Fig 3 - uploaded by Israna Hossain Arka
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3D illustration of the FOV for the dynamic CT (red) and CTA (blue) scans. An example slice for each scan is also shown.

3D illustration of the FOV for the dynamic CT (red) and CTA (blue) scans. An example slice for each scan is also shown.

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Conference Paper
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In this paper we present a pre-processing stage for an automated volumetric CT stroke image diagnosis system. It concerns the automatic intensity-based 3D image registration of dynamic CT (used for CT perfusion imaging) to CT angiography (CTA) images. The dynamic CT images were acquired with a gantry tilt and hence the correct geometry is found. Th...

Context in source publication

Context 1
... implicitly and a tilt corrected image is only constructed after it has been registered to the CTA image. Basically the tilt correction is performed as applying a transformation T tc , which can be derived from the gantry tilt information in the DICOM files, as shown in Table I. The result of applying this transformation is illustrated in Fig. 3, where the blue box indicates the FOV of the CTA image, whereas the red box indicates the FOV of the CTP image which has tilted slices. An example slice of each image is also ...

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Citations

... Finally, Ref. [9] introduced an image processing system which included a phase of registration of brain MR images captured in different time points for the identification of the areas affected by the stroke. In the context of the CT angiogram, Ref. [10] proposed a preprocessing step for CT stroke diagnosis based on 3D image registration of dynamic CT exams and CT angiograms. Also, Ref. [11] introduced an image registration method for registering multi modal (CT or MR) brain exams and carotid arteries from ascending aorta to brain angiograms with multiple focus. ...
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We present a new system based on tracking the temporal evolution of stroke lesions using an image registration technique on CT exams of the patient's brain. The system is able to compare past CT exams with the most recent one related to stroke event in order to evaluate past lesions which are not related to stroke. Then, it can compare recent CT exams related to the current stroke for assessing the evolution of the lesion over time. A new similarity measure is also introduced for the comparison of the source and target images during image registration. It will result in a cheaper, faster and more accessible evaluation of the acute phase of the stroke overcoming the current limitations of the proposed systems in the state-of-the-art.
... Finally, Ref. [9] introduced an image processing system which included a phase of registration of brain MR images captured in different time points for the identification of the areas affected by the stroke. In the context of the CT angiogram, Ref. [10] proposed a preprocessing step for CT stroke diagnosis based on 3D image registration of dynamic CT exams and CT angiograms. Also, Ref. [11] introduced an image registration method for registering multi modal (CT or MR) brain exams and carotid arteries from ascending aorta to brain angiograms with multiple focus. ...
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