Muhammad Ali Shoaib, Md Belayet Hossain, Yan Chai Hum, Joon Huang Chuah, Maheza Irna Mohd Salim and Khin Wee Lai * Pages 739 - 751 ( 13 )
Background: Ultrasound (US) imaging can be a convenient and reliable substitute for magnetic resonance imaging in the investigation or screening of articular cartilage injury. However, US images suffer from two main impediments, i.e., low contrast ratio and presence of speckle noise.
Aims: A variation of anisotropic diffusion is proposed that can reduce speckle noise without compromising the image quality of the edges and other important details.
Methods: For this technique, four gradient thresholds were adopted instead of one. A new diffusivity function that preserves the edge of the resultant image is also proposed. To automatically terminate the iterative procedures, the Mean Absolute Error as its stopping criterion was implemented.
Results: Numerical results obtained by simulations unanimously indicate that the proposed method outperforms conventional speckle reduction techniques. Nevertheless, this preliminary study has been conducted based on a small number of asymptomatic subjects.
Conclusion: Future work must investigate the feasibility of this method in a large cohort and its clinical validity through testing subjects with a symptomatic cartilage injury.
Ultrasound, osteoarthritis, anisotropic diffusion, diffusivity function, gradients, flow function, edge preservation, speckle noise.
Department of Biomedical Engineering, Faculty of Engineering, University Malaya, 50603, Kuala Lumpur, School of Information Technology, Deakin University, Melbourne, Department of Mechatronics and Biomedical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Bandar Sungai Long, Cheras, Kajang 43000, Selangor, Darul Ehsan, VIP Research Lab, Department of Electrical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Department of Biomedical Engineering, Faculty of Engineering, University Malaya, 50603, Kuala Lumpur