This world is revolutionizing with contemporary means, modern technologies and advance methods, numerous changes are seen in almost every aspect of life. But these revolutionary methods are useless without the health of individuals. There are many new diseases that have been discovered and they can not be detected without imaging modalities, certain diseases need screening at regular intervals during treatment and its all is possible due to medical imaging modalities. Medical imaging has changed the practice of medicine and medical imaging technology itself leading to enhancing the life saving capabilities and enlightening hope in individuals for winning the battle against so many destructive diseases. Medical imaging is an art, process and technique of designing visual representations of the interior body parts for diagnosis and treatment. In every field of medicine, effective decisions rely on correct diagnosis, it correctly asses, confirm, document course of disease and also the response of disease towards medication. So, here we have the list of Top 10 Most Used Medical Imaging Modalities that are widely used for diagnostic purpose.
10. Positron Emission Tomography (PET)
A Positron Emission Tomography scan uses radiation or nuclear medicine imaging, to create three dimensional, color images of the functional processes within the body.It is technology that is often used in combination with CT imaging, by using a scanner and a minor amount of radioactive glucose that is introduced in patient’s body by injecting through vein and computerized pictures of area inside the body where glucose is used. A PET CT scan comprises of two parts; a CT scan to recognize the location for the PET and then the PET scan itself. During some studies a contrast agent is used to see the image in more detailed. It can show how tissues and organs are working and the certain areas of corcern can be clearly seen.
It is a form of diagnostic technique that is used in nuclear medicine and in this technique radiopharmaceuticals are internally taken, and the emitted radiation is detected by external detectors that are known as gamma cameras and form two dimensional images of the body structures. It is different from diagnostic x ray as in diagnostic x ray the source of radiation is x ray tube whereas in this the source of radiations is patient itself.
8. DEXA Scan
Bone Mineral densitometry or DEXA scan is an imaging technique in which x rays are used to acquire the images that are particularly used to measure the density of bones. X –rays that pass through the bone create different densities on the film and these densities are therefore utilized to analyze the density of the bone.
Mammography is a specialized imaging modality that utilizes low energy X- rays to obtain very detailed images of breast tissue. The practice of mammography uses standardized views of the breasts for assessment and localization of various breast lesions. It is also an important screening tool for detecting early beast cancer in asymptomatic women. It also provides guidance for interventional investigation of breast lumps or lesions. Early detection of breast cancer helps the patient in early treatment and also increased rates of survival.
Diagnostic angiographic is a very useful medical imaging modality that is used for visualizing the lumen or inside of the blood vessels, especially the arteries, veins and the chambers of the heart by utilizing x-rays. In this study contrast media is injected into the blood vessels that underline the pathology. Angiography machines can either be conventional or digital subtraction angiography, the later one is the most commonly used. With the help of this modality obstructive vessels, bleeding vessels, aneurisms, arterio-venous malformations etc are diagnosed and the lives of numerous individuals can be saved through correct diagnosis.
It is an imaging modality in which x rays are used for real time visualization of body structures. During this technique, x rays are constantly emitted and detected on a screen, producing a dynamic image. The body structures transmit, deflect and absorb radiations differently and in this way different densities form a fluoroscopic image. The structure and function of the body parts can be easily studied with the help of dynamic images. High density contrast media is introduced that allow greater differentiation between structures. The real time two dimensional images that are created by Fluoroscopy can then be printed onto film if necessary. Some procedures that are performed by using Fluoroscopy include barium studies, micturating cysto urethrography, arthograms, HSG etc.
4. Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging is a medical imaging technique in which strong magnetic fields and radio waves are used to produce cross sectional images of internal body structures. The signal detected by an MRI machine depends on the water content and the magnetic properties of a defined area of the body and therefore varies in intensity and with the help of which different tissues can be distinguished from one another. It can give detailed information about structures within the body than can be obtained through plain radiography, ultrasound or CT scan. Detailed pictures of blood vessels, organs, joints, tendons, area of infections, tumors and many more are obtained from this modality. The use of contrast agent helps the medical specialists to visualize the MRI images more clearly. It also uses non ionization radiations and therefore contains no radiations hazards.
3. Computed Tomography (CT)
Computed Tomography also known as CAT scan, computed axial tomography is a medical imaging method in which x rays are used to create the three dimensional image of the body structures. The thin beam of x rays takes a number of cross sectional pictures of the area of interest from multiple angles. This data is then utilized to construct images and with the help of post processing multi planar imaging is possible. In some CT scan procedures, a contrast medium is injected to highlight organs or outline blood vessels so that the anomaly can be easily detected. CT scan is best to see bone, bleed and calcification and is very fast but it utilizes ionizing radiations and has radiation hazards.
Ultrasonography or diagnostic sonography is a diagnostic imaging technique in which high frequency sound waves are used for visualizing the internal structures of the body including tendons, vessels, joints, muscles and internal organs for possible lesion or pathology. In this the sound waves are sent into the tissue through ultrasound transducer, the returning sound wave is measured and the ultrasonography machine is capable of converting the sound echoes into a picture that is displayed on the screen. Doppler ultrasound is used to detect vascular problems by using the Doppler shift phenomenon. Ultrasound is easy to perform, cheap, movable and most importantly does no use ionizing radiations and therefore is completely safe and can be safely used for pregnant women. It is a critical device both for urgent and routine care diagnostics.
1. Plain Radiography
It is a medical imaging modality in which x rays are used to visualize the internal structures of the body. X-rays are a sort of electromagnetic radiation that emit from the x-ray tube and are passed through the body of the patient and are captured by the detector behind the patient. In X-ray technology the detector is a film sensitive to x rays. There is an alteration in the absorption of x rays by the different tissues of the body, soft tissues allow more radiation to pass and less to absorb, whereas dense bones allow more radiations to absorb and due to this variation a contrast is produced within the image and it give two dimensional representation of all the structures within the body of the patient.
Plain radiography is almost crucial in every medical setting and in all health care institutes. Majority of the patients with trauma and any confusing illness undergo plain radiography. It is the common test that is performed for diagnosis and it can examine cavities, broken bones and swallowed objects and many more.