Brain Tumor Detection using MRI: A Review of Literature Priyanka S. Jadhav Meeta Bakuli Assistant Professor, Dept. of E&TC Engg, G.H. Raisoni College of Engg. and Management, University of Pune, Pune, India PG Student, Dept.of E&TC Engg., G.H. Raisoni College of Engg. and Management, University of Pune, Pune, India Meeta.bakuli@raisoni.net jpriyanka211191@gmail.com ABSTRACT Currently, multimodal MRI images are mostly used for segmenting brain tumor image, because MRI image gives more information on tumor and its regions. But modern medical imaging research faces difficulty in detection of tumor through MRI. In detection of brain tumor using MRI, the segmentation of brain tumor is most important task. For this purpose brain tumor image is divided into number of regions. This is a important procedure but very difficult in detecting tumor. For best results it is necessary that the segmentation must be done correctly and accurately. There are various algorithms available for detection and segmentation of brain tumor. However this paper gives quick review of techniques which are developed for detection of brain tumor using MRI. At last conclusion of this paper provides direction towards advanced research studies on brain tumor detection. Keywords Brain Tumor, Magnetic Resonance Image (MRI), Preprocessing and Enhancement, Segmentation, Feature Extraction, Classification. 1. INTRODUCTION A brain tumor is nothing but a intracranial neoplasm. It occurs when abnormal cells form in the brain. According to IARC (International Agency for Research on Cancer), nearly 126000 people faces brain tumor problem per year around the world [1]. To overcome this problem more peoples are doing research on the brain tumor detection and segmentation. There are two most common tests used for the finding presence of brain tumor. First one is MRI (Magnetic Resonance Imaging) and CT (Computer tomography). There are many treatment options available which include radiation therapy surgery, chemotherapy. The selection of treatment option is based on size, grade and type of brain tumor. For improving accuracy many people go for CAD. Actually the output of computer is not a first opinion, it gives output to assist radiologist to minimize image reading time. The segmentation of brain tumor is difficult task because tumor has variety of shapes and sizes [2]. Another factor is image intensity, because tumor present at different location has different image intensities [3]. These factors make segmentation process difficult. This paper presents a review of techniques used for brain tumor detection using MRI. The paper gives conclusion with the discussion on future trends of advance research on brain segmentation. 2. OVERVIEW OF BRAIN TUMOR AND MRI 2.1 Brain Tumor All Brain tumor is nothing but abnormal mass of brain tissue which interrupts the normal functioning of brain and creates increasing pressure [2]. The brain tumor is classified according to the type, size and location. There are 120 types of brain tumor classified by World Health Organization (WHO). This classification is based on behaviour of the cell. There are two main types of tumor primary and secondary brain tumor. Primary tumor is originated in brain and secondary tumors originate from another part of body. 2.2 MR Imaging There are number of imaging techniques which are useful for the study of brain tumor such as Computed Tomography (CT), MRI (Magnetic Resonance Imaging), Single Photon Emission Computer Tomography (SPECT), Positron Emission Tomography (PET). Now a days CT and MRI techniques are most popular techniques. The contrast resolution of MRI is higher than other techniques. MRI devices can generate 3D space images. For MR imaging, patient need to placed in strong magnetic field which cause the proton align in parallel or antiparallel orientation with magnetic field. After this the spinning proton are move out of equilibrium state by introducing radio frequency pulse. The proton returns to equilibrium state when we remove or stop radio frequency pulse also it produces sinusoidal signal. This generated signal is detected by scanner and final image will be created [4]. Fig 1: MRI Scanner Cutaway 3. LITERATURE REVIEW 3.1 Image Segmentation Image segmentation is most difficult task. Differentiating the normal and abnormal area is most challenging task while segmenting image. Image segmentation is classified into three types: 1 3.1.1 Spatial Clustering There is a difference between image segmentation and image clustering. In image segmentation grouping is done in spatial domain and In image clustering it is done in measurement space. 3.1.2 Split and Merge Segmentation 4.1.3 Marker Controlled Watershed [18] Different values of threshold are selected for creating the Marker Controlled Watershed. Threshold values are highly dependent on shape and size of tumor and also on the view points (axial, coronal) of images. In split method, firstly entire image is consider and it splits into quarters. This process is repeated until a homogeneity criterion is not satisfied. In merge method, it merge or joins adjacent segments of the same object [5]. 3.1.3 Region Growing In region growing method neighbouring points are connected to each other to make the region bigger. This method is mostly depend on the selection of threshold value [5,6,7]. 4. REVIEW OF TECHNIQUES AVAILABLE FOR IMAGE SEGMENTATION The manual brain tumor segmentation is time consuming process to overcome this problem all people mostly choose automated detection and segmentation. In recent years, many methods are developed for automation of imaging, scanning, detection and segmentation. These methods mainly classified into intelligent based method and non-intelligent based method. Out of which some methods have been reviewed. 4.1 Thresholding based method It is a non-intelligent based method. In this method firstly intensity value is calculated which is called threshold which separate each class from other. This method is mainly depending on gray level intensity value. In this method the pixel having intensity greater than threshold are group into one class and remaining into other class. But the drawback of this method is there are only two classes. Also this method is not good when borders are not clear [8]. Thresholding based methods are as followed: 4.1.1 Threshold and outlier detection and Gaussian models [16] The edema region may require secondary analysis followed by treatment after the primary focus on the tumor region. The detecting technique uses a concept to detect difference between normal and abnormal space. Intensity features are used in this technique. 4.1.2 Probability level set evolution [17] The automatic method has a lower level of agreement with the human experts compared to the semi-automatic method. Only two MR images samples are used for testing and evaluate. Fig.2 Result of Thresholding for brain MRI 4.2 Region Growing based method This technique is used to extract a region of the image which is based on predefined criteria. The manually selected seed points are required for region growing and extract all pixels which are connected to initial seed. The drawback of this technique is it is sensitive to noise so this method is not sufficient for segmenting brain tumor accurately. This method is semiautomatic method because it requires manual input seed selection. Segmentation based on region growing is simpler than edge detection method. There are two methods of segmentation based on region: 4.2.1 Region Growing Steps for region growing processing: 1)Select group of seed pixels from original image [9]. 2)Select set of identical criterion and develop stopping rule. 3)For grow regions attach each seed neighbouring pixels who are having similar properties to seed pixel. 4)If no more pixels meet the criterion then control the grouping region. 4.2.2 Region Splitting and Merging In region growing we select seed point but in this method user may divide image into set of detached regions and merge that regions [10, 11] to satisfy the conditions. This method is based on quad tree data. 2 4.4 Fuzzy based method Fig.3. Brain Tumor Detection Using Region Growing based method Fuzzy logic is based on degree of membership rather than crisp membership. This algorithm helps to perform tasks related to intelligent tumor behaviours. The membership function is obtained by using intensity histogram analysis and knowledge extraction. This method gives lowest score of 71% and highest score 93%. Dunn uses fuzzy c-mean (FCM) clustering algorithm for image segmentation [12].FCM is implemented by several researchers. In clustering most important task is finding cluster to classify pixels [13]. FCM algorithm is fast, unsupervised and simpler than other algorithm. Jaffar introduce a FCM using curvelet transform to remove the noise [14]. 4.4.1 Fuzzy models Image Fusion [22] 4.3 Neural Network based method This method uses a model which consist neurons and weighed connection between them. To obtain the values of weights i.e. coefficients requires training. Several types of network used for image segmentation for eg. Multilayer Perceptron (MLP). The earliest application of MLP are trained the neural network using known diagnostic image. Detection and visualization of brain tumor can be done by using unsupervised learnining artificial neural network. The hierarchical Self Organizing Map (HSOM) is a modified version of SOM. 4.3.1 ANN using canny edge detection adaptive thresholding [20] MRI brain represents a healthy brain or a tumor brain. In this paper two types of input features are used: canny edge detection and adaptive thresholding 4.3.2 Probability Discrete wavelet transforms (DWT) back propagation (BPNN) [21] This paper uses hybrid classifier to distinguish normal and abnormal brain This method had good accuracy in classifying both training and testing images. This method may be used for MRI images with other contrast mechanisms like TI-weighted, protondensity weighted and diffusion-weighted MRIs. The proposed algorithm consists of: the registration of multispectral MR images, the creation of fuzzy models describing the characteristics of tumor, the fusion based on fuzzy fusion operators and the adjustment by fuzzy region growing based on fuzzy connecting. Using linear image registration tool for evaluate the proposed method. 4.4.2 Histogram- based Fuzzy c mean smoothen the boundaries [23] The FSL library tool based software was compared with the performance of the proposed algorithm. It is considered to be a good candidate for fully automatic MRI analysis systems. Because of the fully automated nature of the algorithm with no human intervention, along with lesser number of iterations taken 4.4.3 Fuzzy C Means [24] Generalized spatial fuzzy c-means (CSFCM) algorithm which possesses both pixel attributes and spatial local information that is weighted in correspondence with neighbor elements based on their distance attributes. This has the potentiality to improve segmentation performance tremendously. This improves the segmentation performance dramatically. Poor contrast, noise and non-uniform intensity variation can affect the results. the Fig.4. Brain Tumor Detection Using Neural Network 3 The thresholds taken from the EM output are utilized to adaptively adjusting the rate of expansion in the segmented area. This increases the classification quality. Fig.6. Brain Tumor Detection Using Hybrid based method Fig.5. Brain Tumor Detection Using Fuzzy based method 4.5 Hybrid based technique Different methods of machine learning algorithm are combined to form hybrid system. It gives better solution to a problem, which is not given by single method. Jzau-sheng uses global histogram of images and constructed neurons. Nandita proposed a method in which input is fuzzy and output is crisp value [15]. But the intensity values are not fix so that there is a difficulty for ascertaining generalized efficiency. 4.5.1 ANN fuzzy logic [25] Adaptive Neuro-Fuzzy inference systems (ANFIS) for MR brain tumor classification developed in this research and a comprehensive feature set and fuzzy rules are selected to classify an abnormal image to the corresponding tumor type The classification accuracy of ANFIS is comparatively higher than the fuzzy and neural classifiers. The convergence time period of ANFIS is ten times better than the neural and the fuzzy classifier. (DWT) principal component analysis (PCA), (BPANN) k nearest neighbor classifier (KNN) [26] 4.5.2 classify subjects as normal or abnormal MRI human images, A classification with a success of 97% by FP-ANN and 98% has been obtained by k-NN, This research developed two hybrid techniques, DWT + PCA + FP-ANN and DWT + PCA +k-NN to classify the human brain MR images. Without any tumor detection. 4.5.3 Neural network, adaptive adjustment [27] The EM is initially used in brain MR image histogram for estimating the distribution of parameters for WM, GM and CSF regions. These estimated parameters work as fitness function for tissue classification. 5. CONCLUSION Proper segmentation method is required for accurate diagnosis of brain tumor detection and segmentation. Currently various slices of many images provide information for planning and treatment purpose. In this paper, we reviewed some of recent research work done on brain tumor detection and segmentation. By analyzing literature we conclude that the automation of brain tumor detection and segmentation using MRI is one of the most active research area but currently there is no method which is accepted clinically. 6. REFERENCES [1] Ferlay J, Shin HR, Bray F, Forman D, Mathers C and Parkin DM, GLOBOCAN 2008 v2.0, Cancer Incidence and Mortality Worldwide, International Agency for Research on Cancer, Lyon, France, 2010. http://globocan.iarc.fr, Accessed on: November 13, 2011. [2] Louis D.N., Ohgaki H., Wiestler O.D, Cavenee W.K. (Eds.), WHO Classification of Tumors of the Central Nervous System, International Agency for Research on Cancer (IARC), Lyon, France, 2007. [3] http://www.radiologyassistant.nl/, Accessed on: January, 12, 2012. [4] A. O Rodriguez, Principles of Magnetic Resonance Imaging, Revista Mexicana de Fisica, Vol. 50, No. 3, 2004, pp. 272-286. [5] Jain R. et al, Machine Vision, McGraw-Hill, Inc. 1995. [6] Sonka, M., Hlavac, V., and Boyle, R., “Image Processing, Analysis, and Machine Vision”, Brooks / Cole Publishing Company, 1998. [7] Zucker, S. W., “Region growing: Childhood and adolescence”, Computer Graphics and Image Processing, 1976, 5, 382-399. [8] Sezgin M. and Sankur B., Survey over image thresholding techniques and quantitative performance evaluation, Journal of Electronic Imaging, Vol. 13, No. 1, Jan. 2004, pp. 146– 165. 4 [9] K. K. Singh, A. Singh, “A Study of Image Segmentation Algorithms for Different Types of Images”, International Journal of Computer Science Issues, Vol. 7, Issue 5, 2010. images." Computer Engineering and Systems (ICCES), 2010 International Conference on.IEEE, 2010. [10] W. X. Kang, Q. Q. Yang, R. R. Liang, “The Comparative Research on Image Segmentation Algorithms”, IEEE Conference on ETCS, pp. 703-707, 2009. [21] Zhang, Yudong, Zhengchao Dong, Lenan Wu, and Shuihua Wang. "A hybrid method for MRI brain image classification." Expert Systems with Applications38, no. 8 (2011): 10049- 10053. [11] Zhang, Y. J, An Overview of Image and Video Segmentation in the last 40 years, Proceedings of the 6thInternational Symposium on Signal Processing and Its Applications, pp. 144-151, 2001. [22] Dou, W., Ruan, S., Chen, Y., Bloyet, D., & Constans, J. M. (2007). A framework of fuzzy information fusion for the segmentation of brain tumor tissues on MR images. Image and vision Computing, 25(2), 164-171. [12] J. C. Dunn, A Fuzzy Relative of the ISODATA Process and Its Use in Detecting Compact Well-Separated Clusters, Journal of Cybernetics, Vol. 3, No.3, 1973, pp. 32-57. [23] Sikka, Karan, Nitesh Sinha, Pankaj K. Singh, and Amit K. Mishra. "A fully automated algorithm under modified FCM framework for improved brain MR image segmentation." Magnetic Resonance Imaging 27, no. 7 (2009): 994-1004. [13] Dehariya, Vinod Kumar, Shailendra Kumar Shrivastava, and R. C. Jain. "Clustering of Image Data Set Using K-Means and Fuzzy KMeans Algorithms."Computational Intelligence and Communication Networks (CICN), 2010 International Conference on. IEEE, 2010. [14] M. Arfan Jaffar, Quratulain, and Tae Sun Choi, Tumor Detection From Enhanced Magnetic Resonance Imaging Using Fuzzy Curvelet, Microscopy Research and Technique, Wiley Online Library, Vol. 75, No. 6, April 2012, pp. 499504. [15] Nandita Pradhan and A.K. Sinha, Fuzzy ANN Based Detection and Analysis of Pathological and Healthy Tissues in FLAIR Magnetic Resonance Images of Brain, international Journal of Information Technology and Knowledge Management, Vol. 4, No. 2, July- Dec. 2011, pp. 471-476. [16] Prastawa, Marcel, and Guido Gerig. "Automatic MS lesion segmentation by outlier detection and information theoretic region partitioning." Grand Challenge Work.: Mult. Scler.Lesion Segm. Challenge (2008): 1-8. [24] Van Lung, H., & Kim, J. M. (2009, August).A generalized spatial fuzzy c-means algorithm for medical image segmentation. In Fuzzy Systems, 2009. FUZZ - IEEE 2009. IEEE International Conference on (pp. 409-414). IEEE. [25] Hemanth, D. Jude, C. K. Vijila, and J. Anitha. "Application of Neuro-Fuzzy Model for MR Brain Tumor Image Classification." Int J Biomed Imaging 16 (2009): 95102. [26] El-Dahshan, El-Sayed Ahmed, Tamer Hosny, and AbdelBadeeh M. Salem. "Hybrid intelligent techniques for MRI brain images classification." Digital Signal Processing 20.2 (2010): 433-441. [27] Fu, J. C., Chen, C. C., Chai, J. W., Wong, S. T., & Li, I. C. (2010). Image segmentation by EM-based adaptive pulse coupled neural networks in brain magnetic resonance imaging. Computerized Medical Imaging and Graphics, 34(4), 308-320. [17] Dubey, R. B., Hanmandlu, M., Gupta, S. K., & Gupta, S. K. (2009). Semi-automatic segmentation of MRI Brain tumor. ICGSTGVIP Journal, 9(4), 33-40. [18] Singh, Laxman, R. B. Dubey, Z. A. Jaffery, and Z. Zaheeruddin. "Segmentation and Characterization of Brain Tumor from MR Images". In Advances in Recent Technologies in Communication and Computing, 2009. ARTCom'09. International Conference on, pp. 815-819. IEEE, 2009. [19] Amruta, A., Abhijeet Gole, and Yogesh Karunakar. "A systematic algorithm for 3-D reconstruction of MRI based brain tumors using morphological operators and bicubic interpolation." Computer Technology and Development (ICCTD), 2010 2nd International Conference on. IEEE, 2010. [20] Badran, Ehab F., Esraa Galal Mahmoud, and Nadder Hamdy. "An algorithm for detecting brain tumors in MRI 5