Aims and objectives
A non-contrast head CT scan is the standard radiologic test for patients presenting with stroke-like symptoms [1] in the emergency department,
due to its speed of imaging,
widespread availability and low cost.
The default window level in a cranial CT scan is around 40 Hounsfield units (HU),
with a window width of about 80 HU ("brain windows"); in our instution,
a window level of 40 HU and width of100 HU is used.Increase in lesion conspicuity and improved accuracy of non-enhanced CT stroke detectionmay be achieved...
Methods and materials
A retrospective cross-sectional design was utilized using the review of record database of the Department of Radiology,
De La Salle University Medical Center in Dasmarinas,
Cavite,
Philippines,
from the period of January 2015 to December 2017.
Sixty patients aged 30 to 80 years old,
who were diagnosed with a hyperacute infarction on initial CT scan examination and had subsequent follow-up CT or MRI study confirming infarction,
were included in the study.The head CT scan images of these patients were reviewed using"brain windows"settings (window level of...
Results
Accuracy rate is the percentage of correct detection over total number of patients.
"Stroke windows" was able to detect 92% correctly,
with "brain windows" only detecting 68%.Fig. 9
Sensitivity for "stroke windows" is 86.67% (75.41% to 94.06%),
while for "brain windows" is 46.67% (33.67% to 60.00%)- stroke detection is more sensitive using "stroke windows" than "brain windows".
Specificity for both "stroke windows" and "brain windows" is 100% (91.19% to 100.00%) - both are equal in identifying the absence of hyperacute infarction.
Positive predictive value for...
Conclusion
Non-contrast head CT scan remains the best imaging modality for detecting hyperacute infarction in the emergency setting [4].
"Stroke windows" is more accurate in detecting hyperacute infarction than "brain windows" when using non-contrast CT scan(92% versus 68%).
This is similar but not as striking as theresult foundby Mainali,
et al.
showing an increase in stroke detection with 70% using "stroke windows",
versus 18% using"brain windows" [1].
"Stroke windows" should be included in the standard imaging of emergency CT scans requested for patients with stroke-like symptoms,...
Personal information
Katrina Anne R.
Balalta,
MD
Address: Department of Radiology,
DLSU Medical Center,
Dasmarinas,
Cavite 4114
Contact #: +63 917 8375926 / +6346 4818000 local 1213
E-mail address:
[email protected]
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