A visual grading analysis-based audit for MR simulation sequence development
McDaid, Lisa Cooper, L. Edwards, T. McPartlin, Andrew J Bonington, Suzanne C Eccles, Cynthia L
McDaid, Lisa
Cooper, L.
Edwards, T.
McPartlin, Andrew J
Bonington, Suzanne C
Eccles, Cynthia L
Citations
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Abstract
Purpose or Objective
To assess recently implemented MR Simulation protocols
used for treatment planning in head and neck patients
being treated as part of a newly introduced proton beam
radiotherapy (PBT) service.
Material and Methods
Based on a review of the literature, an imaging protocol
comprising four sequences was implemented. Imaging was
performed using a 1.5 Tesla (T) magnet, utilising a
combination of 32-channel body array, 44-channel spinal
array and two large flexible 2-channel transmit receive
coils. Table 1 details the sequences used, but in short
included 2- and 3 – dimensional acquisitions using turbo
spin echo (TSE), driven equilibrium (DRIVE), spectral presaturation
with inversion (SPIR) and mDixon
sequences. All patients were imaged axially from superior
orbital margin to sternal notch in the treatment
position. To evaluate image quality and suitability, an
audit was undertaken, using a visual grading analysis
(VGA). The VGA was based on a 4-point scale, ranging
from “very clear” to “not visible” for a series of predetermined
structures (table 2) by 3 multidisciplinary
team members.
Results
Sixteen patient datasets were available for review. The
preliminary analysis demonstrated a scan time of 31.26
minutes, with a mean ‘in-room’ time of 64.07 minutes
(range 24-101 minutes). Using VGA tool, one
radiographer, one radiologist and one clinical oncologist
reviewed images (Table 1). Overall, an average of 69.4%
of the sequences and structures were reported as “very
clear” or “clear” (range 57.1-87.3%) (Table 2). The T2W
TSE mDixon and T1 SPIR with intravenous contrast were
the 2 sequences that scored the highest. The 3D T2W
DRIVE sequence came out as unclear or had structures that
weren’t visible in nearly 43% of the cases.
Conclusion
Based on our analysis, the most appropriate sequences for
planning PBT for head and neck tumours are a combination
of T2W TSE mDixon and T1 SPIR with intravenous
contrast. Considering clarity of named anatomical
structures has facilitated an optimisation process of
individual sequences.
Using interdisciplinary VGA as an audit tool, we have
implemented a continuous quality improvement (CQI)
process for PBT treatment planning in head and neck
cancers using MR. We anticipate this process will soon be
implemented for other treatment sites at our institution.
This philosophy of CQI will ensure sequence selection is
evidence-based, the inclusion of appropriately selected
sequences, and the removal of sequences felt to be less
useful.
Description
Date
2020
Publisher
Collections
Keywords
Type
Meetings and Proceedings
Citation
McDaid L, Cooper L, Edwards T, McPartlin A, Bonington S, Eccles C. PO-1876: A visual grading analysis-based audit for MR simulation sequence development. Radiotherapy and Oncology . 2020 Nov;152:S1045–6.