Medical ultrasonography is an ultrasound wave based imaging technique used to scan internal body structures and is non-invasive, portable, accurate and economical. Due to such characteristics, this imaging modality has gained high importance in diagnostic field of radiology. However, a major limitation of ultrasound images is the presence of locally correlated multiplicative speckle noise that degrades the image quality. The speckle noise is generated by interfering echoes of a transmitted waveform at the time of acquisition. The overlapping of sound echoes approaching with random time periods and amplitudes yields complicated interfering arrangement called speckle noise [1]. Speckle noise is likely to create uncertainty and may conceal vital clinical facts, thus diverting the opinion of radiologists. Therefore, there is a need of despeckling technique, which is capable to restore an image without affecting important features and texture of the original image so as to assist the radiologists in making a more accurate diagnostic decision.
The main focus in this work is to develop a versatile despeckling technique to improve the quality of medical ultrasound images for better clinical diagnosis. The proposed technique is a variant of the recently published technique by Sudha et al. [2].The innovative aspects of the proposed technique are three-fold: (a) used curvelets to efficiently separate edges and noise, (b) revised criteria for defining the weights of window model used to calculate the weighted variance by exploiting the intra-band dependencies present in the curvelet coefficients, and (c) devised a window tuner to help radiologists to control the degree of smoothing of output image.
The paper is organized as follows. A brie...
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...ne in curvelets than denoising using wavelets [28]. Hard thresholding has been used to modify curvelet coefficients [ 28-32].
The literature survey reveals that very little work has been reported for despeckling using curvelets [29]-[32]. None of these techniques [29]-[32], take into account the directional intra-band dependencies of curvelet coefficients for calculation of the threshold, which are very important to make the threshold adaptive to signal variation. Despeckling is always a trade-off between noise suppression and loss of information, something that experts are very concerned about. It is therefore attractive to keep as much of important information as possible. In this paper, an attempt has been made to design a scale adaptive threshold despeckling technique in the curvelet domain for recovering an image without losing the fine curved vital details.
Diagnostic medical sonography is a profession where sonographers direct high-frequency sound waves into a patient’s body through the use of specific equipment to diagnose or monitor a patient’s medical condition. As described by the Bureau of Labor Statistics, this examination is referred to as an ultrasound, sonogram, or echocardiogram. The high-frequency sound waves emitted from the handheld device, called a transducer, bounce back creating an echo and therefore produce an image that can be viewed on the sonographers computer screen. This image provides the sonographer and physician with an internal image of the patient’s body that will be used in the diagnosis. The most familiar use of ultrasound is used in monitoring pregnancies and is provided by obstetric and gynecologic sonographers, who also provide imaging of the female reproductive system. Other types of sonography include; abdominal sonography, breast sonography, musculoskeletal sonography, neurosonography and cardiovascular sonography. Due to the vast nature of uses in sonography, most professionals study one field that they choose to specialize in. Diagnostic medical sonography is a rapidly growing field because of the increase in medical advances. The area of Cleveland, Ohio has continued to rise in the medical field with great strides, providing better career prospects with the availability of numerous employment positions.
waves were reflected back to the transducer as they crossed interfaces of different acoustic impedance. More simply, the ultrasound bounced off the
Diagnostic medical sonography is where sonographer coordinate high-recurrence sound waves into a patient's body using particular gear to analyze or screen a patient's restorative condition. As portrayed by the Bureau of Labor Statistics, some other branches of diagnostic sonography consist of: vascular technologist, also called diagnostic imaging workers, operate special imaging equipment to create images or to conduct tests. The images and test results help physicians assess and diagnose medical conditions.
Many wonder how do ultrasounds truly work. Ultrasounds are actually more complex than what they seem to be. First, the ultrasound machine transmits high-frequency sound pulses into your body using a probe, and then sound waves travel into your body and hit a boundary between tissues (Freudenrich, 2011). An example of this would be between fluid and soft tissue and soft tissue and bone. After that, some of the sound waves get reflected back to the probe, while some travel on further until they reach another boundary and get reflected, the reflected waves are then picked up by the probe and relayed to the machine. The machine calculates the distance from the probe to the tissue or organ using the speed of sound in tissue and the time of the each echo's return. Finally, the machine displays the distances and intensities of the echoes on the screen, forming a two dimensional image like the one shown below (Freudenrich, 2011).
tends to be less expensive than most other imaging methods such as CT or MRI’s. It is important for the patient to know how this procedure works and the risks involved in order to make a decision whether or not to have the procedure done. Luckily, sonography is considered one of the more harmless methods.
The dream that I most desire in life is to become a Diagnostic Medical Sonographer. I’ve always had an interest in the inner workings of the human body, but I also value life, and care for others, and my happiness is the happiness of others. Although this career has its bumps on the road just to see mothers face light up when they see the image of their unborn baby is such a breath taking experience. This all originated from going to one of my sisters’ ultrasound appointment that I ended up going to all my sisters’ ultrasound appointments. I believe becoming a diagnostic medical sonographer is something I can do because I have what it takes. Diagnostic medical sonographer is imaging modality that can work in conjunction with other imaging modalities
Dubey, R.B., et al. “The Current CAD and PACS Technologies in Medical Imaging.” International Journal of Applied Engineering Research 4.8 (2009): 1439-1456. Academic Search Complete. Web. 20 Feb. 2011.
In summary, the medical imaging technology of ultrasound is founded on the world of physics. As we understand more and more about waves and how they functions, ultrasound imaging capabilities expand, allowing for the increasingly accurate diagnostic of medical problems.
Being able to identify lumps, swelling, tissue damage, cysts, and the overwhelming news of the sex of a baby all have something in common, an ultrasound. Swelling of the spleen, kidney stones, blood clots, aneurysms, cancer and so much more can be identified through the works of an ultrasound’s imaging technique. Ultrasound involves many concepts, procedures, and careers. The amount of medical possibilities involved with ultrasounds is useful in major medical diagnostics. The field of ultrasounds and career opportunities are widely growing. As medical careers flourish, needs for technicians in many fields of medicine are increasing. Instead of a doctor choosing complex and risky surgery to find out problems within the body, they can now choose a safer path; the ultrasound path. Patient’s history and physical evaluation are building blocks to diagnostics but ultrasounds are much greater. They are powerful tools used to see beyond the skin into the depths of a person’s body. What ultrasounds are, what types there are, and what they are used for, and the education and careers available are the major themes found in research on the subject. Knowledge of ultrasound and its background may help one decide what career is best for them. Understanding the wide array of diagnostic tests and their uses are essential to figuring out what a career as a sonographer entails and the type of education that is needed. Because there are plenty of possibilities for specializing with different technologies, there is a wide variety of job opportunities in the medical imaging career. The call for ultrasound’s assistance opens new paths in future high-quality careers.
Ultrasound Technicians are very valuable in the world of health care. Also known as Diagnostic Medical Sonographer, an Ultrasound Technician uses special machines and equipment that operates on sound waves to determine or diagnose medical problems for patients. There are specializations within this field in which some individuals explore. For instance, areas of specialization includes but not limited to; pregnancy, heart health, gynecology, and abdominal sonography. Although each specializing branch has its own distinctive function, they all involve probing the body to facilitate doctors with diagnoses.
Lyons et al. [6] Classifying facial attributes using a 2-D Gabor wavelet representation and discriminant analysis used a set of multi scale, multi orientation Gabor filters to transform the images first. The Gabor coef...
After the initial pre processing steps of smoothening and removal of noise, the edge strength is calculated by taking the gradient of the image. For the purpose of edge detection in an image, the Sobel operator first performs a 2-D spatial gradient measurement with the help of convolution masks. The convolution masks used is of the size 3X3, where one is used to calculate the horizontal gradient(Gx) while the other is used to calculate the vertical gradient(Gy). Then, the approximate absolute edge strength can be calculated at each point. The masks used for the convolution process is as shown
Rumack, C. M., Wilson, S. R., & Charboneau, J. W. (2005). Diagnostic ultrasound (3rd ed.). St. Louis: Elsevier Mosby.
Images of human anatomy have been around for more than 500 years now. From the sketches created by Leonardo da Vinci, to the modern day Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) scan, images have played a great role in medicine. Evolution in medical imaging brought together people from various disciplines such as Biology, Physics, Chemistry and Mathematics, a collaboration which has further contributed to healthcare as a whole. Modern day imaging improves medical workflows by facilitating a non-invasive insight into human body, accurate and timely diagnostics, and persistence of an analysis.
Initially, my area of interest was directed towards diagnostic sonography, however, this area of study was not