Abstract
Purpose
Non-contrast computed tomography (NCCT) is a first-line imaging technique for determining treatment options for acute ischemic stroke (AIS). However, its poor contrast and signal-to-noise ratio limit the diagnosis accuracy for radiologists, and automated AIS lesion segmentation using NCCT also remains a challenge. In this paper, we propose R2U-RNet, a novel model for AIS lesion segmentation using NCCT.
Methods
We used an in-house retrospective NCCT dataset with 261 AIS patients with manual lesion segmentation using follow-up diffusion-weighted images. R2U-RNet is based on an R2U-Net backbone with a novel residual refinement unit. Each input image contains two image channels from separate preprocessing procedures. The proposed model incorporates multiscale focal loss to mitigate the class imbalance problem and to leverage the importance of different levels of details. A proposed noisy-label training scheme is utilized to account for uncertainties in the manual annotations.
Results
The proposed model outperformed several iconic segmentation models in AIS lesion segmentation using NCCT, and our ablation study demonstrated the efficacy of the proposed model. Statistical analysis of segmentation performance revealed significant effects of regional stroke occurrence and side of the stroke, suggesting the importance of region-specific information for automated segmentation, and the potential influence of the hemispheric difference in clinical data.
Conclusion
This study demonstrated the potentials of R2U-RNet model for automated NCCT AIS lesion segmentation. The proposed model can serve as a tool for accelerating AIS diagnoses and improving the treatment quality of AIS patients.





Similar content being viewed by others
References
Barber PA, Demchuk AM, Zhang J, Buchan AM, Lancet ASGJT (2000) Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. Lancet 355(9216):1670–1674. https://doi.org/10.1016/S0140-6736(00)02237-6
Von Kummer R, Bourquain H, Bastianello S, Bozzao L, Manelfe C, Meier D, Hacke W (2001) Early prediction of irreversible brain damage after ischemic stroke at CT. Radiology 219(1):95–100
Vilela P, Rowley HAJE (2017) Brain ischemia: CT and MRI techniques in acute ischemic stroke. 96:162-172
Lövblad K-O, Altrichter S, Pereira VM, Vargas M, Gonzalez AM, Haller S, Sztajzel RJJON (2015) Imaging of acute stroke: CT and/or MRI. 42 (1):55–64
Na DG, Kim EY, Ryoo JW, Lee KH, Roh HG, Kim SS, Song IC, Chang K-H (2005) CT sign of brain swelling without concomitant parenchymal hypoattenuation: comparison with diffusion-and perfusion-weighted MR imaging. Radiology 235(3):992–998
Allen LM, Hasso AN, Handwerker J, Farid H (2012) Sequence-specific MR imaging findings that are useful in dating ischemic stroke. Radiographics 32(5):1285–1297
Furie KL, Jayaraman MV (2018) 2018 Guidelines for the early management of patients with acute ischemic stroke. Stroke 49(3):509–510. https://doi.org/10.1161/STROKEAHA.118.020176
Barber PA, Demchuk AM, Zhang J, Buchan AM, Group AS (2000) Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. Lancet 355(9216):1670-1674
Kuang H, Najm M, Chakraborty D, Maraj N, Sohn S, Goyal M, Hill M, Demchuk A, Menon B, Qiu W (2019) Automated ASPECTS on noncontrast CT scans in patients with acute ischemic stroke using machine learning. Am J Neuroradiol 40(1):33–38
Ronneberger O, Fischer P, Brox T (2015) U-net: convolutional networks for biomedical image segmentation. International conference on medical image computing and computer-assisted intervention. Springer, New York, pp 234–241
Alom MZ, Hasan M, Yakopcic C, Taha T, Asari V (2018) Recurrent residual convolutional neural network based on U-Net (R2U-Net) for medical image segmentation
Jin Q, Meng Z, Sun C, Cui H, Su R (2020) RA-UNet: A hybrid deep attention-aware network to extract liver and tumor in CT scans. Front Bioeng Biotechnol 8:1471
Chen L, Bentley P, Rueckert DJNC (2017) Fully automatic acute ischemic lesion segmentation in DWI using convolutional neural networks. Neuroimage Clin 15:633–643. https://doi.org/10.1016/j.nicl.2017.06.016
Perez Malla CU, Valdes Hernandez MdC, Rachmadi MF, Komura T (2019) Evaluation of enhanced learning techniques for segmenting ischaemic stroke lesions in brain magnetic resonance perfusion images using a convolutional neural network scheme. Front Neuroinform 13:33
Tomita N, Jiang S, Maeder ME, Hassanpour S (2020) Automatic post-stroke lesion segmentation on MR images using 3D residual convolutional neural network. NeuroImage Clin 27:102276. https://doi.org/10.1016/j.nicl.2020.102276
Wang G, Song T, Dong Q, Cui M, Huang N, Zhang S (2020) Automatic ischemic stroke lesion segmentation from computed tomography perfusion images by image synthesis and attention-based deep neural networks. Med Image Anal 65:101787
Song T, Huang N (2018) Integrated extractor, generator and segmentor for ischemic stroke lesion segmentation. International MICCAI Brainlesion Workshop. Springer, New York, pp 310–318
Abulnaga SM, Rubin J (2018) Ischemic stroke lesion segmentation in CT perfusion scans using pyramid pooling and focal loss. International MICCAI Brainlesion Workshop. Springer, New York, pp 352–363
Clèrigues A, Valverde S, Bernal J, Freixenet J, Oliver A, Lladó X (2019) Acute ischemic stroke lesion core segmentation in CT perfusion images using fully convolutional neural networks. Comput Biol Med 115:103487
Dolz J, Ayed IB, Desrosiers C (2018) Dense multi-path U-Net for ischemic stroke lesion segmentation in multiple image modalities. International MICCAI Brainlesion Workshop. Springer, New York, pp 271–282
Xue Y, Farhat FG, Boukrina O, Barrett AM, Binder JR, Roshan UW, Graves WW (2020) A multi-path 2.5 dimensional convolutional neural network system for segmenting stroke lesions in brain MRI images. NeuroImage Clin 25:102118. https://doi.org/10.1016/j.nicl.2019.102118
Zhang J, Lv X, Sun Q, Zhang Q, Wei X, Liu B (2020) SDResU-net: separable and dilated residual U-net for MRI brain tumor segmentation. Curr Med Imag 16(6):720–728
Aygün M, Şahin YH, Ünal G (2018) Multi modal convolutional neural networks for brain tumor segmentation
Fuchigami T, Akahori S, Okatani T, Li Y (2020) A hyperacute stroke segmentation method using 3D U-Net integrated with physicians’ knowledge for NCCT. In: Medical Imaging 2020: Computer-Aided Diagnosis, 2020. International Society for Optics and Photonics, p 113140G
Kuang H, Menon BK, Sohn SI, Qiu W (2021) EIS-Net: segmenting early infarct and scoring ASPECTS simultaneously on non-contrast CT of patients with acute ischemic stroke. Med Image Anal 70:101984
Qiu W, Kuang H, Teleg E, Ospel JM, Sohn SI, Almekhlafi M, Goyal M, Hill MD, Demchuk AM, Menon BK (2020) Machine learning for detecting early infarction in acute stroke with non–contrast-enhanced CT. Radiology 294(3):638–644
Kuang H, Menon BK, Qiu W (2020) Automated stroke lesion segmentation in non-contrast CT scans using dense multi-path contextual generative adversarial network. Phys Med Biol 65(21):215013
Kuang H, Menon BK, Qiu W (2019) Semi-automated infarct segmentation from follow-up noncontrast CT scans in patients with acute ischemic stroke. Med Phys 46(9):4037–4045
Tuladhar A, Schimert S, Rajashekar D, Kniep HC, Fiehler J, Forkert ND (2020) Automatic segmentation of stroke lesions in non-contrast computed tomography datasets with convolutional neural networks. IEEE Access 8:94871–94879
Mirikharaji Z, Yan Y, Hamarneh G (2019) Learning to segment skin lesions from noisy annotations. In: Wang Q, Milletari F, Nguyen HV et al (eds) Domain adaptation and representation transfer and medical image learning with less labels and imperfect data, 2019. Springer, Cham, pp 207–215
Sukhbaatar S, Bruna J, Paluri M, Bourdev L, Fergus R (2014) Training convolutional networks with noisy labels
Tajbakhsh N, Jeyaseelan L, Li Q, Chiang JN, Wu Z, Ding X (2020) Embracing imperfect datasets: a review of deep learning solutions for medical image segmentation. Med Image Anal 63:101693. https://doi.org/10.1016/j.media.2020.101693
Hazimeh H, Ponomareva N, Mol P, Tan Z, Mazumder R (2020) The tree ensemble layer: differentiability meets conditional computation
Pizer SM, Amburn EP, Austin JD, Cromartie R, Geselowitz A, Greer T, ter Haar RB, Zimmerman JB, Zuiderveld K (1987) Adaptive histogram equalization and its variations. Comput Vis Graph Image Process 39(3):355–368
Lai W-S, Huang J-B, Ahuja N, Yang M-H (2018) Fast and accurate image super-resolution with deep laplacian pyramid networks. IEEE Trans Pattern Anal Mach Intell 41(11):2599–2613
Lin T-Y, Goyal P, Girshick R, He K, Dollár P (2017) Focal loss for dense object detection. In: Proceedings of the IEEE international conference on computer vision. pp 2980–2988
Clèrigues A, Valverde S, Bernal J, Freixenet J, Oliver A, Lladó X (2020) Acute and sub-acute stroke lesion segmentation from multimodal MRI. Comput Methods Prog Biomed 194:105521
Zhou Y, Huang W, Dong P, Xia Y, Wang S (2019) D-UNet: a dimension-fusion U shape network for chronic stroke lesion segmentation. IEEE/ACM Trans Comput Biol Bioinform
Liu L, Kurgan L, Wu F-X, Wang J (2020) Attention convolutional neural network for accurate segmentation and quantification of lesions in ischemic stroke disease. Med Image Anal 65:101791
Jaccard P (1901) Distribution de la flore alpine dans le bassin des Dranses et dans quelques régions voisines. Bull Soc Vaudoise Sci Nat 37:241–272
Dice LR (1945) Measures of the amount of ecologic association between species. Ecology 26(3):297–302
Yeghiazaryan V, Voiculescu ID (2018) Family of boundary overlap metrics for the evaluation of medical image segmentation. J Med Imag 5(1):015006
Ashburner J, Barnes G, Chen C, Daunizeau J, Flandin G, Friston K, Kiebel S, Kilner J, Litvak V, Moran RJWTCfN, London, UK (2014) SPM12 manual.2464
Macciocchi SN, Diamond PT, Alves WM, Mertz T (1998) Ischemic stroke: relation of age, lesion location, and initial neurologic deficit to functional outcome. Arch Phys Med Rehabil 79(10):1255–1257. https://doi.org/10.1016/S0003-9993(98)90271-4
Foerch C, Misselwitz B, Sitzer M, Berger K, Steinmetz H, Neumann-Haefelin T (2005) Difference in recognition of right and left hemispheric stroke. Lancet 366(9483):392–393. https://doi.org/10.1016/S0140-6736(05)67024-9
Portegies ML, Selwaness M, Hofman A, Koudstaal PJ, Vernooij MW, Ikram MA (2015) Left-sided strokes are more often recognized than right-sided strokes: the Rotterdam study. Stroke 46(1):252–254
Group ES (1996) Silent brain infarction in nonrheumatic atrial fibrillation: European Atrial Fibrillation Trial. Neurology 46:159-165
Funding
This work was supported in part by the Kaohsiung Chang Gung Memorial Hospital (CMRPG8H0951 and CMRPG8K0131), the Higher Education Sprout Project of National Yang Ming Chiao Tung University and Ministry of Education (MOE), and Ministry of Science and Technology (MOST 110-2634-F-A49-005), Taiwan.
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Conflict of interest
The authors have no conflict of interest to disclose.
Ethical approval
This study was carried out in accordance with the recommendations of the Institutional Review Board of our hospital. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The protocol was approved by the research ethics committee of Kaohsiung Chang Gung Memorial Hospital (IRB#: 201800955B0, 201800955B0C101, and 201800955B0C102).
Informed consent
Informed consent was obtained from all individual participants included in the study.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Lin, SY., Chiang, PL., Chen, PW. et al. Toward automated segmentation for acute ischemic stroke using non-contrast computed tomography. Int J CARS 17, 661–671 (2022). https://doi.org/10.1007/s11548-022-02570-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11548-022-02570-x