When Are CT Scans, MRIs, and X-rays Used?

Dr. James - Orthopaedic Surgeon in Singapore

Medically reviewed by Dr. James Tan

While a physical examination can tell your doctor a great deal about your health, there are times when it is essential to take a closer look. Thanks to the incredible advancements in modern medical technology, doctors have the power to see far beneath the surface.

High-tech diagnostic imaging tests such as Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI), and X-rays have transformed medicine. These common examinations have greatly improved our ability to treat and prevent health conditions of all kinds. But, what exactly are CT scans, MRIs, and X-rays? How do medical professionals decide which is the best type of test, and what is it like to undergo one of these exams?

To help you understand what to expect at your next appointment and give you a better insight into the choices that your doctor is making for your health, let’s take a closer look at diagnostic imaging tests.

What Do X-rays, MRIs and CT Scans Do?

CT scans, MRIs, and X-rays are all imagining scans. They allow a medical professional to strategically zoom in on a particular part of your body and see what is going on inside. From broken bones to tumours to disease detection to diagnosing shoulder dislocation, these scans are utilised by healthcare professionals to look for potential conditions on a level that would have been unheard of not so many years ago. These are invaluable tools at every stage from detection to treatment to recovery.

All three of these imaging scans are used in the diagnosis process. Your healthcare professional will determine which option is best for you based on your symptoms and the results of a superficial exam. Their uses are rarely interchangeable so your doctor will choose the test that best suits the potential condition at hand.

When you arrive at your doctor’s office on the day of your test, you’ll find that the X-rays and CT scans are done in a few minutes. Meanwhile, MRIs can take anywhere from 15 minutes to a couple of hours, depending on the specific type of scan being done. All of these tests are painless, however, and an important part of your health journey.

What Is the Difference Between a CT Scan and an X-Ray?

As X-rays and CT scans are both quick processes, people often confuse these two types of tests. While they have a certain number of similarities, there are some key distinctions between the two tests. First and foremost, X-rays are used to check for fractures such as osteoporosis fractures and whiplash injury, disclosures, and breaks in bones as well as to check for conditions like pneumonia and some types of cancer. On the other hand, CT scans are a more sophisticated type of scan that is used to check for injuries to internal organs. While an X-ray can’t properly assess muscle or soft tissue damage, a CT scan can provide a closer look into elbow pains or knee pains and even possibly find the cause of regular muscle cramps.

The images that healthcare professionals see from an X-ray are two dimensions. Meanwhile, the results of a CT scan show a three-dimensional image of the scanned area. This 3D image provides a detailed image of the scanned area. By offering doctors a clearer image, the CT scan results make it possible to see potential injuries or sports injuries like running or squats, and diseases that would have otherwise been hidden. Of course, while this CT scan image provides a detailed look, that level of detail isn’t always required or helpful. This is why there are many cases where an X-ray is a more practical choice, like diagnosing hip and foot pains.

Talk to us today if you are looking to treat injuries from sports or overexertion.

What Is the Difference Between an MRI and a CT Scan?

In most cases, your doctor will opt for a CT scan before an MRI. A key reason for this is that a CT scan can take a quick series of pictures like an X-ray. They are quicker and more accessible for patients and healthcare facilities alike. CT scans are particularly helpful in cases where a person might not be able to lie still or hold their breath during an exam, which are two things that are required during an MRI.

CT scans are often the first choice scan for cancer detection as they can check for any spread in the disease and determine its stage. These scans are also useful in looking for internal bleeding or blood clots as well as injuries to your spine or brain injuries.

On the other hand, there are certain things that an MRI can detect that a CT scan can’t pick up. For example, certain cancers such as uterine cancer, prostate cancer, and types of liver cancer are nearly impossible to detect on CT scans. Cancer that may have spread to the bones or brain can also be checked by an MRI scan. Outside of cancer, MRIs are also the better choice for many types of soft tissue and joint issues like meniscus tears or rotator cuff injuries.

What Are the Differences Between an X-Ray and an MRI?

MRIs and X-rays provide your doctor with images of internal structures and tissues, and each one has its distinct advantages. X-rays are praised for being relatively low-cost and quick. They can provide a clear look at your bone structure to detect broken bones or tissue diseases. If you do sports like bouldering or pilates regularly and suspect a broken wrist, an X-ray will be the most definitive way to diagnose your injury.

An X-ray, however, can’t see great detail beyond this. It is also important to note that X-rays create ionising radiation. While this radiation is safe in small doses, it can be harmful during pregnancy or in cases where multiple scans are needed. Of course, your healthcare professional will review your medical history and decide on the effective option.

An MRI is a more extensive and time-consuming option, which means it may not be as readily available. While it doesn’t provide a detailed look at bony tissues, it does provide a clear look at injuries to ligaments in the knees, tendons, the spinal cord, and brain tumours as well as a wide range of other soft tissue injuries and diseases. MRI is frequently used to diagnose the issues and aftermath of knee injuries and shoulder injuries, which can usually happen from strenuous activities such as HIIT or F45 workouts. For chronic shoulder pain treatment, it is advisable to consult a doctor as soon as possible for pain management.

Since it works via magnetic resonance, it is safe to use regularly without the risk of radiation. There are a certain number of medical implants, however, that can be affected by magnetic fields so it’s not suitable for everyone. It is also worth noting that people with claustrophobia can have trouble with the nature of MRI exam spaces.

How to Request a CT Scan, MRI, or X-Ray in Singapore

Do you think that you might need a CT scan, MRI, or X-ray in Singapore? If you have any reason to believe that you need an exam, don’t delay! Timing is everything in successful detection and treatment. If you are confused, feel free to check out the differences between physiotherapy and orthopaedic surgery, or the differences between chiropractors, osteopaths, and physiotherapists to ensure you get the right help for your injuries.

Looking for orthopaedic treatment in Singapore or platelet-rich plasma treatment to speed up recovery? Talk to us today!

If you’d like to find us directly, visit one of our clinics below:

Camden Medical

1 Orchard Boulevard, #09-06

Singapore 248649

Mount Alvernia Hospital

820 Thomson Road

Medical Centre D #05-60

Singapore 574623

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About The Author

dr james tan

Dr James Tan Chung Hui

Dr James Tan is a skilled orthopaedic surgeon at Quantum Orthopaedics who has more than 10 years of experience in sports surgery and exercise medicine in Singapore. Apart from partnering with the industry to introduce various treatment techniques, Dr Tan has treated athletes from the Singapore National Teams and professional footballers from the Singapore Premier League and the Young Lions.

Dr Tan specialises in treating sports injuries of the knee, shoulder and elbow joints, as well as cartilage and meniscus surgery. He is a member of the elite Asian Shoulder and Elbow Group and a founding member of the Singapore Shoulder and Elbow Surgery Society.

Qualifications and Achievements
MBBS - National University of Singapore (NUS), Faculty of Medicine
Member of the Royal College of Surgeons of Edinburgh (MRCS)
MMed - Master of Medicine in Orthopaedic Surgery (NUS)
Fellow of Royal College of Surgeons (Edinburgh)
Adjunct Assistant Professor | NUS, LKC
Senior Consultant Orthopaedic Surgery, Sports and Exercise Medicine
Head of Department | Orthopaedic Surgery and Sports Medicine Centre
Principal Investigator of Tissue Engineering
National Medical Research Council grants
Collaboration with Scientists at NTU, TUM, A*Star, Osteopore & Trendlines Medical Singapore


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