size or imaging requirements, it may be appropriate to scan at a value above the
Notification Value (NV).
Notification Values are not necessarily the same as the published Diagnostic Reference Levels
(DRLs). However, these may be consulted as a guide to determine the appropriate NV for your
site and patient population. Because routine scanning does involve a range of applicable
techniques due to patient sizes and imaging needs, another consideration on where to set the
notification level will be the frequency in which your practice would want it posted.
Dose Check also issues an alert when the accumulated dose index would exceed the
institution's established range. GE has pre-populated the system-level Alert Value (AV) at 1000
mGy CTDI in accordance with the FDA November 8, 2010 letter to MITA.
vol
Dose Check should be incorporated into your department's Quality Assurance (QA) processes
to assure that scan protocols are defined with the "as low as reasonably achievable" (ALARA)
parameters, and to vary examination protocols to take into account patient body habitus. The
feature provides for audit capability and tracking when Notification and Alert Values are
exceeded and the capability to output the protocols on the system and the associated NVs
entered for them.
Dose Check provides the following:
•
Checks against a Notification Value and issues an alert if the estimated dose for the scan is
above your limit.
•
Checks against an Alert Value where the user needs specific authority to continue the scan
at the current estimated dose without changing the scan parameters.
•
Defines Alert Values for Adult and Pediatric imaging with an age threshold.
•
Audit logging and review.
• Protocol Change Control.
Chapter 7 Dose Check
NOTICE
Please refer to the Safety chapter for important safety information regarding the
use of the equipment and software on this system.
Attention: Consult accompanying documents.
Revolution CT User Manual
Direction 5480385-1EN, Revision 1
137