Imaging of Malignant Breast Disease - Essay Example

? Imaging of Malignant Breast Disease By of 2619 Words Introduction Imaging is among the many technologies that have helped improve medical service delivery in recent times. In fact, the number of imaging modalities has steadily risen in contemporary medical practices, making imaging a rather integral part of the health care industry. This assertion is evidenced by the many health facilities that allocate huge financial and human resources to purchase the latest and the most sophisticated imaging machines and professionals to operate these machines. Among the services encompassed in medical imaging are radiology, radiography, biomedical engineering, performed by radiologists, radiographers, medical physicists and biomedical engineers (O'Connor & Hruska, 2009). Although theses techniques and professionals may appear distinct, they need and support one another with the professionals often working as a team for the maximisation of output and the delivery of quality services. To achieve their objectives, there are certain features that have to be inherent in medical imaging services offered by these techniques. First, imaging services ought to be designed and developed as part of national health care systems to address the health needs of the target population and aligned with the socioeconomic needs and structure of the targeted population or neighbourhood (O'Connor & Hruska, 2009). Second, proper government regulation of the acquisition and use of imaging technologies and modalities should be ensured with the right national and international standards applied and observed by stakeholders. Third, imaging services should also be offered at the right levels of health care systems to ovoid discrimination in service provision. In addition, appropriate therapeutic capabilities, equipment, infrastructure and procedures must be instituted for imaging services to be effective in a health care system or facility. What is more, there should be a constant supply of well trained technical, engineering and medical staff. Ethically and professionally, regulations and measurements of radiation protection standards and regular and sufficient supply of clean water, electric power, spare parts and consumables should be ensured (O'Connor & Hruska, 2009). That diagnostic imaging is critical in the medical fraternity is a rather obvious assertion if the widespread use of X-ray based examinations and ultrasonography is anything to go by. As a matter of fact, every health care setting, its nature, size or target patients notwithstanding, needs an imaging technology. Additionally, all types of health services need diagnostic imaging, be they curative medicine, preventive medicine or decision making processes in health care delivery. Despite the fact that a professional may apply the medical-clinical judgment to treat a condition, diagnostic imaging services are handy and more effective in the confirmation and the correct assessment and documentation of diseases and their processes, thus making judgment quite accurate and assuring disease response to treatment (O'Connor & Hruska, 2009). Due to the recognition of these vital roles of diagnostic imaging, the medical technology industry is currently awash with increasingly resourceful, newer, more advanced and better imaging technology, implying the importance and the use of diagnostic imaging health care has increased considerably in recent times. The reason for this increased use of diagnostic imaging is its roles in disease exclusion, proof of pathological processes to be treated and the tracing of already diagnosed conditions (O'Connor & Hruska, 2009). Malignant diseases are among the types of diseases that have benefitted from diagnostic imaging. This paper thus explores the diagnostic imaging modalities applied in the imaging of malignant breast disease. Imaging of Malignant Breast Disease Malignant breast disease ranks alongside other major killers such as cancer as the most common causes of death in different populations across the globe. Since tumors are chief type of breast lesions and the distinction of benign and malignant tumors of the breast has been marred by clinical confusion, it has become necessary and an absolute diagnosis to eliminate the existence of either tumor. One purpose of imaging would be to establish any breast abnormality. In this regard, a technology such as mammography is often used to screen for breast malignancy. However, there are several imaging techniques that may be used depending on the circumstances surrounding a breast disease. These techniques include computerized tomography, magnetic resonance imaging, ultrasonography and nuclear medicine procedures. All these modalities of medical/diagnostic imaging are useful in the identification of malignant abnormalities in breast tissues. Mammography Film-screen mammography is a diagnostic imaging tool that has been in use for quite sometime considering is was first used in the 1970s for diagnosing breast cancer. Since then, this technology has replaced clinical and self-examination as methods of detecting breast malignancies. Unfortunately for mammography but fortunately for the entire medical industry, more sophisticated and effective imaging techniques have been discovered and their use expanded in recent times, diminishing mammography’s use in breast malignancy diagnosis. These more advanced techniques include MRI, and positron emission tomography (PET), ultrasonography and CT. Nonetheless, mammography continues to be the standard and first-option radiology tool for the screening and diagnosis of breast malignancies given that its technology has also kept abreast with the latest imaging modalities as evidenced by the use of digital mammography in which digital sensors are used instead of the X-ray film. Consequently, mammography’s accuracy of diagnosis has also increased. The other advantage of mammography over other diagnostic imaging techniques is its cost effectiveness, which makes it widely available and accessible. Mammography is used for cancer screening and diagnosis. Thus, there is the screening mammography that is often applied on people with no complaints of symptoms of cancer for the purposes of early detection of malignancies to help reduce cancer morbidity and mortality. It is worth noting that screening mammography is not necessarily applied to cure breast malignancies. One weakness of mammography is that there is a 20%-30% false-negative rate since breast tumors not characterised by or associated with calcifications and subtle masses are quite difficult to diagnose with mammography in certain cases. Mammography also has considerable negative effects such as unnecessary biopsy of probably benign lesions, patient anxiety about mammography and the possible findings. Nonetheless, mammography use in the screening and diagnosis of malignancies in breast tissues has yielded reduced mortality rates in screened people and the subsequent global acceptance of the technique as a preventive health care tool. As mentioned, the other use of mammography is in the diagnosis of breast malignancies in people with cancer symptoms such as lumps that may have been detected during clinical or self examinations. Further, mammography could be used to test people who are suspicious about the results of their screening mammography. Because of the advances in malignancy diagnosis technology, mammography is currently being considered an initial test in the detection of breast cancer. One reason for this is the disadvantage of decreased sensitivity to mammography among women with dense breasts. Although the standard screening mammography is common due to its cost effectiveness, the significantly advanced digital method, which uses computers, has improved sensitivity and clarity of breast images. Moreover, the digital method has special designs of image (digital) detectors, which change the X-ray images into digital images, creating a high-resolution image on the computer monitors (Brusin, 2006). In general, the digital mammography has some advantages including a higher contrast resolution and its ability to allow for electronic transmission and storage of images in a less space compared to that required in film-screen mammography. Third, the images of digital mammography can be manipulated to improve visualisation for the clear viewing of faint structures and calcifications (Brusin, 2006). Digital mammography also reduces the time wasted during film development in the film-screening technique. Finally, the digital approach to mammography uses a lower dose of radiation compared to the film-screening mammography. Included among the disadvantages of digital mammography are cost, unavailability, inaccessibility, numerous studies, training and little difference in cancer detection /similar accuracies in some cases (Brusin, 2006). How Mammography Works In its fundamental working, a mammogram is an x-ray focused on imaging a breast. Since the tissues of the breast are rather dense, there is need to design a mammography unit that would increase the quality of the resultant images without increasing radiation to harmful levels. To further minimize the effects of radiation, only the breast tissues to be screened or diagnosed are exposed to the x-rays. Thus, a paddle is added to the mammogram unit to compress the breast tissues against the plat with the intention of achieving even images at different angles (Humphrey et al., 2002). Using the conventional x-ray methods or digital means, the images of the target tissues are then produced on a film and then stored. In case of digital mammography, these images should be stored in a computer or other electronic storage devices. Since mammograms assist in the early detection of breast abnormalities in people without symptoms, it enhances the chances of treatment and recovery in case a malignant tissue is detected (Humphrey et al., 2002). In the performance of a mammogram, the client is required to sit in the front of the mammography unit, which is rectangular and specially designed for breast imaging. With the breast well positioned on the platform, the plastic paddle then compresses the breast into position onto the platform. This compressed breast is the best for imaging since the breast evens out to allow the tissues to be imaged at the same thickness. Additionally, this compression lowers the quantity of radiation required to completely penetrate the breast tissues, thus reducing the amount of scatter radiation to the rest of the body (Humphrey et al., 2002). Although this compression is generally comfortable, it may be uneasy for people with sensitive breasts. It is thus recommended that people, especially women with sensitive breast plan for mammography when their breasts are least tender. Magnetic Resonance Imaging Magnetic Resonance Imaging (MRI) is the other commonly used breast malignancy imaging modality. This technique has been especially widespread in the last twenty years in which it has been extensively used in the detection, diagnosis, and staging of breast malignancy. Although MRI technology has largely improved in recent times, it has not been well established as the routine procedure for malignancy screening. This scenario exists despite the accuracy and increased sensitivity associated with MRI in the detection of breast cancer. One disadvantage of MRI has been identified as its limited specificity more so with regards to the appearance of benign and malignant lesions. However, the method has been shown to be just about 100% sensitive in the detection of invasive breast carcinomas (Orel & Schnall, 2001). To reduce the effects of MRI on a patient’s respiratory motion and to improve image quality and resolution, breast MRI is often performed in horizontal position. Often used in MRI is an intravenous contrast agent such as 0.1 mol gadolinium per kilogram of weight, which is considered vital in the identification of breast cancers and distinguishing malignant and benign tumors (Orel & Schnall, 2001). Also included in an MRI procedure is a biopsy of the lesion to help in the differentiation of malignant and non-malignant breast cancers. To this effect, there is a dedicated MRI-guided machine to be used to access the medial side of the breast for purposes of minimizing the requirement that a patient is moved from an MRI to a biopsy room (Orel & Schnall, 2001). The main types of MRI-guided biopsy are the percutaneous biopsy, ultrasound and the stereotactic guidance biopsy. However, the former has been established to be more expensive than the latter two. Although the indications for MRI of the breast are yet to fully evolve be established, the technique is highly recommended for at-risk women based on family history of BRCA1 and BRCA genetic mutations that are associated with 5% to 6% breast cancer chances (Orel & Schnall, 2001). The MRI technique is always indicated as an add-on to either ultrasonography or mammography in the detection and diagnosis of breast malignancies and for imprecise findings on a mammogram especially when invasive carcinoma and Ductal carcinoma in situ (DCIS) are suspected. The other interesting areas of application for MRI are in the planning of preoperative treatment for a patient to show the extent of multifocal and multi-centric tumors and invasive lobular cancers and tumors with extensive intra-ductal components (Orel & Schnall, 2001). Additionally, MRI has uses in the detection of occult disease in the contra-lateral breast for those just diagnosed with breast carcinoma. MRI is however not recommended for people who cannot get to a prone position and those suffering from claustrophobia, and those on pacemakers (Orel & Schnall, 2001). The two core disadvantages of MRI are high cost and time resources required to perform the procedures. Ultrasonography Ultrasonography is the other common diagnostic method used in medical imaging. As a matter of fact, ultrasonography has supplemented the diagnosis of malignant breast since the early parts of the 1950s (Oksava & Iivanainen, 2011). Although the ultrasonography technologies of that period were rather limited and crude, this situation has since been reversed and the approach is now regularly used to diagnose breast cancer. This regular use of ultrasonography to detect cancer gathered momentum in the mid 1980s when prone position- and supine-automated ultrasonography breast cancers were developed (Oksava & Iivanainen, 2011). In addition, the combined use of ultrasonography and mammography during this period also played a crucial role in the emergence of ultrasonography in breast cancer imaging in the mid 1980s. Nevertheless, ultrasonography is yet to be as established as other approaches such as mammography in as a routine and valuable breast cancer imaging technique. The main reason for this situation facing ultrasonography is the techniques’ limited capacity to depict micro-calcifications, which are an indication of potential malignancy. Second, the method has a limited capacity to distinguish between benign and malignant tissues. Consequent to these disadvantages, ultrasonography is mainly used as a follow up to the diagnosis of a screening of an abnormal mammogram (Oksava & Iivanainen, 2011). The other use of ultrasonography is its use in image-guided biopsy. Among the advantages of this technique are real-time continuous observations of needle passage, speed and patient comfort. The other strengths of the technique are wide availability, ability to reveal organ structures, relatively cheap compared to MRI and computerised X-ray tomography and ease of portability. Additionally, the use of ionisation radiation, ease of accessibility and relatively low cost are the other advantages. As a diagnostic tool for malignancy, ultrasonography is based on the visualisation of subcutaneous structures/organs of the body including vessels, lesions, tendons, muscles, joints, and other internal body organs. From the term ‘ultrasound,; which refers to sound frequencies above the normal range the human hearing is accustomed to (20kHz), it is clear that diagnostic ultrasonography uses frequencies above the 20kHz, which is typically between 2 and 18 MHz (Oksava & Iivanainen, 2011). Ultrasonography is used in breast cancer diagnosis and therapeutic procedures. In that latter use, ultrasound is used to give direction on the right interventions such as biopsy for cancer patients. The professionals who perform ultrasonography and other types of sonographies are referred to as Sonographers. These professionals perform scans that are then interpreted and applied by physicians referred to as radiologists, specialists in various medical imaging modalities (Oksava & Iivanainen, 2011). However, cardiologists are also able to interpret and apply these kinds of scans. Conclusion Medical technological advances have played a rather crucial role in improving the screening and diagnosis of breast malignancies in the past and current times. These methods of diagnosis of breast malignancy include mammography, MRI, ultrasonography, Positron Emission Tomography and Nuclear Breast Imaging among others. It is worth noting that each of these modalities of breast cancer imaging has its weaknesses and strengths and it is imperative that these are considered before a modality is opted for by a patient or his/her loved ones. For instance, the disadvantages of digital mammography include cost, unavailability, inaccessibility, numerous studies and training needs while the advantages of ultrasonography are real-time continuous observations of needle passage, speed and patient comfort. References Brusin, J. H. (2006) “Digital Mammography: An Update.” Radiology Technology, 81(1): 226. Humphrey, L. L., Helfand, M., Chan, B. K., and Woolf, S. H. (2002) “Breast cancer screening: a summary of the evidence for the U.S. Preventive Services Task Force.” Ann Intern Med, 137(5 Part 1): 347. O'Connor, M., and Hruska, C. (2009). "Molecular Breast Imaging". Expert Review of Anticancer Therapy, 9(8): 1073. Oksava, K., and Iivanainen, M. (2011) “Handedness in the Helsinki Ultrasound Trial". Ultrasound in Obstetrics & Gynecology, 37(6):642. Orel, S. G, and Schnall, M. D. (2001) “MRI Imaging of the Breast for Detection, Diagnosis and Staging of Breast Cancer.” Radiology, 220: 13. Read More