Aims and objectives
Diffusion-weighted imaging (DWI) is useful for detecting bladder
tumors.
In DWI,
increasing b values suppresses signals from urine in the
bladder.
However,
b values at which signals from the urine are suppressed
differ among individuals.
At our hospital,
images are taken at b values of
50,
800,
and 1000 s/mm2 for bladder tumors.
In some cases,
it is difficult
to identify tumors within the bladder due to signals from the urine.
In such
cases,
additional images are usually taken at b values of 1500 s/mm2...
Methods and materials
A double-blind study was conducted using 40 randomly selected MRI
(magnetic resonance imaging) images taken for suspected pelvic tumors at
our hospital between 2013 and 2017.
Of these,
three images with many
motion artifacts were excluded.
This study was conducted upon obtaining
approval from the ethics committee at our hospital.
To demonstrate whether cDWI is effectivewhen taken by any machines
and under any conditions,
images obtained from different machines were
randomly selected,
and cDWI images were developed
using the Osirix software.
Then,
significance of CNRs...
Results
The results from 37 compared images showed no significant differences in
cDWI images and actual DWI images taken at a bvalue of 1500
s/mm2 .
However,
at a b value of 2000 s/mm2 ,
cDWI showed
a clear tendency for increased CNRs,
and the t-test revealed significant
differences (P<0.01).(Fig.
4) The mean cDWI image score determined by our
radiologist was 71.4.
There were some cDWI images that scored higher
than the DWI images.(Fig.
2.3)
Conclusion
cDWI images generally have a poor signal-to-noise ratio (SNR),
and much
noise appears on the images.
Therefore,
some experts say cDWI images are
not suitable for interpretation.
However,
the present study clearly showed
that CNRs significantly increased in cDWI.
This was attributed to using a
cDWI software by MedTools,
which was plugged into the Osirix
software.
This cDWI software has a function to eliminate low apparent
diffusion coefficients (ADC),
which are noise-making factors in cDWI,
and
also a window level and window width (WL/WW) auto-setting...
Personal information
[email protected]
TOKYO city cyuuouku nihonnbashi 3-1-17 nihonnbashi horose building 2F
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