Toward fully automated processing of dynamic susceptibility contrast perfusion MRI for acute ischemic cerebral stroke

• Published in: Computer methods and programs in biomedicine Vol. 98; no. 2; pp. 204 - 213
• Main Authors: Kim, Jinsuh, Leira, Enrique C., Callison, Richard C., Ludwig, Bryan, Moritani, Toshio, Magnotta, Vincent A., Madsen, Mark T.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ireland Ltd 01.05.2010; Elsevier
• Subjects: Algorithms; Automatic Data Processing; Biological and medical sciences; Brain - blood supply; Brain Ischemia - diagnosis; Cerebrovascular Circulation; Contrast Media; Deconvolution; Dynamic susceptibility contrast; Humans; Image Interpretation, Computer-Assisted; Internal Medicine; Ischemic stroke; Magnetic Resonance Angiography - statistics & numerical data; Medical sciences; Motion correction; MRI; Other; Perfusion; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Software; Stroke - diagnosis; Technology. Biomaterials. Equipments. Material. Instrumentation; SVD; ITK; PACS; MRI; iPAT; Ischemic stroke; MTT; TTP; rCBV; DSC; DWI; Dynamic susceptibility contrast; DICOM; AIF; rCBF; PWI; SSE; SSD; Motion correction; TE; Deconvolution; Perfusion; BAT; FWHM; Software; TR; digital imaging and communications in medicine image; picture archiving and communications system; echo time; perfusion-weighted imaging; singular value decomposition; time-to-peak; repetition time; integrated parallel acquisition technique; insight toolkit; regional cerebral blood volume; sum of squared difference; diffusion-weighted imaging; sum of squared error; mean transit time; full width at half maximum; regional cerebral blood flow; bolus arrival time; arterial input function; Nuclear magnetic resonance imaging; Biomedical engineering
• ISSN: 0169-2607; 1872-7565; 1872-7565
• DOI: 10.1016/j.cmpb.2009.12.005

We developed fully automated software for dynamic susceptibility contrast (DSC) MR perfusion-weighted imaging (PWI) to efficiently and reliably derive critical hemodynamic information for acute stroke treatment decisions. Brain MR PWI was performed in 80 consecutive patients with acute nonlacunar ischemic stroke within 24 h after onset of symptom from January 2008 to August 2009. These studies were automatically processed to generate hemodynamic parameters that included cerebral blood flow and cerebral blood volume, and the mean transit time (MTT). To develop reliable software for PWI analysis, we used computationally robust algorithms including the piecewise continuous regression method to determine bolus arrival time (BAT), log-linear curve fitting, arrival time independent deconvolution method and sophisticated motion correction methods. An optimal arterial input function (AIF) search algorithm using a new artery-likelihood metric was also developed. Anatomical locations of the automatically determined AIF were reviewed and validated. The automatically computed BAT values were statistically compared with estimated BAT by a single observer. In addition, gamma-variate curve-fitting errors of AIF and inter-subject variability of AIFs were analyzed. Lastly, two observes independently assessed the quality and area of hypoperfusion mismatched with restricted diffusion area from motion corrected MTT maps and compared that with time-to-peak (TTP) maps using the standard approach. The AIF was identified within an arterial branch and enhanced areas of perfusion deficit were visualized in all evaluated cases. Total processing time was 10.9 ± 2.5 s (mean ± s.d.) without motion correction and 267 ± 80 s (mean ± s.d.) with motion correction on a standard personal computer. The MTT map produced with our software adequately estimated brain areas with perfusion deficit and was significantly less affected by random noise of the PWI when compared with the TTP map. Results of image quality assessment by two observers revealed that the MTT maps exhibited superior quality over the TTP maps (88% good rating of MTT as compared to 68% of TTP). Our software allowed fully automated deconvolution analysis of DSC PWI using proven efficient algorithms that can be applied to acute stroke treatment decisions. Our streamlined method also offers promise for further development of automated quantitative analysis of the ischemic penumbra.