Abstract
The hyperdense middle cerebral artery (MCA) dot sign representing a thromboembolus is one of the important computed tomography (CT) findings for acute stroke on unenhanced CT images. Our purpose in this study was to develop an automated method for detection of the MCA dot sign of acute stroke on unenhanced CT images. The algorithm of the method which we developed consisted of 5 major steps: extraction of the sylvian fissure region, initial identification of MCA dots based on the morphologic top-hat transformation, feature extraction of candidates, elimination of false positives (FPs) by use of a rule-based scheme, and classification of candidates using a support vector machine (SVM) classifier with four features. Our database comprised 297 CT images obtained from seven patients with the MCA dot sign. The performance of this scheme for classification of the MCA dot sign was evaluated by means of a leave-one-case out method. The performance of the classification by use of the SVM achieved a maximum sensitivity of 97.5 % (39/40) at a FP rate of 1.28 per image. The sensitivity for detection of the MCA dot sign was 97.5 % (39/40) with a FP rate of 0.5 per hemisphere. The method we developed has the potential to detect the MCA dot sign of acute stroke on unenhanced CT images.
Similar content being viewed by others
References
Adams H, Adams R, del Zoppo G. Guidelines for the early management of patients with ischemic stroke: 2005 guidelines update a scientific statement from the Stroke Council of the American Heart Association/American Stroke Association. Stroke. 2005;36:916–23.
Adams HP Jr, Adams RJ, Brott T, del Zoppo GJ, Furlan A, Goldstein LB, Grubb RL, Higashida R, Kidwell C, Kwiatkowski TG, Marler JR, Hademenos GJ. Guidelines for the early management of patients with ischemic stroke: a scientific statement from the Stroke Council of the American Stroke Association. Stroke. 2003;34:1056–83.
Balbel PA, Demchuk AM, Zhang J, Buchan AM. Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. Lancet. 2000;355:1670–4.
Provenzale JM, Jahan R, Naidich TP, Fox AJ. Assessment of the patient with hyperacute stroke: imaging and therapy. Radiology. 2003;229:347–59.
Schriger DL, Karafut M, Starkman S, Krueger M, Saver JL. Cranial computed tomography interpretation in acute stroke: physician accuracy in determining eligibility for thrombolytic therapy. JAMA. 1998;279:1293–7.
Wardlaw JM, Mielke O. Early signs of brain infarction at CT: observer reliability and outcome after thrombolytic treatment—systematic review. Radiology. 2005;235:444–53.
Leys D, Pruvo JP, Godefroy O, Rondepierre P, Leclerc X. Prevalence and significance of hyperdense middle cerebral artery in acute stroke. Stroke. 1992;23:317–24.
Manelfe C, Larrue V, von Kummer R, Bozzao L, Ringleb P, Bastianello S. Association of hyperdense middle cerebral artery sign with clinical outcome in patients treated with tissue plasminogen activator. Stroke. 1999;30:769–72.
Kirchhof K, Welzel T, Mecke C, Zoubaa S, Sartor K. Differentiation of white, mixed, and red thrombi: value of CT in estimation of the prognosis of thrombolysis—phantom study. Radiology. 2003;228:126–30.
Barber PA, Demchuk AM, Hudon ME, Pexman JH, Hill MD, Buchan AM. Hyperdense sylvian fissure MCA “dot” sign : a CT marker of acute ischemia. Stroke. 2001;32:84–8.
Leary MC, Kidwell CS, Villablanca JP, Starkman S, Jahan R, Duckwiler GR, Gobin YP, Sykes S, Gough KJ, Ferguson K, Llanes JN, Masamed R, Tremwel M, Ovbiagele B, Vespa PM, Vinuela F, Saver JL. Validation of computed tomographic middle cerebral artery “dot” sign: an angiographic correlation study. Stroke. 2003;34:2636–40.
Shetty SK, The MCA. Dot sign. Radiology. 2006;241:315–8.
Somford DM, Nederkoorn PJ, Rutgers DR, Kappelle LJ, Mali WP, van der Grond J. Proximal and distal hyperattenuating middle cerebral artery signs at CT: different prognostic implications. Radiology. 2002;223:667–71.
Maldjian JA, Chalela J, Kasner SE, Liebeskind D, Detre JA. Automated CT segmentation and analysis for acute middle cerebral artery stroke. Am J Neuroradiol. 2001;22:1050–5.
Takahashi N, Lee Y, Tsai DY, Kinoshita T, Ouchi N, Ishii K. Computer-aided detection scheme for identification of hypoattenuation of acute stroke in unenhanced CT. Radiol Phys Technol. 2012;5:98–104.
Vapnik VN. The nature of statistical learning theory: statistics for engineering and information science. 2nd ed. New York: Springer-Verlag; 1999.
Cristianini N, Shawe-Taylor J. An introduction to support vector machines and other kernel-based learning methods. Cambridge: Cambridge University Press; 2000.
Johnson RA, Wicherm DW. Applied multivariate statistical analysis. Englewood Cliffs: Prentice Hall; 2007.
Kim EY, Lee SK, Kim DJ, Suh SH, Kim J, Heo JH, Kim DI. Detection of thrombus in acute ischemic stroke: value of thin-section noncontrast-computed tomography. Stroke. 2005;36:2745–7.
Camargo ECS, Furie KL, Singhal AB, Roccatagliata L, Cunnane ME, Halpern EF, Harris GJ, Smith WS, Gonzalez RG, Koroshetz WJ, Lev MH. Acute brain infarct: detection and delineation with ct angiographic source images versus nonenhanced CT scans. Radiology. 2007;244:541–8.
Lin K, Rapalino O, Law M, Babb JS, Siller KA, Pramanik BK. Accuracy of the Alberta stroke program early CT score during the first 3 hours of middle cerebral artery stroke: comparison of noncontrast CT, CT angiography source images, and CT perfusion. Am J Neuroradiol. 2008;29:931–6.
Nezu T, Koga M, Nakagawara J, Shiokawa Y, Yamagami H, Furui E, Kimura K, Hasegawa Y, Okada Y, Okuda S, Kario K, Naganuma M, Maeda K, Minematsu K, Toyoda K. Early ischemic change on CT versus diffusion-weighted imaging for patients with stroke receiving intravenous recombinant tissue-type plasminogen activator therapy: stroke acute management with urgent risk-factor assessment and improvement (SAMURAI) rt-PA registry. Stroke. 2011;42:2196–200.
Gadda D. A case of bilateral dense middle cerebral arteries with CT angiographic confirmation of vascular occlusion. Emerg Radiol. 2003;10:142–3.
Conflict of interest
None of the authors have any conflicts of interest associated with this study.
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Takahashi, N., Lee, Y., Tsai, DY. et al. An automated detection method for the MCA dot sign of acute stroke in unenhanced CT. Radiol Phys Technol 7, 79–88 (2014). https://doi.org/10.1007/s12194-013-0234-1
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12194-013-0234-1