3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke.
BACKGROUND
Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition.


METHODS
Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better).


RESULTS
Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2).


CONCLUSIONS
The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement.
Department of Biomedical Engineering and Physics, Academic Medical Center, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands, f.fahmi@amc.uva.nl.
Fahmi
F
Fahmi
Henk A
HA
Marquering
Jordi
J
Borst
Geert J
GJ
Streekstra
Ludo F M
LF
Beenen
Joris M
JM
Niesten
Birgitta K
BK
Velthuis
Charles B L
CB
Majoie
Ed
E
vanBavel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000000981:diagnostic imaging*; D005260:Female; D019416:Head Movements; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D020521:Stroke / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*