Diagnostic Imaging

Diagnostic Imaging 

Diagnostic imaging is used across all fields of medicine to aid in the diagnostic process. Imaging technology is used in various ways to evaluate different components and structures of the body. Each type of imaging has strengths and weaknesses, which is why various imaging types exist.

 

MRI Scans

Magnetic Resonance Imaging (MRI) is a type of diagnostic imaging that takes pictures of organs and structures within the body.¹ MRIs use magnets, radio waves, and computers to create images of the organs and structures in the body, and can be completed with or without contrast.¹ Contrast is a solution injected through an IV before the image is taken. MRIs typically give better pictures of the brain, spinal cord, nerves, muscles, ligaments, and tendons.¹ An MRI can take anywhere from 30 to 50 minutes to complete.

There are two different types of MRIs: open-bore and closed-bore. Open-bore MRIs are machines that have an opening on one side. In these, the patient will lie on a table with one magnet above them and the other below them. These may be most effective for patients who suffer from claustrophobia.¹ Closed-bore MRIs are machines with a ring of magnets surrounding the patient. These leave little space between the machine and the patient, which can cause anxiety and discomfort to patients; however, closed-bore MRIs take better images inside the body than open-bore and are therefore preferred by most providers^.1

An MRI is typically performed with the intent of examining a specific set of structures or region of the body. For example, brain and spinal cord MRIs can help with the diagnosis of brain/spinal tumors, brain aneurysms, compression, inflammation, or pinched nerves in the spinal cord.¹ Cardio MRIs are used to look at all the heart chambers and diagnose tumors, infections, and inflammatory conditions.¹ Body MRIs can show tumors, vasculitis, inflammatory bowel diseases, and liver diseases.¹ Bone and joint MRIs are used to examine tumors or bone malformations and joint issues due to injuries.¹

 

MRA Scans

Magnetic Resonance Angiography (MRA) scans are a type of MRI that specifically looks at blood vessels.² These can be completed with or without contrast, although MRAs with contrast give a higher-definition image for the radiologist and provider to review. MRAs are sometimes used in place of an angiogram, without a catheter, making it more comfortable for the patient.²

MRA scans are typically done when the provider believes the patient has a narrowing or a blockage of blood vessels in their body. They can also look to see if the patient has an aneurysm, narrowing, bleeding, or dissection of the aorta for signs of heart disease, as well as to find the cause of a stroke.² MRA Scans last approximately 30-50 minutes.

 

CT Scans

Computerized Tomography (CT) scans are diagnostic images taken from multiple angles around the patient's body; when put together, the provider can examine all the body's bones, blood vessels, and soft tissue.³ These cross-sectional images give the provider a more detailed picture than regular X-rays. CTs are fast, only taking up to about 30 minutes, making them useful to check for internal injuries or conditions like appendicitis.³  CTs can be taken with or without contrast, and contrast can be given by mouth (PO) or injected via an IV.

As mentioned above, CTs are primarily ordered to diagnose bone tumors or fractures and find the exact location of tumors, infections, or blood clots.³ CTs also help monitor disease progression and/or treatments. They are also used to guide surgical procedures, help the provider acquire a biopsy, and aid in direct radiation therapy.³

A CT machine is commonly described as a doughnut standing on its side.³ In the middle cut-out is a table on which the patient will lie. If the patient needs a head CT, there may be a stand or brace that will keep the patient's head in place throughout imaging.³ The machine will move the table through the cutout while the CT tube moves around the patient.³ While it is moving, the tube will take dozens of photos, which will be interpreted by the radiologist and sent to the patient's provider.

 

LDCT

Low-Dose Computerized Tomography (LDCT) scans are a type of CT scan generally used as a preventive measure by a provider checking for lung cancer.⁴ LDCTs are recommended for individuals who smoke or have smoked and are 50+ years old.⁴ The technique for LDCTs is the same as that for CTs; the patient will lie on a flat table with a doughnut-shaped tube around them. While the table moves, the imaging equipment will take photos of the chest.⁴ LDCTs do not need to be done with contrast.

 

Ultrasounds

Ultrasound, commonly known as ultrasonography or sonography, is a type of diagnostic imaging that uses sound waves to make up pictures of organs and tissues in the body.⁵ There are a variety of ultrasounds, including Doppler, which is used on the outside of the body; vaginal, commonly known as a trans-vaginal ultrasound which can show views of the uterus and ovaries; rectal, commonly known as trans-rectal ultrasound, which is used to view the prostate gland; lastly, a trans-esophageal echocardiogram (TEE), which is used to see clear images of the heart. 

There are three main uses for ultrasound, the first being for pregnancy. Pregnancy ultrasounds are used to check the size, heart rate, and positioning of the fetus.⁵ They also look for birth defects as well as genetic disorders. During pregnancy ultrasounds, the ultrasound tech will also examine the position of the placenta and check the amount of amniotic fluid that surrounds the fetus.⁵

The second main use for ultrasound is diagnostic; this focuses on finding the cause of issues like pain and swelling, locating blockages, detecting and measuring growths (like cysts), and identifying structural problems in the patient's organs, glands, and blood vessels.⁵ 

The final main use is to guide biopsy procedures. Typically, an ultrasound-guided biopsy is ordered to help the provider see where tissue or fluid samples should be obtained with the biopsy needle.⁵ The length of the ultrasound will vary based on the need, though they typically take around 20-40 minutes. One common exception would be the examination of a fetus, which may take 1-2 hours. 

 

X-rays

X-rays are a type of diagnostic imaging that uses electromagnetic energy to create images of tissues, bones, and organs on film or a type of digital media.⁶ X-ray beams are a form of external radiation that goes through the body and creates a picture on an X-ray plate or digital media.⁶ This will create a black-and-white photo or ‘negative’ of the body structures.

X-rays use electromagnetic energy, so there should not be metals or jewelry on the body at the time of imaging. Parts of the body that are not being focused on for the X-ray will be shielded by a lead apron to limit radiation exposure.⁶ The patient must remain still while pictures are taken, or the image could be blurry. 

X-rays primarily examine the bones, teeth, chest, and abdomen. They are used to help diagnose fractures, infections, cancers of the bone and teeth, show arthritis in the joints of the bones, and help measure bone density.⁷ Chest X-rays may also aid in detecting lung infections like tuberculosis and pneumonia, and show if the patient's heart is enlarged, while abdominal X-rays can be used to find swallowed items.⁷ Depending on the patient's age, X-rays only take 5-15 minutes.  

 

Mammography

Mammography is a type of X-ray used for both screening and diagnostic procedures. Mammograms compress a patient’s breast(s) between two plates, then use X-rays to image the breast tissue.⁸ Mammograms are used for early breast cancer detection or to gather more information on lumps or indents of the breast. When radiologists review a mammogram, they look for high-density (white or gray) spots or areas, as normal tissue is not dense (see-through).⁸ 

 

Fluoroscopy

Fluoroscopy is another type of X-ray; Fluoroscopy is real-time video movement in the body using ionizing X-rays.⁹ The patient will lie on a procedure table and be placed in specific positions (and may need to be repositioned throughout the exam) depending on the areas of the body needing to be imaged. Fluroscopies are often used to see how well the stomach and intestines are functioning, to see if food is being swallowed correctly, and to help guide spine or joint injections.⁹ 

 

Colonoscopy

Colonoscopies are used for both screening and diagnostic procedures. Screening colonoscopies are used to check for colon and rectal cancers, as well as to check the colon after cancer treatment.¹⁰ Diagnostic colonoscopies look for problems like colon polyps, tumors, inflammation, diverticula, and ulcers. They can also be used to view narrowed areas of the colon.¹⁰ When the patient receives a colonoscopy, they will have to do a cleanse for 1-2 days prior. The procedure uses a flexible tube with a camera and light on one end, inserted in the rectum, then guided into the colon.¹⁰ This imaging procedure is often completed while the patient is under anesthesia and will give the provider a view of the colon and any possible problems. 

 

 

Bone Density Scans (DEXA)

Bone density scans, also known as DEXA scans, are tests used to help diagnose osteoporosis or osteopenia, help identify changes in bone density, and help detect areas at high risk for bone fractures.¹¹ DEXA scans utilize a machine that passes over the top of the patient’s body as they lie on a table and uses radiation to take a picture of the patient’s bones.¹¹ This test typically takes between 10-30 minutes.  

 

PET Scan

Positron Emission Tomography (PET) scans help diagnose conditions involving tumors, heart disease, brain disorders, and cancers.¹² For this scan, the patient will lie on an exam table that moves through the PET machine. Radioactive tracers are injected into the body and absorbed by diseased cells. The PET machine will create images based on the cells that absorb the tracers, which the physician can then study.¹²

 

As a Medical Assistant, it may be your job to give patients information on the procedures they are being referred to, obtain prior authorizations, and schedule the patient for said procedures. In many cases, you must also instruct the patient on preparing for their scheduled procedure. 

 

References

1. Cleveland Clinic (2022, May 9). MRI (Magnetic Resonance Imaging): What It Is, Types & Results. Retrieved January 24, 2024, from https://my.clevelandclinic.org/health/diagnostics/4876-magnetic-resonance-imaging-mri
2. The Johns Hopkins University (2019, November 19). Magnetic Resonance Angiography (MRA). Johns Hopkins Medicine. Retrieved January 24, 2024, from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/magnetic-resonance-angiography-mra
3. Mayo Foundation for Medical Education and Research (MFMER) (2022, January 6). CT Scan. Mayo Clinic. Retrieved January 24, 2024, from https://www.mayoclinic.org/tests-procedures/ct-scan/about/pac-20393675
4. Mayo Foundation for Medical Education and Research (MFMER) (2022, February 11). Lung Cancer Screening. Mayo Clinic. Retrieved January 24, 2024, from https://www.mayoclinic.org/tests-procedures/lung-cancer-screening/about/pac-20385024
5. National Library of Medicine (n.d.). Ultrasound. Medlineplus. Retrieved January 24, 2024, from https://medlineplus.gov/lab-tests/sonogram/
6. The Johns Hopkins University (2021, August 8). X-Rays. Johns Hopkins Medicine. Retrieved January 24, 2024, from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/xrays
7. Mayo Foundation for Medical Education and Research (MFMER) (2024, January 20). X-Ray. Mayo Clinic. Retrieved January 24, 2024, from https://www.mayoclinic.org/tests-procedures/x-ray/about/pac-20395303
8. National Institute of Biomedical Imaging and Bioengineering (n.d.). Mammography. Retrieved January 24, 2024, from https://www.nibib.nih.gov/science-education/science-topics/mammography
9. Centers for Disease Control and Prevention (2021, October 20). Fluoroscopy. CDC. Retrieved January 24, 2024, from https://www.cdc.gov/nceh/radiation/fluoroscopy.html
10. The Johns Hopkins University (2021, December 7). Colonoscopy. Johns Hopkins Medicine. Retrieved January 24, 2024, from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/colonoscopy
11. Mayo Foundation for Medical Education and Research (MFMER) (2022, September 21). Bone Density Test. Mayo Clinic. Retrieved January 24, 2024, from https://www.mayoclinic.org/tests-procedures/bone-density-test/about/pac-20385273
12. Cleveland Clinic (2022, October 19). PET Scan. Retrieved January 24, 2024, from https://my.clevelandclinic.org/health/diagnostics/10123-pet-scan