Aims and objectives
In patients with acute ischemic stroke,
intra-arterial thrombolytic therapy has proven to decrease morbidity and mortality (1).
this increases the risk of intracerebral haemorrhage (ICH) (2-5).
Because of the breakdown of the blood-brain barrier,
contrast extravasation can occur during the procedure,
complicating the detection of ICH due to the overlap in density.
As of writing,
unenhanced conventional CT is performed within 24 hours after treatment for the detection of complications...
Methods and materials
Image acquisition: All scans were performed with a Gammex 464 phantom (Gammex,
Madison WI) with a plastic 50-ml tube in its air cavity,
filled with a sample simulating haemorrhage (blood),
diluted iodine and a haemorrhage-iodine (blood-iodine) mixture consecutively. Each sample was scanned in the phantom with the following scan settings on the clinical IQon SDCT scanner: 200 mAs,
gantry rotation time 330 ms and detector collimation 64 x 0.625 mm.
Images were reconstructed...
There was a significant correlation between attenuation measurements on the conventional and VNC images,
for all samples containing blood (R 2 > 0.97,
For the samples containing blood,
correlation was highest for pure blood dilutions (R 2 = 1.00) and lowest for samples containing 33% blood (R 2 = 0.97).
Correlation was not significant for samples with pure iodine (R 2 = 0.77,
p = 0.08). Relative retention of VNC attenuation was significantly different between all categories...
The purpose of our study was to investigate the ability of SDCT to differentiate intra-cranial haemorrhage from iodinated contrast in a phantom model.
Measuring the retention of attenuation in a ROI,
by comparing attenuation on VNC to conventional images,
showed excellent accuracy for detecting haemorrhage.
we propose a method of classification,
allowing accurate estimation of the haemorrhagic component size. A >20% cut-off value for VNC attenuation retention,
Steven Van Hedent,
MD University Hospital Brussels,
Free University Brussels,
Department of Radiology,
Brussels - Belgium. Laarbeeklaan 101 1090 Brussels,
Belgium Phone: +3224775373 e-mail: email@example.com
1. The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group (1995) Tissue plasminogen activator for acute ischemic stroke.
N Engl J Med 333:1581–1587 2. Mokin M,
Kass-Hout T et al (2012) Intracerebral hemorrhage secondary to intravenous and endovascular intraarterial revasculari- zation therapies in acute ischemic stroke: an update on risk factors,
Neurosurg Focus 32:E2 3. 4.
von Kummer R et al (1999)...