Essay on Advanced Medical Imaging Modalities Used in Breast Imaging

Breast cancer is among the leading deadly disease across the world. It is the ultimate cancer incidence among women. Although breast cancer is associated with a high death rate, the infection can be detected, diagnosed, and treated if identified early enough. Historically, medical professionals could see the possibility of breast cancer by feeling a lump on the breast. However, a lump could only be detected after a long period of existing cancer cells in the breast, a minimum of stage 2 cancer; hence it became difficult to treat. As such, methods to investigate early breast cancer cells necessitated the introduction of breast imaging. Traditional imaging modalities include mammography, Computed Tomography (CT), Ultrasound, Position Emission Tomography (PET), and Magnetic Resonance Imaging (MRI). Advanced medical imaging modalities include thermography, microwave imaging, optical imaging, and Electrical Impedance Tomography (EIT).¹ This study aims at describing the advanced imaging modalities, highlighting their advantages and disadvantages.

Electrical impedance tomography

EIT is a modern screening technique that involves low-frequency electric currents to examine the variations in electrical conductivity between body surfaces. In other words, EIT involves placing electrodes on a body part and passing a current across the body part to establish the voltages induced on the electrodes. The conductivity variations are represented in the form of gray images. EIT equipment can be used for screening bed-ridden patients. Although EIT is used primarily for physiologic processes such as cardiac output, blood flow, and gastric emptying, current medical advances have adopted EIT as an imaging tool for detecting breast cancer. The benefits of EIT include; the screening process is non-radioactive and non-invasive hence has minimal side effects. Besides, EIT is inexpensive; thus, many women with breast cancer can afford the imaging costs. However, EIT images have a poor spatial resolution, making it hard to quickly detect a breast problem.

Thermography

This imaging test detects heat and blood flow patterns in body tissues using an infrared camera. Since cancer cells require blood rich in oxygen to survive and multiply, the blood flow and temperature around the body tissue with cancer cells is high. Thermogram images show the areas within a body tissue where the temperature is high alongside increased blood flow. According to Anandhamala (2018), Thermography applications consist of dentistry, neurology, pain management, veterinary science, orthopedics, foot ulcer, and breast cancer screening. Thermography has both benefits and shortcomings.² The advantages include; the images can be used to detect breast cancer even at its early stage. The technique is very effective when screening dense breasts, and the thermogram images are non-invasive and non-radioactive. On the other hand, thermography imaging tests are highly affected by room temperature, producing unreliable results. The screening process is often faced with high false positives and low negatives specificities, thus inaccurate.

Optical imaging

This imaging technique uses light and special photons to examine the interior surfaces of body organs, cells, and tissues. Optical imaging can be described using two approaches: Diffuse Optical Imaging (DOI) and ballistic imaging. DOI uses fluorescence and near-infrared spectroscopy to investigate the variations in the oxygenated and deoxygenated hemoglobin concentration in a tissue, cell, or a specified body part. Ballistic imaging consists of light photons that travel in a straight line through a scattering body tissue. These photons travel across short distances and are either absorbed or scattered. Optical imaging is used to detect breast cancer. The advantages of optical imaging include; portable and cheap, and it provides an excellent temporal response. However, optical imaging has poor contrast caused by increased scattering, the imaging depth is relatively low, and the images have low spatial resolutions.

Microwave imaging

This imaging tool examines the hidden structure in a body organ, cell, or tissue. This technique uses electromagnetic waves to show the shape and size of a given body part. Kwon and Lee (2016) describe microwave imaging as a technique that contrasts electric waves between tissues of a tumor and a normal breast within the microwave spectrum.³ Through the scattered and reflected signals within the breast, microwave imaging reconstructs the breast image to reveal its shape and size. Besides, microwave imaging uses laser infrared thermography with microwave energy for heating the breast tissues. This technique can trace the availability of cancer cells even at an early stage. Unfortunately, this imaging technique is limited by poor resolution, increased breast depth, poor microwave energy dissipation control, and low contrast images. However, microwave imaging has positive features, such as it is non-invasive and non-radioactive.

In conclusion, breast screening and diagnosis are vital for all women. With the emerging trends in breast imaging, health professionals should identify the most effective imaging technique with the least possibilities of side effects. Since the severity and incidences of breast cancer are rising rapidly, the government, through the health department, should provide periodic free screening services to minimize deaths related to breast cancer. With or without feeling a lump on the breast, women should take precautionary measures to prevent the spread of cancer cells in the breast, imaging being the most reliable technique.

References

1. Sree SV, Ng EY, Acharya RU, Faust O. Breast imaging: a survey. World journal of clinical oncology. 2011 Apr 10;2(4):171. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3100484/
2. Anandhamala GS. Recent trends in medical imaging modalities and challenges for diagnosing breast cancer. Biomedical and Pharmacology Journal. 2018 Sep 21;11(3):1649-58. Available at: https://biomedpharmajournal.org/vol11no3/recent-trends-in-medical-imaging-modalities-and-challenges-for-diagnosing-breast-cancer/
3. Kwon S, Lee S. Recent advances in microwave imaging for breast cancer detection. International journal of biomedical imaging. 2016 Oct;2016. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5210177/