3D Qualitative Ultrasound Imaging of Mammographic Density


2.1 Introduction

The breast is a sensitive part of the human female body and is placed at the front part of the body. The recent past has seen some diseases attacking the breast, hence the need to have the updated form of right medication and the latest development of having a breast treated of any tissue diseases are the qualitative ultrasound imaging that takes a closer and deeper look at the density and intensity of any growth in the mammary gland of the human body. Every female is at a risk of developing the cancerous cells, hence the need to have checkups twice per year or once per year (Zhang et al, 2016). There are many risk factors associated with the breast, hence the need to have it checked regularly by the medical teams. It is worth noting that not only women are at a risk of developing cancerous cells in their breasts, but also the men. The medical experts are in a position to modify the characteristic of the breast density as there are many triggers that could bring about the diseases in a female from the history in their family or the lifestyle that they lead which is then the most contributing factor in the recent days.

2.2 Breast Anatomy

According to O’Connell et al (2014), the research and development experts in the medical field have developed different strategies through which they have determined the breast density after being aware of the breast anatomy. Breast density is now an independent factor in determining the risk and incidence of the breast cancer in a woman. The anatomy of the breast has made it possible for the experts to lay emphasis on the breast as they have divided it into quartiles and most stating that those with more density in the upper part have more risk. A woman may not know the risk that they have in relation to their breasts and hence the expert in mammography has the task and responsibility in educating any woman that visits them for a clinical exam on the risk associated with their breasts. Information to a person is very important as they are in the know and take the right measures within their reach which they can discuss the possible screening options with their physicians. The breast density is calculated and based on the breast tissue of the attenuation by the x-ray beam on the pixel-by-pixel measurements (Wengert et al, 2015). This is then summated after all the measurements and calculations which then represent the summation of the volume of the fibro-glandular tissue, which is divided by the volumes estimated of the whole breast. The visual analysis of the breast may have some confusion or underestimated the value of the percentage of the breast.

The breast anatomy reveals that it is made of different structures which are shown by the X-rays in different methods. There is the fat part and the tissue area which is the main determinant of the density and risk of cancer cells developing. The visual view and representation of the breast is by the lexicon and divided into four quarters, which makes it easier for the breast examination. There is fat part which is less than 25% fibro-glandular tissue, the scattered tissues which makes about 25-50%, then the fibro-glandular making between 51-75% known as the heterogeneously dense and lastly the extremely dense area which makes the rest of the less than 75% fibro-glandular tissue. The visual view may not be a thorough method in determining the risk factor but the extra analysis of the breast area using more sophisticated methods. This then validates the reason to have the person undergo through another extensive and detailed test that will determine the level and risk of the diseases and the extent to which one has developed the condition.

2.3 Breast Cancer and Mammographic Density (MD) Risk Association

The medical expert’s state that those with a large breast density of more than 4- have a higher chance of developing the cancerous cells than the other females with a smaller  density translating to smaller mammary glands (Duric et al, 2013). This further necessitates the need to have checkups as the risk does not lie on the physical and visual thought of the person rather than the ultrasounds which are more developed and detailed to give any other abnormal growth in the breast.

There is a direct relationship between the radiographic images taken in a test to determine the cancerous cells. There are two components of the breast tissue as earlier aforementioned. The fat part of the breast has a low tolerance to the X-ray attenuation hence more transparent and they are darker in the radiographs (Sridharan et al, 2016). There are different qualitative and quantitative methods that determine the stage and the development of the cancer cells in the human breast. The common factor in all methods is that the latest one is the better version of the other one, hence the importance of the density of the breasts. Digitization of the images is the recent development which must ensure that all the measurements are equal in each track to ensure adequacy and high quality of the image presented to the patient. The methods used allow the expert in giving the right estimate in the measurements and as well as the findings in the image.

Breast cancer has a direct relationship with the mammographic density, which is associated with the risk of developing the cancerous malignant growth. This is because breasts with a high density affect the tissue and fat area of the breast (Sridharan et al, 2016). This is to reveal that all areas of the breast are at risk depending on their density. The examination, which reveals the density of the breast is the BI-RADS. This is to mean the Breast Imaging Reporting and Data System (BI-RADS) categories which uses some software from the computers to determine the percentage.

The percentage then determines the density of the breast and classifies it as either high risk or low risk. For people with a high risk, the mammography’s recommend the use of the US which is the Breast Ultrasound and in some cases the MRI. This is through the use of the magnetic resonance imaging which is the best option in this case (Pettersson et al, 2014).

The modern developments in the medical history are in the process of coming up with models that will increase the screening tools. The Automated Breast Ultrasound (ABUS) is the best suited method that detects the cancers within the whole breast. Scanning the whole breast provided it with the right angles unlike in the past where the breast had to be separated into different units and the images scanned in different units. This method is better placed on separating the tissue from the fibro-glandular; that is making a difference from all the other tissues.

2.4 Current Methods to Assess Mammographic Density (e.g. X-ray mammography and MRI)

The recent past has seen many developments in the ways that medical experts assess the density in the mammographic images of the breast. This is because the past had some few complaints on the quality of images that they produced while at the same making it hard for the other experts to know exactly which area had a problem. The past saw the mammography images show unspecific representation further, making it hard for an analysis (Tagliafico et al, 2013; Yaffe & Boyd, 2005). The development team had to step in and develop ways through which there would be better images and quality images reproduced making it simple and easy to give a report on the images. On the other hand, it was important to ensure that the patients left with the right information and detailed in relation to the problem detected unlike it was in the beginning where they had to come back for more tests and results. Studies conducted were to help the patient more while for the medical experts it was to make work easier for them. There was no need to have more than one abnormal finding.

Most of the developments currently are to show the images in three dimensions where the past had two dimensions. The 3D is better in view and appealing to the eyes. Instead of the conventional black and white images, it is possible to manipulate the machines and have colored which are better and detailed. It is able to separate all the tissues with the darker and brighter clusters having variations (Sak et al, 2015). There have been proposals forwarded to the research and development team on the utilization of the RVDA which measures the breast density and is better placed than all other ways of detecting the breast cancer risk. It is made easier to understand for the patient after segmenting the area of the breast while defining the fat boundary. However, if one needs to group the FCM clusters into identifiable fibro-glandular tissues and the fat tissues, they would have to opt for the automated method which gives better results. MRI and ABUS are on the other hand, preferred when determining the true volumetric density.

2.5 Quantitative Ultrasound (QUS) imaging (brief overview of physics, instrumentation).

A brief overview about the physics theory reveals that imaging has been an ongoing method of detecting the cancer cells in the human tissue. This has made it possible to develop thorough and quantitative ideas towards the images reproduced which makes it relevant for the medical experts in explaining about the condition. There are many factors related to this part which show that in order to make a valuable report in regards to the qualitative and quantitative factor when imaging, all factors must be put in place. The loss, inertial, as well as restoring parameters of a given medium can define sound waves propagation (Alsulami, 2014). The compressibility, and density of the medium tends to define the speed of sound, and the refraction of the waves from the sound occurs due to variations in the sound speed. Reflection, as well as scattering of the ultrasonic wave may occur due to spatial fluctuations more so in the compressibility or density (Alsulami, 2014). Similarly, the sound’s velocity is inversely proportional to the square root of a given medium density as shown below;

…………………………………. (i)

In the above formula, K represents compressibility, while ρ represents density.

The various interactions occuring in given biological tissues are the same as the reflection, absorption, divergence, refraction, scattering, interference, and diffraction of light. The sound pressure, as well as intensity are related as shown below;

……………………………………………. (ii)

A brief overview at the QUS method as an option for the imaging of the breast tissue reveals that it is reliable. More to that, it is detailed and it is faster than all the others. There are more calculated aspects of the QUS as from the name itself as it uses the quantitative method to arrive at the rate of the density as provided by the experts ( Alsulami 2014). The experts have to look at the length of the tissue of the patient before determining the calculated density in relation to the breast. This then determines the risk level that the patient has in regards to the results. All properties of the tissues are put in place before determining the properties of the soft tissues.

            The most common measurements that are covered in an automated and processed data is 15.4 cm by 17cm by 5 cm which are taken within one minute further aggravating the fact that many images could be captured all at once (Chen et al, 2015). The high frequency with more power has the power to allow the breast have a scan within one sweep. The image is big enough to capture all the tissues together with the detailed inner tissues which is more of a concern with the previous images that were smaller.

2.6 Previous QUS-MD Research

Since time immemorial, there have been research done in the area of the breast and in relation to cancer. This is because the disease is affecting more people in the world than had been anticipated from the beginning. It is common to see people come through the hospital ailing cancer, yet they are of a young age. This prompted the need to have a better method chosen for recognition from an early age (Wengert et al, 2015). The previous QUS-MD research in this area was not as detailed as it is presently. The research did not classify the findings into six-category classifications as it is now. The display showed poor images of the dense tissue further, making it hard to manipulate the findings to find the risk areas. The technique used also recommended the use of mammography analysis, which were a routine and one had to perform them over and over again. These repeated examinations were to ensure that they could monitor the breast and have the issues addressed in the case of the preventive inventions.

It is the recent advancement in technology that saw the rebirth of a more sophisticated and detailed QUS-MD research which revealed the changes as they are seen today. The knowledge today is interactive and allows the understanding of the triggers to the cancerous cells which then manipulate the images for the optimization and accuracy of the findings as requested and expected. There is early detection and diagnoses of the problem and in this way, patients do not suffer much from the revelation that they are sick (Sridharan et al, 2016). It is easier for treatment and the recovery process. It was also common to find that the patients felt uncomfortable during the examination process due to the poor information revealed from the QUS-MD results. A patient is more comfortable during the process through which they go under the machines for testing and during the treatment process as well.

2.7 Current Breast Anthropomorphic Phantoms (e.g. use the ACRIN Paper reference).

According to Madsen, Wendie, Ellen & Gary (2006), an introductory to this sentence reveals that currently, the breast anthropomorphic phantoms takes many forms making it easier for one to determine which method fully fits the imaging process. For instance, accessibility should be for all and the treatment availed to people. Experts recommend that the early detection has made it possible for people to get total healing. A single imaging of the breast anatomy reveals more information than it did in the past. The medical experts have found time and time again that the current phantoms have had little regards to the common person. For example, an anthropomorphic set of breast phantoms development did occur in the USA and this set was meant for imaging with the help of realistic simulations more so of the normal tissues (Madsen, Wendie, Ellen & Gary, 2006).

The current breast anthropomorphic phantoms are the ultrasonography methods which have been tried and tested making it qualify as the best breast screening method in the world. There have been different phantoms like the water-based gelatin, the non-fat components and the superior graphite. All work as they separate the subareolar region from the fatty layer tissue, making it easy and simple to detect the areas with a problem. In conclusion, it is now easier to have an ultrasound of the breast than of any other part of the body (Tagliafico et al, 2013). This is because there is a varied and detailed process discovered through the research by the medical experts. On the other hand, there are different suggestions on how more people can access the 3D ultrasound imaging of the mammographic density as it is more expensive and only a few people can afford.



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